3.3. What is process monitoring about?
Most industries have now realized that product quality is not an option. There was historical thinking that quality is the equivalent of "gold-plating" your product, but that has mostly fallen away. Product quality is not always a cost-benefit trade-off: it is beneficial to you in the long-term to improve your product quality, and for your customers as well.
As we spoke about in the univariate review section, good quality products (low variability) actually boost your profits by lowering costs in the long term. You have lower costs when you do not have to scrap off-specification product, or have to rework bad product. You have increased long-term sales with more loyal customers and improved brand reputation as a reliable and consistent supplier.
An example that most people in North America can relate to is the rise in Asian car manufacturers' market share, at the expense American manufacturers' market share. The market has the perception that Asian cars are more reliable than American cars and resale rates certainly reflect that. The perception has started to change since 2010, as North American manufacturers have become more quality conscious. That is an illustration of how lack of variability in your product can benefit you.
In order to achieve this high level of final product quality, our systems should be producing low variability product at every step of the manufacturing process. Rather than wait till the end of the process to discover poor quality product, we should be monitoring, in real-time, the purchased raw materials and also the intermediate steps in our process. When we discover unusual variability the lofty aim is to make (permanent) process adjustments to avoid that variability from ever occurring again.
Notice here that process monitoring is not intended to be automatic feedback control. It has the same principles of quantifying unusual operation (errors) and reacting to them in some way, but the intention with process monitoring is:
 - that any process adjustments are infrequent [not frequently on a set cycle, as feedback control does],
 - these adjustments are made manually [not automatically with actuators],
 - and take place due to special causes [not due to regularly occurring process disturbances].
As seen by the items in square brackets above, automatic feedback control is applied continuously by computer systems and makes short-term, temporary changes to the system to keep it at the desired target (called the setpoint) in the face of process disturbances. Process monitoring is very different therefore to feedback control.
Note that process monitoring is often called statistical process control (SPC). This can lead to unnecessary confusion with process control, i.e. the design and implementation of feedback control, feed-forward control and other automated control systems. We will not use the term SPC, rather we will use the term process monitoring.
3.3.1. Monitoring charts
We use monitoring charts, also called control charts, to display and detect this unusual variability. A monitoring chart is a display of one value (variable), against time, or in sequence order. These time-based plots also show some additional information: usually a target value, and one or more limits lines are superimposed on the plot. The plots are most useful when displayed in real-time, or close to real-time. There are various technical ways to express what a monitoring chart does exactly, but a general definition is that a monitoring chart helps you detect outliers and other unusual time-based behaviour.
The key points are that a monitoring chart:
 - is most often a time-series plot, or some sort of sequence plot,
 - a target value (center line) may be shown,
 - one or more limit lines are shown, such as the UCL (upper control limit) or LCL (lower control limit),
 - they are displayed and updated in real-time, or as close to real-time as possible, so that the chart appears to move from right to left.
Here is an example that shows these properties.
3.3.2. General approach
Monitoring charts are developed in 2 phases. You will see the terminology of:
 - Phase 1: building and testing the chart from historical data that you have collected. This phase is performed off-line, it is very iterative, and you will spend most of your time here. The primary purpose of this phase is to
 - find portions of the data that are from stable operation
 - use these stable portions to calculate suitable control chart limits
 - ensure that your chart works as expected based on historical data
 - Phase 2: We use the monitoring chart on new, fresh data from the process. This phase is implemented with computer hardware and software for real-time display of the charts. This phase is skipped if the phase 1 testing is not successful (e.g. too many false alarms). We discuss reasons for failure in the section on judging the chart's performance.
3.3.3. What should we monitor?
Any variable can be monitored. However, the purpose of process monitoring is so that you can react early to bad, or unusual operation. This implies we should monitor variables as soon as they become available, preferably in real-time. They are more suitable than variables that take a long time to acquire (e.g. laboratory measurements). We should not have to wait to the end of the production line to find our process was out of statistical control.
Data/measurements available at the start of your process, suc as raw material data from your supplier should also be monitored as soon as it is available, e.g. when received by your company, or even earlier - before the supplier ships it to you.
Intermediate variables measured from sensors at all points along the production process are (a) available much more frequently and without delay, (b) are more precise, (c) are usually more meaningful to the operating staff than final quality variables from the lab, and (d) contain the "fingerprint" of the fault, helping the engineers with diagnosis of what the problem is and point to which part(s) of the process need adjustment (see MacGregor, 1997).
Note that we do not have to monitor variables that are measured only from on-line sensors. The variable could be a calculation made from the on-line measurements.
For example, an energy balance could be calculated from various thermocouples on the process and the degree of mismatch in the energy balance could be critical to quality. For example, the mismatch could indicate an unexpected source of heat into or out of the process - so monitor that mismatch, rather than the raw temperature data. Similarly, a mass balance can be monitored in real-time, such as a total mass balance, or a carbon (or other elemental) balance. This is common in the mining industry and bio-processing industries.
Discuss one of these unit operations with your colleague. Which variables would you monitor?
 - Waste water treatment process
 - Tablet/pharmaceutical manufacturing
 - Oil and gas (e.g. a distillation column)
 - Food-processing or bio-engineering (e.g. fermentation) unit
 - Mineral processing plant (e.g. a flotation cell)
 - Plastics processing (e.g. a twin-screw extruder)
3.3.4. In-control vs out-of-control
Every book on quality control gives a slightly different viewpoint, or uses different terminology for these terms.
In this book we will take "in-control" to mean that the behaviour of the process is stable over time. Note though, that in-control does not mean the variable of interest meets the specifications required by the customer, or set by the plant personnel. All that "in control" means is that there are no special causes in the data, i.e. the process is stable. A special cause, or an assignable cause is an event that occurs to move the process, or destabilize it. Process monitoring charts aim to detect such events. The opposite of "special cause" operation is common cause operation, or stable process operation.
Our objective: quickly detect abnormal variation, and fix it by finding the root cause. In this section we look at the "detection" problem. Diagnosis and process adjustment are two separate steps that follow detection.


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Born: 1913, Independence, Wisconsin
Describes reconstruction of the courtroom in Nuremberg [Interview: 1990]
An architect whose name I forget now, who worked for OSS, was pushed in very early and he immediately came up with the design and it required knocking out some walls and to make the courtroom larger so there'd be room for the press and for visitors. And he did a terrific job on this, and also made cubicles for the photographic apparatus that would be used and for the sound equipment. Every bit of the trial was recorded on tape, so that there could never be any argument about what was said.
Drexel Sprecher was educated at the University of Wisconsin, the London School of Economics, and at the Harvard School of Law before receiving a position at the U.S. Government's Labor Board in 1938. He enlisted in the American military after the United States declared war on Germany, and was posted to London. After the war, Sprecher served as a prosecutor of Nazi war criminals at the Nuremberg trials.
US Holocaust Memorial Museum

source: HuggingFaceFW/fineweb-edu


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Australian researchers have revealed a new pattern of ocean circulation which will change our understanding of marine events.
Research at the University of Melbourne and the Bureau of Meteorology has overturned conventional ideas of ocean circulation.
Rather than moving simply in large clockwise (northern hemisphere) and anti-clockwise (southern hemisphere) gyres, the open waters of the southeast Indian Ocean are flowing east-west in bands, Prasanth Divakaran, a PhD candidate in the University's School of Earth Sciences, and his colleagues have shown.
The findings have important implications for our understanding of all sorts of ocean events from the movements of fish and marine life to the prediction of weather and climate.
"For instance," he says, "We found that ocean eddies—the marine analogues of atmospheric weather systems like tropical cyclones—form off Australia and begin a three-year journey across the Indian Ocean along what we call 'ocean arteries', transporting sea-water and biology with them."
Prasanth's work is being released for the first time in public through Fresh Science, a communication boot camp for early career scientists held at the Melbourne Museum. He was one of 16 winners from across Australia.
Prasanth is also presenting his research at the XXV International Union of Geophysics and Geodesy General Assembly in Melbourne this week.
On the basis of initial studies of water movement, Prasanth analysed a model of the circulation of the southeast Indian Ocean using advanced computing and new software for visualising the results. He and his colleagues then checked their findings against satellite observations.
"New international satellites and modern technologies developed in Australia helped to reveal the previously unknown ocean circulation patterns."
The results are also in keeping with some of the latest research from overseas, he says.
The basin-wide ocean currents the researchers revealed are organised into alternating bands, which connect the north-south currents on the east and west side of the Ocean.
"They look a bit like the patterns seen on the surface of Jupiter."
Recent work on the lobster life cycle around Western Australia has shown that the probability of growing into an adult depends on which deep artery of ocean circulation the larvae are swept into.
"Nature has known about these ocean arteries for centuries, but we humans have only just discovered them."
Understanding the impact of the arteries on ocean heat transport and climate is critical, Prasanth says.
- For interviews, contact Prasanth Divakaran on 0421 936 761 or _EMAIL_
- For Fresh Science, contact AJ Epstein on 0433 339 141 or _EMAIL_, Sarah Brooker on 0413 332 489 or Niall Byrne on _EMAIL_

source: openbmb/Ultra-FineWeb


text: I have these questions and I'm not sure which formula to use in each: This one is confusing as the distances are in miles rather than kilometers: 1. A car is travelling north along a highway and the driver notices that, although the speedometer reads 60mph he actually covers a distance of 5 miles in 5.5 minutes. Calculate the speed of the car. 2. A child can produce a power of 200W. He has to shovel 1000kg of sand from his drive on to the back of a lorry which is at a height of 0.9m above the ground. What is the smallest energy required to shovel the sand? 3. Calculate the shortest possible time that he would need to shovel the sand on to the lorry.


