10 Objects. These 10 triangle objects have the same properties and behaviors (but the specific side length values are different), you can change them Abstraction is a type, called triangle type. In C++, this type can be defined as "class". This Ten triangles are objects belonging to the same "class". Just as 10 Chinese belong to the "Chinese" category, 10 Americans Belongs to the "American" category. A class is an abstraction of an object, and an object is a special case of a class, or a concrete manifestation of a class form.
Inheritance and Reuse in Object-Oriented Programming:
If a car manufacturer wants to produce a new type of car, it will generally not design it all from scratch.
Based on a certain model of car, some new functions are added to develop a new model of car. This is to improve health Common methods of productivity. If you have already established a "class" named A in software development, and you want to create another named B "Class", while the latter is basically the same as the former, except that some attributes and behaviors are added on the basis of the former. Then design a new class from scratch, and only need to add some new content on the basis of class A. This is the object-oriented process Inheritance mechanism in order design. Using inheritance can simplify the steps of programming. For example: if everyone has Having fully understood the characteristics of horses, now I want to describe the characteristics of "white horses". Obviously, it is not necessary to introduce what a horse is from the beginning, but just say Clearly, "a white horse is a white horse". This simplifies people's The knowledge and description of things simplifies work procedures. "White Horse" inherits the basic characteristics of "horse" and adds new characteristics (color). "Horse" is the parent category, or called the base The class "white horse" is derived from "horse" and is called a subclass or derived class. If you still want to define "white stallion", just say Ming "a white stallion is a male white horse". "White Stallion" is a subtype or derivative of "White Horse".
 C++ provides an inheritance mechanism, and the inheritance method can easily use an existing class to create a new This can reuse part or even most of the existing software, which greatly saves programming workload. This is often The idea of "software reusability" can not only use the classes you have built in the past, but also You can use the classes used by others or the classes stored in the class library, and these classes can be used after proper processing, which greatly shortens The software development cycle is of great significance to the development of large-scale software. 5. Polymorphism If there are several objects that are similar but not exactly the same, sometimes people require that when sending the same message to them, it They reacted differently and performed different operations. This situation is polymorphism. For example, A, B, C 3 The classes are all in the second grade. They have basically the same attributes and behaviors. When they hear the class bell at the same time, they will go separately Enter 3 classrooms without going to the same classroom. Similarly, if there are two armies, when you hear a kind of The sound of the trumpet, due to different prior agreements, the A army may carry out an offensive, while the B army may prepare to start a meal. Another example, in Windows
In the environment, double-click a file object with the mouse (this is to send a message to the object), if the object is An executable file, this program will be executed, if the object is a text file, a text editor will be launched and opened The document. There are many situations. In C++, the so-called polymorphism (polymorphism) refers to: related different classes produced by inheritance, which Objects will respond differently to the same message. Polymorphism is an important feature of object-oriented programming, which can increase the flexibility of the program.
The role of classes and objects in object-oriented programming
"Class" is a very important concept in C++, it is the basis of object-oriented programming. C++ to C The most important thing for improvement is to add a type of "class". So C++ was originally called "C with classes". class It is a common feature of all object-oriented languages, and all object-oriented languages provide this type. If one Computer language does not contain classes, it cannot be called an object-oriented language. A C++ program of a certain scale is Composed of many categories. It can be said that classes are the soul of C++. If you don't really master classes, you can't really control them.
C++ supports process-oriented programming, as well as object-based and object-oriented programming. From this chapter to Chapter 4 introduces object-based programming. Including the concepts of classes and objects, the mechanisms and declarations of classes, and the definition of class objects And use etc. This is the basis of object-oriented programming. due to Object-based is based on class. Unlike process-oriented programs, object-based programs are based on classes and objects
Basically, the operation of the program is carried out around the object. On this basis, using inheritance and polymorphism, it becomes Object programming (sometimes not subdivided based on object programming and object-oriented programming, and the two are collectively referred to as Object-oriented programming). Object-based programming faces each object. All data belong to different objects. Face to The data in the process program is public or shared. If there are variables a, b, c, they can be used by different functions.
Call, which means that these data are lack of protection. The cross-use of data can easily lead to program errors. And real In fact, each set of data in the program is prepared for a certain operation, that is, a set of data is related to a set of operations. For the corresponding. Therefore, people imagine that related data and operations are put together to form a whole, which is relatively separated from the outside world. Separated. This is the object in object-oriented programming. In process-oriented structured programming, people often use this formula to express the program:
Program = Algorithm + Data Structure The algorithm and data structure are independent and designed separately, and the process-oriented programming is based on the algorithm. of. In practice, people gradually realize that algorithms and data structures are closely related to each other and inseparable. The method corresponds to a set of data structures, and it is not advisable to advocate that one algorithm corresponds to multiple sets of data structures, and one set of data structures corresponds to multiple data structures.
Algorithms. Object-based and object-oriented programming is to encapsulate an algorithm and a set of data structures in an object. Therefore, a new concept was formed:
Object = algorithm + data structure Program = (Object+Object+Object+…)+Message Or expressed as Program = Object S+ Message "Object" means "multiple objects". The function of the message is to control the object. The key to programming is design Good for each object, and determine the commands issued to these objects, so that each object completes the corresponding operation.
Example write a program Using public and private in C++ Class
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By examining the mouthparts of a river insect, Australian researchers have shown that rivers can bounce back after years of damaging pollution.
RIVERS HAVE THE ABILITY to bounce back to health from years of pollution, offering hope for rivers worldwide, according to the results of a new Victorian study.
Melbourne University researchers Vincent Pettigrove and Bryant Gagliardi studied the rivers in the Ovens Valley, north east Victoria, which had been polluted with pesticides from 150 years of tobacco farming.
They found that by examining the mouthparts of a common river insect, the non-biting midge, or 'chironomid', they could ascertain whether pesticides — for example DDT, a now-banned carcinogenic toxin — were present in the river. Deformities included missing, additional or fused 'teeth'. The researchers said that insect deformity can be a cheaper measure of river health than traditional chemical analysis and can assist agriculture in managing land more sustainably.
"We have seen that land-managers can make decisions about how they use their land that positively impact aquatic ecosystems because current farming practices in the area are having a lesser impact on the Ovens River," Dr Pettigrove said.
The Oven's River Basin is located in the Murray Darling catchment. Tobacco cultivation occurred from the 1850s and peaked during the 1970s. The use of pesticides such as DDT were banned in Victoria in 1981, and, after years of declining profit margins, the industry completely closed in 2006.
The study examined midge larvae at tobacco sites, in 1988 and again in 2010, as well as sites 10km upstream and downstream, to see changes over time. The 1988 research showed a significantly higher amount of deformities in the larvae collected at the tobacco sites compared with upstream and downstream samples. But in 2010, the amount of deformities was not significantly different between the different locations.
Midge larvae are commonly found in the fine sediments of slow-flowing rivers, which is also where pesticides and heavy metals are likely to accumulate.
In addition to DDT, the sediments were also examined for other pollutants (organochlorides). In 1988, significant levels of DDT were detected at the tobacco zone but the tests were not considered sensitive enough to be reliable.
In 2010, the sediment analysis was much more comprehensive, including screening for numerous different pesticides and heavy metals over a much larger area. DDT and related organochlorides were found only at the tobacco sites.
The authors acknowledged the reduction in the midges' deformities might have indicated an adaptation to the pesticides since 1988, but dismissed this idea as previous studies into the Australian sheep blowfly found that adaptation occurred within a 10 year timeframe. Since pesticides were used in the Ovens valley between the 1950s and 1981, any adaptations would have occurred prior to 1988.
According to the researchers, using the midge as a 'bioindicator' is an inexpensive and reliable method for indicating the presence of pollutants. The results in the Ovens Valley showed that improved farming practices can significantly improve the health of local rivers within a short space of time. The findings could be used to help rivers worldwide.
"The improvement in health of the chiromonid is significant as an indicator of river health as they are found in every type of freshwater environment worldwide and are an important food resource for fish," said Pettigrove.
The findings were published in the journal Agriculture, Ecosystems and Environment.
Sarah Hardgrove wrote this article as part of her science communication studies at the University of Melbourne.

