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Nationalist Liberal

Nationalist Liberal was the label under which Fleming Blanchard McCurdy ran in a by-election held in Colchester, Nova Scotia, Canada, on September 20, 1920.

McCurdy had been a Conservative Member of Parliament since 1911 and, as all Conservatives, became a Unionist in 1917, serving as Parliamentary Secretary to Sir Robert Borden.

Prime Minister Arthur Meighen appointed McCurdy to his Cabinet as Minister of Public Works in July 1920. At that time, new Cabinet appointees were required to seek re-election in a by-election. It is unknown why McCurdy ran as a Nationalist Liberal, but it may have had something to do with the fact that the Conservative/Unionist Party had changed its formal name to the National Liberal and Conservative Party or because his sole challenger was a member of the newly formed, left-wing United Farmers. McCurdy won the 1920 by-election by a narrow margin. He reverted to the Conservative label in 1921 and was defeated.

  • See also: List of political parties in Canada

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Mortise lock

Created by Eli Whitney’s ( creator of the cotton gin ) nephews, Eli Whitney and Philos Blake, a mortise lock (also mortice lock in British English) is one that requires a pocket - the mortise - to be cut into the door or piece of furniture into which the lock is to be fitted. In most parts of the world, mortise locks are generally found on older buildings constructed before the advent of bored cylindrical locks, but they have recently become more common in commercial and upmarket residential construction in the United States.

The parts included in the typical mortise lock installation are the lock body (the part installed inside the mortise cut-out in the door); the lock trim (which may be selected from any number of designs of doorknobs, levers, handle sets and pulls); a strike plate, or a box keep, which lines the hole in the frame into which the bolt fits; and the keyed mortise cylinder which operates the locking/unlocking function of the lock body. However, in the United Kingdom, and certain other countries, most mortise locks on dwellings do not use cylinders, but have lever tumbler mechanisms.

The installation of a mortise lock cannot generally be undertaken by the average homeowner since it is labor intensive and requires a working knowledge of basic woodworking tools and methods. Many installation specialists use a mortising jig which makes precise cutting of the pocket a simple operation, but the subsequent installation of the external trim can still prove problematic if the installer is inexperienced.

Although the installation of a mortise lock actually weakens the structure of the typical timber door, a mortise lock does offer more versatility than a bored cylindrical lock, both in external trim, and functionality. Whereas the latter mechanism lacks the architecture required for ornate and solid-cast knobs and levers, the mortise lock can accommodate a heavier return spring and a more solid internal mechanism, making their use possible. Furthermore, a mortise lock will typically accept a wide range of other manufacturers’ cylinders and accessories, allowing architectural conformity with lock hardware already on site.

Some of the most common manufacturers of mortise locks in the United States are Baldwin, Best, Corbin Russwin, Emtek, Falcon, Schlage, and Sargent. Also, many European manufacturers whose products had been restricted to “designer” installations have recently gained wider acceptance and use.

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Absolute deviation

In statistics, the absolute deviation of an element of a data set is the absolute difference between that element and a given point. Typically the point from which the deviation is measured is the value of either the median or the mean of the data set.

<math>|D| = |x_i-\overline{x}| </math>

where

|D| is the absolute deviation,
xi is the data element
and <math>\overline{x}</math> is the chosen measure of central tendency of the data set.

The average absolute deviation (or simply average deviation) of a data set is the average (or expected value) of the absolute deviations and is a summary statistic of statistical dispersion or variability.

The average absolute deviation of a set {x1, x2, …, xn} is

<math>\frac{1}{n}\sum_{i=1}^n |x_i-\overline{x}|</math>

The choice of measure of central tendency has a marked effect on the value of the average deviation. For example, for the data set {2, 2, 3, 4, 14}:

Measure of central tendency Absolute deviation
Mean = 5 2 - 5| + |2 - 5| + |3 - 5| + |4 - 5| + |14 - 5|}{5} = 3.6</MATH>
Median = 3 2 - 3| + |2 - 3| + |3 - 3| + |4 - 3| + |14 - 3|}{5} = 2.8</MATH>
Mode = 2 2 - 2| + |2 - 2| + |3 - 2| + |4 - 2| + |14 - 2|}{5} = 3.0</MATH>

The average absolute deviation from the median is less than or equal to the average absolute deviation from the mean. In fact, the average absolute deviation from the median is always less than or equal to the average absolute deviation from any other fixed number.

The average absolute deviation from the mean is less than or equal to the standard deviation. One way of proving that relies on Jensen’s inequality.

The mean absolute deviation is the average absolute deviation from the mean and is a common measure of forecast error in time series analysis. It should be noted that although the term mean deviation is used as a synonym for mean absolute deviation, to be precise it is not the same; in its strict interpretation (namely, omitting the absolute value operation), the mean deviation of any data set from its mean is always zero.

The mean absolute deviation of a sample is a biased estimator of the mean absolute deviation of the population.


