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Cayuga-Seneca Canal

The Cayuga-Seneca Canal is a canal in New York, USA. It is now part of the New York State Canal System.

The Cayuga-Seneca Canal connects the Erie Canal to Cayuga Lake and Seneca Lake. It is approximately 20 miles long.


History

The Seneca River, now the Cayuga-Seneca Canal, always has been an economic engine for the communities of Waterloo and Seneca Falls. The Seneca Lock Navigation Co., a private enterprise formed in 1813, dammed three sets of rapids and installed locks to allow goods to be transported to the Erie Canal. In 1818, a canal was opened between Cayuga and Seneca Lakes. By 1823, an average of eight boats a day were passing through the lock at Waterloo, carrying flour, potash, pork, whiskey, lumber and wool and returning with other products and merchandise. Job Smith, Seneca Falls’ first businessman, opened a portage company on the eastern end of the river in 1787. The company transported travelers, boats and goods around a mile-long series
of rapids with a 2-foot drop known as “the Falls.”

The locks at Seneca Falls were completed in 1818. Improvements between the lakes, completed in 1821, made eight stone locks and nearly two miles of dug canal in addition to sections of the river. To further develop industry, the rapids were dammed to form the Upper, Middle and Lower Falls, and rapid industrialization began in 1825. Through Seneca Falls, there was a lock for every important mill site, raising or lowering the boats a total of 42 feet.

In 1825, a canal was begun to connect Seneca Lake with the newly constructed Erie Canal at Montezuma and the Cayuga-Seneca Canal was put into use in 1828. The Canal was enlarged in 1862, and the Flats, an area adjacent to and east of the village center, grew into a major industrial area, producing fire engines, hose carts and other firefighting equipment, pumps and other iron goods including stove parts, bootjacks, corn shellers, meat choppers, sausage stuffers, flatirons and bells. A knitting mill made socks and once produced 85,000 pairs of socks for the Army and Navy.

C-S Canal locks were modified in 1918 when New York State created the New York Barge Canal System. State engineers replaced five locks with a large two-flight lock - a 49 foot lift that required a great pool of water for their operation. This spelled the demise of the Flats. Buildings were destroyed or moved to create Van Cleef Lake. Flooding was completed on August 20, 1915.


Locks

The following list of locks are provided for the current canal, from east to west:

Lock # Location Lift
CS1 Cayuga n/a
CS2 Seneca Falls n/a
CS3 Seneca Falls n/a
CS4 Waterloo n/a


External Links

  • Information and Boater’s Guide to the New York State Canal System
  • New York State Canals


References

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Chubb Locks

The Chubb Locks subsidiary of the Assa Abloy Group is a British manufacturer of high security locking systems for residential and commercial applications.

Chubb was started as a ship’s ironmonger by Charles Chubb in Winchester, England and then moved to Portsmouth, England in 1804.

Chubb moved the company into the locksmith business in 1818 in Wolverhampton. The company worked out of a number of premises in Wolverhampton including the purpose built factory on Railway Street now still known as the Chubb Building. His brother Jeremiah Chubb then joined the company and they sold Jeremiah’s patented detector lock

In 1823 the company was awarded a special license by George IV and later became the sole supplier of locks to the General Post Office and a supplier to His Majesty’s Prison Service.

In 1835 they received a patent for a burglar-resisting safe and opened a safe factory in London in 1837.

In 1851 they designed a special secure display case for the Koh-i-Noor diamond for its appearance at the Great Exhibition.

In 1984 the company was purchased by Racal, who sold it in 1997 to Williams Plc. In August 2000, they were sold to Assa Abloy.


Cultural references

  • Chubb Locks is mentioned in Alan Hollinghurst’s 2005 novel, The Line of Beauty (in the very last pages).
  • Irene Adler’s manor in The Adventures of Sherlock Holmes is secured by a Chubb lock.


