• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.589-592
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• 2002

The CCM (Continuous Conduction Mode) boost topology is generally used in the PFC (Power Factor Correction) regulator of household air-conditioning systems. There are three kinds of power devices-bridge rectifier diodes, FRDs (Fast Recovery Diodes), and IGBTs (or MOSFETs) - used In a boost PFC regulator. Selecting the appropriate device is very cumbersome work, specially, in the case of FRDs and IGBTs, because there are several considerations as described below: 1) High frequency leakage current regulation (conducted and radiated EMI regulation) 2) Power losses and thermal design 3) Device cost. It should be noted that there are trade-offs between the power loss characteristic of 2) and the other characteristics of 1) and 3). This paper presents a detailed evaluation by using several types of power devices, which can be unintentionally used, to show that optimal selection can be achieved. Based on the given thermal resistances, thermal analysis and design procedures are also described from a practical viewpoint.

• 품질경영학회지
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• 제38권4호
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• pp.531-539
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• 2010

Mega-Y project is very important for a company to gain a competitive advantage in markets or to achieve drastic change in the internal processes. It stems from the company strategy and annual management goals or key performance measures, and is proceeded by the cross-functional team. This paper presents the success factors and implementation process of the Mega-Y projects. The implementation process is presented in 5 steps, including project selection, cross-functional team building, establishment of the master plan, development and execution of sub-projects, and project completion. A case study on the cost reduction project of aircraft development is presented to help for the practitioners to deploy the implementation process introduced in this paper.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.54-58
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• 2002

Mean curvature diffusion (MCD) is a selective smoothing technique that promotes smoothing within a region instead of smoothing across boundaries. By using mean curvature diffusion, noise is eliminated and edges are preserved. In this paper, we propose methods of automatic parameter selection and implementation for the MCD model coupled to min/max flow. The algorithm has been applied to high resolution aerial images and the results show that noise is eliminated and edges are preserved after removal of noise.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.81-81
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• 2002

Classification is considered as one of the processes of extracting attributes from satellite imagery and is one of the usual functions in the commercial satellite image processing software. Accuracy of classification plays a key role in deciding the usage of its results. Many tremendous efforts far the higher accuracy have been done in such fields; training area selection, classification algorithm. Our research is one of these effort in different manners. In this research, we conduct classification using multiple satellite image data and evidential approach. We statistically consider the posterior probabilities and certainty in maximum likelihood classification and methodologically Dempster's orthogonal sums. Unfortunately, accuracy for the whole data sets has not assessed yet, but accuracy assessments in training fields and check fields shows accuracy improvement over 10% in overall accuracy and over 0.1 in kappa index.

• Educational Technology International
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• 제15권2호
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• pp.201-215
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• 2014

The design project of a technology product provides an opportunity for students to experience the inter-connectedness of academic information and ill-defined real-world problems. This study focuses on non-engineering students' activity and perception through the assistive technology design project. For this purpose, participants engaged in a team-based technology design project. Then, a qualitative research approach was adopted, which included reflective journals with 24 undergraduate students majored in Adaptive Physical Education. The analysis identified six factors (knowledge value, social value, reality value, accomplishment value, perspective value, benefit value) of perception and five stages (topic selection, function suggestion, visualization, presentation preparation, and presentation) of activity.

• 유통과학연구
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• 제14권2호
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• pp.113-121
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• 2016

Purpose - The purpose of this study is to identify team commitment affecting employees' innovative activities and factors affecting team commitment including empowerment by leaders and job enrichment factors. In other words, so as to explain outcome variables of innovative activities, this study aims to emphasize employees' attachment roles towards their groups within nomological network, and identify the motives encouraging employees' innovative activities. The research purpose is significant due to the realistic situation of hotel industry. The reason why innovative activities are important can be found in recent changes of business environment. Also, unlike other various studies on precedence factors encouraging employees' innovative activities, this study classified those precedence factors into job and leader characteristics, and it emphasized the importance of team commitment as the process that job and leader characteristics are connected to innovative activities. Research design, data and methodology - The survey for this study was conducted during October 6^th ~ November 10^th in 2014 to the employees who are working in 5-star hotels in Korea. As for the selection of hotels and sampling method, convenience sampling method was used to the employees in 5-star hotels. Self-report method was used in the survey, judging that the employees' characteristics would be relatively homogeneous. 311 questionnaires were distributed in total, and 275 reponses were collected. After excluding the missing and unreliable responses, 245 questionnaires were used in the research. SPSS and AMOS programs were used for the analysis. Results - First, empowering leadership had positive effects on hotel employees' team commitment. It indicates that hotel employees are more committed to their team when their leaders set examples, provide information, and involve employees in decision-making process. Second, as a result of the relationship analysis in task diversity, task significance, task identity and team commitment, task diversity and task significance had significant effect on team commitment, while task identity had no significant effect on team commitment. It indicates that team commitment is enhanced when the employees can conduct diverse types of jobs and get more opportunities to talk with the guests. Also, the repetition for the same jobs in hotel rooms and the space for preparing food and beverage do not lead to team commitment, even though the employees fulfill their duties to the end. Third, hotel employees' team commitment has positive effect on their innovative activities. It indicates that employees voluntarily conduct innovative activities when they are attached to their team and identifies themselves with the team. Conclusions - There are theoretical and practical implications in this study. First, in terms of the theoretical perspective, this study proposes structural framework in team commitment, and it identifies the psychological mechanism in team commitment from the aspect of social exchange, which resulted in identification of precedence factors related to team commitment. In addition, this study presents new possibilities for relevant studies about team commitment by examining the effect on team commitment when the importance of innovative activities is emphasized in recent business environment.

