Luggage strap 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.

{{UK-canal-stub}

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Cookham Lock is a lock and weir situated on the River Thames near Cookham, Berkshire. It is owned and managed by the Environment Agency. The lock is set in a lock cut which creates Formosa Island and it is surrounded by woods.

Access to the lock

There is a road from Cookham to Formosa Island and the lock.

Reach above the lock

The river is picturesque and described as Wind in the Willows country. Kenneth Graham based much of his book on this part of the Thames.

Literature and the Media

Cookham was home to the artist Stanley Spencer’s whose works include Swan Upping at Cookham.

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A canal pound is the stretch of level water impounded between two canal locks. Canal pounds can vary in length from the non-existent, where two or more immediately adjacent locks form a lock staircase, to many miles.

History

Pounds came into being with the development of Pound locks to replace the earlier flash locks. A key feature of pound locks was that the intervening level between locks remained largely constant, as opposed to the varible levels created by the opening of flash locks.

Types of pound

Pounds can be described in various ways according to their situation;

Summit pound

A summit pound is formed at a summit on the canal, and where all the defining locks descend from the pound. Summit pounds are particularly important in canal design, as every boat entering or leaving the pound causes a loss of water. Summit pounds therefore need an independent form of water supply, which may take the form of weirs on adjacent rivers, reservoirs or pumping stations. Common practice during canal design was to make summit pounds as large as practically possible, in order that losing a lockful of water would not lower the water level too significantly. The Rochdale Canal is a good example of a canal with a relatively short summit pound, which requires restrictions on lock workings at certain times.

Sump pound

The inverse of a summit pound is a sump pound. In contrast to a summit pound, a sump pound is a point where every boat entering or leaving the pound causes an addition of water.

Lock pound

A pound which lies between two locks which lie only a short distance apart. Water levels in the pound are liable to fluctuate as the locks are used.

Side pound

A particular type of extremely short lock pound, which is extended sideways to make up for the short distance between locks so as to avoid excessive level fluctuations. Side pounds should not be confused with side ponds (without the u).

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County Lock is a lock on the River Kennet in Reading town centre in the English county of Berkshire. It was built between 1718 and 1723 under the supervision of the engineer John Hore of Newbury, and this stretch of the river is now administered by British Waterways and known as the Kennet Navigation.

County Lock is the shallowest of the locks on the Kennet, as boats only rise or fall about 30 cm (1 foot) in the lock. The main stream of the Kennet flows down the weir on the far side of the lock, whilst another arm of the Kennet disappears under the Bridge Street Roundabout.

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In computer science, multiple granularity locking (MGL), sometimes called the John Rayner locking method, is a locking method used in database management systems (DBMS) and relational databases.

In MGL, locks are set on objects that contain other objects. MGL exploits the hierarchical nature of the contains relationship. For example, a database may have files, which contain pages, which further contain records. This can be thought of as a tree of objects, where each node contains its children. A lock locks a node and its descendants.

Multiple granularity locking is usually used with Non-strict two-phase locking to guarantee serializability. MGL uses lock escalation to determine granularity lock on a node and its ancestors.

Lock Modes

In addition to shared (S) locks and exclusive (X) locks from other locking schemes, like Strict two-phase locking, MGL also uses intention shared and intention exclusive locks. IS locks conflict with X locks, while IX locks conflict with S and X locks. The null lock (NL) is compatible with everything.

To lock a node in S (or X), MGL has the transaction locks all of its ancestors with IS (or IX), so if a transaction locks a node in S (or X), no other transaction can access its ancestors in X (or S and X).

MGL locking modes are compatible with each other as defined in the following matrix.

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In Databases and Transaction processing, Two phase locking, (2PL) is a concurrency control locking protocol, mechanism, that guarantees Serializability. It is also the name of a class (set) of transaction schedules. Using locks that block processes, 2PL is subject to deadlocks that result from the mutual blocking of two transactions or more.

Two phase locking

According to the Two phase locking protocol, locks are handled by a transaction in two distinct, consecutive phases during the transaction’s execution:

Phase 1: Locks are acquired and no locks are released.

Phase 2: Locks are released and no locks are acquired.

The serializability property is guaranteed for a schedule with transactions that obey the protocol. The 2PL schedule class is defined as the class of all the schedules comprising transactions with data access orders that could be generated by the 2PL protocol.

Strict two phase locking

The Strict two phase locking (S2PL) class of schedules is the intersection of the 2PL class with the class of schedules possessing the Strictness property.

To comply with the S2PL protocol a transaction needs to comply with 2PL, and release its write (exclusive) locks only after it has ended, i.e., being either committed or aborted.

