• 한국세라믹학회지
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• 제23권5호
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• pp.47-54
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• 1986

The structures of crystalline vitreous and liquid $SiO_2$ were Monte carlo simulated employing the potential energy function comprising Lennard-Jones 2-body and Axilrod-Teller 3-body potentials. Although the Si-O-Si angular distribution functions obtained in the simulation appear to be higher than the experimental results the other simulation results including SiO, O-O and Si-Si radial distribution functions and O-Si-O anglular distribution functions agree well with experimental data within acceptable limits. Themost important outcome in this study is that various $SiO_2$forms were successfully reproduced with the same potential energy function.

• International Journal of Korean Welding Society
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• 제1권1호
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• pp.13-16
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• 2001

High speed seam weldability of tin coated steels was investigated. Welding was performed by the laboratory wire seam welder that was equipped with process monitoring system Test results showed that increase in applied current and pressure reduced the total resistance across the welding electrodes. Lower and upper limits of welding current increased as the sheet thickness increased, while the acceptable welding condition range decreased. However, extremely low electrode pressure produced unstable welding condition range. The results also demonstrated that slower welding speeds widened the optimum welding heat input range.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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• pp.125-128
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• 2005

The visual perception tests were conducted to determine limits of luminance of a LCD TV from a viewpoint of glare. The results showed that people, who watch TV in their living room, perceive glare above $410\;cd/m^2$ at full window and $590\;cd/m^2$ at 1/25 window.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1993년도 추계학술대회논문집; 반도아카데미, 26 Nov. 1993
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• pp.157-161
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• 1993

Optical devices and electronic equipments used in the laboratory of the synchrotron light source building of the accelerator have stringent vibration limits. In order to control the vibration of the building structure and HVAC systems which are main vibration sources are evaluated using experimental modal analysis. Double anti-vibration system is used for the HVAC system and results show that the double anti-vibration system reduces the vibrations of the building to acceptable levels.

• 한국산업보건학회지
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• 제25권2호
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• pp.134-145
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• 2015

Objectives: An objective of this study was to perform a risk assessment and social cost-benefit analysis for revising permissible exposure limits for seven substances: Nickel(Insoluble inorganic compounds), benzene, carbon disulfide, formaldehyde, cadmium(as compounds), trichloroethylene, touluene-2,4-diisocyanate. Materials and Methods: The research methods were divided into risk and hazard assessment and cost-benefit analysis. The risk and hazard assessment for the seven substances consists of four steps: An overview of GHS MSDS(1st), review of document of ACGIH's TLVs (2nd), comparison between international occupational exposure limits and domestic permissible exposure limits(3rd), and analysis of excess workplace and excess rate for occupational exposure limits based on previous work environment measurement data(4th). Total cost was estimated using cost of local exhaust ventilation, number of excess workplace and penalties for exceeding a permissible exposure limit. On the other hand, total benefit was calculated using the reduction rate of occupational disease, number of workplaces treating each substance and industrial accident compensation. Finally, the net benefit was calculated by subtracting total cost from total benefit. Results: All the substances investigated in this study were classified by CMR(Carcinogens, Mutagens or Reproductive toxicants) and their international occupational exposure limits were stricter than the domestic permissible exposure limits. As a result of excess rate analysis, trichloroethylene was the highest at 11%, whereas nickel was the lowest at 0.5%. The excess rates of all substances except for trichloroethylene were observed at less than 10%. Among the seven substances, the total cost was highest for trichloroethylene and lowest for carbon disulfide. The benefits for the seven substances were higher than costs estimated based on strengthening current permissible exposure limits. Thus, revising the permissible exposure limits of the seven substances was determined to be acceptable from a social perspective. Conclusions: The final revised permissible exposure limits suggested for the seven substances are as follows: $0.2mg/m^3$ for nickel, 0.5 ppm(TWA) and 2.5 ppm(STEL) for benzene, 1 ppm(TWA) for carbon disulfide, $0.01mg/m^3$(TWA) for cadmium, 10 ppm(TWA) and 25 ppm(STEL) for trichloroethylene, 0.3 ppm(TWA) for formaldehyde, and 0.005 ppm(TWA) and 0.02 ppm(STEL) for toluene diisocynate(isomers).

