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Stasis Lock

Stasis Lock is a coma-like state that Transformers fall into when their body is damaged, their Energon reserves are depleted, or they are exposed to too much Energon radiation. Stasis Lock’s purpose is to prevent further damage or power depletion from occurring. Stasis Lock itself is not fatal, but the only way to recover from stasis lock is to use a CR Chamber.
Stasis lock was first mentioned in “Beast Wars pt 1″ when Megatron’s computer told him that there was too much Raw Energon on Earth, and that it could damage him along with the other Predacons (as well as the Maximals) after prolonged exposure.

Under dire circumstances, it is possible for a transformer to overide stasis lock and continue to function. However, this is an extremely risky move since any additional damage or energy depletion can be fatal. An example of this occurs in “Code of Hero” where Dinobot overides stasis lock to battle Megatron, despite his internal computer’s objections. Although Dinobot continued functioning long enough to disable Megatron, his energy reserves dropped below the point where stasis lock could save him. He died shortly after the other Maximals arrived.

Readers-writer lock

In computer science, a readers-writer lock (also known by the name multi-reader lock, or by typographical variants such as readers/writers lock) is a synchronization primitive that solves one of the readers-writers problems. A readers-writer lock is like a mutex, in that it controls access to some shared memory area, but it allows multiple threads to read from the shared area concurrently. Any thread that needs to write to the shared memory, of course, needs to acquire an exclusive lock.

Readers-writer locks are usually constructed on top of mutexes and condition variables, or on top of semaphores. They are rarely implemented from scratch.

Coffin lock

Coffin Lock is a slang term for a blind panel connector (also called a Butt-Joint Fastener) often used in performing arts to join together stage decks or scenery in a butt joint or cabinet and lid locks on road cases. These are typically two part connectors (male and female) that draw together and lock. The two most common types are the cam and acceptor (sold under the trade name “Roto-Lock”) and more traditional hook and pin version. These devices generally use an Allen key to operate the locking mechanism via a small diameter hole either through the face or rear of the panel. When locked, the considerable mechanical advantage offered by the cam or hook holds the panels tightly together. Coffin locks can be installed directly into a mortise cut into each panel, for total concealment except for the locking hole, or mounted to the rear of the panels.

Göta Canal

The Göta Canal () is a Swedish canal constructed in the early 19th century. The canal stretche from Gothenburg on the west coast, combined with the river Göta älv and the Trollhätte canal, through the large lakes Vänern and Vättern, in parallel with Motala ström, and to Söderköping on the Baltic Sea.

The architect was Baltzar von Platen, working to plans earlier developed at the request of the Swedish king by the Scottish civil engineer Thomas Telford; he got permission to begin to work on April 11, 1810 and the canal was officially opened on September 26, 1832. Telford himself travelled to Sweden in 1810 to oversee some of the initial excavations on the project.

Built only decades before the advent of railways, the canal was soon outdated, and never upgraded. The canal is a tourist attraction, sometimes called Sveriges blå band (”Sweden’s Blue Ribbon”).

To support the building of the canal with mechanical works, a small engineering workshop was established in Motala called Motala Verkstad. This industry has sometimes been referred to as cradle of the Swedish engineering industry.


In fiction

Several movies depict the canal, most notably the 1981 comedy Göta Kanal, in which two competing yacht constructors race the canal in order to win a huge construction stock order. In 2006, Göta Kanal 2 was released.


Locks

From the east-coast of Sweden all the way to the west-coast the locks are as follows:
(with meters per locks)

  • Mem, 3
  • Tegelbruket, 2.3
  • Söderköping, 2.4
  • Duvkullen nedre, 2.3
  • Duvkullen övre, 2.4
  • Mariehov nedre, 2.1
  • Mariehov övre, 2.6
  • Carlsborg nedre, 5.1
  • Carlsborg övre, 4.7
  • Klämman, open
  • Hulta, 3.2
  • Bråttom, 2.3
  • Norsholm, 0.8
  • Carl Johans slussar (seven locks), 18.8
  • Oskars slussar, 4.8
  • Karl Ludvig Eugéns slussar, 5.5
  • Brunnby, 5.3
  • Heda, 5.2
  • Borensberg, 0.2
  • Borenshult, 15.3
  • Motala, 0.1

