• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.6
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• pp.94-102
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• 2007

Applications of bonded dissimilar materials such as large scale integration (LSI) packages, ceramics/metal and resin/metal bonded joints, are very increasing in various industry fields. It is very important to analyze the thermal stress and stress singularity at interface edge in LSI. In order to investigate stress singularities on the bonded interface edges and delamination of die pad and resin in the IC package. In this paper, stress singularity factors(${\Gamma}_i$) and stress intensity factors($K_i$) considering thermal stress in the IC package were analyzed by using the 2-dimensional elastic boundary element method(BEM).

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.6
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• pp.21-28
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• 2007

Injection molding process factors such as molding temperature, injection pressure, flow rate and flow velocity, must be controlled properly in filling and packing phases in the injection molding process. In this study, effects of these factors on the injection molding were investigated through the flow analysis for birefringence and refractive index for pickup lens. This paper presents the birefringence and refractive index reduced with increasing the holding pressure and also the holding pressure time. And there are interaction with birefringence and fill time in the injection process. The optimal conditions through DOE are validated by using injection molding analysis.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.2
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• pp.71-76
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• 2008

Micro end-milling is one of effective technology that is able to do ultra-precision machining while increasing the productivity and has wide application field. But selection of machining condition is very difficult because of complicated machining mechanism. Therefore this study was carried out to select working factors to get the optimum surface roughness. Machining condition are depth of cut, feed rate and spindle revolution. The result of this study showed that Surface roughness was affected, in the other of depth of cut, spindle revolution, feed rate. And this study provided an regression equation relating surface roughness to working factors through Regression Analysis and determination coefficient of regression equation had a satisfactory reliability of 79%.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.6
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• pp.1865-1874
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• 2016

This study was to identify the factors of ethical values in nursing students. The survey was conducted in two nursing colleges (n=180) using self-reported questionnaire. The data were analyzed with descriptive statistics, t-tests, ANOVA, Pearson's correlation coefficient and multiple regression analyses using SPSS/WIN 21 software. Influencing factors of ethical values were empathy(t=3.436, p=.001), teaching method except lecture(t=3.037, p=.003), and curriculum track at high school(t=2.309, p=.022). The model was statistically significant explaining 16.2% of the variance (F=11.185, p<.001). This study suggests that strategies for increasing nursing students' ethical values include reinforcing empathy, utilizing various type of teaching method except lecture in nursing ethics class, and allowing high school students applying to college of nursing regardless of their curriculum track.

• Journal of international Conference on Electrical Machines and Systems
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• v.2 no.2
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• pp.239-245
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• 2013

Modern electric controlled valves are demanded that its solenoid actuator should be smaller size, lighter weight, lower consumption power, and higher response time. For achieving these purposes, the major design factors of solenoid actuator such as magnetic flux density, coil turn numbers, plunger size, bobbin dimension, and etc. are must be optimized. In this study, for optimal design of high speed solenoid actuator for hydraulic servo valve operation, we draw up governing equations which are composed by combination of electromagnetic theories and empirical knowledge, and deduct the values of major design factors by use of them. For more increase the operating speed, voice coil are used as main armature in manufacturing of prototype actuator. And, we have proven the propriety of the governing equations and speed increasing method by experiments using the hydraulic valve assembly adopted the prototype of solenoid actuator.

• Journal of the Korean Institute of Landscape Architecture
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• v.23 no.3
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• pp.1-14
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• 1995

The aspect of visual accessibility to urban green spaces is an important factor because it contributes making pleasant environment by increasing the visual experience of nature in urban environment. But we have tried neither to consider nor to measure it. Since he concept of visual accessibility has not formally defined yet, it was operationally defined in this study. And then the model of measuring visual accessibility was suggested and verified through the case study on neighborhood parks in Seoul. The findings are as follows : 1) The concept of visual accessibility is defined as opportunity and potentiality to observe green spaces. 2) The model of measuring visual accessibility deals with not only adjacent area but also viewshed area. In adjacent area, considering factors are the area of road adjacent to green spaces and the area of exposed green spaces. In viewshed area, considering factors are the area of road located in viewshed area, the area of exposed green spaces, and the weight according to observing distance. 3) The final model of measuring visual accessibility suggested in this study is as follows.

• Journal of Information Technology Services
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• v.10 no.1
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• pp.47-64
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• 2011

In the IT(Information Technology) service, which supply the solutions related to business management and IT, network construction and application trends, the related service business are increasing according to the enlargement of project scope and the diversity of project types as the need of service customers. In this paper, I propose the significant effect factors on the network management of IT service firms. The key findings are from the analysis result about 94 IT service firms as follows. For implementation the high performance of network management in the IT service firms, the strategic elements in the process of network construction are more conceived highly than the basic element in them. Also the perspective of project objectives are considered than the nominal perspectives in the partner selection process. The competency of partner firms', the cooperation process between the partner firms', network relation operation management and network relation structure management are the significant effect factors of network management.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.6B
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• pp.631-641
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• 2011

Digital Multimedia Broadcasting (DMB) and Internet Protocol Television (IPTV) are now in commercial service, tearing down the traditional boundaries between the telecommunications and broadcasting sectors. These latest developments also hold important implications for research projects in related areas. Both telecommunications and broadcasting being fields with a strong service orientation, market demand should be the primary consideration when selecting research and development (R&D) projects in these areas. This study presents a process for selecting converged telecommunications-broadcasting technology development projects from a demand-oriented perspective, using criteria that are based on projected future demand characteristics. Aimed at increasing the efficiency of the R&D project selection process in telecommunications and broadcasting convergence, this study can point out new directions in R&D management in this field.

• Proceedings of the KIEE Conference
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• 2009.04b
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• pp.195-197
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• 2009

The role of environment-friendly and energy-efficient rail transportation is on the rise as a "sustainable transportation means" to cope with environmental changes that are major concerns around the world. Along with the environmental problems, the CO2 inhibition issue became critical for mankind to prepare global warming and high oil prices. It has come to a point where an alternate means are needed to revitalize plans including renewable energy, bicycle utilization, and prepare new solutions for decreasing number of cars within the city The personal rapid Transit(PRT) is the revolutionary future transportation means that can replace cars to deal with ever-increasing traffic congestions, vehicles, and environmental/energy problems. Expected as an efficient means, technology development has already taken place in developed countries such as U.S., England, and Germany. To meet the future demands, PRT installation around the nation's new and existing towns is being examined to produce important factors. The factors are produced for examining the availability of system requirements during design and construction practice.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.127-130
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• 2009

Recently agricultural productivity innovation projects are increasing all over the farming countries. To reform and improve the productivity of agricultural industry is important factors. This research is to do the functional Analysis for P-C-M support System Design in Agricultural Facilities. By analyzing the for P-C-M support System modules in the agricultural construction process, P-C-M support System factors are derived and defined. The result of this study would widely be used as a fundamental research guide to develop the agricultural P-C-M support System in the agricultural construction process.