S2PL is a special case of 2PL, i.e., the S2PL class is a proper subclass of 2PL.

Strong strict two phase locking

To comply with the Strong strict two phase locking (SS2PL) protocol a transaction needs to comply with 2PL, and release both its write (exclusive) and read (shared) locks only after it has ended, i.e., being either committed or aborted.
A transaction obeying SS2PL can be viewed as having Phase 1 that lasts its entire execution duration, and no Phase 2 (or degenerate Phase 2). Thus, only one phase is actually left, and “two-phase” in the name seems to be still utilized due to the historical development of the concept from 2PL. The SS2PL property of a schedule is also called Rigorousness, and an SS2PL schedule is also called a Rigorous schedule.

SS2PL is a special case of S2PL, i.e., the SS2PL class of schedules is a proper subclass of S2PL (every SS2PL schedule is also an S2PL schedule, but S2PL schedules exist that are not SS2PL).

SS2PL is the concurrency control protocol of choice for most database systems since it provides besides serializability also Strictness, which is instrumental for efficient database recovery, and also Commitment ordering (CO) for participating in environments where a CO based Global serializability solution is employed.

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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.

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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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The Sault Locks (usually called the Soo Locks) allow ships to travel between Lake Superior and the lower Great Lakes. The locks are the busiest in the world, passing an average of 12,000 ships (”boats” in Great Lakes parlance) per year. This is achieved in spite of the locks being closed during the winter months, January through March, when ice shuts down shipping on the Great Lakes. The winter months are used to inspect and maintain the locks.

The locks bypass the rapids of the St. Marys River where the water falls 7 meters (21 feet) from Lake Superior. Sault Ste. Marie (pronounced Soo Saint Ma-ree) gives its name to both the Canadian and American cities at the site, in Ontario and Michigan, respectively. The Sault Ste. Marie International Bridge between the United States and Canada permits vehicular traffic to pass over the locks.

American locks

The American locks form part of a 1.6 mile (2.6 km) canal formally named the St. Marys Falls Ship Canal. They are owned and maintained by the United States Army Corps of Engineers. The first American locks were completed in May 1855.

• Davis Lock was built in 1914. It is 411 meters (1350 feet) long, 24 meters (80 feet) wide and 7 meters (23.1 feet) deep. The Davis lock is used rather infrequently to lock light freighters, tour boats, and small craft when traffic warrants. SS James A Farrell was the first vessel to lock through.

• Sabin Lock was built in 1919. It is 1350 feet long, 80 feet wide, and 23.1 feet deep. This lock is decommissioned and no longer used.

• MacArthur Lock was built in 1943. It is 244 meters (800 feet) long, 24 meters (80 feet) wide and 9 meters (31 feet) deep. This is large enough to handle ocean going vessels that must first pass through the smaller locks in the Welland Canal. First vessel through was the SS Carl D. Bradley.

• Poe Lock was re-built in 1968, after the Saint Lawrence Seaway had opened. It is 366 meters (1200 feet) long, 34 meters (110 feet) wide and 10 meters (32 feet) deep. It can take ships carrying 72,000 tons of cargo. The Poe is the only lock that can handle the large lakers used on the upper lakes.

There is a project, as yet unfunded, to built a new large lock to replace the Davis and Sabin locks.

Engineers Day

On the last Friday of every June, the public is allowed behind the security fence and cross the lock gates of the American Locks for the annual Engineers Day Open House.[1] Visitors are able to get close enough to the ships passing through the two operating locks to touch them.

Canadian locks

Canadian lock, the only lock on the Ontario side, was built in 1895. It broke down in 1987 and a new lock was built within the old lock. The lock was reopened in 1998 and is used for recreation and tour boats. It is 76 meters long, 16 meters wide and 3 meters deep.

The Sault locks are a well developed tourist site that offers viewing stands to watch the locks at work and tour boat trips through the locks. It is now designated a National Historic Site of Canada (see: Sault Ste. Marie Canal).

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Route 75 is a scenic route from the Hartford area into Agawam, Massachusetts. It parallels Route 159 to the west.

Route description

Route 75 begins at Route 159 in Windsor, then passes through Windsor Locks near Bradley International Airport. It then continues north through Suffield and finally into Agawam, Massachusetts.

Special designations

Route 75 within the town of Suffield is a designated state scenic road.

History

Route 75 was created in 1932 from portions of old State Highway 110 that were not assigned to US 5A (now Route 159). The route was extended into Massachusetts in 1950.

Junction list

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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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A tubular pin tumbler lock, also known as Ace lock or “axial pin tumbler lock” or “radial lock”, is a variety of pin tumbler lock in which 6-8 pins are arranged in a circular pattern, and the corresponding key is tubular or cylindrical in shape.

