text:
In order to better understand the potential for both policy and technological improvements to aid carbon abatement, long-term historical information on the time-path of transition from more traditional to cleaner fuels is useful. Knowing how this varies by socio-economic, demographic and geographic factors is also crucial in designing targeted policies. This research examines the timing and determinants of residential gas connections at area level within Ireland. We merge a unique dataset on gas network roll-out over time, with other geo-coded data and employ an instrumental variables technique in order to simultaneously model supply and demand. Results indicate a non-linear relationship between the proportion of households using gas as their primary means of central heating and the length of time the network has been in place in each area. Proximity to the gas network, peat bogs, and areas which have banned the consumption of bituminous coal also affect gas connections. Variations in socioeconomic and dwelling characteristics at area level can also help explain connections to the gas network.
Gas network Residential heating Spatial economics Instrumental variables estimation


power transformers and motors.
 - G.P.O. used an 803 at their Dollis Hill Research Labs for electronics design and telephone network simualtions.
 - G.P.O. used an 803 at their Goonhiily Downs satellite earth station for calculating satellite passes and punching tapes to steer dishes.
 - Corah Knitware in Leicester UK used a pair of 803s for telephone order processing and production planning.
 - Thornber Farms in West Yorkshire UK used an 803 to process egg production data for breeding of chickens. [5]
 - Vickers da Costa, a London stockbroker, used an 803B for trade processing and payroll from 1961 to 1966 when it was replaced with a National Elliot 4300.
 - The RAF No1 Radio School RAF Locking used an 803 in 1968 to train the first RAF Computer Technician Apprentices.
A small number of 2nd hand 803s found their way into schools in the UK.
 - Felsted School once had 2 Elliott 803 machines, nowadays only the control console remains, it is hung up in the corner of one of the school's current IT rooms as a reminder to why the room is named "Elliott" [6]
 - Loughborough Grammar School were given the machine from Brush Electrical Machines mentioned above. [7]
 - Banbury School had 2 Elliott 803Bs, one with 4096 memory and tape, and one with the 8192 memory. They taught Elliott Autocode as a primary language but also had an ALGOL compiler. The machines last ran in 1980 when they were replaced by a classroom full of BBC B's. They also acquired the machine from Loughborough University for spares.
 - Mill Hill School has an Elliott 803 with 8192 memory in the 1970s. It had 5-track paper tape reader and printer but no other I/O devices. The school had Elliott 803 autocode and Algol compilers.
 1. ^ a b Version 3, November 2011 E3X1, Delivery lists and applications of the Elliott 800 series and 503 computers.
 3. ^ Elliott 803 news, more tidbits from the archive and several generous donations to boot, 19 September 2010, The National Museum of Computing
 4. ^ Bill Purvis (5 October 2005). "Elliott 803 Algol".
 5. ^ Science And The Egg Aka Chick Automation: Science Aids The Egg, Issue Date: 12/02/1962 - British Pathé
 7. ^ Elliott 803, The first computer I programmed, Created 1 December 2003
 - Adrian Johnstone, The Young person's Guide to... The Elliott 803B, Resurrection (Bulletin of the Computer Conservation Society) 1 (Spring 1991) [1]
 - Tony Hoare, The Emperor's Old Clothes, Communications of the ACM 24 (February 1981)
 - Elliott Brothers (London) Ltd., Scientific Computing Division, A Guide to Programming the 803 Electronic Digital Computer (June 1962)
 - Pathe News Reel, SCIENCE AND THE EGG, [2]
 - The first computer I programmed [4]
External links[edit]


text:
Due in no small part to the Herculean efforts of Thomas Bayes, a researcher arguably hundreds of years ahead of his time, a seminal contribution to multiple scientific fields is imminent. This paper investigates the significance initial conditions and the relationship shared with conditional probability via the Bayes theorem, via autocorrelation (trend) on a fractal basis to improve the odds of winning on any investment from 50% – 66%, 66% – 87% and 87% – 94%. Nevertheless, the intention of the author is to inspire research beyond the confines of financial economics and into every field where continuous data are prevalent. The author requests a US patent for the Bayes – Poincaré Financial Algorithm, following precedent set by the patent granted to Google for the PageRank Algorithm.
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Blade Path and the Ideal Blade
Defining and studying an "ideal blade" has informed our blade innovation over the years and has led to the development of our most efficient blades: the Smoothie2 Vortex Edge and Fat2 blades.
The Typical Blade Path During the Drive
Contrary to how it might look, an oar blade does not travel in a continual arc through the water as represented in Figure 1. This would only be true if the boat were tied up to a dock. The typical path of the blade, as the boat moves past the point of entry, is the complex movement shown in Figure 2.
Figure 1: The assumed blade path.
Figure 2: What the blade path is typically.
Below, the blade path is illustrated by an image taken from an overhead video of an actual oar in the water.
We define this typical blade path as having four distinct phases:
 - Phase 1: Forward Blade Motion—The blade moves significantly forward, toward the finish line.
 - Phase 2: Outward Blade Motion—The blade moves outward, away from the boat.
 - Phase 3: Backward Blade Motion—The blade moves backward, toward the starting line.
 - Phase 4: Inward Blade Motion—The blade moves inward, toward the boat.
Having identified the typical blade path, we can now examine how a theoretical ideal blade would move and what this might tell us about how to best harness the rower's effort during the drive.
The Ideal Blade
We define the ideal blade as having:
 - Zero slip perpendicular to the blade surface.
 - No resistance to movement in line with the shaft; in other words, it would glide.
 - The ability to rotate in the water. We will define the point of rotation as the point where the blade and shaft join.
Developing a New Blade Path
Keeping in mind that boat movement influences blade path, and that blade movement is defined by the characteristics of the ideal blade, we plotted what the ideal blade path would be. We have assumed that the boat speed would be the same as for the typical path, so the position of the oarlock is the same as in each frame of the typical path diagram. Each new oar position was then plotted between the oarlock and the new blade position as defined by our ideal blade. See Figure 3.
Figure 3. The ideal blade path
In Figure 4 we have superimposed the ideal path (green) and the typical path (red) with the blades removed for clarity.
Observation 1: Shorter Outboard Length
Our first observation is the handle positions noted by the circle. It appears as though the ideal oar has not completed the stroke. To adjust for this we shortened the outboard length used with the ideal blade and re-plotted as before. This is illustrated in Figure 5.
Figure 4
Figure 5
Observation 2: Slower Rotation at Beginning of Drive
After superimposing the two blade paths, we noted that at the beginning of the drive, the ideal oar rotates more slowly than the typical oar and then speeds up in the second half of the drive.
To the rower, this means the ideal blade will feel heavier early in the drive and feel lighter after the oar reaches perpendicular. From a physiological standpoint, it makes sense to maximize blade efficiency at the same point of the stroke when the rower is using his or her large muscles to power the drive. From the perpendicular to the finish, only the upper body and arms are engaged, so it also makes sense that the load becomes lighter and handle speed increases in this phase of the drive.
Observation 3: Less Work Required to Move the Same Speed
Once the ideal oar was shortened, we were able to achieve the same catch and finish angles and the same amount of drive time as that of the oar in the typical blade path. The boat also moved the same distance, indicating that it moved at the same speed regardless of which oar was used. Because the outboard lever is shorter in the ideal blade path, the force on the handle is less, which means that less work is required to move the boat the same speed. This also means that if the same force is applied on the handle, the force on the end of the shorter oar will be greater. In other words, the rower will get more speed for equal effort.
Less effort, same speed
Equal effort, more speed
Observation 4: Less Slip
By observing blade movement during oar rotation, we noted that the ideal blade slips less. Note the image below. The slip pattern of the ideal blade is on the right. Of course, this is expected by definition of the "ideal blade."
We also see that the typical blade slips more during the first part of the drive and doesn't slip enough during the last part of the drive. The area shaded red indicates a backwatering condition where the part of the blade near the shaft produces some negative thrust, or drag. This is created by the combination of blade rotation and forward movement of the boat.
Typical Blade
Ideal Blade
Pursuing a Blade that Approaches the Theoretical Ideal
With an increased understanding of what would produce an efficient blade, we set off to design a new blade by targeting specific blade features.
 - Surface area—Increased surface areas tend to resist slippage perpendicular to the blade surface.
 - Curvature/hook—Flatter blades generate a heavier feel earlier in the drive, allowing for slower rotation.
 - Tip characteristics—Vortex generating features reduce slippage perpendicular to the blade surface.
 - Tip shape—Tapered blade edges create a force on the back of the blade, increase lift, and reduce slip, much like the delta wing effect in aeronautics.
We built these features into our Smoothie2 Vortex Edge and Fat2 blades, making them the most efficient blades we offer. Read more about how we conduct on water testing.


