• 제목/요약/키워드: Utility Work

검색결과 287건 처리시간 0.023초

Sequencing the Mixed Model Assembly Line with Multiple Stations to Minimize the Total Utility Work and Idle Time

  • Kim, Yearnmin;Choi, Won-Joon
    • Industrial Engineering and Management Systems
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    • 제15권1호
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    • pp.1-10
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    • 2016
  • This paper presents a fast sequencing algorithm for a mixed model assembly line with multiple workstations which minimize the total utility work and idle time. We compare the proposed algorithms with another heuristic, the Tsai-based heuristic, for a sequencing problem that minimizes the total utility works. Numerical experiments are used to evaluate the performance and effectiveness of the proposed algorithm. The Tsai-based heuristic performs best in terms of utility work, but the fast sequencing algorithm performs well for both utility work and idle time. However, the computational complexity of the fast sequencing algorithm is O (KN) while the Tsai-based algorithm is O (KNlogN). Actual computational time of the fast sequencing heuristic is 2-6 times faster than that of the Tsai-based heuristic.

자동차 조립라인에서 총 가외작업을 최소로 하는 투입순서 결정 (Sequencing to Minimize the Total Utility Work in Car Assembly Lines)

  • 현철주
    • 대한안전경영과학회지
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    • 제5권1호
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    • pp.69-82
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    • 2003
  • The sequence which minimizes overall utility work in car assembly lines reduces the cycle time, the number of utility workers, and the risk of conveyor stopping. This study suggests mathematical formulation of the sequencing problem to minimize overall utility work, and present a genetic algorithm which can provide a near optimal solution in real time. To apply a genetic algorithm to the sequencing problem in car assembly lines, the representation, selection methods, and genetic parameters are studied. Experiments are carried out to compare selection methods such as roullette wheel selection, tournament selection and ranking selection. Experimental results show that ranking selection method outperforms the others in solution quality, whereas tournament selection provides the best performance in computation time.

Antioxidant Activity of Some Yogurt Starter Cultures

  • Kim, H.S.;Chae, H.S.;Jeong, S.G.;Ham, J.S.;Im, S.K.;Ahn, C.N.;Lee, J.M.
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권2호
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    • pp.255-258
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    • 2005
  • Several commercial yogurt starter cultures (L. acidophilus LA5, L. casei 01, L. acidophilus LA100, L. bulgaricus LB207 and L. rhamnosus GG744) were investigated for antioxidant activity by using in vitro assays. From the results of the present work, all strains tested showed varying degrees of antioxidant activity. L. bulgaricus LB207 showed the highest antioxidant activity, with a linoleic acid peroxidation inhibition of 81.3%. Hydroxy radical scavenging activity, ferrous iron chelating activity, reducing power and superoxide dismutase (SOD) activity were also studied. L. bulgaricus LB207 showed the highest hydroxy radical scavenging activity and L. casei 01 showed the highest chelating activity. L. bulgaricus LB207 and L. acidophilus LA100 showed good reducing power. All the strains in this study showed low SOD activity. The results of the present work suggest that antioxidant activity of L. bulgaricus LB207 due to its strong hydroxy radical scavenging activity and reducing power.

Utility Bounds of Joint Congestion and Medium Access Control for CSMA based Wireless Networks

  • Wang, Tao;Yao, Zheng;Zhang, Baoxian;Li, Cheng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권1호
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    • pp.193-214
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    • 2017
  • In this paper, we study the problem of network utility maximization in a CSMA based multi-hop wireless network. Existing work in this aspect typically adopted continuous time Markov model for performance modelling, which fails to consider the channel conflict impact in actual CSMA networks. To maximize the utility of a CSMA based wireless network with channel conflict, in this paper, we first model its weighted network capacity (i.e., network capacity weighted by link queue length) and then propose a distributed link scheduling algorithm, called CSMA based Maximal-Weight Scheduling (C-MWS), to maximize the weighted network capacity. We derive the upper and lower bounds of network utility based on C-MWS. The derived bounds can help us to tune the C-MWS parameters for C-MWS to work in a distributed wireless network. Simulation results show that the joint optimization based on C-MWS can achieve near-optimal network utility when appropriate algorithm parameters are chosen and also show that the derived utility upper bound is very tight.

가정과 교육내용의 유용성 인지에 관한 연구 -중학교 ‘가족과 일의 이해’ 단원을 중심으로 - (A study on students′ utility cognition of Home Economics course)

  • 지금수;이진숙
    • 한국가정과교육학회지
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    • 제14권3호
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    • pp.77-88
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    • 2002
  • This study was designed to examine students' utility cognition and related variables on the ‘understanding of family and work’ in the Home Economics course. The subjects were 503 middle and high school students, and university students in Jeonju city. The results are as follows : 1) The level of utility cognition on the ‘attitude of sexuality’ was found to be relatively high in the Home Economics course. 2) There were gender difference in the evaluation of learning environment. and grade differences in the evaluation of learning environment, participation in class of Home Economics, needs for Home Economics, evaluation of learning environment. 3) The utility cognition of Home Economics course significantly differed by gender, participation in class of Home Economics. needs for Home Economics, evaluation of learning environment. and Perception of Home Economics. 4) The needs for Home Economics emerged as the most important variable in the utility cognition of Home Economics course.

