• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.2
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• pp.120-128
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• 2016

This paper describes power generation from sea waves by using linear permanent magnet generator. A buoy is placed on the ocean surface and connected to the generator. The wave energy is carried out from the movement of a buoy. An electrical conversion system is needed between the generator and the grid. For an analysis of the power system, the modeling of the linear generator and converter system was proceeded. This paper proposes vector control method for wave power generation system using linear generator. In order to verify the proposed method, simulation and experiment performed and the results support the validity of the control scheme.

• Journal of Intelligence and Information Systems
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• v.23 no.4
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• pp.169-196
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• 2017

The fourth industrial revolution represents a revolutionary change in the business environment and its ecosystem, which is a fusion of Information Technology (IT) and other industries. In line with these recent changes, the Ministry of Employment and Labor of South Korea announced 'the Fourth Industrial Revolution Leader Training Program,' which includes five key support areas such as (1) smart manufacturing, (2) Internet of Things (IoT), (3) big data including Artificial Intelligence (AI), (4) information security, and (5) bio innovation. Based on this program, we can get a glimpse of the South Korean government's efforts and willingness to emit leading human resource with advanced IT knowledge in various fusion technology-related and newly emerging industries. On the other hand, in order to nurture excellent IT manpower in preparation for the fourth industrial revolution, the role of educational institutions capable of providing high quality IT education services is most of importance. However, these days, most IT educational institutions have had difficulties in providing customized IT education services that meet the needs of consumers (i.e., learners), without breaking away from the traditional framework of providing supplier-oriented education services. From previous studies, it has been found that the provision of customized education services centered on learners leads to high satisfaction of learners, and that higher satisfaction increases not only task performance and the possibility of business application but also learners' recommendation intention. However, since research has not yet been conducted in a comprehensive way that consider both antecedent and consequent factors of the learner's satisfaction, more empirical research on this is highly desirable. With the advent of the fourth industrial revolution, a rising interest in various convergence technologies utilizing information technology (IT) has brought with the growing realization of the important role played by IT-related education services. However, research on the role of IT education service quality in the context of IT education is relatively scarce in spite of the fact that research on general education service quality and satisfaction has been actively conducted in various contexts. In this study, therefore, the five dimensions of IT education service quality (i.e., tangibles, reliability, responsiveness, assurance, and empathy) are derived from the context of IT education, based on the SERVPERF model and related previous studies. In addition, the effects of these detailed IT education service quality factors on learners' educational satisfaction and their work application/recommendation intentions are examined. Furthermore, the moderating roles of learner position (i.e., practitioner group vs. manager group) and participation motivation (i.e., voluntary participation vs. involuntary participation) in relationships between IT education service quality factors and learners' educational satisfaction, work application intention, and recommendation intention are also investigated. In an analysis using the structural equation model (SEM) technique based on a questionnaire given to 203 participants of IT education programs in an 'M' IT educational institution in Seoul, South Korea, tangibles, reliability, and assurance were found to have a significant effect on educational satisfaction. This educational satisfaction was found to have a significant effect on both work application intention and recommendation intention. Moreover, it was discovered that learner position and participation motivation have a partial moderating impact on the relationship between IT education service quality factors and educational satisfaction. This study holds academic implications in that it is one of the first studies to apply the SERVPERF model (rather than the SERVQUAL model, which has been widely adopted by prior studies) is to demonstrate the influence of IT education service quality on learners' educational satisfaction, work application intention, and recommendation intention in an IT education environment. The results of this study are expected to provide practical guidance for IT education service providers who wish to enhance learners' educational satisfaction and service management efficiency.

