• Journal of Communications and Networks
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• 제17권3호
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• pp.306-320
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• 2015

Due to an explosive growth in services running in different datacenters, there is need for service selection and routing to deliver user requests to the best service instance. In current solutions, it is generally the client that must first select a datacenter to forward the request to before an internal load-balancer of the selected datacenter can select the optimal instance. An optimal selection requires knowledge of both network and server characteristics, making clients less suitable to make this decision. Information-Centric Networking (ICN) research solved a similar selection problem for static data retrieval by integrating content delivery as a native network feature. We address the selection problem for services by extending the ICN-principles for services. In this paper we present Queue and Latency, a network-driven service selection algorithm which maps user demand to service instances, taking into account both network and server metrics. To reduce the size of service router forwarding tables, we present a statistical method to approximate an optimal load distribution with minimized router state required. Simulation results show that our statistical routing approach approximates the average system response time of source-based routing with minimized state in forwarding tables.

• 한국과학교육학회지
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• 제30권4호
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• pp.429-436
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• 2010

이 연구에서는 예비과학교사들이 임용시험의 과학교육학 내용 학습에서 겪는 어려움을 조사하였다. 우선 중등교사 임용시험을 준비하는 한 인터넷 카페의 게시판에 2008년 1월부터 2009년 6월 사이에 게시된 질문들의 내용 영역을 분석하였다. 또한, 임용시험을 마친 예비교사 39명을 대상으로 설문조사를 실시하였다. 내용 영역 분석에 사용한 평가틀은 한국교육과정 평가원과 한국과학교육학회에서 개발한 것이었다. 인터넷 카페의 질문을 분석한 결과, '과학철학과 과학사'와 '과학교수학습이론과 수업모형'에 대한 질문이 가장 많았다. 설문 조사 결과, 예비교사들은 과학철학 관련 내용이 가장 어렵다고 응답하였고, 과학 교수학습 이론이나 수업모형의 적용이 어렵다고 응답하였다. 이상의 결과에 기초하여 교육학적 함의를 논의하였다.

• 품질경영학회지
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• 제27권3호
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• pp.125-141
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• 1999

Bayesian inference and model selection method for software reliability growth models are studied. Software reliability growth models are used in testing stages of software development to model the error content and time intervals between software failures. In this paper, we could avoid the multiple integration by the use of Gibbs sampling, which is a kind of Markov Chain Monte Carlo method to compute the posterior distribution. Bayesian inference and model selection method for Jelinski-Moranda and Goel-Okumoto and Schick-Wolverton models in software reliability with Poisson prior information are studied. For model selection, we explored the relative error.

• ETRI Journal
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• 제31권4호
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• pp.408-418
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• 2009

Adopting an encryption function in voice over Wi-Fi service incurs problems such as additional power consumption and degradation of communication quality. To overcome these problems, a partial encryption (PE) algorithm for compressed speech was recently introduced. However, from the security point of view, the partial encryption sets (PESs) of the conventional PE algorithm still have much room for improvement. This paper proposes a new selection method for finding a smaller PES while maintaining the security level of encrypted speech. The proposed PES selection method employs the perceptual evaluation of the speech quality (PESQ) algorithm to objectively measure the distortion of speech. The proposed method is applied to the ITU-T G.729 speech codec, and content protection capability is verified by a range of tests and a reconstruction attack. The experimental results show that encrypting only 20% of the compressed bitstream is sufficient to effectively hide the entire content of speech.

