A Yagi–Uda antenna known as a Yagi antenna, is a directional antenna consisting of multiple parallel elements in a line half-wave dipoles made of metal rods. Yagi–Uda antennas consist of a single driven element connected to the transmitter or receiver with a transmission line, additional "parasitic elements" which are not connected to the transmitter or receiver: a so-called reflector and one or more directors, it was invented in 1926 by Shintaro Uda of Tohoku Imperial University and Hidetsugu Yagi. The reflector element is longer than the driven dipole, whereas the directors are a little shorter; the parasitic elements absorb and reradiate the radio waves from the driven element with a different phase, modifying the dipole's radiation pattern. The waves from the multiple elements superpose and interfere to enhance radiation in a single direction, achieving a substantial increase in the antenna's gain compared to a simple dipole. Called a "beam antenna", or "parasitic array", the Yagi is widely used as a high-gain antenna on the HF, VHF and UHF bands.
It has moderate to high gain which depends on the number of elements used limited to about 20 dBi, linear polarization, unidirectional beam pattern with high front-to-back ratio of up to 20 db. and is lightweight and simple to construct. The bandwidth of a Yagi antenna, the frequency range over which it has high gain, is narrow, a few percent of the center frequency, decreases with increasing gain, so it is used in fixed-frequency applications; the largest and best-known use is as rooftop terrestrial television antennas, but it is used for point-to-point fixed communication links, in radar antennas, for long distance shortwave communication by shortwave broadcasting stations and radio amateurs. The antenna was invented in 1926 by Shintaro Uda of Tohoku Imperial University, with a lesser role played by his colleague Hidetsugu Yagi; however the "Yagi" name has become more familiar with the name of Uda omitted. This appears to have been due to Yagi filing a patent on the idea in Japan without Uda's name in it, transferring the patent to the Marconi Company in the UK.
Yagi antennas were first used during World War II in radar systems by the Japanese, British and US. After the war they saw extensive development as home television antennas; the Yagi–Uda antenna consists of a number of parallel thin rod elements in a line half-wave long supported on a perpendicular crossbar or "boom" along their centers. There is a single driven element driven in the center, a variable number of parasitic elements, a single reflector on one side and optionally one or more directors on the other side; the parasitic elements are not electrically connected to the transmitter or receiver, serve as passive radiators, reradiating the radio waves to modify the radiation pattern. Typical spacings between elements vary from about 1⁄10 to ¼ of a wavelength, depending on the specific design; the directors are shorter than the driven element, while the reflector are longer. The radiation pattern is unidirectional, with the main lobe along the axis perpendicular to the elements in the plane of the elements, off the end with the directors.
Conveniently, the dipole parasitic elements have a node at their centre, so they can be attached to a conductive metal support at that point without need of insulation, without disturbing their electrical operation. They are bolted or welded to the antenna's central support boom; the driven element is fed at centre so its two halves must be insulated where the boom supports them. The gain increases with the number of parasitic elements used. Only one reflector is used since the improvement of gain with additional reflectors is negligible, but Yagis have been built with up to 30–40 directors; the bandwidth of the antenna is the frequency range between the frequencies at which the gain drops 3 dB below its maximum. The Yagi–Uda array in its basic form has narrow bandwidth, 2–3 percent of the centre frequency. There is a tradeoff between gain and bandwidth, with the bandwidth narrowing as more elements are used. For applications that require wider bandwidths, such as terrestrial television, Yagi–Uda antennas feature trigonal reflectors, larger diameter conductors, in order to cover the relevant portions of the VHF and UHF bands.
Wider bandwidth can be achieved by the use of "traps", as described below. Yagi–Uda antennas used for amateur radio are sometimes designed to operate on multiple bands; these elaborate designs create electrical breaks along each element at which point a parallel LC circuit is inserted. This so-called trap has the effect of truncating the element at the higher frequency band, making it a half wavelength in length. At the lower frequency, the entire element is close to half-wave resonance, implementing a different Yagi–Uda antenna. Using a second set of traps, a "triband" antenna can be resonant at three different bands. Given the associated costs of erecting an antenna and rotor system above a tower, the combination of antennas for three amateur bands in one unit is a practical solution; the use of traps is not without disadvantages, however, as they reduce the bandwidth of the antenna on the individual bands and reduce the antenna's electrical efficiency and subject the antenna to additional mechanical considerations.
