• Journal of the Korean Geosynthetics Society
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• v.2 no.1
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• pp.57-68
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• 2003

Strain-softening model is developed to characterize the interface behavior of geomembrane with geotextile and geosynthetic clay liner(GCL). The model proposed in this research is calibrated by using data from direct shear tests conducted on smooth and textured geomembrane. The research is divided into two regions, pre-peak and post-peak, to take into account of strain-softening effect. Although slight difference between measured and back calculated data is observed under high normal stress, good agreements, in general, are found from back calculations. Especially, good consistency is observed in the case of low normal stress. Based on the results, it can be concluded that the proposed model can be a reasonable constitutive law to figure out the behavior of strain-softening between interfaces of geomembrane. In addition, DSC(Disturbed State Concept) model is also presented for further application in geosynthetic interfaces.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.1
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• pp.74-85
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• 2018

This study has analyzed the convective heat transfer on the deck exposed to the high-temperature impingement exhausting from a VTOL vehicle. The heat flow of the impingement on the deck is modeled by the convection heat transfer. The convective heat flux generated by the hot impinging jet is investigated by using both convective heat transfer formulation and conjugate heat transfer formulation. Computational fluid dynamics(CFD) code was used to compute the heat flux distribution. The RANS equation and the k-e turbulence model were used to analyze the thermal flow of the impinging jet. The heat flux distribution near the stagnation zone obtained by the conjugate heat transfer analysis shows more reasonable than the convective heat transfer analysis.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.508-513
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• 2006

Anchor bolt in baseplate fastenings on the slab track is an important component to conform placing and safety of fastenings. Due to the way of load transmission control of fastenings, sometimes anchor bolt has to be applied lateral load. So we have to take care for it when we design. Especially, in the case of anchor bolt which is applied loads repeatedly, we have to consider fatigue failure. If parts of machine are damaged in static loads, stress will exceed the yield strength. So parts could be transformed largely. Therefore because they are visible to the naked eyes, we can replace parts before failure. However, because fatigue failure that are invisible to the naked eyes happen unexpectedly, it's very dangerous. To make a reasonable design of anchor bolts, we will analyze them by changing diameters of anchor bolt, quality of insert, initial gap between anchor bolt and insert, the presence of insert, etc. which affect the stresses of anchor bolts. We can get the maximum and minimum amplitude of stress through the modified Goodman diagram or Smith diagram which represents limit of all strengths and stress components to the average stress. We also tried to show the way of examining the expected th life of anchor bolt briefly through considering above.

• Journal of Fisheries and Marine Sciences Education
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• v.16 no.2
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• pp.143-155
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• 2004

The aims of this study are to analysis about the contents associated with the ocean environment compared 17 special-subject textbooks to 2 common-subject textbooks, and to make some proposals for construction of contents. The results of it are as follows; 1. Only 17 books among 36 textbooks taught by the fisheries and marine high schools are contained to some contents related with ocean environment. The contents associated with the ocean environment take possession of 90%, 62% each of total pages in the textbooks, 'ocean pollution' and 'ocean environment'. 2. Of compulsory texts, namely, 'general fisheries', 'general ocean' and 'information treatment of fisheries-marine', the former 2 books are composed of 4.5%, 36.2% each relating with ocean environment. But the last one is nothing. 3. Therefore, even a little contents of ocean environment and its conservation, it is necessary to add as the reasonable rate to the characteristics of each book in 36 special-subject textbooks. 4. And also it is shown that the common-subject textbooks,'ocean science', ' earth science I' and 'earth science II', are composed of 35.7%, 10%, 16.7% each. So we'd like to recommend that the contents of ocean pollution and environmental conservation have to add more.

