• Title/Summary/Keyword: near and far-field

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Discovery of a Faint Quasar at z ~ 6 and Implications for Cosmic Reionization

  • Kim, Yongjung;Im, Myungshin;Jeon, Yiseul;Kim, Minjin;Choi, Changsu;Hong, Jueun;Hyun, Minhee;Jun, Hyunsung David;Karouzos, Marios;Kim, Dohyeong;Kim, Duho;Kim, Jae-Woo;Kim, Ji Hoon;Lee, Seong-Kook;Pak, Soojong;Park, Won-Kee;Taak, Yoon Chan;Yoon, Yongmin
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.37.3-38
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    • 2016
  • Recent studies suggest that faint active galactic nuclei may be responsible for the reionization of the universe. Confirmation of this scenario requires spectroscopic identification of faint quasars ($M_{1450}$ > -24 mag) at z > 6, but only a very small number of such quasars have been spectroscopically identified so far. Here, we report the discovery of a faint quasar IMS J220417.92+011144.8 at z ~ 6 in a $12.5deg^2$ region of the SA22 field of the Infrared Medium-deep Survey (IMS). The spectrum of the quasar shows a sharp break at ${\sim}8443{\AA}$, with emission lines redshifted to $z=5.944{\pm}0.002$ and rest-frame ultraviolet continuum magnitude $M_{1450}=-23.59{\pm}0.10$ AB mag. The discovery of IMS J220417.92+011144.8 is consistent with the expected number of quasars at z ~6 estimated from quasar luminosity functions based on previous observations of spectroscopically identified low-luminosity quasars. This suggest that the number of $M_{1450}$ ~ -23 mag quasars at z ~ 6 may not be high enough to fully account for the reionization of the universe. In addition, our study demonstrates that faint quasars in the early universe can be identified effectively with a moderately wide and deep near-infrared survey such as the IMS.

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A Study on Effective Adjustment of the Curriculum in Film and Film Related Major in Korean Colleges (국내 대학의 영화 및 영화 관련학과 교과과정 효율화를 위한 연구)

  • Lee, Chan-Bok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.11
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    • pp.3514-3523
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    • 2009
  • Before 1990's, Korea had only few colleges that had film and film related majors. As Korean film industry started its marvelous improvement in both commercial and artistic phase, many colleges were interested in this new academic field. They hurried up to launch this new and profitable major; as a result, Korea now has more than hundred colleges and universities that has film related majors. Each college enumerates numbers of academic courses that may look reasonable; they have almost every course a fine film school should provide such as film theory, production, and performance in film. Lots of film schools offer lots of film courses; and they look alike. One unique thing in film major is its vast sub fields and categories. After you decide to study film, you have to select what specific field in film you want to study. Studying film theory and film production can be as different as majoring physics and physical education. The problem Korean colleges are dealing with is that there are too much film schools, and moreover those colleges have similar curriculums that just look like a department store that sells everything. One suggestion is specializing its curriculum in which the school can take advantages using their special conditions. San Francisco Art Institute is one of United States well known private film schools, but many people remember this school as a specialized film school in experimental film. San Francisco where this school is located has had many liberal and experimental artists as the city has been supporting and offering them an environment they can concentrate their work. Naturally, the school has world famous faculty members in experimental film, and students who want to study and make experimental film come to this school from all over the world because they know this school would be the best to study experimental film. There are many film schools in metro Los Angeles area; since its location near Hollywood, no wonder these schools concentrate on film producing and film production. They take advantage of their geographical location to hire film industry professional and to focus on commercial feature film productions. What we can do now to adjust the curriculum in film and film related major in Korean colleges is to adapt new standards in this changed film industry. One school can emphasize digital production while another school focuses on digital intermediate process. But if one school tries to both fields or all fields of film major just like we have done so far, the school could not take care of all the equipment and the faculty that the fields would need. Korean film schools should devide the field in film major and concentrate what they selected. Selection and concentration can be and should be applied in Korean film schools.

Investigation of Poultry Farm for Productivity and Health in Korea (한국에 있어서 양계장의 실태와 닭의 생산성에 관한 조사(위생과 질병중심으로))