What are the requirements to get a government job?
Quick Answer
The requirements to get a government job include citizenship, security clearance and registration with the Selective Service System for male applicants. In addition, requirements unique to the job being applied for, including education, experience and job-related qualifications, must be met.
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Full Answer
Most federal jobs require the applicant to be a citizen and a few also need security clearance. However, unless the applicant is offered a job position that demands security clearance, the government will not ask for or bear the expense of a background check.
Additionally, male applicants who are above 18 years of age and were born after December 31, 1959 should be enrolled in the Selective Service System to be eligible for applying for a government job. Alternatively, they should be exempted from this requirement.
Government jobs also require the applicant to have a high school diploma, college or university degree and work experience that is relevant to the job being applied for.
Further, candidates with special job-related qualifications such as training courses and skills such as computer knowledge, language and machinery use are preferred over others if the job demands these. Preference is also given to job applicants who have earned some awards and honors such as publications and performance awards pertaining to the job. Some jobs also require the applicant to possess certain licenses and certificates.
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text:
Planning During the Internship: A Study of the Planning Practices of Preservice English Teachers
Hessong Grove, Rebecca M.
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This collective case study investigated the planning practices of six English education interns during the full time internship, including planning for edTPA. Research and professional standards emphasize the importance of planning, as it undergirds every aspect of what happens in a classroom. By understanding how interns learn to plan, teacher educators can better facilitate interns' development of planning skills. Using activity theory as a theoretical framework, this study describes how interns' planning practices changed over the course of the internship and identifies factors that influenced changes. Data sources included lesson plans, interviews with interns and mentors, and edTPA lesson plans. Findings showed most interns did not write detailed daily plans, but those who did experienced fewer planning and teaching struggles. Communication and feedback from the mentor were major factors in creating successful plans and planning routines. Three of the interns began writing more detailed plans to improve their teaching, motivated by a desire to be more organized and effective. All interns wrote detailed, formal plans for edTPA, and these plans included elements that were not part of typical written plans, such as differentiation and formative assessment. Other areas of change included increased planning for scaffolding and addressing students' confusion. Graduate interns expressed increased confidence in planning student-centered lessons. Factors that influenced such changes included experience, mentor guidance, and support from a methods course. Interns also drew on their increasing knowledge of students and district curriculum to plan relevant lessons. Interns consistently planned at the whole-class level, with little evidence of planning for individual learning. This study has implications for teacher educators aiming to strengthen candidates' planning practices. Programs must facilitate proactive mentoring and structured co-planning. Pre-service coursework should help candidates integrate student-centered pedagogy, formative assessment, and differentiation into lesson plans. The impact of internship length and undergraduate vs. graduate program structures must be investigated further. Finally, this study indicates that planning for edTPA was educative for interns. This, along with other findings, suggests that more formal planning can improve intern learning and program coherence.


text:
Place: Large Lecture Room – CVC
Affiliation: Humboldt Fellow, German Cancer Research Center Heidelberg, Germany Dep.of C.S and Engineering, Jadavpur Univ. India
Clustering, a popular exploratory data analysis tool, attempts to partition a given data set into a number of cohesive groups such that patterns that belong to the same cluster are much more similar to each other than patterns that do not. In many situations, it is difficult to assign a point to just a single cluster. Hence in fuzzy clustering, each point is provided a membership value, indicating its belongingness, to multiple clusters.
Often, the clustering problem is mapped to one of searching for an appropriate number of suitable partitions such that some goodness measure is optimized. Consequently several researchers have been actively investigating the effectiveness of genetic algorithms for clustering, since it involves appropriate parameter selection and efficient search in complex and large spaces in order to obtain robust and close approximate solutions. Evidently, it is difficult to define a single measure of cluster goodness. Hence in recent times, the clustering problem has been posed as one of multiobjective optimization, where multiple, often conflicting, objectives are simultaneously optimized. In this talk we will deal with the problem of multiobjective fuzzy clustering using some recently proposed multiobjective optimization techniques. Since such methods provide a set of Pareto-optimal solutions, a novel way of integrating these with support vector machines will be described in order to arrive at a consensus solution.
Some real life applications of the said multiobjective fuzzy clustering method to gene expression data as well as remote sensing images will be demonstrated.


Take the 2-minute tour ×
It appears that only Partial Homomorphic Encryption(P.H.E.) is practical for modern day (2011) use. However I'm having difficulty locating libraries (FOSS or otherwise) that enable me to leverage this technology.
El Gamal is an example of an algorithm that does PHE, but the wiki page doesn't clearly explain what blind math operations are supported and how to implement them.
Potential Use Cases
A PHE is something that can be used abstract to offload mathematic operations to a 3rd without that party ever knowing what the underlying value is. e.g. x+y=z can be performed and it will have a valid encrypted result, but all 3 values are never known in unencrypted format to the third party. This is beneficial to protecting stock market analysis data, PII, or anything considered proprietary or confidential.
So, what encryption algorithms exist and what libraries exist that allow me to operate on the encrypted data? Samples of operations I'm interested in include
 - Addition and Subtraction
 - Multiplication or Division
 - Comparisons (is encrypted X greater than encrypted Y)
 - A technique that will allow me to compare the binary/encrypted ASCII version of the word "Ap" and do a Contains() or StartsWith() with the encrypted version of "Apple"
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4 Answers 4
up vote 8 down vote accepted
El Gamal encryption allows for multiplication. This occurs within the group on which El Gamal runs; hence you are multiplying numbers modulo a given prime, not "plain" integers. If you can multiply you can divide (inversion in a group of size q is done by raising to the power q-2, so this is a matter of performing some multiplications). El Gamal is implemented in libgcrypt (used in GnuPG) but you would have to do the multiplications yourself (El Gamal is used in the OpenPGP format, but not for its homomorphic properties).
Paillier encryption allows for addition. There again, addition occurs in a finite group (here, numbers modulo n, a big composite integer). I am not aware of implementations of this system in widespread generic crypto library (my non-awareness does not imply inexistence, though) but a simple google search finds a few Java-based implementations (Java offers BigInteger, making implementation of such systems easy).
An important point is that such encryption systems are randomized: for a given plaintext, there are many possible ciphertexts. Thus, you cannot know whether two ciphertexts correspond to the same plaintext or not. A fortiori, they do not allow comparisons (order within a finite group is not well-defined anyway). Note that a comparison method would not be compatible with a secure asymmetric encryption: anybody could encrypt chosen values to guess the encrypted data with a dichotomic search. On a general basis, the key words for that are "data mining". Performing data mining on encrypted data is a widely unexplored field, with substring matching as a kind of Holy Grail. Briefly stated, there is nothing immediately applicable there.
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At this link stanford.edu/class/cs259c/lectures/bgn.pdf it is stated that ElGamal supports additions as well if implemented with elliptic curves.Actually you can have ElGamal homomorphically evaluated on its aditions if you raise the message to a base, but then you don't need the second ciphertext and the scheme seems as Pailier – curious Mar 29 '13 at 9:23
There's a catch: we call "addition" the operation on curve points, but that's just a tradition. ElGamal works over a group and is homomorphic with regards to the group operation, regardless of whether you choose to call it "addition" or "multiplication" or "frobnication". What we want is a wait to get additions on integers, which ElGamal does not provide, unless you accept to do compute a discrete logarithm at the end (as is done in voting schemes, where the tally is within a rather small range and can thus be searched for exhaustively). – Thomas Pornin Mar 29 '13 at 13:08
An example of practical use of PHE (and El Gamal in particular) is Helios Voting. With it you can publicly store encrypted voted ballots in the cloud, and also allow the public to both add them up to confirm the vote counts for each candidate, and to check that their own vote was indeed included in the total, without having a receipt that could prove how they voted to a third party.
It is open source. You can get the source code (based on Python, JavaScript, Django) here:
I don't know how easy it would be to pull pieces of Helios out into a reusable library, but it is one place to look.
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_USER_ nailed it. There are schemes that support addition, and schemes that support multiplication (but no practical scheme that supports both). There is no scheme that supports comparison, as that would be incompatible with security.
There are also schemes that support checking whether the encrypted text contains a particular keyword (e.g., this paper), though the threat model and what is accomplished is a bit different. These schemes are oriented at situations where you yourself are the one who uploaded the data, and you remember the crypto keys, and they're focused on read-only (or read-mostly) data sets. They also reveal information that could be used for traffic analysis (e.g., the number of hits on the keyword and their location in the encrypted file).
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You can have comparisons with an order preserving encryption scheme whose security is strongly debated here and here. Also section II-A of that describes some weaknesses of OPE
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Any links to the controversy (if not in that white paper) would be appreciated. – LamonteCristo Mar 22 '13 at 12:00
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text:
Wind Energy Guide for County Commissioners
One of the key stakeholders associated with economic development are local government officials, who are often required to evaluate and vote on commercial wind energy project permits, as well as to determine and articulate what wind energy benefits accrue to their counties. Often these local officials lack experience with large-scale wind energy and need to make important decisions concerning what may be a complicated and controversial issue. These decisions can be confounded with diverse perspectives from various stakeholders. This project is designed to provide county commissioners, planners, and other local county government officials with a practical overview of information required to successfully implement commercial wind energy projects in their county. The guidebook provides readers with information on the following 13 topics: Brief Wind Energy Overview; Environmental Benefits; Wind Energy Myths and Facts; Economic Development Benefits; Wind Economics; The Development Process; Public Outreach; Siting Issues; Property Tax Incentives; Power System Impacts; Permitting, Zoning, and Siting Processes; Case Studies; and Further Information. For each of the topics listed, the guidebook provides an introduction that identifies the topic, why local government should care, a topic snapshot, how the topic will arise, and a list of resources that define and assess the topic.
This information was last updated on 10/31/2006