source: openbmb/Ultra-FineWeb


Line Shaft
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Line Shaft
Four wool spinning machines driven by belts from an overhead lineshaft (Leipzig, Germany, circa 1925)
A line shaft is a power-driven rotating shaft for power transmission that was used extensively from the Industrial Revolution until the early 20th century. Prior to the widespread use of electric motors small enough to be connected directly to each piece of machinery, line shafting was used to distribute power from a large central power source to machinery throughout a workshop or an industrial complex. The central power source could be a water wheel, turbine, windmill, animal power or a steam engine. Power was distributed from the shaft to the machinery by a system of belts, pulleys and gears known as millwork.[1]
Variable speed belt drive for a lathe. The fixed pulley on the upper shaft is driven at constant speed by a belt from the power source. The loose pulley ('idler') allows the machine to be stopped in isolation - necessary for changing speed. The stepped pulleys (left) provide three drive speeds for the machine tool (not shown), depending on which pair of pulleys is connected by the belt.
From turbine to line shaft at Suffolk Mills in Lowell, Massachusetts
From line shaft to power looms at Boott Mills in Lowell, Massachusetts
A typical line shaft would be suspended from the ceiling of one area and would run the length of that area. One pulley on the shaft would receive the power from a parent line shaft elsewhere in the building. The other pulleys would supply power to pulleys on each individual machine or to subsequent line shafts. In manufacturing where there were a large number of machines performing the same tasks, the design of the system was fairly regular and repeated. In other applications such as machine and wood shops where there was a variety of machines with different orientations and power requirements, the system would appear erratic and inconsistent with many different shafting directions and pulley sizes. Shafts were usually horizontal and overhead but occasionally were vertical and could be underground. Shafts were usually rigid steel, made up of several parts bolted together at flanges. The shafts were suspended by hangers with bearings at certain intervals of length. The distance depended on the weight of the shaft and the number of pulleys. The shafts had to be kept aligned or the stress would overheat the bearings and could break the shaft. The bearings were usually friction type and had to be kept lubricated. Pulley lubricator employees were required in order to ensure that the bearings did not freeze or malfunction.
In the earliest applications power was transmitted between pulleys using loops of rope on grooved pulleys. This method is extremely rare today, dating mostly from the 18th century. Flat belts on flat pulleys or drums were the most common method during the 19th and early 20th centuries. The belts were generally tanned leather or cotton duck impregnated with rubber. Leather belts were fastened in loops with rawhide or wire lacing, lap joints and glue, or one of several types of steel fasteners. Cotton duck belts usually used metal fasteners or were melted together with heat. The leather belts were run with the hair side against the pulleys for best traction. The belts needed periodic cleaning and conditioning to keep them in good condition. Belts were often twisted 180 degrees per leg and reversed on the receiving pulley to cause the second shaft to rotate in the opposite direction.
Pulleys were constructed of wood, iron, steel or a combination thereof. Varying sizes of pulleys were used in conjunction to change the speed of rotation. For example, a 40" pulley at 100 rpm would turn a 20" pulley at 200 rpm. Pulleys solidly attached ("fast") to the shaft could be combined with adjacent pulleys that turned freely ("loose") on the shaft (idlers). In this configuration the belt could be maneuvered onto the idler to stop power transmission or onto the solid pulley to convey the power. This arrangement was often used near machines to provide a means of shutting the machine off when not in use. Usually at the last belt feeding power to a machine, a pair of stepped pulleys could be used to give a variety of speed settings for the machine.
Occasionally gears were used between shafts to change speed rather than belts and different-sized pulleys, but this seems to have been relatively uncommon.
Early versions of line shafts date back into the 18th century, but they were in widespread use in the late 19th century with industrialization. Line shafts were widely used in manufacturing, woodworking shops, machine shops, saw mills and grist mills.
In 1828 in Lowell, Massachusetts, Paul Moody substituted leather belting for metal gearing to transfer power from the main shaft running from a water wheel. This innovation quickly spread in the U.S.[2]
Flat-belt drive systems became popular in the UK from the 1870s, with the firms of J & E Wood and W & J Galloway & Sons prominent in their introduction. Both of these firms manufactured stationary steam engines and the continuing demand for more power and reliability could be met not merely by improved engine technology but also improved methods of transferring power from the engines to the looms and similar machinery which they were intended to service. The use of flat belts was already common in the US but rare in Britain until this time. The advantages included less noise and less wasted energy in the friction losses inherent in the previously common drive shafts and their associated gearing. Also, maintenance was simpler and cheaper, and it was a more convenient method for the arrangement of power drives such that if one part were to fail then it would not cause loss of power to all sections of a factory or mill. These systems were in turn superseded in popularity by rope drive methods.[3]
Near the end of the 19th century some factories had a mile or more of line shafts in a single building.
In order to provide power for small shops and light industry, specially constructed "power buildings" were constructed. Power buildings used a central steam engine and distributed power through line shafts to all the leased rooms. Power buildings continued to be built in the early days of electrification, still using line shafts but driven by an electric motor.[1]
As some factories grew too large and complex to be powered by a single steam engine, a system of "sub divided" power came into use. This was also important when a wide range of speed control was necessary for a sensitive operation such as wire drawing or hammering iron. Under sub divided power, steam was piped from a central boiler to smaller steam engines located where needed. However, small steam engines were much less efficient than large ones. The Baldwin Locomotive Works 63-acre site changed to sub divided power, then because of the inefficiency converted to group drive with several large steam engines driving the line shafts. Eventually Baldwin converted to electric drive, with a substantial saving in labor and building space.[1]
Printing presses in 1870
With factory electrification in the early 1900s, many line shafts began converting to electric drive. In early factory electrification only large motors were available, so new factories installed a large motor to drive line shafting and millwork. After 1900 smaller industrial motors became available and most new installations used individual electric drives.[4]
Steam turbine powered line shafts were commonly used to drive paper machines for speed control reasons until economical methods for precision electric motor speed control became available in the 1980s; since then many have been replaced with sectional electric drives.[5] Economical variable speed control using electric motors was made possible by silicon controlled rectifiers (SCRs) to produce direct current and variable frequency drives using inverters to change DC back to AC at the frequency required for the desired speed.
Most systems were out of service by the mid-20th century and relatively few remain in the 21st century, even fewer in their original location and configuration.
Disadvantages and alternatives
Compared to individual electric motor or unit drive, line shafts have the following disadvantages:[1]
 - Power loss with line shafts varied widely and was typically 25% and often much higher; however, using roller bearings and good quality lubrication could minimize losses. Roller and spherical bearings gained acceptance in the decade before electrification of factories began.
 - Continuous noise
 - Maintenance costs were higher.
 - The systems were more dangerous.
 - Down time due to mechanical problems was higher.
 - It was not as easy to change speed.
 - Factory layout was designed around access to the line shafts, not in the most efficient manner for the work flow.
 - The line shafts and millwork took up a lot of space; Baldwin Locomotive Works estimated 40% more than electric drive.
 - The shafts and belting were in the way of lighting, overhead cranes and ventilation ducts.
 - Alignment of the system was critical and problematic for long shafts that were subject to expansion and contraction, settling and vibration.
 - The belting shed dust and kept it continuously circulating in the air.
 - Oil dripped from the overhead shafting.
Firms switching to electric power showed significantly less employee sick time, and, using the same equipment, showed significant increases in production. Writing in 1909,[where?] James Hubbart said that "We can scarcely step into a shop or factory of any description without encountering a mass of belts which seem at first to monopolize every nook in the building and leave little or no room for anything else


text: Geo-energy is a resource available widely on Earth that consist in using the first 10-100 meters bellow surface where the temperature is low and constant during the year. This 12 to 15°C is ideal for heat pumps to provide heat and cold with an excellent coefficient of performance. Despite a very high potential, this resource is not often integrated in France. One of the main reasons is the lack of knowledge of rocks capacity to deliver sufficient power on surface. More than 2 millions of scanned documents are available on the french geological survey. We propose a way to classify and analyze them in order to quantify the underground resource.


Japan Geoscience Union Meeting 2018
Presentation information
[EJ] Poster
[A-CG38] Science in the Arctic Region
convener:Shun Tsutaki(The University of Tokyo), NAOYA KANNA(Arctic Research Center, Hokkaido University), Shunsuke Tei(北海道大学 北極域研究センター, 共同), Tetsu Nakamura(Faculty of Environmental Earth Science, Hokkaido University)
[ACG38-P19] Influence of ocean bed geometry on the ice front variations of Bowdoin Glacier, northwestern Greenland
*Izumi Asaji1, Daiki Sakakibara2, Shintaro Yamasaki3, Shin Sugiyama4 (1.Graduate School of Environmental Science, Hokkaido University, 2.Arctic Research Center, Hokkaido University, 3.Kitami Institute of Technology, 4.Institute of Low Temperature Science, Hokkaido Univ.)
Keywords:Glacier, Greenland
The Greenland ice sheet(GrIS) is losing their mass due to reasons such as increasing surface melting and ice discharge from marine-terminating outlet(calving) glaciers. Especially in the southern area of the ice GrIS, mass loss from carving glacier were reported after 2000. This trend is also reported in the northern area of the GrIS in recent years. Bowdoin Glacier is a marine-terminating outlet glacier in northwestern Greenland (77°41'N, 68°35'W), the width of the terminal is about 3 km. The ice front had kept at the same position for 20 years, but the front has retreated rapidly since 2008. A hypothesis why this retreat occerd after 2008 is that the surface elevation of the glacier declined and therefore the buoyancy acting on the front of the glacier approached the gravity, as a result, the carving was promoted and a rapid recession occurred. However, the verification of this hypothesis is not sufficient, because there are few observations at the site in the northern area of the GrIS. In this study, in order to clarify the details of the bed topography and how much surface elevation was up to Flotation level (surface elevation at which gravity and buoyancy balance equilibrium to ice), we measured the bed topography of the fjord in front of the glacier and the surface elevation of the glacier. Then we discussed the flotation level by using, on-site observation and satellite data analysis on the Bowdoin glacier.
We measured the bed topography at the fjord in front of the Bowdoin glacier on July 29, 2016 by using a boat with a sonar and a transducer. The ice thickness at the glacier was measured using ice radar and the surface elevation of the glacier was measured by GPS kinematic survey at the same point. Surface elevation from 2001 to 2012 was also acquired from DEM (digital elevation model) created from images taken by optical sensors of artificial satellites Terra and ALOS. Then, we calculated the elevation of the bed topography under the glacier by subtracting the ice thickness from the surface elevation of the glacier.As a result, the depth in front of the glacier were 280 m in the west side and 180 m in the east side at maximum. The surface elevation of the glacier had declined at 2.8 m a-1 on average from 2001 to 2012. Comparing the surface elevation with the Flotation level, the glacial surface elevation in 2001 was more than 10 m higher than the Flotation level. However, the surface elevation was 0 - 10 m below the flotation level in the west side of the glacier in 2007. Therefore, the Bowdoin glacier has, reached a condition to float on water in a wide area on the west side of the glacier, and it might cause to greatly retreat the ice front.