• Journal of Korean Society for Quality Management
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• v.44 no.1
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• pp.61-76
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• 2016

Purpose: In order to use a word as academic terminology, we must first take a look at the meaning of that word as it is commonly used and then consider whether or not the connotation of that word is suitable to be used as academic terminology. Presently, the word Pumjil(品質) is being used as academic terminology occupying an important position in the field of business administration in Korea and is usually translated into English as 'quality'. The same is true in Japan. However, as is the case with many Korean words, the meaning that the word implies has a tendency to change gradually over time. This tendency can account for the changes or additions to the meaning a word connotes. Methods: This dissertation aims to escape from such biased ideas and study the meaning of 'Pum-Jil品質' from the view of humanities and exegetics. Then the natural definition of the word as far as business administration is concerned can be considered. Results: 'Pum-Jil品質' has been used amid changes in modern times(historic texts in both Korea and China. In Korea particularly, the word was used in the royal court until comparatively modern times.), and now it is also widely used in the field of business administration. In this process of change, a notable point is that 'Pum-Jil品質', which was originally used to mean 'nature or character of a man', took on a new meaning, 'a certain quality of a thing or a good'. Conclusion: 'Pum-Jil品質' should require basic functional 'quality' of goods or services as a prerequisite. And the functional quality should meet consumers' needs, as the pledge (trust; 信賴) for quality is between suppliers and consumers. Without consumer's trust for goods, the relationship between suppliers and consumers cannot be maintained. So goods must exchange with trust, not expenses. In conclusion, we believe it is reasonable to understand 'Pum-Jil品質' based on the meaning of 'evidence or similar rating for pledge (trust)' from the view of humanities and exegetics. In conclusion, we believe it is reasonable to understand 'Pum-Jil品質' based on the meaning of 'evidence or similar rating for pledge (trust)' from the view of humanities and exegetics.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.3
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• pp.55-63
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• 2022

A modular underground arch structure using steel and concrete has been proposed as a structure that has a simple construction process and can effectively resist cross-sectional forces generated during construction and use. Structural behavior of modular underground arch was evaluated about span length less than 15m through 3D structural analysis and test. In general, 2D and 3D structural analysis methods may be applied for structural analysis such as underground arch and tunnels. However, if a 2D or 3D structural analysis method is applied to evaluate the structural safety of a modular underground arch structure, it is difficult to model for structural analysis and it may take an excessively long time to interpret. Therefore, it may not be reasonable as a structural analysis method for considering the structural safety and earth pressure in the design process of a modular underground arch structure. In addition, when a modular underground arch structure is configured for span lengths to which the predetermined cross-section is applicable, it may be reasonable to evaluate only the safety of the structure and cross-section according to the cross-section and load conditions. Therefore, in this study, a structural analysis model using frame elements was proposed for efficient structural safety evaluation. In addition, structural analysis results of the 2D structural analysis model and the simplified analysis model using frame elements were compared, and the structural safety of the modular underground arch structure for a span length of 20m was evaluated with a simplified analysis method.

• The Journal of the Korea Contents Association
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• v.18 no.7
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• pp.28-37
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• 2018

It is necessary to produce and maintain interior lighting design reasonably and actively. Based on the lighting design applicable to interior design, the purpose of this study is to take into consideration the public design of public facilities installed in neighborhood parks and thereby to suggest a module-type variable interior lighting product design for reasonable use. To achieve that, relevant studies were reviewed to find the basic concepts of a module and the best cases of interior lighting applicable to interior design. To draw a new concept of the lighting design to which the concept of a module is applied, this study suggested the design direction for practical product development and a module-type design featuring easy process, product storage, assembly, and management, analyzed the reasonable maintenance direction for the development of lighting design, and proposed a case of design development applicable to the development of a new product design. Through cognitive strategy process, the design was made. This process, as a conceptual strategy, included the step of interior environment analysis, the step of lighting maintenance, the step of variable mechanism, and the step of emotional activation. These steps were connected with formative beauty of design so as to suggest a MLD(Module Lamp Design) strategy. In this way, this study tried to connect humans' free application for a space to a module product and to apply humans' visual approach and free conceptual value to MLD cognitive strategy design process for development.