source: HuggingFaceFW/fineweb-edu


Definitions for hiatushaɪˈeɪ təs
This page provides all possible meanings and translations of the word hiatus
Princeton's WordNet
 an interruption in the intensity or amount of something
 2. hiatus(noun)
 a missing piece (as a gap in a manuscript)
 3. foramen, hiatus(noun)
 a natural opening or perforation through a bone or a membranous structure
 1. hiatus(Noun)
 A gap in a series, making it incomplete.
 2. hiatus(Noun)
 A gap in geological strata.
 3. hiatus(Noun)
 An opening in an organ.
 Hiatus aorticus is an opening in the diaphragm through which aorta and thoracic duct pass.
 4. hiatus(Noun)
 An interruption, break or pause.
 5. hiatus(Noun)
 A vacation, break from work.
 The band took a hiatus for three months.
 6. Origin: From hiatus, from hio.
Webster Dictionary
 1. Hiatus
 of Hiatus
 2. Hiatus(noun)
 an opening; an aperture; a gap; a chasm; esp., a defect in a manuscript, where some part is lost or effaced; a space where something is wanting; a break
 3. Hiatus(noun)
 the concurrence of two vowels in two successive words or syllables
 4. Origin: [L., fr. hiare, hiatum, to gape; akin to E. yawn. See Yawn.]
 1. Hiatus
 In phonology, hiatus or diaeresis refers to two vowel sounds occurring in adjacent syllables, with no intervening consonant. When two adjacent vowel sounds occur in the same syllable, the result is instead described as a diphthong. The English words hiatus and diaeresis themselves contain a hiatus between the first and second syllables.
Chambers 20th Century Dictionary
 1. Hiatus
 hī-ā′tus, n. a gap: an opening: a chasm: a break in continuity, a defect: (gram.) a concurrence of vowel sounds in two successive syllables. [L.,—hiāre, hiātum, to gape.]
 1. Chaldean Numerology
 The numerical value of hiatus in Chaldean Numerology is: 2
 2. Pythagorean Numerology
 The numerical value of hiatus in Pythagorean Numerology is: 6
Sample Sentences & Example Usage
 1. Hoesung Lee:
 There is no hiatus (in global warming). Multiple lines of evidence suggest that the earth is warming.
 2. Richard Slark:
 I believe we are looking at a 2-3 year hiatus in those large-scale energy projects where financing would be international.
 3. Kevin Roberts:
 Chris Christie has decided to take a hiatus from Chris Christie work in the finance world to spend more time with Chris Christie family and young children.
 4. Kevin Roberts:
 Mrs. Christie has decided to take a hiatus from her work in the finance world to spend more time with her family and young children, she recently resigned her position as a managing director at Angelo Gordon.
 5. Ram Ben-Barak:
 The Americans are satisfied because, in their thinking, diplomacy succeeded. But we are very, very worried and the Gulf countries are very, very worried and it is absolutely clear to everyone that this hiatus is utterly temporary.
Images & Illustrations of hiatus
Translations for hiatus
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Scan for.PCH File Extension Errors | What is the.PCH File Extension? | Repair.PCH File Errors
Run a Free Scan to check for PCH related errors.
What is the.PCH File Extension?
.PCH File Extension Description:
Microsoft Visual Studio uses The PCH file extension. Visual Studio contains a set of tools and processes that are used to build programs from source code written in programming languages. It can be used to create GUIs (Graphic User Interfaces), consoles, web sites, Windows Forms tools, web applications and web service functions. The program can support several programming languages such as C, C++, VB.NET, and C#. The program includes a code editor, a debugger, a designer for GUI software, class designer for creating object blueprints, a designer for database structures and a web designer. There are also several add-ons and plug-ins available that can be added to the program to provide additional functions. The program has language specific versions, particularly Microsoft Visual C++.
The Microsoft Visual C++ version of the program is a compiler program for the languages C and C++. Compilers are used to create source code files out of written program script. The program includes all the tools of the generic program, except they are specifically designed for the C and C++ programming language. This version of the program uses the PCH file extension. The file extension.pch is attached to header files. Header files with the.pch file extension are attached to source code files that are compiled by the program. Source code files contain programming scripts, which are used to create processes or objects. Source code files can then be run by a debugger program to check for errors in the script, linked together to form a library, DLL (Dynamic Link Library) or an executable file.
Files with the PCH file extension tell other software development programs what resources the source code file needs. The PCH file extension is used to store descriptions of the process stored in the source code it is attached to. These files are also written in either the C or C++ programming language.
The Pixeur program also uses the PCH file extension. The program is used to check and identify all the colors in a computer screen. The software identifies the Hex, Long, RGB and Color Value of any hue. Pixeur can also store the history of all the colors selected by the user. These colors are stored in files with the PCH file extension. These files are called Pixeur Color History files.
Author: Microsoft Corporation (,Microsoft Visual Studio),, Veign (,Pixeur),
Author URL:,MicrosoftVisualStudio),,,Pixeur),
Related Applications: Microsoft Visual Studio C++, Pixeur
Common Path: N/A
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What Causes.PCH files Errors?
.PCH files errors are potential severe Windows file system errors and are caused due to a faulty registry entry that needs to be repaired right away to prevent additional corruption in other applications and/or hardware. Dangers include device damage, blue screen errors and fatal crashes.
Symptoms of.PCH files Errors:
.PCH files errors produce many symptoms, including: computer hangs on start up or shut down, softwares halt, diminished personal computer performance, case speaker beeping, trouble accessing documents, sluggish behaviour and trouble installing software.
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text:
Anticipation and Time: The Greatest Warriors of Decisions?
What is the nature of time? Not the space-time of general relativity, but the time we perceive. Which factors induce us to choose $100 today over $200 in a year? Is it the desire for immediate gratification? If so, why do we prefer to store a bottle of expensive champagne instead of consuming it right away? These are some of the questions that will be answered in this blog.
Of the various assumptions underlying economic analysis of intertemporal choice (choices differing in payoffs and time), perhaps, the assumption of preference for today over tomorrow is the most widespread and non-controversial one. It makes logical sense to appraise more value to $100 today compared to $200 at a later time, since we do not know what goods and services can be bought next year with that amount. Our short-term preference for positive events bespeaks that we are maximizing our utility through the elimination of uncertainty. Likewise, we have a long-term preference for events incurring us costs, i.e. preferring paying $150 in 1 year over $100 today. However, it requires little effort to think of examples of behaviour in which the converse is apparent. The pleasurable deferral of a vacation, the speeding up of a dental appointment, and the prolonged storage of wines are all instances of this phenomenon. Therefore, the traditional economics approach misses an imperative element of intertemporal choices: anticipation of future events.
Anticipation in the Form of Present Utility
It is unequivocally correct that individuals, in their choices, attempt to attain the highest utility. However, the key is to understand that the sensation of the present is affected by the anticipation of the future. We often get positive feelings from anticipating an imminent event. In an experiment conducted by renowned behavioural economist, George Loewenstein, subjects were asked to specify the amount that they would pay now to obtain or avoid each of five outcomes, which were further grouped into time delays. The outcomes were: (1) obtain four dollars; (2) avoid losing four dollars; (3) avoid losing one thousand dollars; (4) avoid receiving a non-lethal 110-volt electric shock; and (5) obtain a kiss from the movie star of your choice. Time delays were: (1) immediate; (2) in twenty-four hours; (3) in three days; (4) in one year; and (5) in ten years. The subjects were also told that the outcomes were certain to occur at the designated time. The results are illustrated in the following graph.
It can be inferred that the two non-monetary items, the kiss and the shock, exhibit unusual patterns. The short-term preference implies that individuals would prefer to obtain positive outcomes as soon as possible. This prediction, however, is contradicted by the kiss item, for which, the highest value appraised to occurrence was 3 days. In like manner, the economist assumption asserts that negative outcomes are delayed whenever possible. Yet, in the shock outcome, subjects preferred to pay slightly more to avoid a shock that was delayed by 3 hours than 3 days.
Explaining the Phenomenon
The ostensibly contradictory phenomenon becomes unambiguous if we consider the affect of anticipation of future events on the present utility. In the experiment, the most valued time for the kiss was three days, as there was also a value from expecting the event to occur. Individuals actually increased their inner pleasure through savouring utility of both the event and the expectation of the event. Likewise, in the shock case, a negative utility arises from expectation of the event, exacerbating the total pain felt by the individual. These negative anticipatory feelings can be acute; researchers have found that in some cases the anticipation of an event may be worse than the event itself.
Evolutionary biology traces the source of this tendency to the aspects of innate mammalian system. In the acknowledged fight-or-flight response system that prepares the body to stay and fight or to flee, negative anticipation of a future event induces people to take the flight response. However, in the cases which the drastic future event cannot be avoided, the individual is propelled to fight now, as in the experiment subjects preferred the shock now instead of having it in three days.
In essence, the determinants of intertemporal choices are not limited to time preferences, and the feelings associated with expectation of a future event further affects individual choices. As the avant-garde economist Alfred Marshall remarked, "When calculating the rate at which a future benefit is discounted, we must be careful to make allowance for the pleasures of expectation."
Caplin, A. and Leahy, J. (2001). Psychological Expected Utility Theory and Anticipatory Feelings. The Quarterly Journal of Economies, 116(1), pp. 55-79.
Loewenstein, G. F. and Prelec, D. (1992). Anomalies in intertemporal choice: Evidence and Interpretation. The Quarterly Journal of Economies,107(2), pp. 573-597.
Loewenstein, G. F., Weber, U. E., Hsee, K. C. and Welch, N. (2001). Risk as Feelings. Psychological Bulletin, 127(2), pp. 267-285.
Ortony, A., Clore, G. and Collins, A. (1988). The Cognitive Structure of the Emotions. Cambridge: Cambridge University Press.


