• 제목/요약/키워드: Integration processes

검색결과 665건 처리시간 0.034초

상태변수를 갖는 비탄성 구성식 적분법의 일반화 (Generalization of Integration Methods for Complex Inelastic Constitutive Equations with State Variables)

  • 윤삼손;이순복;김종범;이형연;유봉
    • 대한기계학회논문집A
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    • 제24권5호
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    • pp.1075-1083
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    • 2000
  • The prediction of the inelastic behavior of the structure is an essential part of reliability assessment procedure, because most of the failures are induced by the inelastic deformation, such as creep and plastic deformation. During decades, there has been much progress in understanding of the inelastic behavior of the materials and a lot of inelastic constitutive equations have been developed. These equations consist of the definition of inelastic strain and the evolution of the state variables introduced to quantify the irreversible processes occurred in the material. With respect to the definition of the inelastic strain, the inelastic constitutive models can be categorized into elastoplastic model, unified viscoplastic model and separated viscoplastic model and the different integration methods have been applied to each category. In the present investigation, the generalized integration method applicable for various types of constitutive equations is developed and implemented into ABAQUS by means of UMAT subroutine. The solution of the non-linear system of algebraic equations arising from time discretization with the generalized midpoint rule is determined using line-search technique in combination with Newton method. The strategy to control the time increment for the improvement of the accuracy of the numerical integration is proposed. Several numerical examples are considered to demonstrate the efficiency and applicability of the present method. The prediction of the inelastic behavior of the structure is an essential part of reliability assessment procedure, because most of the failures are induced by the inelastic deformation, such as creep and plastic deformation. During decades, there has been much progress in understanding of the inelastic behavior of the materials and a lot of inelastic constitutive equations have been developed. These equations consist of the definition of inelastic strain and the evolution of the state variables introduced to quantify the irreversible processes occurred in the material. With respect to the definition of the inelastic strain, the inelastic constitutive models can be categorized into elastoplastic model, unified viscoplastic model and separated viscoplastic model and the different integration methods have been applied to each category. In the present investigation, the generalized integration method applicable for various types of constitutive equations is developed and implemented into ABAQUS by means of UMAT subroutine. The solution of the non-linear system of algebraic equations arising from time discretization with the generalized midpoint rule is determined using line-search technique in combination with Newton method. The strategy to control the time increment for the improvement of the accuracy of the numerical integration is proposed. Several numerical examples are considered to demonstrate the efficiency and applicability of the present method.

CMMI 기반 프로세스 지원 시스템 설계 (Design of Process Support System based on CMMI)

  • 최동희
    • 한국군사과학기술학회지
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    • 제12권3호
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    • pp.344-353
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    • 2009
  • In this paper, I have proposed a design of process support system based on CMMI process which can support integrated management and repository for CMMI model processes. The system assists small organization to improve business process and offers institutionalized automatic environment to users for use of CMMI processes. The proposed system also can enhance quality and productivity of project by including features such as convenience of project management, planned project administration and steady process improvement.

Integration of Strategic Issue Management and Knowledge Management in View of Strategic Information Paradigm - An Integrative Framework

  • Yum, Ji-Hwan;Mallikarjun, M.
    • 한국전자거래학회:학술대회논문집
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    • 한국전자거래학회 2005년도 e-Biz World Conference 2005
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    • pp.24-50
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    • 2005
  • Knowledge management is a current management concept dealing with information gathering and implementation processes for the organizational performance advantage. The study investigates knowledge management in two perspectives: internally, Organizational information processing structure and externally, strategic issue management system. The study proposes the existence of filtering processes in the organizations. Based on this argument, the authors propose that organizations need to employ strategic issue management system for the successful implementation of knowledge management.

