• 반도체디스플레이기술학회지
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• 제10권1호
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• pp.75-81
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• 2011

Today, FPD manufactures are eager to develop larger and larger glass to become the prime market leader. To follow this need, larger AMHS(Automated Material Handling System) development is essential. The radical increase of glass/cassette weight puts a lot of pressure on stocker robot's dual arms, which can cause a damage of expensive glasses and contaminate a clean room facility. In this paper the axiomatic design method is used to institute a design guideline to evenly distribute a pressure throughout the stocker robot structure.

• Journal of Mechanical Science and Technology
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• 제18권5호
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• pp.789-797
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• 2004

The nanoscale sensing and manipulation have become a challenging issue in micro/nano-robotic applications. In particular, a feedback sensor-based manipulation is necessary for realizing an efficient and reliable handling of particles under uncertain environment in a micro/nano scale. This paper presents a piezoresistive MEMS cantilever for nanoscale force measurement in micro robotics. A piezoresistive MEMS cantilever enables sensing of gripping and contact forces in nanonewton resolution by measuring changes in the stress-induced electrical resistances. The calibration of a piezoresistive MEMS cantilever is experimentally carried out. In addition, as part of the work on nanomanipulation with a piezoresistive MEMS cantilever, the analysis on the interaction forces between a tip and a material, and the associated manipulation strategies are investigated. Experiments and simulations show that a piezoresistive MEMS cantilever integrated into a micro robotic system can be effectively used in nanoscale force measurements and a sensor-based manipulation.

• 한국식품위생안전성학회지
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• 제20권3호
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• pp.147-158
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• 2005

본 식품안전 설문지 조사 연구는 가정에서 주부들이 육류, 가금류, 어패류, 날달걀, 육류 가공 식품, 신선한 과일과 야채와 같은 잠재적 위험성 식품을 취급하는 류관 및 섭취방법을 알아보기 위해 행해졌다. $40\%$ 이상의 응답자가 잠재적 위험성 식품을 다룬 후 손은 비누를 사용하지 않고 씻거나 행주로 닦는다고 대답하였다. 과반수 이상의 응답자가 날달걀이 가지고 있는 잠재적 위험성을 인식함이 없이 완전히 조리가 되지 않은 달걀 요리를 먹었다고 하였다. 특히, 날달걀을 깨뜨린 후 $34.0\%$가 손을 세척 하지 않아 날달걀을 다루는 동안 교차 오염의. 위험성이 높음을 나타내었다 채소, 과일의 세척은 $60\%$ 이상의 조사 대상자가 흐르는 물에 그냥 닦는다고 응답하였다 지난 1년 간 잠재적 위험성을 지닌 음식의 섭취를 살펴보면, ‘생선 초밥이나 회'와 ’생굴‘의 섭취가 $78.9\%$와 $45.2\%$로 각각 높게 나타났다. 본 연구 결과에 따르면 많은 주부들이 잠재적 위험성 식품을 취급하고 섭취할 때 특히 '교차 오염', 냉각 습관', ’냉장 보관기간', ‘섭취 방법' 등에서 안전하지 못한 행동들 함으로써 많은 위험성이 내재되어있음을 보였다. 따라서 자녀를 둔 주부들의 학교 급식 참여도를 고려할 때, 주부들이 안전하게 잠재적 위험성 식품을 다루도록 하기 위해 주부들을 위한 식품안전 교육프로그램이 필요하다.

• 해양환경안전학회지
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• 제19권2호
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• pp.138-144
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• 2013