• The Journal of the Korea Contents Association
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• v.19 no.1
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• pp.430-444
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• 2019

This paper investigates the relationship between psychological independence and entrepreneurial intention of college students and the importance of entrepreneurship through empirical analysis. Therefore, In June 2018. A total of 214 samples were collected from 220 collected samples. The main findings are as follows: Firstly, psychological independence has a positive (+) effect on the entrepreneurship, but it cannot make a direct impact on the entrepreneurial intention. Secondly, It is confirmed that the entrepreneuship has a significant positive effect on each of the entrepreneurial intention. Thirdly, it is confirmed that entrepreneurship has a fully mediating role in the relationship between psychological independence and entrepreneurial intention. Fourthly, It is confirmed that the higher the entrepreneurship among male students, the stronger entrepreneurial intention, but there is no sexual difference in the relationship between psychological independence and entrepreneurship, psychological independence and entrepreneurial intention. In this paper, it has been confirmed that it is important to create a preceding factor of the entrepreneurial intention like psychological independence.

• Management & Information Systems Review
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• v.30 no.1
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• pp.39-69
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• 2011

This study is conducted to clarify when a person faces an ethical dilemma in business situation, what affects on individual ethical decision-making(from ethical judgments to behavioral intention, nonethical behaviors) in the organizational context. especially, the present study examined the direct and indirect effects of love of money, individuals' perceptions of work climate, perceptions of organizational justice on their ethical judgments and behavioral intentions regarding an ethical dilemma. The subjects of the research were Pusan National University business school enrolled students(n=160). The research was substantiated through statistical analysis of credibility and validity, correlation, variance, and moderated regression analysis. The results indicated that, although perceived ethical climate dimensions did not have a direct effect on behavioral intentions, but had a direct effect on nonethical behaviors. Climates perceived as egoistic were significant moderating effects. and love of money had a direct effect on behavioral intention. Perceptions of organizational justice had a direct effect on behavioral intentions. Especially, interactional justice had a strong influence on ethical behavioral intentions than distributive justice and procedural justice. In depth discussion implications, limitations, and future research directions were supplied.

• Journal of Global Scholars of Marketing Science
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• v.15 no.2
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• pp.27-48
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• 2005

This study analyzed the structural elements of transformational leadership on hotel employees job satisfaction and organizational identification, and inquired into how moderating variables such as demographical characteristics and the features of hotels affect transformational leadership. The ultimate purpose of this study was to provide managerial implications to hotel business operators and hotel employees. The main results of this study are as follows; According to the result of factor analysis on transformational leadership and hotel employees job satisfaction, 18 variables were derived as two factors 'obliging leadership' & 'vision leadership' factor in the area of transformational leadership, and 31 variables were derived as four factors 'welfare and work environment', 'ability display and job stability', 'colleague relationship and job performance' and 'company policy' factor. Second, stepwise regression analysis on whether the type of transformational leadership at hotels has a significant effect on employees job satisfaction & organizational identification, 'vision leadership' and job satisfaction and the both 'vision leadership' & 'obliging leadership' among the types of transformational leadership appeared to have a significant effect on hotel employees organizational identification. Third, One-Way ANOVA and t-test in order to examine significant difference in the type of transformational leadership according to demographical characteristics and general characteristics, statistically significant difference was found according to income level, the current position, work experience, the type of hotel operation and the experience of job change.

• Journal of dental hygiene science
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• v.17 no.1
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• pp.46-55
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• 2017

Many people in Korea suffer from a fear of dental treatments; however, only a few studies have focused on this population. This study assessed the effectiveness of cognitive behavioral therapy (CBT) and its interventions in reducing dental anxiety, especially when administered by trained dental staff. Using case studies, the authors analyzed the content of each session and examined the process of reducing dental anxiety. First, the authors observed that the results of both dental fear scale and subjective unit of disturbance decreased significantly with changes in cognitive distortions related to dental anxiety and that rapid improvements were noted after two therapy sessions. Second, the study reported that practicing relaxation (deep-breathing) and muscle relaxation techniques; using hand signals to indicate anxiety or discomfort; establishing an empathic relationship with the therapist; making an anxiety list; and graded insensitive and exposure along with rehearsal, were effective in coping with dental anxiety and in changing negative thoughts towards the dentist. Third, a simple cognitive behavioral intervention can be effective in reducing dental anxiety. In summary, a short-term, five-session psychological intervention with CBT produced a sustained decrease in the symptoms of dental anxiety, allowing the patients to receive the required procedures. The authors discussed the study limitations and the implication of their results on future research.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.8C
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• pp.1210-1217
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• 2004

