The use of light as a communication media used in China Great Wall distance more than 7300 km with in 1 hour to sent signal from one tower to another. In the late 20th century optical communication took back in to the seat for its advantages over coaxial transport and other electrical communication system. In 1966, Kaw and Hockman proposed the idea of using optical fiber light wave communication and their prediction was data loss 20dB/km [12]. In late 1980s to 1990s, coherent detection communication systems were introduced to enhance the transmission system. However, optical system needs still regeneration over long distance. By early 1990s, the system channel capacity boosted and reached to 10Gb/s but in 2003 it reached up to 40Gb/s via support WDM system. Recently, some experiments have done to transmit data 21.7 Tb/s though crossing the 10Tb/s per fiber barrier and it is new challenges for optical communication to innovate novel schemes of optical amplification, modulation technique or Fiber channel design.
2.2 Coherent Optical OFDM
The application of OFDM to optical communications used surprisingly late and relatively compared with RF complement, although the first paper on optical OFDM in the open literature was created by Pan and Green in 1996 and also in this year’s some research was happen. However, the fundamental advantages of OFDM against optical channel dispersion was not recognized in optical communication until 2001, when OFDM to combat model model dispersion in multimode fiber (MMF). A clear understanding of the unique optical channel or optical system make possible the most efficient design of the CO-OFDM system. Coherent optical OFDM (CO-OFDM) represents the ultimate performance in receiver performance, sp...
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... of dispersion management in optical transmission, which are Direct Detection optical OFDM (DDO-OFDM) and Coherent Optical OFDM (CO-OFDM). According to the performance in spectral efficiency, receiver sensitivity and polarization dispersion, CO-OFDM is better performance but more complexes to implement then DDO-OFDM. CO-OFDM has emerged for 100 GB/s transmission over 1000km SSMF. However , at this data rates, the signal quality is significantly interrupted mainly due to the impact of PMD, CD and intra channel nonlinearity effect but using Coded OFDM and efficient modulation technique we will try to improve error free data rata and intra channel nonlinearity of fiber. The choice of different digital modulation method directly affect to OSNR, [7] Optical fiber dispersion, nonlinear effect, bandwidth efficiency and BER which can effect as a whole system performance.
My first reason why it was not worth the costs is the wall actually did not keep people out. It was not very protective. The wall affected so many things. It affected life styles, people's daily routine. It also affected families. (Doc. E). The wall was not one big long wall. It stretched three hundred miles to the west and there was a watchtower beyond the wall end. But there were still places that were not protected by the wall. The Xiongnu could just walk around the wall and them come in and invade. People may think that they are fine because the wall is protecting them but they need to be aware that there are spots that are not protected by the wall. They would spend so much money on this wall to protect people when it really does not protect them that well (Doc. D). One of the most important reasons is that they had to pay the Xiongnu to stay out and not invade them. They paid them with Silk Thread and Silk Fabric. The amount they gave them from the year 51 BCE to one BCE they almost tripled the amount! It increased a lot. If they had to pay them to stay out them that proves that the Great Wall does not work.
In the Chinese history there is an important date that many remember. That is the Cultural Revolution that started in 1966 (Chan 103). This Cultural Revolution wasn’t a war by any means, but a competition between the different factions of the communist party for power. The Cultural Revolution was also a very important event in the history of the Chen Village. We saw through the different chapters of Chen Village just how it affected the different people that were living there during the eleven year span that it lasted (Chan 103). The Cultural Revolution caused a lot of problems to stir up in Chen Village.
Through art, people can expose their ideas, their opposition to the government rules and regulations in a quiet way. The artists try to expose their revolutionary ideas and motivate the people to fight against the cruel actions of the government. The concept of Chinese government about art is that it must always serve the people and the government is always ready to promote art by giving systematic education about the new art. They always give preferences to the revolutionary art and the nonrevolutionary arts were banned at that time. There are different levels of artistic concepts in China which include the modern art, religious art, commercial art etc.
The Cultural Revolution was a revolution that had happened between 1966 and 1976 and had a great impact on China. The Cultural Revolution used to be known as the Great Proletarian Cultural Revolution but was changed after many years. The main goal of this Revolution was to preserve true communist mainly in China by purging remnants of capitalist and traditional elements from Chinese society. It was also used to re-impose Maoist which was thought as the dominant ideology within the Party. The Cultural Revolution was basically a sociopolitical movement. But it was mainly for the return of the leader, Mao Zedong, who was the leader of the revolution on and off. Which had led him to a position of power after the Great Leap Forward which paralyzed
Chuen, Master L.K. (1996). Feng Shui Handbook: How to Create a Healthier Living and Working Environment. New York: Henry Holt and Company, Inc.