• 한국산업보건학회지
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• 제4권1호
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• pp.33-42
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• 1994

This study was carried out to assess worker exposure to vinyl chloride monomer (VCM) and to present control measures in the factories processing and producing polyvinyl chloride (PVC) resin. The conclusion remarks are as follows. Only two personal samples in the factory ("E") processing polyvinyl chloride resin were analysed to be 27.6 ppm and 12.6 ppm, respectively. But, these concentration exceed 1 ppm, Permissible Exposure Limits (PEL) of OSHA. So, worker's exposure to VCM at "E" factory should be reevaluated. In "A", "B" and "C" factory producing polyvinyl chloride resin, the average worker's exposures to VCM were 0.12 ppm, 0.86 ppm and 1.23 ppm, respectivery. Worker exposure to VCM at distillation and dry process was higer than other processes at "A" factory. The average exposure concentration of worker at polymerization process of "B" and "C" factory was 1.23 ppm, and 1.46 ppm respcetively. These concentration exceed 1 ppm, Permissible Exposure Limits of OSHA. Control room of "B" and "C" factory had 0.91 ppm and 0.65 ppm of worker's exposure concentration respectively. "A" factory was evaluated to be "acceptable", but "B" and "C" factories were evaluated to be "not acceptable", by the workplace exposure assessment program of AIHA. Process other than bagging and control room of "A" factory was evaluated to "not acceptable". Immediate correction measures for preventing workers from exposure to VCM should be performed in the factories or process that were evaluated to be "not acceptable". After these control measures are taken, worker exposure to VCM must be reevaluated through personal air monitoring. Control measures presented by this study are complete sealing of connecting pipe lines, flanging, packing, bolting and nutting. Periodic leak test for leak parts is also required. And positive pressure facility should be constructed at control room of "B" and "C" factory. Fresh air through cleaner such as HEPA filter should be supplied to control room. In addition to these control measures, periodic personal monitoring for evaluating worker exposure to VCM should be performed.

• 한국조경학회지
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• 제41권6호
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• pp.171-184
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• 2013

최근 몇 년간 수변공간 개발에 대한 관심이 증가하면서 지속가능한 지역균형 발전을 목표로 하는 지역개발 정책 및 사업이 증가하였다. 이러한 과정에서 생활환경 변화에 대한 지역문제가 발생하게 되었고, 지역주민태도를 반영한 개발계획의 중요성이 부각되었다. 본 연구에서는 새로 조성된 수변공간에 대하여 허용 가능한 개발형태 분석 및 향후 개발목표를 설정하기 위해, 사회교환이론을 바탕으로 지역주민 태도를 고려하여 LAC 시스템의 첫 번째 단계에 대한 분석을 실시하였다. 이를 위해 여주시 지역주민 240명을 대상으로 수변공간 개발에 대한 주민태도, 허용 가능한 수변공간 개발형태, 주민특성을 설문하였다. 설문한 데이터에 대한 기술통계분석, 요인분석을 실시한 뒤, 수변공간 개발에 대한 주민태도에 따른 허용 가능한 개발 형태를 알아보기 위해 다중회귀분석을 실시하였다. 다음으로 거주특성과 수변공간 개발에 대한 주민태도와의 차이를 알아보기 위해 기술통계분석, 요인분석, T-test, 일원분산분석(one-way ANOVA)를 실시하였다. 그 결과, 여주시 지역주민들이 허용하는 수변공간 개발 형태는 자연교육중심 개발 형태라는 것을 확인할 수 있었으며, 거주지역에 따라 수변공간 개발에 대한 형태에 차이가 나타나는 것을 확인할 수 있었다. 본 연구의 결과를 통해 수변공간의 개발 및 관리 목적을 설정하고, LAC 후속단계인 휴양자원 등급화의 적용범위에 대한 기준을 마련할 수 있었다.