LILI-II stream cipher is an upgraded version of the LILI-128, one of candidates in NESSIE. Since the algorithm is a clock-controlled, the speed of the keystream data is degraded structurally in a clock-synchronized hardware logic design. Accordingly, this paper proposes a 4-bit parallel LFSR, where each register bit includes four variable data routines for feedback or shifting within the LFSR. furthermore, the timing of the proposed design is simulated using a Max+plus II from the ALTERA Co., the logic circuit is implemented for an FPGA device (EPF10K20RC240-3), and apply to the Lucent ASIC device (LV160C, 0.13${\mu}{\textrm}{m}$ CMOS ＆ 1.5v technology), and it could achieve a throughput of about 500 Mbps with a 0.13${\mu}{\textrm}{m}$ semiconductor for the maximum path delay below 1.8㎱. Finally, we propose the m-parallel implementation of LILI-II, throughput with 4, 8 or 16 Gbps (m=8, 16 or 32).

• Journal of the Korean Magnetics Society
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• v.26 no.2
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• pp.55-61
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• 2016

This study proposes the design algorithm of an electromagnetic linear actuator with a divided coil excitation system, such as the colenoid (COL) system, using the equivalent magnetic circuit (EMC) method. Nowadays, the clamping device is used to hold workpiece in the electrically driven chucking system and is needed to produce a huge clamping force of 40 kN like hydraulic system. The design algorithm for electromagnetic linear actuator can be obtained using the EMC method. At first, the parameter map is used to decide the slot width ratio in the initial design. Next, to make the magnetic flux density uniform at each pole, the pole width is adjusted by the pole width adjusting algorithm with EMC. When the dimensions of the electromagnetic linear actuator are decided, the clamping force is calculated to check the desired clamping force. The design results show that it can be used to hold a workpiece firmly instead of using a hydraulic cylinder in a chucking system.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.3
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• pp.205-209
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• 2017

Unlike spherical drop impact, ellipsoidal drop impact can control the bouncing height on a heated surface by significantly altering impact behavior. To scrutinize the effect of the aspect ratio (AR) of the drop on the bounce suppression, in this study, non-axisymmetric spreading behaviors are observed from two side views and characterized based on the spreading width of the drop for horizontal principal axes. In addition, the maximum spreading width is investigated for various ARs. The results show that as the AR increases, the maximum spreading width of the minor axis increases, whereas that of the major axis shows no significant variation. In the regime of high AR and high impact velocity, liquid fragmentations by three parts are observed during bouncing. These fragmentations are discussed in this work. The hydrodynamic features of ellipsoidal drop impact will help understand bouncing control on non-wetting surfaces for several applications, such as self-cleaning and spray cooling.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.12
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• pp.36-45
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• 1998

In this paper, a method of on-line PI gain-tuninng is proposed for the speed control of brushless D.C. motor by investigating the pattern of input and output without estimating parameter. Proportional gain is tuned in the process to obtain a fast speed response by supplying the maximum constant input. And integral gain is appropriately tuned in the process of proportional control so that the response may be stably converged and the overshoot may be prevented. Therefore because both control and gain-tuning are executed concurrently, additional works that estimate parameters and so on aren't required in the proposed method. In the proposed method, both fast-response and overshoot problem are well solved, and it is more useful and convenient than existing auto-tuning methods in the speed control of D.C. motor. It is illustrated by simulations and experimental results that the proposed method is useful and stable.