• 한국패류학회지
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• 제19권2호
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• pp.89-93
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• 2003

In this study, the food selection of abalone, Haliotis discus hannai, on four various diets, Ulva pertusa, Laminaria japonica, Navicula spp., and artificial diet, was investigated. The abalones in Ulva pertusa and Navicula spp groups had the higher migration rate than the others. The artificial group had the lowest migration rate. As to the growth, Ulva pertusa group had the highest daily increment and the growth rate, which is 120.7 ${\mu}$m and 2.41%. The value of Navicula spp. group is 102.0 ${\mu}$m and 2.04% and that of Laminaria japonica group is 88.7 ${\mu}$m and 1.77%. The lowest one is 81.7 ${\mu}$m and 1.63%, which appeared at the artificial diet group. We suggest that, when breeding Haliotis discus hannai and the diets which is easy to be ingested and digested, as well as contains much nutrient content, should be used. If the artificial diet is used, it should contain low concentration of flesh-eating content.

• International Journal of Computer Science & Network Security
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• 제21권1호
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• pp.40-48
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• 2021

Content-Based Image Retrieval (CBIR) system plays a vital role to retrieve the relevant images as per the user perception from the huge database is a challenging task. Images are represented is to employ a combination of low-level features as per their visual content to form a feature vector. To reduce the search time of a large database while retrieving images, a novel image retrieval technique based on feature dimensionality reduction is being proposed with the exploit of metaheuristic optimization techniques based on Genetic Algorithm (GA), Extended Binary Cuckoo Search (EBCS) and Whale Optimization Algorithm (WOA). Each image in the database is indexed using a feature vector comprising of fuzzified based color histogram descriptor for color and Median binary pattern were derived in the color space from HSI for texture feature variants respectively. Finally, results are being compared in terms of Precision, Recall, F-measure, Accuracy, and error rate with benchmark classification algorithms (Linear discriminant analysis, CatBoost, Extra Trees, Random Forest, Naive Bayes, light gradient boosting, Extreme gradient boosting, k-NN, and Ridge) to validate the efficiency of the proposed approach. Finally, a ranking of the techniques using TOPSIS has been considered choosing the best feature selection technique based on different model parameters.

• 한국콘텐츠학회논문지
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• 제12권8호
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• pp.136-145
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• 2012

본 연구는 중국 광주지역 대학생 시청자들의 한국 드라마 선호요인이 한국이나 한국인에 대한 이미지에 어떤 영향을 미치는지를 살펴보았다. 연구결과를 요약하면 다음과 같다. 첫째, 중국 대학생 시청자들의 한국드라마 선호요인은 드라마의 '주제와 내용', 드라마의 '연출과 음악', 드라마 '배우의 스타일' 등 3가지 유형으로 나타났는데 그 중 드라마의 '주제와 내용' 요인이 가장 영향력이 큰 것으로 나타났다. 둘째, 중국대학생 시청자들의 한국과 한국인에 대한 이미지 요인은 '한국인의 정시 및 관광지 이미지 요인', '한국의 문화적 요인', '한국인의 스타일 요인' 등 3가지 유형으로 나타났다. 중국 대학생 시청자들이 드라마를 통해 한국에 대한 현대적 가치에 가장 큰 관심을 보이고 있는 것으로 생각되며, 나아가 한국은 중국과 근접해 있어 문화적으로 친근하고 유교 문화권이라는 유대감 속에서 한국을 호감 가는 국가로 인식하고 있는 것으로 나타났다. 셋째, 한국드라마의 선호요인이 한국의 국가이미지에 미치는 영향에 대해서는 한국인의 정시 및 관광지 이미지 요인, 한국의 문화적 요인, 한국인의 스타일요인 모두에서 긍정적인 영향을 미치는 것으로 나타났다. 즉 이러한 결과는 중국 광주지역 대학생들이 한국드라마 선호요인, 즉 한국드라마의 주제와 내용, 연출과 음악, 배우라는 요인에 초점을 두고 시청하고, 드라마를 평가하며, 한국 드라마 시청을 통하여 한국에 대한 친근감을 형성하게 되고, 나아가 한국의 대중문화에 대한 관심과 선호를 높일 수 있다는 가능성을 보여주었다.

