• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.165.2-165
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• 2001

A number of previous researches in evolutionary algorithm are based on the study of facets we observe in natural evolution. The individuals of species in natural evolution occupy their own niche that is a subdivision of the habitat. This means that two species with the similar requirements cannot live together in the same niche. This is known as the competitive exclusion principle, i.e., complete competitors cannot coexist. In this paper, a new evolutionary programming algorithm adopting this concept is presented. Similarly in the case of natural evolution , the algorithm Includes the concept of niche obtained by partitioning a search space and the competitive exclusion principle performed by migrating individuals. Cell partition and individual migration strategies are used to preserve search diversity as well as to speed up convergence of an ...

• 기술경영경제학회:학술대회논문집
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• 기술경영경제학회 1998년도 제13회 하계학술발표회 논문집
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• pp.57-90
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• 1998

This study attempts to explore the evolution paths of Korean SMEs'strategies and their technological teaming processes. Several different evolution paths are identified based on a dynamic strategic group analysis of 115 SMEs'strategy in the Korean electronic component industry for the period of 1990-1995. Further, inadept case analyses on technological learning processes in 5 firms are undertaken. Major findings of this study can be summarized as follows : 1) There are three dominant evolution paths in SMEs'strategy. First path indicates the evolution from a subcontractor or petty imitator group(a strategic group with the narrow product/market domain and the low level of accumulated resource/capabilities) into an innovator group(a strategic group with the narrow domain but high level of technological capability) by accumulating technological capabilities. Second, some firms move from a subcontractor group into a generalizer group(a strategic group with broad product/market domain but relatively low level of technological capability) by simply adding product lines. Third path involves firms which evolve from a subcontractor group into a production focus group(a strategic group with high level of production capability) by investing in production capabilities. 2) An in-depth case analysis shows those who succeeded in technological learning are managed by CEOs, who have technological expertise and strategic vision, and have made an effort to establish management practices to support innovation, such employee educational program, performance-based reward system, etc. The successful firms also aggressively pursue diverse external linkages with outside technology sources to learn product and process technologies. Fiendly, this study discusses several implications of the findings for the theoretical development and strategic management of small firms in Korea.

• Journal of Communications and Networks
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• 제16권5호
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• pp.523-533
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• 2014

Orthogonal frequency division multiple access (OFDMA) is a promising technique, which can provide high downlink capacity for the future wireless systems. The total capacity of OFDMA can be maximized by adaptively assigning subchannels to the user with the best gain for that subchannel, with power subsequently distributed by water-filling. In this paper, we propose the use of composite differential evolution (CoDE) algorithm to allocate the subchannels. The CoDE algorithm is population-based where a set of potential solutions evolves to approach a near-optimal solution for the problem under study. CoDE uses three trial vector generation strategies and three control parameter settings. It randomly combines them to generate trial vectors. In CoDE, three trial vectors are generated for each target vector unlike other differential evolution (DE) techniques where only a single trial vector is generated. Then the best one enters the next generation if it is better than its target vector. It is shown that the proposed method obtains higher sum capacities as compared to that obtained by previous works, with comparable computational complexity.

• Journal of Astronomy and Space Sciences
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• 제31권2호
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• pp.121-130
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• 2014

Essential ideas, successes, and difficulties of Areal Density Analysis (ADA) for color-magnitude diagrams (CMD's) of resolved stellar populations are examined, with explanation of various algorithms and strategies for optimal performance. A CMD-generation program computes theoretical datasets with simulated observational error and a solution program inverts the problem by the method of Differential Corrections (DC) so as to compute parameter values from observed magnitudes and colors, with standard error estimates and correlation coefficients. ADA promises not only impersonal results, but also significant saving of labor, especially where a given dataset is analyzed with several evolution models. Observational errors and multiple star systems, along with various single star characteristics and phenomena, are modeled directly via the Functional Statistics Algorithm (FSA). Unlike Monte Carlo, FSA is not dependent on a random number generator. Discussions include difficulties and overall requirements, such as need for fast evolutionary computation and realization of goals within machine memory limits. Degradation of results due to influence of pixelization on derivatives, Initial Mass Function (IMF) quantization, IMF steepness, low Areal Densities ($\mathcal{A}$), and large variation in $\mathcal{A}$ are reduced or eliminated through a variety of schemes that are explained sufficiently for general application. The Levenberg-Marquardt and MMS algorithms for improvement of solution convergence are contained within the DC program. An example of convergence, which typically is very good, is shown in tabular form. A number of theoretical and practical solution issues are discussed, as are prospects for further development.

• 대한조선학회 특별논문집
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• 대한조선학회 2005년도 특별논문집
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• pp.63-68
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• 2005

Optimum design of the big brackets is performed through iterated 3-D FE analyses to meet the permissible limits of stress, which consumes an excessive amount of calculation time. Therefore, this study has been prepared to determine rapidly and accurately an optimum size and scantling of the big brackets at the initial design stage. The generalized slope deflection method (GSDM) based on the span point concept is applied to enhance the efficiency of iterated structural analyses. The accuracy and applicability of the present method is verified by comparing with a detail 3-D FE analysis of web frame structures. As an optimization technique, evolution strategies (ES) are applied using discrete design variables for practical design.

