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Lock of hair

A lock of hair is a piece or pieces of hair that has been cut from, or remains singly on, a human head, most commonly bunched or tied together in some way.

Locks of hair carry symbolic value and have been utilized throughout history in various religious, superstitions, and sentimental roles.

  • A primitive belief maintains that owning a lock of hair from another’s head gives one power over that individual, in the same manner that owning a piece of clothing or image of an individual grants the owner such powers.
  • During antiquity, girls who were about to be married offered locks of hair to the forest god Virbius (Virbio).
  • An ancient and worldwide (eg. China, Egypt, Thailand, Albania, Ukraine, India, Israel, etc) pre-adolescent custom was to shave children’s heads but leave a lock of hair (sometimes several locks) remaining on their heads. Upon reaching adulthood the lock of hair was usually cut off (see rites of passage).
  • The scalp lock was a lock of hair kept throughout a man’s life. Like the childhood locks mentioned above, the scalp lock was also a worldwide phenomenon, particularly noted amongst eastern woodland Indians (see Iroquois, Huron, Mahican, Mohawk) in north America (see also scalping and mohawk hairstyle).

Sviatoslav I of Kiev was reported to have worn a scalp lock by Leo the Deacon, a Byzantine historian . Later Ukrainian Cossacks (Zaporozhians) sported scalp locks called oseledets or khokhol. In India this custom remains active but usually only amongst orthodox Hindus. See sikha.

In Mark Twain’s travel book ‘The Innocents Abroad’, he describes Moroccan men sporting scalp locks.

  • A common superstition holds that a lock of hair from a baby’s first haircut should be kept for good luck. An old Irish superstition holds that it is unlucky to accept a lock of hair (or a four-footed beast) from a lover.
  • A lock of Beethoven’s hair, cut from his head in 1827, was auctioned in 1994 through Sotheby’s of London.[1] Research on the hair determined that the composer’s life-long illness was caused by lead poisoning.


Sources

  • The Innocents Abroad by Mark Twain - Signet Classic, ISBN 1-85532-848-8
  • Armies of Medieval Russia 750-1250 by David Nicolle - Osprey Publishing, ISBN 0-451-52502-7
  • Daily Life in Ancient India From 200 BC to 700 AD by Jeannine Auboyer - Phoenix Press, ISBN 1-84212-591-5
  • The Cossacks by John Ure - The Overlook Press, ISBN 1-58567-138-x
  • Ancient Egyptian Hairstyles
  • Ukrainian Cossack Display Group
  • Common Superstitions
  • Ancient Legends, Mystic Charms, and Superstitions of Ireland


see also

  • Dreadlocks, commonly called locks or dreads.

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Linus Yale

The name Linus Yale refers to:

  • Linus Yale, Sr., an American inventor and manufacturer of pin-tumbler locks, or to his son,
  • Linus Yale, Jr., who joined him in the business and was an innovator in cylinder lock technology.

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Lex Fufia Caninia

In ancient Rome, the lex Fufia Caninia (2 BC) was one of the laws that national assemblies had to pass, after they were requested to do so by Augustus. This law, along with the lex Aelia Sentia, placed limitations on manumissions. In numerical terms this meant that a master who had three slaves could free only two; one who had between four to ten could free only half of them; one with eleven to thirty could free only a third, and so on. Manumissions above these limits were not valid.

The limitations were established at the end of the Republic and the beginning of the Empire, at a time when the number of manumissions was so large that they were perceived as a challenge to a social system that was founded on slavery.


Relevant articles

  • Roman Law
  • Status in Roman legal system
  • List of Roman laws
    • Lex Aelia Sentia


External links

  • The Roman Law Library, incl. Leges
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Lockring

For the Bronze Age jewellery, see lock ring.

A lock ring is a threaded washer used to prevent components from becoming loose during rotation. They are found on a bottom bracket and a track hub of a bicycle. Lokring is another form of fastener used in the automotive and air condition industries. These fittings are often confused with lockrings.

