• Title/Summary/Keyword: System Level Design

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Improving R&D Management System through Researchers′ Satisfaction Analysis, with Special Reference to Industrial R&D Institutes (연구원 만족도 분석을 통한 연구개발 관리제도의 개선 - 산업계 연구기관을 중심으로 -)

  • 김계수;이민형
    • Journal of Korea Technology Innovation Society
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    • v.1 no.3
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    • pp.299-312
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    • 1998
  • This paper explores the possibility of improving R&D management system through researchers' satisfaction analysis. The relationship between job satisfaction and performance has traditionally been one of the engaging topics in organization psychology. However, the research results of the past showed the relatively low level of correlation between satisfaction and performance at the individual level. In contrast to these past research results, recent research results on this relationship at the organizational level revealed the higher correlation between these two factors, The present study extends this 'satisfaction and performance' hypothesis to the development and improvement of R&D management system. That is, we used the results of researchers' satisfaction analysis to devise appropriate criteria for the design and implementation of more effective R&D management systems. This paper seeks to show that we can make fruitful use of researchers' satisfaction analysis in order to choose a more effective one among alternative R&D management systems.

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Hierarchical Petri netting for design and supervision of an automated vehicle system

  • Sakai, Y.;Kitazawa, M.;Nakamura, M.;Matsuda, N.
    • 제어로봇시스템학회:학술대회논문집
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    • 1994.10a
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    • pp.763-768
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    • 1994
  • A hierarchical Petri- net is utilized in supervising an automated vehicle system, The supervisory system is supported by computer networking in order to facilitate necessary processing, and consists of control flow level and computer allocation level so that a designer and an operator can easily build and/or access to each level. There are two modes of utilizing Petri net here in this paper. One is to employ it in designing the control system, in order to optimally allocate computers in every stage of processing. The other is for supervision of the system in operation, in order for the operator to be in a easy-to-comprehend environment of operation. The effect of these two modes of utilizing Petri net is examined.

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Design of EMI filters for an Induction Motor Drive System with Multi-level inverters (멀티레벨 인버터를 이용한 3상 유도전동기 구동 시스템의 EMI 필터 설계)

  • Kim, Soo-Hong;Ahn, Young-Oh;Bang, Sang-Seok;Kim, Kwang-Seob;Kim, Yoon-Ho
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.55 no.5
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    • pp.265-270
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    • 2006
  • In this paper EMI problems with induction motor drive system using multi-level inverters are investigated. The high power multi-level inverter usually operates with low switching frequency and produces large noises. Generally, EMI consists of the conduction component through source lines and emission component emitted to the space. This conduction component can be classified to the common-mode between source line and ground, and the normal-mode between lines. The EMI filters for the induction motor drive system are designed and implemented to reduce EMI noise. Finally the designed system is verified by the experiment. The experimental results show that both the normal mode and common mode noises are greatly reduced compared to the system without filters.

Noise Characteristics of the HVAC System of Korea High Speed Train (한국형 고속전철 공조시스템 소음에 관한 연구)

  • 하인수;박철희;이우식;한기흥
    • Proceedings of the KSR Conference
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    • 1998.11a
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    • pp.379-387
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    • 1998
  • HVAC systems are used to maintain comfort conditions in occupied spaces. Like rolling noise and aerodynamic noise, noise from the HVAC system of train increases interior noise level. For an appropriate interior noise level, it is necessary not to find noise sources and their propagation paths. Noise emission from the sources and propagation through the propagation paths should be regulated in order to reduce their effect to the interior noise level. In general, the main noise source in the HVAC system is blower which operates at high static pressure. This noise propagates through ducts which are directly connected to the residential area. Since the blower noise can be reduced only to some degree, it is necessary for the propagation paths to have enough noise attenuation. Acoustic properties of ducts are usually found by experimental methods but it is rather difficult and expensive to set up such test equipments. In this thesis, the design and the noise characteristics of TGV-K HVAC system are studied. Finite element method in accordance with experimental method is used to study the acoustic properties of TGV-K duct system.

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Function Decomposition of Structural Part in Automatic Transmission Lever for the Development of Intelligent Product Design System (지능형 제품설계 시스템 개발을 위한 자동변속기 레버 구조부의 기능분해)

  • 하상도;김원기;고희병;차성운
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2001.04a
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    • pp.622-626
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    • 2001
  • Every design activity has a goal of satisfying a set of functional requirement. The commencement of a design, therefore, must have its foundation upon the identification of the functional requirements. Many of the design practices of the industrial examples can be categorized as design of small systems that are defined to have limited and fixed sets of functional requirements to be satisfied at all times. In the case of small systems it facilitates the construction of a knowledge-based system for a specific purpose to decompose the functional requirement and map ones in the lowest level into specific design features. When the number of design features is large, they need to be managed by groups. This paper suggests a grouping method for design process can be regarded as a series of selections of the predefined functional primitives according to the requirements and the preceding selections. An intelligent product design system for automatic transmission lever design is developed as an example.

