• Title/Summary/Keyword: Open Systems

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A Comparative Study on Science Teacher Education System

  • Im, Sung-Min;Yoo, June-Hee;Pak, Sung-Jae
    • Journal of The Korean Association For Science Education
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    • v.21 no.5
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    • pp.855-866
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    • 2001
  • An important issue for qualified science teacher education should be a proper system of pre-service education for the science teacher. There are various types of science teacher education systems in accordance with their socio-cultural backgrounds. In this paper, science teacher education systems were analysed into 3 different types: Focusing Undergraduate Certification of Education (FUCE), Open Undergraduate Certification of Education (OUCE), and Post Graduate Certification of Education (PGCE). Science teacher education systems and their outcomes, such as the quality of the science teacher, were discussed with their socio-cultural backgrounds, compared by the 3 types of science teacher education systems. For this the results of meta-analysis from TIMSS-R and OECD data sets were used. Special interests focused on countries; Japan, Korea, the United Kingdom and the United States, which would represent stereotypes of science teacher education systems and different backgrounds of oriental and western culture.

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A Study on Singularly Perturbed Open-Loop Systems by Delta Operator Approach

  • Shim, Kyu-Hong;M. Edwin Sawan
    • Transactions on Control, Automation and Systems Engineering
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    • v.3 no.4
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    • pp.242-249
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    • 2001
  • In this paper, the open-loop state response of the two-time-scale systems by unified approach using the $\delta$-operator is presented with an example of the aircraft longitudinal dynamics. First, the $\delta$-operator system unifies both the continuous system and the discrete system simultaneously, and the $\delta$-operator approach improves the finite word-length characteristics. This saves more computing time than that of the discrete system. Second, the singular perturbation method by block diagonalization reduces the sizes and orders of the systems. This also reduces the floating-point operations (flops). The advantage of those two approaches is shown by comparing our results with the earlier ones in the illustrative example of the longitudinal motion of F-8 aircraft.

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What Makes Open Innovation Processes Better? A Focus on IT Professionals' Attitudes

  • Ham, Juyeon;Kim, Dan J.;Choi, Byounggu;Lee, Jae-Nam
    • Asia pacific journal of information systems
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    • v.25 no.2
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    • pp.306-328
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    • 2015
  • A recent trend in innovation paradigm is the shift from closed innovation to open innovation principles. This trend is characterized by the use of purposive inflows and outflows of knowledge not only to accelerate internal innovation, but also to expand the markets for external use of innovation. However, the Not-Invented-Here (NIH), and Not-Sold-Here (NSH) or Only-Use-Here (OUH) syndromes are the most common challenges encountered in open innovation processes. Therefore, this study has the following main aims: 1) propose a research model that explains the factors that influence NIH and NSH/OUH attitudes based on motivation theory with perceived organizational fairness and commitment, 2) investigate their impacts on NIH and NSH/OUH attitudes, and 3) provide useful theoretical and practical insights. The proposed research model was empirically tested using survey data collected from information technology (IT) professionals in Korea. One of the major findings indicates that IT professionals' perceived organizational fairness has a negative effect on NIH attitudes in open innovation process. Theoretical and practical contributions of this study are also discussed.

Design of Auto-growing FOAF Framework Using Social Network Service and OpenID (사회연결망 서비스와 OpenID를 이용한 자동 성장형 FOAF 프레임워크의 설계)

  • Lee, Dong-Hun;Lee, Seung-Hun;Kim, Geon-Su;Yun, Tae-Bok;Lee, Ji-Hyeong
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2008.04a
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    • pp.190-193
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    • 2008
  • 사용자의 '참여'를 지향하는 웹2.0 서비스들은 사람간이나 정보간의 '관계'에 대한 문제에 주목하고 있다. 대표적인 서비스인 블로그는 엮인글을 통해 사용자들의 참여를 이끌고 문서를 연결하고 있으나 이를 악용하는 사례들이 발생하고 있어 이에 대한 해결을 위해 연결에 대한 분석이 요구되고 있다. 사람의 개인 정보와 친구 관계 및 주변 사물과의 관계를 모델링하는 방식인 FOAF(Friend of a Friend)는 이러한 사회연결망 분석을 가능케 하는 수단으로써 연구되고 있다. FOAF는 단순화되고 이해하기 쉬운 용어를 사용하여, 복잡하고 이해하기 어려운 시맨틱 웹의 단점을 극복하기 위한 발판으로서 또한 주목 받고 있다. 본 연구에서는 여러 웹 사이트를 하나의 ID로 이용하기 위한 OpenID를 통해 FOAF에 정보 관리 능력을 부여하여 개인정보 유출 문제를 해결하기 위한 방안을 제시한다. 또한 실제 운영되는 관리 능력을 부여하여 개인정보 유출 문제를 해결하기 위한 방안을 제시한다. 또한 실제 운영되는 사회연결망 서비스의 분석을 통해 OpenID의 정보에 따라 자동으로 사회연결망 정보를 수집하는 성장형 FOAF 프레임워크를 설계하였으며, 쉬운 FOAF를 보급하기 위한 발판을 마련하였다.