See also

  • Baron Hayter


External links

  • Official website

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Hilbert–Smith conjecture

In mathematics, the Hilbert-Smith conjecture is concerned with the transformation groups of manifolds; and in particular with the limitations on topological groups G that can act effectively (faithfully) on a (topological) manifold M. Restricting to G which are locally compact and have a continuous, faithful group action on M, it states that G must be a Lie group.

Because of known structural results on G, it is enough to deal with the case where G is the additive group Zp of p-adic integers, for some prime number p. An equivalent form of the conjecture is that Zp has no faithful group action on a topological manifold.

A proof of the conjecture was announced in 2002 by Louis McAuley, but it has not been accepted by the mathematical community. The conjecture is still widely considered to be open.

The naming of the conjecture is for David Hilbert, and the American topologist Paul A. Smith. It is considered by some to be a better formulation of Hilbert’s fifth problem, than the characterisation in the category of topological groups of the Lie groups often cited as a solution.

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Jinasena

Jinasena (जिनसेन) is the name of several famous Jain Acharyas of the Digambar tradition.

  • The author of Harivamsha Purana in the 8th century. He belonged to the Punnata branch of Jain monks.
  • The author of Mahapurana in the 9th century, he was the disciple of Virasena and he completed his teacher’s famous commentary “Dhavala” on Kashayaprabhrita. Mahapurana includes Adipurana and Uttarapurana, the project was completed by his pupil Gunabhadra.
  • The legendary founder of the Khandelwal Jain community.
  • Jinasena is also the traditional name of the Bhattarakas of the Sena Gana seat.

Mahapurana is the source of the famous quote:

Some foolish men declare that Creator made the world. The doctrine that the world was created is ill-advised, and should be rejected. If god created the world, where was he before creation? If you say he was transcendent then, and needed no support, where is he now?

No single being had the skill to make the world - for how can an immaterial god create that which is material? How could god have made the world without any raw material? If you say he made this first, and then the world, you are face with an endless regression. If you declare that the raw material arose naturally you fall into another fallacy, for the whole universe might thus have been its own creator, and have risen equally naturally. If god created the world by an act of will, without any raw material, then it is just his will made nothing else and who will believe this silly stuff?

If he is ever perfect, and complete, how could the will to create have arisen in him? If, on the other hand, he is not perfect, he could no more create the universe than a potter could. If he is formless, actionless, and all-embracing, how could he have created the world? Such a soul, devoid of all modality, would have no desire to create anything. If you say that he created to no purpose, because it was his nature to do so then god is pointless.

If he created in some kind of sport, it was the sport of a foolish child, leading to trouble. If he created out of love for living things and need of them he made the world; why did he not make creation wholly blissful, free from misfortune? Thus the doctrine that the world was created by god makes no sense at all.

[from Barbara Sproul, Primal Myths (San Francisco; Harper Row, 1979].

Mahapurana was the model for Saiva Siddhanta Periyapuranam which gives biographies of 63 individuals. Jinasena belonged to the Panchastupanvaya lineage of Jain monks. The spiritual lineage of Jinasena continues today and is called Senagana.


References

Anne E. Monius, “Love, Violence, and the Aesthetics of disgust: Saivas and Jains In Medieval South India”, Journal of Indian Philosophy, 2004, vol. 32, no 2-3, pp. 113 - 172

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Fetch-and-add

In computer science, the fetch-and-add CPU instruction is a special instruction that atomically modifies the contents of a memory location. It is used to implement Mutual exclusion and concurrent algorithms in multiprocessor systems.

In uniprocessor systems, it is sufficient to disable interrupts before accessing a critical region.
However, in multiprocessor systems, it is impossible and undesirable to disable interrupts on all processors at the same time; and even with interrupts disabled two or more processors could be attempting to access the same memory at the same time. The fetch-and-add instruction, allows any processor to atomically increment a value in memory location, preventing such multiple processor collisions.

Maurice Herlihy (1993) proved that fetch-and-add is inferior to compare-and-swap.