Five important facts about the Black Sea
Five important facts about the Black Sea
1. How clean is the water in the Black Sea?
The EU EMBLAS project has carried out a study about presence and concentration of chemical pollutants in the Black Sea (with regard to water, sea bottom and living organisms). Specifically, the project examined the substances recognised by the EU as mandatory for control: persistent organic substances, pharmaceuticals, pesticides, biocides, flame retardant substances, industrial chemicals and their degradation products.
Out of more than 2,100 known pollutants, 124 have been found in the water samples. Contaminants included petroleum products from maritime transport, water repellents used in production of paper cups and packaging, mercury and dioxins. Pesticides used against weeds and insecticides such as fipronil, which is particularly toxic to bees, have also been found. The highest concentration of pesticides was recorded off the coast of Georgia.
Traces of pharmaceuticals for treating arrhythmia and hypertension, as well as chemicals contained in plastic bottles and sunscreen, which are harmful to marine inhabitants, were found as well.
Compounds of harmful organophosphates which could be found in almost all products we use daily, like textiles, furniture, computers, etc., were recorded at every monitoring station. The highest levels of concentration of these substances were discovered in Danube Delta, the river Dniester and in the Georgia's coastline waters.
If the quantity of chemicals exceeds a certain level, they become destructive to all living organisms and disrupt the reproduction and development cycles of the marine creatures. For example, significant concentrations of chlorine-containing pesticides, toxic dioxins and mercury were found in the tissues of dead dolphins. For all such substances a toxicity threshold is set, and if it is exceeded, it is necessary to remove these substances from production, improve wastewater treatment or legally prohibit their use.
Some good news too! According to the EU EMBLAS project, the processes of restoration of the sea vegetation and animal species – indicators of good environmental conditions – have begun. For example, the red agar-bearing algae Phyllophora can be seen developing and in the coastal zones one could once again find crabs, shrimps and seahorses.
For more interesting facts about the Black Sea take a look at the book "Secrets of the Black Sea".
2. Is there still fish in the Black Sea?
There are more than 200 species of fish in the Black Sea, 30 of them are valuable commercially, such as anchovy, sprat, clupeonella, herring and goby. The largest Black Sea fish is beluga, one of the seven representatives of the sturgeon family in the Black Sea.
However, some of the fish species become rare and are endangered. For example, the seahorse became almost extinct. Tens of thousands of fish were dried annually as souvenirs for tourists. After the seahorse was included in the Red Book of Ukraine and its fishing was banned, its numbers began to grow.
Due to the fact that sturgeon's meat and its black caviar are considered valuable delicacies, excessive fishing decreased the sturgeon population. All seven of the sturgeon species in the Black Sea are under threat of extinction. They are now included in the Red Books of all the Black Sea countries, and their fishing is illegal.
Every year a large amount of fish is caught, and half of the total catch comes from Turkey. Anchovy, mullet, so-iuy mullet and predatory mollusk rapana constitute the bulk of fishing in the Black Sea. As a result of excessive fishing, tuna and mackerel have already disappeared from the Black Sea, and sturgeons are on the verge of extinction. Sturgeon fishing is prohibited in all the Black Sea countries, but poachers constantly violate this ban. The stocks of kalkan and katran flounder are rapidly decreasing; they are also included in the Red Books of the Black Sea countries. During the EMBLAS project surveys, the DNA of the European sturgeon and beluga was found in many samples throughout the Black Sea - this means that some of these unique fish are still swimming in the Black Sea.
The Black Sea is also home to the longnose spurdog, rays, dolphins and 30 species of jellyfish. Large specimens include the widespread moon jellyfish (Aurelia) and Rhizostomae. Aurelia occasionally causes mild burns that go away within an hour, and a larger Rhizostomae can cause painful but not life-threatening skin lesions that disappear in a few days.
Almost 5600 species of living organisms exist in the Black Sea, which is approximatively two times less than in the neighbouring seas. This is also due to the low salinity and comparatively cold climate.
3. How can global warming affect seas and coastal cities?
One of the dangerous consequences of global warming will be a rise in sea level: first, glaciers melt by adding additional volumes of water to the Global Ocean, and, secondly, water expands when heated. Odessa and other Black Sea cities may well share the fate of the flooded Olvia. This may not happen in a year or even in a hundred, but in several centuries.
The Black Sea has its own cycles of water level fluctuations. For example, since the late 1990s, the level of the Black Sea has dropped by an average of 1 cm. This may be due to global climate change - the warmer the sea is, the more water evaporates from its surface. In addition, the warmer and drier the year is, the less water reaches the sea from the rivers flowing into it. The river flows into the Black Sea is much less than 100 years ago. This is because most of the water volume of the Dnieper, Bug, Dniester and Danube is channelled to field irrigation for agriculture purposes. As the temperature rises, in land water consumption increases, while its runoff from the upstream decreases. Heating water in shallow coastal areas can reduce the solubility of oxygen in water. Whole spots of "dead water" (anoxic zones) are formed, where the oxygen saturation is too low for the survival of fish, crabs and shellfish, and they die in big numbers.
With a decrease in river flow into the Black Sea and an increase in ocean levels, salinity in the Black Sea may increase, which means that the Black Sea will become more attractive for settlement by inhabitants from the Mediterranean. Each year, more Mediterranean species such as barracuda and sea turtles swim occasionally into the Black Sea.
4. Is it true that there is a lot of litter in the sea?
With the increase in the use of plastic over the past 20 years, the amount of litter in the oceans has increased hundreds of times - about 8 million tons of plastic find its way into the ocean every year. Circular currents concentrate it in certain places, creating "garbage islands".
The Black Sea is littered twice as much as the Mediterranean and this is due to the transfer of plastic with the runoff of large rivers and the relative isolation of the Black Sea. 85% of all trash in the Black Sea is plastic. Light plastic bottles and bags, floating on the surface of the water, under the influence of ultraviolet rays and temperature gradually disintegrates into smaller fragments, which eventually settle at the bottom of the sea.
Garbage is a problem for marine ecosystems. Firstly, sea creatures often perceive it as food, swallow it, and it clogs their digestive system. The seagulls suffer extensively from this. Secondly, plastic often absorbs organic pollutants, which enter the marine creatures' organisms and poisons them. Thirdly, animals can get trapped, lost and even die in the trash.
It is particularly important to know that in addition to large marine debris there is also microscopic litter called microplastic.. Almost two-thirds of microplastic are formed as a result of tire wear and subsequently washed off the roads. About one-fourth of microplastic comes from the sewers as a result of washing synthetic fabrics, from which microfibers are peeling off. Small plastic granules are often added to household chemicals, as well as to creams, scrubs and toothpastes, which also then go down the drain. The EU EMBLAS project scientists have recorded significant deposits of micro plastic at the bottom of the Black Sea.
Marine life is also affected by the noise pollution: the sounds of container ships, tankers and trawlers. In the areas of intensive navigation, there is an incessant underwater hum, similar to one heard on highways.
The most dangerous are the so-called impulse sounds. When a short signal of huge strength is emitted, it is deafening and leads to concussion. For example, air cannons used in underwater seismic exploration for minerals can produce pulses that are louder than the sound of a space rocket. Therefore, acoustic trauma to the inner ear received by cetaceans during military exercises or seismic surveys could be one of the reasons for them becoming grounded. They lose their ability to navigate using echolocation and distinguishing between the land and the sea.
5. How can the Black Sea be protected?
The European Union is funding several important initiatives that help preserve the Black Sea ecosystem.
Black Sea
"Improving Environmental Monitoring in the Black Sea" (EU EMBLAS) project, implemented by UNDP. The overall goal of the project is to improve the protection of the Black Sea environment in Georgia, Russian Federation and Ukraine. The project studies and surveys the sea, evaluates its "health", and together with environmental activists fights marine litter, especially plastic waste. Cleaning beaches, and recycling marine debris into paving tiles are only few of the multitude of environmental actions organised by the project..
The European Union Water Initiative


Mind 7 min read
Levels Of Consciousness Psychology – How To Rise To The Top?
by Mindvalley November 24, 2018
What is consciousness?
While there are plenty of theories trying to make sense of this elusive thing we call "consciousness," humanity is yet to fully understand what exactly it is.
This post is all about exploring just that. We will dive into consciousness psychology, existence, and how we can use our understanding of consciousness to become the best version of ourselves.
What Is Consciousness Psychology?
What are the different levels of consciousness in psychology?
Although we are yet to ascertain the full breadth and nature of consciousness, we have a fair amount of knowledge about it in terms of the psychological definition of consciousness.
Basically, consciousness psychology refers to the faculty of being aware of our internal and external environments. Everything that we feel, think, sense and do is due to our awareness and consciousness.
This is as simply as you can put it.
There are so many schools of thought about the nature and formation of consciousness that one can only stand in awe.
However, we will stick to our purpose and point you towards the specific aspects of consciousness psychology that we need in order to live our lives in a continuously better manner.
What Is A State Of Consciousness In Psychology?
"States of consciousness" in psychology refers to the condition of consciousness at any given moment. For example, a state of heightened awareness, a state of anxiety or sadness, a sleep state, or a drug-induced state.
Basically, there is a broad spectrum of states that your consciousness can be in, and it all depends on the level of consciousness you are currently living in your life.
What Is An Altered State Of Consciousness In Psychology?
Now, an altered state of consciousness is such a state that you can't achieve normally — such as hypnotic states, lucid dreaming, out of body experiences and many others.
Achieving altered states can help us on the path to self-discovery and realizations, and they can be accessed through different tools and methods with the help of teachers.
However, rarely, some individuals can accidentally find themselves in such states under the effects of drugs, trauma, psychosis, and sleep deprivation. But this may cause harm or psychological impairment.
So, how can we use our understanding of consciousness to become a better human being on this planet?
Let's start by looking at the different levels of consciousness.
What Are The Different Levels Of Consciousness?
What is altered state of consciousness in psychology?
We all know the three levels of consciousness that Freudian psychology has taught us — the conscious, subconscious and unconscious.
But the psychological study of consciousness has moved forward a lot and many advanced viewpoints have emerged. Among them, what is most useful to us is the theory of continuously evolving consciousness.
As per this theory, human consciousness is on an evolutionary journey through subsequent levels of development.
Through this evolutionary process, we have evolved from "early caveman consciousness" to "modern-man" consciousness. Many ancient eastern philosophies also point towards this same truth.
Now, naturally, the question arises: so, what are the next levels of human consciousness?
According to Vishen Lakhiani, the founder of Mindvalley and the author of The Code of the Extraordinary Mind, there are 3 more levels the human consciousness must evolve through to reach full enlightenment.
The levels of consciousness are:
Level 0: Early Man. The humble beginnings of human consciousness when we were hunter-gatherers.
Level 1: Modern Man. Most of humanity is currently living in this level; struggling with both the physical world and the cognitive world of ideas.
Level 2: The Culture Hacker. More and more of us are starting to question the world around them. And that's how we are stepping into the level of the "culture hacker."
Level 3: The State Of Limitless. Sense of mission, connectedness, intuition, inspiration and blessedness are the traits of this state.
Level 4: The God Mind. This is the pinnacle of conscious growth. Only a handful few have experienced it so far.
Read this blog here to learn more about the levels and how to keep evolving consciously.
Why Care About Your Level Of Consciousness?
Simply put, if you care about your personal growth and the growth of humanity, as a whole, you should care about your consciousness and its development.
You should be aware of the level of consciousness you are currently in and actively step up your conscious evolution to reach more enlightened levels.
The truth of existence is, you are here to evolve into higher states of being.
And to make it easier for you, Vishen Lakhiani has created a powerful personal transformation program "Becoming Limitless" using practical tools of consciousness engineering and his real-life knowledge and expertise.
But What If You Didn't Need To Suffer To Be Successful?
Wouldn't That Be Far More Sustainable?
You'll also learn,
Which level of consciousness do you think you are currently in, and how would you like your consciousness to evolve? Share with us in a comment below!
by Mindvalley
Related Articles


