• 한국ITS학회 논문지
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• 제10권1호
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• pp.16-26
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• 2011

가변속도제어(Variable Speed Limit ; VSL)는 교통상황에 따라 속도를 차등 제한하여 혼잡 또는 사고지점에 도달하기전 차량간, 차로간 속도편차를 감소시킴으로써 사고를 예방하고 총 지체를 최소화하기 위한 연속류 ITS기법 중 하나이다. 본 연구에서는 가변속도 제어시 연속류 기본구간의 동적교통류에 대한 수학적 분석결과를 기초로 가변속도제어 수행모형을 제시하고 효과분석을 수행하였다. 가변속도제어모형은 병목현상 발생시 상류부에 전파되는 충격파의 속도를 최소화 함으로써 지체를 감소시킬 수 있도록 graphical solution을 적용하여 제시한다. 또한 가변속도 제어시 해당 지점으로부터 하류부로 전파되는 충격파의 생성 및 움직임을 모형화 하여 재현하며 그 방법론으로는 Cell-Transmission Model 및 Supply-Demand Method를 적용하였다. 가변속도제어 적용에 따른 효과분석으로는 제어를 통한 지체감소의 효용성 및 안전도 측면에서 각 Cell별 속도 및 밀도의 표준편차의 개선정도를 살펴보았다. 향후 본 연구의 이론적 검증 및 분석 결과를 토대로 다양한 가변속도제어모형 및 운영방안을 개발할 수 있을 것으로 예상한다.

• 품질경영학회지
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• 제32권1호
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• pp.130-143
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• 2004

Although consumer needs for better products force manufactures to put emphasis on design, often development of a product has been done without the formal process to consider consumer needs. In order to identify the implicit needs of customers and the areas of potential demand on a product, several analysis scheme such as QFD (Quality Function Deployment) has been developed. QFD, also known as the House of Quality, is the efficient tool ever created to tie product and service design decisions directly to customer wants and needs, i.e. VoC (Voice of Customer) To utilize this tool on a product design, first of all, the consumers attributes and the engineering characteristics must be exactly investigated. However there were only few studies about them on shoe design. Hence in this paper we developed an innovative framework for shoes design based on QFD. As a result, we uncovered 29 dominant human satisfaction dimensions as the consumers attributes for customer-oriented quality evaluation of a comfortable shoes. Here, 29 human satisfaction dimensions for a shoe design were identified as the dimensions that represent the human sensitivity and psychological feeling on comfortable shoes. Also, we proposed 60 human interface elements as the engineering characteristics. The relationships between human satisfaction dimensions and human interface elements were investigated. This study will help the designers and manufacturers clarify the conceptual and abstract aspect of the design evaluation by proposing a more systematic and process-oriented method.

• 웰빙융합연구
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• 제4권3호
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• pp.23-33
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• 2021

Purpose: In the course of the domestic environmental impact assessment, the current status survey was improperly conducted, and the issue of false and inaccurate environmental impact assessment reports has been raised several times recently through media reports. Research design, data and methodology: There is a continuous demand for improvement measures for the current status measurement method, such as having difficulties in securing a normal measurement date in consideration of equipment operation and rainfall days in the field. Results: In addition, in order to grasp the general air quality status of the evaluation target area, it is necessary to check the various current status concentrations by season and time series per year. However, there is a problem that is currently being carried out based on limited results such as measurement for 1 day or 3 days. Conclusions: Therefore, in this study, based on the national atmospheric measurement network, an inverse distance weighted (IDW) interpolation method was applied to calculate the current state concentration. This study suggested a method to use it in preparing the air quality item in the environmental impact assessment report.