Lake Vättern

  • Forsvik, 3.5
  • Tåtorp, 0.2
  • Hajstorp övre, 5.0
  • Hajstorp nedre, 5.1
  • Riksberg, 7.5
  • Godhögen, 5.1
  • Norrkvarn övre, 2.9
  • Norrkvarn nedre, 2.9
  • Sjötorp 7-8, 4.6
  • Sjötorp 6, 2.4
  • Sjötorp 4-5, 4.8
  • Sjötorp 2-3, 4.8
  • Sjötorp 1, 2.9


Photographs of the Göta Canal


Trivia

The canal is nicknamed “skilmässodiket” which translates to “divorce ditch”. The name refers to the stress endured by couples navigating the numerous locks in the canal.


See also

  • List of Swedish government enterprises


Bibliography

  • Eric de Maré, Swedish Cross Cut, Sweden, 1965. (In English)


External links

  • Göta Canal - Official site

Pleochroism

Pleochroism is an optical phenomenon in which grains of a rock appear to be different colors when observed at different angles,under a petrographic microscope.

Pleochorism is caused by the double refraction of light by a colored gem or crystal. Light of different polarizations is bent different amounts by the crystal, and therefore follows different paths through the crystal. The components of a divided light beam follow different paths within the stone and travel at different speeds, and each path will absorb different colors of light. When the stone is observed at some angle, light following some combination of paths and polarizations will be present, each of which will have had light of different colors absorbed. At another angle, the light passing through the stone will be composed of another combination of light paths and polarizations, each with their own color. The light passing through the stone will therefore have different colors when it is viewed from different angles, making the stone seem to be of different colors.

Some stones show two colors or shades and are called dichroic. Some show three and are trichroic. Gems are sometimes cut and set either to display pleochroism or to hide it, depending on the colors and their attractiveness.

Pleochroism is an extremely useful tool in mineralogy for mineral identification, since minerals that are otherwise very similar often have very different pleochroic color schemes. In such cases, a thin section of the mineral is used and examined under transmitted light in a microscope.


See also

  • Birefringence

Whitchurch Lock

Whitchurch Lock is a lock and weir situated on the River Thames in England. The lock is located in the Oxfordshire village of Whitchurch-on-Thames but the weir crosses the river to the Berkshire village of Pangbourne. Both lock and weir are owned and managed by the Environment Agency.

The long serving lock keeper is Brian Butcher who has worked on the river for more than forty years starting as an apprentice engineer for Bert Bushnell’s hire fleet based in Maidenhead in the 1960s.


Access to the lock

Whitchurch Lock is one of the few locks on the River Thames which has no public access other than by boat.


Reach above the lock

The reach passes along the Chiltern Hills, culminating in Goring Gap. On the Oxfordshire side are Hartslock beech woods, named after a lock that was removed in 1910. On the Berksire side is Child Beale Wildlife Park. The Thames Path crosses Whitchurch Bridge into Oxfordshire and continues through Whitchurch away from the river as it goes round Coombe Park, returning to the river at Hartslock. It continues on the Oxfordshire river bank to Goring.


See also

  • Locks on the River Thames

{{UK-canal-stub}

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Foxton Locks

Foxton Locks are ten canal locks consisting of two “staircases” each of five locks, located on the Leicester line of the Grand Union Canal about 5 km west of the Leicestershire town of Market Harborough and are named after the nearby village of Foxton.

They form the northern terminus of a 20-mile summit level that passes Husbands Bosworth, Crick and ends with the Watford flight

Staircase locks are used where a canal needs to climb a steep hill, and consist of groups of locks which open directly into each other. Foxton Locks are the largest flight of such staircase locks on the English canal system.

