IMT-2000

International Mobile Telecom System - 2000, the third generation Mobile communication System the earliest in 1985 by the International telecommunication union (ITU) was put forward, it was known then as future public land Mobile communication System (FPLMTS), 1996 was renamed IMT - 2000 (International Mobile communications - 2000), which means that the System work in 2000MHz frequencies, the highest business rate can reach 2000kb/s, expected in around the year 2000 get commercial. Since 1997, due to the second generation mobile communication system of huge success, users of high-speed growth and limited system capacity and limited the contradiction between the business gradually obvious, the third generation mobile communication standardization work since 1997 enters the essence and stage.

classification

After detailed technical evaluation, analysis, and lots of coordination and fusion after work, in May 2000 itu-t R 2000 session (RA - 2000) approval, passed IMT - 2000 wireless interface specifications (RSPC) suggestion, it is divided into two types of CDMA and TDMA five technologies.

Three kinds of CDMA technology

Among them main technology for the following three CDMA technology:

Website Optimization

introduction

Website optimization is to perform site procedures and contents, edition piece, arrangement of optimizing adjustment, to make your site is more easy to search engine indexed, enhance the user experience (UE) and conversion and create value.

Website optimization can narrow and generalized from two aspects that narrow site optimization, namely, search engine optimization, is also search the Internet station design suits when searching engines, satisfy your search engine ranking in the search engine index, thus retrieval gain ahead, enhance the search engine marketing effect. The generalized website optimization the factor considered not only is the search engine, also including fully satisfy the demand of users characteristics, clear site navigation, perfect online help etc, and based on this, make web function and information play the best effect. Also is to enterprise's websites as the foundation, and Internet service providers (such as search engines, etc.), partners and customers, suppliers, vendors and other network marketing environment factors to establish good relationship.

Hurdles run knowledge ABC

Hurdles run began in England. The 17th and 18th centuries, British shepherd often across the pen and the game gradually evolved into hurdles run. Become athletics project for 10 0 years history.

The earliest hurdles running tournaments appeared in 1860. In 1864, a famous British Oxford and Cambridge two universities in the first tournament, put the official games. As the hurdles Distance for 12 size-zero, $109. 73 meters. Cambridge player Daniel with 17 seconds 7 grades pioneering 120 yards gaolan game records.

In 1896 1 Olympic Games held in the men's 100m hurdles running tournaments, column high 1 meter, column number 8 fighter. Because pass column technology is poor, champion grades for 17 seconds. 6.

Hurdles run really get development and formation of technical style is in the United States. 19 century, the United States athletes grams of lenze global reinhard perfected the straight before cross and single arm leading technology, later became modern hurdles technology foundation. Therefore, he was called "the father of the modern hurdles movement". In 1900 Olympics he obtained 110 meters and 200 meters column gold MEDALS.

Race Walking

Walking from daily walk on the basis of the development of sports, rules out support legs must unbend, from single-support transition to the feet, swinging leg support at the heel contacts to front, after kick the bucket tiptoe may leave the ground to make sure no appear "post-flight" phenomenon, and this is also the main walking and running respectively.

Walking history

Walking originated in the United Kingdom, 1867, Britain held the first walking championships. The 19th century in the 1990s, the sport in Germany prevalence up. In 1893 at Vienna to Berlin, the entire game for 578 park-like kilometres. In 1908, Olympic Games official will racewalking listed as the project. Since 1961, held annual Lou Enoch cup game, caleb walking after development becomes the World Cup of male athletes competing for Lou Enoch cup, caleb female athletes compete for love si fort grace cup race walking first appeared in 1775 and 1800 years of British, some is the clock for .

Digital signature

Digital signature (also called public-key digital signature, electronic signature) is a kind of similar written on paper of ordinary physical signature, but use public-key encryption technology realization, the method used to identify the digital information. A digital signature usually define two complementary operations, one for signatures, another for the verification.

Basic introduction

Digital signature does not refer to put your signature scanning into digital images, or use touchpad acquired signature, more not your inscribe.

Digital signature files are easy to verify the integrity of the (don't need QiFeng chapter, QiFeng signature, also do not need the handwriting expert), and digital signature is can't deny sex (don't need handwriting expert to validation).

Base Station

Base station namely public mobile base is a form of radio stations, it is to point to in certain radio covering area, through the mobile communication exchange centre, and mobile telephone terminal of information between relay radio transceivers letter station.

Basic definition

The generalized base station, is the abbreviation of base station subsystem. With the GSM network as an example, including base station transceiver letter machine (BTS) and base station controller (BSC). A base station controller can control dozen that dozens of base station transceiver letter machine. While in WCDMA system, similar concept called NodeB and RNC.

Sumo

Sumo, called grain dance, originated in China of han dynasty, by two strongman bare the upper part of the body, mutual wrestling. Until the seventh century A.D.), in the funeral objects (from emperor these 13 years), China sent envoys to Japan show grain dance regards, regarded as the first introduced into Japan, sumo to Japan original sumo cause certain effect. Later became the kingdom of Japanese technology, Japan's international combatives and sports. As a professional athletics project, in Japan, called big sumo.

history

China and Japan have sumo in history. From some unearthed relics look, Chinese dynasties horn against image with Japanese popular now sumo very similar. The latest in early dynasty, China had sumo name. Tang, some in each generation, sumo activity has been rife. To the middle qing dynasty, sumo name it gradually disappear. Modern, sumo has been regarded as Japan's more, in fact, sumo original in ancient China "Angle worth" one kind. Early in the western han dynasty, JiZhou (now hebei) area popular with a kind of folk game: people wore masks with horns, dou force ratio each other. This is competitive and performing activities, be called "Angle worth", also known as the "chiyou play. Sima qian in shi-ji huangdi was recorded in this book," chiyou's head with horn, and huangdi head, to Angle, this JiZhou arrive for chiyou theatre. "Will" Angle worth "and huangdi war chiyou legend link, this is enough explains it of the long history.