• Title/Summary/Keyword: selection theory

Search Result 677, Processing Time 0.023 seconds

Adaptive Learning Control of Neural Network Using Real-Time Evolutionary Algorithm (실시간 진화 알고리듬을 통한 신경망의 적응 학습제어)

  • Chang, Sung-Ouk;Lee, Jin-Kul
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.26 no.6
    • /
    • pp.1092-1098
    • /
    • 2002
  • This paper discusses the composition of the theory of reinforcement teaming, which is applied in real-time teaming, and evolutionary strategy, which proves its the superiority in the finding of the optimal solution at the off-line teaming method. The individuals are reduced in order to team the evolutionary strategy in real-time, and new method that guarantee the convergence of evolutionary mutations are proposed. It is possible to control the control object varied as time changes. As the state value of the control object is generated, applied evolutionary strategy each sampling time because of the teaming process of an estimation, selection, mutation in real-time. These algorithms can be applied, the people who do not have knowledge about the technical tuning of dynamic systems could design the controller or problems in which the characteristics of the system dynamics are slightly varied as time changes. In the future, studies are needed on the proof of the theory through experiments and the characteristic considerations of the robustness against the outside disturbances.

Development of an Effective Strategy to Teach Evolution

  • Ha, Min-Su;Cha, Hee-Young
    • Journal of The Korean Association For Science Education
    • /
    • v.31 no.3
    • /
    • pp.440-454
    • /
    • 2011
  • This study proposes a new instructional strategy and corresponding materials designed from various alternative frameworks to help students understand evolution as a biologically acceptable theory. Biology teachers have normally taught the evolutionary mechanism by means of comparing Lamarckism with natural selection. In this study, a new instructional strategy in which the Lamarckian explanation is first excluded because Lamarckism is known to be subsumed in a learner's cognitive structure as a strong preconception of evolution is suggested for teaching evolution. After mutation theory is introduced, Darwinism including natural selection is explained separately during the next class hour. Corresponding instructional materials that aid student understanding of the evolutionary mechanism were developed using recently published articles on human genetic traits as scientific evolutionary evidence instead of the traditional evolutionary subject matter, giraffe neck. Evolutionary evidence from human genetic traits allows students to exclude anthropocentric thoughts effectively and raise concern for the phenomenon of evolution positively. The administered instructional strategy and materials in this research improved student conception, concern, and belief of evolution and it is believed that they helped students understand the evolutionary mechanism effectively.

Uncertainty Study: Information Seeking Behaviors of Doctoral Students in Business Management (정보행태 불확신성에 관한 연구 - 경영학분야 박사과정 연구자들을 중심으로 -)

  • Kim, Yang-Woo
    • Journal of the Korean BIBLIA Society for library and Information Science
    • /
    • v.23 no.1
    • /
    • pp.65-89
    • /
    • 2012
  • Using grounded theory, this study investigated users' information seeking behaviors associated with their perceptions of uncertainty. Based on a theoretical sampling, 17 doctoral students in the field of business management were recruited. Data was collected through the methods of questionnaire, interviewing, and think-aloud descriptions. The results identified user perceptions of uncertainty in the following stages: identification of information needs, selection of information systems, selection of search terms, actual use of systems, and evaluation of search results. In addition, positive aspects of uncertainties were presented. Major implications relate to information system and service improvements.

A Structure of Personalized e-Learning System Using On/Off-line Mixed Estimations Based on Multiple-Choice Items

