• Title/Summary/Keyword: Line Standard

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A Study on Airborne Dust and Asbestos Concentrations in Subway Stations in Seoul Area (서울시 지하철 구내의 공기중 분진 농도에 관한 연구)

  • 백남원;박두용;장익선;신용철;이정인
    • Journal of Environmental Health Sciences
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    • v.14 no.2
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    • pp.1-12
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    • 1988
  • Airborne dust and asbestos fiber concentrations were determined in subway stations located in Seoul area. Two stations, such as Eulchiro 4-Ka Station of Line #2, constructed during a period of 1980-1984 and Hyehwa Station of Line #4, opened in 1985, were selected. The results of the study are as follows. 1. Daily time-weighted average (TWA) concentrations of airborne dusts from 07:00 to 20:00 hours in Line #2 and Line #4 were 0.43$\pm$0.08 mg/m$^3$ and 0.37$\pm$0.12 mg/m$^3$, respectively. Thus, the dust levels in Line #2 were significantly higher than the levels in Line #4 (p < 0.05). 2. Dust levels in the morning (07:00-11:00 hours), noon (11:00-16:00 hours) and in the evening (16:00-20:00 hours) in Line #2 were 0.47$\pm$0.17 mg/m$^3$, 0.37$\pm$0.08 mg/m$^3$, and 0.46$\pm$0.07 mg/m$^3$ respectively. Thus, dust levels in the morning and evening (i.e., during rush hours) were significantly higher than levels in the noon (p < 0.02). However, there was no such difference in dust levels by time in Line #4. 3. Airborne total dust concentrations were well below the occupational health standard of 10 mg/m$^3$, however, the levels were exceeding the ambient air standard recommended by the Korean Environment Administration. 4. All of airborne asbestos fiber concentrations were equal to or below 0.005 fibers/cc. The levels are within both occupational health standards and U.S. EPA criteria. 5. A consideration should be given to the improvements of cleaning methods (such as use of vacuum cleaning instead of brushing) and the existing ventilation (such as more air change and filtration of supply air) for a reduction of dust levels. 6. It is recommended that routine monitoring of airborne dusts and asbestos fibers be conducted because more dusts and asbestos fibers can be produced in the air due to the deterioration of facilities by age and water damage in future.

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Design of Channel Impedance Measurement Equipment for Indoor Power Line Communications (옥내 전력선 통신 채널 임피던스 측정 장치 설계)

  • Heo, Yun-Seok
    • The Journal of Information Technology
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    • v.8 no.3
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    • pp.25-33
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    • 2005
  • This paper describe a method for measuring line impedance as a function of frequency for an energized powerline in normal operation. A small sinusoidal signal of a powerline communication utility frequency 30khz$\sim$1Mhz band is continuously injected into the line, and a implemented impedance analyzer calculates the indoor powerline channel impedance from the measured magnitude and phase of resulting voltage and current. The impedance measurement is executed over a range of frequencies to produce a wideband impedance versus frequency characteristic. Implemented impedance analyzer can analysis powerline communication environments measuring line impedance due to load caused in indoor. And measured analysis information through the database can use to evaluate performance of modem and to decide test environment standard.

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Studies on Breeding of F$_1$ Hybrid Rice Using the Korean Cytoplasmic and Genetic Male Sterile Rice I. Breeding of Hybrid Rice Using the Cytoplasmic-Genetic Male Sterility (세포질적 유전자적 웅성불임을 이용한 벼 일대잡종 육성연구 I. 세포질적 유전자적 웅성불임계통 이용과 일대잡종 육성)

  • Suh, Hak-Soo;Lee, Chang-Un;Heu, Mun-Hue
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.30 no.4
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    • pp.431-435
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    • 1985
  • Nine hybrid rices crossed between Korean cytoplasmic-genetic male sterile rices having the WA cytoplasm and the Korean restorer lines or varieties, HR1619A/Nampungbyeo, HR1619A/Gayabyeo, HR1619A/Line234, TongilA/Nampungbyeo, TongilA/Cheongcheongbyeo, Suwon 296A/Line 209, Suwon 296A/Line 237, Suwon 296A/Line 252 and Line 201A/Line 234, and their parents were grown at Yeungnam University in 1984. The rough rice yield of the hybrids Line 201A/Line 234, TongilA/Nampungbyeo and HR1619A/Nampungbyeo were 939, 927 and 900 Kg/10a respectively. The heterosis(F$_1$/Midparent) of the above three hybrids was 40%, 20% and 19%, the heterobeltiosis(F$_1$/Better parent) was 36%, 17% and 10%, and the standard heterosis (F$_1$/Standard variety, Cheongcheongbyeo) was 19%, 17% and 14% respectively. The hybrids HR1619A/ Gayabyeo and Suwon 296A/Line 237 showed negative heterosis in grain yield. Significant heterobeltiosis for grain number per panicle was found while less or no heterobeltiosis was observed in panicle number per hill, 1000-grain weight and grain fertility. The bacterial leaf blight disease reaction of the hybrids tested was almost the same as that of one parent at least. The amylose content of the hybrids was medium to low the same as their parents. The protein content and alkali digestion value of the hybrids were almost the same as their parents.

