• Nuclear Engineering and Technology
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• v.53 no.11
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• pp.3675-3684
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• 2021

Human reliability analysis (HRA) is a proactive approach to model and evaluate human systematic errors, and has been extensively applied in various complicated systems. Dependence assessment among human errors plays a key role in the HRA, which relies heavily on the knowledge and experience of experts in real-world cases. Moreover, there are ofthen different types of uncertainty when experts use linguistic labels to evaluate the dependencies between human failure events. In this context, this paper aims to develop a new method based on linguistic hesitant fuzzy sets and the technique for human error rate prediction (THERP) technique to manage the dependence in HRA. This method handles the linguistic assessments given by experts according to the linguistic hesitant fuzzy sets, determines the weights of influential factors by an extended best-worst method, and confirms the degree of dependence between successive actions based on the THERP method. Finally, the effectiveness and practicality of the presented linguistic hesitant fuzzy THERP method are demonstrated through an empirical healthcare dependence analysis.

• Industrial Engineering and Management Systems
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• v.7 no.3
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• pp.266-287
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• 2008

To manage collaborative negotiation in software system design, we have built a socio-technical argument-based negotiation management approach by integrating a Socio-technical Co-construction Process (STCP) with an Argument-based Negotiation Process (ABNP). This paper reviews relevant research work and presents each step of this approach. The STCP provides rich contextual information of technical decisions and social interactions in a system design process. The ABNP provides STCP with a negotiation management and conflict resolution strategy by guiding software engineers to generate, exchange and evaluate their argument claims in negotiation activities. In addition, this paper describes a prototype system which implements this new approach using the advanced Web-based software technologies with the goal of demonstrating how to systematically enhance the negotiation management capabilities in a dynamic socio-technical framework.

• Journal of Power Electronics
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• v.11 no.1
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• pp.90-96
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• 2011

Congestion management is one of the most challenging aspects in the recently deregulated electricity markets. FACTS devices have been shown to be an efficient alternative to control the flow of power in lines, resulting in increased loadability, lower system loss and a reduced cost of production. In this paper, the application of a static series synchronous compensator (SSSC) for the purpose of congestion management of power systems has been studied. A sensitivity-based analysis method is utilized for effective determination of the SSSC location in an electricity market. The method is topology based and it is independent of the system operation point. A power injection p-model is developed for the SSSC in this study. Numerical results based on the modified IEEE 14 bus system with/without the SSSC demonstrate the feasibility as well as the effectiveness of the SSSC for congestion management in a network. The results obtained when using the SSSC to improve system transfer capability and congestion management is encouraging.

• The Journal of Information Systems
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• v.14 no.3
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• pp.17-22
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• 2005

Location management is very important in location-based services to provide services to the mobile users like banking, city guides and many more. Ubiquitous and mobile devices are the source of data in location management and its significant operations are update and search method. Some studies to improve these were presented by using optimal sequential paging, location area scheme and hierarchical database scheme. In addition, not all location services have the same access methods on data and it lead to difficulties of providing services. A proposed location management of multi-agent architecture is presented in this study. It shows the coordination of the agents on the distributed database of location-based services. The proposal focuses on the location management of the mobile object presented in a hierarchical search and update. Also, it uses a nearest neighbor technique for efficient search method of mobile objects.

• Journal of Korean Institute of Industrial Engineers
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• v.43 no.3
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• pp.192-202
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• 2017

This study develops a text spam filtering system for Facebook based on two variable categories: keywords learned from Instagram and meta-information of Facebook posts. Since there is no explicit labels for spam/ham posts, we utilize hash tags in Instagram to train classification models. In addition, the filtering accuracy is enhanced by considering meta-information of Facebook posts. To verify the proposed filtering system, we conduct an empirical experiment based on a total of 1,795,067 and 761,861 Facebook and Instagram documents, respectively. Employing random forest as a base classification algorithm, experimental result shows that the proposed filtering system yield 99% and 98% in terms of filtering accuracy and F1-measure, respectively. We expect that the proposed filtering scheme can be applied other web services suffering from massive spam posts but no explicit spam labels are available.

