• Title/Summary/Keyword: complex system

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System Integration Test Design to Ensure Reliability of Complex Guided Missile System (복합 유도무기체계의 신뢰성 확보를 위한 체계 통합 시험 설계)

  • Hwang, Ho-Sung;Jo, Kyoung-Hwan;Park, In-Chul;Yun, Won-Sik
    • Journal of Applied Reliability
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    • v.12 no.2
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    • pp.105-119
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    • 2012
  • In this paper, we have proposed a methodology which can make effective test for system integration of complex guided missile system. System integration test play a significant role in the development of weapon system, providing the means to detect and isolate faults on first linkage between sub-systems. Integration tests for domestic weapon system has executed not a technology-intensive method based on tool but labor-intensive method based on experience. Higher cost, longer period, and more resource are required to execute system integration test for complex guided missile system comparing with past weapon systems, because recently weapon systems have more complex and more networked functions. Because the proposed design method for system integration test decreases number of test case, it lead to a decrease of cost, period, and resource for integration test of weapon system. The proposed configuration for system integration test will ensure reliability through detection and isolation of fault on linkage between sub-systems.

Centroidal Voronoi Tessellation-Based Reduced-Order Modeling of Navier-Stokes Equations

  • 이형천
    • Proceedings of the Korean Society of Computational and Applied Mathematics Conference
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    • 2003.09a
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    • pp.1-1
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    • 2003
  • In this talk, a reduced-order modeling methodology based on centroidal Voronoi tessellations (CVT's)is introduced. CVT's are special Voronoi tessellations for which the generators of the Voronoi diagram are also the centers of mass (means) of the corresponding Voronoi cells. The discrete data sets, CVT's are closely related to the h-means clustering techniques. Even with the use of good mesh generators, discretization schemes, and solution algorithms, the computational simulation of complex, turbulent, or chaotic systems still remains a formidable endeavor. For example, typical finite element codes may require many thousands of degrees of freedom for the accurate simulation of fluid flows. The situation is even worse for optimization problems for which multiple solutions of the complex state system are usually required or in feedback control problems for which real-time solutions of the complex state system are needed. There hava been many studies devoted to the development, testing, and use of reduced-order models for complex systems such as unsteady fluid flows. The types of reduced-ordered models that we study are those attempt to determine accurate approximate solutions of a complex system using very few degrees of freedom. To do so, such models have to use basis functions that are in some way intimately connected to the problem being approximated. Once a very low-dimensional reduced basis has been determined, one can employ it to solve the complex system by applying, e.g., a Galerkin method. In general, reduced bases are globally supported so that the discrete systems are dense; however, if the reduced basis is of very low dimension, one does not care about the lack of sparsity in the discrete system. A discussion of reduced-ordering modeling for complex systems such as fluid flows is given to provide a context for the application of reduced-order bases. Then, detailed descriptions of CVT-based reduced-order bases and how they can be constructed of complex systems are given. Subsequently, some concrete incompressible flow examples are used to illustrate the construction and use of CVT-based reduced-order bases. The CVT-based reduced-order modeling methodology is shown to be effective for these examples and is also shown to be inexpensive to apply compared to other reduced-order methods.

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An Investigative Study on the Structural Characteristics of High-Rise Complexes in Korea (국내 고층 주상복합 건물의 구조적 특성에 관한 조사 연구)

  • Kang Suk-Won;Lee Sung-Ho
    • Korean Journal of Construction Engineering and Management
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    • v.4 no.4 s.16
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    • pp.137-144
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    • 2003
  • Recently, the interest in a complex building increases rapidly in Korea. High-rise complex is not simply the combination of a residential apartment and a business office as previous but a building with the object of the convenience of the residents familiar with city-life style through adapting the high class life style and new residential culture to the business space, and the efficiency in using the limited building site in the town. This study presents an exploratory analysis focusing the structural system with the help of the extensive survey of the construction site in Korea, and aims a guideline for the structural design and construction of high rise complex. Through the survey, change and development in the design and the construction can be seen as the height and size of the complex grow. It is almost indispensable to design a structural system against lateral forces like earthquake or wind, which is usually measured by story drift ratio or story displacement. Improvement of the structural materials and their usages is also included for the efficiency of the structural system. Useful slab-beam system contributing to the decrease of the story height is still a concern.