The Grade II* listed locks are a popular tourist attraction and the county council has created a country park at the top. At the bottom, where the junction with the arm to Market Harborough is located, there are two public houses, a shop, trip boat and other facilities. The area is thus ideal for gongoozlers.


The locks

Building work on the locks started in 1810 and was finished 4 years later in 1814. Little changed until the building of the inclined plane resulted in the reduction in size of some of the side pounds.While the inclined plane was in operation the locks were allowed to fall into decline to an extent and in 1908 the committee released £1000 to bring the locks back into full operation.

On the 26 November 2006 boaters blockaded the locks as part of protests against Defra cutting British Waterways funding.


Foxton Inclined Plane

In 1900 an inclined plane was built to the side of the locks. The aim was partly to speed up the passage of boats, but also as part of an effort to allow the passage of wide-beam barges instead of just narrowboats.

It was designed by Gordon Cale Thomas and had 2 tanks or caissons, each capable of holding 2 narrowboats or a barge. The caissons were full of water, and so balanced each other. The lift was powered by a 25 horsepower (19 kW) stationary engine. The land for the project was purchased for £1,595 and with the entire project costing £39,244 by 24 June 1900.

The inclined plane had a journey time of 12 minutes for 2 boats up and 2 down and improved the speed of passage up the hill tremendously. Unlike the locks, where water flowed downhill every time a boat passed through, on the inclined plane almost the same amount of water went up and down the hill. Only the displaced water is moved, thus saving a great deal of water and giving better control of this vital resource.

There was a plan to build a similar inclined plane at the Watford Locks at the southern end of the canal’s summit level. However, this was never carried through, and as the Watford Locks were never widened, the economic benefits of the plane could not be fully realised. Thus, despite its obvious effectiveness, the Foxton Inclined Plane was mothballed in 1911 to save money. After that date it saw occasional use when the locks were undergoing maintenance

In 1927, dismantling of the incline began, so that it could be sold for scrap. That year the chimney on the engine house was demolished and its bricks used for various canal repairs.


The plane today

The remains of the plane can still be seen, and the site explored by visitors (to a limited extent).

In the building alongside the locks, the former boiler house for the plane’s steam engine, there is a small museum covering the history of the locks and the plane, and other aspects of the local canal.

The mooring bollards from the incline can be found alongside the locks.


Restoration

The site of the Foxton Inclined Plane Boat Lift has been recognised as a Scheduled Ancient Monument and is on the Buildings at Risk Register. This recognition, together with the steady increase in leisure boating on British canals, means its restoration is now considered a key project in the development of the national waterway network.

The cost of full restoration has been estimated at £9 million (2006 figures), and is to be tackled in a series of stages.

Stage 1 of the project — the clearing of the site and restoration of the canal arms above and below the plane — is already underway. A grant for £1.7 million has been received from the Heritage Lottery Fund towards the £2.8 million cost of this first stage.

Fund-raising is currently underway to raise the money for a full engineering study to determine the best way of recreating a working boat lift at Foxton.


References

  • Uhlemann, H-J., (2002), Canal Lifts and Inclines of the World, Internat Limited, ISBN 0 95431 811 0


External links

  • Foxton Locks and Partnership
  • Foxton Inclined Plane Trust

McHenry Dam

The McHenry Dam is the only dam on the Fox River (Illinois, USA) that is serviced by a lock system. It is located in McHenry County, Illinois and was built in 1907.

The lock operates for all powered, sail driven, or paddle propelled canoes or boats, even float tubes, at no charge.


External links

  • McHenry Dam picture
  • McHenry Dam Lock

Floorplanning

Floorplanning is the act of designing a birds eye view of a structure. In terms of electronic design automation, floorplanning takes in some of the geometrical limitations in a design. Examples of this are

  • bonding pads for contacting off-chip (often using wire bonding) are normally located at the circumference of the chip
  • line drivers often have to be located as close to bonding pads as possible
  • chip area is therefore in some cases given a minimum area in order to fit in the required number of pads
  • areas are clustered in order to limit data paths thus frequently featuring defined structures such as cache RAM, multiplier, barrel shifter, line driver and arithmetic logic unit
  • purchased intellectual property blocks (such as an ARM core) come in ready defined area blocks.
  • some IP-blocks come with legal limitations such as permitting no routing of signals directly above the block


External links

  • The PLAYOUT Chip Planner


References

  • Analog VLSI Design Automation, by Sina Balkir, Günhan Dündar, A. Selcuk Ögrenci, CRC Press, ISBN 978-0849310904, 2003.

