• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.5
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• pp.847-853
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• 2010

This paper describes switching surge analysis for reclosing decision in 345kV combined transmission line with XLPE power cable. Reclosing operation should be decided based on the detailed technical analysis in combined transmission line because this line includes power cable section which is week on insulation. Insulation of power cable can be breakdown at the week point in case of reclosing moment. Therefore the detailed analysis has to be carried out by considering several conditions such as length ratio of power cable section, arrestor, inserting resistance, charging rate, grounding resistance, etc.. On the other hand sheath voltage on IJ(Insulated Joint) is analyzed to check dangerous condition on cable cover. Analysis is performed by EMTP/ATP. Analysis results show that reclosing can be operated as the single line-to-ground fault occurs on overhead line in 345kV combined transmission line, if the inserting resistance is considered before the operation of main circuit breaker.

• Journal of Dental Rehabilitation and Applied Science
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• v.19 no.4
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• pp.317-323
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• 2003

When making crown and bridges on anterior regions, many practitioners consider the esthetics the most. For this reason functional aspect are not considered as much as the esthetics. If the occlusion on the anterior region are not formed correctly, movement of the temporomandibular joint can be disturbed and excessive stress can be occur that pathologic condition can be under lied. On this case presentation will show the importance of the anterior guidance and suggest the appropriate protocol of using customized anterior guide table. A 45years old male had to remake both of the upper central and lateral PFM because of the porcelain fracture. The new PFM crowns were made conventional methods without considering the anterior guidance. After the temporary setting, the patient complained of discomfort and short looking upper anteriors. To solve these problems we had to restore the palatal contour and length of the new crowns by making customized anterior guide table using temporary crowns that contains patient's old anterior guidance. This procedure which is copying the pt's comfortable anterior guidance to the final prosthesis made them to be esthetic and patients to feel comfortable.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.2
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• pp.267-276
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• 1993

This paper discusses the neural network application in the study on the obstacle avoidance of robot manipulator during the trajectory planning. The collision problem of two robot manipulators which are simultaneously moving in the same workspace is investigated. Instead of the traditional modeling method, this paper processing based on the calculation of joint angle in the cartesian coordinate with constrained condition shows the possibility of real time control. The problem of the falling into the local minima is cleared by the adaptive weight factor control using the temperature adding method. Computer simulations are shown for the verification.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.1
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• pp.88-94
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• 2012

An axle drive shaft with double joint shaft, cross kit and yoke has an important role by transferring power and changing steering angle between axle and wheel in power train system. It has been used widely in the heavy machinery requiring a high reliability in the power train system. At fatigue failures of the axle drive shaft with the long span, a relatively high stress concentration at a snap ring groove on the drive shaft brings to significant fatigue damages under repeated loading condition. As Peterson's suggestions on this study, a relief groove in the vicinity of the snap ring groove is applied by decreasing the stress concentration and improving the fatigue life of axle drive shaft. By using FEM analysis, the decreasing effect of the stress concentration and extended fatigue life are due to the change of design parameters related with size and location of the relief groove. The relief groove with the design parameters such as d/b=2.0 and r/h=1.2 enables to decrease the stress concentration of 22.3% and increase the fatigue life more than 3 times by comparing with no relief groove application.

• Steel and Composite Structures
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• v.8 no.6
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• pp.457-473
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• 2008

Yielding of the internal steel reinforcement is an important mechanism that influences the Intermediate Crack-induced debonding (IC debonding) behavior in FRP-strengthened RC members since the FRP is required to carry additional forces beyond the condition of steel yielding. However, rational design practice dictates an appropriate limit state is defined when steel yielding is assured prior to FRP debonding. This paper proposes a criterion which correlates the occurrence of IC debonding to the formulation of a critical steel yielding length. Once this length is exceeded the average bond stress in the FRP/concrete interface exceeds its threshold value, which proves to correlate with the average bond resistance in an FRP/concrete joint under simple shear loading. This proposed IC debonding concept is based on traditional sections analysis which is conventionally applied in design practice. Hence complex bond stress-slip analyses are avoided. Furthermore, the proposed model incorporates not only the bond properties of FRP/concrete interface but also the beam geometry, and properties of steel and FRP reinforcement in the analysis of IC debonding strength. Based upon a solid database, the validity of the proposed simple IC debonding criterion is demonstrated.

