• Title/Summary/Keyword: Agency Problems

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Multi-Objective Design Exploration for Multidisciplinary Design Optimization Problems

  • Obayashi Shigeru;Jeong Shinkyu;Chiba Kazuhisa
    • 한국전산유체공학회:학술대회논문집
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    • 2005.10a
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    • pp.1-10
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    • 2005
  • A new approach, Multi-Objective Design Exploration (MODE), is presented to address Multidisciplinary Design Optimization (MDO) problems by CFD-CSD coupling. MODE reveals the structure of the design space from the trade-off information and visualizes it as a panorama for Decision Maker. The present form of MODE consists of Kriging Model, Adaptive Range Multi Objective Genetic Algorithms, Analysis of Variance and Self-Organizing Map. The main emphasis of this approach is visual data mining. An MDO system using high fidelity simulation codes, Navier-Stokes solver and NASTRAN, has been developed and applied to a regional-jet wing design. Because the optimization system becomes very computationally expensive, only brief exploration of the design space has been performed. However, data mining result demonstrates that design knowledge can produce a good design even from the brief design exploration.

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An LMI-based Stable Fuzzy Control System Design with Pole-Placement Constraints

  • Hong, Sung-Kyung
    • Transactions on Control, Automation and Systems Engineering
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    • v.1 no.2
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    • pp.87-93
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    • 1999
  • This paper proposes a systematic designs methodology for the Takagi-Sugeno (TS) model based fuzzy control systems with guaranteed stability and pre-specified transient performance for the application to a nonlinear magnetic bearing system. More significantly, in the proposed methodology , the control design problems which considers both stability and desired transient performance are reduced to the standard LMI problems . Therefore, solving these LMI constraints directly (not trial and error) leads to a fuzzy state-feedback controller such that the resulting fuzzy control system meets above two objectives. Simulation and experimentation results show that the proposed LMI-based design methodology yields only the maximized stability boundary but also the desired transient responses.

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Finding Alternative Solutions and Analyzing Spectrum Policy Cost on Spectrum Usage (전파사용 기반의 전파정책성 비용제도 분석 및 대안의 결정)

  • Ahn, Choon-Soo;Lee, Dong-Hyung;Youm, Se-Kyoung
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.35 no.2
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    • pp.181-188
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    • 2012
  • The fee system on spectrum usage is a usage fee that is charged for using spectrum provided by a wireless tower, and is used for management and promotion of the waves. The current fee system for spectrum usage in South Korea has faced many problems, such as complex calculation for fees, unjustified charges, unfairness in cost sharing among providers, and general inefficiency of operation. This study focuses on comparison of fee systems for spectrum usage of South Korea and other foreign countries, extraction of the root causes and problems by case analyses, and recommendation for better solutions to make a reasonable fee system for spectrum usage. The result of this study can be used as a solution to render spectrum usage more effective.

Employee Trip Reduction in Southern California : First Year Results

  • Genevieve Giuliano
    • Proceedings of the KOR-KST Conference
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    • 1993.02a
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    • pp.6-34
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    • 1993
  • Trip reduction policies are increasingly utilized in U. S metropolitan areas to address congestion and air quality problems. These policies typically focus on the journey to work and are aimed at reducing the amount of drive-alone commuting by providing transit and ridesharing incentrives. Severe air quality problems in Southern California have prompted the air polluation control agency for theLos Angeles metropolitan area to enact Regulation XV. The regulation requres employers to develop and implement a trip reduction program to achieve specified ridesharing goals. It si the most ambitious and far reaching such program implemented to date, and offers a unique opportunity to determine whether such programs can significntly affect travel behavior . This paper presents results from the first year of Regulation XV's implementation.

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The Aerodynamic Shape Optimization with Trust Region Methods (Trust Region 기법을 이용한 공력 형상 최적설계)

  • Lee, Jae-Hun;Jung, Kyung-Jin;Kwon, Jang-Hyuk
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03b
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    • pp.130-133
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    • 2008
  • In this paper the trust region method is studied and applied in aerodynamic shape optimization. The trust region method is a gradient-based optimization method, but it is not as popular as other methods in engineering computations. Its theory will be explained for unconstrained optimization problems and a trust region subproblem will be solved with the dogleg method. After verifying the trust region method with analytical test problems, it is applied to aerodynamic shape design optimization and the performance of airfoil is improved successfully.