  • Oh, Yong-Sun
    • International Journal of Contents
    • /
    • v.5 no.1
    • /
    • pp.51-55
    • /
    • 2009
  • In this paper, we present a structure of personalized e-Learning system to study for a test formalized by uniform multiple-choice using on/off line mixed estimations as is the case of Driver :s License Test in Korea. Using the system a candidate can study toward the license through the Internet (and/or mobile instruments) within the personalized concept based on IRT(item response theory). The system accurately estimates user's ability parameter and dynamically offers optimal evaluation problems and learning contents according to the estimated ability so that the user can take possession of the license in shorter time. In order to establish the personalized e-Learning concepts, we build up 3 databases and 2 agents in this system. Content DB maintains learning contents for studying toward the license as the shape of objects separated by concept-unit. Item-bank DB manages items with their parameters such as difficulties, discriminations, and guessing factors, which are firmly related to the learning contents in Content DB through the concept of object parameters. User profile DB maintains users' status information, item responses, and ability parameters. With these DB formations, Interface agent processes user ID, password, status information, and various queries generated by learners. In addition, it hooks up user's item response with Selection & Feedback agent. On the other hand, Selection & Feedback agent offers problems and content objects according to the corresponding user's ability parameter, and re-estimates the ability parameter to activate dynamic personalized learning situation and so forth.

A Flexible Network Access Scheme for M2M Communications in Heterogeneous Wireless Networks

  • Tian, Hui;Xie, Wei;Xu, Youyun;Xu, Kui;Han, Peng
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.9 no.10
    • /
    • pp.3789-3809
    • /
    • 2015
  • In this paper, we deal with the problem of M2M gateways' network selection for different types of M2M traffic in heterogeneous wireless networks. Based on the difference in traffic's quality of service (QoS) requirements, the M2M traffic produced by various applications is mainly classified as two categories: flexible traffic and rigid traffic. Then, game theory is adopted to solve the problem of network-channel selection with the coexistence of flexible and rigid traffic, named as flexible network access (FNA). We prove the formulated discrete game is a potential game. The existence and feasibility of the Nash equilibrium (NE) of the proposed game are also analyzed. Then, an iterative algorithm based on optimal reaction criterion and a distributed algorithm with limited feedback based on learning automata are presented to obtain the NE of the proposed game. In simulations, the proposed iterative algorithm can achieve a near optimal sum utility of whole network with low complexity compared to the exhaustive search. In addition, the simulation results show that our proposed algorithms outperform existing methods in terms of sum utility and load balance.

Causal and Intervening Conditions of Korean Immigrants' Sport Participation in the United States

  • KIM, Nam-Su;KIM, Min Soo;SEO, Won Jae
    • Journal of Sport and Applied Science
    • /
    • v.6 no.2
    • /
    • pp.19-25
    • /
    • 2022
  • Purpose: This study attempts to investigate causal and intervening conditions for sport participation of Korean immigrants in the United States. Research design, data, and methodology: Grounded theory approach was used to develop a conceptual framework that presents the psychosocial processes that occur in immigrants' experience of sport participation. Participants were selected purposefully for information-rich cases. Korean immigrants with current experience of having periodically participated in sports were the criterion for sample selection. Based on selection criteria, 9 Korean immigrants took part in interview. The interview discussions were taped and transcribed verbatim into a Word file. The process for data analysis included four grounded theory approaches of purposive and theoretical sampling, an open and axial coding, memo writing, and finally the development of the conceptual framework. Results: Six concepts were revealed in the causal conditions that facilitate the process of immigrants' sport participation in the states: Personal experience, significant others, personality, physical environment, psychological well-being, and social connection. Three concepts were revealed as the intervening conditions that block the process of immigrants' sport participation in the states: Conflict with cultural change of organization, Pressure at workplace, and Economic constraints. Conclusions: Conceptual model presents causal and intervening factors. Further implications were discussed.

Integration rough set theory and case-base reasoning for the corporate credit evaluation (러프집합이론과 사례기반추론을 결합한 기업신용평가 모형)

  • Roh, Tae-Hyup;Yoo Myung-Hwan;Han In-Goo
    • The Journal of Information Systems
    • /
    • v.14 no.1
    • /
    • pp.41-65
    • /
    • 2005
  • The credit ration is a significant area of financial management which is of major interest to practitioners, financial and credit analysts. The components of credit rating are identified decision models are developed to assess credit rating an the corresponding creditworthiness of firms an accurately ad possble. Although many early studies demonstrate a priori which of these techniques will be most effective to solve a specific classification problem. Recently, a number of studies have demonstrate that a hybrid model integration artificial intelligence approaches with other feature selection algorthms can be alternative methodologies for business classification problems. In this article, we propose a hybrid approach using rough set theory as an alternative methodology to select appropriate attributes for case-based reasoning. This model uses rough specific interest lies in lthe stable combining of both rough set theory to extract knowledge that can guide dffective retrevals of useful cases. Our specific interest lies in the stable combining of both rough set theory and case-based reasoning in the problem of corporate credit rating. In addition, we summarize backgrounds of applying integrated model in the field of corporate credit rating with a brief description of various credit rating methodologies.