text:
Case study: Maintenance of vessels in an effluent treatment plant
This case study was conducted to demonstrate the complex nature of fleet maintenance planning.
The system considered in this study is part of an effluent treatment plant in an oil refinery. This refinery is one of the largest and most complex refineries in the Europe, processing over 250,000 barrels of crude oil per day. The refinery is situated on the sea because of two main reasons. Firstly, this location facilitates the transportation of crude oil to the on-site marine terminal. Secondly, the refinery operations necessitate drawing a large amount of sea water, mostly for cooling purpose. The processed water needs to be purified before it is returned to the sea.
The aim of this support system is to ensure that the purity of the filtered water meets environmental standards set by the government. This means that if this system does not operate at a required capacity, it will directly disrupt other refinery processes. Since the system is used to filter water from multiple refinery systems, different numbers of asset breakdowns lead to different economic consequences for the plant. This is because the operations of different systems will be shut down.
As shown in the figure above, the effluent treatment system consists of seven vessels. Although each vessel can work independently, five of them are required to operate together to satisfy the total demand of the plant. Moreover, the filter process necessitates that a vessel be carried out through a cleaning process at a fixed time period. In other words, the system can operate at full throughput with one vessel out of service (failure or maintenance).
The oil refinery was facing a major problem as the internal lining of the vessel corrodes over time and deteriorates to the point that it cannot protect the vessel wall. Nonetheless, the lining deterioration cannot be detected from the outside. An internal inspection requires a vessel to be uninstalled and incurs high downtime and labour cost. Currently, there are two available maintenance options: patch repair and vessel replacement. As with an internal inspection, both maintenance activities also induce high cost and downtime. A patch repair can take place only once throughout the lifetime of a vessel due to the internal structure of a vessel. The current policy is run-to-failure, which leads to a high risk of production loss, especially when a vessel is uninstalled for maintenance while the others are in poor conditions.
We formulated a mathematical model that captures and explicitly demonstrates dynamic risk of production loss according to the aggregate output of multiple assets. Further, we developed an integrated solution method that couples a finite loop search with a Genetic Algorithm to devise an effective maintenance plan.
Our model outperformed the current run-to-failure (RTF) strategy and binary multi-component k-out-of-N (BMC) approaches in the literature. It results in a 25% reduction in the total cost over the lifetime of the system. A further investigation shows that RTF incurs the lowest maintenance cost but leaves the system highly vulnerable, whereas BMC is the least risky strategy but leads to an overprotective strategy.
- Sanyapong Petchrompo
- Hao Li
- Petchrompo, S., Parlikad, A.K., "Heuristic optimisation for multi-asset intervention planning in a petrochemical plant," In Proc. 7th International Conference on Through-Life Engineering Services, Cranfield, 7 pages, Nov 2018.


text:
August 1980 | NTIA Technical Report TR-80-45
H. T. Dougherty
Abstract: The radio wave propagation path between an earth station and a synchronous satellite 1s described by engineering-type formulas which consolidate all of the known external elements significant for system performance. This UHF/SHF consolidated model, adaptable for subsequent updating, includes state-of-the-art estimates of noise, attenuation, depolarization, and turbulence. The role of system geometry in signal depolarization is presented and the basis for the evaluation of linear versus circular polarization is developed. The conventional figures of merit are included; the determination of service fields (desired signal levels) and potential interference fields (undesired signal levels) are described. The application of the formulas and graphs given in the text are illustrated by numerical examples; their associated derivations are either referenced or covered in the appendices.
Disclaimer: Certain commercial equipment, components, and software may be identified in this report to specify adequately the technical aspects of the reported results. In no case does such identification imply recommendation or endorsement by the National Telecommunications and Information Administration, nor does it imply that the equipment or software identified is necessarily the best available for the particular application or uses.


1. Forum
 2. >
 3. Topic: Klingon
 4. >
 5. Klingon - Is there an easy wa…
Klingon - Is there an easy way to log typos so they can be fixed?
I just started learning Klingon. I am so very happy and grateful to all that worked on this project. Thank you so much.
It is very unfortunate that there is no audio to help with pronunciation. But I understand that may come later if the course proves popular enough.
What is driving me crazy are all the little errors. Mostly in capitalization of words. In the "Tips and notes" section of the very first lesson, "Useful phrases", it is carefully pointed out that capitalization matters.
Note that case matters: some letters are always lowercase (even at the beginning of a sentence!), the others are always uppercase.
Yet right at the very top, under the Lesson heading, where the words to be covered in the lesson are listed, the words have all been made completely in lower case. So, the word "nuqneH" is incorrectly written as "nugneh". There are too many to list here.
See the screenshot. I was sure this was an oversight or a glitch, but it has continued with every lesson I have done so far so far (not many, yet).
I tried to find a place where these typos could be easily logged. It doesn't seem appropriate to put them in a "Bug Report" or under "Troubleshooting". They don't appear to be actual programming errors. (Although I guess they could be.) Plus I do not want to make tens of bug reports just for typos. I just want to be able to list the typos, where I found them, and yes, a screen shot is useful too.
Is there such a place, person, email for this? Can someone please direct me there?
Thanks, Junia_D
"Basic phrases - words"
March 30, 2018
"Programming errors" is probably the best description.
In a number of places, Duolingo forces a given capitalisation on things (e.g. mandatory lowercase as in the lesson preview, mandatory uppercase on the first letter of words in multiple-choice exercises as well as on the first letter of replacement words in distractor sentences if they replace a capitalised word in a real sentence) that are not appropriate for Klingon.
That Duo's treatment of case in Klingon is problematic is already a known problem and developers have it on their list of issues. I don't know when these various problems will be fixed.
So for now: please don't report (systematic) issues with capitalisation, nor about missing sound or missing hints on words that start with apostrophes.
If those things bother you, I recommend that you wait until they get fixed -- I don't know when that will be, though.
Otherwise, please bear with these problems patiently and try to learn anyway :)
Thanks for letting me know that these issues are already known about. I had seen discussions about single-quotes and the forced capitalization of the first words in a sentence, but hadn't seen a mention about the lesson preview words.
I will look forward to seeing fixes come. It easier to live with these knowing that people are working on it and eventually they will be fixed.
I will definitely keep up on learning Klingon.
Thanks again for your response.
Thank you so much for the course. I am enjoying it prodigiously. I was wondering if it will ever be available through the phone app?
Probably when we graduate from beta.
Yeah, I notice that now.
Learn Klingon in just 5 minutes a day. For free.


Relationship of pleural fluid pH and glucose: a multi-centre study of 2,971 cases
Deirdre B. Fitzgerald, Su Lyn Leong, Charley A. Budgeon, Kevin Murray, Andrew Rosenstengal, Nicola A. Smith, Silvia Bielsa, Amelia O. Clive, Nick A. Maskell, Jose M. Porcel, Y. C. Gary Lee
Research output: Contribution to journalArticle
5 Citations (Scopus)
Background: Pleural fluid pH and glucose levels are both recommended in the workup of pleural effusions. Whether their levels correlate and predict each other or contribute independent knowledge is unclear. We aimed to investigate the pH/glucose relationship, assess their concordance and ascertain whether performing both tests provides additional information to performing either test alone.
Methods: The pH and glucose measurements from 2,971 pleural fluid samples, from three centers in Spain, UK and Australia, were categorized into Cancer (n=1,045), Infection (n=544), Tuberculosis (n=249) and Others (n=1,133) groups. The relationship between pH and glucose values and their concordance at clinically relevant cutoffs (pH 7.2 and glucose 3.3 mmol/L) were assessed.
Results: The mean pH of the cohort was 7.38 (SD 0.22) and median glucose 5.99 (range, 0.00-29.36) mmol/L. A regression model of the relationship between glucose (log-transformed) and pH with a restricted cubic spline showed linear (P
Conclusions: Pleural fluid pH and glucose have a strong non-linear relationship but, in most situations, the level of one cannot accurately predict the other. Concordance rates were high and either test is sufficient in the majority of cases.
Original languageEnglish
Pages (from-to)123-130
Number of pages8
JournalJournal of Thoracic Disease
Issue number1
Publication statusPublished - Jan 2019
Cite this


text:
Third grade social studies is exciting! We will start the year learning about our nation's Constitution and government. Our next unit covers map and globe skills and landforms. Most of the year is spent learning about the five regions of the United States. Then we will learn about our country's neighbors, Canada, Mexico, and the Caribbean. We end the year with a unit on economics.
We have a social studies textbook, but we will only use it for the first part of the year. The rest of the year, we will be making a notebook with information about the five regions, Canada, Mexico, and the Caribbean.
Social Studies grades will be based on weekly assessments, tests, projects, participation, and class work. During our study of each region, students will be expected to label the 11 or 12 states of that region on a map as part of their test grade. Although we prepare for this test in class, your Rocket will probably need to spend some time at home practicing recognizing the shapes and locations of the states in the current region. Your child will have a study guide to help practice.