Implementation

The standard fetch and add -instruction behaves like the following function. Crucially the entire function is executed atomically: no process can interrupt the function mid-execution and hence see a state that only exists during the execution of the function. This code only serves to help explain the behaviour of fetch-and-add; atomicity requires explicit hardware support and hence can not be implemented as a simple high level function. 

<< atomic >>
function FetchAndAdd(address location) {
    int value := *location
    *location := value + 1
    return value
}

With fetch-and-add primitive a mutual exclusion lock can be implemented as: 

 record locktype {
    int ticketnumber
    int turn
 }
 procedure LockInit( locktype* lock ) {
    lock.ticketnumber := 0
    lock.turn  := 0
 }
 procedure Lock( locktype* lock ) {
    int myturn := FetchAndAdd( &lock.ticketnumber )
    while lock.turn ≠ myturn
        skip // spin until lock is acquired
 }
 procedure UnLock( locktype* lock) {
    FetchAndAdd( &lock.turn )
 }

These routines provide a mutual-exclusion lock when following conditions are met:

  • Locktype data structure is initialized with function LockInit before use
  • Number of tasks waiting for the lock does not exceed INT_MAX at any time
  • Integer datatype used in lock values can ‘wrap around’ when continuously incremented


x86 implementation

In the x86 architecture, the instruction ADD with the first operand specifying a memory location is a fetch-and-add instruction that has been there since the 8086 (it just wasn’t called that then), and with the LOCK prefix, is atomic across multiple processors. However, it could not return the original value of the memory location (though it returned some flags) until the 486 introduced the XADD instruction.


See also

  • Test-and-set
  • Test and Test-and-set
  • Compare-and-swap
  • Load-Link/Store-Conditional

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Fulton Lock

The Fulton Lock (formerly named Lock C) is part of the Tennessee-Tombigbee Waterway. It is located close to Fulton, Mississippi.

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Conservative two-phase locking

In computer science, conservative two-phase locking (C2PL) is a locking method used in DBMS and relational databases.

Conservative 2PL prevents deadlocks.

The difference between 2PL and C2PL is that C2PL’s transactions obtain all the locks they need before the transactions begin. This is to ensure that a transaction that already holds some locks will not block waiting for other locks.

In heavy lock contention, C2PL reduces the time locks are held on average, relative to 2PL and Strict 2PL, because transactions that hold locks are never blocked.

In light lock contention, C2PL holds more locks than is necessary, because it is hard to tell what locks will be needed in the future, thus leads to higher overhead.

Also, a transaction will not even obtain any locks if it cannot obtain all the locks it needs in its initial request. Furthermore, each transaction needs to declare its read and write set (data items to be read/written during transaction), which is not always possible. Because of these limitations, C2PL is not used very frequently.

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Distributed Transaction Coordinator

The Distributed Transaction Coordinator (MSDTC) service is a component of modern versions of Microsoft Windows that is responsible for coordinating transactions that span multiple resource managers, such as databases, message queues, and file systems. MSDTC is included in Windows 2000 and later operating systems, and is also available for Windows NT 4.0.

MSDTC performs the transaction coordination role for components, usually with COM and .NET architectures. In MSDTC terminology, the director is called the transaction manager.


See also

  • List of Microsoft Windows components
  • Kernel Transaction Manager
  • Windows Vista I/O technologies


External links

  • Distributed Transaction Coordinator on the Microsoft Developer Network
  • New functionality in the Distributed Transaction Coordinator service in Windows Server 2003 Service Pack 1 and in Windows XP Service Pack 2
  • Florin Lazar’s weblog; a Microsoft developer blog with extensive discussions on MSDTC and transaction processing

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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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Bingley Three Rise Locks

Bingley Three Rise Locks is a staircase of three locks on the Leeds and Liverpool Canal at Bingley. It opened in 1774 and was a major feat of engineering at the time along with the larger Five Rise (more details on construction and history here) opened at the same time just a few hundred meters further up. The lock comprises a ’staircase’ flight - the lower gate of one lock forms the upper gate of the next lock.


