• Title/Summary/Keyword: Evolution strategy

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Bayesian Neural Network with Recurrent Architecture for Time Series Prediction

  • Hong, Chan-Young;Park, Jung-Hun;Yoon, Tae-Sung;Park, Jin-Bae
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.631-634
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    • 2004
  • In this paper, the Bayesian recurrent neural network (BRNN) is proposed to predict time series data. Among the various traditional prediction methodologies, a neural network method is considered to be more effective in case of non-linear and non-stationary time series data. A neural network predictor requests proper learning strategy to adjust the network weights, and one need to prepare for non-linear and non-stationary evolution of network weights. The Bayesian neural network in this paper estimates not the single set of weights but the probability distributions of weights. In other words, we sets the weight vector as a state vector of state space method, and estimates its probability distributions in accordance with the Bayesian inference. This approach makes it possible to obtain more exact estimation of the weights. Moreover, in the aspect of network architecture, it is known that the recurrent feedback structure is superior to the feedforward structure for the problem of time series prediction. Therefore, the recurrent network with Bayesian inference, what we call BRNN, is expected to show higher performance than the normal neural network. To verify the performance of the proposed method, the time series data are numerically generated and a neural network predictor is applied on it. As a result, BRNN is proved to show better prediction result than common feedforward Bayesian neural network.

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The Status of Unilateral Arbitration Agreements Through the U.S. Case Laws (미국법원의 판례를 통한 선택적 중재합의의 지위)

  • Ha, Choong-Lyong;Park, Won-Hyung
    • Journal of Arbitration Studies
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    • v.17 no.1
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    • pp.77-95
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    • 2007
  • This article focuses on the history and evolution of the US court's attitude towards unilateral arbitration and dispute resolution clauses, but also considers the practical approach of national courts to theses clauses. It goes on to consider some potential pitfalls in the operation of unilateral clauses, which should be borne in mind when developing a strategy for bringing or defending a claim which falls within the scope of a unilateral clause. There can be few objections to the general validity of unilateral arbitration clauses. The principle of party autonomy is the driving force behind international arbitration and, provided it is tolerably clear that the parties intended the arbitration clause to operate unilaterally, courts should be reluctant to interfere with the parties' agreement. There are also no persuasive public policy reasons why such clauses should not be upheld in commercial agreements. In addition to the issue of whether such unilateral clauses are permissible under certain law, it is important to be aware of how they should properly operate in practice, that is, useful guidance on the subject of the proper operation and effect of such clauses where they are intended to be used to enable a party to decide whether, and in what circumstances, a claim should be referred to court or to arbitration.

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Effect of Number of Turns of Pancake Windings on Central Magnetic Field of the HTS Magnet (팬케이크 권선의 권선수가 고온초전도 마그넷의 중심자장에 미치는 영향)

  • Kang, Myung-Hun;Lee, Kwang-Youn;Lee, Yong-Seok;Cha, Guee-Soo;Lee, Hee-Joon
    • Proceedings of the KIEE Conference
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    • 2007.04c
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    • pp.107-109
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    • 2007
  • Pancake windings have merits that are easier to make high field magnets and replace windings when an accident happens and windings are aged. The current of the whole magnet consisted of windings connected in series was limited by the minimum current of the top and bottom pancake windings where maximum perpendicular magnetic field was applied. This paper propose a optimal design of a HTS magnet excited by a single source, where evolution strategy was adopted for optimal design algorithm. A magnet consisted of 8 BSCCO pancakes was chosen to prove the effectiveness of this optimal design method. Magnetic field at the center of a magnet was chosen as the object function and it was used maximized. Results of the optimal design shows that the increment of the number of turns of the pancake winding make the magnetic field of the center of the magnet increase but the current of the winding decrease for the larger perpendicular magnetic field.

