• Journal of Advanced Marine Engineering and Technology
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• v.37 no.7
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• pp.694-700
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• 2013

The design of the exhaust manifold for the pulse converters of a 4 strokes high power medium-speed diesel engine is presented in terms of fatigue analysis. The said system undergoes thermal expansion due to high temperature of exhaust gas and is exposed to intrinsic vibration of the internal combustion engine. Moreover, the exhaust pulse generates pressure pulsating along the runner inside manifold. Under such circumstances, the design and construction of exhaust manifold must be carried out in a way to prevent early failure due to fracture. To validate the design concept, a test rig was developed to simulate the combination of thermal and vibrational movements, simultaneously. Experimental results showed that a certain sense of reliability can be achieved by considering a field factor obtained from the results of engine bench tests.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.3
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• pp.110-118
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• 1995

The filling phase analysis of the injection molding process for thermoplastics was applied to predict pressure, themperature and shear stress in the test mold, and the results were compared with the experiment using 30% glass fiber added ABS resin. The finite difference method was used in the analysis considering the effects of heat transfer between molten polymer and mold wall, and also frictional heating by shear flow. The analysis results were considered as a method to improve the quality and the productivity of injection molding process. Using the analysis results, the molding factors such as mold-ability of polymers, performance of injection molding machine, positioning of gate and dimendsioning of runner in the injection molding process can be estimated at the design stage of mold for good quality and productivity.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.121-124
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• 1995

This study is aimed at cutting down the cost, weight and improving process by replacing the traditional sintered piston of the shock absorber with engineering plastic piston by means of injection molding. To obtain the high mechanical properties, glass fiber material was selected adequately and forming analysis considering fiber orientation was made to remove the forming deficit fators and to construct the optimal runner system. In addition, structural analysis using commercial software MOLDFLOW was performed under near conditions in actual driving of automotive. The results from the internal pressure process test, oilproof test based on forming, structural and strength analysis shows that hydraulic close performance and damping force considering the out of roundness of shock absorber are relatively good.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1998.04a
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• pp.250-254
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• 1998

Pump-storage power plants, which pumps water from the lower reservoir to the upper reservoir using the extra electronic power at night and generates the electronic power in the daytime, are more increasing. Currently it has a tendency to be high-head large-capacity machines. So in the processing of design, we need to know the vibration characteristics of pump-turbine shaft system sufficiently. In this paper, we developed the computer programs for analyzing pump-turbine shaft system considering magnetic force of generator, hydraulic force at runner, dynamic characteristics of guide bearings and the effect of add mass of water. And the superiority of this program was verified by applying it to the real model and calculating high quality critical speed, natural mode and unbalance response.

• Tribology and Lubricants
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• v.22 no.4
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• pp.173-181
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• 2006

In the present study, we developed a numerical analysis software to predict performance of tilting-pad thrust bearings. The finite element method was adopted to compute lubricant film pressure and temperature. Three-dimensional heat transfer equations were solved simultaneously for the lubricant film, pad, and runner. Groove temperature was assumed with two different models. From application of the software to a thrust bearing, it has been seen that the three-dimensional analysis predicts higher temperature than the average temperature analysis. It has also been found that the groove model with a hot-oil-carry-over factor predicts higher temperature.

• Design & Manufacturing
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• v.8 no.2
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• pp.50-55
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• 2014

Recently, semi-stack mold have been developed for satisfying the various elements required in the mold industry. The mold is possible using with general-purpose injection molding machine by weight reduction through the improvement of the mold structure. In order to do that, tension core, spiral cooling system and half runner system were applied. It is effective for increased productivity and decreased of loss to the materials. However, the mold is required the filling balance in order to improve the quality and efficiency. Thus this study performed that optimum design and analysis of semi-stack mold for filling balance.

• Journal of Electrical Engineering and Technology
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• v.9 no.6
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• pp.2162-2167
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• 2014

Robots are widely used in various automation processes in industrial applications. Traditionally, it operated under fixed condition by teaching operating positions. Recently, diverse 2D/3D sensors are used together with robot to give more flexibility in operation. In this paper, we deal with automatic manipulation of tie rod in automotive production line. Sensor system consisted of a camera and slit laser is used for the acquisition of 3D information and it is used attached on the robot. Nut runner is used for the manipulation of stop nut and adjust bolt on the tie rod. Detailed procedures for the automatic manipulation of tie rod are presented. In the presented approach, we effectively use 3D information in whole procedure such as computing distance to the tie rod, rotation angle of bolt and nut. Experimental results show the feasibility of the proposed algorithm.

• Asian Journal of Turfgrass Science
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• v.3 no.1
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• pp.16-23
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• 1989

입화(Burning)가 zoysia-82의 생육, 종자생산 및 thatch 감소에 미치는 효과를 조사한 결과는 다음과 같다. 1. 유초출현일수는 대비구(자연상태)와 유초출현 약 2개월전에 입화처리한 구가 짧았다. 2. 종자수량은 대비구가 가장 많았고 휴면직전과 유초출현직후의 입화구가 가장 적었다. 3. Thatch 축적은 대비구가 가장 깊었으며 휴면직전과 휴면 약 2개월 후 입화처리구가 가장 얇았다. 4. 근건중, runner 건중, 총 건물중은 휴면 약 2개월후 입화구가 가장 무거웠으며, 엽 및 엽경건중은 휴면직후의 입화구가 가장 무거웠으나 근건중 이외의 형질들은 입화처리간 유의차가 없었다. 5. Zoysia-82의 유초출현일수의 단축과 종자수량의 증가및 thatch 감소를 위해서는 유초출현 약 2개월전과 휴면 약 2개월후가 입화적기라 사료된다.

• 전기의세계
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• v.13 no.3
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• pp.28-37
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• 1964

It is the intention of this thesis to discriminate and investigate the cause of the shaft vibration of the vertical type hydroelectric power generator with respect to electrical, mechanical and hydraulic aspects, and to analyze the vibration which will occure by the each cause investigated above. In order to test the shaft vibration of No.1 generator in Hwachon, Korea new measurement method and measuring equipments were designed. In practice the shaft vibration of the generator was measured by above equipments and analyzed by the discriminative method. Detailed explanation for the designed measurement method and instruments is presented, and the results which I had tested three times for the generator No.1 in Hwachon power plant are added. As a appendix the mechanism and causes of the thrust bearing's wear and remarks for the runner are written.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.05a
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• pp.101-104
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• 2004

The application of rubber produt is a quite extensive field and has several problems in point of mass-production. The inhibitive factors at the general rubber mold are occurrence of flash, loss of raw material by curing for sprue and runner, environmental pollution by scrap junked after extraction of product and the unavailable mold structure for automation. The existence of flash at the rubber mold requires extra-process for removing or finishing it. As the reason, we can't help avoiding deterioration of quality and rising of cost. Hence we promptly need to research fur the efficient structure of mold and the preventive transforming technique of the flash without any loss of raw material in advance. This monograph is a study for Wasteless rubber mold that give us a solution for several problems happened at the general rubber mold.