• 대한인간공학회지
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• 제34권6호
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• pp.549-561
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• 2015

Objective: The purpose of this study was to investigate the job stress factors of mobile communication network construction workers using survey based on 'Job stress factors evaluation tool for Koreans' that was developed by KOSHA in 2003. Background: Due to the rapid growth of penetration rate of smartphone, the necessity of LTE service changing from 3G network was brought up. The demand of LTE network construction in a short period of time leads to the aggravation of the job stress of mobile communication network construction workers. Method: Two hundred and fifty workers who were in the mobile communication network industry participated in this study, and among them 206 responses were analyzed for this study due to the unreliability and insincerity of responses. The eight job stress factors which are physical environment, job demand, job autonomy, relation conflict, job instability, organizational system, inadequate compensation, workplace culture were analyzed. Results: The job stress factors of mobile communication network construction workers were compared to those of other industry workers, and other work related characteristics were analyzed. The results showed that the stress level of a physical environment and job requirement were relatively higher than those of manufacturing industry workers, meaning that mobile communication network construction workers have rough working conditions and increased amount of work due to the demand of LTE network construction. The stress level of physical environment for outdoor job workers was relatively higher than that of indoor job workers. With the analytical result for level of job satisfaction, significant difference was observed (p <0.05) with every factor, and the job stress was found the highest with those not satisfied with every factor Conclusion: From the results of this study, the work loss due to the job stress could be prevented, and accurate stress factors could be removed at the workplace. Application: The results of this study may not represent the whole mobile network construction workers, the effort for job stress management is needed to improve the work efficiency and the workers' quality of life.

• 한국경영과학회지
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• 제37권3호
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• pp.135-150
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• 2012

This paper presents a portfolio model for a long-term power generation mix problem. The proposed portfolio model evaluates generation mix by considering the tradeoffs between the expected cost for power generation and its variability. Unlike conventional portfolio models measuring variance, we introduce Conditional Value-at-Risk (CVaR) in designing the variability with aims to considering events that are enormously expensive but are rare such as nuclear power plant accidents. Further, we consider uncertainties associated with future electricity demand, fuel prices and their correlations, and capital costs for power plant investments. To obtain an objective generation by each energy source, we employ the sample average approximation method that approximates the stochastic objective function by taking the average of large sample values so that provides asymptotic convergence of optimal solutions. In addition, the method includes Monte Carlo simulation techniques in generating random samples from multivariate distributions. Applications of the proposed model and method are demonstrated through a case study of an electricity industry with nuclear, coal, oil (OCGT), and LNG (CCGT) in South Korea.

• 센서학회지
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• 제32권3호
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• pp.140-146
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• 2023

Water quality is crucial for human health and the environment. Accurate measurement of the quantity of organic carbon in water is essential for water quality evaluation, identification of water pollution sources, and appropriate implementation of water treatment measures. Total organic carbon (TOC) analysis is an important tool for this purpose. Although other methods, such as chemical oxygen demand (COD) and biochemical oxygen demand (BOD) are also used to measure organic carbon in water, they have limitations that make TOC analysis a more favorable option in certain situations. For example, COD requires the use of toxic chemicals, and BOD is time-consuming and can produce inconsistent and unreliable results. In contrast, TOC analysis is rapid and reliable, providing accurate measurements of organic carbon content in water. However, common methods for TOC analysis can be complex and energy-intensive because of the use of high-temperature heaters for liquid-to-gas phase transitions and the use of acid, which present safety risks. This study focuses on a TOC analysis method using TiO₂ photocatalysis, which has several advantages over conventional TOC analysis methods, including its low cost and easy maintenance. For TiO₂, rutile and anatase powders are mixed with an inorganic binder and spray-coated onto a glass fiber substrate. The TiO₂ powder and inorganic binder solutions are adjusted to optimize the photocatalytic reaction performance. The TiO₂ photocatalysis method is a simple and low-power approach to TOC analysis, making it a promising alternative to commonly used TOC analysis methods. This study aims to contribute to the development of more efficient and cost-effective approaches for water quality analysis and management by exploring the effectiveness and reliability of the developed equipment.

