• Journal of Welding and Joining
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• v.30 no.6
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• pp.120-125
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• 2012

Because ships and offshore structures have very large dimensions and complicated shapes, it is difficult to determine the deformation or internal stress in the structure by simple lab tests. Thus, a rigorous analysis by using the computer simulation technology is essential for obtaining their distortions by considering the entire production process characteristics. The rapid development of computer technology made it possible to analyze the heat transfer phenomena, deformation and phase transformation in the welded joint. For large shell structures, shell elements modeling contributed primarily to this development. But if a welding is done by multi-pass, shell elements whose thickness are unchangeable can hard to describe the local situation. Recently, it was researched how to introduce the imaginary temperature for V grooved multi-layer butt welding in strain-boundary method (a kind of shrinkage methodologies). In the present study, we formulated the imaginary temperature for the double bevel and double V groove by considering the thickness change of each pass through the bead and the thickness directions simultaneously and also demonstrated the feasibility of the formula by applying it to the thermal distortion analysis of the erection process of crane pedestal.

• Computational Structural Engineering
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• v.5 no.4
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• pp.133-142
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• 1992

An analytical model was developed for predicting the pullout behavior of straight beam longitudinal bars anchored at exterior beam-column connections. The model incorporates a local bond constitutive simulation capable of considering the effects of anchored bar diameter, yield strength and the spacing, concrete compressive strength, and column pressure on the bond characteristics of deformed bars in confined conditions of exterior joints. The analytical techniques adopted in this study were shown to satisfactorily predict the results of pullout tests on straight bars embedded in confined concrete specimens. An evaluation of the ACI-ASCE Committee 352 development length requirements in exterior joint conditions was made using the developed analytical approach. The results of this analytical evaluation are indicative of the conservatism of the current development length requirements in the confined conditions of exterior joints.

• Journal of Agricultural Extension & Community Development
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• v.18 no.2
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• pp.315-333
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• 2011

Korea and China have a similar agricultural background and they have an analogical culture and custom of food. In addition, they are located close. Thus, their agricultural sectors easily have effected each other. The purpose of this study is to review the history and situation of Chinese agribusiness, to analyze the status of Chinese investing policy which is varied after China joining in WTO, and to suggest the ways that Korean companies can successfully invest in the Chinese agribusiness sector. In addition, we explore the cases that foreign companies in Hongkong invest in the Chinese agribusiness sector. Korean companies must have a special knowledge about Chinese laws and custom of business. They also have to make a good partners who help their business. Second, before Korean companies investing in the Chinese agribusiness sector, they must carefully choice investing items. These items have to satisfy several conditions, accessing to international market as well as Chinese market and that politic assistance of Chines government is rendered. Third, when Korean companies invest in the Chinese agribusiness sector, the scale of invest would better not be large. In addition, Korean companies have to make a joint-venture company in China and build vertical integration.

• Knowledge Management Research
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• v.12 no.4
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• pp.17-40
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• 2011

This study examines the differences of enacting models and influential causes of benefit-sharing practices between Korean automobile networks and the Japanese networks. The case study method is chosen for this research because only small numbers of supply networks adopt benefit-sharing practices. I employ semi-structured interviews with managers from four automobile manufacturers and eight of their suppliers in South Korea and Japan. I find that Japanese automobile networks have adopted a higher level of trust-demanding, with a higher level of value-creating models such as supplier development, joint-new-product development. Whereas, the Korean networks have adopted the lower trust demanding, also less profitable models such as supplier's suggestion and buyer's suggestion. In terms of work-related cultural values, I find that Japanese networks emphasized collectivism. Both buyers and suppliers in the Japanese networks are supposed to have common causes. In contrast, Korean networks emphasized individualism. Both buyers and suppliers of Korea generally do not identify that they are common group members with a common cause. I also find that a slight differences of the enacting models and the causes between foreign-owned networks and domestic-owned networks within each country. Foreign-owned networks have adopted lower trust demanding, also less profitable models. The findings demonstrate that the cultural values have a decisive influence on the adoption of benefit sharing models for the networks in Japan, and South Korea.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.6
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• pp.1374-1377
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• 2008