text:
Over 8,000 websites created by students around the world who have participated in a ThinkQuest Competition.
Compete | FAQ | Contact Us
A Quest for New Land: The Oregon Trail
Follow along the Oregon Trail with the Hankin's family. Experience the life of a pioneer family with the trials and tribulations attributed to the Oregon Trail. Objectives: Students will learn the location and how the trail looked by navigating the virtual reality worlds. - By reading the journals, the students will be able to interact with the Hankin's family and the emotions they experienced. - By completing the quiz, the students will be able to test their knowledge of the readings. - Students will be able to do further research by clicking on the web pages. - Students will be able to understand what pioneer life was like by observing the pictures.
19 & under
Geography & Travel > North & Central America > United States
History & Government > United States

source: HuggingFaceFW/fineweb-edu


text:
a set of records. These pre-defined aggregate functions can be used only with scalar data. However, you can create your own custom implementations of these functions, or define entirely new aggregate functions, to use with complex data--for example, with multimedia data stored using object types, opaque types, and LOBs.
User-defined aggregate functions are used in SQL DML statements just like Oracle's own built-in aggregates. Once such functions are registered with the server, Oracle simply invokes the aggregation routines that you supplied instead of the native ones.
User-defined aggregates can be used with scalar data as well. For example, it may be worthwhile to implement special aggregate functions for working with complex statistical data associated with financial or scientific applications.
User-defined aggregates are a feature of the Extensibility Framework. You implement them using
ODCIAggregate interface routines.
Oracle9i Data Cartridge Developer's Guide for information on using the
Partitioning addresses the key problem of supporting very large tables and indexes by allowing you to decompose them into smaller and more manageable pieces called partitions. Oracle extends partitioning capabilities by letting you partition tables that contain objects,
REFs, varrays, and nested tables. Varrays stored in
LOBs are equipartitioned in a way similar to
The following example partitions the purchase order table along zip codes (
ToZip), which is an attribute of the
ShipToAddr embedded column object. For the purposes of this example, the
LineItemList nested table was made a varray to illustrate storage for the partitioned varray.
Nested tables are allowed in tables that are partitioned; however, the storage table associated with the nested table is not partitioned.
Assuming that the
LineItemList is defined as a varray:
CREATE TYPE LineItemList_vartyp as varray(10000) of LineItem_objtyp; CREATE TYPE PurchaseOrder_typ AS OBJECT ( PONo NUMBER, Cust_ref REF Customer_objtyp, OrderDate DATE, ShipDate DATE, OrderForm BLOB, LineItemList LineItemList_vartyp, ShipToAddr Address_objtyp, MAP MEMBER FUNCTION ret_value RETURN NUMBER, MEMBER FUNCTION total_value RETURN NUMBER ); CREATE TABLE PurchaseOrders_tab of PurchaseOrder_typ LOB (OrderForm) store as (nocache logging) PARTITION BY RANGE (ShipToAddr.zip) (PARTITION PurOrderZone1_part VALUES LESS THAN ('59999') LOB (OrderForm) store as ( storage (INITIAL 10 MINEXTENTS 10 MAXEXTENTS 100)) VARRAY LineItemList store as LOB ( storage (INITIAL 10 MINEXTENTS 10 MAXEXTENTS 100)), PARTITION PurOrderZone6_part VALUES LESS THAN ('79999') LOB (OrderForm) store as ( storage (INITIAL 10 MINEXTENTS 10 MAXEXTENTS 100)) VARRAY LineItemList store as LOB ( storage (INITIAL 10 MINEXTENTS 10 MAXEXTENTS 100)), PARTITION PurOrderZoneO_part VALUES LESS THAN ('99999') LOB (OrderForm) store as ( storage (INITIAL 10 MINEXTENTS 10 MAXEXTENTS 100)) VARRAY LineItemList store as LOB ( storage (INITIAL 10 MINEXTENTS 10 MAXEXTENTS 100)));
Parallel query is supported on the objects synthesized in views.
To execute queries involving joins and sorts (using the
SET operations) in parallel, a
MAP function is needed. In the absence of a
MAP function, the query automatically becomes serial.
Parallel queries on nested table columns are not supported. Even in the presence of parallel hints or parallel attributes for the view, the query will be serial if it involves the nested table column.
Parallel DML is not supported on views with
INSTEAD-OF trigger. However, the individual statements within the trigger may be parallelized.
Collection types do not map directly to a native type or structure in languages such as C++ and Java. An application using those languages must access the contents of a collection through Oracle interfaces, such as OCI.
Generally, when the client accesses a nested table explicitly or implicitly (by fetching the containing object), Oracle returns the entire collection value to the client process. For performance reasons, a client may wish to delay or avoid retrieving the entire contents of the collection. Oracle handles this case for you by using a locator instead of the real nested table value. When you really access the contents of the collection, they are automatically transferred to the client.
A nested table locator is like a handle to the collection value. It attempts to preserve the value or copy semantics of the nested table by containing the database snapshot as of its time of retrieval. The snapshot helps the database retrieve the correct instantiation of the nested table value at a later time when the collection elements are fetched using the locator. The locator is scoped to a session and cannot be used across sessions. Since database snapshots are used, it is possible to get a "snapshot too old" error if there is a high update rate on the nested table. Unlike a LOB locator, the nested table locator is truly a locator and cannot be used to modify the collection instance.


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Building a better maintenance schedule starts with understanding your assets and your resources, and how you can effectively bring the two together. This article looks at two core principles of PM scheduling, fixed and floating schedules, to help you better organize preventive maintenance.
Table of contents
Many everyday activities can be considered maintenance, from brushing your teeth to washing dishes. Most of these tasks are so routine, you barely think about how often you do them. Teeth are brushed at the same time every day and the dishwasher is run when it's full.
The same ideas guide preventive maintenance scheduling. Tasks are scheduled at certain intervals because it's what's best for the asset. But "what's best" for assets can differ. Understanding the difference allows you to coordinate PMs more effectively, build an efficient maintenance schedule, reduce the risk of downtime, effectively manage backlog, and control costs.
What are fixed and floating PM schedules?
Fixed PM scheduling is when regular maintenance is scheduled at a certain time or usage interval based on the target start date of the previous work.
For example, maintenance may be set up for a truck every 1,000 miles. A work order is triggered every 1,000 miles, regardless of when maintenance was last completed. That means that even if the previous PM was late (let's say it was done at 1,400 miles), the next PM would still be triggered at 2,000 miles. Fixed PMs can also be time-based. If that same truck is scheduled for maintenance every 10 days, a work order is sent out on the tenth day, whether the last PM was done on time, five days late, or not at all.
Building a better maintenance schedule starts with understanding your assets, your resources, and how to effectively bring the two together.
Floating PM scheduling is when preventive maintenance is scheduled based on the completion of the previous PM, the past usage of an asset, and the condition of the asset.
For example, a motor needs to be inspected after every 100 hours of operation. This maintenance might take place in a week or a month, depending on the production schedule. The next round of maintenance also changes if the motor is used differently. Maybe the motor is inspected after 120 hours of operation because a PM is done late. In this situation, the next work order for this PM would be triggered at 220 hours under a floating maintenance schedule.
When to use fixed PM scheduling
Fixed preventive maintenance scheduling doesn't work for every asset, nor does it work in every situation. There are a few scenarios when a fixed PM schedule works best and helps a facility use its resources efficiently while reducing downtime.
Maximizing labour and parts
Fixed PMs can help spread out tasks evenly for organizations with a large number of PMs. This makes it easier to plan labour and resources. Predictable tasks mean that the right number of staff and inventory (not too much and not too little) can be planned for a shift, day or week well in advance.
Creating effective schedules
If your facility has PMs that require shorter intervals, like daily or weekly, a fixed schedule is the easiest path to an effective schedule. It ensures that these tasks are completed consistently and on time, which is especially important when they're done on heavily used, production-critical assets.
Effectively managing warranties
Equipment manufacturers often recommend using a fixed PM schedule and can revoke warranties if these recommended schedules aren't followed. While you shouldn't completely base your maintenance schedule on warranties, it can be a factor, which makes sticking to a fixed schedule a good idea.
Meeting compliance regulations
Fixed PMs are generally more useful when certain assets or facilities are the focus of regulatory compliance or audits. Because a fixed schedule shows a predictable pattern, it is often seen as reliable proof that a facility is meeting certain regulatory benchmarks and is consistently giving attention to the necessary assets.
When to use floating PM scheduling
A floating PM schedule can be a more complex way to plan preventive maintenance and requires certain circumstances to work successfully. Certain assets and situations call for floating PMs more than others.
Increasing schedule flexibility
A floating schedule offers more flexibility for organizations with PMs that are spread over a long period of time and when those PMs can be late with minimal risk of failure or safety hazards. This flexibility allows the maintenance team to push PMs in favour of emergencies that have a huge impact on production.
Assessing risk and prioritizing tasks
Floating PMs are great for low-priority, routine preventive maintenance tasks that need to be completed on a regular basis, but won't affect the reliability or safety of equipment. In this situation, floating PMs allow the maintenance team to assess risk and prioritize tasks that matter most without an obligation to keep up with a strict schedule.
Coordinating maintenance and production schedules
A common use of floating schedules is for assets that are in high demand for production or service, but have a high degree of reliability and will not negatively impact safety or uptime if maintenance is late. The flexibility allows in a floating schedule means that unnecessary downtime can be reduced and uptime can be maximized.
How to use maintenance metrics to improve PM schedules
Asset type, asset history, and organizational processes determine whether you choose fixed or floating PMs for a piece of equipment. The next step is to set the frequency of these tasks. Maintenance metrics provide data to help you make this decision and optimize your schedule.
Mean time between failures
Mean time between failures (MTBF) helps establish how reliable an asset is and gets you closer to figuring out how long you have before that asset fails. This information can be used to shift PMs around and maximize time and resources without gambling with the health of equipment.
For example, an asset's MTBF may be 150 hours, but a preventive maintenance work order is created for the asset every 100 hours. It's apparent that the asset can be inspected less often, say every 125 hours. Having this information allows you to use time, labour, parts, and costs where they're needed more.
Preventive maintenance compliance
Preventive maintenance compliance (PM compliance) measures how successful your team is at completing preventive maintenance tasks. Keeping track of PM compliance for critical assets is one way to ensure time is being spent on the most important jobs and that you're not spreading the maintenance team too thin.
Tasks are scheduled at certain intervals because it's what is best for the asset. But "what's best" for assets can differ. Understanding the difference allows you to coordinate PMs more effectively.
For example, your facility's PM compliance on a critical piece of equipment might be 60%, which is very low. There are many potential reasons why PM compliance is low, but the most likely cause is a jam-packed schedule and not enough technicians to complete every task. In this situation, you can consider placing more technicians on these shifts or moving non-essential PMs to another day.
Maintenance cost as a percentage of replacement asset value
Maintenance cost as a percentage of replacement value (MPRAV) is one way to calculate if the value of an asset is worth the number of maintenance resources being given to it. A culture of total productive maintenance and better maintenance processes can reduce MPRAV and have an indirect, but huge, impact on PM scheduling.
For example, one of your assets might break down a lot. You're spending more time (and money) on PMs to reduce the frequency of failure. This puts a strain on the maintenance schedule. Calculating MPRAV helps you visualize these inefficiencies and find alternatives, like investing in new equipment, higher-quality parts, and better training. This leads to fewer breakdowns and less frequent PMs, leaving more time and money for other assets and PMs.
The bottom line on preventive maintenance scheduling
Every facility has unique assets, production schedules, and maintenance teams. That's why every facility will schedule its PMs a little differently. However, there are some tried and true methods for structuring and optimizing a PM schedule. This includes using fixed and floating schedules and metrics to bolster PM scheduling. When maintenance operations can apply these concepts to their schedule, it empowers them to cut costs, eliminate inefficiencies, use labour more effectively, and increase uptime.


