• Title/Summary/Keyword: World-systems

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Availability of Energy and Reconstruction of Thermodynamics(I) Thermodydamics of the Reversible World (에너지의 가용성과 열역학의 재구성 (I) 가역세계 열역학)

  • 정평석;노승탁
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.5
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    • pp.1227-1236
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    • 1993
  • In conventional thermodynamics, energy is regarded as a physical quantity transferring from one system to another, but in present study, the real energy is regarded as a physical quantity coming out from one interaction and absorbing into another interaction between two systems. To reconstruct thermodynamics with such a point of view, available work is distinguished from half work in conventional work concepts, and a special space named reversible world is proposed in which every process is reversible and the only measurable quantity is available work and just the equality between the intensities of two systems can be verified. As results, thermodynamic laws are arranged into two principles in the reversible world-conservations of energy elements and conservation of available energy. It means the exsistences of state properties corresponding to transferring energy elements and the available work. The former are extensive properties and the later is named potential work which is a property of the composite system and a kind of mathematical distance. The conventional available energy (exergy) and internal energy can be explained as the special cases of potential work, and the conventional first law of thermodynamics can be derived from the principle of the conservation of available energy. With these new concepts, the description of thermodynamic processes is more comprehensive. The second law of thermodynamics is no longer needed in the reversible world.

An Information Sharing System for Product Design Data Using WWW and STEP (웹과 STEP을 이용한 제품 설계 정보 공유 시스템)

  • 김철영;김남국;김영호;강석호
    • Korean Journal of Computational Design and Engineering
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    • v.1 no.3
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    • pp.203-214
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    • 1996
  • An information sharing system, namely World Design View, is developed for browsing product design data on the World Wide Web environment. For the last few years information sharing has been rapidly emerging as an important research issue in the areas of concurrent engineering, product data management, virtual manufacturing, and so on. Since we are mainly concerned with product development, the key information that needs be communicated and shared is product data. The developed system puts the major advantages of STEP, OODB, and VRML together. The STEP standard provides a consistent data exchange format and application interfaces among different CAD/CAM systems. OODB is efficient and effective in dealing with complex data structures often found in engineering applications. Virtual worlds for 3-D product models can be created by VRML which is networked via the global Internet and hyperlinked with WWW. The World Design View system can support for members of virtual design teams, possibly distributed all over the world, to share 3-D shape information quickly and easily.

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Modeling and Identification of Human Mind using a Robot Which Walks Together

  • Kwon, Oh-Kyu;Park, Poo-Gyeon
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.161.2-161
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    • 2001
  • To achieve a cooperative work between human and robot, it is thought helpful to estimate the states of human mind, which originates his behavior. In this paper, human mind was considered to modify instinctive desires according to the conditions of external world surrounding the instinct. A simple human mind model was designed so that it finds a balance between instinctive desire and restriction from the external world. The external world is divided into three sub-worlds like subject´s whole body, its partner and concerned periphery. Proposed mind model has three-layers construction. Each of the layer tries to find a balance between desire and restriction from external world. In each layer, the role of finding the balance was expressed by an identical optimal control minimizing a performance index function of quadratic form with a weight factor, which is rearranged and named ...

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The Social Security Pension Reform Debate between the World Bank and the ILO/ISSA (World Bank와 ILO/ISSA의 사회보장연금 민영화 논쟁에 관한 연구)

