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Lovell Telescope

The Lovell Telescope is a radio telescope at Jodrell Bank Observatory, near Goostrey, Cheshire in the north-west of England. When construction was finished in 1957, the telescope was the largest steerable dish radio telescope in the world at 76.2 m in diameter. It was known as the "250 ft telescope" or the Radio Telescope at Jodrell Bank, before becoming the Mark I telescope around 1961 when future telescopes were being discussed, it was renamed to the Lovell Telescope in 1987 after Sir Bernard Lovell, became a Grade I listed building in 1988. The telescope forms part of the European VLBI Network arrays of radio telescopes. Both Bernard Lovell and Charles Husband were knighted for their roles in creating the telescope. In September 2006, the telescope won the BBC's online competition to find the UK's greatest "Unsung Landmark". 2007 marked the 50th anniversary of the telescope. If the air is clear enough, the Mark I telescope can be seen from high-rise buildings in Manchester such as the Beetham Tower, from as far away as the Pennines, Winter Hill in Lancashire, Beeston Castle in Cheshire, the Peak District.

It can be seen from south-facing windows of the Terminal 1 restaurant area and departure lounges of Manchester Airport. Bernard Lovell built the Transit Telescope at Jodrell Bank in the late 1940s; this was a 218 ft - diameter radio telescope. Although the Transit Telescope had been designed and constructed by the astronomers that used it, a steerable telescope would need to be professionally designed and constructed; this turned out to be Charles Husband, whom Lovell first met on 8 September 1949. Two circular 15" turret drive gear sets and associated pinions from 15-inch gun turrets were bought cheaply in 1950; the bearings became the two main altitude rotator bearings of the telescope, with the appropriate parts of the telescope being designed around them. Husband presented the first drawings of the proposed giant steerable radio telescope in 1950. After refinements, these plans were detailed in a "Blue Book", presented to the DSIR on 20 March 1951. Construction began on 3 September 1952; the foundations for the telescope were completed on 21 May 1953 after being sunk 90 ft into the ground.

It took until mid-March 1954 to get the double railway lines completed due to their required accuracy. The central pivot was delivered to the site on 11 May 1954, the final bogie in mid-April 1955; the telescope bowl was going to have a wire mesh surface to observe at wavelengths between 1 and 10 meters, so frequencies between 30 and 300 MHz. In February 1954 Lovell and the Air Ministry met to see if funding could be made available for improving the accuracy of the dish so that it could be used on centimetre wavelengths, for research at these wavelengths for the Ministry as well as "other purposes". Although the funding was not made available from the Air Ministry, the planning process had progressed too far and so this improvement was made anyway; the telescope was constructed so that the bowl could be inverted. It was intended to use a movable tower at the base of the telescope to change the receivers at the focus. However, the movable tower was never built, due jointly to funding constraints and the fact that much of the receiver equipment was placed at the base of the telescope rather than at the focus.

Instead, receivers were mounted on 50-foot long steel tubes, which were inserted by a winch into the top of the aerial tower while the bowl was inverted. The cables from the receivers ran down the inside of this tube, which could be connected when the telescope was pointed at the zenith. Associated receiver equipment could be placed either in the small, swinging laboratory directly underneath the surface; the telescope moved for the first time on 3 February 1957: by an inch. It was first moved azimuthally under power on 12 June 1957. By the end of July the dish surface was completed, first light was on 2 August 1957; the telescope was first controlled from the control room on 9 October 1957, by a purpose-built analogue computer. There were large cost overruns with the telescope's construction due to the steeply rising cost of steel at the time the telescope was constructed; the original grant for the telescope's construction came jointly from the Nuffield Foundation and the government. The government increased its share of the funding several times.

The final part of the debt from the construction of the telescope, £50,000, was paid off by Lord Nuffield and the Nuffield Foundation on 25 May 1960, Jodrell Bank observat

Eyal Ben-Ari

Eyal Ben-Ari was a professor of anthropology in the Department of Sociology and Anthropology at the Hebrew University of Jerusalem. His research interests include Japan as well as the Israeli Defence Forces, he served as the head of the university's Harry S. Truman Research Institute for the Advancement of Peace until January 2007, taught the Introduction to Anthropology course, making him well-known to students. Ben-Ari studied sociology and sociology at HUJI, graduating with a B. A. in 1978 and an M. A. in 1980. He received his PhD from the University of Cambridge in 1984 in Social Anthropology, after which he returned to HUJI as a lecturer, senior lecturer, associate professor, full professor, he has served as a visiting professor or research fellow at the University of Wisconsin–Madison's Department of Anthropology and School of Business, the National University of Singapore's Department of Japanese Studies, Sophia University's Faculty of Comparative Culture, Waseda University's Asia-Pacific Research Institute, Kyoto University's Institute for Research in the Humanities.

