• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.6
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• pp.987-994
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• 2016

In this paper, we present a comparative analysis of surface-mounted permanent magnet synchronous motors (SPMSM) and interior permanent magnet synchronous motors (IPMSM). First, we use 2D finite element analysis (FEA) to analyze models satisfying the same rated conditions according to the torque-speed curve characteristics, which are determined from the operating conditions. Next, we manufacture an SPMSM and IPMSM having good performances from an electromagnetic perspective based on analysis results, namely the cogging torque, torque ripple, and efficiency. We analyze both of the manufactured machines when they are connected back-to-back and when they are used as a motor and a generator, respectively. The motor is driven by a commercial inverter and the generator is connected to a three-phase resistance load bank. Finally, based on experimental results, which include the total harmonic distortion (THD) of the back electro-motive force (EMF), cogging torque, efficiency, and mass, we determine the motor that is most suitable under requirements.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.12
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• pp.1679-1685
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• 2015

This paper examines the effect of the magnetization pattern on the partial demagnetization of a permanent magnet (PM) machine that uses a ferrite magnet. Although the use of halbach-magnetized PM (HMPM) arrays in PM machines has been dramatically increasing because of their attractive features, the demagnetization characteristics of HMPM arrays have not yet been examined. In this study, two analyses of the demagnetization characteristics of HMPM arrays and parallel magnetized PMs (PMPMs) are performed, with the demagnetization characteristics being analyzed using a finite element method. According to our results, partial demagnetization occurred dramatically in the HMPM arrays. Thus, it is important to consider the vulnerability of HMPM arrays when designing PM machines.

• Journal of Digital Convergence
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• v.13 no.12
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• pp.117-124
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• 2015

As the acceptance of statistical analysis has been increased because of Big Data, the needs for an advanced second generation of statistical analysis method like Structural Equation Model are also increasing. This study suggests how R-Program, as open software, can be utilized when Partial Least Square Model, one of the SEMs, is applied to statistical analysis. R is a free software as a part of GNU projects as well as a powerful and useful tool for statistical analysis including Big Data. The study utilized R and SmartPLS, a representative statistical package of PLS-SEM, and analyzed internal consistency reliability, convergent validity, and discriminant validity of the measurement model. The study also analyzed path coefficients and moderator effects of the structural model and compared the results, respectively. The results indicated that R showed the same results with SmartPLS on the measurement model and the structural model. Therefore, the study confirmed that R could be a powerful tool that is alternative to a commercial statistical package in the future.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.06a
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• pp.252-253
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• 2012

This paper reviews achievements of logistics warehousing industry in terms of sustainable management. The introduction part of the study discusses the theoretical definitions of sustainable management and sustainable development; later part is a case study on sustainable management of in the industry. Also, this paper includes an empirical study on the influence of sustainable management activities on the customer satisfaction and corporate trust through questionnaire survey.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.10
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• pp.2331-2336
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• 2010

As basic data about students' career education in high school are being managed only in forms of NEIS, which is supported by Ministry of Education, Science and Technology, and the information for career education that homeroom teachers have operated by off-line system, it is hard to use them as practical decision support system for students' career education. In this study, we intend to design and embody web-based Student Management Total System by constructing DB of students' e-portfolios, school records and counselling data etc. As a result, teachers can carry out vocational education that is considered students' talents and aptitude, and we have a goal for promoting the growth of the students as the national human resources who have sound occupational consciousness through this education.

• Progress in Superconductivity
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• v.8 no.1
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• pp.113-118
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• 2006

The design of superconducting magnets for a 600 kJ SEMS was discussed. The basic constraint conditions in the design of a 600 kJ SMES magnet were V-I loss(<1 W), inductance of magnet(<24 H), the number of Double Pancake Coils(DPC about 10), the number of turns of DPC(<300), outer diameter of DPC(close to 800 mm) and total length of HTS wire in a DPC(<500 m). As a result of optimum design, we obtained design parameters of the 600 kJ SMES magnet with two operating currents, 360 A and 370 A, which are in the limited conditions without V-I loss. V-I loss of each operating current was calculated with design parameters and V-I characteristic of the HTS wire. As a result of calculations, V-I losses with operating currents of 360 A and 370 A were 0.6 W and 1.86 W, respectively. Even though all design parameters of the SMES magnet in case of operating current of 360 A were in the restricted conditions, V-I loss of SMES magnet showed a tendency to generate at local DPCs, which are located on the top and the bottom of the SMES magnet more than that of the other DPCs.