See also

  • Deviation (statistics)
  • Median absolute deviation


External links

  • Advantages of the mean absolute deviation

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Pin tumbler lock

The pin tumbler lock is a lock mechanism that uses pins of varying lengths to prevent the lock from opening without the correct key. Pin tumblers are most commonly employed in cylinder locks, but may also be found in tubular or radial locks.


History

The basic principles of the pin tumbler lock may date as far back as 2000 BC in Egypt; the lock consisted of a wooden post affixed to the door, and a horizontal bolt that slid into the post. The bolt had vertical openings into which fitted a set of pins. These could be lifted, using a key, to a sufficient height to allow the bolt to move and unlock the door.

Inventor Linus Yale, Sr. patented a cylindrical pin tumbler lock in 1848, a design which was further improved and patented by his son, Linus Yale, Jr., in 1861. Yale, Jr.’s design is very similar to pin tumbler locks manufactured today.


Design

The pin tumbler is commonly used in cylinder locks. In this type of lock, an outer casing has a cylindrical hole in which the plug is housed. To open the lock, the plug must rotate.

The plug has a straight-shaped slot known as the keyway at one end to allow the key to enter the plug; the other end may have a cam or lever which activates a mechanism to retract a locking bolt. The keyway often has protruding ledges which serve to prevent the key pins from falling into the plug, and to make the lock more resistant to picking. A series of holes, typically five or six of them, are drilled vertically into the plug. These holes contain key pins of various lengths, which are rounded to permit the key to slide over them easily.

Above each key pin is a corresponding set of driver pins, which are spring-loaded. Simpler locks typically have only one driver pin for each key pin, but locks requiring multi-keyed entry, such as a group of locks having a master key, may have extra driver pins known as spacer pins. The outer casing has several vertical shafts, which hold the spring-loaded pins.

When the plug and outer casing are assembled, the pins are pushed down into the plug by the springs. The point where the plug and cylinder meet is called the shear point. With a key properly cut and inserted into the groove on the end of the plug, the pins will rise causing them to align exactly at the shear point. This allows the plug to rotate, thus opening the lock. When the key is not in the lock, the pins straddle the shear point, preventing the plug from rotating. Sets of locks with a master key will have one set of shear points that are identical to the others in the set and one set that is unique to that specific lock.


See also

  • Tubular pin tumbler lock
  • Lock bumping
  • Lock picking


Patent

  • — Lock
  • — Lock
  • — Lock and key


External links

  • The pin tumbler invention at Yale company site
  • Locking It Up with a Pin Tumbler Lock

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Windsor Locks, Connecticut Tornado

The Windsor Locks, Connecticut tornado struck on October 3 1979. The short-lived, but intense F4 tornado (see Fujita scale) caused 3 deaths, 500 injuries, and - with more than $300 million in property damage along an 11-mile path - ranks as one of the most expensively destructive tornadoes in American history.

The tornado touched down in the town of Poquonock, Connecticut, just north of Hartford, Connecticut in the Connecticut River valley. It traveled north through the town of Windsor Locks, Connecticut before dissipating in the town of Suffield, Connecticut, just south of the Massachusetts state line.

The path of the tornado crossed the northern portion of Bradley International Airport, and many vintage aircraft at the nearby New England Air Museum were damaged or destroyed by the storm.


See also

  • List of tornadoes and tornado outbreaks
  • Fujita scale


External link

  • The Windsor Locks, Connecticut Tornado of 3 October 1979: An Analysis of an Intermittent Severe Weather Event

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Distributed database management system

A distributed database management system is a software system that permits the management of a distributed database and makes the distribution transparent to the users. A distributed database is a collection of multiple, logically interrelated databases distributed over a computer network. Sometimes “distributed database system” is used to refer jointly to the distributed database and the distributed DBMS.


References

  • M. T. Özsu and P. Valduriez, Principles of Distributed Database Systems (2nd edition), Prentice-Hall, 1999. ISBN 0-13-659707-6.

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Golden beryl

Golden beryl is one of the many hues of the “gemstone” mineral beryl. It can range in colors from pale yellow to a brilliant gold. Unlike emerald, golden beryl has very few flaws.

The term “golden beryl” is sometimes synonymous with heliodor, but in the strict sense, golden beryl refers to pure yellow or golden yellow shades, while heliodor refers to the greenish-yellow shades.

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5 Lever Lock

5 Lever Lock is a type of lock often required for home insurance. There are various ‘grades’ but the current British Standard is usually required for insurance purposes.
The lever mechanism is really only seen in the UK and some parts of Scandinavia, and locks using this form of mechanism are frequently referred to as ‘Chubb Locks’ although there are a great many manufacturs.