How to Find the Best Studio Monitor Placement
Optimize your listening environment with proper studio monitor placement. This guide will help you find the best spot for your monitors and listening position.
Focal studio monitors and mixing desk
Photo by Focal
Why is Studio Monitor Placement Important?
Building an optimal listening environment is crucial. Proper studio monitor placement is essential for creating mixes that translate on different speaker systems. It also ensures you're hearing your music accurately. Conversely, incorrect studio monitor placement will cause problems in the frequency response of your room. A poor listening environment will also affect how you hear your music which leads to bad mix decisions.
This guide outlines five best practices to follow when setting up your studio monitors. However, these best practices may not work in every studio. But, these tips should provide a good starting point for setting up your listening environment.
1. Finding a Room's Sweet Spot
The first step is to pick the best position for your workstation and studio monitors. Here are some general guidelines:
Place Your Monitors Away from the Walls
Sound waves that bounce off walls and other surfaces can either cancel each other out or multiply. Phase cancellation and frequency buildup are serious problems! Place your monitors eight or more inches away from walls to reduce sound wave reflection issues.
Center Your Monitors and Listening Position
Center your monitors and listening position between the sidewalls to achieve a balanced stereo image. This position ensures equal frequency reflections. A listening position too far left or right will create a buildup of frequencies on that side. While the area further away will have a dip in the frequency response. These two issues will give you an unbalanced representation of your mix.
Also, if your room is small and narrow, try centering the monitors along the widest wall. This position reduces side wall reflections.
Avoid Sitting in the Exact Center of the Room
Placing your monitors and listening position in the center of the room creates various problems. For example, some frequencies that bounce to the center simultaneously can cancel each other out. It also creates a null that causes a dip in the bass response.
Keep Your Listening Position Away from Corners
Avoid placing your studio desk in a corner. Keeping your monitors away from corners will help prevent bass buildup. Low frequencies build up where two reflective surfaces meet. This problem affects how you perceive the low end of your mix.
Positioning Monitors in Large Rectangular Rooms
Consider positioning the monitors along the shorter wall if you have a large rectangular room. The further away your listening position is from the back wall, the better. This position allows sound waves that reflect off the rear wall time to dissipate before reaching you. However, place your monitors on the widest wall if your room is small and the shorter wall is narrow to reduce side wall reflections.
The 38 Percent Rule
Try the 38% rule. For example, if your room is 10 feet long, position your monitors 3.8 feet from the front wall. This distance is a good starting point when finding the sweet spot.
2. The Equilateral Triangle Position
Position your studio monitors to form an equilateral triangle with your listening position. This studio monitor placement will put you in the sweet spot and give you an accurate stereo image.
For example, your listening position should be five feet from the monitors if your monitors are five feet apart. Keeping an equal distance between your monitors and your head is the ideal position.
Also, aim the monitors toward your ears at a 60-degree angle for best results. This position ensures you hear high frequencies accurately.
3. Position Your Studio Monitors at Ear Level
Position the monitor tweeters at ear level. High-frequency content is more directional than low-frequency content. So, directing the tweeters at your ears will allow you to hear higher frequencies more accurately. You can also tilt monitors down to direct the tweeters towards your ears if they are too high.
4. Keep Your Studio Monitors Upright
For best sound reproduction, position the monitors vertically. Don't turn your monitors on their side unless the design allows it. Keeping monitors upright will also place you in the sweet spot and give you accurate sound reproduction.
Moreover, read the manual for your monitors. Some monitors can lay horizontal or vertical. Also, if you place your monitors on their side, position the tweeters toward the outside for best results.
5. Invest in Studio Monitor Stands
Placing monitors directly on your studio desk can cause several problems. For example, sound waves that reflect off your desk will not give you a clear and balanced stereo image. Monitors also transmit their vibrations to any surface they are resting on which could produce unwanted noise. Setting monitors on a desk may also place them below ear level, which is not ideal.
Studio monitor stands are an essential piece of studio equipment worth considering. There are a variety of studio monitor stands. Choose the type that best fits your needs. The three main types are:
Floor stands decouple your monitors from the surface. They allow you to place monitors behind your workstation on secure stands. They also isolate your monitors which prevents surface reflections and vibration.
Desk stands raise the monitors closer to ear level. They also help prevent reflections from interfering with your listening environment. Many are also cushioned to reduce surface vibration.
Isolation pads are foam or rubber stands that lift your monitors off the desk. They provide a cushion to reduce surface vibrations and reflections. Isolation pads are also the most cost-effective studio stand.
Calibrate Your Listening Environment
There is room correction software that measures and calibrates the frequency response of your monitoring. For example, Sonar Reference 4 uses a microphone to measure the frequency response of your room. It then creates an EQ curve that corrects any tonal imbalances. Monitoring through this custom curve will help you hear a more accurate representation of your mix. This method leads to better mixing decisions. It also makes it easier to achieve quality mixes that translate on different speakers.
Knowing the frequency response of your studio will also help you calibrate your monitors. Most studio monitors provide a set of controls on the back to adjust optimal settings.
There are exceptions to every rule. Use your ears to decide what the best studio monitor placement is for your room. Also, consider treating your studio with acoustic treatment. A combination of absorbers, diffusers, and bass traps will create an optimal listening environment.
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text:
Chris Lambright has written one of the only other books (besides mine and one by Greg Valdez) that deals with aspects of the Paul Bennewitz saga, which deal with issues of UFO researchers and what the military will do to misdirect attention. For this second round with Chris, we went a little more into depth about this period in history, discussing what the mysterious objects that Bennewitz photographed might have been, and what the Air Force and others at Kirtland Air Force Base might have been testing. We also delved into the weird orange balls of light that multiple witnesses observed in the Bennewitz home, and the possible technology behind them.
We also went more into depth on the story of John Lear and his sudden appearance on the UFO scene in the mid 1980s, and his immediate impact on research. Chris pointed out his history with the CIA and their covert operations under cover of "Air America" during the Vietnam era in Laos and other countries.
Finally, we talked about his longstanding and detailed research into the famous Socorro incident as well as how some of these threads that reach back to the 1980s and '90s can be found in the present activities of To The Stars Academy and those associated with it.


text:
Lavatube Base Construction. Space 2000: Proceedings of Space 2000: The Seventh International Conference and Exposition of Engineering, Construction, Operations, and Business in Space, Reston VA, USA, p. 631—637.
Blacic J D (1985). Mechanical Properties of Lunar Materials Under Anhydrous, Hard Vacuum Conditions: Applications of Lunar Glass Structural Components. Lunar Bases and Space Activities of the 21st Century, Houston TX, pp. 487-495.
Burke J D (1986). Apollo 15 Lunar Base Site: Steep Slopes as an Energy Resource. Workshop on the Geology and Petrology of the Apollo 15 Landing Site, Spudis P D and Ryder G, eds., Lunar and Planetary Institute, Houston, TX, pp. pp. 38-43.
Carrier W D, III, Olhoeft G R, and Mendell W (1991). Physical Properties of the Lunar Surface. Lunar Sourcebook: A User's Guide to the Moon, Heiken G H, Vaniman D T, and French B M, eds., Cambridge University Press, Cambridge, U.K., pp. 475-594.
Coombs C R, and Hawke B R (1988). A Search for Intact Lava Tubes on the Moon: Possible Lunar Base Habitats, University of Hawaii, Honolulu, HI.
Herbert M V (1990). Preliminary Engineering Analysis, Proposed Oregon Moonbase Research Project, Deschutes County, Oregon. Site Characterization and Phase One Development Plan for the Oregon Moonbase, York (Singer) C L, Walden B, and Billings T L, eds., The Oregon L-5 Society, Inc. (Oregon Moonbase) under NASA NASW-4460, Oregon City, OR, p. 31 pp. + 5 figures & Appendix (2 pp.).
Hörz F (1985). Lava Tubes: Potential Shelters for Habitats. Lunar Bases and Space Activities of the 21st Century, Houston, TX, pp. 405-412.
Kent S R (1990). Efficient Early Lunar Excavation Machine. Engineering, Construction, and Operations in Space II: Proceedings of Space 90, New York, pp. 335-338.
Khalili E N (1985). Magma, Ceramic, and Fused Adobe Structures Generated In Situ. Lunar Habitats and Space Activities of the 21st Century, Houston, pp. 399-403.
McKay D S, Heiken G, Basu A, Glanford G, Simon S, Reedy R, French B M, and Papike J (1991). The Lunar Regolith. Lunar Sourcebook: A User's Guide to the Moon, Heiken G H, Vaniman D T, and French B M, eds., Cambridge University Press, Cambridge, U.K., pp. 285-356.
Meek T T, Vaniman D T, Cocks F H, and Wright R A (1985). Microwave Processing of Lunar Materials: Potential Applications. Lunar Bases and Space Activities of the 21st Century, Houston TX, pp. 479-486.
Walden B E, Billings T L, York C L, Gillett S L, and Herbert M V (1998). Utility of Lava Tubes on Other Worlds. Workshop on Using In Situ Resources for Construction of Planetary Outposts, Houston TX, p. 16—17.
York C L, Walden B, Billings T L, and Reeder P D (1992). Lunar Lavatube Sensing. The Oregon L5 Society, Inc. (Oregon Moonbase), Oregon City, OR.


