• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.12
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• pp.2000-2007
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• 2016

Generally, in order to implement the CRM(Critical Conduction Mode), the analog controller is used rather than a digital controller because the control is simple and uses less power. However, according to the semiconductor technology development and various user needs, digital control system based on a DSP is on the rise. Therefore, in this paper, the CRM bridgeless PFC converter based on a digital control is proposed. It is necessary to detect the inductor current when it reaches zero and peak value, for calculating the on time and off time by using the current information. However, in this paper, the on-time and off-time are calculated by using the proposed algorithm without any current information. If the switching-times are calculated through the steady-state analysis of the converter, they do not reflect transient status such as starting-up. Therefore, the calculated frequency is out of range, and the transient current is generated. In order to solve these problems, limitation method of the on-time and off-time is used, and the limitation values are varied according to the voltage reference. In addition, in steady state, depending on the switching frequency, the inductance is varied because of the resonance between the inductor and the parasitic capacitance of the switching elements. In order to solve the problem, inductance are measured depending on the switching frequency. The measured inductance are used to calculate the switching time for preventing the transient current. Simulation and experimental results are presented to verify the proposed method.

• Journal of the Korean Society of Physical Medicine
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• v.4 no.4
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• pp.257-267
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• 2009

Purpose：The purpose of this study is to examine the effectiveness of ultrasound and myofascial release in patients who have opening mouth limitation and temporomandibular disorder. Methods：Twenty students were randomly assigned to a myofascial release group(n=10) or an ultrasound group(n=7). Each group was treated for 15 minutes per a every treatment session for four weeks. Cervial range of motion(CROM) was used to measure cervical R.O.M., and a mm(millimeter) graduated ruler was used to measure opening mouth limitation. Results：Results of the follows : 1. The neck extension of range of motion of both groups was significantly increased in length of time (p<.05). 2. The neck flexion of range of motion of both groups was significantly increased (p<.05). 3. The quantity of opening mouth of temporomandibular joint of both groups was significantly increased (p<.05). Conclusion：These data suggest that myofascial release and ultrasound are beneficial to increasing a functional recovery of neck(flexion and extension) and opening mouth.

• Journal of the Korea Safety Management & Science
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• v.11 no.1
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• pp.103-113
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• 2009

Motorola which had developed and commercialized wireless telephone and mobile phone for the first time in the world made a decision on the separation of the mobile unit from the Motorola due to the continuous bad performance turn. In addition, the Korean company named Raincom which had developed and commercialized MP3 player have been disappeared since Raincom failed to compete with iPod of Apples. What is the main cause the companies that have been top of the world level weed out of IT product market? For less product life cycle and globalization of market, the company's competitiveness tends to be determined based on company's creative capability, rather than process implementation capability. Thus, companies spent a great amount of time and effort in the introduction of creativity management and R&D activities. However, as company's continuous investment on R&D and innovation activities did not lead to business performance, they starts to pay much attention on the effective R&D and innovation activities. Therefore, this paper tries to solve the limitation of the effectiveness of R&D activities by introducing the concept of 'creative quality'. The creative quality is executed by the creative process, which is designed for getting over the limitation of the traditional brainstorming method. This paper presents the concept so called 'creative quality management' and expects it to be an alternative to conquest the limitation of six sigma management.

• Journal of Arbitration Studies
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• v.27 no.2
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• pp.37-57
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• 2017

On 9 March 2017, a Tribunal constituted under the ICSID Convention issued its ruling in the case of Ansung Housing v. People's Republic of China, dismissing with prejudice all claims made by the Claimant, Ansung Housing Co., Ltd., in its Request for Arbitration, pursuant to ICSID Arbitration Rule 41(5). Ansung Housing v. PRC has drawn attention since it is the first case where an investor with Korean nationality initiated an ICSID arbitration on the basis of the Korea-China Bilateral Investment Treaty (BIT) as amended in 2007 between the Republic of Korea and the People's Republic of China. The Tribunal finds that its ruling is about a lack of jurisdiction of the ICSID and of its own competence as well as regarding manifest lack of legal merit due to a lack of temporal jurisdiction, since a Respondent's Rule 41(5) objection is concerned with the three-year limitation period in Article 9(7) of the Korea-China BIT. The Tribunal held that, under Article 9(7) of the Korea-China BIT, the limitation period begins with an investor's first knowledge of the fact that it has incurred loss or damage, not with the date on which it gains knowledge of the quantum of that loss or damage. Finally, the Tribunal held that Ansung submitted its dispute to ICSID and made its claim for purposes of Article 9(3) and (7) of the BIT after more than three years had elapsed from the date on which Ansung first acquired knowledge of loss or damage and that the claim is time-barred and, as such, is manifestly without legal merit. It remains to be seen whether the aggrieved Claimant initiates annulment proceedings before an ad hoc committee under the ICSID Convention. It is quite interesting to see whether the decisions by the Tribunal should be reversed on the basis of the Claimant's arguments as to the start date as well as the end date of the limitation period under the Korea-China BIT.