  • 박근식;김순재;오세정
    • Korean Journal of Poultry Science
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    • v.7 no.2
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    • pp.54-76
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    • 1980
  • A survey was conducted to determine the status of health and productivity of poultry farms in Korea. Area included Was Kyunggido where exist nearly 50% of national poultry population. From this area, 41 layer and 34 broiler farms covering 21 Countries were selected randomly for the survey. When farms were divided in the operation size, 95.1% of layer and 82.3% of broiler farms were classified as business or industrial level while the rest were managed in a small scale as part time job. Generally layer farms had been established much earlier than broiler farms. Geographically 10.7% of layer farms were sited near the housing area such as field foreast and rice field. No farms were located near the seashore. The distance from one farm from the other was very close, being 80% of the farms within the distance of 1km and as many as 28% of the farms within loom. This concentrated poultry farming in a certain area created serious problems for the sanitation and preventive measures, especially in case of outbreak of infectious diseases. Average farm size was 5,016${\times}$3.3㎡ for layers and 1,037${\times}$3.3㎡ for broilers. 89.5% of layer ana 70.6% of broiler farms owned the land for farming while the rest were on lease. In 60% of layer farms welters were employed for farming while in the rest their own labour was used. Majority of farms were equipped poorly for taking necessary practice of hygiene and sanitation. The amount of disinfectant used by farms was considerably low. As many as 97.6% of lave. farms were practised with Newcastle(ND) and fowl pox(F$.$pox) vaccine, whereas only 43.6% and 5.1% of broiler farms were practised with ND and F$.$pox vaccine, respectively. In 17-32.7% of farms ND vaccine was used less than twice until 60 days of age and in only 14.6% of farms adult birds were vaccinated every 4months. Monthly expense for preventive measures was over 200,000W in 32% of farms. Only 4.9-2.7% of vaccine users were soaking advice from veterinarians before practising vaccination, 85% of the users trusted the efficacy of the vaccines. Selection of medicine was generally determined by the farm owner rather than by veterinarans on whom 33.3% of farms were dependant. When diseases outbroke, 49.3% of farms called for veterinary hospital and the rest were handled by their own veterinarians, salesmen or professionals. Approximately 70% of farms were satisfied with the diagnosis made by the veterinarians. Frequency of disease outbreaks varied according to the age and type of birds. The livabilities of layers during the period of brooding, rearing ana adultwere 90.5, 98.9 and 75.2%, respectively while the livalibility of broilers until marketing was 92.2%. In layers, average culling age, was 533.3 day and hen housed eggs were 232.7. Average feed conversion rates of layers and broilers were 3.30 and 2.48, respectively. Those figures were considerably higher than anticipated but still far lower than those in developed countries.

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Present Status and Future Prospect on Fishing Industry in North Korea (북한수산업(北韓水產業)의 현황(現況)과 전망(展望))

  • Lee, Byoung-Gee;Kim, Jin-Kun;Choe, Jong-Hwa
    • Journal of Fisheries and Marine Sciences Education
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    • v.3 no.2
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    • pp.73-82
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    • 1991
  • In recent years, the communication and the trade between the Republic of Korea(South Korea) and the Communist bloc has been activated. The simultaneous entrance of South Korea and North Korea to the United Nations will accelerate the political dialogue and also the trade which is indirectly carried out through a third country at present will be turned into direct way. Fisheries products are also treated as one of the important trade goods and there is a hopeful prospect that the amount of trade will be steeply increased in the near future. Furthermore, there is a great possibility of development up to the joint utilization of fishing grounds or the joint investment in fisheries projects. Concerning such points, since it is very much important to understand the present status of fisheries in North Korea, the author made a study on this field as requested by the Board of Unification, and report a part of the study here. The prominent character of North Korea's ruling sea area is that the sea is completely separated into two regions-the East Sea Region and the West Sea Region-and no continuity exists between them. The East Sea Region locates in the fringe of the biggest fishing ground of the world-the North Pacific Ocean-and very rich in resources not only warm water fishes but also cold water fishes. Especially alaska pollack, Theragra chalcogramma, is caught abundantly in this region. Contrary to that, fishing activity in the West Sea Region seems to be interrupted in winter. Even though some valuable warm water fishes-yellow corvenia, Pseudosciaena manchurica, and hair tail, Trichiurus lepturus, and so forth-come to this region from spring to summer along the coast line of this region for spawning, and vigorous fishing activity is carried out. But the most of them migrate southward to the neighboring waters of Cheju Island for wintering from autumn to winter, and so the fishing activity in this region seems to be interrupted greatly during winter. The total number of fishing boats in North Korea is estimated at 36 thousand and the rate of mechnization at about 70% compared with 99 thousand and 78% in South Korea. North Korea proclaimed an exclusive economic zone of 200 nautical miles in 1977. Specific character of this zone is setting of military boundary zone, up to 50 miles from the base line in the East Sea Region and also it covers whole region of the economic zone in the West Sea Region. Especially in the East Sea Region she set up a straight base line which can not be permissible by the international law. North Korea's statistics on fisheries product has not been announced officially on account of her unique isolationism, but it can be estimated through several data procured. At the first, the amount of fisheries products in the North Korea is reported as about 1.7 million ${\frac{M}{T}}$ by Fisheries Statistics which issued by the FAO in 1987, but a North Korea's trade organization announced the amount as 3.5 million ${\frac{M}{T}}$ in 1988. The former seems to be underestimated and the latter must be an exaggeration. According to Chikuni, who is a Japanese worker for FAO, prepared the unofficial statistics based on the evidence which he collected through the fineries development plan of the FAO/UNDP, and estimated the mean amount between 1982 and 1984 was 2.4 million ${\frac{M}{T}}$ or so. The Board of Unification estimated on the basis of various factors that the amount was 2.2 million ${\frac{M}{T}}$ or so in 1987 and in 1988. This seems to be the most reasonable. To solve the chronic lack of foreign currency, North Korea makes effort on the development of fisheries, and has even aimed fisheries product at 11 million ${\frac{M}{T}}$ by 1993, but this target looks unrealistic under the present circumstances. Somehow, we can exploit her extreme policy which has gone so far as to establish such an excessive and impractical target. Nevertheless this will be helpful to promote the joint development of the fishery activity between South Korea and North Korea.