• ETRI Journal
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• v.33 no.1
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• pp.60-70
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• 2011

Software is completely exposed to an attacker after it is distributed because reverse engineering is widely known. To protect software, techniques against reverse engineering are necessary. A code encryption scheme is one of the techniques. A code encryption scheme encrypts the binary executable code. Key management is the most important part of the code encryption scheme. However, previous schemes had problems with key management. In an effort to solve these problems in this paper, we survey the previous code encryption schemes and then propose a new code encryption scheme based on an indexed table. Our scheme provides secure and efficient key management for code encryption.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2002.05a
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• pp.306-311
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• 2002

This paper propose a personalized defection detection and prevention procedure based on the observation that potential defectors have tendency to take a couple of months or weeks. For this purpose, possible states of customer behavior are determined from past behavior data using SOM (Self-Organizing Map). For the evaluation of the proposed procedure, a case study has been conducted for a Korean online game site. The result demonstestes that the proposed procedure can assist defection prevention effectively and detect potential defectors without deterioration of prediction accuracy comparison to prediction by MLP. Our procedure can be applied to various service industries that can capture fluent customer behavior data such as telecommunications, internet access services, and content services, too.

• Journal of the Korean Society of Safety
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• v.20 no.4 s.72
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• pp.154-161
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• 2005

As disasters in the modem era become a large scale and complexity, no single entity can manage them. Instead collective cooperation between civilian, enterprise, school and government sectors is significantly needed, along with a well prepared mechanism. Thus, I attempt to construct the applicable network of civilian, enterprise, school and government sectors for disaster management through exemplary case studies of established countries as well as Korea's current operations and its drawbacks, based upon a networking design of disaster management organizations as belows: Firstly, it is cooperation and coordination among relevant organizations that are required essentially in the new era, in view of formative condition of necessary environment for civil participation. The cooperation and coordination can be made only through the network of civilian, enterprise, school and government sectors. Secondly, in order to build up the network, major roles and tasks which should be done by civilian, enterprise, school and government sectors respectively are listed based upon a stage of disaster management. Thirdly, operation models of a safety monitoring unit, a disaster prevention unit, a emergency response unit, and a rehabilitation unit are proposed in line with the network of civilian, enterprise, school and government sectors in regional base.

• Journal of Industrial Convergence
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• v.13 no.4
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• pp.29-37
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• 2015

The main purpose of this study was to examine the determinants of organizational form in the sport organization. This study found that the leader's quality had positive influences on the personality, knowledge ability, and change management. Based on the analysis of three hundred fifty cases, the following results were found. First, the leader's quality and personality had the significant effects on knowledge-Based management in the sports organizations. Second, the leader's knowledge competence and the transformative leadership had the significant effects on knowledge-Based management in the sports organizations. Third, the leader's knowledge :management had the significant effects on organiztional behavior in the sports organizations.

• Korean Journal of Community Nutrition
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• v.21 no.1
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• pp.12-24
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• 2016

Objectives: The objectives of the study were to investigate the school nutrition teachers' perception on their job and to find out recommendations needed for its improvement in order to provide a quality foodservice and nutrition education at schools. Methods: A total of 219 school nutrition teachers in Seoul were surveyed using selfadministered questionnaires. Results: The perceived importance of the 16 job duties was rated 3.8 based on a 5-point scale (1: very unimportant - 5: very important). The importance of six duties including nutrition management, production management, nutrition education, and food safety management were rated over 4 point but that of record-keeping for documents, official reporting, and service management was rated the lowest. Importance-Performance Analysis showed that nutrition management, receiving/storage management, production management, menu management, food safety management, and equipment/facilities management should be emphasized to maintain the current performance of duties. The performance of the nutrition education and counseling needed to be improved since the importance scores were greater than average but the performance scores were lower than the average. Official reporting and miscellaneous jobs were rated the highest for simplification need. More than half of the respondents agreed that equipment/facilities management, miscellaneous jobs, service staff supervision, and service line supervision could be allocated to other school departments. Conclusions: School nutrition teachers should invest more time and resources on their core job duties such as nutrition management, production management, food safety management, and nutrition education for providing quality foodservice and nutrition education. To reflect the environmental changes of school foodservice, a reasonable staffing index of school nutrition teachers needs to be developed. In addition, hiring an assistant or implementing school nutrition teacher internship programs can be useful to reduce workloads of the nutrition teachers.