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D’Hondt

D’Hondt can refer to:

  • D’Hondt method, a method for allocating seats in party-list proportional representation political election systems
  • Victor D’Hondt (1841–1901), a Belgian lawyer, professor and mathematician

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WebMoney

WebMoney is an electronic money and online payment system (transactions are conducted through WebMoney Transfer). WM Transfer Ltd, the owner and administrator of WebMoney Transfer Online Payment System, was founded in 1998 and is a legal corporate entity of Belize, Central America. Originally targeted mainly at Russian clients, it is now used world-wide. The company claims to have more than 2 million users.

Clients can use the system through downloaded software called “WM Keeper” or through a limited web client called “WM Keeper light”. Signing up and receiving webmoney (known as “WM units”) from other users is free; sending WM units to other accounts incurs a fee of 0.8%. Funds can be deposited into or withdrawn from webmoney accounts by money order, wire transfer, by conversion from other electronic currencies, or by cash transactions at authorized exchange offices; all of these incur various fees. It is also possible to purchase WM cards for $10-$100 in order to fund an account.

WebMoney transactions are safe because they do not require a credit card or bank account and immune against certain scams because they are final and cannot be retracted; this is similar to e-gold and cash and unlike credit card transactions and PayPal. It is therefore not possible to buy WM units online with a mere credit card or a paypal account.

Every account, known as a “purse”, is run in US Dollar-equivalents (WMZ), ruble-equivalents (WMR), euro-equivalents (WME) or hryvnia-equivalents (WMU). Accounts are identified by strings called WM-IDs; account holders can remain completely anonymous towards each other.

WebMoney incorporates an instant messaging system as well as a way to send out bills and to extend credit. It is also possible to protect a payment with a password; the payment is withdrawn from the payer’s account and added to the payee’s account, but cannot be redeemed unless the password is known. The payer will typically provide the password once the promised goods have been delivered. Some operations require a higher level of user authentication known as a “WM passport” which a user can obtain from authorized parties.

The main address for technical support is given in Moscow; the main proprietor and administrator is located in Belize. Transactions in WMR are underwritten by WMR LLC in Moscow and transactions in WME and WMZ are underwritten by Amstar Holdings Limited in Panama.


Made for CIS

Besides CIS and Eastern European countries, WebMoney has offices in such countries as USA, Netherlands, Germany, Spain, Japan, Greece, Israel, France, UAE.


Security

WebMoney has had its share of security vulnerabilities. Fraudsters have targeted users of WebMoney with a host of Trojans and mal-wares.


See also

  • PayPal
  • E-Gold
  • Pecunix


References

  • Payment Providers on Net Articles on world payment providers.
  • Webmoney Keeper Classic in Firefox A set of plugins and scripts allowing authorization with Webmoney Keeper Classic in Firefox
  • Security Issues with WebMoney Fraudsters migrate from e-Gold to WebMoney - June 2007


External links

  • WebMoney official site

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Maekawa’s algorithm

Maekawa’s Algorithm is an algorithm for mutual exclusion on a distributed system. The basis of this algorithm is a quorum like approach where any one site needs only to seek permissions from a subset of other sites.


Algorithm


Terminology

  • A site is any computing device which is running the Maekawa’s Algorithm
  • For any one request of the critical section:
    • The requesting site is the site which is requesting entry into the critical section.
    • The receiving site is every other site which is receiving the request from the requesting site.
  • ts refers to the local timestamp of the system according to its logical clock.


Algorithm

Requesting Site:

  • A requesting site <math>P_i</math> sends a message <math>request(ts, i)</math> to all sites in its quorum set <math>R_i</math>.