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- addle (v.)
- 1712, from addle (n.) "urine, liquid filth," from Old English adela "mud, mire, liquid manure" (cognate with Old Swedish adel "urine," Middle Low German adel, Dutch aal "puddle").
Used in noun phrase addle egg (mid-13c.) "egg that does not hatch, rotten egg," literally "urine egg," a loan-translation of Latin ovum urinum, which is itself an erroneous loan-translation of Greek ourion oon "putrid egg," literally "wind egg," from ourios "of the wind" (confused by Roman writers with ourios "of urine," from ouron "urine"). Because of this usage, from c.1600 the noun in English was taken as an adjective meaning "putrid," and thence given a figurative extension to "empty, vain, idle," also "confused, muddled, unsound" (1706). The verb followed a like course. Related: Addled; addling.


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Elementary Matrices Generate the General Linear Group
Okay, so we can use elementary row operations to put any matrix into its (unique) reduced row echelon form. As we stated last time, this consists of building up a basis for the image of the transformation the matrix describes by walking through a basis for the domain space and either adding a new, independent basis vector or writing the image of a domain basis vector in terms of the existing image basis vectors.
So let's say we've got a transformation in. Given a basis, we get an invertible matrix (which we'll also call ). Then we can use elementary row operations to put this matrix into its reduced row echelon form. But now every basis vector gets sent to a vector that's linearly independent of all the others, or else the transformation wouldn't be invertible! That is, the reduced row echelon form of the matrix must be the identity matrix.
But remember that every one of our elementary row operations is the result of multiplying on the left by an elementary matrix. So we can take the matrices corresponding to the list of all the elementary row operations and write
which tells us that applying all these elementary row operations one after another leads us to the identity matrix. But this means that the product of all the elementary matrices on the right is. And since we can also apply this to the transformation, we can find a list of elementary matrices whose product is. That is, any invertible linear transformation can be written as the product of a finite list of elementary matrices, and thus the elementary matrices generate the general linear group.


What is C-RAN? The Evolution From D-RAN to C-RAN
By Sean Hsu
what is CRAN title image
Who came up with C-RAN?
Centralized Radio Access Network or C-RAN, was first introduced by the China Mobile Research Institute in 2010 in an effort to create a new cloud computing architecture for supporting a the 5G Mobile network. C-RAN breaks apart the traditional cell-based network infrastructure into separate parts that meet the requirements of 5G, while supporting the existing 2G, 3G, and 4G infrastructures. It includes a centralized processing, collaborative radio, and real-time radio networking.
The Building Blocks of RAN
Telecom base station
Picture of a telecom base station.
Traditionally, a Radio Access Network (RAN) consists of a group of Base Stations (BS) or NodeB (NB), usually sprinkled on top of buildings to form a cell network, which provided wireless access to mobile users. It is composed of an antennas, radio frequency (RF) equipment, digital processors, and baseband units.
The base stations are used to interconnect phone signals between a user's device and the core network. When a mobile device is connected to the nearest cell tower, it was the base station's job to transmit the traffic (voice, data, video traffic) to the core network owned by the telecom company.
Telecom base station components
Parts of a telecom base station.
The base station is made up of two separate parts that will function individually called the Baseband Unit (BBU) and the Remote Radio Unit (RRU) or Remote Radio Head (RRH). When the signal arrives at the base station, the RRU retrieves the signal or radio frequency from the antenna and creates the analog transmitted RF to the baseband unit. Then the BBU refers to the original frequency range of a transmission signal before it modulates, generates, and processes the digitalized signal. Functions such as de(coding) and de(modulation) are done in this part as well. In other words, BBU handles most of the digital processing while the RRU takes care of the analog side of things. The combination of both units at the cell site is called a Distributed-RAN (D-RAN) architecture.
Beginning from D-RAN
In a D-RAN architecture, the whole base station is located at the cell tower site. The RRUs are located at the top of the tower next to the antennas and the BBUs are located in an equipment room not too far from the tower itself. The RRUs and BBUs are directly connected via CPRI or Common Public Radio Interface, meaning that for every one RRU there will be one BBU connected to process the data.
Example of D-RAN
Although simple, D-RAN presented several issues for telecoms especially in terms of managing the space and capacity needed at the base stations. Most of the base stations were deployed to meet peak capacity periods for that region. However, peak periods come and go, so there were often be times where that processing capacity was underutilized. There's also the issue of the need to meet short bursts of traffic (for example, if there's a concert or event nearby), the RRUs and BBUs were not designed for this type of flexibility.
CRAN: BBU Pooling and Virtualization
Example of C-RAN
In a C-RAN architecture, the base station is split up. The RRUs stays at the cell site, while the BBUs are aggregated into a centralized office, sometimes called a BBU hotel, with a centralized controller to process calculations digitally. This concept breaks the 1:1 connection between RRU and BBU, virtualizes the heavy-loaded baseband calculation, and brings key functions to the central office, which is much closer and convenient for the telecoms to manage. Also, by aggregating all the BBUs, telecoms can better organize their computing resources, which can reduce the costs on the maintenance of the 5G network.
The virtualization technologies facilitate the logical isolation of resource while the physical resources are shared in dynamic and scable way. In the context of C-RAN, network virtualization is done at the BBU pool level including network, computing and storage. Each BBU is a virtual node while the communication between them are virtual links. The pool operates on one machine sharing CPU, memory and network resources between multiple BBUs.
Advantages of Centralized BBU in C-RAN (BBU pooling)
Centralizing the BBUs come with several advantages, including resource virtualization, better service deployment at the edge and the potential to utilize advanced technologies that require high processing power. With BBU pooling, joint processing and cooperative radio sharing will become possible.
In the traditional network, the BBU is located far from the central office usually spanning across several roof tops or at the cell tower, which are difficult or costly to maintain. As BBUs are brought closer to the central office, they can potentially be placed inside secured data centers. This would improve data security and would allow for more efficient data processing for more extensive computations. With multiple BBUs sharing a common processing pool, its resources can be utilized more effectively with less power consumption and as well as allowing access to larger amounts of resources when needed.
Lastly, by pulling together resources at central offices, services can be deployed on the network edge instead of the core. By moving service closer to the user, telecoms gain faster responses with edge computing while reducing the bandwidth needed for backhaul traffic.
The Fronthaul Network Transition to 5G C-RAN
With 5G, the design of BBU pooling is faced with another issue. The transport requirements of 5G vastly surpasses that of 4G. Here are some of the differences between 4G and 5G.
4G vs 5G
Meeting the requirements of 5G meant changes had to be made to the fronthaul network, in particular the use of CPRI between RRUs and BBUs. The CPRI standard defines an interface between the Radio Equipment Control (REC) and the Radio Equipment (RE), which is mostly used to carry data between cell sites and base stations. Since, CPRI was not designed to meet the timing, latency or efficiency requirements of 5G, eCPRI was developed specifically for 5G fronthaul transport.
Fiber is the preferred choice recommended from the C-RAN community due to the higher bandwidth requirement, however, cellular or millimeter wavelength do offer cheaper and easier deployment, but at higher latency.
5G from C-RAN toward O-RAN
Past RAN architectures (3G/4G) constructed their NodeB (NB) and eNodeB (eNB) based on monolithic building blocks. However, 5G introduced massive MIMO (multiple-input, multiple-output) to overcome the high data rate and low latency requirements. It combined the RRU and the antenna into an Active Antenna Unit (AAU), which hangs on top of the antenna system. This reduced the signal loss caused by the transmission of multiple antennas to the RRU.
BBU split into CU DU
Within the 5G RAN, the BBU can be split into the Distributed Unit (DU) and the Centralized Unit (CU). The DU runs close to the RRU and is responsible for real-time Layer 1 (Physical) such as OFDMA and MIMO as well as the Layer 2 scheduling functions such as RLC (Radio Link Control) and MAC (Media Access Control). RLC contains ARQ and HARQ to support the re-transmission functions and the MAC mainly provides QoS (Quality of Service) features.
The logical node includes a subset of the eNB/gNB functions, depending on the functional split option, and its operation is controlled by the CU. The CU is a centralized unit connected between the 5G core network and the DUs. It provides the access control and coordinates high-level protocols including RRC (Radio Resource Control) from the control plane and IP, SDAP (Service Data Adaptation Protocol), PDCP (Packet Data Convergence Protocol) from the user plane. SDAP is a new protocol aimed at the QoS flow for the user's access to the 5G network. PDCP compresses and decompresses the IP headers and maintains the wireless payload integrity of the sequence.
To lower cost, improve performance, and scale up baseband processing from the base station, C-RAN has come to the center stage. It separated the BBU and RRU from the base station. It centralized the BBU into a shared resource pool for heavy computation with virtualization from the cloud. It removed the real-time function from the BBU and integrated it into an AAU box. Furthermore, the pooled resources makes it easier to deploy services at the edge, which improves user satisfaction, improves resource utilization, and reduces the pressure of backhaul traffic.
In this Article: 5G RAN