• 대한교통학회지
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• 제24권1호
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• pp.7-18
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• 2006

오늘날 도시 지역의 화물차량의 통행은 통행의 제한이나 관리활동의 부재의 이유로 도로혼잡 문제화 환경 및 도로파손의 사회비용 증가의 문제점을 증가시키고 있다. 이러한 문제의 해결을 위해 본 연구에서는 도시 내 화물차량의 효율적인 관리를 위한 화물통행망 구축방안을 제안하고자 한다. 본 논문을 통해 제안된 화물 통행망 구축방안은 죤 들의 화물차량 유출입 통행량의 차이에 따라 나타나는 교차통행량을 수용할 수 있는 간선망을 배정하는 방법을 이용하였고, 간선의 기능을 수행하는 도로의 위계별로 나타나는 용량차이를 고려하기 위하여, 도로를 '도로용량편람'의 용량산정을 위한 분류방식을 적용하여 고속도로, 다차로 도로, 도시 및 교외 간선도로로 구분하였으며, 요구되는 차로수 별 통행 가능한 화물차량의 통행수를 산정하였다. 이때, 차로수 별 화물차량 통행량은 도시 계획자의 목적에 따라 적용 가능하도록 교통류 중 화물차량의 유입 허용비율에 따라 각각 산정하였다 최종적으로 개발된 화물통행망 구축방안을 서울시를 대상으로 적용해봄으로써 실질적인 효용과 적용 가능성을 확인하였다.

• 안보군사학연구
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• 통권7호
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• pp.1-24
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• 2009

This article deals with military thought in general. First I tried to distinguish 'thought' from 'theory', 'philosophy', and 'principle'. Thought means the act of thinking about or considering something, an idea or opinion, or a set of ideas about a particular subject, e.g. military affairs in the present discussion. Theory means a formal statement of the rules on which a subject of study is based or of ideas which are suggested to explain a fact or event or, more generally, an opinion or explanation. Philosophy means the use of reason in understanding such things as the nature of reality and existence, the use and limits of knowledge. Principle means a basic idea or rule that explains or controls how something happens or works. Chapter 3 summarized the characteristics of military thoughts into five points', (i) it is closely related with concrete experiences of a nation; (ii) it includes philosophical and logical arguments; (iii) it relies heavily on the political thought of a nation; (iv) it includes necessarily value-judgments; (v) it contains visions of a nation which are not only descriptions or explanations of military affairs, but also evaluations and advocacies. Chapter 4 considers the relation of international political thoughts to military thought. Throughout the history of the modem states system there have been three competing traditions of thought: the Hobbesian or realist tradition, which views international politics as a state of war; the Kantian or universalist tradition, which sees at work in international politics a potential community of mankind; and the Grotian or internationalist tradition, which views international politics as taking place within an international society. Chapter 5 considers the law of war, which is a body of law concerning acceptable justifications to engage in war (jus ad bellum) and the limits to acceptable wartime conduct (jus in bello). Among other issues, modem laws of war address declarations of war, acceptance of surrender and the treatment of prisoners of war, military necessity along with distinction and proportionality, and the prohibition of certain weapons that may cause unnecessary suffering.

• 수산해양교육연구
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• 제25권5호
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• pp.1055-1067
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• 2013

We attempted to apply the HACCP system adopted in the food industry to a olive flounder (Paralichthys olivaceus) aquaculture farm to ensure the hygiene safety of farmed fish. In this study, HACCP system procedures, including HACCP team organization, critical point determination, establishment of standard limits etc., were established using Codex 12 procedures. To determine whether hazards were critical elements, we evaluated the likelihood and seriousness of each hazard element. The likelihood of residual medicine exceeding the acceptable limit in shipped fish products was demonstrated to be a critical hazard element. Management of the shipment stage was determined to be a critical control point (CCP). Checking the records for stock and release and maintaining a history of medicine use before shipping the fish were suggested as monitoring methods. The standards for acceptable residual medicine were set based on relevant laws and regulations, and then the limits were adapted and established for the CCP. An HACCP plan applicable to olive flounder farms was established.