• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.3
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• pp.506-513
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• 1992

본 연구에서는 복합재 구조물에 대하여 유한요소해석법에 현상학적 모델인 전 단지연해석을 도입하여 강성저하와 모재파손을 예측하고 변형률을 매개변수로 한 Wei- bull 함수를 섬유파손해석에 도입하여 초기파손후의 거동을 묘사하고자 한다. 그리 고 면내전단하중이 작용하는 경우에 대해 전단지연해석을 수행할 수 있도록 모델링을 확장했다. 모재균열의 존재로 인한 단층의 강성변화는 실험으로 측정이 불가능하므 로 유한요소해석을 수행하여 비교하였다. 이 모델로부터 전단강성의 저하를 평가하 는 방법을 사용하였으며, 모재파손의 밀도 예측도 평균변형률 개념으로 전단효과를 고 려할 수 있도록 수정하였다. 그리고 초기파손후의 거동을 점진적으로 해석하기 위해 비선형 유한요소프그램을 작성하고, 상기의 모델을 도입하여 초기파손후의 거동을 보 다 정확히 묘사할 수 있는 방법을 제시하고 예로서 평시편에 대해 해석하고 실험치 및 타방법의 결과와 비교하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.1317-1319
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• 2007

최근에 광대역망을 기반으로 방송서비스를 포함하여 통방융합 서비스를 제공하는 IPTV 서비스에 대한 관심이 고조되고 있다. IPTV 서비스에 있어서 기존의 방송채널들은 킬러 애플리케이션의 하나로써 재사용되어지며 이를 위한 IPTV 미들웨어 구조에 대한 연구가 필요하다. 특히 대부분의 상용 서비스는 기존의 방송서비스에서 사용되고 있는 기술을 수정없이 사용하고자 하는 이유로 인하여 IP 환경에 비효율적인 구조를 채택하고 있다. 본 논문에서는 기존의 방송채널을 재전송함에 있어 IP 환경에 최적화 될 수 있는 기술을 제안하고자 한다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.3
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• pp.325-330
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• 2012

This paper describes the structural analysis and optimization of stiffeners used in inner tanks for liquid natural gas (LNG) storage, so that the costs can be minimized while the critical buckling load of the inner tank still exceeds the external pressure exerted by the perlite. The original calculation of perlite pressure applied to the inner tank was based on Zick's code, which led to the overestimation of the external pressure, and consequently, an oversized stiffener. In this study, the effects of the material properties of perlite on the external pressure distribution are scrutinized, and the optimum dimensions of a single stiffener are finally obtained through a series of parametric studies. A 15% decrease in the cost of the stiffener compared with the original design is achieved.

• Journal of the Korean Society for Library and Information Science
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• v.54 no.4
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• pp.147-167
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• 2020

The purpose of this study is to analyze the factors influencing the intention of revisiting and recommending by applying a structural equation model, targeting the service quality factors of university libraries derived from previous studies. For 11 days from April 30th, 2020 to May 10th, 2020, a total of 127 user groups (undergraduate students, graduate students, professors/instructors) were surveyed on their intention to revisit and recommend. The analysis results are as follows. 'Materials' and 'service customization' were shown as quality dimensions that influence revisit. In addition, revisiting was found to have an effect on recommendation intention, and it was analyzed that 'materials' and 'service customization' affect not only revisit but also recommendation intention. In addition, 'service customization' was found to be a factor that directly affects the intention to recommend. Based on this, a method of applying the concept of customization to library services and marketing was proposed in an environment where users' needs are diversifying and becoming personalized.

• Journal of Global Scholars of Marketing Science
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• v.8
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• pp.451-473
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• 2001

This research aims to investigate the structural relationship among service quality, service value, satisfaction, relation quality and re-use intention and to establish the conceptual framework for the relationship between customer and service supplier. This research employs LISREL 8.30 for an empirical approach. With consumers in beauty shops supplying intangible and autonomous-oriented services, it was found that (1) perceived service quality was positively related to service value, satisfaction, relation quality and re-use intention, (2) service value encouraged satisfaction and relation quality, (3) satisfaction and relation quality showed relationship with re-use intention while no relationship between service value and re-use intention was tested, (4) re-use intention presented relatively strong relationship with relation quality geared from interaction between customer and service supplier than with customer satisfaction. Some implications of these results are discussed. Among others, it is noted that the small and customized firms must put their attention on relationship marketing.