On the Effect of a Pilot Coding Education Support System for Complex Problem Solving Tasks

  • Jeon, Inseong;Song, Ki-Sang
    • International journal of advanced smart convergence
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    • v.7 no.4
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    • pp.128-137
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    • 2018
  • In the programming education, there is a great need of a teaching support system that can support the learner in the programming process regardless of the computer language due to instructor's difficulty of checking the progress of learners in real-time. Its importance is especially important in lower grade coding classes such as in K-12 education because they are not used to coding and so simple problems can be regarded as complex problems. For this, a pilot coding education support system based on Levenshtein distance algorithm which shows learners' progress to given solution in real-time was developed in order to help learners to solve complex problems easily, and the learners' motivation and self-efficacy was measured for estimating the usefulness of developed system targeting elementary school students. When the learners use the developed system, it was found that a statistically significant difference appears in the sub-factors of learning motivation compared with traditional class teaching environments. Among the sub-factors of self-efficacy, the efficacy dimension showed statistically significant difference too.

DEVELOPMENT OF INFORMATION FLOW RETRIEVAL SYSTEM FOR LARGE-SCALE AND COMPLEX CONSTRUCTION PROJECTS

  • Jinho Shin;Hyun-soo Lee;Moonseo Park;Kwonsik Song
    • International conference on construction engineering and project management
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    • 2013.01a
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    • pp.648-651
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    • 2013
  • The information generated in large-scale and complex construction projects are transferred continuously and transformed into project products on the long span life cycle. Therefore, information flow management is related with the success of project directly. However, certain characteristics of large-scale and complex construction projects make the solving the problem more difficultly. Although several information retrieval systems support the information management system, it is not suitable to grasp information flows. Hence, we developed an information retrieval system specialized with the information flow based on a preceding research. The system consists of a relation-based database and the process information transferring relation inference application module. The system enables project managers to manage the entire project process more efficiently and each project member to work their own task being served the information flow retrieval results.

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Influence of Pressure Reducing Valves on Flow Characteristics of the Water Supply System for an Apartment Complex (공동주택단지 급수계통의 유량특성에 미치는 감압밸브의 영향)

  • Kim, Tae Jin;Cha, Dong Jin
    • KIEAE Journal
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    • v.12 no.6
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    • pp.23-28
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    • 2012
  • Pressure distribution in the water supply system of an apartment complex consisting of 12 buildings and 635 units in total have been investigated numerically. The complex incorporates two zone booster pump system, and around a half of units have pressure reducing valves (PRVs) in them. Calculated hydrostatic pressure without the water flow were compared with their designed and measured counterparts, and they agreed quite well with each other. Then, the pressure and volumetric water flow rate at all units were analyzed, indicating that there are noticeable differences in pressure and flow rate in one unit to another, although the aforementioned minimization technologies of pressure deviation were employed. In order to further reduce the difference in the water flow rate, it is suggested that all the units in the complex have PRVs installed in their water supply system. The effect of setting pressure of the PRVs on the non-uniformity of the flow in each unit and on the reduction of total water supply for the apartment complex have been studied. With the same PRV setting pressure of 3.952 bar (or the gauge pressure of $3.0kg_f/cm^2$), it has been estimated that the suggested system improves the non-uniformity (the coefficient of variation) of the flow rate of apartment complex over the current system, from 8.02% to 6.66%, and reduces the total water supply, from $0.02804m^3/s$ to $0.02766m^3/s$.

