The plastic provides little bullet-resistance. Glass, much harder than plastic, flattens the bullet. The plastic deforms, absorbing energy and (perhaps) stopping the bullet. The ability of the plastic layer to stop projectiles is directly proportional to its thickness. Bulletproof glass may be up to three inches thick.
All the parts of the glass must be transparent. The essential components are these:
The most usual method today requires three parts in layers:
A simpler version is used for car windshields. It consists of two panels of toughened glass, bonded together with polyvinyl butyal (PVB). The PVB stops cracks in the outer glass from spreading.
The idea is for guards inside to be able to shoot out, while attackers can't shoot in. One-way bulletproof glass is usually made of only two layers, a brittle layer on the outside and a flexible one on the inside. A bullet fired from the outside hits the brittle layer first, shattering an area of it. This absorbs some of the bullet's kinetic energy, and spreads it on a larger area. When the slowed bullet hits the flexible layer, it is stopped.
However, when a bullet is fired from the inside, it hits the flexible layer first. The bullet penetrates the flexible layer because its energy is focused on a smaller area; the brittle layer then shatters outward due to the flexing of the inner layer and does not significantly hinder the bullet's progress. A problem with this idea is that a two-layer glass has limited stopping power.
There is a new type of transparent armour with aluminium oxynitride instead of glass. As the outside 'strike plate' layer, it is much lighter and performs better than traditional glass/polymer laminates. Aluminum oxynitride 'glass' can defeat .50 caliber armour-piercing rounds. Various types of other materials which closely resemble glass are also being developed.
Certain types of ceramic can also be used for "transparent" armour. They are denser and harder than traditional glass. These new types of transparent ceramic armours make thinner armour with equal stopping power to traditional laminated glass.
Digital certificates
Digital certificates are electronic 'credit cards' that establish your credentials when doing business or other transactions on the Web. It is issued by a certification authority (CA). It contains your name, a serial number, expiration dates, a copy of the certificate holder's public key (used for encrypting messages and digital signatures), and the digital signature of the certificate-issuing authority so that a recipient can verify that the certificate is real. Some digital certificates conform to a standard, X.509. Digital certificates can be kept in registries so that authenticating users can look up other users' public keys.
Classes of digital certificate:
• The class 1 defines the certificate that do not hold any legal validity as the validation process is based only on a valid email ID and involves no direct verification.
•The class 2 category states that a person's identity is to be verified against a trusted,pre-verified database.
•The class 3 requires the person present himself or herself in front of the registration authority and prove his or her identity.Date Masamune
In the Edo period, the Date clan were identified as one of the "tozama" or outsider clans, in contrast with the "fudai" or insider "daimyō" clans which were hereditary vassals or allies of the Tokugawa clan.
Date sent troops which fought with the Tokugawa during the Battle of Sekigahara.
The feudal daimyō were sometimes identified with the suffix ""-kō"" (servant) combined with the name of a place or a castle.
In 1601, Date built the Sendai castle; and the modern-day city of Sendai developed around it. Sendai"-kō" was one of the ways Date Masamune was described.
In 1613-1620, Date send Hasekura Tsunenaga on a diplomatic mission to the courts of Philip III of Spain in Madrid and Pope Paul V in Rome.
This historic visit is called the .
In 1991, a minor planet or main-belt asteroid 6859 Datemasamune was named after this Edo period historical figure.
Laura Feiersinger
Laura Feiersinger (born 5 April 1990 in Saalfelden, Austria) is an Austrian football player. She plays for FC Bayern München as a striker. Her father, Wolfgang Feiersinger, was a player for Borussia Dortmund and the Austrian national football team.
She started playing football for the SV Oftering. From 2001 till 2008 she played for 1. SK Saalfelden and later vor FC Pinzgau Saalfelden, a club coming out of the fusion between 1. Saalfeldner SK und ESV Saalfelden, the second club in Saalfelden. 2008 she went to USK Hof, the champion of the 2nd league west and played in the play off matches versus SV Groß-Schweinbarth. Together with Hof she was promoted to the ÖFB Frauenliga.
In 2010 she went to Germany and joined Herforder SV, which was, in this season, promoted to the Bundesliga. 2011/12 she went to FC Bayern München and debuted on 21 August 2011 versus Bayer Leverkusen.
Laura Feiersinger played for the Austrian U17 and U19 team and since 2010 in the Austrian women football national team.
The article uses information from de.wikipedia.org.
Quadruped
A quadruped is a vertebrate which walks on four legs. This is the basic locomotion of amphibia, reptiles and mammals. Those which walk on two legs or those which fly have evolved from the basic pattern. The scientific term for quadrupeds is Tetrapoda.
Pope Alexander
Pope Alexander may mean:
Patrick Murphy
Patrick Murphy may mean
Frank Drake
Frank Donald Drake PhD is an American astronomer (a scientist who studies the universe and what is inside it) and astrophysicist (someone who studies the physics of astronomy). He is most famous for joining in the first new SETI (Search for ExtraTerrestrial Intelligence) experiment in 1960 and for making the Drake equation.
Born on the 28th of May 1930 in Chicago to Richard and Winifred Drake. As a young boy (in Chicago), Drake loved electronics and chemistry. He says that he thought of life on other planets but never said the idea with his family or teachers.
He enrolled at Cornell University on a Navy Reserve Officer Training Corps scholarship. Once there, he began studying astronomy. A lecture from astrophysist Otto Struve in 1951 strengthen Drake's ideas about the possibility of extraterrestrial life. After college, he served briefly as an electronics officer on the USS Albany. He then went on to graduate school at Harvard in radio astronomy.
Drake's hobbies include lapidary and orchid cultivation.
Drake started his career undertaking radio astronomical research at the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virginia, and for a short time in 1963 at the Jet Propulsion Laboratory. He conducted key measurements which revealed the presence of a Jovian ionosphere and magnetosphere.
In 1960, he started Project Ozma, which searches for extraterrestrial life. Drake is one of the pioneers of the modern field of the search for extraterrestrial intelligence with Giuseppe Cocconi, Philip Morrison, Iosif Shklovsky, and Carl Sagan.
Drake joined the Astronomy faculty of Cornell University in 1963. Drake lead the conversion of the Arecibo Observatory to a radio astronomical facility. He lead Arecibo's improvements in 1974 and 1996. As a researcher, Drake was involved in the early work on pulsars. In this period, Drake was a professor at Cornell University and Director of the National Astronomy and Ionosphere Center (NAIC) – the formal name for the Arecibo facility. In 1974 he wrote the Arecibo message.
Drake co-designed the Pioneer plaque with Carl Sagan in 1972, the first physical message sent into space. The plaque was made to be read by clever alien life if they find it. He later helped the making of the Voyager Golden Record. He was elected to the AAAS in 1974.