• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.351-356
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• 1997

With the aid of advanced structural engineering, the construction of infrastructures has been recently accelerating to keep up with rapid economic growth. Construction activities and operation of transportation facilities cause civil petitions associated with vibration-induced damages or nuisances. As part of the decrease of vibration induced damage, the objective of this study is to develop vibration-controlled concrete with vibration-reduced materials, which can be recycled from obsolete materials, such as aged tires, plastics and etc. Appropriate mix proportion has been used for making 10 reinforced concrete panels with vibration-reduced materials, which have been tested to investigate on vibration reduction capability, based on the time and frequency domain analysis, and vibration velocity level analysis. Vibration-reduced mixtures are latex, styrofoam, rubber powder and plastic resin, which have been determined to by reduce vibration.

• The Journal of the Korean dental association
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• v.37 no.4 s.359
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• pp.279-286
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• 1999

In patients with severely atrophic mandibular posterior area, implant placement is a problematic surgical procedure. Inferior alveolar nerve transpositioning technique offers better initial stability of implant and reduce the risk of permanent nerve damages. In this case report, the patient has bilateral atrophic mandibular posterior edentulous area. We placed 3 implants on each mandibular posterior area in conjunction with bilateral inferior alveolar nerve transpositioning to achieve sufficient bone height. The patient complained of paresthesia in lower lip and chin area and ptosis of lower lip after surgery. Neurosensory function was normal in 10 weeks after surgery.

• Structural Engineering and Mechanics
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• v.41 no.6
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• pp.791-803
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• 2012

Significant structural damages due to pounding between adjacent superstructures of multi-span reinforced concrete (RC) highway bridges have been observed in past earthquakes. Different methods have been proposed in the literature to mitigate the adverse seismic pounding effects. This paper presents an analytical investigation on the use of magnetorheological (MR) dampers in reducing seismic pounding effects of base-isolated multi-span RC highway bridges. It has been observed that MR damper can effectively reduce the seismic pounding effect. Three control strategies (passive off, passive on, and bang bang control) of MR damper have been investigated. Although all the control strategies are found to be effective, bang bang control has been observed to be the most effective.

• Korea Trade Review
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• v.45 no.2
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• pp.67-86
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• 2020

This study analyzes the buyer's remedies for defects in title under DCFR, and it is compared with those of CISG. DCFR adopts a unitary concept of 'non-performance' which is any failure and includes delayed performance and any other performance which is not conformed with the contract. In terms of defects in title, any remedies for non-performance are available under DCFR. Thus. under DCFR, the buyer is entitled to enforce specific performance of obligations, to withhold performance, to terminate for fundamental non-performance, to reduce price, to damage for loss, to require repair, or to deliver a replacement. But under CISG, whether or not defects in title constitute 'non-conformity' is not clear and the majority understands 'non-conformity' does not include title defects. Therefore, the buyer may not has rights to require repair and delivery of replacement unlike DCFR.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.500-507
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• 1997

Recently, the construction of infrastructures has been booming and accelerating to keep up with rapid economic growth. Construction activities and operation of transportation facilities cause unfavorable effects such as civil petitions associated with vibration-induced damages or nuisances. The objective of this study is to develop vibration-controlled concrete using various vibration-controlling materials , and also to investigate dynamic properties of concrete beam depending on damage level. Vibration-controlled mixtures are latex, rubber powder and plastic resin, which have been determines to by and large reduce vibration. KS F2437 has been used to figure out 1st natural frequency and dynamic flexural rigidity. Dynamic damping rations have been, computed by adopting the polynomial curvefitting method on the frequency spectrum curve, of which results have been compared and analyzed hereon

• Journal of the Korean Professional Engineers Association
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• v.45 no.1
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• pp.45-48
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• 2012

The 2011 Japan Tsunami caused tremendous damage to coastal areas. Because of their drastic propagation speed and large run-up height, nearshore tsunami can cause catastrophic damages on coastal communities within a short time. It is necessary to establish the tsunami hazard mitigation to reduce human injury housing damage. The construction of Tsunami warning system and production of hazard map are needed for minimizing damage by tsunami.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.351-353
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• 2022

There have been several nuclear accidents at home and abroad so far, and there have been major and small damages. Overseas, in order to reduce such accidents, the safety and reliability of nuclear power plant operations have been improved by introducing a technology called Configuration Management. Through basic information on Configuration Management and successful cases of introducing Configuration Management from overseas nuclear power plants, this paper checks the technical parts applicable to Korea and examines whether they can be newly applied by supplementing them for domestic nuclear power plants.

• Journal of Fashion Business
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• v.12 no.6
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• pp.1-10
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• 2008

Public interest in healthy hairs gets growing as damaged hairs are seen more frequently with the generalization of heat permanent waves. For this study, experiments have been conducted to understand the influences on the changes in physical and morphological features of wave forms and damaged hairs, by collecting virgin hairs from the women in their mid-20's, who had not experienced chemical applications, and by dividing the applications of heat perm hair treatments, PPT(for pre-treatment) and LPP(for post-treatment), into the pre-treatment, the post-treatment, the pre & post-treatment, and the non-treatment. For the wave formations, curl waves were investigated by the bare eyes using the pictures taken by a digital camera. For the comparison of physical features, the experiments of tensile strength and elongation were done and their mean values were found. For the observations of morphological features, the pictures were taken by SEM for comparison. As for the findings, regarding the curl wave shapes of hairs, the most even and elastic S curl was formed in the case of non-treatment. In the physical features, both of the tensile strength and elongation showed a decreasing tendency in line with the hair damage levels, and the case of the pre & post-treatment indicated the tendency most similar to the control group. In the morphological features of the cuticle, observed with an SEM, the pre-treatment showed the higher possibility of reducing the cuticle damages than the post-treatment did. LPP was found to play the role of protective membrane for the post-treatment, and the pre & post-treatment turned out to reduce most effectively the cuticle damages.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.1231-1236
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• 2007

Balance Shaft Module is module parts that is installed to vehicles engine to reduce noise and vibration of vehicles engine. Balance Shaft Module's performance exerts important influence on performance of engine. Therefore, must be able to warrant quality and performance of Balance Shaft Module. Existing product found and revised error at continuous process of production, and estimated failure mode in Balance Shaft Module. Previous method hard to secure product that performance is excellent, and bring a lot of damages economically. Therefore, development of inspectin system for quality inspection of parts and performance test of assembly is essential in Balance Shaft Module. In this study, represented development process of automatic dynamic inspection system to test performance and detect breakdown of Balance Shaft Module that is producing in Dongbo.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.3
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• pp.680-685
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• 2011

Nowadays, in metropolitan railroad, DC feeding system is being generally applied. In order to reduce damages of electro-chemical corrosion caused by stray current and leakage current, in DC feeding system, rail is used as negative-polarity return conductor for traction load current. However, it has problem of rail potential increase and there are no adequate measures to prevent it in domestic. In this paper, we presented fundamental theory and related standards about rail potential increase. And then, we analyzed field testing data and simulated a variety of operations by using PSCAD/EMTDC as an analysis program of power system. In addition, voltage control device is suggested to prevent accidents caused by rail potential increase.