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Analysis of the Initial Cost Payback Period on the Open-loop Geothermal System Using Two Wells (복수정을 이용한 개방형 지열 시스템의 초기투자비 회수기간 분석)

  • Cho, Jeong-Heum;Nam, Yujin
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.29 no.3
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    • pp.119-126
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    • 2017
  • Recently, ground source heat pump systems are being used in buildings for cooling and heating to reduce greenhouse gas and save energy. However, ground source heat pump systems mainly use the vertical closed-loop geothermal system design rather than the open-loop geothermal system design. This is due to a lack of knowledge and few research feasibility studies. In this research, a dynamic thermal analysis numerical simulation based on a standard house model was conducted for an open-loop geothermal system. Based on heating load analysis results, the life cycle costs of a standard house using an open two-well geothermal system were analyzed and compared with a vertical closed-loop geothermal system, and a diesel boiler. As a result, it was found that using an open two-well geothermal system shows economic return on investment after three years.

Open Architecture of Transportation Information Dissemination using OPEN API (OPEN API를 이용한 개방형 교통정보 제공기법)

  • Lee, Ji-Won;Nam, Doo-Hee
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.1
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    • pp.109-114
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    • 2012
  • Intelligent Transportation Systems (ITS) is aimed to implement IT(Information Technology) to develop the next-generation transportation system in order to improve traffic conditions. In order to provide traffic information, the methods that provide available traffic informations to the public are needed. In this paper, analysis of the transportation applications in smart-phone and currently available methods of traffic information's sharing and providing were discussed. Finally, OPEN API was discussed and shows its effectiveness for transportation information area especially in smart phone.

Electrically-induced actuation for open-loop control to cancel self-excitation vibration

  • Makihara, Kanjuro;Ecker, Horst
    • Smart Structures and Systems
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    • v.9 no.2
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    • pp.189-206
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    • 2012
  • This paper focuses on the actuation system combined with a piezoelectric transducer and an electric circuit, which leads to a new insight; the electric actuation system is equivalent to mechanical variable-stiffness actuation systems. By controlling the switch in the circuit, the electric status of the piezoelectric transducer is changed, and consequently a variable-stiffness mechanism is achieved on the electric actuator. This proposed actuator features a shift in the equilibrium point of force, while conventional electrically-induced variable-stiffness actuators feature the variation of the stiffness value. We intensively focus on the equilibrium shift in the actuation system, which has been neglected. The stiffness of the variable-stiffness actuator is periodically modulated by controlling the switch, to suppress the vibration of the system in an open-loop way. It is proved that this electric actuator is equivalent to its mechanical counterpart, and that the electrical version has some practical advantages over the mechanical one. Furthermore, another kind of electrically-induced variable-stiffness actuator, using an energy-recycling mechanism is also discussed from the viewpoint of open-loop vibration control. Extensive numerical simulations provide comprehensive assessment on both electrically-induced variable-stiffness actuators employed for open-loop vibration control.

Empirical Study of the Relationship between Communication-Structure Characteristics and Open Collaboration Performance: Focusing on Open-Source Software Development Platform (개방형 협업 커뮤니케이션 특성과 협업 성과 : 오픈소스 소프트웨어 개발을 중심으로)

  • Lee, Saerom;Jang, Moonkyoung;Baek, Hyunmi
    • The Journal of Information Systems
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    • v.28 no.1
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    • pp.73-96
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    • 2019
  • Purpose The purpose of this study is to examine the effect of communication-structure characteristics on performance in online collaboration using the data from Github, one of representative open source software development platforms. We analyze the impact of in-degree/out-degree centralization and reciprocity of communication network on collaboration performance in each project. In addition, we investigate the moderating effect of owner types, an individual developer or an organization. Design/methodology/approach We collect the data of 838 Github projects, and conduct social network analysis for measuring in-degree/out-degree centralization and reciprocity as independent variables. With these variables, hierarchical regression analysis is employed on the relationship between the characteristics of communication structure and collaborative performance. Findings Our results show that for the project owned by an organization, the centralized structure of communication is not associated with the collaboration performance. In addition, the reciprocity is positively related to the collaboration performance. On the other hand, for the project owned by an individual developer, the centralized structure of communication is positively related to the performance, and the reciprocity does not show the positive relationship on the performance.

The Role of Firm Size and IT Capabilities in Open and Closed Innovation

  • Byounggu Choi
    • Asia pacific journal of information systems
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    • v.29 no.4
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    • pp.690-716
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    • 2019
  • Open innovation has attracted significant attention from both academics and practitioners. However, theoretical and empirical researchers disagree on how open innovation improves firm performance. The inconsistent results reported in the literature may be attributed to the fact that they failed to provide an integrative view of how to make use of internal and external knowledge to enhance innovation performance. Furthermore, although the adoption value of innovation approaches varies depending on firm size and IT capabilities, their impacts have not been adequately taken into consideration. Drawing on complementarity theory, this study revisits the research problem and develops eight hypotheses. Surveys collected from 339 Korean firms were analyzed to test the hypotheses using the supermodularity functions. The results indicated that an internal knowledge-oriented innovation approach has a positive impact on innovation performance regardless of firm size. However, an external knowledge-oriented innovation approach has a positive effect on innovation performance in large firms while having no significant effect on innovation performance of SMEs. Results also confirmed a complementary relationship between internal and external knowledge-oriented innovation approaches in large firms, whereas substitutable relationships were confirmed in SMEs. This study sheds new light on open innovation by identifying the role of different types of innovation approaches, firm size, and IT capabilities.

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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