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A study of problems&solutions of the domestic field blasting (국내 현장발파의 문제점과 해결책에 관한 고찰)

  • Jang, Hyeong-Du
    • Proceedings of the KSEE Conference
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    • 2006.10a
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    • pp.27-46
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    • 2006
  • Field blasting engineers who took a degree from university, and passed the national qualifying examination of blaster, and took a prescribed course by national commend, and got a license of blasting from the national police agency are the foundation of a society of explosive&blasting of south Korea. By their view, we want to find problems of the domestic fiend blasting, and to think about solutions. I hope they become the world's best blasting engineer.

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An Study on Measures of Regulation Reform for Disaster Reduction in Steep Slopes (급경사지 재해 경감을 위한 제도개선 방안 연구)

  • Lee, Gyeong-Ho;Yoo, Nam-Jae
    • Journal of Industrial Technology
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    • v.32 no.A
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    • pp.71-78
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    • 2012
  • In this paper, reviews and analyses of literatures related to characteristics and status of disaster occurrence in steep slopes in Korea, its maintenance and regulations and laws about maintenance of slopes in abroad were carried out to propose the measures of regulation reform for disaster reduction in steep slopes. The regulation on disaster prevention in steep slopes (National Emergency Management Agency, 2007), the most effective and systematically arranged regulation out of the currently practicing regulations, was introduced to understand the overall and contents of this regulation. Therefore, problems related to disaster reduction in steep slopes from institutional, technical and financial points of view respectively were raised and their improving measures were proposed to treat the problems effectively and actively.

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Physical Health Problems and Life Satisfaction among Alcoholics: Moderating Effects of Religions Coping (알코올중독자의 신체적 건강과 삶의 만족도: 종교적 대처의 완충효과)

  • Lee, Bong-Jae;Oh, Yun-Jin
    • Journal of the Korean Home Economics Association
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    • v.46 no.1
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    • pp.15-24
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    • 2008
  • Although the relationship between physical health problems and life satisfaction is well documented, less is known about the role of coping strategies, in particular strategies for coping via religious or spiritual means. To investigate the relationships among these factors, data collected with questionnaires completed by 326 adult alcoholics at a rehabilitation agency. Significant Physical Health Problem $\times$ Religious Coping buffer interactions were found in the relationship between physical health problem and life satisfaction. Moderated regression analysis showed that religious coping reduced the impact of physical health problem on life satisfaction. Implications for practice are discussed.

Ergonomic Verification of Suitability of the 4-Wheeled Hand Cart to Transfer a Projectile for Towed Howitzer (견인곡사포용 이동대차형 포탄 이송장치의 인간공학적 적합성 검증)

  • Park, Sung Ho
    • Journal of Korean Institute of Industrial Engineers
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    • v.42 no.3
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    • pp.165-172
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    • 2016
  • The purpose of this study is to investigate the ergonomic verification of suitability of the 4-wheeled hand cart to prevent musculoskeletal problems in the firing test range. Because of the increasing amount of firing test, the needs to develop a projectile transferring device such as 4-wheeled hand cart has been increased. For the 4-wheeled hand cart, the lifting and carrying activity in the manual handling method were transformed to pushing activity. The risk of low back pain for lifting and carrying the projectile by manual was estimated by NLE and 3D SSPP. On the other hand, the risk for pushing the 4-wheeled hand cart was estimated by psychophysical and biomechanical method such as Mital's equation, Snook's table and 3D SSPP. It was shown that the 4-wheeled hand cart reduced the risk of low back pain drastically with higher efficiency and design compatibility.

Regulatory Problems in Radionuclide Therapy and Suggestions for Systematic Improvement (방사성동위원소 치료의 제도적 문제점과 개선)

  • Jeong, Jae-Min
    • Nuclear Medicine and Molecular Imaging
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    • v.40 no.2
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    • pp.53-57
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    • 2006
  • Radionuclide therapy has been used for more than 50 years and proved to be a safe and effective modality. However, the patients' right to have the excellent medical service is seriously disturbed by excessive regulations of government institutions such as Korea Institute of Nuclear Safety (KINS), Health Insurance Review Agency (HIRA) and Korea Food and Drug Administration (KFDA). For example, the patients should wait for more than 6 months to have I-131 treatment in many hospitals it is strongly recommended to mitigate the regulations to resonable levels to solve the problems. If HIRA allow the hospitals to charge reasonable rate for radionuclide therapy room, then more hospitals would invest to build the radionuclide therapy rooms and the patients' waiting time would decrease. The waiting time would also decrease, if KINS allow 2 patients to share a radionuclide therapy room. Finally, it is strongly recommended to lower the threshold for approval of new therapeutic radiopharmaceuticals by KFDA, which would allow new effective therapeutic raoiopharmaceuticals to be introduced to clinical practices more easily.