• Asian Journal of Innovation and Policy
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• 제12권2호
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• pp.261-267
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• 2023

In the paper of 'Natural Selection Favors AIs over Humans,' Dan Hendrycks applies principles of Darwinian evolution to forecast potential trajectories of AI development. He proposes that competitive pressures within corporate and military realms could lead to AI replacing human roles and exhibiting self-interested behaviors. However, such claims carry the risk of oversimplifying the complex issues of competition and natural selection without clear criteria for judging whether AI is selfish or altruistic, necessitating a more in-depth analysis and critique. Other studies, such as ''The Threat of AI and Our Response: The AI Charter of Ethics in South Korea,' offer diverse opinions on the natural selection of artificial intelligence, examining major threats that may arise from AI, including AI's value judgment and malicious use, and emphasizing the need for immediate discussions on social solutions. Such contemplation is not merely a technical issue but also significant from an ethical standpoint, requiring thoughtful consideration of how the development of AI harmonizes with human welfare and values. It is also essential to emphasize the importance of cooperation between artificial intelligence and humans. Hendrycks's work, while speculative, is supported by historical observations of inevitable evolution given the right conditions, and it prompts deep contemplation of these issues, setting the stage for future research focused on AI safety, regulation, and ethical considerations.

• 정보관리연구
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• 제39권3호
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• pp.1-21
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• 2008

이 논문에서는 디지털 포맷의 기본 유형을 정의하였고, 미국의 NISO와 LC, 그리고 덴마크의 국가 및 대학 도서관/왕립 도서관의 디지털 포맷 선정 기준의 사례를 소개하였다. 이를 분석 및 종합하여 5가지 유지관리 측면의 선정 요인(설명성, 독립성, 일관성, 범용성, 품질)과 품질 및 기능성 선정 요인을 얻었다. 이를 기반으로 도서관을 위한 디지털 정보자원에 대한 포맷 선정 전략을 제시하였다.

• 산업공학
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• 제16권spc호
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• pp.1-6
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• 2003

This study deals with the problem of selecting 6 sigma projects. Traditionally, such selection was based on CTQ (critical to quality) or COPQ (cost of poor quality) derived within business units. Since the objective of 6 sigma is to achieve business goals in a short period, 6 sigma projects should be selected and carried out in coincidence with the whole company's strategies. This paper proposes two methods of selecting 6 sigma projects: one is to identify CTQ's by analyzing the company's BSC's (balanced score card) and then deploying them into subunits of the company and the other is to identify those projects with large hidden COPQ or cost of waste by applying value stream analysis and process model simulation to derive process cost models.

• Membrane and Water Treatment
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• 제11권4호
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• pp.247-255
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• 2020

Sand filter is a key unit process for particle removal in water purification treatments. Its long-standing use is due to on-site customized retrofit. Proper selection of filter media is one of the retrofit approaches to improve filter performance. This study described a series of controlled laboratory column tests and examined the effects of media property on filtration and backwash. When sand media of 0.51 mm in effective size was replaced by sand of 0.60 mm, the filter run increased up to 5 times in the given bed depth. The change of media property required an increase of backwash rate by 0.05 m/min to satisfy the requirement of bed expansion, more than 20%. When the anthracite was changed with lower effective size and uniformity coefficient, correlation with sand in the filter bed could be satisfied within the permissible error between media and bulk characteristics. Besides, this selection resulted in a well-stratified configuration of media layers after bed expansion. The column study showed that the correlation of property between the dual media had a significant effect on the filter productivity and backwash interval.