Receiving Site:

  • Upon reception of a <math>request(ts, i)</math> message, the receiving site <math>P_j</math> will:

    • If site <math>P_j</math> does not have an outstanding <math>grant</math> message (that is, a <math>grant</math> message that has not been released), then site <math>P_j</math> sends a <math>grant(j)</math> message to site <math>P_i</math>.
    • If site <math>P_j</math> has an outstanding <math>grant</math> message with a process with higher priority than the request, then site <math>P_j</math> sends a <math>failed(j)</math> message to site <math>P_i</math> and site <math>P_j</math> queues the request from site <math>P_i</math>.
    • If site <math>P_j</math> has an outstanding <math>grant</math> message with a process with lower priority than the request, then site <math>P_j</math> sends an <math>inquire(j)</math> message to the process which has currently been granted access to the critical section by site <math>P_j</math>. (That is, the site with the outstanding <math>grant</math> message.)
  • Upon reception of a <math>inquire(j)</math> message, the site <math>P_k</math> will:
    • Send a <math>yield(k)</math> message to site <math>P_j</math> if and only if site <math>P_k</math> has received a <math>failed</math> message from some other site or if <math>P_k</math> has sent a yield to some other site but have not received a new <math>grant</math>.
  • Upon reception of a <math>yield(k)</math> message, site <math>P_j</math> will:
    • Send a <math>grant(j)</math> message to the request on the top of its own request queue.
    • Place <math>P_k</math> into its request queue.
  • Upon reception of a <math>release(i)</math> message, site <math>P_j</math> will:
    • Delete <math>P_i</math> from its request queue.
    • Send a <math>grant(j)</math> message to the request on the top of its request queue.

Critical Section:

  • Site <math>P_i</math> enters the critical section on receiving a <math>grant</math> message from all sites in <math>R_i</math>.
  • Upon exiting the critical section, <math>P_i</math> sends a <math>release(i)</math> message to all sites in <math>R_i</math>.

Quorum Set (<math>R_x</math>):
A quorum set must abide by the following properties:

  1. <math>\forall i \forall j [R_i \bigcap R_j \ne \empty ]</math>
  2. <math>\forall i [ P_i \in R_i ]</math>
  3. <math>\forall i [ |R_i| = K ]</math>
  4. Site <math>P_i</math> is contained in exactly <math>K</math> request sets
Therefore:

  • <math>|R_i| \geq \sqrt{N-1}</math>


Performance

  • Number of network messages; <math>3 \sqrt{N}</math> to <math>6 \sqrt{N}</math>
  • Synchronization delay: 2 message propagation delays


See also

  • Lamport’s bakery algorithm
  • Lamport’s distributed mutual exclusion algorithm
  • Ricart-Agrawala algorithm
  • Suzuki-Kasami’s algorithm
  • Raymond’s algorithm


External links

  • “A sqrt(N) algorithm for mutual exclusion in decentralized systems” at The ACM Digital Library

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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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Mixed tensor

In tensor analysis, a mixed tensor is a tensor which is neither covariant nor contravariant. At least one of the indices of a mixed tensor will be a subscript (covariant) and at least one of the indices will be a superscript (contravariant).

A mixed tensor of type <math> \begin{pmatrix} M \\ N \end{pmatrix} </math>, with both M > 0 and N > 0, is a tensor which has M contravariant indices and N covariant indices. Such tensor can be defined as a linear function which maps an M+N-tuple of M one-forms and N vectors to a scalar.


Index raising and lowering

Consider the following octet of related tensors:

<math> T_{\alpha \beta \gamma}, \ T_{\alpha \beta} {}^\gamma, \ T_\alpha {}^\beta {}_\gamma, \

T_\alpha {}^{\beta \gamma}, \ T^\alpha {}_{\beta \gamma}, \ T^\alpha {}_\beta {}^\gamma, \
T^{\alpha \beta} {}_\gamma, \ T^{\alpha \beta \gamma} </math>.
The first one is covariant, the last one contravariant, and the remaining ones mixed. Notationally, these tensors differ from each other by the covariance/contravariance of their indices. A given contravariant index of a tensor can be lowered using the metric tensor gμν, and a given covariant index can be raised using the inverse metric tensor gμν. Thus, gμν could be called the index lowering operator and gμν the index raising operator.

Generally, the covariant metric tensor, contracted with a tensor of type <math>\begin{pmatrix} M \\ N \end{pmatrix} </math>, yields a tensor of type <math> \begin{pmatrix} M - 1 \\ N + 1 \end{pmatrix} </math>, whereas its contravariant inverse, contracted with a tensor of type <math>\begin{pmatrix} M \\ N \end{pmatrix} </math>, yields a tensor of type <math> \begin{pmatrix} M + 1 \\ N - 1 \end{pmatrix} </math>.


