Monday, December 31, 2007

The first bullets

Advances in one either resulted beginning or precipitated advances in the other. Originally, bullets were surrounding metallic or stone balls placed in front of an explosive charge of gun powder at the end of a closed tube. As firearms became more scientifically advanced, from 1500 to 1800, bullets changed very little. They remained uncomplicated round lead balls, called rounds, differing only in their diameter.

The development of the hand culverin and matchlock arquebus brought regarding the use of cast lead balls as projectiles. "Bullet" is consequential from the French word "boulette" which roughly means "little ball". The original musket bullet was a spherical lead ball two sizes slighter than the bore, wrapped in a loosely-fitted paper patch which served to hold the bullet in the barrel firmly upon the powder. (Bullets that were not firmly upon the concentrate upon firing risked causing the barrel to explode, with the condition known as a "short start".) The loading of muskets was, therefore, easy with the old smooth-bore Brown Bess and comparable military muskets. The original muzzle-loading rifle, on the other hand, with a more intimately fitting ball to take the rifling grooves, was loaded with difficulty, particularly when the bore of the barrel was dirty from previous firings ("fouled"). For this reason, early rifles were not generally used for military purposes. Early rifle bullets necessary cloth patches to grip the rifling grooves, and to hold the bullet securely against the powder.

The first half of the nineteenth century saw a different change in the shape and function of the bullet. In 1826, Delirque, a French infantry officer, imaginary a breech with abrupt shoulders on which a spherical bullet was rammed down until it caught the rifling grooves..

Tuesday, December 25, 2007

Bullet

A bullet is a rock-hard projectile propelled by a firearm or air gun and is normally made from metal (usually lead). A bullet (in contrast to a shell) does not contain explosives, and damages the intended target solely by imparting kinetic energy upon impact. Modern bullets for firearms are generally part of a cartridge, also known as a round. In contrast, bullets for air guns are not part of a cartridge. The word "bullet" is sometimes used to refer to the grouping of bullet, case, gunpowder and primer more properly known as a cartridge or round.; the Oxford English Dictionary definition of a bullet is "a projectile of lead ... for firing from a rifle, revolver etc."

Monday, December 17, 2007

JAR Files

A JAR file has a manifest file situated in the path META-INF/MANIFEST.MF. The entries in the manifest file conclude how the JAR file will be used. JAR files which are intended to be executed as separate programs will have one of their classes specified as the "main" class. The obvious file would have an entry such as

Main-Class: myPrograms.MyClass

Such JAR files are characteristically started with a command similar to

java -jar foo.jar

These files can also include a Classpath entry, which identifies other JAR files to be overloaded with the JAR. This entry consists of a list of absolute or relation paths to other JAR files. Although intended to simplify JAR use, in practice, it turns out to be infamously brittle as it depends on all the relevant JARs being in the exact locations specified when the entry-point JAR was built. To change versions or locations of libraries, a new manifest is required.

Wednesday, December 12, 2007

JAR

In computing, a JAR file (or Java ARchive) file used to deal out a set of Java classes. It is used to store compiled Java classes and connected metadata that can constitute a program.

* WAR (file format) (Web Application aRchive) files are also Java archives which store XML files, java classes, Java Server Pages and extra objects for Web Applications.

* EAR (file format) (Enterprise ARchive) files are also Java archives which store XML files, java classes and additional objects for Enterprise Applications.

* RAR (file format) (Resource Adapter aRchive) files are also Java archives which store XML files, java classes and added objects for J2EE Connector Architecture (JCA) applications.

JAR files can be created and extracted by the "jar" command that comes with the JDK. It can be done using zip tools, but as WinZip has a custom of renaming all-uppercase directories and files in lower case, this can raise support calls with whoever shaped the JAR or the tool authors themselves. WinRAR, on the additional hand, retains the original case of filenames.

Tuesday, December 4, 2007

Grape

A grape is the non-climacteric fruit that grows on the permanent and deciduous woody vines of the folks Vitaceae. Grapes develop up in clusters of 6 to 300, and can be black, blue, golden, green, purple, red, pink, brown, peach or white. They can be eaten raw or used for producting jam, grape juice, jelly, wine and grape germ oil. Development of grapevines occurs in vineyards, and is called viticulture. One who studies and practises increasing grapes for wine is called a viticulturist. The leaves of the grape vine itself are painstaking safe to eat and are used in the production of dolmades.

Monday, November 26, 2007

Lighthouse of Alexandria

The Pharos of Alexandria was a large tower built in the 3rd century BC (between 285 and 247 BC) on the island of Pharos in Alexandria, Egypt to give out as that port's landmark, and later, its lighthouse.

With a height variously expected at between 115 and 150 meters (383 - 450 ft) it was among the tallest man-made structures on Earth for many centuries, and was recognized as one of the Seven Wonders of the World by Antipater of Sidon. It was the third big and tallest building after the two Great Pyramids (of Khufu and Khafra) for its whole life. Some scientists calculate approximately a much taller height exceeding 180 metres that would make the tower the tallest building up to the 14th century.

Monday, November 19, 2007

Traffic Claming

Traffic calming is a set of strategies used by urban planners and traffic engineers which aims to slow down traffic and get better safety for pedestrians and bicyclists, although some of these features can also be hazardous to cyclists. It is now comparatively common in Europe, especially Northern Europe; less so in North America.Traffic calming has conventionally been justified on the grounds of pedestrian safety and reduction of noise and local air pollution which are side effects of the traffic. However, it has become more and more apparent that streets have many social and recreational functions which are severely impaired by fast car traffic. For much of the twentieth century, streets were designed by engineers who were charged only with ensuring traffic flow and not with development other functions of streets. The rationale for traffic reassuring is now broadening to include designing for these functions.