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The Optimal Design for Noise Reduction of the Intake System in Automobile Using Kriging Model (크리깅을 이용한 자동차 흡기계의 소음 저감에 대한 최적 설계)

  • Sim Hyoun-Jin;Ryu Je-Seon;Cha Kyung-Joon;Oh Jae-Eung
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.4 s.247
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    • pp.465-472
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    • 2006
  • Recently, the regulations of the government and the concerns of people have rise to the interest in noise pollution levels as compared to other vehicles. In this area, many researchers have studied to reduce this noise in the field of automotive engineering. This paper proposes an optimal design scheme to reduce the noise of the intake system by adapting Kriging with two meta-heuristic techniques. For this, as a measuring tool for the performance of the intake system, the performance prediction software, was used. Then, the length and radius of each component of the current intake system are selected as input variables and the orthogonal arrays is adapted as a space-filling design. With these simulated data, we can estimate a correlation parameter in Kriging by solving the nonlinear problem with a genetic algorithm and find an optimal level for the intake system by optimizing Kriging estimated with simulated annealing. We notice that this optimal design scheme gives noticeable results and is a preferable way to analyze the intake system. Therefore, an optimal design for the intake system is proposed by reducing the noise of its system.

End-to-end system level modeling and simulation for medium-voltage DC electric ship power systems

  • Zhu, Wanlu;Shi, Jian;Abdelwahed, Sherif
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.10 no.1
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    • pp.37-47
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    • 2018
  • Dynamic simulation is critical for electrical ship studies as it obtains the necessary information to capture and characterize system performance over the range of system operations and dynamic events such as disturbances or contingencies. However, modeling and simulation of the interactive electrical and mechanical dynamics involves setting up and solving system equations in time-domain that is typically time consuming and computationally expensive. Accurate assessment of system dynamic behaviors of interest without excessive computational overhead has become a serious concern and challenge for practical application of electrical ship design, analysis, optimization and control. This paper aims to develop a systematic approach to classify the sophisticated dynamic phenomenon encountered in electrical ship modeling and simulation practices based on the design intention and the time scale of interest. Then a novel, comprehensive, coherent, and end-to-end mathematical modeling and simulation approach has been developed for the latest Medium Voltage Direct Current (MVDC) Shipboard Power System (SPS) with the objective to effectively and efficiently capture the system behavior for ship-wide system-level studies. The accuracy and computation efficiency of the proposed approach has been evaluated and validated within the time frame of interest in the cast studies. The significance and the potential application of the proposed modeling and simulation approach are also discussed.

A Design Scheme of Online Test and Evaluation System (온라인 시험 및 평가 시스템 설계 방안)

  • Choi, Kyungsoo;Lee, Kilhung
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.13 no.1
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    • pp.13-21
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    • 2017
  • This paper describes a design scheme of a system that tests or polls from the students at online class. By online test, the teacher can test the pre-knowledge level of the students and know how much students understand the lecture of the class. As the number of test increases, the burden of the preparation of setting question, evaluation of the test, and management of the test results is increased. In this environments, an online test management system make it easy to test and evaluate, and thus it would be a good tool for maintaining and managing the total procedure of the test or poll of the students. For evaluating the design of the system, we made a test system prototype and performed evaluations of the online test system. The online test and evaluation system provides a good tool for testing and evaluation of student's knowledge at the class with easy and fast way.

A comparative study on the initial stability of different implants placed above the bone level using resonance frequency analysis

  • Kang, In-Ho;Kim, Chang-Whe;Lim, Young-Jun;Kim, Myung-Joo
    • The Journal of Advanced Prosthodontics
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    • v.3 no.4
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    • pp.190-195
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    • 2011
  • PURPOSE. This study evaluated the initial stability of different implants placed above the bone level in different types of bone. MATERIALS AND METHODS. As described by Lekholm and Zarb, cortical layers of bovine bone specimens were trimmed to a thickness of 2 mm, 1 mm or totally removed to reproduce bone types II, III, and IV respectively. Three Implant system (Br${\aa}$nemark System$^{(R)}$ Mk III TiUnite$^{TM}$, Straumann Standard Implant SLA$^{(R)}$, and Astra Tech Microthread$^{TM}$-OsseoSpeed$^{TM}$) were tested. Control group implants were placed in level with the bone, while test group implants were placed 1, 2, 3, and 4 mm above the bone level. Initial stability was evaluated by resonance frequency analysis. Data was statistically analyzed by one-way analysis of variance in confidence level of 95%. The effective implant length and the Implant Stability Quotient (ISQ) were compared using simple linear regression analysis. RESULTS. In the control group, there was a significant difference in the ISQ values of the 3 implants in bone types III and IV (P<.05). The ISQ values of each implant decreased with increased effective implant length in all types of bone. In type II bone, the decrease in ISQ value per 1-mm increase in effective implant length of the Br${\aa}$nemark and Astra implants was less than that of the Straumann implant. In bone types III and IV, this value in the Astra implant was less than that in the other 2 implants. CONCLUSION. The initial stability was much affected by the implant design in bone types III, IV and the implant design such as the short pitch interval was beneficial to the initial stability of implants placed above the bone level.

Study on design of computer maintenance & repair system using SLA technique (SLA 기법을 활용한 컴퓨터 유지보수 시스템 설계에 관한 연구)

  • 김성선;최용식;신승호
    • Journal of the Korea Society of Computer and Information
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    • v.9 no.2
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    • pp.63-68
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    • 2004
  • In this study We designed development and operation of computer maintenance & repair system which is efficient and systematic on the disorder of PC in the places with many computers such as company, public organization, school, etc. We designed so as to clearly measure and manage the service level by using SLA(Service Level Agreement) technique which is being used actively in network maintenance & repair contract And We designed system which can provide One Stop Service so that the whole process of service including service demand point, maintenance & repair activity, user's satisfaction.

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