Consider a Yagi–Uda consisting of a reflect
September 11 attacks
The September 11 attacks were a series of four coordinated terrorist attacks by the Islamic terrorist group al-Qaeda against the United States on the morning of Tuesday, September 11, 2001. The attacks killed 2,996 people, injured over 6,000 others, caused at least $10 billion in infrastructure and property damage. Additional people died of 9/11-related cancer and respiratory diseases in the months and years following the attacks. Four passenger airliners operated by two major U. S. passenger air carriers —all of which departed from airports in the northeastern United States bound for California—were hijacked by 19 al-Qaeda terrorists. Two of the planes, American Airlines Flight 11 and United Airlines Flight 175, were crashed into the North and South towers of the World Trade Center complex in Lower Manhattan. Within an hour and 42 minutes, both 110-story towers collapsed. Debris and the resulting fires caused a partial or complete collapse of all other buildings in the World Trade Center complex, including the 47-story 7 World Trade Center tower, as well as significant damage to ten other large surrounding structures.
A third plane, American Airlines Flight 77, was crashed into the Pentagon in Arlington County, which led to a partial collapse of the building's west side. The fourth plane, United Airlines Flight 93, was flown toward Washington, D. C. but crashed into a field in Stonycreek Township near Shanksville, after its passengers thwarted the hijackers. 9/11 is the single deadliest terrorist attack in human history and the single deadliest incident for firefighters and law enforcement officers in the history of the United States, with 343 and 72 killed, respectively. Suspicion fell on al-Qaeda; the United States responded by launching the War on Terror and invaded Afghanistan to depose the Taliban, which had failed to comply with U. S. demands to extradite Osama bin expel al-Qaeda from Afghanistan. Many countries strengthened their anti-terrorism legislation and expanded the powers of law enforcement and intelligence agencies to prevent terrorist attacks. Although Osama bin Laden, al-Qaeda's leader denied any involvement, in 2004 he claimed responsibility for the attacks.
Al-Qaeda and bin Laden cited U. S. support of Israel, the presence of U. S. troops in Saudi Arabia, sanctions against Iraq as motives. After evading capture for a decade, bin Laden was located in Pakistan and killed by SEAL Team Six of the U. S. Navy in May 2011; the destruction of the World Trade Center and nearby infrastructure harmed the economy of Lower Manhattan and had a significant effect on global markets, which resulted in the closing of Wall Street until September 17 and the civilian airspace in the U. S. and Canada until September 13. Many closings and cancellations followed, out of respect or fear of further attacks. Cleanup of the World Trade Center site was completed in May 2002, the Pentagon was repaired within a year. On November 18, 2006, construction of One World Trade Center began at the World Trade Center site; the building was opened on November 3, 2014. Numerous memorials have been constructed, including the National September 11 Memorial & Museum in New York City, the Pentagon Memorial in Arlington County and the Flight 93 National Memorial in a field in Stonycreek Township near Shanksville, Pennsylvania.
Although not confirmed, there is evidence of alleged Saudi Arabian involvement in the attacks. Given as main evidence in these charges are the contents of the 28 redacted pages of the December 2002 Joint Inquiry into Intelligence Community Activities before and after the Terrorist Attacks of September 11, 2001 conducted by the Senate Select Committee on Intelligence and the House Permanent Select Committee on Intelligence; these 28 pages contain information regarding the material and financial assistance given to the hijackers and their affiliates leading up to the attacks by the Saudi Arabian government. The origins of al-Qaeda can be traced to 1979. Osama bin Laden helped organize Arab mujahideen to resist the Soviets. Under the guidance of Ayman al-Zawahiri, bin Laden became more radical. In 1996, bin Laden issued his first fatwā. In a second fatwā in 1998, bin Laden outlined his objections to American foreign policy with respect to Israel, as well as the continued presence of American troops in Saudi Arabia after the Gulf War.
Bin Laden used Islamic texts to exhort Muslims to attack Americans until the stated grievances are reversed. Muslim legal scholars "have throughout Islamic history unanimously agreed that the jihad is an individual duty if the enemy destroys the Muslim countries", according to bin Laden. Bin Laden orchestrated the attacks and denied involvement but recanted his false statements. Al Jazeera broadcast a statement by bin Laden on September 16, 2001, stating, "I stress that I have not carried out this act, which appears to have been carried out by individuals with their own motivation." In November 2001, U. S. forces recovered a videotape from a destroyed house in Afghanistan. In the video, bin Laden admits foreknowledge of the attacks. On December 27, 2001, a second bin Laden video was released. In the video, he said: It has become clear that the West in general and America in particular have an unspeakable hatred for Islam.... It is the hatred of crusaders. Terrorism against America deserves to be praised because it was a response to injustice, aimed at forcing America to stop its support for Israel, which kills our people....
