• Journal of Information Processing Systems
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• v.13 no.2
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• pp.370-384
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• 2017

The image segmentation is the most important operation in an image processing system. It is located at the joint between the processing and analysis of the images. Unsupervised segmentation aims to automatically separate the image into natural clusters. However, because of its complexity several methods have been proposed, specifically methods of optimization. In our work we are interested to the technique SFLA (Shuffled Frog-Leaping Algorithm). It's a memetic meta-heuristic algorithm that is based on frog populations in nature searching for food. This paper proposes a new approach of unsupervised image segmentation based on SFLA method. It is implemented and applied to different types of images. To validate the performances of our approach, we performed experiments which were compared to the method of K-means.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.3
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• pp.8-15
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• 2011

The computer-based simulation tools are currently used overwhelmingly to simulate the performance of automotive designs. Then, the search for an optimal solution that satisfies a number of performance requirements usually involves numerous iterations among several simulation tools. Therefore, meta-modeling techniques are becoming widely used to build approximations of computationally expensive computer analysis tools. The set-based approach proposed in the first report of a four-part paper has been a test bed for the innovation of vehicle structure design process in the Structural Design and Fabrication Committee of JSAE(Society of Automotive Engineers of Japan). In the second report, the proposed design approach is illustrated with a side-door impact beam design example using meta-modeling techniques.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7149-7154
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• 2013

Objective: Increasing scientific evidence suggests that common variants in the PALB2 gene may confer susceptibility to breast cancer, but many studies have yielded inconclusive results. This meta-analysis aimed to derive a more precise estimation of the relationship between PALB2 genetic variants and breast cancer risk. Methods: An extensive literary search for relevant studies was conducted in PubMed, Embase, Web of Science, Cochrane Library, CISCOM, CINAHL, Google Scholar, CNKI and CBM databases from their inception through September 1st, 2013. A meta-analysis was performed using the STATA 12.0 software and crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Results: Six case-control studies were included with a total of 4,499 breast cancer cases and 6,369 healthy controls. Our meta-analysis reveals that PALB2 genetic variants may increase the risk of breast cancer (allele model: OR>1.36, 95%CI: 1.20~1.52, P < 0.001; dominant model: OR>1.64, 95%CI: 1.42~1.91, P < 0.001; respectively). Subgroup analyses by ethnicity indicated PALB2 genetic variants were associated with an increased risk of breast cancer among both Caucasian and Asian populations (all P < 0.05). No publication bias was detected in this meta-analysis (all P > 0.05). Conclusion: The current meta-analysis indicates that PALB2 genetic variants may increase the risk of breast cancer. Thus, detection of PALB2 genetic variants may be a promising biomarker approach.

• The Korean Journal of Air & Space Law and Policy
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• v.11
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• pp.405-414
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• 1999

• Communications of Mathematical Education
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• v.32 no.3
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• pp.407-433
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• 2018

In order to analyze textbooks from a discursive approach, the purpose of this study is to structuralize an analytic framework based on previous literature review and apply it to analyzing the meanings and their syntheses developed by words and visual mediators appeared in the definition of graph in first-year middle school textbooks. The discursive approach consists of the communicational approach developed by Sfard(2008) and the systemic functional linguistics developed by Halliday(1985/2004). In this study, ideational meta-functions for ideational meanings and interpersonal meta-functions for interpersonal meanings were employed to analyze the meanings produced by words and visual mediators in textbooks, whereas textual meta-functions for textual meanings were used for analyzing the synthesized relationships between words and visual mediators. Results show that first, density in mathematical discourse was very high and subjects in mathematical activities were ambiguous in the ideational meanings of words, and behavior aspect was more emphasized than thinking aspect in the interpersonal meanings of words which request student participations. In the case of ideational meanings of visual mediators, there was a lack of narrative diagrams, whereas there were qualitative differences in the case of offer. Second, there was a need for promoting a wide range of diverse synthetic relationships between words and visual mediators for developing enriched mathematical meanings through the varying uses like specification, explanation, similarity, and complement. These results are so important that they provide a new analytic framework from a discursive approach to textbook analysis because not only words, but also visual mediators are analyzed as tools for producing meanings in mathematics textbooks and their synthetic relationships are also examined.

• The Journal of the Korea Contents Association
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• v.16 no.4
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• pp.741-756
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• 2016

This study is to identify the effectiveness of English literature in reading instruction using meta-analysis of advanced researches. 80 studies published in Korea were selected for this research wherein the studies are in experimental nature on reading instruction using English literature. The result of the meta-analysis are as follows: Reading instruction with English literature for early children in kindergartens and primary schools showed statistically significant positive effects in both reading abilities and affective domains, in particular for younger children from kindergartners to 2nd graders of primary school. It was more effective when the instructor used top-down approach than bottom-up or balanced approach. No significant coorelation was found between the number of English stories and the students' linguistic ability. Diverse activities tailored to students' need are turned out to be more effective than using same old activities with more stories.

• Journal of Korean Institute of Industrial Engineers
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• v.33 no.1
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• pp.86-98
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• 2007

This paper presents a heuristic algorithm for the traveling salesman problem with time windows (TSPTW). Aniterative insertion algorithm as a constructive search heuristic and a hybrid meta heuristic combining simulatedannealing and tabu search with the randomized selection of 2-interchange and a simple move operator as animproving search heuristic are proposed, Computational tests performed on 400 benchmark problem instancesshow that the proposed algorithm generates optimal or near-optimal solutions in most cases. New best knownheuristic values for many benchmark problem sets were obtained using the proposed approach.

• International Journal of Contents
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• v.10 no.3
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• pp.73-83
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• 2014

Participants in Open Source Software (OSS) development projects usually contribute voluntarily without expecting direct compensation for their work. One of the central puzzles raised by the success of OSS is the motivation of the participants; why top-notch programmers choose to write software that is released for no fee. In order to respond to this peculiarity employing a meta-research method, we first identify and review theoretical perspectives from diverse disciplines including economics, sociology, political science, anthropology, psychology, and management. Then, we suggest a comprehensive framework that provides a holistic understanding of the puzzle in question. Reviewing key empirical studies based on the suggested framework, we also suggest a future research agenda.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.141-144
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• 2007

Given a number of training data, a traditional BPN is normally trained by minimizing the absolute difference between target outputs and approximate outputs. When BPN is used as a meta-model for inequality constraint function, approximate optimal solutions are sometimes actually infeasible in a case where they are active at the constraint boundary. The paper describes the development of the efficient BPN based meta-model that enhances the constraint feasibility of approximate optimal solution. The modified BPN based meta-model is obtained by including the decision condition between lower/upper bounds of a constraint and an approximate value. The proposed approach is verified through a simple mathematical function and a ten-bar planar truss problem.

• Structural Engineering and Mechanics
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• v.60 no.6
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• pp.1093-1117
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• 2016

Global sensitivity analysis (GSA) has been widely used to investigate the sensitivity of the model output with respect to its input parameters. In this paper a new single-solution search optimization algorithm is developed based on the GSA, and applied to the size optimization of truss structures. In this method the search space of the optimization is determined using the sensitivity indicator of variables. Unlike the common meta-heuristic algorithms, where all the variables are simultaneously changed in the optimization process, in this approach the sensitive variables of solution are iteratively changed more rapidly than the less sensitive ones in the search space. Comparisons of the present results with those of some previous population-based meta-heuristic algorithms demonstrate its capability, especially for decreasing the number of fitness functions evaluations, in solving the presented benchmark problems.