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유한요소법을 이용한 자동차 패널의 성형 해석 (Simulation of Stamping of an Automotive Panel using a Finite Element Method)

  • 이종길;오수익
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1997년도 추계학술대회논문집
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    • pp.76-79
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    • 1997
  • In this study, an elasto-plastic finite element code, ESFORM, was developed to analyze sheet stamping processes. A formulation of 4-node degenerated shell element was implemented in the code. Workpiece materials were assumed to have planar anisotropy, and governed by associated flow rule. Explicit time integration method was employed to save computation time and reduce the required computer memory. Penalty method was used to describe interface behavior between workpiece and rigid die. Deep drawing of square cup and front finder stamping processes were simulated by ESFORM>

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초등 과학 우수 학생의 일상적 맥락의 과학 문제 해결 과정: 서답형 문항에 대한 응답 분석 (Everyday science problem solving processes of high ability elementary students in science: Analysis of written responses)

  • 김찬종
    • 한국초등과학교육학회지:초등과학교육
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    • 제17권1호
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    • pp.75-87
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    • 1998
  • The problem solving processes of elementary school children who are talented in science have been seldom studied. Researchers often resort to thinking aloud method to collect data of problem solving processes. The major purpose of the study is investigating high ability elementary school students' problem solving processes through the analysis of written responses to science problems in everyday context. 67 elementary students were participated Chungcheongbuk-do Elementary Science Contest held on October, 1997. The written responses of the contest participants to science problems in everyday context were analyzed in terms of problem solving processes. The findings of the research are as follows. (1) High ability elementary students use various concepts about air and water in the process of problem solving. (2) High ability elementary students use content specific problem solving strategies. (3) The problem solving processes of the high ability elementary students consist of problem representation, problem solution, and answer stages. Problem representation stage is further divided into translation and integration phases. Problem solving stage is composed of deciding relevant knowledge, strategy, and info..ins phases. (4) High ability elementary students' problem solving processes could be categorized into 11 qualitatively different groups. (5) Students failures in problem solving are explained by many phases of problem solving processes. Deciding relevant knowledge and inferring phases play major roles in problem solving. (6) The analysis of students' written responses, although has some limitations, could provide plenty of information about high ability elementary students' problem solving precesses.

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FeRAM 소자 제작 중에 발생하는 Pt/Al 반응 기구 (Pt/Al Reaction Mechanism in the FeRAM Device Integration)

  • 조경원;홍태환;권순용;최시경
    • 한국재료학회지
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    • 제14권10호
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    • pp.688-695
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    • 2004
  • The capacitor contact barrier(CCB) layers have been introduced in the FeRAM integration to prevent the Pt/Al reaction during the back-end processes. Therefore, the interdiffusion and intermetallic formation in $Pt(1500{\AA})/Al(3000{\AA})$ film stacks were investigated over the annealing temperature range of $100\sim500^{\circ}C$. The interdiffusion in Pt/Al interface started at $300^{\circ}C$ and the stack was completlely intermixed after annealing over $400^{\circ}C$ in nitrogen ambient for 1 hour. Both XRD and SBM analyses revealed that the Pt/Al interdiffusion formed a single phase of $RtAl_2$ intermetallic compound. On the other hand, in the presence of TiN($1000{\AA}$) barrier layer at the Pt/Al interface, the intermetallic formation was completely suppressed even after the annealing at $500^{\circ}C$. These were in good agreement with the predicted effect of the TiN diffusion barrier layer. But the conventional TiN CCB layer could not perfectly block the Pt/Al reaction during the back-end processes of the FeRAM integration with the maximum annealing temperature of $420^{\circ}C$. The difference in the TiN barrier properties could be explained by the voids generated on the Pt electrode surface during the integration. The voids were acted as the starting point of the Pt/Al reaction in real FeRAM structure.

LNG-FPSO 전처리 공정 에너지 시스템 분석 (Energy System Analysis of LNG-FPSO Pre-Ttreatment Processes by Heat Integration Technique)

  • 조하빈;김진국;민광준;임동하
    • 플랜트 저널
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    • 제8권4호
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    • pp.40-44
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    • 2012
  • 천연가스를 사용하기 위한 전처리공정에서 제거되는 물질인 산성 가스는 주로 아민계열 흡수제를 이용한 흡수공정을 통해 제거된다. 흡수공정 중 흡수탑에서 일어나는 흡수제의 산성가스 흡수반응은 발열반응이기 때문에 상대적으로 낮은 온도가 요구되며 역 반응이 일어나는 재생탑은 흡열반응을 위한 높은 온도 환경이 요구된다. 이는 두 탑의 흐름들 간에 열교환의 가능성이 있음을 의미한다. 본 연구에서는 DEA 흡수제를 이용한 흡수공정을 다양한 조건에서 사례연구를 시행하여 에너지 시스템을 분석하였으며, 흡수탑과 재생탑의 측면유출이 흡수공정의 전체 효율을 향상시킬 수 있음을 확인하였다.