China is well known for its Great Wall, but it has a history surrounded by the deaths of many Chinese people. The Great Wall of China started being built in 221 to 206 BCE by Emperor Qin, but the Qin were overthrown by the Han Dynasty: 206 to 220 CE. The Qin had built around 1,500 - 2,500 miles of the Great Wall and the Han Dynasty built around 4,000 miles of wall. The Great Wall of China that people know today was later built by the Ming Dynasty 1,500 years later (Doc A). The Great Wall of China required the use of many resources and the deaths of many built up as the project went on, but do the benefits it created outweigh the costs of its construction and then maintaining it? The Great Wall of ancient China’s benefits outweigh the costs: it was a part of a grand plan to achieve peace with the Xiongnu and to let trade prosper with China and the western world so China’s influence would spread and new ideas could enter China.
.... But this wall must be passable; it must have an opening that anyone can pass through. But the only people that will find the door through are the ones that are willing to be open themselves!” There are so many views, ideas, and aspects of wall due to its extreme complexity, culturally and archeologically. Everything can be linked to everything! This is the ultimate anthropological truth. The Great Wall is truly great.
The true benefits of fiber optics become apparent, since it is not affected by electro-magnetic interference (EMI).
The Great Wall of China has been called a wonder by many who have seen it. It brings pride to the Chinese nation, and is known for being the only man made structure visible from space. The magnitude of The Great Wall is an architectural achievement as well as an example of the will power of man. Many find it hard to believe that such an amazing sight could have a history so filled with death, slavery and sadness as The Great Wall does. The Great Wall of China is one of the world's most famous architectural triumphs and has helped China throughout its history, even though its creation is marked by tragedy.
China has an area of 9.6 million square kilometers and a coastline of 18,000 kilometers (Network Center of MOFCOM, 2004). It has a population of 1,401,586,609 people as of 2015 (Worldometers, 2015). In China they tend to eat a lot of the same foods. Some of the local food consists of rice, noodles, fish, vegetables and meats (Parkinson, 2011). “China is described as a collectivist country because it “emphasizes the needs and goals of the group as a whole over the needs and wishes of each individual ().” “Upholding a stable and harmonious society has been viewed as the most important role of ethics (Werth, 2013).”
The Great Proletarian Cultural Revolution, beginning as a campaign targeted at removing Chairman Mao Zedong's political opponents, was a time when practically every aspect of Chinese society was in pandemonium. From 1966 through 1969, Mao encouraged revolutionary committees, including the red guards, to take power from the Chinese Communist party authorities of the state. The Red Guards, the majority being young adults, rose up against their teachers, parents, and neighbors. Following Mao and his ideas, The Red Guard's main goal was to eliminate all remnants of the old culture in China. They were the 'frontline implementers' who produced havoc, used bloody force, punished supposed 'counter revolutionists', and overthrew government officials, all in order to support their 'beloved leader'.
The Great Wall of China stretches about 5,500 miles long crossing deserts, mountains, grasslands, and plateaus. It took more than 2,000 years to build this incredible manmade structure. Many people died to build this wall. It displays the changes between the agricultural and nomadic civilizations. It proves that the superb structure was very important to military defense. It became a national symbol of the Chinese as a security for their country and its people. The Great Wall of China must be preserved at all cost because it is a historical symbol that made it possible for China and other nations across the world to prosper (UNESCO World Heritage Centre: The Great Wall).
Fiber optic technology has opened the door to many more communication opportunities for the world today. It provides higher fidelity long distance telephone conversations, as well as secure communication systems. Today, more than 90% of the United States long-distance traffic is already carried over optical fiber; more than 15 million miles have been installed, virtually all of it using the original design.
Fiber optics is a new technology that uses rays of light instead of electricity to transmit information over optical fibers at very high speeds. The optical fibers are usually thin strands of glass that are combined into cables and used to send information and computer data in the form of pulses of light. The optical fibers provide much clearer transmission than conventional copper cable and satellite links. The world market for optical fiber continues to grow rapidly, with shipments increasing 14 percent from an estimated 7.0 million kilometers of fiber in 1990 to approximately 8.0 million in 1991. The demand for multimode fiber is predicted to continue to expand through the mid-1990s, with some market analysts indicating that 15 to 20 percent annual growth over the next three years is reasonable. Strong demand is expected for singlemode and multimode fiber to be used in cables for local area networks, telecommunications, cable television (CATV), and transoceanic fiber-optic systems.