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Dilute Particle Suspension Effects
The liquid preparations utilized in this study were suspensions more dilute than are customarily employed. The investigations disclose insights not apparent from the experimental results garnered from more concentrated suspensions. Dilute suspensions represent worst-case situations, those least encouraging to particle retentions.
In more concentrated suspensions it is conceivable that so large a number of smaller particles may simultaneously arrive at a pore/fiber matrix as to give the appearance of its immediate blockage by a larger particle. This would result in a more rapid reduction in the number of larger pores, reducing over time the opportunities for smaller particles to penetrate them. It is a matter of the rate at which a sufficient mass of smaller particles reaches the larger pores to block them, and of the number of individual smaller particles that escape capture during the period of time leading up to the blockage.
The period during which the larger pores are available for penetration by the separate smaller particles of dilute suspensions is foreshortened in the case of concentrated dispositions, where more sudden pore blockages take place. Thus, the same total number of particles impacting a membrane over different durations can yield different throughputs. In essence, the diluter suspension represents the worst-case condition in that it makes more likely the escape of the smaller individual particles through still-unclogged larger pores.
As a result of the above discussion, it is posited that the coincidence of pores and particles can perhaps better be perceived when investigated in suspensions of dilute concentrations.
American Society for Testing and Materials (ASTM), ASTM Standard F-316-03 -2003. "Pore-Size Characteristics of Membrane Filters for Use with Aerospace Fluids," ASTM, West Conshohocken, PA.
Emory S.F., Koga, Y., Azuma, N., Matsumoto, K. (1993). The Effects of Surfactant Type and Latex-Particle Feed Concentration on Membrane Retention, Ultrapure Water 10(2): 41–44.
Grant, D.C. and Zahka, J.G. (1990). Sieving Capture of Particles by Microporous Membrane Filters from Clean Liquids. Swiss Contamination Control 3(4a): 160–164.
Lee J.K., Liu B.Y.H., Rubow K.L. (1993-a). Latex Sphere Retention by Microporous Membranes in Liquid Filtration. J. Inst. Environ. Sci. 36(1): 26–36. (Jan./Feb).
Lee J., Liu B.Y.H., Rubow K.L. (1993-b) Latex Sphere Retention by Microporous Membranes in Liquid Filtration. J. Inst. Environ. Sci. 36(1): 26–36.
Lee, K. W., and Liu, B. Y. H. (1980). On the Minimum Efficiency and the Most Penetrating Particle Size for Fibrous Filters. Air Poll. Control Assoc. J. 30, 377–381.
Lee, J.K., Liu. B.Y.H., Rubow, K.L., and Zahka, J.G. (1990). Pore Size Characteristics of Microporous Membranes and Filters by Airflow Porosimetry and Particulate Loading Studies. Swiss Contamination Control. 3: 160–164.
Zahke, J.G. and Grant, D.C.(December 1991). Predicting the Performance Efficiency of Membrane Filters in Process Liquids Based on Their Pore-Size Ratings. Microcontaminants. pp. 23–29.
Zeman, L.J. (1996). Characterization of MF/UF Membranes. Chapter 4, pages 180–291 in Microfiltration and Ultrafiltration: Principles and Applications, Eds L.J. Zeman and A.L. Zydney, Marcel Dekker, New York, NY.


text: Contact angle hysteresis (CAH) has important implications in a variety of natural and industrial applications. The contact line motion of Cassie drops on microtextured surfaces is directly visualized using high-magnification imaging and fluorescence microscopy. The advancing contact line is observed to glide smoothly over the micro-posts, whereas the receding contact line exhibits significant stick-slip. Using simultaneous measurements of drop width and contact angle, the authors quantify stick-slip amplitude and define contact width hysteresis. A new scaling is proposed for drop roll-off angle α wherein sinα is linearly proportional to the practical work of adhesion (1 + cosθr). This study provides insight into the dynamic nature of CAH and the design of superhydrophobic surfaces with optimal drop shedding.


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Exploration of advanced theoretical, methodological and empirical issues in health psychology.
Health psychology is a diverse field of research that addresses the role of psychological processes in health and illness as well as the provision and receipt of healthcare. This paper provides an advanced introduction to health psychology. As a student in this paper you will develop an understanding of some major ideas and debates within health psychology, learn to critically evaluate the evidence for those ideas and debates, and develop your skills in academic writing, working in teams, and giving oral presentations.
|Paper title||Advanced Topics in Health Psychology|
|Teaching period||First Semester|
|Domestic Tuition Fees (NZD)||$666.57|
|International Tuition Fees (NZD)||$2,895.09|
- PSYC 470
Entry into Psychology 400-level normally requires a major in Psychology, a B+ average or higher in Psychology 300-level papers, and a pass in PSYC 311 Quantitative Methods. We highly recommend that students have completed PSYC 310. Students from other universities must show evidence of an equivalent level of competence.
- More information link
- Teaching staff
Lecturer: Associate Professor Gareth Treharne
- Paper Structure
- Research methods in health psychology
- The psychology of health promotion
- The psychology of screening programmes
- Health psychology and sexual health
- Health psychology and gender transitioning
- Health psychology and cultural diversity
- The psychology of illness perceptions
- The psychology of adherence to treatment
- Health psychology and pregnancy
- Health psychology and end-of-life care
- Weekly reading critiques (500 words): 50% (10% for the best 5)
- Oral presentation (10 minutes): 10%
- Examination (2 hours): 40%
Required: Articles will be set on a weekly basis.
Recommended: Lyons, A. C., & Chamberlain, K. (2006). Health psychology: A critical introduction. Cambridge: Cambridge University Press.
- Graduate Attributes Emphasised
- Communication, Critical thinking, Cultural understanding, Ethics, Information literacy,
Research, Self-motivation, Teamwork.
View more information about Otago's graduate attributes.
- Learning Outcomes
By the end of the paper, PSYC 423 students should be able to:
- Demonstrate awareness of the key theories and empirical findings across a range of advanced topics in health psychology.
- Understand how a range of psychological research methods are applied ethically in health psychology research.
- Demonstrate awareness of the nature, causes and potential solutions to health inequalities across culture, gender, sexuality and other aspects of identity.
- Critique existing research, conduct independent searches to find and synthesise diverse research findings in health psychology, and articulate these points in concise, well-argued written work.
- Give a short oral presentation about a piece of research, debate the findings of existing research, and effectively present innovative ideas for future research.