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5 Amazing Fish Spawning Facts You May Not Know
Fish behavior, specifically fish spawning behavior, can be absolutely amazing. There's always something new you can learn about fish species behavior when you're out on the water or reading about your favorite sport fish. Of course, this also includes learning about the incredibly unique life cycle that each fish species progresses through during its existence.
Throughout the course of my online and offline fishing education, I've discovered some pretty amazing facts about fish spawning.
- Snook are an amazing saltwater fish because the males actually reverse sex and change into females after the spawning season, which is generally during the fall. According to FWC biologists, the switch takes place when the species are between one and seven years old.
- Pacific salmon (including chinook, chum, coho, pink, and sockeye species) swim hundreds of miles from the ocean back to the freshwater streams where they were hatched in order to spawn.
- Since fish spawning activity is influenced by water temperature changes, the Tennessee Wildlife Resources Agency publishes an online chart that outlines the temperature ranges at which specific freshwater species spawn in the state of Tennessee.
- Based on information provided by the Indiana Division of Fish & Wildlife, freshwater drum make a croaking or "drumming" sound using muscles in their swim bladder during spawning.
- Schools of bonefish have been found to swirl like an underwater tornado in offshore waters when in spawning mode. Since bonefish primarily live on the saltwater flats of the Florida Keys and the Bahamas, it's rare to see a school of bonefish exhibiting these behaviors in offshore waters.
The most important thing to remember about fish spawning is that the process is essential for maintaining healthy fish populations. Always check your state fishing regulations and release fish that appear to be preparing to spawn.
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The Birth of the Virtual Machine, a Quest for Hybrid CAD29 May, 2008
Archimedes Project and Synchronous Technology take center stage at Siemens event.
Archimedes, a classical mathematician who died 2,200 years ago, is about to become part of the PLM (product lifecycle management) lexicon.
Soon after the ink dried on its acquisition of UGS, Siemens' Automation & Drives (A&D) division began working on a project dubbed Archimedes. Discussing it in the company's internal publication titled Pictures of the Future, publisher Arthur F. Pease wrote, "Siemens' recent acquisition of UGS has given its [A&D] Group... the tools to merge the real and virtual worlds of production" ("Factories of the Future — UGS and Siemens," Fall 2007). For more on the Archimedes Project, read "Event Report: UGS Media/Analyst Conference."
At Siemens' 2008 media and analyst briefing, which took place in Boston, Massachusetts, in May, Michael Weyrich, leader of new-generation business at Siemens A&D, introduced tangible evidence of Archimedes in operation. By marrying UGS's NX to Siemens' motion-control capabilities, Siemens has developed the Virtual Machine, which connects CAM (computer-aided manufacturing) to CNC (computer numerical control).
CNC Behavioral Science
Generally, a CAM program simulates the machining operations by animating the machine's movements based on kinematics, the mechanical motions predicted based on physics. However, in the physical world, the CNC operator uses a controller attached to the machine to perform the required tasks.
"In the Virtual Machine, NX takes into account the unique machine-tool characteristics of the real machine's controller," Weyrich said, "so information like how a machine is configured on a certain shop floor, for example, will be part of the simulation."
With Siemens' Virtual Machine, the simulation process is driven not only by kinematics but also by the motion algorithms used by an actual 840D controller. Therefore, it is expected to faithfully depict the cutting conditions, axis movements, collisions, work piece geometry, and motion behaviors of the machine tools equipped with a Siemens 840D control.
The virtual machine can physically be found at INDEX, a CNC machine supplier headquartered in Esslingen, Germany. It is now part of what the company delivers to its customers along with the physical hardware.
The Virtual Machine, a use-case scenario derived from Siemens' Archimedes Project, produces accurate simulation of machining operations by incorporating the controller's algorithm.
Wolfgang Schloegl, Siemens' digital factory team leader, followed Weyrich's virtual machine presentation with another that focused on the virtual factory, or E4DF (engineering for digital factory). In his view, the major shortcomings in today's engineering are:
- unsynchronized processes
- redundant data entry, processing, and storage
- insufficient validation of engineering results
His recommendation? Use Siemens' SIMATIC Automation Designer software along with Teamcenter as the data backbone. In its online literature promoting SIMATIC's openness as an advantage, Siemens states, "The previously separate worlds of mechanical components, electrical systems, and automation are now represented transparently in one plant structure. This guarantees data consistency. The result is that existing software tools can easily be used again and combined with SIMATIC Automation Designer."
With SIMATIC, CAD diagrams form the basis for plant layout. Once read into SIMATIC, they become the touchstones for configuring the production process. "The product has been field-tested for 1.5 years," said Schloegl. "It's now ready in a way that we can sell it."
By the end of this month, SIMATIC 3.0 should be available, along with E-CAD Extension Packages for automatically generating and integrating circuitry design. Schloegl revealed that SIMATIC will begin using JT, a lightweight file format developed by UGS, for visualization of factory components in 2009.
Live Rules Overrule Feature History
Synchronous Technology, Siemens' answer for combining freeform and parametric modeling, had been in incubation in a development lab at UGS before the acquisition. "When Siemens found out we had been working on this, they were delighted," said Chuck Grindstaff, Siemens' executive vice-president of products. With Siemens' contribution to the R&D budget, Synchronous Technology swiftly made its debut last month (for more information, read "Siemens Breaks Free from History."
In the first quarter of 2008, three history-based CAD vendors — Dassault, PTC, and Siemens — unveiled their own solutions that allow CAD users to employ a mix of modeling approaches. In February, PTC introduced a new version of Pro/ENGINEER that incorporates certain freeform-modeling features from CoCreate (acquired by PTC in October 2007). In April, Dassault previewed CATIA Live Shape, a freeform-modeling module for CATIA users.
Evan Yares, a CAD industry veteran in attendance at the Siemens event, said that what CAD vendors are pitching as freeform modeling may be described more accurately as "feature-imprint modeling."
Unlike the freeform-modeling methods found in software programs widely used by animation artists and game developers (such as Autodesk 3d Studio Max or Maya), the method now making its way into CAD packages relies on the recognizable topology of mechanical features (holes, tubes, and shafts) and makes every effort to retain the surface and geometric relationships. Therefore, Yares argued, the deformation is based on the existing imprint of a feature.
Synchronous Technology relies on Live Rules, a set of algorithms for detecting and recognizing standard mechanical features, to let the software intelligently reshape the affected geometry in response to a user's pushes, pulls, and dimension-driven changes. Live Rules can be disabled when a user wants to make an unorthodox change that might break the generally accepted associativities and constraints in a feature. Conversely, users also have the option to place locked constraints (or parameters) on a model.
In the demonstration, Dan Staples, director of Solid Edge product development, demonstrated how one can use Synchronous Technology to edit a Solid Edge assembly containing a SolidWorks part and an Inventor part. The new releases of NX and Solid Edge (dubbed Solid Edge with Synchronous Technology, or SEST for short) both feature Synchronous Technology.
Siemens promotes upcoming releases of NX and Solid Edge with Synchronous Technology as CAD tools with the potential to offer dramatically higher productivity in multi-CAD environments.
NX 6 features Product Template Studio, a way to publish a simplified parametric model from a complex part as input. The tool is designed to let users automatically generate a brand new part based on an existing one through guided input fields, bypassing the need to directly interact with the geometry.
With NX 6, using the mix-mesh approach, a user can prepare a mesh model for analysis with different mesh densities for different regions. The tool is particularly useful when dealing with products with a mix of simple and complex curvatures or a combination of thick and thin surfaces.
Throughout the last several years, digital prototyping has become the new mantra for CAD and PLM vendors. It's an ambitious vision, wherein everything taking place on the factory floor — from the tilt of an automatic drilling arm to the posture of an assembly worker — is simulated with digital replicas first. Siemens' progress report on the Archimedes Project proves that having a hardware giant for a parent company can be an advantage.
Autodesk Technical Evangelist Lynn Allen guides you through a different AutoCAD feature in every edition of her popular "Circles and Lines" tutorial series. For even more AutoCAD how-to, check out Lynn's quick tips in the Cadalyst Video Gallery. Subscribe to Cadalyst's Tips & Tricks Tuesdays free e-newsletter and we'll notify you every time a new video tip is available. All exclusively from Cadalyst!


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|Image from The Life of King Edward the Confessor: Exract from Folio 9r:Edward is received in England, and is crowned.|
Images of several of our important collections available online:
- Newton papers
A collection documents Sir Isaac Newton's writings and ideas consisting primarily of letters to and from 17th and 18th century scientists, including Oughtred, Cavendish, Briggs, Fermat, Oldenburg, Halley, Boyle, and others.
- Gutenberg Bible.
The first substantial work printed in Europe from moveable metal type, the so-called Gutenberg or 42-line Bible, produced in Mainz around 1455 by Johann Gutenberg, Johann Fust and Peter Schoeffer.
- Conrad Martens Sketchbooks I and III
Two of the sketchbooks of the artist who accompanied Darwin on the voyage of the Beagle.
- Book of Deer
Images from the illuminated tenth-century Gospel book (MS. Ii.6.32).
- Genizah Collection
Digitized images of some of the Taylor-Schechter Genizah Fragments held by Cambridge University Library.
- MS. Ee.3.59: The Life of King Edward the Confessor
The only copy of an illustrated Anglo-Norman verse Life of St Edward the Confessor, written in England probably in the later 1230s or early 1240s, and preserved in this manuscript, executed c. 1250-60.
- Royal Commonwealth Society Photograph Project
The RCS photograph gallery seeks to demonstrate the variety of photographs contained in the RCS Collection. It contains over 700 digitised images, dating from the late 19th century to the mid-1980s.


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Historical maps are an important tool for analyzing changes in urban development. But these maps only provide 2D information, and oftentimes not much is known about building height.
With this in mind, a research team from Skoltech (Russia) and FBK (Italy) developed a machine learning algorithm that can assess building height from historical maps, which could help researchers better understand the forces that shaped cities to what we see today.
Nowadays, we've become pretty used to having 3D maps at our disposal, but this is a luxury we take for granted too easily. For the vast majority of our history, maps and urban imagery were restricted to 2D information.
A team of researchers led by Elisa Mariarosaria Farella from the Fondazione Bruno Kessler (FBK) in Trento, Italy, wanted to see how the height of buildings in historical maps can be inferred. They developed a machine learning algorithm that was first trained on sample data, and then asked it to predict buildings' heights.
The algorithm's assessment is based on several "predictors" — variables that are assumed to have some connection (not necessarily a direct or causal connection) to the objective (in this case, the building height). Researchers used things like a building area, its type (whether it was residential, historical, etc), its distance to other buildings, and so on.
They then ground-truthed the model predictions and finessed it with historical photos (where available) and improved mathematical algorithms, using four historical maps of Trento (years 1851, 1887, 1908, and 1936) and Bologna (years 1884 and 1945),
Overall, the results were good, researchers write in the study.
"The reliability of the proposed approach was verified, testing the method on different datasets and epochs. The achieved results proved to be consistent with our accuracy targets and the complexity of such historical urban contexts. The implemented method is flexible and extendable, relying mainly on geometric and neighbour characteristics derivable from the datasets and adaptable categorical data."
They are now looking at ways to improve the process even further and generalize the method, which could make it much easier to digitize historical maps from all around the world and enhance them to 3D.
"The implemented learning and predictive procedure tested on historical data has proved to be effective and promising for many other applications. Based on few attributes for the prediction, it will soon be expanded to diverse real-life contexts with missing elevation data. The resulting models will be a great help in bridging the geospatial knowledge gap in past or remote situations" Emre Ozdemir, a Skoltech and FBK Trento PhD student, explains.
The study was published in MDPI Applied Sciences.