Ministry of Education, Culture, Sports, Science and Technology
The Ministry of Education, Sports and Technology known as MEXT, Monka-shō, is one of the ministries of the Japanese government. The Meiji government created the first Ministry of Education in 1871. In January 2001, the former Ministry of Education, Science and Culture and the former Science and Technology Agency merged to become the present MEXT. MEXT is led by the Minister of Education, Sports and Technology, a member of the Cabinet and is chosen by the Prime Minister from the members of the Diet; the Japanese government centralises education, it is managed by a state bureaucracy that regulates every aspect of the education process. The School Education Law requires schools around the country to use textbooks that follow the curriculum guideline set by the ministry, although there are some exceptions. MEXT is one of three ministries, it offers the Monbukagakusho Scholarship known as the MEXT or Monbu-shō scholarship. The Ministry sets standards for the romanization of Japanese. MEXT provides the Children Living Abroad and Returnees Internet which provides information to Japanese families living abroad.
MEXT sends teachers around the world to serve in nihonjin gakkō, full-time Japanese international schools in foreign countries. The Japanese government sends full-time teachers to hoshū jugyō kō supplementary schools that offer lessons that are similar to those of nihonjin gakkō or those which each have student bodies of 100 students or greater. In addition, MEXT subsidizes weekend schools. National Spiritual Mobilization Movement Education in Japan Fundamental Law of Education History of education in Japan Japanese history textbook controversies Monbukagakusho Scholarship Reischauer, Edwin O. and Marius Jansen. The Japanese Today. Tokyo: Tuttle Publishing. Official website Official website Ministry of Education, Science and Culture website Ministry of Education, Science and Culture website Press release on Legislation of "the National University Corporation Law"
Education in Japan
Education in Japan is compulsory at the elementary and lower secondary levels. Most students attend public schools through the lower secondary level, but private education is popular at the upper secondary and university levels. Education prior to elementary school is provided at day-care centers. Public and private day-care centers take children from under age 1 on up to 5 years old; the programmes for those children aged 3–5 resemble those at kindergartens. The educational approach at kindergartens varies from unstructured environments that emphasize play to structured environments that are focused on having the child pass the entrance exam at a private elementary school; the academic year starts from April and ends in March, having summer vacation in August and winter vacation in the end of December to the beginning of January. There are few days of holidays between academic years; the period of academic year is the same all through elementary level to higher educations nationwide. Japanese students rank among OECD students in terms of quality and performance in reading literacy and sciences.
The average student scored 540 in reading literacy and science in the OECD’s Programme for International Student Assessment and the country has one of the world's highest-educated labour forces among OECD countries. Its populace is well educated and its society values education as a platform for social mobility and for gaining employment in the country's high-tech economy; the country's large pool of educated and skilled individuals is responsible for ushering Japan’s post-war economic growth. Tertiary-educated adults in Japan graduates in sciences and engineering, benefit economically and from their education and skills in the country's high tech economy. Spending on education as a proportion of GDP is below the OECD average. Although expenditure per student is comparatively high in Japan, total expenditure relative to GDP remains small. In 2015, Japan’s public spending on education amounted to just 3.5 percent of its GDP, below the OECD average of 4.7%. In 2014, the country ranked fourth for the percentage of 25- to 64-year-olds that have attained tertiary education with 48 percent.
In addition, bachelor's degrees are held by 59 percent of Japanese aged 25–34, the second most in the OECD after South Korea. As the Japanese economy is scientific and technological based, the labor market demands people who have achieved some form of higher education related to science and engineering in order to gain a competitive edge when searching for employment opportunities. About 75.9 percent of high school graduates attended a university, junior college, trade school, or other higher education institution. Japan's education system played a central part in Japan's recovery and rapid economic growth in the decades following the end of World War II. After World War II, the Fundamental Law of Education and the School Education Law were enacted; the latter law defined the school system that would be in effect for many decades: six years of elementary school, three years of junior high school, three years of high school, two or four years of university. Although Japan ranks on the PISA tests, its educational system has been criticized in the US for its focus on standardized testing and conformity.
Formal education in Japan began in the 6th century. Buddhist and Confucian teachings as well as sciences, calligraphy and literature were taught at the courts of Asuka and Heian. Scholar officials were chosen through an Imperial examination system, but contrary to China, the system never took hold and titles and posts at the court remained hereditary family possessions. The rise of the bushi, the military class, during the Kamakura period ended the influence of scholar officials, but Buddhist monasteries remained influential centers of learning. In the Edo period, the Yushima Seidō in Edo was the chief educational institution of the state. Under the Tokugawa shogunate, the daimyō vied for power in the pacified country. Since their influence could not be raised through war, they competed on the economic field, their warrior-turned-bureaucrat Samurai elite had to be educated not only in military strategy and the martial arts, but agriculture and accounting. The wealthy merchant class needed education for their daily business, their wealth allowed them to be patrons of arts and science.