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통합 제연시스템의 컨트롤러 개발에 관한 연구 (A Study on the Controller of Integration Smoke Control System)

  • 이동명
    • 한국화재소방학회논문지
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    • 제20권1호
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    • pp.77-82
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    • 2006
  • 본 연구에서는 온도가 보상된 압력을 제연구역의 기준압력으로 설정하기 위한 공학적인 메커니즘과 보상방법을 정립하였고, 통합 제연시스템의 컨트롤러의 개발을 위한 프로세스, 알고리즘 확립과 엔지니어링 데이터의 구축으로 신뢰성이 확보된 통합 제연시스템의 컨트롤러를 개발하였다. 컨트롤러를 개발함으로서 비제연구역의 압력측정을 위해서 별도로 설치되는 압력측정관을 생략할 수 있어 제작단가와 설치비용 및 작업공수를 줄일 수 있고, 층별 제연구역의 차압측정을 위한 비제연구역의 압력측정포트를 시스템에 일체화함으로서 차압의 정밀도를 향상시킬 수 있다. 기존의 개별제어 방식에서 통합 제연시스템의 컨트롤러로부터 중앙집중식 통합관리를 함으로서 보다 정확하고 신뢰성 있는 차압을 얻을 수 있으며, 제연시스템에 유연성을 부과시킬 수 있을 것으로 본다. 또한 통합 제연시스템의 기틀을 마련하고 제연의 유연성을 주며 방재성능을 향상시킬 것으로 본다.

An Exploratory Research on Entrepreneurial Ecosystems: Effects on Economic Integration

  • JUMASSEITOVA, Assel K.;POTLURI, Rajasekhara Mouly
    • The Journal of Asian Finance, Economics and Business
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    • 제7권8호
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    • pp.661-670
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    • 2020
  • This paper investigates the influence of the economic integration exemplified by the Eurasian Economic Union on the entrepreneurial ecosystem in the Kazakhstan corporate sector. Using data collected from 204 small-, medium-, and large-sized Kazakh companies, the researchers analyzed the collected data with percentile. Findings of this study show that small- and medium-sized enterprises, especially in the tertiary sector of the Kazakh economy, are not that much affected by regional integration, whereas large firms have been significantly impacted. The originality of the paper is threefold. First, the research explores the entrepreneurial ecosystems in its focus on geographic location or digital technologies that came across mainly from the ICT space. This is becoming pervasive across mechanical systems, communications, infrastructure, and the built-up environment. Second, the originality of the paper lies in focusing on the entrepreneurial ecosystems' influence on the business processes by clearly understanding the regional, national, and international trends in different markets. Third, the paper is first of its kind to contribute an updated perspective on the entrepreneurial ecosystem's influence on economic integration to the policymakers of Kazakhstan. Policymakers will gain expertise on how to manage network effects while planning investment projects, as well as transactions, modes, and fixed nodes, acquisition, and greenfield investments.

데이터사전을 이용한 ERP애플리케이션 개발 (ERP Application Development Using Business Data Dictionary)

  • Minsu Jang;Joo-Chan Sohn;Jong-Myoung Baik
    • 한국전자거래학회지
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    • 제7권1호
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    • pp.141-152
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    • 2002
  • Data dictionary is a collection of meta-data, which describes data produced and consumed while performing business processes. Data dictionary is an essential element for business process standardization and automation, and has a fundamental role in ERP application management and customization. Also, data dictionary facilitates B2B processes by enabling painless integration of business processes between various enterprises. We implemented data dictionary support in SEA+, a component- based scalable ERP system developed in ETRI, and found out that it's a plausible feature of business information system. We discovered that data dictionary promotes semantic, not syntactic, data management, which can make it possible to leverage viability of the tool in the coming age of more meta-data oriented computing world. We envision that business data dictionary is a firm foundation of adapting business knowledge, applications and processes into the semantic web based enterprise infra-structure.

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