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- Heavy ions and X-rays in brain tumor treatment : a comparison of their biological effects on tissue slice cultures (2009)
- Background: In this interdisciplinary project, the biological effects of heavy ions are compared to those of X-rays using tissue slice culture preparations from rodents and humans. Advantages of this biological model are the conservation of an organotypic environment and the independency from genetic immortalization strategies used to generate cell lines. Its open access allows easy treatment and observation via live-imaging microscopy. Materials and methods: Rat brains and human brain tumor tissue are cut into 300 micro m thick tissue slices. These slices are cultivated using a membrane-based culture system and kept in an incubator at 37°C until treatment. The slices are treated with X-rays at the radiation facility of the University Hospital in Frankfurt at doses of up to 40 Gy. The heavy ion irradiations were performed at the UNILAC facility at GSI with different ions of 11.4 A MeV and fluences ranging from 0.5–10 x 106 particles/cm². Using 3D-confocal microscopy, cell-death and immune cell activation of the irradiated slices are analyzed. Planning of the irradiation experiments is done with simulation programs developed at GSI and FIAS. Results: After receiving a single application of either X-rays or heavy ions, slices were kept in culture for up to 9d post irradiation. DNA damage was visualized using gamma H2AXstaining. Here, a dose-dependent increase and time-dependent decrease could clearly be observed for the X-ray irradiation. Slices irradiated with heavy ions showed less gamma H2AX-positive cells distributed evenly throughout the slice, even though particles were calculated to penetrate only 90–100 micro m into the slice. Conclusions: Single irradiations of brain tissue, even at high doses of 40 Gy, will result neither in tissue damage visible on a macroscopic level nor necrosis. This is in line with the view that the brain is highly radio-resistant. However, DNA damage can be detected very well in tissue slices using gamma H2AX-immuno staining. Thus, slice cultures are an excellent tool to study radiation-induced damage and repair mechanisms in living tissues.


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Acidic weathering of basalt and basaltic glass: 1. Near-infrared spectra, thermal infrared spectra, and implications for Mars
MetadataShow full item record
Horgan, Briony H. N.
Smith, Rebecca J.
Cloutis, Edward A.
Christensen, Philip R.
Horgan, B.N.H., R.J. Smith, E.A. Cloutis, P. Mann, and P.R. Christensen (2017) Acid weathering of basalt and basaltic glass: 1. Near-infrared spectra, thermal infrared spectra, and implications for Mars. Journal of Geophysical Research: Planets, 122, 172-202. DOI:10.1002/2016JE005111.
Acid-leached rinds and coatings occur in volcanic environments on Earth and have been identified using orbital spectroscopy on Mars, but their development is poorly understood. We simulated long-term open-system acidic weathering in a laboratory by repeatedly rinsing and submerging crystalline and glassy basalts in pH ~ 1 and pH ~ 3 acidic solutions for 213 days and compared their visible/near-infrared (0.3–2.5 μm) and thermal infrared (5–50 μm) spectral characteristics to their microscopic physical and chemical properties from scanning electron microscopy (SEM). We find that while alteration at moderately low pH (~3) can produce mineral precipitates from solution, it has very little spectral or physical effect on the underlying parent material. In contrast, alteration at very low pH (~1) results in clear silica spectral signatures for all crystalline samples while glasses exhibit strong blue concave-up near-infrared slopes. SEM indicates that these spectral differences correspond to different modes of alteration. In glass, alteration occurs only at the surface and produces a silica-enriched leached rind, while in more crystalline samples, alteration penetrates the interior to cause dissolution and replacement by silica. We confirm that glass is more stable than crystalline basalt under long-term acidic leaching, suggesting that glass could be enriched and common in terrains on Mars that have been exposed to acidic weathering. Leached glasses are consistent with both OMEGA and Thermal Emission Spectrometer (TES) spectra of the Martian northern lowlands and may contribute to the high-silica phases detected globally in TES Surface Type 2. Thus, both glass-rich deposits and acidic weathering may have been widespread on Mars.


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In the Field
West African Human Rights Training Initiative
Conflict and Instability in West Africa
For the last 20 years, the Mano River sub-region of West Africa (Guinea, Sierra Leone, Liberia, Côte d'Ivoire) has been ravaged by a region-wide conflict, with guns, youth combatants and refugees spilling over porous borders. In 2011, a renewed political crisis in Côte d'Ivoire once again threatens to pull the entire sub-region back into armed conflict and chaos.
With conflicts marked by "blood diamonds," child soldiers and widespread sexual violence, the human rights fallout for many West Africans has been, and continues to be, devastating. But human rights abuses have not just been a consequence of war and conflict. Impunity for human rights violations has itself been a chronic source of instability and an obstacle to long-term peace.
Ultimately, building positive peace in the sub-region means building better and more accountable governments, but this cannot be done without a vibrant and vigorous civil society with the tools and training to press government for necessary redress and reform.
Strengthening Human Rights Organizations
The West African Human Rights Training Initiative (WAHRTI) is a regional partnership between the Joan B. Kroc Institute for Peace & Justice (IPJ), the Open Society Initiative for West Africa and the leading human rights organizations in the Mano River region.
The primary goal of the initiative is to strengthen the ability of select human rights organizations to pressure their governments for reform and accountability for human rights abuses by engaging in a three-step process of human rights investigation, report writing and advocacy.
The IPJ believes that continuing advocacy efforts by local human rights defenders will be central to promoting the consolidation of a just and lasting peace in the Mano River region.
To date, the IPJ has conducted intensive on-the-ground trainings with human rights organizations in Guinea, Liberia and Sierra Leone. The trainings cover research design, investigative and field research skills and analysis, report writing and research-based advocacy.
While the classroom workshops provide an important foundation, the sustained and applied nature of the WAHRTI training cycle is key to the program's success. As of mid-2012, nine local partners are now working to document pressing human rights issues with IPJ mentorship and OSIWA's financial support:
- Avocats Sans Frontières (ASF, Guinea), Prolonged pre-trial detention in Guinea's prisons and police stations.
- Les Mêmes Droits Pour Tous (MDT, Guinea), Police torture.
- Agenda for Development Alternatives (AGENDA, Liberia), Discrimination against persons with disabilities.
- Center for Transparency and Accountability in Liberia (CENTAL, Liberia), Corruption in the education sector and its effect on the right to education.
- Center for Accountability and the Rule of Law (CARL, Sierra Leone): Prolonged pretrial detention in Freetown's central prison.
- Lawyers Center for Legal Assistance (LAWCLA, Sierra Leone), Abuses against commercial sex workers by the police.
- Ivoirian League for Human Rights (LIDHO), Violations of freedom of speech and assembly.
- Action for the Protection of Human Rights (APDH), Violations of physical integrity in south-west Côte d'Ivoire.
- The Association of Women Jurists of Côte d'Ivoire (AFJCI), Female genital mutilation as a human rights violation.
Following a January 2012 training workshop, the IPJ is working with three project partners in Côte d'Ivoire to develop research plans for 2012 (APDH, LIDHO and AFJCI).
For more information about the IPJ's work in West Africa, please contact Assistant Professor Dustin Sharp.
To learn more, read an interview with Professor Sharp regarding the project.


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Training Course on Science Classroom Supervision is one of the SEAQIS' flagship programmes to equip school principals and supervisors in academic supervision. SCS activity was held from 24 October to 2 November 2022 through online platform with 16 principals, vice principals, and supervisors who had passed the selection. Dr Indrawati as the Director of SEAQIS officially opened the SCS 2022, while Mr Reza Setiawan (Deputy Director for Programme) officially closed this event.
In the beginning and at the end of the activity, the participants were required to do a pre-test as well as a post-test. The event was facilitated by the experts in the field of education and supervision, such as Dr Harry Firman (Universitas Pendidikan Indonesia); Prof Dr H. Jam'an Satori (Universitas Pendidikan Indonesia); Prof Dr H. Johar Permana (Universitas Pendidikan Indonesia); and SEAQIS academic team with synchronous and asynchronous learning models. Through academic supervision activity, principals or supervisors are expected to provide services, guidance, and assistance to improve the competence of teachers in learning and classroom management.
In this SCS activity, the participants had a lot of discussion with the resource persons and facilitators regarding the materials on Trends and Issues on Science Education, Science Classroom Supervision New Paradigm, Professional Learning Community (PLC), and so on. They also responded to each other while presenting the results of their tasks. During the closing, Ms Andri Novi Lestari gave her testimony after following all the SCS activities and expressed her gratitude to SEAQIS for organising this insightful activity.


How does the Bird Flu Spread?
Bird flu is spread through the feces and secretions of infected birds. Once the virus has been shed by the carrier bird, it will remain in the air for a few hours until a person comes into contact with it. Also, touching infected birds or coming into contact with surfaces or dirt that contain the virus can help spread the disease.