• Archives of Plastic Surgery
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• v.45 no.4
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• pp.363-366
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• 2018

Background Camptodactyly refers to permanent flexion contracture at the proximal interphalangeal joint. Most cases are limited to fifth-finger involvement. Although common, the treatment of camptodactyly is controversial. Many published studies have emphasized conservative treatment, while others have described surgical procedures. The problem with this deformity is that it presents in several forms, which means that there is no single model for effective treatment. The aim of this paper is to present the difficulties encountered with this condition and the management thereof on an individual basis. Methods This is a case series of 14 patients (nine males, five females) who underwent surgical treatment. The results were classified using the method from Mayo Clinic as excellent, good, fair, and poor. Results Fourteen patients with 15 fingers underwent surgery, and the results achieved were as follows: excellent, 0; good, 1; fair, 6; poor, 8. The treatment of camptodactyly still remains controversial, and hence proper planning individualized to each patient is needed to achieve the maximal improvement with realistic goals. Conclusions Although we performed individualised surgery, our careful follow-up was not able to identify any method as superior over another with respect to gain in extension and loss of flexion. We therefore propose that the extensor mechanism should not be disturbed during surgery to treat camptodactyly cases.

• Journal of Power System Engineering
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• v.19 no.4
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• pp.11-16
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• 2015

Welding is very popular method for joining two or more metals. In this paper, the three-way factorial design was adopted for obtaining the optimum friction stir welding conditions of Al 5052 alloy. Tools of shoulder diameter of 9, 12, 15 mm and pin length of 1.5 mm were used. Also the material's dimension for welding was $100{\times}100{\times}2mm$, and the tensile specimens were worked by water-jet technique. Welding variables were shoulder diameter, rotating speed of tool and welding speed. As far as this work is concerned, optimum condition for friction stir joint of Al 5052 alloy was predicted as the shoulder diameter of 15 mm, welding speed of 500mm/min and rotating speed of 1000 rpm. In addition, the presumed range of tensile strength under the optimal conditions is estimated to be $208.3{\pm}5.7$ MPa with 99% reliability.

• Journal of the Korean Geotechnical Society
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• v.29 no.1
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• pp.61-70
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• 2013

This paper presents the results of a two-dimensional finite element analysis of end bearing capacity of single pile installed in fractured rock mass. A number of cases were analyzed using Hoek-Brown criterion that can consider the condition of rock joints. Considering a wide range of joint conditions in which the pile is embedded into the rock, GSI was set as a main parameter. And the effects of pile diameter, unconfined compressive strength of rock and Hoek-Brown constant $m_0$ were considered. Based on parameter study, end bearing load factor graphs were suggested.

• Wind and Structures
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• v.31 no.4
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• pp.363-371
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• 2020

Proper understanding of offshore wind speed variability is of essential importance in practice, which provides useful information to a wide range of coastal and marine activities. In this paper, long-term wind speed data recorded at various offshore stations are analyzed in the framework of fractal dimension analysis. Fractal analysis is a well-established data analysis tool, which is particularly suitable to determine the complexity in time series from a quantitative point of view. The fractal dimension is estimated using the conventional box-counting method. The results suggest that the wind speed data are generally fractals, which are likely to exhibit a persistent nature. The mean fractal dimension varies from 1.31 at an offshore weather station to 1.43 at an urban station, which is mainly associated with surface roughness condition. Monthly variability of fractal dimension at offshore stations is well-defined, which often possess larger values during hotter months and lower values during winter. This is partly attributed to the effect of thermal instability. In addition, with an increase in measurement interval, the mean and minimum fractal dimension decrease, whereas the maximum and coefficient of variation increase in parallel.

• Journal of the Korea Computer Industry Society
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• v.7 no.3
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• pp.263-270
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• 2006

Magnetic nerve stimulation treatment is much backward real condition than other field. Specially, successful medical treatment introduction of magnetic field (MF) can was refered long ago in Avicenna's work, and is thought as age of medicine magnetology development recently. These development is achieved through biologist and biophysicist and clinician's joint effort, but, new mountings and relationship air tassel are developed steadily. Magnetic nerve stimulation treatment field designs treatment system by each function during long wave high-amplitude (traditional magneto therapy of greatly great that strong that) short time that CMF, VMF, PMF field etc. are representative but are HPMT technology in this research and manufacture and special quality did comparative analysis.