해상에서는 선박 운항과 관련하여 크고 작은 해양사고가 지속적으로 발생하고 있으며, 이러한 해양사고는 소중한 인명의 사상과 재산상의 손실뿐만 아니라 심각한 해양환경 오염 피해를 유발하고 있다. 그리고 해상물동량 증가 및 교통 환경의 복잡화에 따른 해양사고 발생 개연성 및 사고로 인하여 해양오염 피해가 증가하고 있는 것 또한 사실이다. 최근 우리나라에서는 이러한 해상에서의 해상교통 안전성 평가를 위하여 대상해역에서의 해상교통환경과 관련된 일반적인 정보 및 위험도 정보를 제공하고, 해상교통환경 평가를 통한 해역 위험도 여부를 평가할 수 있는 평가지표 개발이 진행 중이다. 본 연구에서는 선박운항자의 위험의식을 바탕으로 하여 다양한 운항 조건에서 선박운항을 재현할 수 있는 선박조종 시뮬레이션을 이용하여 해상교통 평가의 유효성을 확인하고자 하였다. 이러한 시뮬레이션 결과에 대한 주관적 위험도의 측정이 통항선박의 해상교통 평가의 유효성을 대표하는지를 확인하기 위하여 분산분석법을 이용하여 선박운항자의 특성과 선박간 거리, 속력, 조우형태와 같은 각 요소들 간에 차이가 존재하는지를 분석하였다. 또한 각 요소들 간의 위험도 차이 정도를 다중비교를 통하여 분석하여 위험도 차이를 통계적 측면에서 수치의 변화를 확인할 수 있었다.

• Safety and Health at Work
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• 제12권2호
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• pp.261-267
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• 2021

Background: The series of serious industrial accidents in recent years at contractors to large companies has highlighted risk outsourcing as a real and urgent problem. This study aims to review the difference in the degree of risk exposure and the occurrence of industrial accidents depending on the type of company relations. Among in-house contractors, the focus will be on those handling hazardous chemicals that include companies for which outsourcing requires approval. Methods: This study uses the 9th wave of the Industrial Safety and Health Survey (2018). For determining the degree of risk exposure, the occurrence of industrial accidents, and industrial accident rate, multivariate, logistic, and fractional logit, regression analyses were used, respectively. Results: First, In-house contractors' degree of risk exposure is higher than that of the client companies. In particular, this gap is even greater for companies dealing with chemicals. Second, among only those that handle hazardous chemicals, in-house contractors do show a significantly higher rate of industrial accident occurrence. Third, In-house contractors have a significantly higher rate of industrial accidents from diseases than client companies. Conclusion: The analysis supports the intent of the legal amendment that strengthens the protection of in-house contracted workers who handle hazardous chemicals. Second, the results of this study suggest that safety and health management must go beyond legal compliance and ensure that it has substance and effectiveness. Last, there should be policy consideration is necessary to reduce attempts to hide industrial accidents.

• 대한인간공학회지
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• 제32권4호
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• pp.333-340
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• 2013

Objective: The aim of this study is to provide a current knowledge of the multiple issues regarding motion effects on crew performance. Background: The motions of the ship may create motion sickness, nausea and vomit. Also, these motions also disturb the balance of crew members, increase the energy expenditure of crew for shipboard work, and result in increased levels of injury and fatigue. However, the motion effects of the ship on crew performance has not been thoroughly investigated. Method: Participants(N=10) were engaged in an experiment in 2 experimental environments(training ship and ship handling simulator) and 2 navigational conditions(day and night). The COP(Center of Pressure) data were recorded as an objective measure of postural balance control and the SSQ(Simulator Sickness Questionnaire) was used as a subjective measure of sickness. Results: The results showed that COP has a no significant difference based on experimental environments, but significant effect on SSQ. Conclusion: During the virtual simulator navigation, subjects showed significant SSQ level changes, which included decreased SSQ data. But, there is no significant difference of COP between training ship and ship handling simulator. Application: The results of this study could be applied to the next generation of ship design to decrease effect of motion at sea and to increase performance of ship crew.

• 한국환경보건학회지
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• 제50권3호
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• pp.221-228
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• 2024

Background: Social interest is increasing due to frequent accidents caused by chemicals in the electronics industry. Objectives: The purpose of this study is to present a management plan by evaluating the exposure characteristics of dichloromethane (DCM), trichloromethane (TCM), and tetramethyl ammonium hydroxide (TMAH), which are high-risk substances to which people may be exposed in the electronics industry in South Korea. Methods: To investigate the handling companies and status of the hazardous chemicals DCM, TCM, and TMAH, the handling status of the three substances was classified based on electronics industry-related codes from the 2019 Work Environment Survey (Chemical Handling and Manufacturing) data with work environment measurement results for five years. Results: DCM, TCM, and TMAH are commonly used as cleaning agents in the electronics industry. For DCM, it was found that all work environment measurement results from 2018 to 2021 but not 2022 exceeded the exposure standard. Conclusions: Identifying the distribution channels of hazardous chemicals is an intervention point that can reduce exposure to hazardous chemicals. It requires management through tracking systems such as unique verification numbers at the import and manufacturing stages, and proper cultivation of and related support for handling chemicals by business managers.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2011년도 전력전자학술대회
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• pp.271-272
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• 2011