• 대한조선학회논문집
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• 제40권6호
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• pp.12-19
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• 2003

Corrugated bulkheads for a bulk carrier are divided into watertight bulkheads and deep tank bulkheads. Design of the watertight bulkheads is principally determined by the permissible limit of Classification and IACS requirements. But, the verification of strength through finite element analysis is indispensable for design of the deep tank bulkheads. A stage for stress evaluation of corrugated part is required for optimum structural design of the deep tank bulkheads. Since the finite element analysis for real model requires excessive amount of calculation time, in this study one corrugated structure is replaced with beam element and is idealized as 2 dimensional frame structure connected to upper and lower stool Minimum weight design of the deep tank bulkheads is performed through generalized sloped deflection method(GSDM) as direct calculation method. The purpose of this study is the development of design system for the minimization of steel weight of deep tank bulkheads as well as watertight bulkheads. Discrete variables are used as design variables for the practical design. Evolution strategies(ES) is used as an optimization technique.

• 한국경영과학회지
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• 제8권2호
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• pp.57-65
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• 1983

Despite the recent phenomenal growth in computer installations in business and increasing interests in Management Information Systems in Korea, there are basic questions remained: how are the computers utilized, what is the current state of MIS, and what are the strategies which will enhance the current state of MIS in Korea？ The purpose of this paper is to answer these questions. To begin, the current state of MIS is investigated from the aspects of MIS budget, manpower, hardware, and various softwares based on the survey of 30 major industries. The results show that the overall MIS in Korea is still remained in the primitive stage despite its ultra modern computer hardwares. The obstacles that hinders the MIS evolution in Korea seems intractable for quite a long period of time. Some strategies are suggested which can partially remove two big obstacles-shortage in qualified manpower and lack of softwares that fit Korean industries.

• BMB Reports
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• 제36권1호
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• pp.78-81
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• 2003

The prevention of cancer is one of the most important public health and medical practices of the $21^{st}$ century. We have made much progress in this new emerging field, but so much remains to be accomplished before widespread use and practice become common place. Cancer chemoprevention encompasses the concepts of inhibition, reversal, and retardation of the cancer process. This process, called carcinogenesis, requires 20-40 years to reach the endpoint called invasive cancer. It typically follows multiple, diverse and complex pathways in a stochastic process of clonal evolution. These pathways appear amenable to inhibition, reversal or retardation at various points. We must therefore identify key pathways in the evolution of the cancer cell that can be exploited to prevent this carcinogenesis process. Basic research is identifying many genetic lesions and epigenetic processes associated with the progression of precancer to invasive disease. Many of these early precancerous lesions favor cell division over quiescence and protect cells against apoptosis when signals are present. Many oncogenes are active during early development and are reactivated in adulthood by aberrant gene promoting errors. Normal regulatory genes are mutated, making them insensitive to normal regulatory signals. Tumor suppressor genes are deleted or mutated rendering them inactive. Thus there is a wide range of defects in cellular machinery which can lead to evolution of the cancer phenotype. Mistakes may not have to appear in a certain order for cells to progress along the cancer pathway. To conquer this diverse disease, we must attack multiple key pathways at once for a predetermined period of time. Thus, agent combination prevention strategies are essential to decrease cancer morbidity. Furthermore, each cancer type may require custom combination of prevention strategies to be successful.

• 한국실내디자인학회논문집
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• 제19권1호
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• pp.3-15
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• 2010

The high-rise building is a dramatic phenomenon and a powerful expression of architecture in the modern civilization. The architecture of these high-rise buildings has been developed with mutual contributions of architectural aesthetic form and advanced technologies. Architecturally the significant evolution of tall buildings from ancient towers is a "change of function" from some religious symbols to a commercial concept that has aesthetically become acceptable with the changing of modern society and culture driven by a technological evolution. Generally, this commercial function in the evolution of high-rise building is office where high-rise working style is simply a necessity to meet quantitative market demands since this style in major cities around world has been changed from low-rise to high-rise during the last several decades in influenced of the modern industrial society. To achieve optimum spaces with architectural aesthetics in the high-rise building, the design has become collaborative, requiring the input of architects, engineers, economists, and other consultants. Hence, architects must deeply understand the basic planning theories of high-rise buildings and try to find optimum planning between architectural aesthetics and other issues. For the approach, we can firstly start with measurement and analysis of the planning use situation for major planning issues of high-rise buildings in practice. Therefore, this study is to analysis Design Elements and to find commonly used planning strategies, tectonic, of high-rise building in practice. It will give a chance to confirm commonly used planning and then becomes the starting point of the planning development of high-rise buildings based on practical planning issues.

• 한국한의학연구원논문집
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• 제13권3호
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• pp.165-178
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• 2007

This article explores how non-dominant medical practitioners shape their own self-images and the identity of relevant medicine and in what ways fashioning of self-images and accompanying modalities of medical practice informs the social evolution of the medicines at specific times and over specific places, by means of the historical configuration of osteopathy and chiropractic in the UK and the US. Attention is directed onto motivations and pursuits for professional recognition and actual strategies and activities of non-dominant medicines and its practitioners by turning to historical instances such as osteopathy and chiropractic in the UK and the US, not least drawing focus on professional desires with regard to circumstances it faces within and without. Some non-dominant medicines as a way with which to acquire and protect the exclusive monopoly of its knowledge and practical skills, adopted various forms of professionalism project, as dominant biomedical groups pressed up non-dominant medicines by virtue of marginalizing tactics. Meanwhile, non-dominant medicines took somewhat distinctive professionalisation strategies from each other. Strategies they took were diversified depending on medical philosophy, healing modality, the degree of occupational solidarity embodied as forms of medical organisation, and especially vocational aspiration and prospect. Change of socio-medical culture and the state's policy seems to have wielded critical influenceon the determination of the ups and downs of non-dominant medicines. From the perspective of long-term time span, dominant biomedicine eventually did not have much influence on the ups and downs of marginalized medicines in so far as in the case of osteopathy and chiropractic in Englandand the U. S.