• Journal of the Korean Data and Information Science Society
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• v.25 no.5
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• pp.1127-1135
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• 2014

Genome-wide association studies (GWAS) are designed to discover genetic variants such as single nucleotide polymorphisms (SNPs) that are associated with human complex traits. Although there is an increasing interest in the application of GWAS methodologies to population-based cohorts, many published GWAS have adopted a case-control design, which raise an issue related to a sampling bias of both case and control samples. Because of unequal selection probabilities between cases and controls, the samples are not representative of the population that they are purported to represent. Therefore, non-random sampling in case-control study can potentially lead to inconsistent and biased estimates of SNP-trait associations. In this paper, we proposed inverse-probability of sampling weights based on disease prevalence to eliminate a case-control sampling bias in estimation and testing for association between SNPs and quantitative traits. We apply the proposed method to a data from the Korea Association Resource project and show that the standard estimators applied to the weighted data yield unbiased estimates.

• Journal of the Korean Operations Research and Management Science Society
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• v.16 no.2
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• pp.14-35
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• 1991

The purpose of this study is to develop an efficient exact algorithm for the problem of scheduling n in dependent jobs on m unequal parallel processors to minimize makespan. Efficient solutions are already known for the preemptive case. But for the non-preemptive case, this problem belongs to a set of strong NP-complete problems. Hence, it is unlikely that the polynomial time algorithm can be found. This is the reason why most investigations have bben directed toward the fast approximate algorithms and the worst-case analysis of algorithms. Recently, great advances have been made in mathematical theories regarding Lagrangean relaxation and the subgradient optimization procedure which updates the Lagrangean multipliers. By combining and the subgradient optimization procedure which updates the Lagrangean multipliers. By combining these mathematical tools with branch-and-bound procedures, these have been some successes in constructing pseudo-polynomial time algorithms for solving previously unsolved NP-complete problems. This study applied similar methodologies to the unequal parallel processor problem to find the efficient exact algorithm.

• Journal of the Korean Operations Research and Management Science Society
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• v.16 no.2
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• pp.13-35
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• 1991

The purpose of this study is to develop an efficient exact algorithm for the problem of scheduling n in dependent jobs on m unequal parallel processors to minimize makespan. Efficient solutions are already known for the preemptive case. But for the non-preemptive case, this problem belongs to a set of strong NP-complete problems. Hence, it is unlikely that the polynomial time algorithm can be found. This is the reason why most investigations have bben directed toward the fast approximate algorithms and the worst-case analysis of algorithms. Recently, great advances have been made in mathematical theories regarding Lagrangean relaxation and the subgradient optimization procedure which updates the Lagrangean multipliers. By combining and the subgradient optimization procedure which updates the Lagrangean multipliers. By combining these mathematical tools with branch-and-bound procedures, these have been some successes in constructing pseudo-polynomial time algorithms for solving previously unsolved NP-complete problems. This study applied similar methodologies to the unequal parallel processor problem to find the efficient exact algorithm.

• 한국IT서비스학회:학술대회논문집
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• 2006.11a
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• pp.593-599
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• 2006

Including technical device and general information system, the information-technical(IT) system is defined as the technical system for acquiring, processing, storing and transferring information to a person. This paper presents Knowledge-based Heuristic Evolution Model for creating the advanced information-technical system. This Evolution Model is derived from the historical review on definition of evolution, the research on the architecture of the general IT system, history of IT system, technology innovation theory and multi-case study research. The evolution model is applicable to the conceptual creation of the advanced product in R&D organization requiring development methodologies like rapid-prototyping to develop next generation product. For the detailed theoretical construction and practical application of Evolution Model, the case study research based on action research is performed. the object of the case study is mobile device, especially mobile hand-held phone. Thus, we obtain the Evolution Model for creating the advanced information-technical system.

• Journal of Korean Elementary Science Education
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• v.32 no.3
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• pp.260-268
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• 2013

With the development of science and technology, an effort to investigate the current research trend of elementary science education will lead to future directions for elementary science education. This study set out to analyze papers published in Elementary Science Education by quantity, subject and methodology for the last ten years. The results were as follows: First, the number of papers has continuously increased for the last 30 years. Second, as for categorization by the functions of elementary science education, the number of papers was mainly published in the field of teacher education, which was followed by learning processes and teaching methods in the order. Third, in the field of the research subjects of elementary science education, many researches were conducted on scientific inquiries and concepts traditionally emphasized in elementary science education, and on gifted education recently implemented as part of national policy. Fourth, as for categorization by the methodologies of elementary science education, a survey study was the most popular, being followed by experimental study and literature study in the order. In recent years, researches based on the case study methodology have visibly grown in numbers, which seems to part of efforts to find implications with new methodologies among researchers facing limitations with the old ones in the middle of uniqueness called education.