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Chicago's Willis Tower, formerly known as Sears Tower, was the world's tallest building from 1974 to 1998 and remains the tallest building in the U.S. to this day. Its 1451-foot (442 m) height adds up to enough window area to keep a window washer busy for life, or space for enough solar panels to be comparable to a 10 acre solar power plant. As part of a pilot project, the south facing windows of the 56th floor of the Willis Tower will be replaced with Pythagoras Solar's transparent solar windows which cut down on heat gain – and therefore cooling costs – as well as harnessing energy from the sun.
While the image that comes to mind when one thinks of solar power plants is probably one of rows upon rows of panels covering large areas of desert, replacing the windows of skyscrapers with solar windows gives cities with limited free space the opportunity to create vertical solar power plants. Pythagorus Solar's solar windows, which the company calls photovoltaic glass units (PGUs), are rectangular box-shaped units that allow diffused light to pass through, but use a prism to reflect sunlight down onto a horizontal PV cell along the bottom of the unit to generate the same amount of energy as standard rooftop-mounted solar cells.
"We are excited to launch this pilot with Pythagoras Solar's leading-edge solar window solutions as a test for not only the energy savings that can be achieved, but the potential they represent to actually generate power through the sun," said John Huston, Executive Vice President of American Landmark Properties, one of the ownership partners of Willis Tower.
If the pilot project proves successful, Pythagoras Solar's PGU's could be expanded beyond the 56th floor to cover enough surface area to provide over two megawatts of solar power.
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WE'RE WORKING TOGETHER
We are hopping to begin a program where we will provide memory boxes in the A&E department of hospitals. Our memory boxes will be our way to help ease the suffering, by allowing parents/carers to create their own special and precious memories of their child.
No parent can ever imagine the pain and heart wrenching suffering they feel when being told that their baby has died. The shock and numbness is unimaginable and nothing can prepare you for the grief. The boxes will guide parents through the initial steps of this tragedy and allow them to gather precious keepsakes and create a memory box, which will provide them with timeless memories.
Our goal is to provide bereavement boxes to parents who has suffered the tragic loss of a child. The boxes contain baby grows and blankets as often their clothing will have been removed and its important for parents to see their baby looking clean and cared for after such loss, a loving handmade blanket are provided to keep baby safe. Other items and vital information are included to help steer them through the next steps in the coming weeks. The box also contains items that aim to give parents a chance to create their most precious lasting memories.
An additional Jummy (soft toy elephant) will be provided for siblings in the hope they will find comfort in having the same toy left with their baby brother or sister.
What is the difference between a Bereavement and a Memory box
The box is just a container and is designed in such a way to be both the first step bereavement point and then be used to keep our lasting memories.
We hope that we have approached this delicate but important step in a way, not to offend but as a a parent who has gone through the darkness and wants to help. We do this by encouraging parents to make memories, each memory is truly important; even the smallest gesture can mean the world. A Memory Box is often described as a parent's most treasured possession.


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A chilling image, but can it be right that the column would be 269 miles long?
The dead are marching four abreast so 1,104,890 divided by 4 gives 276,222 rows. There are 5,280 feet in a mile and 1,420,320 feet in 269 miles. If we divide 1,420,320 by the 275,222 rows it gives 5.142 feet for each row. That sounds about right. If marching men are too close together they would be constantly stumbling into each other.
So, the marching war dead of the British Empire [Britain, Canada, Australia, New Zealand, India and other smaller countries] would produce a column 269 miles long.
In the top right hand corner of the image there is a small yellow box. This gives equivalent distances for other Empire countries. For example, the column would stretch from Quebec to Ottawa. It also gives the time needed for the column to march past the Cenotaph war memorial in London. I cannot read the number but it is easy to calculate.
British Army Field Service Regulations gives a infantry marching speed of 294 feet per minute [3.3 miles per hour]. At that speed it would take 18 minutes for one mile of the column to pass the Cenotaph and 18 x 269 = 4,842 minutes [3 days, 8.6 hours] for all the column to pass.
Similar columns for the total military dead [casualty figures from Wikipedia] for other countries.
France 340 miles [127% of the BE figure]
Germany 486 miles [181% of the BE figure]
USA 28 miles [10.4% of the BE figure]
On the 1st July 1916, the first day of the Battle of the Somme, the British Army suffered 57,470 casualties, including 19,240 dead. The dead from that day would form a column 4.68 miles [7.53 kilometres] long.


Water Purification In The Wilderness
Water Purification In The Wilderness
Water purification in the wilderness and on extended fishing trips is a critical skill to master.
It is commonly known that the more remote a fishing spot is, the more likely it is to be a good one. When it is easy to get to a particular fishing location, that means more people will likely visit that spot. This means fish will be spooked and concentrations will be smaller. There is something to be said for hiking or boating to virgin waters for a prime fishing experience.
Hydration can be an issue when fishing remotely for several days. There is a good chance you will be doing lots of hiking or paddling in the hot sun. Wading also can wear you out and dehydrate you. On trips like these, carrying drinking water is tough. Water is heavy and can really weigh down your pack.
The best solution is to purify water as you go. Since you are on a fishing trip, you should be near a good-sized body of water. However, drinking that water without purification could make you very sick. In this article, we will cover ways to safely stay hydrated in the wild without carrying drinking water.
Why Hydrate?
The Survival Rule of Threes states that the average person can survive about three days without water under normal circumstances. However, wilderness fishing trips are not normal circumstances. You will be spending lots of time in the sun working hard to get to the right fishing spots. This shortens your window. You may only survive a day or two without water.
In addition, the side effects of dehydration kick in almost immediately. You will notice that you become weaker and get winded easier. You might be light-headed or dizzy, and headaches are common. Then come cold sweats, dry mouth, and heart palpitations. Your last warning sign is if you pass out or stop sweating.
I have experienced severe dehydration several times, and it makes basic tasks very difficult. When I am fully hydrated, I can walk three or four miles with a heavy pack before I want a break. When dehydrated, I may only make it a few hundred feet before I need to sit down or even lie down. It just sucks all of the energy out of you, and it feels like your heart is going to beat out of your chest. You should start regularly hydrating as soon as you start your adventure, and never wait until you are thirsty to drink.
Why Purify?
Most water sources in the wild will contain tainted water full of debris, bacteria, and other pathogens. The warmer the water temperature is and the more stagnant it is, the more likely it is to make you sick. Drinking this water can cause vomiting and diarrhea which would only dehydrate you faster. The only time you should ever consider drinking tainted water is if you have already gone several days without water and have absolutely no way to purify it. At this point, you just need to hydrate enough to survive a few more days. Many waterborne pathogens take a few days to really start affecting you.
There are a few exceptions to this rule. If you have clean chunks of ice to melt, it should be okay to drink. You should avoid snow as it is 90% air and 10% water. Springs are spots where water spews directly out of the ground after being purified by the earth itself. This is safe to drink as long as it does not smell funny. Mineral deposits are still possible in springs. If you can set up a rainwater catchment system, it is safe to drink most rainwater. Finally, there are plants like coconuts and watervines that can be safe sources of water.
By far the best option for purifying water is a filter. Modern water filters eliminate 99.999% of all harmful pathogens. You can use a straw style filter to save space in your pack. Just be prepared to get on your belly to drink unless you have a container for water. I prefer filter bottles as they allow me to fill up and then drink as I go until I fill up again. You can also get gravity fed filters with rubber bladders that hold several gallons of water. These are ideal if you will be camping in the same spot for several days, or if you have a group of people using one filter.
One of the oldest methods for purifying water is to boil it over a heat source. Chances are you will have a campfire or a camp stove of some kind, so boiling water just takes a few minutes. We were once told that the water must boil for a long time to make it safe, but we now know you just need to bring it to a boil and then let it cool. This does not remove debris, so filter as well if possible.
Iodine Tablets
I typically carry iodine tablets with me in the wild because it is common for my water filters to become clogged with debris. Sometimes I can fix them, and sometimes I cannot. If it rains, fire can be a problem as well. This leaves plan C. A vial of iodine tablets can purify about 25 bottles of water and will easily fit in any pocket. Just drop two in a bottle of water, shake it up a few minutes later, and you can drink in 30 minutes. You can use bleach to accomplish the same thing, but I prefer not to pack liquid chemicals-plus you have to be careful to make sure that your measurements are correct, or you could end up poisoning yourself.
Other Options
If none of the previously mentioned methods can be performed, you still have a few steps you can take. None of these purification methods are ideal, but they are much better than doing nothing or not hydrating. You can layer gravel, sand, and charcoal in a bottle to make your own water filter. Just tie some cloth over the opening at the bottom to remove debris. You can set clear water out in the sun in plastic bottles for six or more hours to kill most pathogens with UV light. You can also dig a proximity well next to a body of water and hope that the earth will filter out most of the pathogens.
As you can see, hydration is something to take seriously. If you or someone in your group becomes dehydrated, you could end up in a wilderness survival scenario instead of a fishing trip. If you see signs of serious dehydration, try to call for help. Sometimes an IV of fluids is the only way to bring someone back. If this is not possible, sip lukewarm water in the shade and put a wet cloth around your neck. Hopefully, this discussion will help you stay hydrated throughout your whole trip.
Water Purification Is Important But Must Be Approached Carefully
Please note that these are basic tips and advice regarding water purification. Please follow all local regulations and understand the affects that various chemical treatments can have on your health. Water purification isn't something you can afford to get wrong.
Questions? Concerns? Contact us here!
You can find out a TON of great information about backpacking trips in Michigan from Jim DuFresne's classic book, Backpacking In Michigan (You can find it here) (Yes, it's a classic).
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Astellas has been conducting collaborative research with the Institute of Medical Science, the University of Tokyo (IMSUT) on the rice-based oral vaccine MucoRice against diarrheal diseases caused by cholera, enterotoxigenic Escherichia coli (E. coli), norovirus, etc. since the execution of a new collaborative development agreement in June 2016.
In developing countries, diarrhea caused by pathogenic bacteria, such as Vibrio cholera and enterotoxigenic E. coli, is a major cause of death among infants and young children. However, vaccines present several issues, such as the need to store and transport existing cholera vaccines at a constant low temperature, and the fact that vaccines against enterotoxigenic E. coli have not been approved in developing countries.
There are high hopes that MucoRice could be stored at room temperature. Therefore, if the challenges are overcome, it will not require the strict temperature management that is usual for the storage of biopharmaceuticals. The establishment of cultivation techniques that enable efficient production should help reduce medical expenditures for the vaccine.
In December 2017, Astellas, IMSUT, Chiba University and ASAHI KOGYOSHA CO., LTD. signed a collaborative research agreement aimed at the practical application of MucoRice-CTB, a rice-based oral vaccine that expresses the Cholera Toxin B subunit (CTB) in the rice storage protein. Under the agreement, Astellas will examine the conditions for production and formulation of MucoRiceCTB. Meanwhile, IMSUT, Chiba University, and ASAHI KOGYOSHA will develop the production system for the vaccine. This research program has been designated as a project under Cyclic Innovation for Clinical Empowerment and will be supported by the Japan Agency for Medical Research and Development.
Through these collaborative research projects, Astellas will attempt to develop new platform technology to create innovative new drugs to address unmet medical needs.