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A study on the optimal sizing and topology design for Truss/Beam structures using a genetic algorithm (유전자 알고리듬을 이용한 트러스/보 구조물의 기하학적 치수 및 토폴로지 최적설계에 관한 연구)

  • 박종권;성활경
    • Journal of the Korean Society for Precision Engineering
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    • v.14 no.3
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    • pp.89-97
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    • 1997
  • A genetic algorithm (GA) is a stochastic direct search strategy that mimics the process of genetic evolution. The GA applied herein works on a population of structural designs at any one time, and uses a structured information exchange based on the principles of natural selection and wurvival of the fittest to recombine the most desirable features of the designs over a sequence of generations until the process converges to a "maximum fitness" design. Principles of genetics are adapted into a search procedure for structural optimization. The methods consist of three genetics operations mainly named selection, cross- over and mutation. In this study, a method of finding the optimum topology of truss/beam structure is pro- posed by using the GA. In order to use GA in the optimum topology problem, chromosomes to FEM elements are assigned, and a penalty function is used to include constraints into fitness function. The results show that the GA has the potential to be an effective tool for the optimal design of structures accounting for sizing, geometrical and topological variables.variables.

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The Rise of Korean Innovation Policy for Social Problem-Solving: A Policy Niche for Transition?

  • Seong, Jieun;Song, Wichin;Lim, Hongtak
    • STI Policy Review
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    • v.7 no.1
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    • pp.1-16
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    • 2016
  • Technology supply has been the main thrust of the Korean government's science & technology policy, focusing on the development and acquisition of new technology in line with the catching-up strategy of economic growth and industrial development. However, new social or societal problems have become major government policy issues, heralding new innovation policy aimed to address them. Such new policy initiatives for social problem-solving present a niche where the existing system of government innovation policy process is challenged, including such processes as goal-setting, planning, implementation, project management, and evaluation. The rigidity of the existing institution of government innovation policy, however, still shapes the content and progression of innovation policy for social problem-solving. This study reviews Korean innovation policy for social problem-solving as a policy niche, and aims to clarify its challenges and opportunities. It uses a system transition framework to explain the emergence and evolution of the innovation policy niche in Korea. The main research question is to what extent and in what aspect the existing innovation policy regime shaped innovation policy for social problem-solving. The study examines the inertia of the current paradigm of innovation policies and R&D programs, and sheds light on the search for a distinctive identity for innovation policies that tackles social problems.

A Study of Contemporary Fashion Industry According as the Change of Customer's Cultural Trend - Focusing on the 'Meme' Theory of Richard Dowkins - (소비자 문화 트렌드 변화에 따른 현대 패션산업 특성 고찰 - 리처드 도킨스의 밈(meme) 이론을 중심으로 -)

  • Yang, Hee-Young
    • Journal of the Korea Fashion and Costume Design Association
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    • v.15 no.4
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    • pp.83-99
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    • 2013
  • This research is a follow-up study about analysis on the many different customer groups and their various culture trend, which intends to realize diverse values depending on the sense. The purpose of this study was to develop direction forecast for the future fashion industry through consideration about the characteristics of contemporary fashion industry by the change of different customer's culture trend. And also try to find solution to survival strategy of fashion fields able to evolve with customer. Change of the customer's cultural trend draws a shift in policy in the 21st fashion industry as follows : 1) mash-up 2) complexation through decentering and blurring 3) invisible and immaterial value oriented 4) expansion of minor small market. Moreover, this shows sociocultural meaning as follows. First is spread of flexible and horizontal relationship through collaborative consumption and collaboration. Second is concentration on floating and indeterminate chance through dismantling of various different fashion categories. Third is formation of the permanent difference by selection and focus. Last is expansion of understanding about cultural-ecology. Customer cultural trend is 'meme' of cultural gene in fashion field, so it intends to co-evolute with customer by continuous change.