Examples

As an example, a mixed tensor of type <math> \begin{pmatrix} 1 \\ 2 \end{pmatrix} </math> can be obtained by raising an index of a covariant tensor of type <math> \begin{pmatrix} 0 \\ 3 \end{pmatrix} </math>,

<math> T_{\alpha \beta} {}^\tau = T_{\alpha \beta \gamma} \, g^{\gamma \tau} </math>,

where <math> T_{\alpha \beta} {}^\tau </math> is the same tensor as <math> T_{\alpha \beta} {}^\gamma </math>, because

<math> T_{\alpha \beta} {}^\tau \, \delta_\tau {}^\gamma = T_{\alpha \beta} {}^\gamma </math>,

with Kronecker δ acting here like an identity matrix.

Likewise,

<math> T_\alpha {}^\tau {}_\gamma = T_{\alpha \beta \gamma} \, g^{\beta \tau}, </math>
<math> T_\alpha {}^{\tau \epsilon} = T_{\alpha \beta \gamma} \, g^{\beta \tau} \, g^{\gamma \epsilon},</math>
<math> T^{\alpha \beta} {}_\gamma = g_{\gamma \tau} \, T^{\alpha \beta \tau},</math>
<math> T^\alpha {}_{\tau \epsilon} = g_{\tau \beta} \, g_{\epsilon \gamma} \, T^{\alpha \beta \gamma}. </math>

Raising an index of the metric tensor is equivalent to contracting it with its inverse, yielding the Kronecker delta,

<math> g^{\mu \lambda} \, g_{\lambda \nu} = g^\mu {}_\nu = \delta^\mu {}_\nu </math>,

so any mixed version of the metric tensor will be equal to the Kronecker delta, which will also be mixed.


See also

  • Tensor (intrinsic definition)

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Neptune’s Staircase

Neptune’s Staircase is a staircase lock comprising eight locks on the Caledonian Canal. It is the longest staircase lock in the United Kingdom, and lifts boats 64 feet (19.5 metres). The locks were originally hand-powered, but have been converted to hydraulic operation.
The base plinths of the original capstans are still present, although the capstans themselves are now gone.

The current lock gates weigh 22 tons each, and require a team of three lock-keepers (at minimum) to run the staircase.

It is usual for them to operate on an “Efficiency Basis”, that is the keepers try to either fill each cut with boats on the lift or drop, or to allow for passing, ie a dropping craft to pass a rising craft on the same fill/empty cycle.

It is one of the biggest staircases in Britain, and is kept by British Waterways.

It is located at Banavie, near Fort William just north of Loch Linnhe.

The structure was designed by Thomas Telford.

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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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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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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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In the Sky

“In The Sky” is Miz’s third single and first one to release since releasing two other albums, Say It’s Forever and Dreams. The title track is a Japanese re-make of Amazing, a song from her album Story Untold, and was used as the theme for the PS2 game Grandia III. What Difference, however, is a new song.


Track listing

  1. In The Sky
  2. What Difference
  3. In The Sky - Remix
  4. In The Sky (MUSIC TRACK)


Promotional video

The PV for this song was shot during Miz’s first visit to the US. It’s another nature PV, shot in a Californian desert. It also contains scenes of the two main characters from Grandia III.

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Snakeholme Lock

Snakeholme Lock is a brick chamber canal lock on the Driffield Navigation, in the East Riding of Yorkshire, England. It is notable in being a staircase lock, but only the upper lock is still used.


Location

It is 0.5 mile (0.8 km) south east from the village of Wansford, and is approximately 17 miles (27 km) north of Kingston upon Hull city centre.


Situated on the Driffield Navigation

  • Next location upstream = Wansford bridge
  • Next location downstream = Brigham


History

Built during the construction of the Driffield Navigation after the Act of Parliament in 1767. It was the first lock reached on the new section of canal, and became the tidal limit on the navigation. A swing bridge reached over the bottom of the lock to allow the Yorkshire Keels to get through without lowering the mast.