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ACM Transactions on Graphics

ACM Transactions on Graphics (TOG) is a quarterly scientific journal that aims to disseminate the latest findings of note in the field of computer graphics. It has been published since the 1970s by the Association for Computing Machinery. Starting in 2003, all papers accepted for presentation at the annual SIGGRAPH conference are printed in a special summer issue of the journal.

The journal is describes as follows on the ACM Digital Library website:

“ACM Transactions on Graphics (TOG) is the foremost peer-reviewed journal in graphics field. In the colorful pages of TOG, leading researchers discuss breakthroughs in computer-aided design, synthetic image generation, rendering, solid modeling and other areas. “Research,” the largest regular section, is necessary intellectual nourishment for anyone implementing graphics systems.” [1]

The current editor-in-chief is John Hart of the University of Illinois at Urbana-Champaign.


Impact

The journal’s is estimated to be the 89th most impactful journal in the field of computer science as of May 2003. In the whole field of computer science it was located at the top 7.28% percentile. [2] This was prior to the merger of the SIGGRAPH (9th most impactful and top 0.73% percentile as of 2003) and ACM Transaction on Graphics publications that began in 2003.

The ranking of computer graphics publications within the general field of computer science is as follows [3]:

  • 9. SIGGRAPH: 2.53 (top 0.73%)
  • 89. ACM Transactions on Graphics: 1.57 (top 7.28%)
  • 105. IEEE Transactions on Visualization and Computer Graphics: 1.53 (top 8.59%)
  • 249. Computer Graphics Forum: 1.07 (top 20.39%)
  • 269. Computer Vision, Graphics, and Image Processing: 1.04 (top 22.03%)
  • 678. IEEE Computer Graphics and Applications: 0.42 (top 55.52%)
  • 816. Advances in Computer Graphics Hardware: 0.28 (top 66.83%)
  • 833. Computer Graphics International: 0.27 (top 68.22%)
  • 939. International Journal of Image and Graphics: 0.19 (top 76.90%)
  • 998. Advances in Computer Graphics: 0.15 (top 81.73%)


See also

  • Association for Computing Machinery
  • SIGGRAPH


External links

  • ACM Transactions on Graphics website
  • ACM TOG Entry Point on the ACM Digital Library website

Vendor lock-out

Vendor lock-out occurs when a software vendor uses proprietary formats, lack of configurability or other means to prevent a user from using the vendor’s product in conjunction with products from other vendors.

The opposite of lock-out is integrable. This is not the same as integrated. Many products that suffer from lock-out are described as “integrated solutions”, but often do not allow further integration. Lock-out tactics are beneficial to vendors as they coerce users into purchasing more products from that same vendor.

Users of free software, “free” in the FSF sense, are generally protected from vendor lock-out. Because any motivated programmer can modify free software, lock-out is a temporary situation, and its market benefits are unlikely to outweigh the repercussions from users who may switch distributors.


Examples

  • A word processor which does not allow the user to use an external spell-checker, grammar checker, etc. — the word processor locks out other tools.
  • An Integrated Development Environment (IDE) that will not let you use external tools, such as source-code analysis or compilers for other languages.


See also

  • Vendor lock-in

Haffenreffer Museum of Anthropology

The Haffenreffer Museum of Anthropology is Brown University’s anthropology museum, set within 376 acres (1.52 km²) of woodland on the shores of Mount Hope Bay on Tower Street, Bristol, Rhode Island, and with a satellite location on the university campus in Providence, Rhode Island. The Museum grounds on Mount Hope (Rhode Island) include King Philip’s Seat, a large rock formation where Wampanoag chief King Philip held meetings.