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Lennox & Addington is an excellent destination for bird watching. More than 350 species can be found within our borders. One hotspot in particular for birding enthusiasts is Amherst Island. It's a wonderful place to view and learn about a variety of owls. The most common species found here during the winter are the Northern Saw-whet Owl, Long-eared Owls, with smaller numbers of Barred Owls, Great Horned Owls, and a few Boreal Owls and Great Grey Owls. Snowy Owls, as well as the Northern Hawk Owls, are usually found in trees and on fence posts or hydro poles near open fields throughout the Island.
While bird watching, please respect the wildlife and vegetation on your visit. Remember not to get too close and move and speak quietly. Avoid the use of a flash if you are taking photographs.
Check out these websites for more information.
Kingston Field Naturalists


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Altair 8800 Computer with 8 inch floppy disk systemThe MITS Altair 8800 was a microcomputer design from 1975, based on the Intel 8080 CPU and sold as a mail-order kit through advertisements in Popular Electronics, Radio-Electronics and other hobbyist magazines. The designers intended to sell only a few hundred to hobbyists, and were surprised when they sold thousands in the first month. Today the Altair is widely recognized as the spark that led to the personal computer revolution of the next few years: The computer bus designed for the Altair was to become a de facto standard in form of the S-100 bus, and the first programming language for the machine was Microsoft's founding product, Altair BASIC. History
While serving at the Air Force Weapons Laboratory at Kirtland Air Force Base, Ed Roberts and Forrest M. Mims III decided to use their electronics background to produce small kits for model rocket hobbyists. In 1969, Roberts and Mims, along with Stan Cagle and Robert Zaller, founded Micro Instrumentation and Telemetry Systems (MITS) in Roberts' garage in Albuquerque, New Mexico, and started selling radio transmitters and instruments for model rockets.The model rocket kits were a modest success and MITS wanted to try a kit that would appeal to more hobbyists. The November 1970 issue of Popular Electronics featured the Opticom, a kit from MITS that would send voice over a LED light beam. Mims and Cagle were losing interest in the kit business so Roberts bought his partners out, then began developing a calculator kit. Electronic Arrays had just announced a set of 6 LSI ICs that would make a four function calculator. The MITS 816 calculator kit used the chip set and was featured on the November 1971 cover of Popular Electronics. This calculator kit sold for $175 ($275 assembled.) Forrest Mims wrote the assembly manual for this kit and many others over the next several years. He often accepted a copy of the kit as payment.The calculator was successful and was proceeded by several improved models. The MITS 1440 calculator was featured in the July 1973 issues of Radio-Electronics. It had a 14 digit display, memory and square root. The kit sold for $200 and the assembled version was $250. MITS later developed a programmer unit that would connect to the 816 or 1440 calculator and allow programs of 256 steps.In additions to calculators, MITS made a line of test equipment kits. These included an IC tester, a waveform generator, a digital voltmeter and several other instruments. To keep up with the demand, MITS moved into a larger building at 6328 Linn NE in Albuquerque in 1973. They installed a wave soldering machine and an assembly line at the new location. In 1972, Texas Instruments developed its own calculator chip and started selling complete calculators at less than half the price of other commercial models. MITS and many other companies were devastated by this, and Roberts struggled to reduce his quarter-million-dollar debt. Popular Electronics
January 1975 Popular Electronics with the Altair 8800 computerIn January 1972, Popular Electronics merged with another Ziff-Davis magazine, Electronics World. The change in editorial staff upset many of their authors and they started writing for a competing magazine, Radio-Electronics. In 1972 and 1973 some of the best construction projects appeared in Radio-Electronics. Art Salsberg became editor in 1974 with goal of reclaiming the lead in projects. He was impressed with Don Lancaster's TV Typewriter (Radio Electronics, September 1973) article and wanted computer projects for Popular Electronics. Don Lancaster did an ASCII keyboard for Popular Electronics in April 1974. They were evaluating a computer trainer project by Jerry Ogdin when the Mark-8 8008 based computer by Jonathan Titus appeared on the July 1974 cover of Radio-Electronics. The computer trainer was put on hold and the editors looked for a real computer system. (Popular Electronics gave Jerry Ogdin a column, Computer Bits, starting in June 1975.) One of the editors, Les Solomon, knew MITS was working on an Intel 8080 based computer project and thought Roberts could provide the project for the always popular January issue. The TV Typewriter and the Mark-8 computer projects were just a detailed set of plans and a set of bare printed circuit boards. The hobbyist faced the daunting task of acquiring all of the integrated circuits and other components. The editors of Popular Electronics wanted a complete kit in a professional looking enclosure.The typical MITS product had a generic name like "Model 1600 Digital Voltmeter." Ed Roberts was busy finishing the design and left the naming of the computer to the editors of Popular Electronics. At the first Altair Computer Convention (March 1976) editor Les Solomon told the audience that the name was inspired by his 12-year-old daughter, Lauren. "She said why do not you call it Altair - that's where the Enterprise is going tonight." The Star Trek episode is probably Amok Time, as this is the only one from The Original Series which takes the Enterprise crew to Altair (Six).A more probable version is that the Altair was originally going to be named the PE-8 (Popular Electronics 8-bit), but Les Solomon thought this name to be rather dull, so Les, Alexander Burawa (associate editor), and John McVeigh (technical editor) decided that "It's a stellar event, so let's name it after a star." McVeigh suggested "Altair", the twelfth brightest star in the sky.Ed Roberts and Bill Yates finished the first prototype in October 1974 and shipped it to Popular Electronics in New York via the Railway Express Agency. However, it never arrived due to a strike by the shipping company. The first example of this groundbreaking machine isthereforelost to history. Solomon already had a number of pictures of the machine and the article was based on them. Roberts got to work on building a replacement. The computer on the magazine cover is an empty box with just switches and LEDs on the front panel. The finished Altair computer had a completely different circuit board layout than the prototype shown in the magazine. The January 1975 issues appeared on newsstands a week before Christmas of 1974 and the kit was officially (if not yet practically) available for sale. Intel 8080
Ed Roberts had designed and manufactured programmable calculators and was familiar with the microprocessors available in 1974. The Intel 4004 and Intel 8008 were not powerful enough, the National Semiconductor IMP-8 and IMP-16 required external hardware, the Motorola 6800 was still in development so he chose the 8-bit Intel 8080. At that time, Intel's main business was selling memory chips by the thousands to computer companies. They had no experience in selling small quantities of microprocessors. When the 8080 was introduced in April 1974, Intel set the single unit price at $360. "That figure had a nice ring to it," recalled Intel's Dave House in 1984. "Besides, it was a computer, and they typically cost thousands of dollars, so we felt it was a reasonable price." Ed Roberts had experience in buying OEM quantities of calculator chips and he was able to negotiate a $75 price for the 8080 microprocessor chips.Customers would ask Intel if they could get same the low prices that MITS must be paying for 8080 family chips. Some salesmen said that MITS was getting cosmetic rejects or otherwise inferior chips. In July 1975, Intel sent a letter to its sales force stating that the MITS Altair 8800 computer used standard Intel 8080 parts and that no one should make derogatory comments about valued customers like MITS. The letter was reprinted in the August 1975 issue of MITS Computer Notes. The "cosmetic defect" rumor has appeared in many accounts over the years despite the fact that both MITS and Intel issued written denials in 1975. The launch
The induction of the Altair 8800 happened at just right time. For around ten years colleges had required science and engineering majors to take a course in computer programming; typically using the FORTRAN or BASIC languages. This meant there was a sizeable customer base who knew about computers. In 1970, electronic calculators were not seen outside of a laboratory but by 1974 they were a common household item. Calculators and video games like Pong introduced computer power to the general public. Electronics hobbyists were moving on to digital projects such as digital voltmeters and frequency counters. There were Intel 8008 based computer systems available in 1974 but they were not powerful enough to run a high level language like BASIC. The Altair had enough power to be actually useful, and was designed as an expandable system that opened it up to all sorts of applications.Ed Roberts optimistically told his banker that he could sell 800 computers and he knew they needed to sell 200 over the next year just to break even. When readers got the January issue of Popular Electronics, MITS was flooded with inquires and orders. They had to hire extra people just to answer the phones. In February MITS received 1000 orders for the Altair 8800. The quoted delivery time was 60 days but it was months before they could meet that. Roberts focused on delivering the computer; all of the options would wait until they could keep pace with the orders. MITS claimed to have delivered 2500 Altair 8800s by the end of May. The number was over 5000 by August


Cambridge Dictionaries online Cambridge Dictionaries online
Definición de "point" en inglés
noun (IDEA EXPRESSED) /pɔɪnt/
B1 [C] an idea, opinion, or piece of information that is said or written: I'd like to discuss the first point in your essay. You made some interesting points in your speech.Ideas, concepts and theoriesOpinions, beliefs and points of view the/sb's point B2 the meaning or most important part of what someone says or writes: The point is, if you don't claim the money now you might never get it. I think you missed (= did not understand) the point of what she was saying. I take your point/Point taken (= I understand that what you are saying is important). Please get to the point (= say the thing that is most important to you). He hasn't got much money, but that's not the point (= that is not the important thing).Ideas, concepts and theoriesOpinions, beliefs and points of view B1 [S] an opinion or fact that deserves to be considered seriously, or that other people agree is true: Yes, I can see your point/you've got a point there. OK, you've made your point (= told us your opinion) - there's no need to go on about it.Opinions, beliefs and points of view beside the point not important or not related to the subject being discussed: The fact that he doesn't want to come is beside the point - he should have been invited.Irrelevant that's a (good) point B2 said to show that what someone has just said is true or important: "We'll take the bus." "But we haven't got any money for the fare." "That's a point."Words and phrases expressing agreement and acceptance
(Definition of point noun (IDEA EXPRESSED) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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Using sand on roads is better than chemicals
on December 18, 2012 at 12:00 AM, updated December 18, 2012 at 12:01 AM
It has started. PennDOT and many local municipalities spread tons of chemicals to reduce ice and snow on our roads. I am not convinced they are environmentally safe.
In our development, they are often dropped in piles. They kill our grass and run off into our streams and are often spread when not necessary. Why not spread sand - not salt/chemicals? Support the local business economy, save my grass and our streams. It's less expensive and better all around.