External links

  • Pennine Waterways

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Tubular lock pick

A tubular lock pick is a specialized lockpicking tool used for opening a tubular pin tumbler lock. Tubular lock picks are all very similar in design and come in sizes to fit all major tubular locks, including 6, 7, and 8-pin locks.

The tool is simply inserted into the lock and turned clockwise with medium tension. As the tool is pushed into the lock, each of the picks is slowly forced down until they stop, thus binding the driver pins behind the shear line of the lock. When the final pick is pushed down, the shear plane is clear and the lock opens. This can usually be accomplished in a matter of seconds.

Most tubular lock picks come with a “decoder” which lets the locksmith know at what depths the pins broke the shear plane. By using the decoding key after the lock has been picked, the locksmith can cut a tubular key to the correct pin depths and thus avoid having to replace the lock.

In 2004 it was widely publicized that the barrel of a cheap ballpoint pen would act as an effective lock pick for many brands of tubular lock.


External links

  • Large picture of a Southord tubular lock pick
  • Tubular lock picks for sale on froogle
  • Devonlocks.com’s guide to using a Southord tubular lock pick

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Prescient store

A prescient store is an operation to allow store operations to occur earlier than would otherwise be permitted in the context of threads and locks. The process needs some way of knowing ahead of time what value will be stored by the assignment that it should have followed. The purpose of this relaxation is to allow compiler optimization to perform certain kinds of code rearrangement that preserve the semantics of properly synchronized programs.

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David Lock

David Anthony Lock (born 2 May 1960) is a politician in the United Kingdom. He was elected Labour Member of Parliament for Wyre Forest in the 1997 general election, but lost his seat in the 2001 election to Richard Taylor, the Independent Kidderminster Hospital and Health Concern candidate.

He became the first Labour MP in the Wyre Forest for many years but dramatically lost popularity with his subdued support for the reduction in services at Kidderminster Hospital in the late 1990s.

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Disclaimer (patent)

In patent law, a disclaimer is an amendment consisting in limiting a claim of a patent or patent application by introducing a negative technical feature. It typically consists in excluding from a general feature specific embodiments or areas. During prosecution, such amendments are sometimes made by applicants to their application, with the hope of fulfilling some patentability criteria, such as the novelty criterion.

The allowability of disclaimers is usually subject to certain conditions, which may vary from one country to another.


European Patent Office (EPO)

Under the case law of the Boards of Appeal of the EPO, disclaimers are allowed only in certain circumstances, as confirmed in G 1/03 and G 2/03 decisions.

“A disclaimer [which is not disclosed in the description] may be allowable in order to:

  • restore novelty by delimiting a claim against state of the art under ;
  • restore novelty by delimiting a claim against an accidental anticipation under ; an anticipation is accidental if it is so unrelated to and remote from the claimed invention that the person skilled in the art would never have taken it into consideration when making the invention; and
  • disclaim subject-matter which, under Articles 52 to 57 EPC, is excluded from patentability for non-technical reasons.” [1]


References

  • Guidelines for Examination in the EPO, Part C

    • Chapter III, 4.12. Negative limitations (e.g. disclaimers) [2]
    • Chapter VI, 5.3.11. Disclaimers not disclosed in the application as filed [3]
  • Patentability of Negative Limitations at the USPTO [4]


See also

  • Proviso (patent)

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Forum Building

The Forum Building, designed by the Swiss architects Jaques Herzog and Pierre de Meuron (Herzog & de Meuron), is considered by some to be an icon of the “New Barcelona”.

It is a triangular building measuring 180 meters on each side and 25 meters in height, located within the triangle formed by Diagonal Avenue, Rambla de Prim and the Ronda Litoral.

It was the symbol of the controversial 2004 Universal Forum of Cultures and the serious flaws that arose during its construction were widely covered in both the Spanish national and foreign press <ref>Architectural Flaws, The Guardian.</ref>. The edifice has become a political bone of contention, with the opposition parties in both Barcelona Council and the Parliament of Catalonia demanding to know why it cost so much (of the order of US $144 m).