The aim of this study is to explore the principle that the joints of the limbs belong to Five Phases in Korean medicine. According to the principle of I-Ching, Ha-Do provides the logic which could attach everything to Five Phases. Ha-Do is composed of the numbers from one through ten, and in order to explain the logic of Universe formation, it furnishes the method of transforming 'immateriality' into 'materiality'. If we apply formation theory of Ha-Do to the joints of the limbs, however, it could be understood that the trunk of body develops the appendages, which means Ha-Do suggests a logic that 'materiality' generates 'materiality' in this case. Therefore, it is not the Water but the Earth that occurs first in the appendages development in this theory, and the shoulder joints belong to the Earth. Following development should occur in order of Five Phases formation of Ha-Do ; that is to say, the elbow joints belong to the Water, the wrist joints belong to the Fire, the finger joints belong to the Wood, and the ends of fingers belong to the Metal.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.8
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• pp.1143-1150
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• 2012

This paper reviewed the general definition and role of salvage duty, and performed competency analysis based on the present state of ROK Navy's and Korean civilian's salvage operation. Also, to enhance the national salvage ability, the salvage system of advanced maritime nations such as America, Great Britain were studied. Putting these information together, it is concluded that for the expansion and development of Korean salvage system, the nationally combined salvage assets must be utilized for civilian salvage operations and internationally recognized diving certification system should be introduced and joint organization of civilian-government-Navy should be established to enable the execution of such plans.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.2
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• pp.86-93
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• 2009

Elastomeric O-rings have been the most common seals due to their excellent sealing capacity, and availability in costs and sizes. One of the critical applications of O-ring seals is solid rocket motor joint seal where the operating hot gas must be sealed during the combustion. This has long been a design issue to avoid the system failure. For laterally constrained, squeezed and pressurized condition, deformed shape of O-ring was measured by computed tomography method and CCD laser sensor, compared with numerical calculations. As clearance gap changes, sealing performance had been evaluated on peak contact stresses at top, bottom and side contact surfaces. As clearance gap increases, peak contact stresses and contact widths in top and side contact surfaces increase, and the asymmetry of stress distributions is promoted due to pressure increase. It is suggested that peak stress of bottom contact surface can be approximated by simple superposition of peak ones due to squeeze and pressure. Under pressurized condition, sealing performance is dependent on not peak stresses of bottom and side contact surfaces but that of top.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.64 no.4
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• pp.337-342
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• 2015

The company of 4 core materials that are needed for photovoltaic generation is located in area around this university in Gunsan, Saemangeum. And also, it was almost completed the value chain about the production of Polysilicon, Ingot, Wafer, modules and the design, construction of generation system. The industry-academy-government has understood that because of the relative companies' production and investment, it leads to a supply and demand of manpower and thus will have field centered manpower education. This program will help the problem of lack of manpower in relative companies by establishing competitive major agreement like vocational education system. Also, the university and the participating company in joint have pushed ahead field business education to make the least of industrial-education's mismatch, the training of professional manpower connected with related industries to make the universities chemical characteristics, companies securing excellent manpower and contributed to the revitalization of the regional economy. In this paper, are aware that photovoltaic industry is a future strategic industry for the country, so we will train the immediately site adapting manpower for the area of photovoltaic material and system as our goal. This is shown results of education operation for 4 years.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.2
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• pp.27-32
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• 2010

This paper suggests the new performance evaluation system which is suitable for high speed EFEM(Equipment Front End Module) device using a semiconductor process. An EFEM consisting of multi-joint robots is the mainstay of semiconductor automation, shuffling silicon wafers or quartz photo-masks between ultra-clean storage carriers and a variety of processing, measurement and testing systems. The theoretical and experimental studies for the development of performance evaluation system have been carried out. The presented results from the above investigation show considerably developed performance evaluation system for the high speed EFEM Especially, it is efficient for prepareing the WTO/TBT(Technical Barriers to Trade) Agreement and the PL(Product Liability) law.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.8
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• pp.1098-1103
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• 2014

This study deals with the development of an electrofusion welding machine that is capable of joining plastic pipes using a recently developed electrofusion fitting. This fitting has built-in conductive plastics that are used to weld the joint together as a heating element. In order to explain the mechanism of the new machine, 1) the resistance characteristics of the heating element were explained, 2) the method of electric welding that uses the electrofusion fitting was described, and 3) the method of power supply based on controlling the firing angle was explained. A control system for an intelligent electrofusion welding machine was proposed. This system has the ability to recognize the diameter of an electrofusion fitting using a lookup-table based on the difference of resistance curves according to fitting types, and it is able to weld the fittings regardless of the ambient temperature. A new algorithm was developed to control the power of electric welding through the recognition of feature points from the resistance curve of the heating element. In order to evaluate the performance of the developed welding machine, tests involving the welding of 16 mm- and 20 mm-type fittings were carried out. Examining the welding results, we concluded that the proposed welding machine will offer high productivity and reliability in the field of electrofusion welding.