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Architects' PLAZA - overseas journal (건축마당 - 해외잡지동향)

  • Choi, Hyun-Ah
    • Korean Architects
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    • s.487
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    • pp.94-98
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    • 2009
  • 이번 호의 Project 섹션에서는 Bernard Tschumi Architects의 Acropolis Museum, High Standard라는 주제 아래에서 James Corner Field Operation의 High Line, Polsh다 Partnership의 Standard New York을, 그리고 UNStudio의 MUMUTH Music Theater가 소개되고 있다. Building Type Study에서는 '도심의 녹색 건축(Green Civie Building)'이라는 주제로 Anmahian Winton Architects의 Community Rowing Boathouse, Safdie Rabines Architecs의 Baldwin Hills Scenic Overlook, 그리고, Jane F. Kolleny의 Whistler Public Library에 대해 소개하고 있다.

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Union and Division using Technique in Fingerprint Recognition Identification System

  • Park, Byung-Jun;Park, Jong-Min;Lee, Jung-Oh
    • Journal of information and communication convergence engineering
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    • v.5 no.2
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    • pp.140-143
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    • 2007
  • Fingerprint Recognition System is made up of Off-line treatment and On-line treatment; the one is registering all the information of there trieving features which are retrieved in the digitalized fingerprint getting out of the analog fingerprint through the fingerprint acquisition device and the other is the treatment making the decision whether the users are approved to be accessed to the system or not with matching them with the fingerprint features which are retrieved and database from the input fingerprint when the users are approaching the system to use. In matching between On-line and Off-line treatment, the most important thing is which features we are going to use as the standard. Therefore, we have been using "Delta" and "Core" as this standard until now, but there might have been some deficits not to exist in every person when we set them up as the standards. In order to handle the users who do not have those features, we are still using the matching method which enables us to make up of the spanning tree or the triangulation with the relations of the spanned feature. However, there are some overheads of the time on these methods and it is not sure whether they make the correct matching or not. In this paper, introduces a new data structure, called Union and Division, representing binary fingerprint image. Minutiae detecting procedure using Union and Division takes, on the average, 32% of the consuming time taken by a minutiae detecting procedure without using Union and Division.

Automation of Skin Allergy Test using Fuzzy Set (Fuzzy Set을 이용한 피부반응 검사의 자동화 연구)

  • Shim, Chul;Jeong, Byeong-Sun;Lee, Myeong-Ku;Park, Mi-Gnon
    • Proceedings of the KOSOMBE Conference
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    • v.1990 no.05
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    • pp.43-46
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    • 1990
  • Modern society is prevailed a lot of allergies. So, the allergy test is very important. There are many kinds of allergy test. A doctor usually uses skin allergy test among many allergy tests. However, little standadization and objectivity of grading-standard has been established in the skin allergy test. A measurement of the reaction area has been a major objective to perform skin allergy test. Recently, a doctor's method is to measure the reaction area after drawing a line that represents the reaction area on the skin. But this method differs slightly from the real reaction area and individual doctor's measurement is different, because the edge of the reaction area is obscure. In this paper, we propose a algorithm which is able to detect vague edges using the fuzzy set. The algorithm that detects the line and curve is proposed first. Here, the maximum value is calculated by comparing the membership function of the line and curve seperately. We also encode the direction of the line and curve by using 8-direction code. Then, we calculate the reaction area by measuring the pixels which are inside the reaction area. And finally the Allergy grade is decided by grading-standard, and we accomplish faster, the 80re accurate and objective allergy grade decision.