The Lever

A flat non ferrous metal shaped double acting movable ‘detainer’ in a lock. Usually pivoted, but sometimes slide. The levers in a lock have to be moved by the key to operate the lock. The belly of the lever is cut away to various depths to provide different combinations. A lever will have pockets and gates through which the bolt stump moves during unlocking

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Relative angular momentum

In astrodynamics, the relative angular momentum (<math>\mathbf{H_{{2}/{1}}}\,\!</math>) of an orbiting body (<math>m_2\,\!</math>) relative to a central body (<math>m_1\,\!</math>) is the moment of (<math>m_2\,\!</math>)’s relative linear momentum:

<math>\mathbf{H_{{2}/{1}}}=\mathbf{r}\times m_2\mathbf{v}\,\!</math>

where:

  • <math>\mathbf{r}\,\!</math> is the orbital position vector of the orbiting body relative to the central body,
  • <math>\mathbf{v}\,\!</math> is the orbital velocity vector of the orbiting body relative to the central body,
  • <math>m_2\,\!</math> is mass of the orbiting body.

For an body orbiting a central body <math>\mathbf{H_{{2}/{1}}}\,\!</math> is always perpendicular to the osculating orbital plane determined by orbital position and velocity vectors.


Uses

In astrodynamics relative angular momentum is usually used to derive specific relative angular momentum (<math>\mathbf{h}\,\!</math>):

<math>\mathbf{h}=\mathbf{H_{{2}/{1}}}/m_2\,\!</math>

where:

  • <math>m_2\,\!</math> is mass of the orbiting body.


See also

  • Specific relative angular momentum
  • Linear momentum
  • Momentum

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Connivance

A legal finding of connivance may be made when an accuser has assisted in the act about which they are complaining. In some legal jurisdictions, and for certain behaviors, it may prevent the accuser from prevailing.

For example, if someone were to entice their spouse to commit adultery, they might be blocked (or estopped) from divorcing their spouse on grounds of that adultery.


See also

  • Collusion

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Air lock

An air lock is gas trapped in a high point of a liquid-filled pipe system. The gas, being lighter than the liquid, rises to the highest point and restricts the flow of liquid. In very tall systems, the gas can prevent flow entirely.

Flushing the system with high flow or pressures can help move the gas away from the highest point, or a tap can be installed to permit the gas to be vented.


See also

  • fermentation lock, a brewing device
  • vapour lock, a gas bubble affecting fluid flow within a pipe

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Quad Data Rate SRAM

Quad Data Rate (QDR) SRAM is a type of static RAM computer memory that can transfer up to four words of data in each clock cycle. Like Double Data-Rate (DDR) SDRAM, QDR SRAM transfers data on both rising and falling edges of the clock signal. This requires more wires between the memory device and the memory controller, but doubles the theoretical maximum data transfer rate. QDR SRAM uses two clocks, one for read data and one for write data. This helps to eliminate problems caused by the propagation delay of the clock wiring, and allows concurrent reads and writes, thereby doubling the transfer rate again.

QDR SRAM is designed for high-speed communications and networking applications, where data throughput is more important than cost, power efficiency or density. The technology is a joint development by Cypress, Renesas, IDT, NEC, and Samsung.


I/O


Clock inputs

4 clock lines:

  • Input clock:

    • K
    • not-K, or /K
  • Output clock:
    • C
    • not-C, or /C


Control inputs

Two control lines:

  • not-Write enable: /WPS
  • not-Read enable: /RPS


Buses

One address bus and two data buses:

  • Address bus
  • Data in bus
  • Data out bus


Clocking scheme

  • Addresses

    • Read address latched on rising edge of K
    • Write address latched on rising edge of K
  • Data

    • Write

      • If /WPS is low

        • A data word on Data In is latched on rising edge of K
        • The next data word on Data In is latched on rising edge of /K
    • Read
      • A read is a two-cycle process
      • If /RPS is low
        • The first rising edge of K latches the read address, A
        • The second rising edge of K puts the data word, from address A, on the Data Out bus
        • The next rising edge of /K puts the next data word, from address A+1, on the Data Out bus


External Links

  • QDR SRAM home page
  • Quad Data Rate SRAM Clocking Scheme Cypress
  • Quad Data Rate Description Electronic design article

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James Petiver

James Petiver (1663-1718) was a London apothecary, a Fellow of the Royal Society as well as London’s informal Temple Coffee House Botany Club, famous for his study of botany and entomology. He named the Red Admiral butterfly after a British Naval Flag and named Fritillary after a chequered dice box.

Petiver received many plant specimens, seeds and much other material from correspondents in the American colonies.


Works

  • 1698 An account of some Indian plants etc. with their names, descriptions and vertues; communicated in a letter from Mr. James Petiver…to Mr. Samuel Brown, surgeon at Fort St. George, Philosophical Transactions of the Royal Society, London.
  • 1700-1703 - An account of part of a collection of curious plants and drugs, lately given to the Royal Society of the East India Company, Philosophical Transactions of the Royal Society


External Links

  • [1]–Digitised versions of Aquatilium Animalium Amboinæ, etc.;Gazophylacium naturae et artisand Pteri-Graphia Americana at GDZ Göttingen.


Collections

British Natural History Museum

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