On Line Fault Diagnosis in the Large Power System (온라인 전력계통 고장 진단 시스템 개발)

  • Kim Jung-Nyun;Baek Sik-Young;Seo Gyul-Seok
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.54 no.5
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    • pp.205-211
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    • 2005
  • Recently, power system is getting larger and more complex. When the complex power system has a problem, it is very difficult even for the experts to find out where the problem is and to make a timely decision by operators. There have been many studies on these problems but the results are not good enough for applying to real power system. Therefore, power system operators always had to judge the exact state of power system and be preparative for the problems that can occur later. We developed new methods that can be applied to complex power system by dividing the system into small modules. By using 'module', we can combine small modules together to make complex power systems and the knowledge base that is applied to fault diagnosis system. As a result, compared to previously developed diagnosis products, operation time is shortened and the knowledge base is become simpler and clearer, which made online usage capable. This system can be used as a complementary measurement that helps the operator from making any mistakes.

A Study on Design Method of Underground Space based on MPAM Theory (MPAM 이론에 의한 지하공간의 설계방법 연구)

  • Lee Wan-jae;Kim Tae-Hong
    • 한국터널공학회:학술대회논문집
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    • 2005.04a
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    • pp.87-104
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    • 2005
  • Rock masses represent natural systems that are inherently complex and in which multiple mechanisms occur. Rock engineering systems such as tunnel and slope interact with surrounding systems through an exchange of both mass and energy. Accordingly the complex nature of rock masses calls for a system approach, and the open nature of rock engineering even requires the engineering to be controlled by a system approach for surrounding environments. However, traditional methods cannot take all variables and their interactions into account and are limited to the system with single mechanisms. Therefore, they are not proper for a complex and open system, and also cannot portray the whole system. Thus, a system approach is indispensable to rock engineering for dealing with the whole of a complex and open system. In this paper Mechanism Path Analysis Methodology (MPAM) Is Introduced for a system approach to rock engineering. The analysis by the methodology gives us all the information of systems behavior in the context of the whole system in order to accomplish the optimum design in accordance with the project objectives and analysis purposes. As an application a conventional model for the evaluation of TBM tunneling performance system is analyzed by MPAM and the result is compared with that by a traditional method.

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Main Control System of Propulsion System Test Complex(PSTC) for KSLV-II (한국형발사체 추진기관시스템 시험설비(PSTC) 통합제어시스템)

  • Kim, Dongki;Lee, Jungho;Cho, Kiejoo;Shim, Juyoung
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2017.05a
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    • pp.1205-1211
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    • 2017
  • The Propulsion System Test Complex(PSTC) was constructed for the verification test of each stage's propulsion system of KSLV-II. Main Control System(MCS) is the system to operate the onboard equipment and the ground equipment of the PSTC simultaneously. This paper describes the critical design, the development status, and test results of Main Control System. The MCS will be used for the interface connection between ground control systems and onboard equipment. Test sequence and operation process of the Work Manager will be conducted by MCS.

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New Yeast Cell-Based Assay System for Screening Histone Deacetylase 1 Complex Disruptor

  • Jeon, Kwon-Ho;Kim, Min-Jung;Kim, Seung-Young
    • Journal of Microbiology and Biotechnology
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    • v.12 no.2
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    • pp.286-291
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    • 2002
  • Histone deacetylase I (HDAC1) works as one of the components in a nucleosome remodeling (NuRD) complex that consists of several proteins, including metastasis-associated protein 1 (MTA1). Since the protein-protein interaction of HDAC1 and MTA1 would appear to be important for both the integrity and functionality of the HDAC1 complex, the interruption of the HDAC1 and MTA1 interaction may be an efficient way to regulate the biological function of the HDAC1 complex. Based on this idea, a yeast two-hybrid system was constructed with HDAC1 and MTA1 expressing vectors in the DNA binding and activation domains, respectively. To verify the efficiency of the assay system, 3,500 microbial metabolite libraries were tested using the paper disc method, and KB0699 was found to inhibit the HDAC1 and MTA1 interaction without any toxicity to the wild-type yeast. Furthermore, KB0699 blocked the interaction of HDAC1 and MTA1 in an in vitro GST pull down assay and induced morphological changes in B16/BL6 melanoma cells, indicating the interruption of the HDAC1 complex function. Accordingly, these results demonstrated that the yeast assay strain developed in this study could be a valuable tool for the isolation of a HDAC1 complex disruptor.