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Let $(X,L)$ be a polarized abelian variety over $k=\overline{k}$, and let $K(L)$ be the kernel of the isogeny $X\to X^\vee$ that sends $x$ to $t_x^*L\otimes L^{-1}$. The theta group $\mathscr{G}(L)$ of $(X,L)$ is a central extension $$0\to k^\times\to\mathscr{G}(L)\to K(L)\to0.$$ Now, $\mathscr{G}(L)$ acts on $H^0(X,L)$, and we get an irreducible representation $$\mathscr{G}(L)\to \mbox{GL}(H^0(X,L)),$$ which can be seen to descend to a projective representation $K(L)\to\mbox{PGL}(h^0(L)-1,k)$. The nice thing about this projective representation is that, if $\varphi:X\to\mathbb{P}^{h^0(L)-1}$ is the map associated to $|L|$, then for all $z\in K(L)$ and $x\in X$, we have that $z\cdot\varphi(x)=\varphi(x+z)$. Using this, it is easily verified that $\mbox{span}\{\varphi(K(L))\}$ is all $\mathbb{P}^{h^0(L)-1}$.
We have that $K(L)=K_1\oplus K_2$, where $K_2$ is the symplectic complement to $K_1$ using the Weil pairing.
My question is the following: Is it true that the projective representation restricted to $K_1$ (or $K_2$) is also irreducible? Put into other terms, is the linear span of $\varphi(K_1)$ all of $\mathbb{P}^{h^0(L)-1}$?
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I think the answer is no due to the following counterexample (there might be a mistake somewhere though):
Take an elliptic curve $X$ with $L = O_X(3P_0)$ (characteristic $\neq 2, 3$), then $K$ will be the $3$-torsion subgroup and $K_1$ will be generated by a $3$-torsion point $P$. Then in the embedding by $|L|$ of $X$ in $\mathbb{P}^2$, the points $P$, $-P$ and $P_0$ are collinear, that is, $K_1$ is mapped to a lower-dimensional linear subspace.
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Yes, you're right. Great example. Thanks! – rfauffar Feb 8 '13 at 4:09
If I understand correctly, $K_1$ and $K_2$ are (mutually orthogonal maximal) isotropic subgroups of $K(L)$. Therefore they both can be lifted (non-canonically) to (finite) commutative (sic!) subgroups of the theta group. In particular, the restriction of the projective representation of $K(L)$ to $K_i$ is actually a projectivization of a certain linear representation of finite commutative $K_i$ in $H^0(X,L)$. Since a linear representation of such groups is irreducible if and only if it is one-dimensional, we get a negative answer to your question (unless $H^0(X,L)$ has dimension 1, i.e. $L$ defines a principal polarization).
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Now, I'm not asking necessarily when the linear representation of $K_i$ es irreducible (since by what you said, $L$ would have to be a principal polarization), but when the projective representation is irreducible; i.e., the group doesn't fix any projective linear space of $\mathbb{P}H^0(L)$... – rfauffar Feb 10 '13 at 4:04
The answer is the same: iff the polarization is principal. If it is not principal then one may take the projectivization $P(W)$ of any proper nonzero $K_i$-invariant vector subspace $W$ of $H^0(X,L)$; this $P(W)$ is $K_i$-stable. – Yuri Zarhin Feb 15 '13 at 17:07
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|Rediff India Abroad Home | All the sections|
What is 3G spectrum? How does it help you?
rediff Business Desk | September 29, 2006
It's boom time for mobile phones in India. And people are looking forward to more information, faster data access and multimedia services through their mobile phones. 3G technology is here to turn this dream into reality. It's a technology anxiously awaited by telecom operations and subscribers in India.
How long do you have to wait?
Not very long! India is all set to launch 3G mobile telephone services by June 2007.
According to Telecom Regulatory Authority of India chairman Nripendra Misra, a total of 32.5 MHz is available for allocation within the next 6-9 months.
Trai has also recommended auctioning 200 MHz for broadband wireless access services like Wimax (worldwide interoperability for microwave access) and has proposed a national frequency management board to oversee spectrum availability and its efficient use.
He hopes that the allocated spectrum would be enough for the next two years and said Trai would recommend freeing up more spectrum for those who lose out in this auction.
So what is 3G spectrum all about? Read on.
What is spectrum?
Radio spectrum refers to a range of radio frequencies. The bandwidth of a radio signal is the difference between the upper and lower frequencies of the signal.
For example, in the case of a voice signal having a minimum frequency of 200 hertz (Hz) and a maximum frequency of 3,000 Hz, the bandwidth is 2,800 Hz (3 KHz). The amount of bandwidth needed for 3G services could be as much as 15-20 Mhz, whereas for 2G services a bandwidth of 30-200 KHz is used. Hence, for 3G huge bandwidth is required.
How is 3G different from 2G and 4G?
While 2G stands for second-generation wireless telephone technology, 1G networks used are analog, 2G networks are digital and 3G (third-generation) technology is used to enhance mobile phone standards.
3G helps to simultaneously transfer both voice data (a telephone call) and non-voice data (such as downloading information, exchanging e-mail, and instant messaging. The highlight of 3G is video telephony. 4G technology stands to be the future standard of wireless devices.
Currently, Japanese company NTT DoCoMo and Samsung are testing 4G communication.
How will 3G services help you?
3G services will enable video broadcast and data-intensive services such as stock transactions, e-learning and telemedicine through wireless communications
All telecom operators are waiting to launch 3G in India to cash in on revenues by providing high-end services to customers, which are voice data and video enabled. India lags behind many Asian countries in introducing 3G services.
What is Trai's recommendation on 3G pricing?
The Telecom Regulatory Authority of India has recommended auctioning radio frequencies for 3G telecom services at a reserve price of Rs 1,050 crore (Rs 10.50 billion) to companies seeking to offer nationwide high-speed Internet and streaming video.
The base price for spectrum in cities like Mumbai and Delhi and Category A telecom circles is Rs 80 crore (Rs 800 million); in cities like Chennai and Kolkata and Category B circles Rs 40 crore (Rs 400 million); and in all other cities Rs 15 crore (Rs 150 million).
What are the frequency bands and quota for CDMA?
Trai has recommended three sets of frequency bands - 450 mhz, 800 mhz and 2.1 ghz. For CDMA players like Reliance and Tata Teleservices 1.25 MHz each is offered. CDMA operators are free to bid both in the 2.1 GHz and the 450 MHz bands, but they will be allocated spectrum only in one. The pricing of these two bands is linked to the auction in the 2.1 GHz band.
CDMA operators will pay the same as the second-highest GSM bidder. And if there is more than one claimant in the 450 MHz band, the reserve price will be half of that arrived at in the 2.1 GHz band. Another rider is that if the highest bid is a quarter more than the lowest, the lowest bidder has to raise its bid to 75 per cent of the winning bid.
But CDMA operators are likely to face problems. Operating 3G services on 450 MHz is a problem because we they do not have dual-band phones that work both in 450 MHz and in 800 MHz (the band in which CDMA operates in India).
What are the issues regarding 3G for providers and users?
3G has successfully been introduced in Europe. But several issues continue to hamper its growth.
High spectrum licensing fees for the 3G services
Huge capital required to build infrastructure for 3G services.
Health impact of electromagnetic waves.
Prices are very high for 3G mobile services.
Will 2G users switch to 3G services.
Takes time to catch up as the service is new.
What are the issues regarding 3G pricing?
Pricing has been a cause of concern. Spectrum auctions ran into billions of euros in Europe. In Europe, spectrum licensing fees were collected years before the 3G service was developed and it required huge investments to build 3G networks, hitting mobile operators' margins.
However, in Japan and South Korea, spectrum licensing fees were not applicable as the focus of these countries were national IT infrastructure development.
Which companies have applied for 3G license?
3G spectrum has been provided to GSM players like BSNL, MTNL, Bharti, and Hutch to carry out an interface check on a non-commercial basis ahead of the start of 3G mobile services.
Trial spectrum has been given for a period of one month. This will be only 1/1000th of the actual 3G spectrum capability. Apart frm PSU majors, spectrum for carrying out 3G trials has been given to all those who have applied under the National Frequency Allocation Plan on the 2.1 GHz band. GSM players operate on 900 MHz and 1,800 MHz, while CDMA players operate on 800 MHz.
What is the pricing issue in India?
While Tatas have welcomed Trai's Rs 1,400-crore (Rs 14 billion) base price for a nationwide rollout of 3G services, the rest of the players find the price too exorbitant.
Bharti-Airtel is disappointed with the pricing as they were expecting it to be Rs 300-400 crore (Rs 3-4 billion). The reserve price is a disincentive for telecom companies in India. Bharti has appealed to lower the prices specially for rural penetration.
The Cellular Operators Association of India and the Association of Unified Service Providers of India are studying TRAI's recommendations and have not given their comments.
However, Trai chairman Nripendra Misra has said that there is no reason to worry as players will not bid exorbitantly and derail the auction. Misra said telecom operators had matured from their experiences and global developments, and would bid sincerely.
Where was 3G spectrum first introduced?
Japan was the first country to introduce 3G on a large commercial scale. In 2005, about 40 per cent of subscribers used only 3G networks. It is expected that during 2006 the subscribers would move from 2G to 3G and upgrade to the next 3.5 G level.
The success of 3G in Japan also shows that video telephony was the killer application for 3G networks. Downloading music was the biggest draw in 3G services.
In how many countries does 3G exist?
There are about 60 3G networks across 25 countries. In Asia, Europe and the USA, telecom firms use WCDMA technology. The WCDMA standard provides seamless global evolution from today's GSM with support of the worlds' largest mobile operators.
WCDMA technology is built on open standards, wide ranging mobile multimedia possibility, and vast potential economies of scale with the support of around 100 terminal designs to operate 3G mobile networks.
3G services were introduced in Europe in 2003.


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INVESTIGATION TIMELINES AND SUMMARY PROCESS
We aim to action and resolve all stages of the investigation within 10 working days of receipt of the allegation.
The fundamental principle of all investigations is to conduct them in a fair, reasonable and legal manner, ensuring that all relevant evidence is considered without bias. In doing so investigations will be based around the following broad objectives:
- To establish the facts relating to allegations/complaints in order to determine whether any irregularities have occurred.
- To identify the cause of the irregularities and those involved.
- To establish the scale of the irregularities.
- To evaluate any action already taken
- To determine whether remedial action is required to reduce the risk to current registered learners and to preserve the integrity of JOIE beauté and the qualification.
- To identify any adverse patterns or trends.
The investigation may involve a request for further information from relevant parties and/or interviews with personnel involved in the investigation. Therefore, we will:
- Ensure all material collected as part of an investigation must be kept secure.
- If an investigation leads to invalidation of certificates, or criminal or civil prosecution, all records and original documentation relating to the case will be retained until the case and any appeals have been heard and for five years thereafter.
- Expect all parties, who are either directly or indirectly involved in the investigation, to fully co-operate with us.
Either at notification of a suspected or actual case of malpractice or maladministration and/or at any time during the investigation, we reserve the right to withhold a learner's, and/or cohort's, results.
Where a member of JOIE beauté's staff or an JOIE beauté Associate is under investigation we may suspend them or move them to other duties until the investigation is complete.
Throughout the investigation our Director will be responsible for overseeing the work of the investigation team to ensure that due process is being followed, appropriate evidence has been gathered and reviewed and for liaising with and keeping informed relevant external parties.