• 한국식품영양학회지
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• 제20권2호
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• pp.226-239
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• 2007

The purpose of this study was to identify the problems related to the purchasing processes of school foodservices that should be corrected for the food service safety, by examining the purchasing processes and the status of supplier selection. A questionnaire was given to 300 dietitians working at self-operated food services. Ninety-eight responses, excluding incomplete answers, were used for the statistical analysis. The survey consisted of three parts: the general characteristics of the school foodservice and dietitian, purchasing processes and supplier selection, and the purchase specifications. We found that 84% of the contract was made by informal purchasing, and the contract period was 6 months or one year. For supplier selection, problems related to the document screening systems were the superficiality of the content(45.7%) and the absence or lack of clarity of the appraisal criteria(34.8%). The important factors for the facility and equipment standards of suppliers were included unclear evaluation methods for content(41.1%) and inappropriate appraisal lists(21.1%), while unclear evaluation methods for content(41.9%) and absence or lack of clarity of the appraisal criteria(20.4%) were the problems pertaining to the supplier evaluation checklist. When using the Food Labeling Standards to select suppliers, confirmation of the sell-by date and the storage method had the highest score at 3.85 out of 5. For supplier selection, only 25% of the contract was made by using the purchase specifications. The levels of satisfaction of with Kimchi and rice cakes suppliers were significantly different according to employment type and educational background, respectively. Depending on working experiences, satisfaction was significantly different for the use of document screening, as a standard for the selection and management of suppliers, and for the facility and equipment standards of suppliers, The use of purchase specifications was different by employment type, while the use of purchase specifications for contracts was different by working experience. These results imply that the specialization of suppliers is necessary to unsure food safety. Therefore, the objective methods to evaluate the suppliers should be developed by the government, and appropriate education programs for dietitians should be prepared to enhance the utilization of purchase specifications.

• 한국조경학회지
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• 제36권1호
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• pp.70-79
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• 2008

The purpose of this study is to construct the fundamental data for setting a valid viewpoint as the base of landscape planning and management practices. To do this, we analyzed the preceding dissertations and landscape plan reports which presented the selection criteria of viewpoint. 37 research samples containing the criteria of viewpoint were investigated. The selection criteria and trends of viewpoint were analyzed as follows : Firstly, by analyzing the preceding researches we were able to grasp the criteria that had been used to set viewpoint. Secondly, we investigated the differences in criteria of selecting the viewpoint according to the research type, research time and view object. Finally, we analyzed the trends of viewpoint selection criteria and classified the characteristics and selection criteria of viewpoint based on an overview of the research content. It can be concluded that the criteria of viewpoint are intimately linked to the view object, the purpose and role of viewpoint which is related to the landscape planning and management practices. According to this study, we can find that the selection criteria and trends of viewpoint have been used in the research related to the view plane following the 1990's. Hereafter, additional research and the comparisons with researches abroad is necessary to set the objective selection criteria of viewpoint.

• 산업경영시스템학회지
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• 제42권3호
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• pp.217-231
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• 2019

The purpose of this study is to analyze the factors influencing consumers' selection of web-toon service through AHP (Analytic Hierarchy Process) analysis and to provide the strategy of web-toon service. To accomplish this study, theories, existing research and references related to AHP were sufficiently examined and selected the factors in the selection criteria. Surveys from consumers who used the web-toon service were conducted with selected factors. Through this, the results were analyzed by AHP analysis to find out the weighting values and the differences were examined and analyzed. The highest weighting factor in the first layer that consists of web-toon service was cinematic quality. The cinematic quality was the most important factor in the selection criteria of customers who use the web-toon service regardless of their preferred genre. Furthermore, it was confirmed that the weighting value or ranking changed in the second layer by genre. In this study, the effective basis of strategy were suggested by ranking the quantitative selection factors according to the preferred genre of consumers using web-toon services. In addition, This research provides some practical implications. That is, the web-toon service provider can easily recognize and respond to the customer's requirements, which factors are important when the customer selects a specific genre from the web-toon genre.