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Implementation of MPEG-21 DIA Utility Software for Stereoscopic Video Adaptation

  • Kwon Hyukmin;Kim Manbae
    • 방송공학회논문지
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    • 제10권2호
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    • pp.139-148
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    • 2005
  • This paper presents recent works of the development of MPEG-21 DIA utility software as one of MPEG-21 activities. The main purpose of this work is to make integrated utility software for DIA C/C++ modules in a Java framework. To do this, JNI plays a role of the interface of a main module with C/C++ DIA adaptation modules. Furthermore, DIA and DID parsers are integrated to the utility software. Our software is designed such that all DIA modules are easily integrated. A variety of adaptation modules have been adopted in MPEG-21 standard. Among them, stereoscopic video conversion that is one of DIA adaptation modules is chosen and we show that our utility software is correctly implemented based on experiments.

지하공동구의 체계적인 통제 및 이력관리를 위한 자동개폐시스템에 대한 연구 (A Study on Automatic Switch Control System for Systematic Control and History Management of Underground Utility Tunnel Work)

  • 오암석
    • 한국정보통신학회논문지
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    • 제19권6호
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    • pp.1443-1448
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    • 2015
  • 현재 대부분의 지하공동구 출입관리시스템은 중앙시스템과 자동개폐기 간 네트워크가 유선 상으로 구축되어 있으며, 네트워크 인프라의 부재 그리고 리더기의 야외 노출 등 지하공동구의 특수한 환경에서의 문제점들이 노출되어 있다. 이에 본 논문에서는 지하공동구의 출입관리에 대한 문제점들을 파악하고 이를 해결하기 위해 지하공동구의 특수 환경에 적합하며, 체계적인 출입 및 점검 이력의 관리가 가능한 스마트 폰 인증키 기반 지하공동구 출입관리시스템을 제안한다. 제안한 출입관리시스템은 현장 네트워크의 별도 통신망 구축 없이 스마트폰에서 지원하는 블루투스를 사용하여 출입이 가능하며 아울러, 모든 개폐기의 제어 정보를 스마트폰 애플리케이션을 통하여 서버로 전송하여 서버에서의 체계적인 통제 및 이력관리가 가능하다.

분야별 전문간호사의 전문간호업무에 대한 성과 평가: 일개 병원을 중심으로 (Evaluation of Nursing Outcomes among Advanced Practice Nurses in a Tertiary Hospital)

  • 설미이;이명선
    • 중환자간호학회지
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    • 제5권2호
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    • pp.37-48
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    • 2012
  • Purpose: The purpose of the study was to evaluate how advanced practice nurses (APNs) recognized their work by analyzing nursing outcomes. The ultimate goal was to examine the utility of APNs by connecting their work to the outcomes. Methods: Cross-sectional survey was conducted to collect the data from 59 APNs in a tertiary hospital lovated in Seoul, Korea. The questionnaire with 84 outcome indicators for advanced practice nurses was used. Descriptive statistics were used to analyze the data. Results: Among 84 outcome indicators, 11 indicators were associated with the work of APNs. Majority of these findings were included in the categories of clinical results and satisfaction. Items identified to be associated with the work of APNs were different among oncology nursing area, surgical speciality area, emergency care area, and critical care area. Conclusion: The results of the study indicated that the works of APNs were relevant to education/counseling/training and interpersonal relationship with other health professionals. The results of the study could be helpful to delineate the work characteristics of APNs and increase the utility of APNs in Korea where roles of APNs are not yet clearly delineated in most clinical settings.

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주방의 조리 공간 및 조리 기구의 사용자-만족도 측정 - 한.미 비교를 중심으로 - (Use-Utility of Kitchen Center and Cooking Equipments - Comparison between U.S.A. and Korea -)

  • 정영숙;박영선
    • 동아시아식생활학회지
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    • 제19권6호
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    • pp.1039-1048
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    • 2009
  • The purpose of this study was to establish a model of the use-utility of cooking equipments and kitchen centers using survey data and to compare U.S.A. with Korea. The survey was conducted to identify attributes that were related to the efficiency of kitchen centers as well as equipments. Indices for the most important attributes were developed and used to compare different selections of equipment. The impact of adding an equipment item was found to vary with the attributes of the item, the degree of importance ascribed to the attributes of the work center and specific functions performed there. Similarities and differences between the U.S.A. and Korea are discussed, and implications for those who have interest in the use-utility model of cooking equipment and kitchen centers are provided.

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도로시설 재굴착 방지를 위한 의사결정모델 및 관리시스템 개발 (Development of Decision Model and Management System to minimize Pavement Utility Cut for Road Facility)

  • 조진영;장운성;이민재
    • 한국건설관리학회논문집
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    • 제14권4호
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    • pp.164-171
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    • 2013
  • 도시개발에 있어 도로의 건설은 교통의 목적 외에 전기, 가스, 통신, 난방, 하수, 상수, 오수 등의 도시 편의시설을 위한 공간으로도 활용되고 있다. 하지만 현재 도로 시공과정에서 각 기능에 따른 관련 주체들이 진행되는 공사수행일정에 대한 의사소통이 충분히 이루어지지 않아 재굴착 작업이 빈번히 이루어지고 있으며 이로 인해 예산의 중복투입, 공사기간 지연, 품질저하, 이용자의 불편 등 여러 가지 문제점들이 나타나고 있다. 본 연구에서는 신도시 개발과 같은 대규모의 프로젝트에서 도로 재굴착으로 인한 문제를 사전에 예방하기 위해 시간과 공간데이터를 활용한 재굴착 방지 프로세스 모델을 개발하였으며, 이를 활용하여 도시기반시설 건설주체간 원활한 협의를 돕기 위한 재굴착방지시스템을 개발하였다. 아울러, 개발된 시스템을 개발중인 신도시 건설사업에 활용하여 그 적용성을 검토하였다.