J.A. Blake is credited with patenting the first tubular lock in 1833. Walter R. Schlage continued the development of the tubular lock. He was awarded 11 patents, and his improvements made the tubular lock what it is today.

Tubular locks are commonly seen on bicycle locks, computer locks, and a variety of coin-operated devices such as vending machines and coin-operated washing machines.

Security

Tubular pin tumbler locks are generally considered to be safer and more resistant to picking than standard locks, though there are several ways to open them without a key. Even though the pins are exposed, making them superficially easier to pick, they are designed such that after all pins are manipulated to their shear line, once the plug is rotated 1/6 to 1/8 around, the pins will fall into the next pin’s hole, requiring re-picking to continue. As such, picking the lock without using a device to hold its pins in place once they reach their shear line requires over a dozen complete picks to unlock and relock.

Such locks can be picked by a special tubular lock pick with a minimum of effort in very little time; it is also possible to defeat them by drilling with a special “hole saw” drill bit. Standard tubular lock drill bit sizes are .375″ (9.53 mm) diameter and .394″ (10 mm) diameter.[1] To prevent drilling, many tubular locks have a middle pin made of hardened steel, or contain a ball bearing in the middle pin.

In 2004, videos circulating on the Internet demonstrated that some tubular pin tumbler locks could be easily opened with the shaft of an inexpensive ballpoint pen (e.g. BIC brand) of matching diameter. Trade website BikeBiz.com revealed that the weaknesses of the tubular pin tumbler mechanism had first been described in 1992 by UK journalist John Stuart Clark (see Kryptonite lock).

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Miraflores is the name of one of the three locks that form part of the Panama Canal and the name of the small lake that separates these locks from the Pedro Miguel locks upstream. In the Miraflores locks, vessels are lifted (or lowered) in three stages totalling 8 m, allowing them to transit to or from the Pacific Ocean port of Balboa (near Panama City). Ships cross below the Puente de las Américas (Bridge of the Americas) which connects North and South America.

As of 2005, the following schedule was in effect for ship transit through the locks. From 06:00 to 15:15, ships travel from the Pacific towards the Atlantic. From 15:45 to 23:00 ships travel from the Atlantic towards the Pacific. At any other time, travel is permitted in both directions,

A modern visitor center allows tourists to have a full view of the Miraflores locks operation. Binoculars are recommended to also see the Pedro Miguel locks, visible in the distance. As of 2005, admittance to the visitors center costs US$5 (observation terrace) or $8 (supporting exhibits and show added). Viewing a transit operation at the center can take more than 30 minutes. A souvernirs shop in the base level sells related merchandise. The center closes at 17:00.

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Power door locks (aka electric door locks or central locking) allow the driver or front passenger to simultaneously lock or unlock all the doors of an automobile or truck, by pressing a button or flipping a switch.

Power door locks were introduced on the luxury Scripps-Booth in 1914, but were not common on luxury cars until Packard reintroduced them in 1956. Nearly every car model today offers this feature as at least optional equipment.

Early systems locked and unlocked only the car doors. Many cars today also feature systems which can unlock such things as the luggage compartment or fuel filler cap door.

It is also common on modern cars for the locks to activate automatically when the car is put into gear or reaches a certain speed. Automatic unlocking when the car is parked is usually also featured on such systems.

Remote and handsfree

Today, many cars with power door locks also have a remote keyless system, which allows a person to press a button on a remote control (or, on some Ford cars and trucks, enter a combination on an external keypad) to unlock the car without using a key. This system confirms successful (un-)locking through either a light or a horn signal, and usually offers an option to switch easily between these two variants. Both provide almost the same functionality, though light signals are more discreet while horn signals might create a nuisance in residential neighborhoods and other busy parking areas (e.g. short-term parking lots).

Other cars have a proximity system that is triggered if a keylike transducer (Advanced Key or handsfree) is within a certain distance of the car.

Finally, some other includes garage door opener, integrated.

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A bahut is a portable coffer or chest, with a rounded lid covered in leather, garnished with nails, once used for the transport of clothes or other personal luggage, it was, in short, the original portmanteau. This ancient receptacle, of which mention is made as early as the 14th century — its traditional form is still preserved in many varieties of the travelling trunk — sometimes had its leather covering richly ornamented, and occasionally its interior was divided into compartments; but whatever the details of its construction it was always readily portable. Towards the end of the 17th century the name fell into disuse, and was replaced by coffer, which probably accounts for its misuse by the French romantic writers of the early 19th century. They applied it to almost any antique sideboard, cupboard or wardrobe, and its use became hopelessly confused.

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