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A Case Study on the Team Conflict Phenomenon in IT Service Project (IT서비스 프로젝트에서의 팀 내 갈등현상에 관한 비교사례연구)

  • Park, Sang-Hee;Cho, Nam-Jae
    • Journal of Information Technology Applications and Management
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    • v.16 no.4
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    • pp.109-134
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    • 2009
  • Compared to research on the success of IT projects in general, research on the management of conflict in IT teams and its impact on project success is insufficient. This research performed a comparative study to analyze the nature and evolving phenomenon of conflicts in IT project teams. This study aimed at; First, Why a conflict is created within and around an IT project team. Second, What is the phenomenon of conflict evolution, diffusion, and/or resolution? Third, How the differences in conflict management style affects the IT project performance? Three propositions were drawn from the analysis of two intensive analysis of conflict cases and their comparison. Proposition 1 : Both 'the method of pointing out a problem' and 'the pointed-out contents' can be the trigger of conflicts around an IT project. Proposition 2 : While the focus of attention of one party is 'the method of pointing out a problem', if the other's and focus of attention of one party is 'the pointed-out contents', that is, if the focus of attention mismatch, the conflict can be amplified. Proposition 3 : According to the temporal nature of the relationship, e.g., short-term versus long-term, the way people approach and deal with the conflict differs.

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Institutional Determinants of Technical Innovation in ICT Industry : Based on An Empirical Analysis of OECD Countries (ICT 산업에서 기술 혁신에 영향을 미치는 제도적 요인 분석 연구 : OECD 국가의 실증분석을 중심으로)

  • Lee, Hyun Jung;Kim, Hee Sun;Kim, Jeong Ju
    • Journal of Information Technology Applications and Management
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    • v.23 no.4
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    • pp.1-23
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    • 2016
  • The growth of information and communication technology (ICT) has led to a rapid of business paradigm shift incurred in the creation of new social/market value, changes of a value chain and elements producing a value creation, and enlargement of the scope of market competition. It leads to the change and evolution of industrial structure, requiring innovations of policy and institution. However, most studies that have focused on the effect of policy and institution on innovation are based on thick description and qualitative evidence, while paying little attention to these linkages in an empirical way. Hence this study has attempted to empirically analyze policy and institutional factors affecting innovation performance, particularly attention to ICT industry in OECD countries. The findings derived from the empirical analysis provide important implications for catch-up countries in relation to the innovations of policy and institution for effective innovation system and start-up ecosystem.

Bit-to-Symbol Mapping Strategy for LDPC-Coded Turbo Equalizers Over High Order Modulations (LDPC 부호 기반의 터보 등화기에 적합한 고차 변조 심볼사상)

  • Lee, Myung-Kyu;Yang, Kyeong-Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.5C
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    • pp.432-438
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    • 2010
  • In this paper we study the effect of bit-to-symbol mappings on the convergence behavior of turbo equalizers employing low-density parity-check (LDPC) codes over high order modulations. We analyze the effective SNR of the outputs from linear minimum mean-squared error (MMSE) equalizers and the convergence property of LDPC decoding for different symbol mappings. Numerical results show that the bit-reliability (BR) mapping provides better performance than random mapping in LDPC-coded turbo equalizers over high order modulations. We also verify the effect of symbol mappings through the noise threshold and error performance.

SI 프로젝트팀 내 발생 갈등현상에 관한 비교사례연구

  • Park, Sang-Hui;Jo, Nam-Jae
    • Proceedings of the Korea Database Society Conference
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    • 2010.06a
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    • pp.109-123
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    • 2010
  • Compared to research on the success of IT projects In general, research on the management of conflict in IT teams and its impact on project success is insufficient. This research performed a comparative study to analyze the nature and evolving phenomenon of conflicts in IT project teams. This study aimed at; First, Why a conflict is created within and around an IT project team. Second, What is the phenomenon of conflict evolution, diffusion, and/or resolution? Third, How the differences in conflict management style affects the IT project performance? Three propositions were drawn from the analysis of two intensive analysis of conflict cases and their comparison. Proposition 1 : Both 'the method of pointing out a problem' and 'the pointed-out contents' can be the trigger of conflicts around an IT project. Proposition 2 : While the focus of attention of one party is 'the method of pointing out a problem', if the other's and focus of attention of one party is 'the pointed-out contents', that is, if the focus of attention mismatch, the conflict can be amplified. Proposition 3 : According to the temporal nature of the relationship, e.g., short-term versus long-term, the way people approach and deal with the conflict differs.

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