The rising popularity of renewable energy sources resulted in development of the units of higher rated powers. As a result of the limited power handling capacity of individual devices, paralleling is the choice to increase the equipment rating, while keeping the THD of the current at the PCC within the agency specified standards. And their typical power circuit configuration limits the stress on individual devices to an appreciable extent. The main scope of this paper is the analysis of filter structure in paralleling inverter system's operation. Simulation results are shown to verify the theoretical analysis.

• 건축역사연구
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• 제25권3호
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• pp.23-35
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• 2016

The purpose of this study is to classify types of the eaves structure of buildings with the Jusimpo-type structure and to analyze the characteristics of each eaves structure. For this objective, forty buildings were selected and investigated. The results of analysis are summarized as follows. First, the main members of framework which handle a load burden on the long-rafter(長椽) are classified as the Jusim-dori(柱心道里) and the Oemok-dori(外目道里). Based on the method of handling a load, the eaves structure is classified into three types; the Jusim-processing-type(柱心中心形), the Oemok-processing-type(外目中 心形), and the Oemok-processing-variant-type(外目中心變異形). The Jusim-processing-type is the set where the internal length of a long-rafter is longer than the length of the eaves on the basis of the center of a column. The Oemok-processing-type is the set where the external length of a long-rafter is longer than the internal length of it. And the Oemok-processing-variant-type is the set where the internal length of a long-rafter is longer than the external length of it, but it is shorter than the length of the eaves which includes the extruded length of a Buyeon(浮椽). Second, the Jusim-processing-type had been generally adopted in the Jusimpo-type structure of the Goryeo Dynasty. But since the 17th century, the Oemok-processing-type had the highest application rate. Third, the change from the Jusimdori-processing-structure to the Oemokdori-processing-structure means that the long-rafter is moved to the direction of outside of the building, and thus the Jung-dori(中道里) is gradually moved to the column center. And, the change of the eaves with the Jusimpo-type structure was not a process for increasing the length of the eaves but a process for adopting the advantages of the Dapo-type structure by changing the arrangement of purlin. Fourth, the change from the Jusimpo-type structure to the Dapo-type structure could be understood as a process for moving the main point for handling a load from the Jusim-dori to the Oemok-dori.

• 한국항해학회지
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• 제10권2호
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• pp.83-96
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• 1986

In the restricted sea way such as fair way in harbor, narrow channel etc, the safe ship-handling is a very important problem, which is greatly related with turning ability of ships. It is of great importance that ship-handlers can grasp the position of pivoting point varying with time increase at any moment for relevant steering activities. Mean while, in advanced ship-building countries they study and investigated pivoting point related with turning characteristics, hut their main interest lies in ship design, not in safe ship controlling and maneuvering. In this regards it is the purpose of this paper to provide ship-handlers better under standing of pivoting point location together with turning characteristics and then to help them in safe ship-handling by presenting fact that pivoting points vary according to configuration of ships. The author calculated the variation of pivoting point as per time increase for various type of vessels, based on the hydrodynamic derivatives obtained at test of Davidson Laboratory of Stevens Institutes of Technology , New Jersey, U.S.A. The results were classified and investigated according to the magnitude of block coefficient , length-beam ratio, length-draft ratio, rudder area ratio ete, and undermentioned results were obtained. (1) The trajectory of pivoting point due to variation of rudder angle are all the same at any time, though the magenitude of turning circle are changed variously. (2) The moving of pivoting point is affected by the magnitude of block coefficient, length-beam ratio, length-draft ratio, however the effect by rudder area ratio might be disregarded. (3) In controlling and maneuvering of vessels in harbor, ship-handlers might regard that the pivoting point would be placed on 0.2~0.3L forward from center of gravity at initial stage. (4) The pivoting point of VLCC or container feeder vessels which have block coefficient more than 0.8 and length-beam ratio less than 6.5 are located on or over bow in the steady turning. (5) When a vessel intends to avoid some floating obstruction such as buoy forward around her eourse, the ship-handler might consider that the pivoting point would be close by bow in ballast condition and cloase by center of gravity in full-loaded condition.