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Habitat: Arid regions of Southern Africa
Cultivation: The cotyledon is simple to grow: It prefers full sun exposure and rather high temperatures, with the minimal above 10 ° C. Watering can be relatively abundant in summer (every 2-3 days) and then be gradually reduced in autumn and winter.
Curiosity: They grow slowly and do not produce flowers before three years of age. Their name comes from the typical shape of a spoon of its leaves, from the Greek word kòtile (cavity) because of its leaves with a hollowed shape. It has got the same root as the word "cotyledons", used in botany to indicate the two halves of the same seed or legume.
COTYLEDON KEY FEATURES
The genus Cotyledon shares with the other Crassulaceae a good spread in our country: they are very beloved plants and purchased for various reasons, ranging from cheap price, lack of thorns (they are therefore easier to handle than other genres), to the fleshy and decorative leaves. They are from South Africa.
The cotyledon have fleshy leaves, generally persistent and only in a few species they are deciduous (destined to fall in the winter season) that grow in two by two along the stem, in a position opposite to the other. The shape is generally oval or round and the color is greenish-bluish, with different nuances depending on the variety, the age and on the state of health. Even the stem is fleshy. In young plants it is alone but over the years can also be highly branched.
The flowers have different shapes depending on the species, sometimes are gathered in bunches and have an orange color more or less intense. Thy come out at the center of the rosette formed by the leaves.
VARIETY AND TYPES
Below are some of the most common varieties of cotyledon:
- Cotyledon orbiculata: leaves, large and fleshy, they have slightly red margins and grow in rosettes that are lower than the ground level. In this way the plant, with age, tends to cover the soil in which it is located.
- Cotyledon tomentosa: the leaves have a typical thick white hair and fleshy tops. It remains small (maximum 30 cm in height) but has a very fast growth if it is watered with regularity.
- Cotyledon ondulata: it is easily recognized by the particular form of the leaves: these have, in fact, a wavy edge that makes them very decorative and very suitable, for example, to be inserted inside compositions.
Other varieties that you can find in the market are:
- C. Lewisia
- C. Macrantha
- C. Ladismithiensis(comune soprattutto nella variantevariegata)
- C. Barbeyi
- C. Paniculta
- C. Teretifolia
TIPS FOR GROWING
Like other Crassulaceae, the plants of cotyledon are usually quite easy to cultivate and have a rapid growth. They are afraid of mealy bugs, but a well-ventilated area should be sufficient to avoid this risk.
Let's see how to cure cotyledon.
- Choose an exposure in full sun, preferably in a ventilated location.
- They require a rather high temperature: it must remain, in fact, above 10 ° C. During the winter months it is therefore appropriate to move them in a sheltered place, even if you do not live in a particularly cold areas.
- Watering can be abundant and regular in summer: the growth of plants will benefit. In autumn and winter it can be reduced up to be completely suspended.
- The cotyledon have no particular claims as regards the ground: but it has to be well-drained and not too heavy. It can be fertilized from May to August once every 3-4 weeks.
- The cotyledon grow rapidly and the roots, in a season, reach all the space at their disposal. For this reason it is better to pot them every spring. The first watering, after the repotting, shall be done by immersion of the vessel.
The multiplication of this plant can be done by cuttings, by seeds or by pollens. The pollen is probably the fastest and safest method. For the cuttings, it is recommended to use the period between May and June and use a stick fitted with at least 3-4 leaves.


Categories Interesting
Quick Answer: Buckingham palace address?
What is the official address of Buckingham Palace?
Area Information for Westminster, London, SW1A 1AA. This postcode is the delivery address for Buckingham Palace. This postcode in Westminster is in the London region of England.
What street is Buckingham Palace on?
Buckingham Palace Road is a street in Victoria, London. It runs from the south side of Buckingham Palace towards Chelsea, forming the A3214 road and is dominated by Victoria Station. Buckingham Palace Road.
Buckingham Palace Road in 2008
Southwest end Ebury Bridge Road
How do you address a queen in a letter?
In the body of the letter alternate between 'Your Majesty' and 'Your Majesty's' and 'you' and 'your'. The envelope should be addressed to 'Her Majesty The Queen '. Use 'Your Majesty' for the first time and subsequently 'Ma'am'. This should always rhyme with 'lamb'.
How can I write a letter to Prince Charles?
If you would like to write to Clarence House, please send a letter to: Clarence House, London, SW1A 1BA. Alternatively, you might like to keep up to date on The Prince of Wales, The Duchess of Cornwall and The Royal Family by following us on Twitter or Instagram.
You might be interested: Readers ask: Trump taj mahal now?
How do Royals address each other?
Kings and queens are addresses as "Your Majesty" when speaking to them personally and all other members of the royal family would be addressed as "royal highness." Upon second address, the queen should be called "m'am" and the king "sir." The guidelines for addressing royals when writing to them does differ from the
How can I see the Queen?
What time does Queen Elizabeth go to bed?
The queen reportedly goes to bed around midnight every night.
Is Buckingham Palace free?
Can you go inside Buckingham Palace?
How do you properly address a letter?
Things to Include When Addressing a Formal Letter First line: Full name. Second line: Company name. Third line: Street address. Fourth line: City or town, followed by the state name and zip code. The address should appear under the sender's name and should be aligned to the left.
You might be interested: Question: Climbing eiffel tower?
Does the queen respond to letters?
While Queen Elizabeth can 't actually sit down and answer every letter herself, she does give special instructions to a lady-in-waiting who she designates to respond to the fan mail. Therefore, each letter has a personalized response from the monarch.
How many letters does the Queen receive?
She will often give her response to one of her ladies-in-waiting or her Private Secretaries to send on her behalf. According to the Telegraph, the Queen receives up to 300 letters a day, an impressive amount, along with invitations from Heads of State and other official correspondence from around the world.
How should you address Prince Charles?
For male members of The Royal Family who hold the title His Royal Highness: "Your Royal Highness" on the first occasion and "Sir" thereafter.
What is a lady in waiting to the queen?
A lady-in-waiting is essentially a female personal assistant to a royal woman or high-ranking noblewoman. Because of their high profile job, many Ladies-in-Waiting are considered noblewomen themselves (with a lower ranking than whoever they work for).
How do you address Kate Middleton?
The traditional and only way to write correspondence is via the postal service. When addressing Catherine or William you must use the titles, "Your Royal Highness" or "Dear Madam".
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Banana Facts 10 THINGS YOU DIDN'T KNOW ABOUT BANANAS
Posted 19 July 2010 - 09:25 AM
1.Bananas are a human invention
Bananas as we know them are a human invention from like, 5000 B.C. Because people are picky eaters and don't like seeds. So they made hybrids until they got away with the seeds. There are still tiny little seeds in banana, but they don't work.
Look how bananas are in the wild. Weird. Ew.
2.The banana tree is not a tree
It's true! It's just a sneaky herb posing as a tree. A huge herb. Trying to be a palm tree.
3.The banana tree bears fruit once and then dies
The banana tree or herb bears only one bunch of bananas and then dies. Luckily, it shoots a new "eye" (a baby plant) before dying. This cycle lasts for about ten years, and then that particular organism dies.
Here's the banana flower. It's edible too.
4.Bananas are at risk of extinction
Because of the two items above (man-made seedless fruit, herb thing), plus the plantation type of agriculture (lack of variety = genetic weakness) the super popular Cavendish bananas are constantly at risk. One aggressive bug or disease, and bananas would be extinct. In fact, the Cavendish banana we eat nowadays —which is at high risk of extinction— is a replacement for the virtually identical banana Gros Michel that went the way of the dodo in the 1960s.
5.Bananas are great for hangover
Bananas are awesome cures for hangover! That's because, like Coke (the soda, smart ass), they're rich in potassium. Eat one before bed or just after waking up (and going back to bed).
6.It's bad luck to bring bananas on a boat
It's sailors' superstition. Some ships even ban Banana Boat sunscreen or Banana Republic clothes onboard. Nobody really knows the reason for sure. Some say it's because ships carrying bananas have to go fast so the fruit doesn't deteriorate, and as a result they cannot fish. Some say that the ripe fruit releases methane that can kill the sailors. Hypothesis apart, this makes me wonder, how the invention of the banana boat was even possible?
7.You need nuclear science to extract juice from bananas
It's awfully hard to extract juice from bananas, even though they're 80% water. Have you ever tried squeezing one? Their molecular structure is just not very squeezable. The currently available banana juice is blended banana, not squeezed banana. Which is obviously cheating. But for some reason, Indian atomic scientists are trying to find a way to extract juice from banana. Yeah, atomic scientists. From the Bhabha Atomic Research Centre. Go figure.
This image is from their website. They don't state how many bananas were used to make this much juice.
8. A banana can be a weapon
In Monrovia, Maryland, a man hold up a store with a banana. The thief snatched one fruit from the counter and began hitting the clerk, who pulled out a knife. The man with the banana split with no profit from the crime, except for the banana, which was damaged by then. And in Winston-Salem, North Carolina, a man hid a banana under his shirt and pretended it was a gun when trying to rob a store. He was caught by the store owner and ate the evidence while waiting for the cops. Strangely, he was charged with felony attempted robbery with a dangerous weapon. Not a very effective weapon, but a nutritious one.
9.Bananas are an important staple food
No surprise in being the most popular fruit, but ranking fourth as a staple food is not that expected (after wheat, rice, and corn). In some poor regions of the planet, bananas account for 70% of the dietary consumption.
10. India is the biggest banana producer in the world
In those countries, even though Cavendish is still king, there's plenty of variety of bananas. In Brazil, in any farmers' market one can find at least half a dozen types of bananas: baby bananas, plantains, purple bananas, apple bananas, silver bananas, and so on.
Posted 04 May 2011 - 03:49 PM
Over-weight: A diet consisting of bananas and skimmed milk is considered an effective remedy for weight reduction.
Keeps You Alert: It's widely known that bananas help improve brain function. Once again, it's a good idea to add a banana to your breakfast before you start the day.
Helps Quit Smoking: The combination of magnesium, potassium, vitamins A1, B6, B12, and Vitamin C help the body with nicotine withdrawal.
Got the info from this link - _URL_....0#ixzz1LOrfsVlq
Posted 12 May 2011 - 06:35 PM
Posted 10 June 2011 - 05:49 AM
1.The banana is a distant cousin to ginger, turmeric, and cardamom, and is botanically classified as a berry.
2.Alexander the Great first came across bananas in India in 327 B.C.
3.Snacking on bananas between meals helps to keep blood sugar levels up and avoid morning sickness.
4.The banana peel is edible, though perhaps not very palatable unless cooked.
Posted 13 August 2011 - 07:49 AM
Posted 17 August 2011 - 06:21 AM
Posted 15 September 2011 - 07:50 AM
Posted 20 December 2011 - 06:28 PM