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Roblox is a massively multiplayer online game created and marketed toward children and teenagers. It allows players to create their own virtual worlds and games. Driving in Roblox can be tricky, as the controls are slightly different from those in the real world. The following guide will teach you the basics of how to drive in Roblox.
How To Drive In Brookhaven Roblox
Brookhaven is a small town in Maine. The roads are narrow and there are many curves. Drive slowly and use caution when turning. There are no stoplights, so use caution when crossing intersections.
-A computer with internet access -A Roblox account -A working knowledge of how to use a computer -Some spending money to buy in-game items
- Select a car
- Enter the game
- Drive around the map avoid crashing into other cars or obstacles
– Always drive on the right side of the road. – Yield to pedestrians. – Follow all traffic signs and signals. – Use caution when driving in crowded areas.
Frequently Asked Questions
How Do You Play Brookhaven?
The objective of the game is to explore the town of Brookhaven and solve the mysteries within. The player can explore the town by walking around, and can interact with objects and characters by selecting them. Some objects can be interacted with more than once, and some characters will give the player tasks to complete. The player can also access a menu to check their inventory, map, and objectives.
How Do You Drive A Roblox Car On Ipad?
You can drive a Roblox car on an iPad by using the virtual joystick controls that appear on the screen.
How Do You Drive A Car In Roblox?
To drive a car in Roblox, you need to use the arrow keys on your keyboard.
Brookhaven is a busy town, so take care when driving. There are a lot of pedestrians and cyclists, so be vigilant and always give way. The roads are generally in good condition, but there are some areas that can be tricky to navigate, so take your time and pay attention to signage.


Definition of across preposition from the Oxford Advanced American Dictionary
 jump to other results
 1. 1from one side to the other side of something He walked across the field. I drew a line across the page. A grin spread across her face. Where's the nearest bridge across the river?
 2. 2on the other side of something There's a bank right across the street.
 3. 3 on or over a part of the body He hit him across the face. It's too tight across the back.
 4. 4in every part of a place, group of people, etc. synonym throughout Her family is scattered across the country. This view is common across all sections of the community.
See the Oxford Advanced Learner's Dictionary entry: across


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Flashing and Drainage
Flashing is a crucial component in modern masonry walls. Whereas solid, multi-wythe masonry walls mostly constructed before the 1900s manage water infiltration through absorption and evaporation, modern masonry walls must accommodate moisture penetration by providing a collection and drainage system. This system consists of flashing and weeps. Flashing also serves to prevent water penetration at interfaces with other building systems, such as windows and other penetrations.
Cavity wall design recognizes that water penetration through masonry is inevitable, and it provides the necessary means to manage moisture. Flashing location, material selection, detailing and proper installation are all significantly important to ensure that water does not penetrate to the interior areas of buildings.
|Flashing seams or laps that are not properly sealed can lead to water leakage.
Locating flashing is a fairly straightforward task, provided water flow and the limitations of the building wall components are well understood. Masonry walls are porous, often including paths for water penetration, such as cracks and poorly bonded mortar joints; even if properly installed, window perimeter and coping stone sealant degrades over time. Also, through-wall penetrations at pipes, conduit, vents and air conditioning sleeves obviously breach the skin of a building. Each of these locations provides the opportunity for water penetration.
Once moisture has penetrated through the exterior veneer of the masonry wall, it will begin flowing down the interior face of the veneer. Where the vertical flow of water is interrupted by a horizontal surface, water has the potential to penetrate to the interior areas of a building. Such interruptions typically occur at wall bases, shelf angles, lintels, slab edges, through-wall penetrations and windowsills. These are the primary locations where flashing is necessary to manage water.
Flashing also is used at other locations to prevent moisture penetration, more so than managing water after penetration. This is typically the case at coping stones on parapet walls and at the head and jambs of windows.
It should be noted that most model building codes, including the 2000, 2003 and 2006 versions of the International Building Code (IBC), require installation of flashing at various areas of masonry walls. The specific locations where flashing is required in each version of the IBC have changed slightly over the years; however, the intent remains the same.
|Failure to properly install flashing at wall corners and intersections can lead to water leakage, and possibly mold.
Flashing materials must be resistant to punctures during construction, they must be corrosion resistant, they must not absorb moisture, and they should be fairly easy to install. More importantly, all flashing materials should be able to provide their intended waterproofing function. Flashing material often is selected based on cost and suitability, but service life also should be considered. Failure of the flashing prior to the end of the useful life of a building will require expensive repairs; therefore, only highly durable materials should be used in masonry construction.
The most durable flashing materials are sheet metals typically copper and stainless steel. These materials are resistant to punctures, corrosion and water absorption. However, installation is somewhat more difficult than for flexible materials, since they require shop or field bending prior to installation. Another factor is the sealing of laps and joints, which normally is accomplished by soldering the sheet metal sections together. Sheet metals also tend to be the most expensive flashing materials.
One of the most common materials used for flashing is rubberized asphalt. It typically comes in variable width sheets and is self-adhesive. The sheets are manufactured through careful blending of rubberizing agents with asphalt (typically SBS or SEBS). The rubberized asphalt then is laminated with a backing material, usually high-density polyethylene. These products are usually 40 mils thick, are flexible, easy to install, non-corrosive, and will not absorb water. They are a somewhat less durable than sheet metal since they are more susceptible to punctures. However, since this type of flashing often is fully adhered to the substrate, a puncture will not necessarily result in a leak. Nonetheless, punctures should not be tolerated in any kind of flashing installation. Laps and joints in rubberized asphalt flashing materials are sealed through the self-adhesive properties of the material.
Thin approximately 20 mils thick or less polyethylene sheeting (plastic) also is being used as flashing. However, this is not a durable material. In such thicknesses, polyethylene has nearly no puncture resistance and will degrade over short periods of time. Additionally, sealing joints and laps in thin polyethylene or other types of plastic sheets is difficult.
There are many other types of through-wall flashing products such as laminated copper sheets. Before specifying any flashing materials, they should be evaluated for their durability and installation practicality.
Flashing accessories such as termination bars, drip edges, solder, primers, adhesives and sealants must also be durable and compatible with flashing and other wall materials. Metal components must be non-corrosive and sealants must remain soft and flexible. No material should adversely affect any other material within the wall system.
|End dams are often formed using a combination of flexible flashing with a sheet metal backup to ensure proper geometry of the flashing is maintained during construction.
Although quality mason contractors should fully understand the purpose of flashing and installation requirements, flashing systems should be thoroughly detailed on the construction drawings. These details should provide direction to the contractor in forming end dams and corners, installing termination bars and drip edges, sealing seams, providing expansion joints, and installing proper flashing support.
Detailing flashing to collect and divert water from the interior cavity wall surfaces to the exterior should consider the following:
- End dams must be used at the ends of each length of non-continuous flashing to force water to the exterior of the masonry cavity walls. The most common location for end dams is at the ends of window lintels and windowsills. Without them, water will flow along and off of the end of the lintel into the wall cavity (path of least resistance). However, since the window lintel spans the full width of the wall cavity, water can spill into the cavity at or near the interior walls, exposing them to potential water penetration.
- Proper detailing at corners is necessary to ensure moisture does not penetrate through the flashing system. Details for corners must indicate locations for seams and laps. Corner details may include the use of preformed sheet metal, even if rubberized asphalt flashing is used.
- Flashing must extend through the full thickness of the wall and terminate beyond the face of the wall with a drip edge. Terminating flashing within the exterior wythe of masonry could allow water to travel back beneath the flashing, into the cavity, and possibly back to the interior wythe of the wall system. Use of self-adhesive rubberized asphalt flashing should include separate, stainless steel drip edges adhered directly to lintels and shelf angles, beneath the self-adhesive flashing. This is because rubberized asphalts will degrade with UV exposure. Therefore, when used with a stainless steel drip edge, the rubberized asphalt does not need to extend beyond the face of the exterior wall.
- The interior vertical leg of flashing should extend up a minimum of eight inches. The top edge of the flashing must be terminated properly. The two most common termination methods are embedment in a bed joint of the masonry backup or with a termination bar. Termination bars should be fairly stiff to provide a uniform clamping force between the fasteners and resist bending during installation. A "[" shape often is best for this purpose. Termination bars should also be corrosion resistant.
- Details of seams should include a minimum lap length of four inches. Although metal flashing often is soldered at the seams, sometimes it is better to adhere the lapped areas with flexible sealant. This will accommodate thermal expansion and contraction where soldered seams will not.
- Flexible flashing must be fully supported across the full width of the wall cavity below. At shelf angles and lintels this is always the case. However, flexible flashing placed at floor lines without shelf angles will form a trough over the width of the cavity if supplemental support is not provided. This trough will retain water and can cause large leaks where there are any small imperfections in the flashing seams. Water will then flow through the seams, into the cavity space below and possibly down the face of the interior wythe, exposing interior areas of a building to water penetration. Supplemental support typically is provided through installation of a sheet metal angle attached to the masonry backup wythe and spanning across the full width of the cavity.
- Penetrations through flashing materials, such as at coping stone anchors, must be detailed to ensure the penetration is watertight. Most often, this is accomplished with a flexible sealant or mastic.
- Weeps must be placed in the mortar joint immediately above the flashing at a maximum of 24 inches on center. In general, the larger the weeps, the better. Cell vents installed in head joints, typically the same size as a head joint, will quickly remove more water than cotton rope or small plastic tube weeps.
Flashing details are often best presented in isometric views. In particular, details at corners and end dams are difficult to show clearly in traditional, two-dimensional details.
Although not specifically the topic of this article, it is important to note that flashing cannot serve its intended purpose if the wall cavity is too narrow and not kept clean during construction. For cavity walls to function as intended, they must be designed with a minimum inch-inch wide cavity. This dimension is considered the minimum width necessary, as recommended by the Brick Industry Association, to prevent the cavity from being bridged by mortar or other materials and to allow water to cross over to the interior wythe. Narrower cavities are far more difficult to keep clear during construction. However, it should be noted that mortar brid