  • Won, Seok-Jo
    • Korean Journal of Social Welfare
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    • v.46
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    • pp.290-318
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    • 2001
  • In 1981, Chile has fundamentally reformed the public pension system from the pay-as-you-go system (PAYGs) to the full funding defined contribution system managed by the private funding companies. The Chilean privatization reform influenced not only the neighbor South American countries but also the advanced countries. The United Kingdom contracted out the state earning related pension system. Australia and Sweden recently introduced the private investment accounts system. And now the hot debates on the privatization of the social security pension is going on in the United States of America. This wind of privatizing the public pension system is being backed up by the New Liberalism, the nowadays' strongest ideology. Besides, the theoretical and idealogical debate between the World Bank and the ILO/ISSA was happened in the middle of 1990s. The World Bank, the supporter of the international financial capital, insisted the introducing of the full funding individual accounts system and the abolition of the existing PAYGs. The ILO/ISSA apposed the World Bank's policies and advocated the moderate reform of the PAYGs. In this paper, I reviewed the Chilean reform, the World Bank's report and the opposing argument of the ILO/ISSA against it, and analysed the core issues of the two sides. Also, I tried to present the suggestions to the Korean public pension systems. Through the discussing the debate, we made certain of the importance of the basic issues in the social security system like equity vs. adequacy, inter-generational redistribution vs. intra-generational redistribution and welfare vs. economy, once again.

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The Performance and Implication of A Market-oriented Health Care System in United States (미국 시장지향 의료체계의 성과와 시사점)

  • Lee, Key-Hyo
    • Korea Journal of Hospital Management
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    • v.9 no.1
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    • pp.1-21
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    • 2004
  • The United States has a unique health care system, which is unlikely any other health care systems in the world. The major part of basic functional components of the system -financing, insurance, delivery, and payment- is in private hands. A market-oriented economy invites the participation of numerous private entities that are interested in carrying out the key functions of health systems. Due to this central feature, U.S.health care is not delivered through a network of interrelated components designed to work together coherently. For lack of standardization, the various components of the system fit together only loosely. The involvement of numerous players in the key functions leads to duplication, overlap, inadequacy, inconsistency, and waste, which add to the complexity and also make the system inefficient. Hence, cost containment remains an elusive goals. Moreover, the system falls short of delivering equitable services to all americans, though consumption of health care services is the largest in the world. On the other hand, United States leads the world in the latest and the best in medical technology, medical training, and research. It offers some of the most sophisticated institutions, products, and processes of health care delivery. This article discuss the characteristic features of the U.S. health care system. and its performance, trying to seek its implication on Korean health care system.

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A New Effective SAP ERP Education Approach Through The Development of Educational Virtual Company (SAP ERP 시스템 교육을 위한 교육용 가상기업 구현 전략)

  • Kim, Yeong-Real
    • Journal of Korea Society of Industrial Information Systems
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    • v.16 no.1
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    • pp.49-58
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    • 2011
  • Among the various ERP solutions, SAP R/3 solution has been chosen because SAP system follows global standard processes which include most of business solutions for various industries. The ERP education is limited by learning theory only and they are not sufficient for understanding wide scale of business processes. Real world scenarios with hands on experience approach will be the core aspect of this article. As per real world scenarios, "ChungBuk Motors. Corp." has been created and students are asked to create the organization structure and the procurement process for this virtual enterprise. As a result, students attending this class showed better understanding of overall ERP system comparing to the students attended other ERP classes. The hands-on experience with real-world scenarios proved that it is most practical and efficient solution for educating ERP system.

Pick Up and Delivery Vehicle Routing Problem Under Time Window Using Single Hub (단일 허브를 이용한 시간 제약이 존재하는 수거 및 배달 차량 경로 문제)

  • Kim, Jiyong
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.42 no.4
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    • pp.16-22
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    • 2019
  • After Dantzig and Rasmer introduced Vehicle Routing Problem in 1959, this field has been studied with numerous approaches so far. Classical Vehicle Routing Problem can be described as a problem of multiple number of homogeneous vehicles sharing a same starting node and having their own routes to meet the needs of demand nodes. After satisfying all the needs, they go back to the starting node. In order to apply the real world problem, this problem had been developed with additional constraints and pick up & delivery model is one of them. To enhance the effectiveness of pick up & delivery, hub became a popular concept, which often helps reducing the overall cost and improving the quality of service. Lots of studies have suggested heuristic methods to realize this problem because it often becomes a NP-hard problem. However, because of this characteristic, there are not many studies solving this problem optimally. If the problem can be solved in polynomial time, optimal solution is the best option. Therefore, this study proposes a new mathematical model to solve this problem optimally, verified by a real world problem. The main improvements of this study compared to real world case are firstly, make drivers visit every nodes once except hub, secondly, make drivers visit every nodes at the right time, and thirdly, make drivers start and end their journey at their own homes.