  • PDF

Comparing Human Resources Theories of Technological Entrepreneurs : Asian Immigrants in the U.S. (기술기업가의 인적자원가설비교 : 미국의 아시안사례)

  • Lee, Sae-Jae
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.34 no.4
    • /
    • pp.106-113
    • /
    • 2011
  • Human resource theories of becoming entrepreneurs or self-employed rather than finding employment are compared as applied to fit the occupational data of technological entrepreneurs and technology jobs. The human capital theory posits that technological entrepreneurs are prepared to become a jack-of-all-trades with a variety of fields of education. Hobo theory of entrepreneurship assumes that entrepreneurs have strong taste against concentrating on a few activities, which tend to drive entrepreneurs away from employed jobs depressing their expected income. Another theory assumes that entrepreneurs have some unobserved productive qualities and abilities over employed people. Immigrant entrepreneurs could presumably be pressured out of employment under racial discrimination. Since technology jobs are mostly filled by those educated in the science and technology fields, and they presumably offer great reward to professional concentration, technological entrepreneurs may not benefit from becoming jacks-of-all-trades compared to finding employment in technological jobs income-wise. Asian immigrants in the 2000 US Census data are compared to white immigrants in technological jobs to test alternative human resource theories of entrepreneurship. Using English language ability as a proxy for the variety of education, I find in the white immigrant technological entrepreneurs support for the jack-of-all-trades theory, while in the Asian immigrant technological entrepreneurs hobo theory is supported. In the Asian technological workers only there appears the significant self-selection or comparative advantage component, while at the same time discriminatory components are significant.

A Study on the Analysis of Stress Distribution by Orthogonal Cutting Chip Model (2차원 절삭 칩 모델에 의한 응력분포 해석에 관한 연구)

  • 김정두;이은상;현동훈
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.17 no.12
    • /
    • pp.2926-2935
    • /
    • 1993
  • Chip breaker selection analysis, only being possible through experimental process, was obtained by a applied equation which used an orthogonal cutting model and a basic chip deformation. This equation could present an analysis of the chip breaking phenomena without the use of an actual experimetal method, and it was applied to computer simulation and proved the validity of theory through actual experiments. From these results, an efficient method for finding the optimum conditions of chip breaking was found through an optimized theory being applied to basic program. A finite element model for simulating chip breaking in orthogonal cutting was developed and discussed. By simulation the animation of chip breaking is observed in process on the computer screen.

From So Simple a Beginning, From So Simple a Theory

  • Choe, Jae-Chun
    • Journal of Ecology and Environment
    • /
    • v.32 no.4
    • /
    • pp.217-220
    • /
    • 2009
  • The year of 2009 marks the $200^{th}$ anniversary of Charles Darwin's birth and the 150th anniversary of the publication of his book, On the Origin of Species. Having survived the 150 years of hardening and tempering, Darwin's theory of natural selection is now more comprehensive and powerful than ever. It casts its shadow over nearly all academic disciplines and societal sectors. It truly revolutionized the way we look at the world and ourselves. In the midst of Darwinian revolution, however, Korea remains as a backward country as far as the understanding of Darwin and his theory is concerned. A variety of intellectual activities organized to celebrate the Year of Darwin is helping to narrow the gap. This article summarizes the kinds of such activities held in Korea this year and explains how Darwin made all this possible. To paraphrase the famous quotation by Theodosius Dobzhansky, I now dare to say, "Nothing in life makes sense except in the light of evolution".