But temple schools educated peasants too, it is estimated that at the end of the Edo period 50% of the male and 20% of the female population possessed some degree of literacy. Though contact with foreign countries was restricted, books from China and Europe were eagerly imported and Rangaku became a popular area of scholarly interest. There were facilities that were created to educate samurai and their children to perpetuate morality and mindfulness of their class; these schools, hanko schools, were where scholars would bring together samurai to listen to lectures on Confucianism, military arts, other subjects. Samurai would attempt to teach villagers what they had learned, “proper guidance to the common people’s spirit and manners,” by posting flyers and creating handbooks, Some Shōgun and Daimyō were interested in spreading education throughout their protected land with the target audience as adult commoners and children. Elementary education was imparted as well as morality lessons; the Shirakawa Village School's town bulleti
Yūzō Saeki was a Japanese painter, noted for his work in developing modernism and Fauvist Expressionism within the yōga art movement in early twentieth-century Japanese painting. Saeki was born in Osaka as the son of a Buddhist priest, he was interested in art from an early age, imitated the Impressionist style Kuroda Seiki while learning art in middle school. He moved to Koishikawa in 1917 to study art under Takeji Fujishima and enrolled in the western art department of the Tokyo School of Fine Arts in 1918, he married fellow painter Yoneko Ikeda in 1921. In the summer of 1924, Saeki moved to France with his daughter, he attended the Académie de la Grande Chaumière in Paris, where fellow Japanese painter Katsuzo Satomi introduced him to the Fauvist painter and journalist Maurice de Vlaminck, critical of his work, whose comments influenced his technique. Saeki favored portraiture and landscape paintings of Parisian city scenes the backstreets and buildings in the style of Maurice Utrillo or Vincent van Gogh.
In 1925, two of his works were accepted by the Salon d’Automne. Saeki returned to Japan in 1926 at the urging of his family and formed an artists' society called "1930-nen Kyokai" together with Satomi and other artists returning from France; the same year, he won the Nika prize at the 13th Nikaten, an exhibition held by The Second Society in opposition to the more conservative, government- sponsored Bunten exhibition. However, Saeki could not find inspiration in the suburbs of Tokyo, in August 1927, traveling via the Trans-Siberian Railway, he returned to France. Despite his worsening health, he painted outdoors in inclement weather, his frenetic efforts at depicting the streets of Paris led to a deterioration in the tuberculosis he had long suffered from. By March 1928, he was bedridden, he had a nervous breakdown, died destitute in a mental hospital in the Paris suburbs. An overview of Saeki's life, along with copies of his works, are on display at the renovated Yuzo Saeki Atelier Memorial Hall, on the outskirts of Shinjuku-ku in Tokyo.
Brinbaum Phyliss. Glory in a Line: A Life of Foujita—the Artist Caught Between East and West. Faber & Faber. ISBN 0-571-21179-8 pages 103-106 Yuzo Saeki's World, official Osaka City Museum web site.
Midori Matsushima is a Japanese politician. Her official name is Midori Baba, she is a politician of the Liberal Democratic Party, a member of the House of Representatives in the Diet. A native of Hyogo Prefecture and graduate of the University of Tokyo, she worked at the national newspaper Asahi Shimbun from 1980 to 1995, she was elected to the House of Representatives for the first time in 2000 after an unsuccessful run in 1996. 政治家情報 〜松島 みどり〜. ザ･選挙. JANJAN. Archived from the original on 2007-12-03. Retrieved 2007-10-13. Official website in Japanese
Hisaya Morishige was a Japanese actor and comedian. Born in Hirakata, Osaka, he graduated from Kitano Middle School, attended Waseda University, he began his career as a stage actor became an announcer for NHK, working in Manchukuo. He became famous in films first for comedy roles, appearing in series such as the "Company President" and "Station Front" series, produced by Toho, he appeared in both contemporary and jidaigeki. He was famous on stage playing Tevye in the Japanese version of Fiddler on the Roof, he appeared in television series and specials, was the first guest on the television talk show Tetsuko's Room in 1975. He was long-time head of the Japan Actors Union. Among many honors, Morishige received the Order of Culture from the Emperor of Japan in 1991. Hisaya Morishige died of natural causes at a hospital in Tokyo at 8:16 A. M. on November 10, 2009, at the age of 96. Shiretoko Ryojō, a song about the Shiretoko Peninsula Morishige, Hisaya. Morishige Jiden. Chuo Koron Shinsha. ISBN 978-4122041844.
Medal with Purple Ribbon Person of Cultural Merit Order of the Precious Crown, 2nd Class, Peony Order of Culture People's Honour Award Junior Third Rank Hisaya Morishige on IMDb Hisaya Morishige at the Japanese Movie Database