The museum and its Bristol grounds were donated to Brown by the family of Rudolf F. Haffenreffer in 1955. It is one of the finest centers in New England for research on Native American material culture. Its holdings total more than 110,000 items, of which 73,000 are archaeological artifacts and 15,000 are ethnographic. While strongest in Native North American materials, the museum also contains significant material from Latin America, Africa, the Middle East, and Asia, including:

  • 69,966 archeological and 6,000 ethnological objects from North America
  • 2,534 archeological and 3,000 ethnological items from South and Central America
  • 40 archeological and 3,000 ethnological items from Africa, some by contemporary artisans
  • 399 archeological and 400 ethnological items from Europe
  • 1,100 ethnological items from Asia
  • 5 archeological and 1,500 ethnological items from Oceania

The museum is also a federally-designated repository for 20,000 archaeological objects excavated by Arctic researchers from National Park Service and Bureau of Land Management lands in Alaska.


External links

  • The Haffenreffer Museum of Anthropology, Brown University

Brandy Pond

Brandy Pond is a small lake in Naples, Maine, United States, that is connected to Long Lake by the Chute River which at one time was regarded by The Guinness Book of World Records as the world’s shortest river. Brandy Pond is connected to Sebago Lake by the Songo River. To get to Sebago Lake through the Songo River you must pass through the Songo locks, one of the last remaining hand operated locks in the country.
Brandy Pond is bounded by a commercial or downtown area called the “causeway” on Rt. 302. An area of homes on the southerly side called Scenic Drive and a golf course on the northern side as well as many private homes and public campgrounds and condominiums.

Blistex

Blistex is a company based in Oak Brook, Illinois that primarily manufactures lip balm, lip ointment, and other lip-related products. It also produces:

  • Stri-Dex – acne-prevention product
  • Kank-A – two varieties: 1) provides oral pain relief against canker sores 2) soft gel that provides oral pain relief of toothaches
  • Foille – relief of pain due to scrapes, cuts, minor burns, sunburn, non-poisonous insect bites, and minor skin irritation
  • Ivarest – relief of poison ivy itching
  • Glysomed – hand cream and body lotion for relief of dry skin by providing and locking in moisture


External links

  • Blistex Official website

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Ring of integers

In mathematics, the ring of integers is the set of integers made an algebraic structure Z with the operations of integer addition, negation, and multiplication. It is a commutative ring, and is the prototypical such by virtue of satisfying only those equations holding of all commutative rings with identity; indeed it is the initial commutative ring, as well as being the initial ring.

More generally the ring of integers of an algebraic number field K, often denoted by OK, is the ring of algebraic integers contained in K.

Using this notation, we can write Z = OQ since Z as above is the ring of integers of the field Q of rational numbers. And indeed, in algebraic number theory the elements of Z are often called the “rational integers” because of this.

An alternative term is maximal order, since the ring of integers of a number field is indeed the unique maximal order in the field.

The ring of integers OK has an integral basis; by this we mean that there exist b1,…,bn ∈ OK (the integral basis) such that each element x in OK can uniquely be represented as

<math>x=\sum_{i=1}^na_ib_i,</math>

with ai ∈ Z.


Examples

If ζ is a pth root of unity and K=Q(ζ) is the corresponding cyclotomic field, then an integral basis of OK is given by (1,ζ,ζ2,…,ζp-2).

If d is a square-free integer and K=Q(d1/2) is the corresponding quadratic field, then an integral basis of OK is given by (1,(1+d1/2)/2) if d≡1 (mod 4) and by (1,d1/2) if d≡2 or 3 (mod 4).

Lock

For information on “locked” Wikipedia pages, see .

Lock may refer to:


People

  • Lock (surname)
  • Goldilocks, and the three bears.


Things

  • Lock (device), a mechanical device used to keep a door or any other barrier closed.