Camera Calibration Using the Fuzzy Model (퍼지 모델을 이용한 카메라 보정에 관한 연구)

  • 박민기
    • Journal of the Korean Institute of Intelligent Systems
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    • v.11 no.5
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    • pp.413-418
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    • 2001
  • In this paper, we propose a new camera calibration method which is based on a fuzzy model instead of a physical camera model of the conventional method. The camera calibration is to determine the correlation between camera image coordinate and real world coordinate. The camera calibration method using a fuzzy model can not estimate camera physical parameters which can be obtained in the conventional methods. However, the proposed method is very simple and efficient because it can determine the correlation between camera image coordinate and real world coordinate without any restriction, which is the objective of camera calibration. With calibration points acquired out of experiments, 3-D real world coordinate and 2-D image coordinate are estimated using the fuzzy modeling method and the results of the experiments demonstrate the validity of the proposed method.

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Country Clustering Based on Environmental Factors Influencing on Software Piracy (소프트웨어 불법복제에 영향을 미치는 환경 요인에 기반한 국가 분류)

  • Suh, Bomil;Shim, Junho
    • The Journal of Information Systems
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    • v.26 no.4
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    • pp.227-246
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    • 2017
  • Purpose: As the importance of software has been emphasized recently, the size of the software market is continuously expanding. The development of the software market is being adversely affected by software piracy. In this study, we try to classify countries around the world based on the macro environmental factors, which influence software piracy. We also try to identify the differences in software piracy for each classified type. Design/methodology/approach: The data-driven approach is used in this study. From the BSA, the World Bank, and the OECD, we collect data from 1990 to 2015 for 127 environmental variables of 225 countries. Cronbach's ${\alpha}$ analysis, item-to-total correlation analysis, and exploratory factor analysis derive 15 constructs from the data. We apply two-step approach to cluster analysis. The number of clusters is determined to be 5 by hierarchical cluster analysis at the first step, and the countries are classified by the K-means clustering at the second step. We conduct ANOVA and MANOVA in order to verify the differences of the environmental factors and software piracy among derived clusters. Findings: The five clusters are identified as underdeveloped countries, developing countries, developed countries, world powers, and developing country with large market. There are statistically significant differences in the environmental factors among the clusters. In addition, there are statistically significant differences in software piracy rate, pirated value, and legal software sales among the clusters.

An Educational Service Platform using Collective Intelligence and Presence of Web 2.0

  • Kim, Chang-Suk;Son, Dong-Cheul;Cho, Chung-Ho
    • Journal of the Korean Institute of Intelligent Systems
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    • v.19 no.1
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    • pp.115-121
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    • 2009
  • Web 2.0 has become the face next generation Web among the business world and research community. Web 2.0 is instant superficial gratification of people. On the other hand, Semantic Web is deep, meaningful and lasting relationship with data. So, it is difficult to apply the Semantic Web to the real world. In this paper, a platform for educational services using the Semantic Web and Web 2.0 is proposed. The proposed platform is based mix of the Semantic Web and Web 2.0, so it is useful to apply in the real world applications. Two services are presented, one is a semantic email system and the other is a cyber study space. The cyber study space adjusted each student is presented. The study environment is called iStudySpace that has personal scheduler, study status plan table, personalized search engine and several gadgets. Finally characteristics and limitations of the Semantic Web and Web 2.0, the organization and components of the platform, evaluation of iStudySpace are shown.