• Journal of the Korea Convergence Society
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• v.8 no.3
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• pp.205-214
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• 2017

The purpose of this study is to identify the perceptions of organizational members in new product development. This study suggested the successful new product development through the awareness among CEO and other members of the recognition of various factors that appear in the process of new product development by technical-oriented venture companies. Other members were more competitive in the technical area than CEO and were recognized as important strategic factors. As perceived market environment, perception of macro-environment is perceived by other members to be sensitive technical environment and economic factors, and law part is recognized as important. Recognition in a micro-environment has been associated with higher perceptions of employees and competitors, and siliar perceptions of marketing strategy and supplier relationships. This study suggested strategies for successful new product development by reducing the difference of perception between communication and environment of new products by SEMs and venture companies.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.4
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• pp.472-483
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• 2000

Before impression making in the fixed restorations or other prosthesis, hemostatic solutions are used for hemostasis and moisture control. Hemostatic solutions effectively control bleeding but their major ingredients, acid removes smear layers which are formed in the tooth preparation, exposes the dentinal tubular orifices which are occluded by smear layers, makes dentinal tubular fluid displace more easily to the various external stimulus, and according to the hydrodynamic theory, consequently causes dentin hypersensitivity. To know the effect of hemostatic solutions on dentin permeability, coronal dentin discs, 1mm in thickness, were prepared from extracted third molars free from decay and wear, and a split chamber device was used. Hydraulic conductance values and SEMs, which were measured before and after treatment with $Astringedentr^{(R)},\;Altract^(R)\;and\;Epri-dent^{(R)}$, were compared and ana-lysed. The following conclusions were drawn: 1. Hydraulic conductance values which were measured after the treatment of hemostatic solutions were increased in all groups(p<0.05). 2. %change values of hydraulic conductance were compared but no significant difference was found among the three hemostatic solutions(p<0.05). 3. On SEM observations of all groups, after treatment smear layers were removed and dentinal tubular orifices were partially exposed. On the basis of these conclusions, the reckless use of hemostatic solutions should be restricted, and when in use, various methods should be considered to protect dentin.

• Korean Institute of Interior Design Journal
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• v.21 no.3
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• pp.31-39
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• 2012

This is the time we need differentiated strategy due to consumer's standard of purchasing is becoming more complicated and corporate marketing war is intensely competitive. For a long-term strategy, making competitive corporate image is important because companies have their own competitiveness. In addition, importance of having a relationship with customer is magnified through consumers'direct and indirect experience. "The corporate complex cultural space is designed place for experiential marketing to convey its meaning to consumers." Under above concept, this study analyzed the theory of experiential marketing and conducted a survey which is based on experiential marketing strategic module (SEMs) using the analyzed theory. This study drew expression characteristics of space through case analysis and conducted a survey to have more effective corporate complex cultural space. As a result, the experience in the space enables people to understand of the space through five senses, not consist of simply chucks of sense-date, and this result emphasizes the importance of 'Event' because people tend to escape from restriction for reality to relive stress and have emotional satisfaction. In addition, it shows expression characteristics which provide sympathy as a flexible interaction through symbolical image. The result of the expression characteristics' survey is showed up to improve effect of corporate complex cultural space. This study is analyzing the corporate complex cultural space through experience marketing for the company which wants provide differentiated experience of various space expression methods and catching current position. Also, this study places its significance to give a way to increase space preference and effect of corporate complex cultural space. Based on the result of this study, I hope the future corporate complex cultural space will develop refreshingly.

• Journal of Environmental Science International
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• v.28 no.4
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• pp.455-464
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• 2019

BAT-AEL(Best Available Techniques Associate Emission Level) is the basis for establishing permissible emission standards for the workplace. Therefore, it is necessary to formulate a regulated BAT-AEL setting methodology that is generally applicable to all relevant industries. For the BAT-AEL settings, various factors should be considered such as the pollutants item, whether the workplace is subject to integrated pollution prevention and control, whether BAT is applicable, the basic data type, the emission classification system, and the suitability of the collected data. Among these factors, it is the most important factor to establish the classification system for the emitting facilities such that the emission characteristics of an industrial facility and its pollutants can be effectively reflected. Furthermore the target of the survey workplace should adhere to the BAT guidelines, even if it is a workplace that is subject to an the integrated environmental system. Certified data (SEMS, TMS, cleanSYS, WEMS, etc.) can be used to prioritize the classification system for the emission facility and the emission levels of pollutants. However, the self-measured data, daily logs, and questionnaire data from the workplace can also be used upon agreement of the relevant TWG. The collected data should only be used only when the facility is operating normally. Data that have been determined to be outliers or inappropriate validation methods should also be excluded. The BAT-AEL can be establish by adhering to the following procedure: 1) investigate all relevant workplaces with in the industry, 2)select workplaces for integrated management, 3)Identify BAT application, 4)identify whether BAT is generally applicable, 5)establish a classification system for emitting facilities, 6)collection available data, 7)verify conformity, 8)remove of outliers, 9)prepare the BAT-AEL draft, 10)deliberate, and 11) perform the confirmation procedure.