    • Bored cylindrical lock
    • Combination lock
    • Electronic lock
    • Ignition lock
    • Lock pick
    • Locksmithing
    • Mortice lock
    • Padlock
    • Warded lock
  • One of the rugby union positions or rugby league positions.
    • Lock (Rugby League) a player position in Rugby League.
    • Lock (Rugby Union) a player position in Rugby Union.
  • Short name for joint locks or grappling holds in combat sports.
  • Lock (firearm), the ignition mechanism used on early projectile weapons.
    • Snaplock
    • Flintlock
    • Matchlock
  • Lock (water transport), an enclosure in a navigable canal or river which enables ships and boats to pass between sections of the waterway at different levels.
  • Lock of hair, a tuft or small bundle of hair,
  • Lock (computer science), a bookkeeping object associated with a piece of data that is used to serialize concurrent access.
  • Lock (Saga of the Skolian empire), a sentient machine in the novels by Catherine Asaro.
  • Lock (telemetry), when the output data and clock signals match those of an input signal transmitted and sent through a bit synchronizer, a device that establishes a series of clock pulses which are synchronous to the incoming signal.
  • Lock (spacecraft), a positional fix on another object, or it can mean lock on telemetry data.
  • Lock (weapons guidance), an indication the missile seeker system has a suitable or adequate acquisition fix to hit successfully if launched.
  • “Locked,” a song my Mutha’s Day Out


Places

  • Lock, South Australia


See also

  • Airlock
  • Interlocking
  • Locke
  • Lox

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.

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.

Readers-writer lock

In computer science, a readers-writer lock (also known by the name multi-reader lock, or by typographical variants such as readers/writers lock) is a synchronization primitive that solves one of the readers-writers problems. A readers-writer lock is like a mutex, in that it controls access to some shared memory area, but it allows multiple threads to read from the shared area concurrently. Any thread that needs to write to the shared memory, of course, needs to acquire an exclusive lock.

Readers-writer locks are usually constructed on top of mutexes and condition variables, or on top of semaphores. They are rarely implemented from scratch.

Stateless server

A stateless server is a server that treats each request as an independent transaction that is unrelated to any previous request.


Advantages

This simplifies the server design because it does not need to dynamically allocate storage to deal with conversations in progress or worry about freeing it if a client dies in mid-transaction.


Disadvantages

A disadvantage is that it may be necessary to include more information in each request and this extra information will need to be interpreted by the server each time.


Examples

An example of a stateless server is a World Wide Web server. With the exception of cookies, these take in requests (URLs) which completely specify the required document and do not require any context or memory of previous requests.

Contrast this with a traditional FTP server which conducts an interactive session with the user. A request to the server for a file can assume that the user has been authenticated and that the current directory and file transfer mode have been set.

The Gopher protocol and [[Gopher+]] are both designed to be stateless.


References

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Door furniture

Door furniture (British and Australian English) or Door hardware (North American English) refers to any of the items that are attached to a door or a drawer to enhance its functionality or appearance.

Design of door furniture is an issue to disabled persons who might have difficulty opening or using some kinds of door, and to specialists in Interior design as well as those usability professionals which often take their didactic examples from door furniture design and use.

Items of door furniture or door hardware include:

  • fingerplate
  • keyhole
  • lock
  • doorknob (or doorhandle)
  • door knocker
  • thumb latch
  • hinge
  • pull handle
  • letter plate (or letter box)
  • peephole or wide-angle door viewer
  • door stop
  • escutcheon
  • bell push
  • espagnolette
  • rim lock

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Kilometrico

Kilometrico is a common model of ballpoint pen made by Papermate. It is available in red, blue, and black, in different point sizes. Kilometrico pens are inexpensive and write smoothly, but are also prone to leaking in some circumstances. Kilometrico pens are very reliable and work well in most circumstances. They are suited to tasks requiring a fine line like writing in comparison to colouring a large area.

The pens are so named because they are advertised to be able to write for one kilometre. In most cases they write for more than one kilometer.