• 한국전자통신학회논문지
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• 제18권2호
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• pp.277-284
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• 2023

소규모 기업이 산재한 산업단지는 에너지 관리시스템을 구현하기가 쉽지 않아 에너지관련 데이터를 수집하여 조정하는 방법을 주로 사용한다. FEMS는 수동적 에너지 관리 방식에서 IoT와 ICT를 활용하는 능동적 에너지 관리 방식으로의 패러다임 변화 요구에 대응하는 시스템이다. 본 연구에서는 화학산업단지에 소재하고 있는 중소기업을 대상으로 공장에너지 관리시스템을 설계한다. 각 기업에 구축된 설비의 전력에너지를 대상으로 FEMS를 통하여 에너지를 절감하는 방안과 효율을 검토하여 효율성을 확인하였다. FEMS의 비용 효과성은 수용 기업의 업무 프로세스 내에서 책임과 권한이 부여된 인력에 의해 활용될 때 창출된다. 따라서 기업의 조직과 에너지 경영 목표 달성을 위한 에너지 경영 시스템의 기획, 지원, 운영 및 평가, 그리고 지속적 개선에 적용할 수 있는 EMS를 활용하는 것이 필요하다.

• 의료법학
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• 제8권2호
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• pp.167-193
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• 2007

Medical demand has been increased explosively since health insurance was introduced in 1977. Person has taken a growing interest in increase of medical service supply while that period. We must understand the legal aspects of medical quality management. There have been many legislative efforts for securing the right of patient. Patient's legal right is secured through the declaration of patient's right and all hospital person deal with patients according to the standard and criterion of the declaration of patient's right. The patient's right is set up on a basis of the right to live and the expectation right of patient. It is important to prevent medical accidents because the right of patient's health is violated by medical accident. We must manage well the medical quality to prevent the medical accident. The effort to escalate the medical quality is the best method to decrease the medical dispute. Nowadays a person take a growing interest medical quality. Our government make an effort to secure the medical quality through the legal system to be contained health organization evaluation system.

• 한국재난정보학회 논문집
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• 제18권3호
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• pp.589-599
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• 2022

연구목적: 본 연구는 수도권 도시철도 이용자에 의해 발생하는 환경 기여도를 정량적으로 파악하는데 목적이 있다. 연구방법: 분석방법은 수도권 도시철도 1~9호선을 대상으로 각 노선이 미개통되었다는 전제하에 교통수요분석의 수단선택과 통행배정을 반복 수행한 후, 공로의 전환수요에 따른 각 노선별 환경기여도를 분석하였다. 연구결과: 이산화탄소 배출량의 총량적인 측면에서는 도시철도 1호선에서 환경기여도가 가장 큰 것으로 나타났으나, 역수 및 연장을 고려할 경우, 도시철도 4호선이 가장 큰 영향을 미치는 것으로 나타났다. 결론: 대중교통 이용 증진 방안은 대표적인 환경 개선 정책이나, 실제 이를 체감하기 어렵다는 한계가 있다. 따라서 환경에 대한 인식 개선 확산을 위해 그 효과를 정량적으로 제시할 필요가 있을 것으로 판단된다.

• 한국물환경학회지
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• 제39권5호
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• pp.377-389
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• 2023

Chungcheongnam-do has been measuring the flow rate and water quality of streams in the province once a month since 2011 in order to water environment policies. Based on the results, after evaluating the coefficient of variation and the tendency of the water quality trend by using the Mann-Kendall test and Sen's Slope for each stream, the streams subject to priority introduction of Total Pollution Load Management at Tributaries were selected through the Stream Grouping Method. The water quality trend analysis results for 125 streams using the Mann-Kendall test and Sen's Slope were evaluated as streams showing a tendency of deteriorating water quality Biochemical oxygen demand (BOD): 13 streams, Total Phosphorus (T-P): 16 streams). Streams with deteriorating water quality were classified into A-D groups using the Stream Grouping Method. Group A, which has a high flow rate and high water quality, is a stream that requires priority management, and was selected as a stream for introduction of Total Pollution Load Management at Tributaries. There are 7 streams that need to be introduced into the BOD category, and there are 7 streams that need to be introduced into the T-P category. In this study, based on flow and water quality monitoring data accumulated over a long period of time (2011-2022), statistical techniques are used to select watersheds in which water quality is deteriorating. Accordingly, it is expected that it will be useful in establishing a water quality improvement plan in the future.