• Computational Structural Engineering
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• v.9 no.1
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• pp.33-45
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• 1996

A general stiffener element which includes transverse shear deformation is formulated using the p-version finite element method. Hierarchic C/sup o/-shape functions, derived from Integrals of Legendre polynomials, are used to define the assembled stiffness matrix of the stiffener with respect to the local reference frame is transformed to the plate reference system by applying the appropriate transformation matrices in order to insure compatibility of displacements at the junction of the stiffener and plate. The transformation matrices which account for the orientation and the eccentricity effects of the stiffener with respect to the plate reference axes are used to find local behavior at the junction of the stiffener and the relative contributions of the plate and stiffener to the strength of the composite system. The results obtained by the p-version finite element method are comared with the results in literatures, especially those by the h-version finite element analysis program, MICROFEAP-II.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.939-941
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• 2017

The use of composites is increasing for lightweight aerospace structures. Among these structures, the ring frame and the parts of the projectile body are mainly made of a fiber reinforced composite material which is less susceptible such as delamination to structural damage. As the use of fiber reinforced composites increases, interest in modeling efficient methods of stiffness and strength is increasing. This paper predict the mechanical strength according to the repeating unit cell(RUC) of the 2-D triaxial braided composites of fiber reinforced composites. Yarn slice definition, incremental approach and stiffness reduction model were used as strength prediction. Finally, the results of strength prediction are verified by comparing with experimental data of 2-D triaxial braided composites specimens.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.2
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• pp.90-97
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• 2018

The quantities of electronic waste have been increased rapidly, and was caused variety problems such as environmental pollution or dissipation of resource. So, it needed to development of recycling technology about heavy metal in the electronic waste. Meanwhile, filler material (concrete or mortar) was used for shielding radioactive waste, however, it did not used materials that it is proved radiation shielding performance. So, there is a lack of confidence in the shielding performance. Therefore, in this paper, mechanical properties of concrete was evaluated for the applicability using electronic waste as fine aggregate of filler material. From the test results, compressive and flexural strength and elasticity modulus and the micro pore in the $1{\mu}m$ range was significantly affected by substitution of electronic waste, however, it could be improved the performance by using mineral admixture as binder. So, it is shown that the electronic waste could be applicable as fine aggregate of filler material.

• Journal of the Society of Naval Architects of Korea
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• v.37 no.1
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• pp.99-110
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• 2000

The damages due to wave impact loads are largely affected by impact pressure impulse and impact load area. The objective of this study is, as the third step, to perform dynamic structural analysis of bow flare structure of 300,000 DWT VLCC using LS/DYNA3D code, and to verify its dynamic structural behaviors. The impact load areas of stiffener space $1.5s{\times}1.5s$ and $2.5s{\times}2.5s$ are applied to bow flare structure part with relatively flexible stiffeners, and with stiff members such as stringers, webs etc., respectively, under the wave impact load with peak height 6.5MPa, tail 1.0MPa, and duration time 5.0msec. Through the dynamic structural analysis in this study, it might be thought that the structural strength of bow flare structure is generally sufficient for these wave impact load and areas, except that large damages were found at bow flare structure area with flexible wide span stiffeners.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.579-585
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• 2017

Development of a facade system that can reduce load factor and costs in high-rise building construction is required. The proposed cable wall system is used as a structural support by the glass-cable and can increase openness on lower elevations and the lobby area. Its use in high-rise buildings can reduce construction costs. Without transferring directly a strong initial tension of the cable to the building frame is connected to the steel member and the reinforced concrete structures, by absorbing the initial tension of the cable, it is possible to control the occurrence of a strong concentrated loads to the structure. Comparison of load-displacement test results from the numerical analysis with the test results showed reasonable agreement, Therefore, the proposed numerical results confirm good prediction of cable behavior for the facade system.