In 2008, a master's dissertation which he supervised became an object of public controversy due to its thesis that the refusal of Israeli soldiers to rape Arab women was a form of racism. In May 2008, a teaching assistant at Hebrew University published accusations of sexual misconduct regarding one of Ben-Ari's colleagues, which led to closer scrutiny of the department. Ben-Ari's troubles with the law began when a number of students sent an anonymous e-mail to university authorities, accusing him of rape and of threatening to withhold their research funding if they refused to have sex with him. Department chair Zali Gurevitch said that in 2007, another student had mentioned rumours of Ben-Ari's sexual misconduct to him. Ben-Ari was arrested in July 2008 remanded to house arrest and banned from university premises for 30 days pending further investigation. Ben-Ari denied the charges against him, when questioned by police would admit only that he had had a consensual affair with a student 12 years prior.

In August 2008, three female students filed sexual harassment complaints against Ben-Ari. Police announced that they were seeking students willing to file sexual assault complaints against him. However, in September 2008 it was announced. An editorial in Haaretz criticised the media for their sensationalistic reporting of the prurient details of the incident, as compared to the lack of fanfare with which they announced that no charges would be filed. In June 2009, the State Attorney formally closed the case against Ben-Ari due to the statute of limitations. In the aftermath of the incident, HUJI proposed a rule forbidding intimate relations between students and professors. HUJI responded to media inquiries by stating, he had been scheduled to teach at the University of Hong Kong in the fall semester of 2008. Ben-Ari was seen visiting the HUJI campus in December 2008, to the consternation of those who had accused him, he had been scheduled to take up lecturing duties again at HUJI in early 2009, teaching one undergraduate course about family and education in Japan, one graduate course about anthropology in Israel.

By September 2010, Ben-Ari still had not taken up lecturing duties again, though he was acting as an advisor for graduate students. Newspaper reports claimed. In late February 2011, the university formally announced that Ben-Ari would be suspended for two years without salary or right to use research funding, requested the Jerusalem District Prosecutor's Office look into the possibility of reopening the criminal case against him. Eisenstadt, S. N.. It examines written and verbal communications between staff members in the high-turnover environment to determine their role in achieving the goals of the school. Lomsky-Feder, Edna. Unwrapping Japan: society and culture in anthropological perspective, Manchester University Press, ISBN 978-0-7190-3060-4 Ben-Ari, Eyal.

Automatic acquisition of lexicon

Automatic acquisition of lexicon is a computerized process used for the development of a complex morphological lexicon of a language. The lexicon is essential for the NLP, as well as a prerequisite to any wide-coverage parser; the two main requirements represent the morphological description of the language. The aim is to provide lemmas that will serve to the explanation of all the words that occur within the corpus. For the achievement of a quality lexicon it is necessary to manually validate the generated lemmas and iterate the whole process several times; the process is focused on the open word classes. Closed classes are excluded; this method is applicable to the languages with a rich morphology, such as Slovak, Russian or Croatian. Applied to Slovak, being an inflectional language, the automatic acquisition focuses on the inflectional morphology as well as on the derivational morphology; this fact enables the users to find out the information about derivational relations in the lexicon. For example, Slovak word korpusový is an adjectivization of korpus.

Conformably to Benoît Sagot, there are three stages involved in the acquisition of lemmas: 1. Generation and inflection 2. Ranking 3. Manual validation The more iteration will be performed, the more accurate lexicon will be obtained. For each iteration are essential the information given by a manual validator. Firstly, all words which represent the closed word classes are manually excluded from the given corpus. Number of their occurrences in the corpus is provided; the automatic generation comes, when the hypothetical lemmas according to the morphological description of a language are created. Generated lemmas are being inflected, so that all of their inflected forms are built. Obtained forms are associated with a morphological tag. There was created a probabilistic model, represented by a fix-point algorithm, to rank the hypothetical lemmas generated in the first step. Best ranked lemmas are expected to be ideally all correct, whereas the least ranked tend to be incorrect. Correctness of the best- ranked lemmas created in the previous step are checked by the manual validator, who should be a native speaker.

Lemmas are at this stage divided into three categories: - valid lemmas, appended to lexicon - erroneous lemmas generated by valid forms - erroneous lemmas generated by invalid forms Automatic acquisition, in comparison to a purely manual development of the lexicons, seems to be promising, considering the future development, because of the short validation time needed and the small amount of human labor involved. Benoît Sagot publishings