The building has an auditorium with a seating capacity of 3,200 and an exhibition hall covering nearly 5,000 square meters.


See also

  • Herzog & de Meuron
  • 2004 Universal Forum of Cultures


References


External links

  • Photos of Forum Building

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Strict function

A strict function in the denotational semantics of programming languages is a function f where <math>f\left(\perp\right) = \perp</math>. The entity <math>\perp</math>, called “bottom”, denotes an expression which does not return a normal value, either because it loops endlessly or because it aborts due to an error such as division by zero. A function which is not strict is called non-strict. A strict programming language is one in which user-defined functions are always strict.

Intuitively, non-strict functions correspond to control structures. Operationally, a strict function is one which always evaluates its argument, a non-strict function is one which may not evaluate some of its arguments. Functions having more than one parameter may be strict or non-strict in each parameter independently, as well as jointly strict in several parameters simultaneously.

As an example, the if-then-else expression of many programming languages may be thought of as a function of three parameters. This function is strict in its first parameter, since the function must know whether its first argument evaluates to true or to false before it can return; but it is non-strict in its second parameter, because (for example) if(false,<math>\perp</math>,1) = 1, as well as non-strict in its third parameter, because (for example) if(true,2,<math>\perp</math>) = 2. However, it is jointly strict in its second and third parameters, since if(true,<math>\perp</math>,<math>\perp</math>) = <math>\perp</math> and if(false,<math>\perp</math>,<math>\perp</math>) = <math>\perp</math>.


See also

  • Strictness analysis

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Interjurisdictional immunity

In Canadian Constitutional law, interjurisdictional immunity is the legal doctrine that prevents a law from being applied to matters outside of the constitutional jurisdiction of the enacting head of power. For example, where a provincial law is found to intrude into a matter in the jurisdiction of the federal government the law will be interpreted through the “reading down” doctrine to exclude that matter. The immmunity doctrine is invoked when it is found that the legislation “affects a vital or essential part” of a matter outside the government’s jurisdiction.

Though there remains some debate, it has generally been accepted that the doctrine applies to both the federal and provincial governments equally. Nevertheless, virtually all of the case law concerns situations where provincial laws encroach on federal matters.

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Small joint manipulation

For the medical procedure, see Joint manipulation

Small joint manipulation refers to twisting, pulling or bending fingers or toes to cause joint locks in the various joints in those appendages. Joint locks on fingers and toes are respectively referred to as finger locks and toe locks.


Explanation

The leverage needed for such joint manipulation is comparatively small, since grabbing a finger or two with one or both hands creates a distinct advantage, and means that a weaker person can possibly control a stronger one. Grabbing only one finger may lead to the opponent being able to pull it free, while grabbing three or more reduces the leverage advantage considerably, and hence it is sometimes advised to grab two fingers for maximum effect.

Small joint manipulation is an illegal technique in most combat sports that feature joint locking such as Brazilian Jiu-Jitsu, Judo, Mixed Martial Arts and Sambo, since unlike standard joint locks, there is less of an opportunity to tap out before the small joint breaks. It is however sometimes taught as a self-defense and pain compliance technique, for instance in Kenpo, Jujutsu, and especially in ‘Small Circle JuJitsu’. It is also an important part of koppo-techniques, e.g. in ninjutsu.


See also

  • Armlock
  • Leglock
  • Spinal lock
  • Wristlock


References

  • Modern Kempo Martial arts. Small Circle Jujitsu. www.modernkempo.com. URL last accessed March 6 2006.
  • Yoshin Ryu Ju-jitsuYoshin Ryu Ju-jitsu Instruction. www.angelfire.com. URL last accessed March 6 2006.
  • Zine.infinitemma.com. MMA Terms. zine.infinitemma.com. URL last accessed March 6 2006.