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A study on the electromigration phenomena in Al-1%Si thin film interconnections with Ti underlayers (Ti underlayer를 갖는 AI-1%Si 박막배선에서의 일렉트로마이그레이션 현상에 관한 연구)

  • 유희영;김진영
    • Journal of the Korean Vacuum Society
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    • v.8 no.1
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    • pp.31-35
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    • 1999
  • In this paper, the lifetime dependence as a function of the line length of Al-1%Si thin film interconnections due to electromigration in semiconductor devices was studied. Al-1%Si thin film interconnections with a pattern of straight type were formed by using a standard photolithography process. The test patterns manufactured have line lengths in the range of 100 to 1600 $mu extrm{m}$. Al-1%Si thin film interconnections with Ti underlayers showed longer lifetime than those without Ti underlayers. Ti underlayers are believed to improve electromigration resistance resulting in a longer lifetime in Al-1%Si thin film interconnections. The dependence of lifetime on the line length in Al-1%Si/Ti thin film interconnections shows a saturation tendency near 800 $\mu\textrm{m}$ line length.

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A Study on Evaluation of J$_{IC}$ for SB41 Steel with Measured Bluntion Line (실측 둔화직선을 이용한 SB41 강의 J$_{IC}$평가에 관한 연구)

  • 허정원;오세욱;유재환;김득진;차재준
    • Journal of Ocean Engineering and Technology
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    • v.8 no.2
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    • pp.38-46
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    • 1994
  • The method of JSME S001-83 and ASTM E813-87 have been adapted for evaluation of the elastic-plastic fracture toughness J sub(IC) of SB41 steel. This SB41 steel have the characteristics of low-stength CT specimens. The test results obtained have been considered and compared on the basis of resulted data from two kinds of methods(JSME S001-83, ASTM E813-87) and two kinds of specimen configurations(smooth, side-grooved). On the basis of results from consideration and comparison, the difficulties for its application were presented in case when the standard ASTM E813-87 method was employed for the measurement of J sub(IC) in SB41 steel. A modified method was applied for measuring J sub(IC) in SB41 steel that it used the blunting line real-measured by experiment instead of the standard blunting line theoretically determined, and the result from that procedure was analyzed and the usefulness of that method was examined and considered.

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Development of the Technical Calculation System for Transmission Line (송전선로 설계 기술자료 계산시스템 개발)

  • Byun Gang;Min Byeong Wook;Wi Hwa Bog;Kim Sae Hyun;Park Kee Yong;Namkung Do
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.488-490
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    • 2004
  • The technical data for transmission line design and maintenance are calculated by a very complicated numerical formula so it is almost impossible to solve them by hand. Therefore the TOWER+ EXPERT SYSTEM was developed to systematically support technical data for transmission line design and maintenance. This system is able to calculate technical data which is applied to all conductors in our county, - that is 12 kinds of systems with 86 numbers of standard conductors, - and is programed to be user friendly by adopting dialogue windows, menu selection functions. Moreover, it minimizes input data by automatically providing standard transmission line design data, and it includes guidance of applicable work, program usage, data input process, help, explanation of terms and automatic error recovery functions that even a beginner can easily use.

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A Study of the Charging Current Effect on Underground Distribution Line in Electric Railway (전철 지중배전선로의 충전전류보상에 관한 연구)

  • Kim, Yang-Su;Jang, Woo-Jin
    • Proceedings of the KSR Conference
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    • 2008.11b
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    • pp.214-218
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    • 2008
  • Because on the high-tension underground distribution line of an electric railway high voltage XLPE Cable two or three circuits between railway stations with a standard as receiving transformer facilities are established at a $30km{\sim}50km$ interval, reactive power in which the phase of a current is larger than that of a voltage is supplied when trains are not working, so when there are no loading or low loading as night. Due to the long-distance trend of the underground distribution system on an alternating current railway distribution line, the terminal voltage of a transformer is over the standard voltage, and after all, commercial cycle overvoltage is continued. To solve this problem, the shunt reactor is installed in middle of power distribution lines to maintain receiver voltage meted under the allowance regulation through control of the reactive power. Also, in case that the thickness of single cable is over $60mm^2$ and length of line is about over 30km, a circuit breaker is broken by shorting shunt ability of charging current in excess of shunt current(31.5A.rms). Therefore, this thesis presents installing the location of shunt reactor for quantitative analysis by using optimum algorism for compensation and control of the charging current.

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