Once regular trade started to use the new navigation, problems with low water were noticed. The tide on the River Hull does not easily push up the river due to sharp bends, and narrow sections, and so there was regularly not enough depth over the bottom gate cill.

To remedy this situation, a new chamber was built below the lock creating a Staircase lock. Since the lock was only needed to get the boats over the lower cill, the bottom lock only had a minimum rise, and would not even be needed on good spring tides, or during high river flows. A sluice was built into the side of the chamber to allow emptying, filling being performed from the lock above.

During the navigation improvements of 1803-1811, a new lock at Struncheon Hill was built, keeping a permanent high water level at the lock, and it would be unlikely the lower chamber was used after this.

Trade declined on the navigation, but some of the last cargoes were to the mills at Wansford, and so kept the lock going for a few more years than the rest of the canal. In 1967 a trip to the lock showed it unnavigable, but in reasonable condition.

At some point the swing bridge was replaced with a fixed structure.

Occasional working parties by the Driffield Navigation Ammeninties Association kept the worst of the vegetation at bay through the 1980s, but it was only in 2002 that a grant allowed work to restore the structure back to working conditions. When the lock was drained, the original swing bridge turntable casting was found in the mud and saved for historical interest.

On the 18 April 2003, the lock was reopened to traffic by the Mayor of Driffield. Several boats made the trip to “The Trout” pub in Wansford, but large amounts of silt and a trout farm located just above the lock have limited the numbers of boats using this stretch.


External links

  • Driffield Navigation Website

53°59′3.08″N 0°22′21.49″W

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Seven Editions of the Divine Law

According to the Bible, God has a method of gradual revelation and publication of his law. It was first written on nature, next on man, then the fundamental principles on the tablets of stone. In due time, Jesus appeared as the perfect embodiment of the truth, which he illustrated in his own sinless life. Later came the entire Scriptures, the larger and completed written edition. It was God’s purpose that his law should also be written in the hearts of his people, with its precepts able to be “read” in their outward lives.

1. First Edition: Written on Nature - Psalms 19:1: “The heavens declare the glory of God; and the firmament sheweth his handiwork.”
2. Second Edition: Written on Conscience - Romans 2:15: “Which shew the work of the law written in their hearts, their conscience also bearing witness, and their thoughts the mean while accusing or else excusing one another.”
3. Third Edition: Written on Tablets of Stone - Exodus 24:12: “And the LORD said unto Moses, Come up to me into the mount, and be there: and I will give thee tables of stone, and a law, and commandments which I have written; that thou mayest teach them.”
4. Fourth Edition: Christ the Living Word - John 1:14: “And the Word was made flesh, and dwelt among us, and we beheld his glory, the glory as of the only begotten of the Father, full of grace and truth.”
5. Fifth Edition: The Entire Scriptures - Romans 15:4: “For whatsoever things were written aforetime were written for our learning, that we through patience and comfort of the scriptures might have hope.”
6. Sixth Edition: Written on the Heart - Hebrews 8:10: “For this is the covenant that I will make with the house of Israel after those days, saith the Lord; I will put my laws into their mind, and write them in their hearts; and I will be to them a God, and they shall be to me a people.”
7. Seventh Edition: Christians as Living Epistles - 2 Corinthians 3:2-3: “Ye are our epistle written in our hearts, known and read of all men: forasmuch as ye are manifestly declared to be the epistle of Christ ministered by us, written not with ink, but with the Spirit of the living God; not in tables of stone, but in fleshy tables of the heart.”

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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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Charles Read (mathematician)

Charles Read is a British mathematician and currently a professor of mathematics at the University of Leeds. He works in the area of functional analysis, and is best known for his work in the 1980s on the invariant subspace problem, where he showed that there do exist operators on certain Banach spaces which have no non-trivial invariant subspace.

He completed his PhD entitled ‘Some Problems in the Geometry of Banach Spaces’ at the University of Cambridge under the supervision of Béla Bollobás.


External links

  • Charles Read’s Homepage
  • Charles Read at the Mathematics Genealogy Project