Sunday, September 10, 2006
Game Review: "Panty Explosion"
Atarashii Games' Panty Explosion by Matt Schlotte and Jake Richmond is a "Psychic Schoolgirl Adventure Game." The book is 94 pages plus character sheet (designed like a student's permanent record), with front and back covers by co-designer Jake Richmond, who provides all of the game's art.
First thing's first. What's up with the title? "Panty Explosion" sounds at first like a distasteful joke. But what Richmond and Schlotte seem to have been going for is the weird phrasing and mis-translation that often happens back and forth between Japanese and English. It conveys a sense of self-awareness and pop-culture sensibility for the game, once it's clear that the title is about whacky for whacky's sake, and that it's not actually sketchy when you get to reading the book.
The layout gives lined paper background to the text, iconography in layout as well as other elements emphasizing the Japanese Schoolgirl aspect of the game, including little drawings of cats and scribbles like "Yumi <3 Toyo." Panty Explosion is designed to do one thing and one thing only—Psychic Japanese Schoolgirls. The amount to which you focus on the psychic element and how much that influences the story is left open, but most of the game's information and the game's construction is oriented towards the schoolgirl side.
In Panty Explosion, the players portray Japanese schoolgirls in junior high and high school, one or more of whom (but not all, the book recommends) are psychic, and therefore draw the attention of various demons, a catch-all term for supernatural and non-supernatural antagonists arrayed against the schoolgirls.
Student Creation and Dice Mechanics
Since Panty Explosion is very strongly character-focused, student creation takes great prominence in the book. When creating your student, cultural elements specific to Japanese schoolgirls inform the character's traits. Blood Type is regarded as a personality indicator in Japan, and therefore it will provide traits just as will your character's birth month, determining their Zodiac animal. Traits in Panty Explosion are prose traits, ex: "Tall for her age" or "Captain of the Kendo team"
The attributes known to many through Miyamoto Musashi's Book of Five Rings, the five elements (Fire, Water, Earth, Air, Void) referred to as the Godai throughout the book. The Godai are the primary attributes, each representing the student's capability in the area governed by the element. A student strong in Earth is more likely to have the ability to succeed when she is using her physical strength or stubbornness. Students choose 1 element as their strength and one as their weakness. The strength gets a rating of 5, the weakness gets a rating of one, and the other three fill in with 4, 3, and 2 dice in any order of the player's choosing.
These dice represent the pool the student can call upon in conflicts, and the degree to which the student can impact a situation through the different approaches. If a player uses all three of his student's Fire dice to kick a demon, that player will not be able to use Fire-type actions (attacking with force of words or physical might, straightforward aggressive action).
Traits are chosen in five areas: Blood Type, Zodiac, Godai, Friends and Family, and Hobbies. Traits come into play by increasing the die-type that the player rolls for the student. If a student that would normally roll d8s could bring in a trait, her roll would use d10s instead. (Panty Explosion uses 6, 8, 10 and 12-sided dice).
The size of dice a student normally uses in conflict is determined by her popularity. Players vote at the beginning of each session and each school day in the story, with one vote per player for most popular and least popular. The least popular girl rolls d6s, the most popular rolls d10s, and everyone else rolls d8s. Psychic girls, since they're weird and creepy cannot be the most popular. A die succeeds on 5 or more, so popularity ends up being very important in how easy it is for a student to succeed.
Each student also chooses a best friend and a rival. Character A can be Character B's Best friend, but Character B can consider Character A to be her rival. The rival is still a friend, but the student envies or dislikes them in some way which becomes explored in the game. In resolution, if an action is successful, it is described by the player of your student's Best Friend, if it fails, resolution is described by the Rival.
The students who are psychic have access to two powers, Levitation and Make Heads Explode. These are fairly broad in their application, based on the character's desires. Making Heads Explode is hard to control, but isn't always fatal. Each power can be used with three of the five Godai.
Each student has a personal agenda, which can be anything from 'prove to my class that I'm not as dumb as I seem' to 'keep my father at his dead-end job so I can stay in my school.' These agendas should be attainable but worth struggling for. They will help shape the story that the players tell in the game.
Running the Game
The player who provides the Demon, the school, and the non-player-student characters is called the Superintendent. Information on scene framing, demon creation, and storytelling is provided, with a major focus on helping the players explore the lives of Japanese schoolgirls in a demon-infested world. Scenes are described as being comprised of the five elements of the Godai, to break things down for ease of construction.
Superintendents are instructed to include student's personal agendas in the story that is constructed for the students, so that they are engaged on a personal level as well as the plot level.
The Demon of the story need not be an oni or other creature out of Japanese legend, it can just as easily be a government organization trying to get its clutches on the group's psychic(s), or an abusive teacher. The demon is the primary antagonist of the story. The demon gets more powerful as the psychic uses her powers, and is more powerful for each agenda left unresolved when the students confront it. The Superintendent is advised to split the demon's dice up between multiple encounters to provide several instances of conflict rather than just having the demon sweep in and kill all the students. Scenario construction is also broken down by element, as scene construction.
Examples of monster demons are given, and one third of the book is devoted to setting details to constructing a game for Japanese schoolgirls, with information about religion, hobbies, districts of Tokyo, cram schools, and more. Even if you don't use the system to play the game it's preparing you for, if you're looking to do a game set in school in Japan, this game provides invaluable information and advice for story construction.
Panty Explosion sets itself up to do one thing, and it seems like it would do it very very well. The book is focused like a laser, filled with suggestions on how to tell the stories of Japanese schoolgirls balancing between life and monster-fighting, the thematics supported from the setting description to the rules and back again.
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ICME conferences are the largest international meetings in mathematics education with sessions related to the entire set of activities in the field. The Congress attracted over 2000 mathematics educators from the international community. Plenary sessions, major lectures, Topic Study Groups, Discussion Groups, Country Showcases, and special sessions were organized to capture the breadth and depth of mathematics education across the world.
The National Science Foundation funded 53 awardees to take part in the Congress. The awardees were selected from a pool of over 600 mathematicians, university mathematics educators, and educators from K-12 schools by a Steering Committee consisting of representatives from the National Council of Teachers of Mathematics, American Mathematical Association of Two Year Colleges, Mathematical Association of America, American Mathematical Society, United States National Commission on Mathematics Instruction, and two members at large.
Each Steering Committee member chaired a particular theme group related to issues currently significant in the United States landscape of mathematics education. The awardees selected a particular theme group and as a group designed their participation at the Congress partly around events and/or sessions related to their theme. The groups met several times during the Congress to discuss what they were learning and implications for education in the United States.
The themes were
- Professional development
- Relation between research and practice
- Reasoning, proof, and proving
- Shaping mathematics education through testing
- Information and communication technology
- Applications and the mathematics curriculum
- Representation and its role in mathematics
- Preservice education.
Awardees were charged with writing a description of their experience at the Congress to reflect their perception of the Congress as a whole and/or as it related to the particular theme the awardee was following throughout the Congress. These papers are grouped according to the themes with a summary paper for that theme.
Photos from a ICME-10.
New sponsors of mathematical Internet project "icme-10": Danmarksautomaten.
Important and useful paid commercial information by local and foreign companies: dating dk København Dating Copenhagen Dating...
General partners of our web-project: Mathematics Speaks Foundation, First Mathematical Radio, WCSY.


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A decade back, I had the chance to wander a mile into a sequoia grove, and it took my breath away. They're beautiful, massive trees, and almost completely block out direct sunlight to the forest floor. Walking among them, it feels like you're stepping into another world.
But it's that complete lack of sunlight (at lower quarters) that's raised a question in my mind...and despite some research, I can't find the answer.
Here it is: For giant trees like these, I would imagine that the treetop photosynthesis is pretty critical. Packed (comparatively) close together, these giants must compete with one another for sunlight as they reach heights of over 300 feet. And since the average sequoia grove allows very light sunlight toward a tree's base, any extra photosynthesis that the tree can squeeze in must be invaluable..
But let's suppose that, halfway up a sequoia, a patch of sunlight consistently hits the tree's trunk for 20 years. No sunlight hits the trunk above or below that spot for 50 feet...but right here...in this one spot...through some accident of placement...sunlight strikes.
Does a tree have a trigger response to that sunlight, such that it will branch out in response? Or is tree branching completely dictated by a set of fixed, geometric rules...and is unwavering? Keep in mind, I'm not talking about a branch bending or leafing toward the light once it's already started growing: I'm talking about the tree creating a new branch in reaction to light's presence.
The sign of a good education is the ability to research fields unknown to you. But in this case, my literature/art/propaganda background is failing me miserably.
Is there an aboriculturalist or arborist in the house? I'd love to share the answer with everyone, if you'd like to e-mail me or post in the Sheldon forum.


text:
Tsarina Alexandra was the wife of Czar Nicholas II. She lived from June 6, 1872 to July 16, 1918.
When World War I broke out, Nicholas moved to the front lines and left Alexandra in charge of Russia. Alexandra was distracted from ruling the country, however, when her son, Alexis developed a hemophilia. The only one who was able to help Alexis was a peasant-turned-monk named Rasputin. Alexandra increasingly relied on Rasputin, who took advantage of her trust by granting postitions to his friends and causing everyone to fear him. Alexandra's misrule set the stage for the collapse of the imperial government in the March Revolution. In 1918, the Czarina and her husband and children were shot and hacked to death by communists who were led by Yakov Yurovsky.


text:
Günter Archenhold is forced out of office due to his Jewish origin by the Nazis.
The family is also ousted from the observatory, their life's work, under the most shameful of circumstances. The observatory was transferred without compensation to the possession of the city of Berlin and subordinated to the school administration.
A civil servant became administrative chairman, who was completely unacquainted with astronomy. The observatory was closed due to construction work.
Up till then, the observatory had a total number of 2,666,567 visitors, since its opening.
F.S. Archenhold died in Berlin on the 14th of October, 1939. Archenhold's wife Alice and their daughter Hilde died in the concentration camp Theresienstadt. The sons Günter and Horst found refuge and were able to emigrate to England.