• Journal of Korean Society of Transportation
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• v.22 no.2 s.73
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• pp.131-143
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• 2004

Given a path represented by a sequence of link numbers in a graph, the vine is differentiated from the loop in a sense that any link number can be visited in the path no more than once, while more than once in the loop. The vine provides a proper idea on complicated travel patterns such as U-turn and P-turn witnessed near intersections in urban transportation networks. Application of the link label method(LLM) to the shortest Path algorithms(SPA) enables to take into account these vine travel features. This study aims at expanding the LLM to a K-th path search algorithm (KPSA), which adopts the node-based-label correcting method to find a group of K number of paths. The paths including the vine type of travels are conceptualized as drivers reasonable route choice behaviors(RRCB) based on non-repetition of the same link in the paths, and the link-label-based MPSA is proposed on the basis of the RRCB. The small-scaled network test shows that the algorithm sequence works correctly producing multiple paths satisfying the RRCB. The large-scaled network study detects the solution degeneration (SD) problem in case the number of paths (K) is not sufficient enough, and the (K-1) dimension algorithm is developed to prevent the SD from the 1st path of each link, so that it may be applied as reasonable alternative route information tool, an important requirement of which is if it can generate small number of distinct alternative paths.

• Journal of Distribution Science
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• v.12 no.2
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• pp.95-103
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• 2014

Purpose - Korea has a better geographical location than other nations in the Northeast Asian region. This means that Korea has an opportunity to become the center of international physical distribution in Northeast Asia. Korea should take advantage of this opportunity by exploring appropriate strategies to achieve this goal, assuming government willingness, with a view to capitalizing on the geographical advantage of the Korean peninsula and constructing a comprehensive physical distribution network system. If we prepare for this scenario, Korea could become the center of international physical distribution in Northeast Asia. Research design, data, and methodology - This study has the purpose of determining how shipping companies form partnerships with third-party logistics providers, and the relevant implications. The survey methods used were personal interview and a questionnaire distributed through e-mail, fax, mail, and telephone. A total of 600 questionnaires were distributed, out of which 285 were returned. Of the collected questionnaires, 10 were excluded because of insufficient content, leaving 275 to be used in the study as available valid samples. The data that was collected from these samples was analyzed using the data coating process and by employing a statistical package program. Results - Flexible policies, administration, and systems will be needed to create better business practices. In this dissertation, first and foremost, the results reveal that in order to become the center of Northeast Asian logistics, Korea must transition into a new paradigm based on the current economic and social systems that have stemmed from bureaucracy, inflexibility, chauvinism, and egalitarianism. Flexible policies, administration, and systems will be required to create better business practices. Domestic logistics corporations need to occupy a strategic logistics hub, create a logistics network, and activate value-added logistics business strategies by ensuring significant manpower and by building a logistics information system to strengthen their competitive edge, creating an improved system. Conclusions - In this dissertation, first and foremost, we point out that in order to become a center of North East Logistics, Korea should change to a new paradigm from the old one based on current economic and social systems that have stemmed from bureaucracy, inflexibility, chauvinism, and egalitarianism. More reasonable business laws, systems, and policies based on market-driven flexibility and transparency should be created. Moreover, social norms and rules should be reasonably established, to accomplish political and social security. Korea has to cultivate a culture of tolerance for foreign companies. This involves a change of paradigm for the development of the capital city and satellite cities. It will take a powerful task force or organization to plan and execute the vision that aims to meet these needs, accomplish the necessary goals, use the appropriate system effectively, and make Korea a key country in the field of Northeast Asian logistics.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.4
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• pp.15-22
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• 2003

Seismic design codes developed taking into account the strong earthquakes may result in unnecessary economical loss in the low seismic area, and the importance of the performance based design considering the soil-structure interaction is recognized for the reasonable seismic design. In this study. elastic and inelastic seismic response analyses of a single degree of freedom system on the soft soil layer were performed considering the nonlinearity of the soil for the 1 weak earthquakes scaled to the nominal peak accelerations of 0.07g and 0.11g. The seismic response analyses were performed in one step applying the earthquake motions to the bedrock, utilizing a pseudo 3-D dynamic analysis software of the soil-structure system. The study results indicated that seismic response spectra of a system assuming the rigid base or the linear soil layer does not represent the true behavior of a structure-soil system, and it is necessary to take into account the nonlinear soil-structure interaction effects and to perform the performance based seismic design for the various soil layers, having different characteristics, rather than to follow the routine design procedures specified in the design codes for the reasonable seismic design. The nonlinearity of the soft soil excited with the weak seismic motions also affected significantly on the elastic and inelastic seismic response spectra of a system due to the nonlinear soil amplification of the earthquake motions, and it was pronounced especially for the elastic response spectra.