• Environmental Engineering Research
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• v.24 no.1
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• pp.63-73
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• 2019

This study suggests a method for calculating the benefits of water pipe renewal based on an estimate of the water supply suspension risk. The proposed method based on five benefit items is more direct and specific than other benefit estimation methods. In addition, a methodology evaluating the economics of pipe renewal based on pipe failure rate is proposed for estimating the optimal renewal point from an economic perspective. By estimating the optimal renewal period based on a yearly benefit cost ratio per pipe in a case study area, it was possible to draft an optimal renewal plan for the subject region from an economic perspective. Compared with other methodologies, a reasonable optimal renewal period was derived from an economic point of view. The result of this study may be used to develop future water pipe renewal plans. Moreover, the proposed methodologies and results derived from this study can be applied to asset management plans.

• Journal of The Korean Digital Architecture Interior Association
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• v.13 no.4
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• pp.13-23
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• 2013

Steven Holl is outstanding architect who has been applied his phenomenological thinking to his works. he has been reported that he had adhered to focus his interest on coherent phenomenological theme and sublimated his architectural concept succesfully. This study focuses on relationship how phenomenological concept has common ground with architectural parts and with the study on phenomenological application methodology of architectonics of Steven Holl. In the case of Holl, with the theme of sense and flesh, he molds phenomenologically sensitive space. His works contains coherent phenomenolgical concepts such as distrust of rationality, synthesis of consciousness, and qeustions of perception. The Methodologies of connection with environment(nature or bridge), regional values, placeness, light and time are considered in his works(books and architectural works) as anchoring, interwining and parallax for phenomenological process in his concepts. His methodologies of enlisted works contain many valuable concepts of phenomenological intuition and would be applicable to contemporary and future architecture for humanism.

• The Journal of Society for e-Business Studies
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• v.9 no.2
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• pp.87-108
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• 2004

The current construction industry mainly uses paper-based construction documents which are produced during the whole life cycle. The paper-based information hinders to reuse the construction information, due to the inefficiency to exchange and share the construction information between designers and constructors. To overcome these problems, construction CALS/EC (Continuous Acquisition and Life Cycle Support/Electronic Commerce) has been proposed by the government. It supports efficient reusing, sharing and exchanging the construction information using digitalized drawings and documentations. This study intends to show the future applying methodologies of using the standardized key technologies in the construction CALS/EC based on the case study of Korea and several countries.

• Journal of the Korean Institute of Educational Facilities
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• v.18 no.1
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• pp.29-38
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• 2011

ent years, the change of urban function and the decrease in birth rate have given rise to merge, abolition and relocation of the existing schools. This study explores the possibilities for various land utilizations of relocated school sites, using the trial case of 'A' elementary school in Eun-pyeong gu, Seoul. 'A' elementary school has happened transfer plan due to the urban development project of the redevelopment area, Eun-pyeong gu in Seoul. Firstly, it studies the land use categories and the development methodologies of 7 relocated school sites happened in Seoul. In addition, it analyzes the land utilization after relocation, development principals, area, building usage and changes in land use regulation. Finally, it proposes the commercial exploitation of school site targeting 'A' elementary school site. Throughout the profit analysis, this study concludes that it is available to exploit the relocated school sites by the variety of development methodologies, especially in a metropolis like Seoul.

• The Journal of Information Systems
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• v.31 no.3
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• pp.1-18
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• 2022

Purpose The purpose of this study is to analize a psychological and behavioral mechanism for using profile picture management in digital service such as social network service. Profile picture management falls under metadata management and is performed only by those who want it. This means that it, is one of the typical makeup-type digital shadow works (DSWs) which have not been studied yet. Design/methodology/approach This study adopts ground theory method(GTM) as research methodology. GTM, which is one of qualitative methodologies, is for developing theories while most survey based methodologies, which are well adopted in much research for information systems, are for validation of theories. By interviewing ten users, the data are collected and analyzed by open coding, axis coding with paradigm model, and selective coding. Findings In result, 39 codes are found and classified into 29 sub classes and 15 classes. These 15 classes are organized by paradigm model which derives core code of profile picture management as 'voluntary management tasks to experience small pleasures with intermittent attention'. Finally, based on the paradigm model and the core code, the story line, which can explain profile picture management, is suggested.