• Journal of Korean Institute of Industrial Engineers
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• v.5 no.2
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• pp.2-7
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• 1979

The fundamental stochastic duel of Williams and Ancker is combined with the probabilistic linear, square and mixed laws of Brown and Smith when the battle time is limited and interfiring times are continuous. The Probability of a given side's winnig or a draw is derived in a recursive equation with Laplace transforms. Examples with negative exponential firing times are given. In linear law an exact closed form solution is obtained, whereas for square and mixed laws only square ($2{\times}2$) duels are considered.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.10a
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• pp.331-338
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• 2004

In this paper, stiffness and damping matrices are experimentally constructed using structural modal information on frequencies, damping ratios and modal vectors, which are obtained by shaking table tests. The acceleration of the shaking table is used as the input signal, and the resulting acceleration of each floor is measured as output signal. The characteristic and limitation of modal information from shaking table test are obtained by Common Based-normalized System Identification(CBSI) technique which is based on time domain information.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.1109-1112
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• 2005

The software reliability is defined, and not only the relations between testing time and reliability, but also the relation between duration following failure fixing and reliability are studied in this paper. The release time making the testing cost to be minimum is determined through evaluating the cost for each condition. Also, the release time is determined depending on the conditions of the first reliability, considering the specified reliability. The optimum release time is determined by simultaneously studying two optimum release time issues that determine both the cost related time and the specified reliability related time. And, each condition and limitation are studied. The trend of the optimum time is also examined.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.1
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• pp.18-25
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• 2002

The software reliability is defined, and not only the relations between testing time and reliability, but also the relation between duration following failure fixing and reliability are studied in this paper. The release time making the testing cost to be minimum is determined through evaluating the cost for each condition. Also, the release time is determined depending on the conditions of the first reliability, considering the specified reliability. the optimum release time is determined by simultaneously studying two optimum release time issues that determine both the cost related time and the specified reliability related time. And, each condition and limitation are studied. The trend of the optimum time is also examined.

• Journal of Korea Multimedia Society
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• v.22 no.8
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• pp.887-896
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• 2019

In this paper, we discuss an optimization approach for time-synchronizations in networked simulators. This method is a sub-technology that is required to combine heterogeneous simulators into a single simulation. In previous time-synchronization studies, they had built a network system among networked simulators. The network system collects network packets and adds time-stamps to the networked packets based on the time that occurs in events of simulation objects in the individual simulators. Then, it sorts them in chronological order. Finally, the network system applies time-synchronization to each simulator participating in interworking sequentially. However, the previous approaches have a limitation in that other participating simulators should wait for while processing an event in a simulator in a time stamp order. In this paper, we attempt to solve the problem by optimizing time-synchronizations in networked simulation environments. In order to prove the practicality of our approach, we have conducted an experiment. Finally, we discuss the contributions of this paper.

• Journal of the Institute of Convergence Signal Processing
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• v.3 no.3
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• pp.41-46
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• 2002

We generally used electric optical sensors in order to detect and identify sea objects efficiently. However due to the limitation of view-angle, the region acquired from the sense is restricted. So it is necessary to generate panoramic image from sea images acquired from pan-tilt camera. Previous mosaicing method is not able to generate panoramic image for sea environment because intensity is similar to all region and time varying. In this paper, we proposed new algorithm for generating high-resolution panoramic image on sea environment. Proposed algorithm use single-view point model, applying mosaicing result in feature environment to in sea environment, we overcame the limitation of previous method. In the result of virtual and real experiment, we showed that proposed algorithm is efficient for generating sea panoramic image.