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Control of Human Clonorchiasis at Gokseong-gun and Sunchang-gun near the Sumjin River in Korea (섬진강 유역 곡성군, 순창군 지역 주민의 간흡충증 관리)

  • Kim, Suk-Il;Yun, Woo-Sang
    • Journal of agricultural medicine and community health
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    • v.29 no.1
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    • pp.163-175
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    • 2004
  • Objectives: This study was carried out to decrease the prevalence of human clonorchiasis and to evaluate the control effect in two Clonorchis sinensis-endemic area of Gokseong-gun and Sunchang-gun adjacent to the Sumjin River in Korea. Methods: The formalin-ether concentration method for stool egg examination or ELISA was applied for the diagnosis of clonorchiasis. As a primary survey, according to the non-probability sampling, a total of 1,2.13 inhabitants at Gokseong-gun were screened through the stool examination, and 1,004 inhabitants at Sunchang-gun were screened through the ELISA. The humans infected with C. sinensis were medicated with praziquantel and educated for the prevention of reinfection with the fluke. After 9 months, as a secondary survey, each prevalence of 616 inhabitants at Gokseong-gun and 2.637 inhabitants at Sunchang-gun was followed-up for the decrease of human clonorchiasis. Results: The prevalence before the mass control was 39.0% at Gokseong-gun and 30.1% at Sunchang-gun in average from 61.5% to 8.9% according to the villages (Myeon) of the survey. In the riverside villages to the Sumjin River the prevalences were higher than other villages located far from the river. The prevalence after the control was decreased to the level of 22.4% at Gokseong-gun(P<0.0001) and 16,3% at Sunchang-gun (P<0.0001). Conclusions: These results suggested that human clonorchiasis was still highly endemic in riverside area of the Sumjin River and could be decreased through the control activities such as diagnosis, medication and education. It was highly recommended that a integrated control such as those of the present study must be adopted in other localities along the Sumjin River for the eradication of human clonorchiasis.

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A Study on the Meaning and Future of the Moon Treaty (달조약의 의미와 전망에 관한 연구)

  • Kim, Han-Taek
    • The Korean Journal of Air & Space Law and Policy
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    • v.21 no.1
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    • pp.215-236
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    • 2006
  • This article focused on the meaning of the 1979 Moon Treaty and its future. Although the Moon Treaty is one of the major 5 space related treaties, it was accepted by only 11 member states which are non-space powers, thus having the least enfluences on the field of space law. And this article analysed the relationship between the 1979 Moon Treay and 1967 Space Treaty which was the first principle treaty, and searched the meaning of the "Common Heritage of Mankind(hereinafter CHM)" stipulated in the Moon treaty in terms of international law. This article also dealt with the present and future problems arising from the Moon Treaty. As far as the 1967 Space Treaty is concerned the main standpoint is that outer space including the moon and the other celestial bodies is res extra commercium, areas not subject to national appropriation like high seas. It proclaims the principle non-appropriation concerning the celestial bodies in outer space. But the concept of CHM stipulated in the Moon Treaty created an entirely new category of territory in international law. This concept basically conveys the idea that the management, exploitation and distribution of natural resources of the area in question are matters to be decided by the international community and are not to be left to the initiative and discretion of individual states or their nationals. Similar provision is found in the 1982 Law of the Sea Convention that operates the International Sea-bed Authority created by the concept of CHM. According to the Moon Treaty international regime will be established as the exploitation of the natural resources of the celestial bodies other than the Earth is about to become feasible. Before the establishment of an international regime we could imagine moratorium upon the expoitation of the natural resources on the celestial bodies. But the drafting history of the Moon Treaty indicates that no moratorium on the exploitation of natural resources was intended prior to the setting up of the international regime. So each State Party could exploit the natural resources bearing in mind that those resouces are CHM. In this respect it would be better for Korea, now not a party to the Moon Treaty, to be a member state in the near future. According to the Moon Treaty the efforts of those countries which have contributed either directly or indirectly the exploitation of the moon shall be given special consideration. The Moon Treaty, which although is criticised by some space law experts represents a solid basis upon which further space exploration can continue, shows the expression of the common collective wisdom of all member States of the United Nations and responds the needs and possibilities of those that have already their technologies into outer space.

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