• Journal of Korean Society of Industrial and Systems Engineering
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• v.29 no.3
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• pp.135-142
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• 2006

Engineers are always concerned with life cycle costs for making important economic decisions through engineering action like reliability of products. Decisions during the reliability growth development of products involve trade-offs between invested costs and its returns. In order to find minimal LCC containing the reliability improvement cost, production cost, repair and replacement costs, and holding cost of spare parts for failure items we suggest in this paper relationship between development cost and sustaining cost in values of growth parameter $\beta$ of AMSAA model. This model is applied to the reliability growth program based on AMSAA model during R&D phase, the warranty activities of items and the block replacement policy for maintenance of items in avionic equipment.

• Journal of the Korean Statistical Society
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• v.29 no.2
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• pp.219-229
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• 2000

Oh et al.(1999) 3$\times$2 crossover design for assessing bioequivalence when two new generic drug formulations and innovator are simultaneously considered. This design is not only more efficient than 3$\times$3 one, proposed by Lee et al.(1998), in practical sense, but also more ethical in medical sense. However, the general statistical methods are not directly applicable to both designs when subjects are dropped out in the experiment, even though it is always possible in bioavailability and bioequivalence studies because of some administrative and economic reasons. In this research we propose an inference to drug effects when subjects are dropped out in the planed-for 3$\times$3 and 3$\times$2 crossover experiments. An example is given for illustration.

• Journal of the Korea Safety Management & Science
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• v.12 no.4
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• pp.191-198
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• 2010

This paper selects length of berth, area of yard, unloading capacity and number of berth as the input indexes, and cargo turnover as output index to research the source of turnover growth of 22 main ports in Korea. We gains the following results: in general, the trade ports in Korea are the stage of expansion period, the sources of turnover growth depends on the growth of factor inputs and could not be supported by TFP and technical progress. Especially in the west and east coast, TFP and technical progress is the block to the turnover growth. Four major factors to the increase of TFP are following: competition between ports, reform of property system, harbor-hinterland economic and international trade, modeling, imitation and innovation in management, technology and system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.35-36
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• 2018

Korea has many problems due to the asphalt pavement or impermeable pavement. Many methods are being implemented to improve water circulation. Among them, permeable packaging materials are used. However, existing permeable packaging materials have a problem of causing efflorescence and clogging the pores. The pores of the permeable packing material are clogged and the permeability is lost. This leads to economic problems and product problems. The purpose of this study was to develop a block to prevent efflorescence.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.1
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• pp.42-50
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• 2014

Lifting lugs are frequently used in shipyard to transportate and turn over blocks. As the shipbuilding technology develops, blocks has become bigger and bigger, and block management technology takes a more important role in shipbuilding to enhance the productivity. For the sake of economic as well as safe design of lug structure, more rigorous analysis is needed. In this study in order to investigate the strength characteristics of two type of lug, that is, D and T type lugs, non-linear strength analysis has been carried out to compare the ultimate strength characteristics of two types of lug varying in-plane and out-of-plane loading directions. Based on the present numerical analysis results, it can be drawn that T type lug is superior to D type lug from view points of ultimate strength and deformation.

• International Journal of Railway
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• v.6 no.4
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• pp.139-147
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• 2013

TSR (Trans-Siberian Railway) route is losing price competitiveness versus Deep Sea route in the transportation from East Asia to Europe, including Moscow. To further attracting the containers to the TSR route, it will be necessary (1) to keep competitive through rate, linked to fluctuating Deep Sea rate; (2) to strengthen speed advantage; (3) to enforce seamless transportation system, including simplified customs clearance procedures. In transportation to Central Asia from East Asia (Korea and Japan), TSR is competitive versus TCR (Trans-China Railway), depending on destinations. Korea has been the leader in revitalizing the TSR route since 2000. Key contributors were affluent export containers to Russia and Central Asia, port of Busan, efficient maritime transport network to Far East Russia, and Korean forwarders' persistent efforts for activating the market. Korea and Japan have a possibility of cooperation in using the TSR route efficiently, such as organizing a joint block train to a same destination.

• Proceedings of the KSR Conference
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• 2002.10a
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• pp.633-641
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• 2002

Wooden-sleeper, which has been adopted as railway turnout in Korea, has created many problems such as short life span and increase of maintenance cost. Especially turnout on Maintenance Free slab track, which has been used in city metro, has been constructed with wooden sleeper buried in concrete roadbed due to complexity of structure. However, such problem as rapid erosion in subground makes it difficult to maintain the sleeper because of frequent replacement required. Therefore, the objective of this paper is to introduce design and construction of reinforced concrete(R.C) sleeper for turnout on the concrete roadbed to facilitate maintainability and economic construction of turnout.

• Journal of Families and Better Life
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• v.20 no.6
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• pp.69-79
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• 2002

The deteriorated apartments make a social problem in now a days. After all, a new alternative plan for deteriorated apartments such as the remodelling concept must be considered. This study aims to survey the perception levels among residents in deteriorated apartments relating to remodelling. It might be provide the basic data which could be used for the analysis of consumers in the future implementation of deteriorated remodelling projects. The analytical methods adopted in this study were factor analysis, 1-test, one-way ANOVA, post-hoc estimation(Scheffe test) by the SPSS 10.1 for Windows program. Through the factor analysis for the perception types regarding remodelling, the factors were named ‘function improvement orientation’ , ‘property value orientation’, ‘individual-household improvement orientation’, and ‘negative attitude to remodelling’. The analysis of the perception types regarding remodelling, by the family characteristics, socio-economic characteristics, residence characteristics, apartment block variables, resident's value orientation, and resident's satisfaction level, indicated that the perception degree of the ‘property value orientation’was the highest, followed by the ‘function improvement orientation’.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.443-445
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• 2008

Determination of allowable overtopping rate for coastal structure is a key point to determine the application of background of coastal structure while considering safety and economic efficiency. Thus, the accurate estimation of overtopping rate against coastal structure is essential. In general, estimation of overtopping against the coastal structure is based on an empirical formula or hydraulic experiment. In this study, we investigate the behavior of overtopping for rubble mound coastal structure with rubble armor stone and wave dissipating block using hydraulics experiment, and domestic or foreign design standard.

• Proceedings of the KSEEG Conference
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• 2003.04a
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• pp.194-195
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• 2003

High-pressure amphibolite-facies rocks with serpentinized ultramafic rocks occur in the Gyeonggi Massif. Ultramafic rocks occur as lenses within Precambrian granite gneiss, which showing dominantly tectonic lines of NNE directions as well as east extensional area of the chinese collision belt between south and north China block(\ulcorner). This study regionally makes a comparative study of ultramafic rocks in the western part of the Gyeonggi Massif in Korea. (omitted)