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Ask-A-Linguist Message Details
Is it possible to compare the speed at which different languages are
normally spoken? If so, which languages are relatively fast and which
In addition to all the above,'syllables' do not necessarily do the same amount of semantic work (on average) in different languages. For example, in Chinese (nearly always) each syllable is a morpheme, whereas in English there are many morphemes of more than one syllable. This means that (for this and other reasons) the average number of syllables taken to say the'same' thing will be higher in English than in Chinese. The way languages organise their grammar affects the number of syllables in a proposition.
In addition, there are large individual differences between speakers of the same language (even of the same dialect).
It has also been suggested that, within the same language, on average, rural speakers speak slower than urban ones. What if one language was used predominantly by rural communities and another by urban ones? Is that to do with the language or to do with the rural/urban divide.
Formal delivery may be slower than informal too. Recitation styles may be exceptionally slow or exceptionally fast.
In other words -- it's an interesting question that raises many methodological questions and is linked to all sorts of cultural stuff.
|Reply From:||Anthea Fraser Gupta click here to access email|


itself can fail around the mounting flange, or, more often, the weak 8.8(grade 5) grade bolt holding the gear can break. It is strongly recommended to use a 10.9 (grade 8) grade bolt when replacing the oil pump gear. Another cause for timing belt failure is improperly adjusting the timing belt on engines with a manual tensioner (1989 to very early 1990 models only) or improperly adjusting the balance shaft belt. Because this is an interference engine, damage will occur if the timing belt fails. Another common occurrence is that the balance shaft's oil seals are prone to leak on older engines. New replacement sealings tend to start leaking again due to 'worn in irregularities' on the shaft itself. Many people have removed the balance shaft belt or the balance shaft assemblies altogether to prevent belt failure and/or leakage. The balance shafts are only there to lessen vibration for a smooth idle, and removing them will not harm the engine. Once all the common problems are solved, the 16 Valve engines are just as reliable as their SOHC counterparts.
The recommended timing belt interval for these engines is every 50,000 miles, or earlier if the engine is modified. It is also recommended to replace the crank and camshaft seals at every interval and to thoroughly inspect the tensioner and idler pulleys for wear.
Volvo Penta[edit]
Volvo Penta sold the OHC redblocks as marine engines as well, just like the older OHV engines. Depending on the model the displacement was 2127 (as B21), 2316 cc (same as B23/B230 automotive) or 2490 cc. The engines with 2490 cc displacement, identified as the Volvo Penta AQ151 (8 valve) and AQ171 (dohc 16 valve) models, got a forged crankshaft with a longer stroke (86 mm stroke) together with pistons with a 3 mm (0.1 in) lower compression height. The 2490 cc blocks still had B230 cast in the block. Penta used both the 8 valve and 16 valve cylinder heads. Both the 8V and 16V variants used the same engine block series, the 16V versions didn't use the different block like the automotive B2x4 with balance shafts.
The B21, and related red block motors, were named using the following convention: B##X or B##VX. Where B stands for "bensin" (gasoline), ## stands for the displacement in decilitres, and X is an appropriate suffix. On the later low-friction motors, V denotes SOHC configuration (0) or DOHC configuration (4, for 4 valves per cylinder).
i.e. B230 (SOHC, 2.3 litres), B234 (2.3 litres, DOHC * 4 valves per cylinder * 4 cylinders = 16 valves)
The following suffixes were commonly used by Volvo:
 - A - single constant-pressure type carburetor (such as the Pierburg 175 CDUS), typically with manual choke
 - B - high compression, with twin carburetor's, either twin zenith-strombergs or twin SU's.
 - E - high compression, no catalyst, mechanically fuel injected k-jetronic
 - BxxET - K-jetronic turbo
 - B2xxET - Motronic controlled electronic fuel injection, turbo.
 - F - low compression (9.8:1 on B230F, 9.5:1 on B280F, 10.0:1 on B234F and 10.7:1 on B6304F), USA/Europe version (F for Federal) with catalytic converter. Europe/APAC version, fuel injected (usually LH Jetronic or Bendix Regina)
 - K - single jet type carburetor (such as the Solex-Cisac carbs), typically with automatic choke
 - G - LH2.4 Jetronic but without cat. converter, CO adjustment on the AMM (similar to LH2.2 Jetronic). Some models without O2 sensor, others with O2 sensor which requires regular replacement at intervals due to lead fouling. For markets which unleaded fuel was rare in the early 90's, e.g. Eastern Europe
 - FB - low compression version of B230F (9.3:1) with the "531" cylinder head and VX3 camshaft, power output 11 kW (15 PS; 15 hp) and 2 N·m (1.5 lb·ft) more than B230F. LH2.4 Jetronic fuel injection, for European markets.
 - FD - essentially a B230F fitted with Exhaust Gas Recirculation (EGR) and Pulse air system for cleaner emissions
 - T - turbocharged, after E or F suffix (example: B21ET, B230FT)
 - FK - low pressure turbo, 1995 onward, not supplied in North America. Identical to the B230FT engine of that time but lowered boost level (4 PSI)
 - FT - LH-jetronic 2.2/2.4 Turbo
 - FTX - Higher power output B230FT (approx 190 hp)
See also[edit]
External links[edit]


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We have a great amount of flexibility with post-frame buildings. Their designs offer attractive features such overhangs, steeper roof pitch, porches, etc. Because their walls don't require interior supporting walls, you have open space inside to configure any why you want. You also get a lot of flexibility when it comes to exterior walls as well. It doesn't have to be steel. Almost any type of façade can be used like brick, blocks, vinyl and wood siding.
Most people are surprised to learn that post-frame buildings have more strength than other building methods. There are a number of reasons for this:
- Columns in the ground add a lot of stability and wind resistance to a building.
- Horizontal connected posts from an extremely strong box that adds to wind and seismic resistance.
- The direct attachment of trusses to post frame buildings gives them a virtually impossible for a roof to detach from the building.
- The Diaphragm effect that is created by the post-frame structure allows them to flex under extreme stress instead of cracking or collapsing like would happen with other structures.
Source: "The Post-Frame Advantage: It's Long-Lasting and Resilient." Frame Building News, January 2003.