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Refraction: light changes direction of propagation when entering a material with a different refractive index.
enter image description here
Does the direction of propagation of light change sharply and almost instantaneously (as shown in the diagram) or smoothly?
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2 Answers 2
up vote 2 down vote accepted
I don't understand the down vote on the OP. In order for Snell's Law ($n_1 \sin{\theta_1} = n_2\sin{\theta_2}$) to be valid, certain conditions have to be met. Usually we assume the conditions are met, and draw the simple diagrams such as yours. These represent idealizations of real situations. For example, the ideal interface is discrete, changes abruptly, and is perfectly flat, and the materials are homogenous. At a microscopic level, all real interfaces consist of meetings of molecules, so are not discrete, abrupt, nor flat, and materials are not homogeneous (they are made of atoms and molecules).
However, from a macroscopic perspective, if we don't focus attention on the microscopic, the interfaces sure look discrete, abrupt, and flat, and the material homogenous. So we expect Snell's Law to work macroscopically... as long as we don't look too close to the surface, or too closely at the molecules. And indeed, it does work. In particular, in the idealization the direction of the ray changes abruptly. Macroscopically, if we don't look too close to the surface, it does.
But your question is, really: what happens if we don't take that macroscopic view? Does the ray curve smoothly rather than abruptly change direction?
I doesn't bend. What actually happens is very complicated. I think there are two ways to look at it. In the first, the original rays spawn countless other rays in the interface region, pointing in all directions. Once we focus attention away from the interface region we find that almost all of those rays have destructively interfered, all except those that go off in the macroscopic refraction direction. Another way to look at it is to say that a ray represents a "pencil" of light having a well-defined wavelength and direction. Then, we recognize that the interface region is too small for us to unambiguously define the wave length. Thus, the concept of "ray" does not exist in the interface region.
In any event, the picture of a smoothly curving ray is not the right picture.
Well, whether or not the picture of a curving ray is correct or not depends on how closely you look, and how deeply you want to probe for an answer.
The comments point out a weakness in my answer. I tried to use the language of rays, as suggested by the diagram. Doing so will always eventually lead to trouble. "Ray" can refer to the propagation vector of a plane wave, or it can refer to a tight pencil of light, usually taken to have zero cross section in our imagination. Both of these pictures are mathematical abstractions that are ultimately non-physical.
I did not make the approximation that materials are actually continuous media. You can make that approximation and show that "rays" are curved, but that is not a correct description of what the electric field looks like in the interface region. In the continuous approximation we average the actual electric field over a volume large compared to the size of an atom, but small compared to a wavelength. One ends up with a (average) dielectric constant that is a continuous function of position. The averaged field is called the macroscopic electric field. But within the volume used to do the averaging, the actual microscopic field is varying wildly. This is why I said that either rays are propagating in all directions, or the concept of "ray" does not exist near the surface.
Let's take a different microscopic view. Light is incident on the interface. We'll model the solid as a distribution of polarizable entities, I'll call them atoms, but they could be molecules. They could be distributed regularly, as a crystal, or randomly as in an amorphous solid. The incoming light excites each dipole. Each excited dipole acts as a source of new radiation. The refracted field is the sum of the radiation of all of these dipoles plus the field of the incident radiation. At an atomic level, the field distribution is very complicated.
One can make further progress by doing the averaging procedure. We get an average field, and the fluctuations are smoothed out. This is about all we can do for the amorphous solid, because we don't know where the dipoles actually are. This results in the continuous approximation, and we predict curved rays. But that does not represent the actual electric field! We've removed much of the character by smoothing out the field.
Things are different for a perfect crystal. Here we do know where the atoms are, and we can can add all the contributions from all of the dipoles. The result, as expected, is a wave which propagates in the refraction direction. In this picture, the fields in the surface region are complicated in the way I mentioned in my original answer, and one can't describe what's going on as curved rays.
Interesting aside: when all of those individual contributions from individual dipoles are added up, we find that actually two waves are generated in the refracted material. The first propagates in the direction of the incident wave, but is out of phase with it, causing the incident wave to vanish by destructive interference. The second wave is the actual refracted wave. This result is known as the Ewald-Oseen extinction theorem.
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Can you clarify "countless other rays"? The photon is best modeled as a wavefunction, not a ray, and interference is a field effect. Quantum physics is the right tool for interface region analysis. I think it comes down to the interface imperfections being much smaller than the wavelength, hence no diffraction. On that smaller scale, what matter are average values of permittivity and permeability, and that does suggest a smooth transition. – Blackbody Blacklight Apr 26 at 14:38
Countless other rays: I'm thinking of scattering off of atom-scale fluctuations (atoms), in the way that the macro Maxwell equations follow from the micro eqns. Quantum physics: the question can be answered purely classically. QM is not needed to derive Snell's law, nor for this discussion. Photons: ditto. Imperfections smaller than wavelength: will cause diffraction. Average values: yes, that would be an alternate model midway between my microscopic picture and the abrupt ideal picture. Rays curve in that model, but it is another idealization, ignoring micro physics. Out of room! – garyp Apr 26 at 15:37
I was thinking of the wavefront, so a line perpendicular to the rays in the diagrams. I was told that, when reaching the interface, part of the wavefront is in the higher refractive region while the rest of it is still in the lower one, so that the former moves slower while the latter keeps its initial speed. This causes the ray to turn. Is this just an intuitive / heuristic explanation or is there something true? – SuperCiocia Apr 26 at 18:07
That is correct. But it doesn't answer the question "sharp or smooth". What's up for discussion is the details near the interface. – garyp Apr 26 at 19:05
The key point here is that if the physical situation is examined at very high resolution (comparable to atomic length scales) ray optics ceases to be a good approximation and you have to work directly with the field equations in the presence of matter. – dmckee Apr 27 at 0:17
Generally speaking, it's impossible to physically observe a strictly "sharp" phenomenon in physics (there still some exceptions of course). However one phenomemon can have some characteristic constants which vary much more faster compared to others phenomema.
Here, in the geometrical optics approximation, since you are only interested in what happens far from the interface, it is "ok" to describe a sharp direction change of your ray path.
But if you are zooming to see what is going on close to the interface, the ray path will always experience some gradient of the index of refraction $\nabla n$.
To calculate the ray path through a middle with a gradient of index $\nabla n$, one can use the Fermat's principle, i.e. a ray of light always takes a path with a stationary optical length $S$, so that :
$$\delta S=\delta\int_\mathcal{C}n(s)\,ds=0$$
where $s$ is the curvilinear coordinate along the ray path.
From this principle follows the eikonal equation which is an Euler-Lagrange-like equation for rays path:
$$\frac{d}{ds}\left(n(\mathbf{r})\frac{d\mathbf{r}}{ds}\right)=\frac{\partial n}{\partial\mathbf{r}}$$
where $\mathbf{r}\in\mathbb{R}^3$ are the ray path coordinates.
Solving this equation will give you the curved ray path $\mathbf{r}$ associated to the gradient $\nabla n=\frac{\partial n}{\partial\mathbf{r}}$ that the ray is experiencing for its propagation through the medium.
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Doubtful: for, e.g., an air-glass interface