Great Lakes Waterway

The Great Lakes Waterway is a system of channels and canals that makes all of the Great Lakes accessible to oceangoing vessels. Its principal civil engineering components are the Welland Canal, bypassing Niagara Falls between Lake Ontario and Lake Erie, and the Soo Locks, bypassing the rapids of the St. Marys River between Lake Superior and Lake Huron, at Sault Sainte Marie. Maintained channels serve the St. Clair River and Detroit River between Lake Huron and Lake Erie. A United States Coast Guard icebreaker helps keep the passage open for much of the winter, although shipping usually ceases for 2 or 3 months each year.

The Great Lakes Waterway is supplemented by the Saint Lawrence Seaway, which makes the Saint Lawrence River navigable from Montreal to Kingston, Ontario. The two waterways are often jointly referred to as the St. Lawrence Seaway. The Great Lakes Seaway has larger locks and deeper drafts than the St. Lawrence Seaway with the result that a number of lake freighters are confined to the lakes, being small enough to operate on the Waterway but too large to pass down the Seaway.

The Great Lakes Waterway is co-administered by Canada and the United States.

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Left wing lock

The left wing lock is a defensive ice hockey strategy similar to the neutral zone trap.
In the most basic form, once puck possession changes, the left wing moves back in line with the defencemen.
Each defender (including the left winger) play a zone defence and are responsible for a third of the ice each.
Since there are normally only two defencemen, this tactic helps to avoid odd man rushes.

With the reinforced defensive line, the center and right wing forecheck aggressively.
Often the forecheckers will try to drive the puck over to the opponents right wing.

Although the ‘lock’ was made famous by the Detroit Red Wings and has been used to great success in their Stanley Cup runs in the past decade, they are not credited with inventing it.
The standard story was that the lock was invented in Czechoslovakia to work against the dominant Soviet teams of the 1970s.

The simplicity of the lock has made it popular at all levels of hockey and it is not uncommon to see it implemented in youth hockey.


External links

  • How to Run a Hockey Defense: Left Wing Lock

Inertial mass

Inertial mass is a measure of the resistance of an entity to a change in its velocity relative to an inertial frame. The inertial frame does not have to be that of the mass in question; either before or after the measurement.</br>
This ‘resistance’ is also sometimes called inertia.

Within classical physics the inertial mass of point particles is defined by means of the following equation for the subsequently described Machian thought experiment where particle 1 is taken as a unit (m1 =1):

mi ai1 = m1 a1i,

where mi is the inertial mass of particle i, and ai1 is the initial acceleration of particle i, in the direction from particle i to particle 1, in a volume occupied only by particles i and 1, where both particles are initially at rest one distance unit apart. There are no external forces, but the particles exert a force on each other.

The equation defines inertial mass of particle i in terms of the assumed measurable mutually induced accelerations ai1 and a1i. The remaining constraints on the accelerations, that the above defining equation still holds at different initial distances and when generated by the pairing of particles with other than particle 1, can be taken as requirements for the experimental validity of the theory’s dynamics, cf. momentum conservation. In addition, the requirement that the paired accelerations used are colinear, irrelevant of the direction chosen for the alignment of the particles, verifies that they are measured relative to an inertial frame in a force-free volume.

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Goring Lock

Goring Lock is a lock and weir situated on the River Thames at the Goring Gap in England. The lock is located between the twin villages of Goring-On-Thames, Oxfordshire, and Streatley, Berkshire, and is adjacent to Goring and Streatley Bridge. The lock is owned and managed by the Environment Agency.


Access to the lock

The lock is situated almost under the bridge and is easily accessible from both Goring and Streatley


Reach above the lock

The reach is only just over half a mile long. The Thames Path crosses the bridge to Streatley and continues on the western bank to Cleeve Lock.


See also

  • Locks on the River Thames

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Read/write lock pattern

A read/write lock pattern is a software design pattern that allows concurrent read access to an object but requires exclusive access for write operations.

In this pattern, multiple readers can read the data in parallel but needs exclusive lock while writing the data. When writer is writing the data, readers will be blocked until writer is finished writing.


See also

  • Lock pattern
  • Scheduler pattern
  • Balking pattern
  • Lock (software engineering)