Tesla's New Tabless Batteries Unlock New Levels Of Performance
Telsa are one of the world's biggest purchasers of batteries through their partnerships with manufacturers like Panasonic, LG and CATL. Their endless hunger for more cells is unlikely to be satiated anytime soon, as demand for electric cars and power storage continues to rise.
As announced at their Battery Day keynote, Tesla has been working hard on a broad spectrum of projects to take battery technology to the next level in order to reach their goal of 3 TWh annual production by 2030. One of the most interesting aspects of this was the announcement of Tesla's new tabless 4680 battery, which will be manufactured by the company itself. Let's take a look at what makes the 4680 so exciting, and why going tabless is such a big deal.
Roll Up, Roll Up
A diagram showing a typical cylindrical cell design, with tabs to connect the anode and cathode to the cell casing.
Tesla are somewhat unique among electric car makers in that they've resolutely stuck to using cylindrical cells in their battery packs, where other manufacturers have largely used prismatic designs. Beginning with the venerable 18650 popular with laptop manufacturers and flashlight builders, Tesla later moved on to using larger 21700 batteries, with the bigger form factor meaning each cell had greater capacity. To construct these cells, long, thin sheets of anode and cathode material are laid on top of each other with a seperator material in between, and then rolled up into a "jellyroll" to fit inside the cylindrical body. The anode and cathode each have a small tab, generally at the center of the rolled up sheets, which pass power to the terminals on the outer case of the battery.
These small tabs hold back cylindrical cells in a multitude of ways. They act as a bottleneck for current flowing in and out of the cell, as despite the huge area of the anode and cathode, all current flowing in and out of the battery must go through a pair of tabs just a few millimeters wide. Electrons from the outer areas of the jellyroll must travel a significant distance to reach the cell terminal, with an electrical path length up to 250 mm in 21700 cells. This greater path length means more resistance, with a corresponding effect on thermal performance. Additionally, the tabs frustrate efforts to effectively produce anode and cathode sheets at speed, with production machinery having to stop and start repeatedly to deal with the protruding features.
Tesla modelled the impact of cell size on charging times, which is a major problem with classical batteries using tabs. The new tabless design helps solve this issue thanks to improved thermal performance.
Tesla had previously made gains in performance when shifting from 18650 cells to the larger 21700 design, but efforts to further increase cell size hit a brick wall. While larger cells can store more energy and deliver cost savings in production, thermal issues meant that charge times and discharge rates would be negatively impacted. Larger cells meant longer path lengths, with the higher resistance meaning less power output per cell and slower charging. Even with Tesla's fast charge technology, many still consider electric cars to charge too slowly, so this was one tradeoff that wasn't worth making.
The "shingled spiral" of the jellyroll in a tabless battery. Instead of one tab in the center of the jellyroll, the entire base enables current to flow to the active material.
Enter "tabless" batteries. Rather than having a small battery tab attached to the anode and cathode respectively, the entire anode and cathode foils are laser-patterned and processed to have what are essentially many tiny tabs all along their length. Replaces the step of manually attaching separate tabs later in the manufacturing process.
When the anode, cathode and separator are all rolled up together, these many smaller tabs flatten out to form a "shingled spiral", creating a much larger contact area between the active battery material and the casing. This means that the path length for electrons to travel is much reduced; Tesla quotes as much as a 5 times reduction compared to previous designs. This is due to the fact that electrons can now move directly towards the battery terminal, rather then having to take a more roundabout path to the center of the sheet first to reach the single-tab connection.
The end result is the 4680 cell, named for its 46 mm diameter and 80 mm length. This is a departure from the five-digit nomenclature, but nobody at Tesla could figure out why 18650 cells have the trailing zero, so the company eliminated it in the new cell's designation. The new cells are claimed to contain 5 times the energy earlier designs due to their larger size. Even better, Tesla claim they can deliver up to 6 times the power, due to the reduced electrical path length of tabless construction enabling better thermal performance. Estimates are that the switch to 4680 cells in Tesla's automotive packs could result in a range gain of as much as 16% — an impressive number given the automaker's already impressive numbers in this area. For example, the upcoming Model S Plaid claims to have a range of 520 miles using the 4680 cells.
The new 4680 cell from Tesla. It follows the naming scheme of the 18650, except dropping the trailing zero as nobody at the company could determine what it meant.
The new design brings production benefits, too. By laser-patterning the anode and cathode for direct connection, rather than attaching separate tabs, the materials can be handled through continuous roll processing, not dissimilar from techniques in paper production. This promises huge gains in production speed, with machinery able to move at continuous high speeds rather then having to continually accelerate and decelerate for tab attachment to each anode and cathode sheet. Tesla's goals to produce more batteries to meet demand are not practically achievable with current production techniques, so improvements in processing and production speed are key to solving this problem. This will also lead to reductions in cost, which is a major part of the company's effort to produce a more accessible electric vehicle at the $25,000 price point.
These new cells, with their greater energy density and high power output, would appeal to a huge market of hackers and makers. However, the continual theme throughout Tesla's keynote was that they simply can't source enough batteries to meet their needs as it is. We suspect that it will be several years before tabless batteries hit the open market, as Tesla keeps its entire supply for its own internal use. Other manufacturers will likely scramble to develop similar technology due to the gains on offer, but this will take time, and in the meantime, individuals wanting the best cylindrical cells will have to wait for new Teslas to show up in their local wrecking yards.
The tabless technology announcement was just one piece of Tesla's Battery Day announcements. Work is ongoing to make gains in other areas, such as anode and cathode chemistry, and production techniques, in order to meet the company's lofty goals of increased battery production to meet worldwide demand. If electric transportation and Powerwall grid storage are to truly change the world, projects like these will have to pay off — otherwise we simply won't have the batteries to put in the cars!
104 thoughts on "Tesla's New Tabless Batteries Unlock New Levels Of Performance
 1. There is an y axis. It is labeled "Supercharge time increase" and has one tick ("0") on it. And some very faint horizontal lines that hint that (but do not confirm) we are looking at a linear and not a logarithmic scale…
 1. Yes the wider tab (tabless ;) will help with heat in two ways… firstly there will be less heat generated via resistance in the jelly roll as the electrons only need to traverse ~40mm to the tabbed end rather than ~600mm on the larger roll format given a centre tapped jelly roll. Secondly the copper bottom and presumably similar aluminium top conductors will act as a rapid heat pipe out of the battery; aluminium and copper also having excellent thermal conductivity. The thermals will be so great that the efficiency of the battery pack will be improved while the cooling requirements will be significantly reduced.
 2. From what I understand, the cells shouldn't get as hot during charge and discharge due to the lower resistance (since the electrons don't have to travel as far). Heat is a limiting factor of charging and discharging (ignition is bad) so it will decrease the time required for both while retaining a similar thermal output.
 1. The change in current flow direction seems almost too obvious. Was there a seperate innovation which enabled this construction method, or is it just a case of nobody trying it before?
 2. The funny thing with having a "wide tab" like this is that it honestly is nothing new at all, and has existed on the market for a rather long time.
 And this is true for both capacitors and batteries alike.
 Though, there is honestly little reason to go with a continuous tab like this, going from the traditional single tab to one at either end more than doubles the cells performance, without making a headache out of folding the tabs into a package. But having more than two is of course still advantageous.
 But I am curious to if a nearly continues one is actually advantageous, or if it only add more copper bulk at either end than what it adds in performance. Diminishing returns is after all a thing. And if it only adds weight, and lowers density, then it isn't really a worth while thing to "waste" copper on…
 Ie, in the end, how often should one have tabs, and how wide should they be for optimal perfomrance?


Haven House offers specialist palliative care to life-limited children and young people who have a wide range of conditions.
There are a wide range of life-limiting and life-threatening conditions affecting children and young people, which can be categorised broadly into four groups.
Diagnosis is only part of the process of identifying children who need support from palliative care services: the spectrum and severity of the disease as well as the needs/wishes of and impact on the child and family also need to be taken into account.
The four categories can be defined as follows:
 1. Life-threatening conditions for which curative treatment may be feasible but can fail
 Access to palliative care services may be necessary when treatment fails or during an acute crisis, irrespective of the duration of threat to life. On reaching long-term remission or following successful curative treatment there is no longer a need for palliative care services.
 2. Conditions where premature death is inevitableThere may be long periods of intensive treatment aimed at prolonging life and allowing participation in normal activities. Examples: cystic fibrosis, duchenne muscular dystrophy.
 3. Progressive conditions without curative treatment optionsTreatment is exclusively palliative and may commonly extend over many years. Examples: batten disease, mucopolysaccharidoses.
 4. Irreversible but non-progressive conditions causing severe disability, leading to susceptibility to health
 Examples: severe cerebral palsy, multiple disabilities, such as following brain or spinal cord injury.
 Reference: Together for Short Lives ACT Criteria
Anyone can refer a child to Haven House, please read our Refer a Child section for more information


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Six Life Stages in the Life of a Cat
The Feline Advisory Bureau has identified six stages in a cat's life. Whilst each cat is unique, at certain stages of their lives, cats can be prone to certain health problems. Find out below what life stage your cat is in, what to be aware of and what you can do to ensure your cat lives a long and healthy life.
KITTEN – Birth to 6 months
- Check for conditions which may have been present since birth eg cleft palate.
- Agree diet, identification (eg microchipping) and discuss any behavioural issues.
- Kittens can be neutered from 4 months old.
JUNIOR – 7 months to 2 years
- Common health problems at this stage:
- Infectious diseases
- Problems related to hunting, fighting and trauma
- Can develop certain life-threatening conditions such as heart disease
- Priority is your cat's first vaccination booster and this should continue annually to maintain immunity
- After neutering, cats can put on weight – ask your veterinary team for advice on the correct weight for your cat and how to maintain that weight
PRIME – 3 years to 6 years
- Conditions that can arise include obesity, dental disease, cystitis, intestinal diseases, heart disease and behavioural problems. Regular healthchecks at the vets are very important.
- Parasite control very important especially as most cats this age are still keen hunters.
MATURE – 7 years to 10 years
- Increased risk of "older cat" conditions such as diabetes, kidney disease, high blood pressure, hyperthyroidism and cancer. Close monitoring by you and regular checkups at the vets are important. Signs to look out for include change in thirst, weight loss, vomiting, poor coat condition, diarrhoea.
- Obesity can also be a major problem in cats between 6 and 8 years old.
- Obesity can lead to many of the more serious conditions such as diabetes.
SENIOR – 11 years to 14 years
- More likely to suffer from the conditions described under the Mature stage.
- All these conditions are treatable so don't put it down to "old age" and let your cat suffer in silence.
- More likely to suffer from arthritis – for which treatment is available - and can also suffer from the equivalent of senile dementia.
GERIATRIC – 15 years +
- It is an achievement for a cat to reach this life stage!
- Cats of this age need to be monitored and check more regularly for all of the conditions referred to in the Mature and Senior life stages. Even at this age, your cat is still eligible for the treatment now available for all the conditions referred to.
For more information about the life stages of cats and plenty more "cat" information, visit _URL_.


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The Computing at School Working Group is an informal group that aims to promote the teaching of computing at school. Our membership is broad, and includes teachers, examiners, parents, university faculty, and employers.
CAS was born out of our excitement with our discipline, combined with a serious concern that our brightest students are being turned off computing by a combination of factors that have conspired to make the subject seem dull and pedestrian. Our goal is to put the fun back into computing at school.
They have a conference and regional support groups called hubs. So if you are a pre-collegiate computer science teacher or a university faculty/lecturer with an interest in helping support such education in the United Kingdom you will want to look into this program.
In the US there is still the Computer Science Teachers Association which, while is largest in the US, is really international in scope and membership.
Speaking of the CSTA, they just released the draft of a model curriculum (Level I Course: Foundations of Computer Science) that covers K-8 computer science. They are looking for comments and opinions on it so take a look.