The Lennard-Jones potential has the form:
The (attractive) $r^{-6}$ term describes the dispersion force (attraction at long range). Why is the power $-6$ rather than something else?
I think that it has to do with dipole-dipole interactions, but I am having difficulty working out the physics. Can you please help me?
I know that, at a distance $z$ away, the on-axis electric potential due to a dipole at the origin and aligned on the z-axis is given by:
$$V = \frac{1}{4\pi\epsilon_0} \frac{p}{z^2}$$
where $p$ is the (magnitude of the) dipole moment.
But if there is an atom nearby, the dipole will induce a dipole on the atom. The induced dipole will in turn induce a dipole on the first dipole. Is it possible to classically derive the $r^{-6}$ dependence of the dispersion force? Thanks for your time.
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 $\begingroup$ You might want o check the Wikipedia article on Vanderwaals forces: en.wikipedia.org/wiki/Van_der_Waals_force $\endgroup$ – Johannes May 1 '13 at 16:48
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 $\begingroup$ The $r^{-6}$ comes from the London dispersion force (en.wikipedia.org/wiki/London_dispersion_force) and the derivation of this is complicated. Googling for "derivation of london dispersion force" finds several promising looking articles, but they won't be easy reading! $\endgroup$ – John Rennie May 1 '13 at 17:30
 - $\begingroup$ _USER_ OK, thanks. I was thinking that the derivation would involve a dipole-dipole interaction, but I guess it is more complicated than that. $\endgroup$ – Andrew May 1 '13 at 19:57
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 $\begingroup$ _USER_ you are right it is essentially a dipole-dipole interaction but when averaging over all possible orientations the power of the decay changes from 2 to 6. $\endgroup$ – gatsu May 2 '13 at 11:00
The "simplest" classical explanation I know is the van der Waals interaction described by Keesom between two permanent dipoles. Let us consider two permanent dipoles $\vec{p}_1$ (located at $O_1$) and $\vec{p}_2$ located at $O_2$. Their potential energy of interaction is: \begin{equation} U(\vec{p}_1,\vec{p}_2,\vec{O_1 O_2}) = -\vec{p}_1\cdot \vec{E}_2 = -\vec{p}_2 \cdot \vec{E}_1 = -\frac{[3(\vec{p}_1\cdot\vec{u})(\vec{p}_2\cdot\vec{u})-\vec{p}_1\cdot \vec{p}_2]}{4\pi \epsilon_0 ||\vec{O_1 O_2}||^3} \end{equation} where $\vec{u}= \vec{O_1 O_2}/||\vec{O_1O_2}||$ and $\vec{O_1 O_2}$ is a vector going from $O_1$ to $O_2$.
Now, if the system is subject to thermal fluctuations then the dipoles can change their orientations according to a Boltzmann weight. If the time scale associated to the motion of the particles is much longer than the one associated to the dipole orientations then for each distance $r = ||\vec{O_1O_2}||$ on can trace over all the possible orientations.
The effective interaction between the dipoles is then characterized by the free energy of the system i.e. by:
\begin{equation} \mathcal{F}(r|p_1,p_2) \equiv -k_B T \ln \int \frac{d\Omega_1 d\Omega_2}{(4\pi)^2} \:e^{-\beta U(\vec{p}_1,\vec{p}_2,\vec{O_1 O_2})} \end{equation}
where $d\Omega_i$ is the solid angle element associated with the direction of dipole $\vec{p_i}$ and $\beta=1/k_B T$.
This quantity is super difficult to compute. However, if the dipoles are sufficiently far apart, their interaction energy is small and one may expand the exponential in powers of $\beta U$: \begin{eqnarray} \mathcal{F}(r|p_1,p_2) \approx -k_B T \ln \int \frac{d\Omega_1 d\Omega_2}{(4\pi)^2} && \times\\ && \:\left(1 \right.\\ && -\beta U(\vec{p}_1,\vec{p}_2,\vec{O_1 O_2}) \\ && \left.+\frac{1}{2}\beta^2 U(\vec{p}_1,\vec{p}_2,\vec{O_1 O_2})^2\right) \end{eqnarray}
The first integral $\int \frac{d\Omega_1 d\Omega_2}{(4\pi)^2} 1 $ is trivial and equal to $1$. The second integral of the potential is zero by symmetry (each dipole is as likely to be at either a positive or negative angle from $\vec{u}$ and the integral of a scalar product of two independent vectors is zero). The only remaining term is of order 2 in $\beta U$ which decays with $1/r^6$. At the end of the day we end up with something like: \begin{equation} \mathcal{F}(r|p_1,p_2) \approx -k_B T \ln \left(1+\beta^2\frac{C}{r^6} \right) \approx -\frac{C}{k_B T}\frac{1}{r^6} \end{equation} where
\begin{equation} C = \int \frac{d\Omega_1 d\Omega_2}{(4\pi)^2}\left( \frac{[3(\vec{p}_1\cdot\vec{u})(\vec{p}_2\cdot\vec{u})-\vec{p}_1\cdot \vec{p}_2]}{4\pi \epsilon_0}\right)^2 \end{equation} is a number not important in terms of physical insight.
What matters here is that the average value of the dipole-dipole interaction is zero while the first non zero term not to be zero is owing to fluctuations. This is roughly the rule with van der Waals like interactions which is that they are fluctuation driven (the same is true in the quantum case).
Remark: the previous derivation assumes that the interactions travel at infinite speed which is not true. When the limitation of the speed of light is introduced then at large distances, the van der Waals interaction decays as $1/r^7$.
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 $\begingroup$ +1 Great answer. I have a small doubt : in the equation for the free energy what happens to the internal energy part. I see that you have just indicated the entropy part. $\endgroup$ – WYSIWYG Sep 16 '15 at 5:16
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 $\begingroup$ _USER_: what do you mean by "entropy part"? I have used the usual definition that the free energy is the log of the partition function; or are you referring to something else? $\endgroup$ – gatsu Sep 17 '15 at 8:04
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 $\begingroup$ I am sorry but you are mistaken. I am taking the log of the partition function i.e. $\ln Q = \ln \sum_i e^{-\beta E_i}$ which is minus the free energy. To see this do as follows: $-\ln Q = -\ln Q -\sum_i p_i \ln p_i + \sum_i p_i \ln p_i$, where the second equality is a tautology. Now, do not touch at the second Shannon entropy term and focus on the first one. We now relate $p_i$ and $Q$ via $p_i = e^{-\beta E_i}/Q$. Upon inserting this expression into the log of the first entropy we get $\sum_i p_i \beta E_i + \ln Q$ which gives $-kT \ln Q = F = \langle E \rangle -TS$, which what I used. $\endgroup$ – gatsu Sep 18 '15 at 10:50
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We are trying to solve what we perceive as a problem with the behavior of our Samba server. Please understand we are not claiming this is a bug in Samba. It is simply different from the behavior we want.
Our Samba server is version 3.5.4 (release 68.el6) and runs under CentOS 6.0 (x86_64). We happen to use Active Directory (AD) to authenticate, but I'm not convinced this behavior is specific to AD.
What follows is a generalized statement of the undesirable behavior, with the context provided first as a sequence of events:
 1. A CIFS client establishes (and maintains) a connection to a CIFS share on our Samba server.
 2. After that connection has been established, a configuration change is made (examples provided as bullets below) which we think should immediately revoke the CIFS client's access to the connected CIFS share. For example:
 - The Active Directory user is deleted from the domain (via the Active Directory Administrative Center on the domain controller).
 - The Active Directory user is removed from the CIFS share's list of permitted users (on the Samba server host).
 - The CIFS share is deleted (on the Samba server host).
Here's the undesirable behavior. As long as the CIFS client maintains the existing connection to the CIFS share, access to that share is not revoked. That is, the user continues to have the same access to the share as they did when the connection was first established. FWIW, we believe this behavior is by design.
The desired behavior is for access to be revoked as soon as "the configuration change" pertinent to access rights is finalized. Disconnecting the affected client session(s) is acceptable and appropriate, but disconnecting other sessions is undesirable.
I would like to get your ideas toward an approach that will yield the desired behavior. Perhaps this is as simple as changing our Samba server's configuration; we have not found any configuration parameters that appear relevant to this behavior. It appears the art of detecting that access has been revoked is the most difficult part of all this.
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1 Answer 1
I'm pretty sure this isn't possible at the moment, at least not using the functionality built into Samba itself.
A workaround could be something like a cronjob which regularly checks that all the smbd processes on a machine are from valid users, by parsing the output of the smbstatus utility to check what users are logged on and what processes are serving them, and verifying those processes against the users in AD. You can then use that information to kill any processes for users who are no longer valid.
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Textbooks use simple images to illustrate many of the perceptual cues that give rise to the impression of depth. These images allow the reader to focus on one particular cue at a time and to see how the impression of depth arises from that cue alone. In fact, each topic in this tutorial is headed with a simple drawing illustrating the depth cue. For example, the first depth cue to be discussed here is interposition which is the partial blocking of a more distant object by a nearer object. Check the small figure with the word interposition at the beginning of this page. There are two rectangles with the farther rectangle, lower and to the right, partially obscured by the nearer one, right? Well, actually both rectangles are at the same distance (the distance of the screen from your eyes). It is the interposition, overlap, that causes the sense of depth to arise. Usually the impression of depth caused by interposition alone is not very strong.
For another illustration of interposition, look at the image below. Here are three figures. They start out appearing at the same depth when they are not overlapped. When the move together to overlap, then they appear to be a different depths, with the figure on the left appearing nearest.
The virtue of studying depth cues in art rather than in simple drawings is seeing the cues in action, as it were. But the amount of depth that is perceived is not relevant, i.e., the sole purpose of these simple illustrations is to show that depth can be generated from the depth cue and not how that depth cue can be used to depict a realistic depth scene. In art, on the other hand, the amount of depth that is perceived is extremely important. The representation of depth has a specific goal not found in the simple drawings. Take the example of interposition. As stated above, the impression of depth that generally arises from interposition is quite minimal, but when the depth range that is being depicted is quite small, overlap may become a very important depth cue as in the painting by Sandro Botticelli below:
Madonna of the Magnificat by Sandro Botticelli.
Notice the foreground figures, which are all that are important for our present purposes. Here relative size and even relative height play little role in giving the depth order of the various figures (all the figures are roughly the same level and same size). Shadowing plays an important role in giving each of the figures their sense of three-dimensionality, but to tell who is in what position relative to another, the principle cue is interposition.


text:
Freshman/Sophomore Seminar - Exploring the Short Story in the Philippines and Indonesia
In both the Philippines and Indonesia, the short story is an important vehicle for artistic, emotional and socio-political expression and experimentation. This seminar will introduce students to some of the major contemporary themes, including romance, resistance, gender, and the challenges of modernization and the new global order. The comparative perspective will enrich our understanding of the strong narrative traditions of these two important countries of island Southeast Asia. This seminar may be used to satisfy the Arts and Literature breadth requirement in Letters and Science.


text:
Let's say I would like to communicate with my friend using asymmetric/public-key encryption, e.g. RSA.
(Note: I do realize that in practice this is done through an intermediate symmetric key, but this question assumes we only use asymmetric encryption.)
Say I try to do this: I slice up my data into 2n-byte blocks (
padding with zeros [edit: padding appropriately] if necessary), append the block index to the block (to prevent the same plaintext from turning into the same ciphertext), then use my friend's public key to encrypt each block separately.
Is this a secure scheme, or does the fact that I'm re-using the key make it susceptible to some kind of attack? If so, is it used in practice in any existing algorithms? If not, is there any way to make it safe, aside from using a symmetric key?


Wednesday, December 7, 2011
Indexing an Array with a Variable
Sometimes, in the context of a mathematical program, someone wants to use a variable $x$ to index a vector $y$, as in \[z = y[x].\] As a starting point, we should assume that $x$ is an integer variable whose domain equals, or at least is a subset of, the index set of $y$. If you try to set $z=y[2.71828]$, or $z=y[5]$ when $y$ is indexed by ${1,\dots,4}$, you should expect Bad Things To Happen.
With that stipulation, $z=y[x]$ poses no problem in a constraint program. It cannot, however, be expressed directly in a mathematical program. If the domain of $x$ is not too large, it can be implemented somewhat obliquely in a mathematical program using binary variables.
Let's assume that $y$ is indexed over $1,\dots,N$ (with $N$ known at the outset), and that $y$ is a parameter. (We'll treat the case where $y$ is a variable in a minute.) Create $N$ binary variables $x_1,\dots,x_N$ and add the constraint \[x_1+\dots+x_N=1,\] which makes $\{x_1,\dots,x_N\}$ a type 1 special ordered set (SOS1). Then define $z$ via \[z=\sum_{i=1}^N y[i]*x_i.\]
You can do exactly this when $y$ is a vector of variables, but it adds a nonconvex quadratic constraint to the model, which likely prevents you from finding a guaranteed optimum, and greatly restricts what algorithms/software you can use. If we know a priori lower and upper bounds for $y$, say \[L_i \le y[i] \le U_i \forall i\in {1,\dots,N}\] with $L_i$ and $U_i$ parameters, we can add the $x_i$ as above and use the following set of constraints to define $z$: \[\begin{eqnarray*}y[i] -z \le (U_i - \hat{L})(1-x_i) \forall i\in {1,\dots,N}\\ y[i] - z \ge (L_i - \hat{U})(1-x_i) \forall i\in {1,\dots,N}\end{eqnarray*}\]where $\hat{L}=\min_{i=1,\dots,N} L_i$ and $\hat{U}=\max_{i=1,\dots,N} U_i$.
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