• 산업경영시스템학회지
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• 제33권4호
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• pp.130-137
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• 2010

This paper analyzes the main factors affecting user selection of a small-sum electronic payment system using survey data of 396 users. Several findings emerge. First, users consider three pillars and eight factors in adopting a new system : system features(stability, security, and flexibility), transaction cost(payment commission and settlement period), and financial capability of provider(stability of financial structure, risk management capability, and funding capability). Second, the stability of the financial structure of the system provider is the most important factor to user acceptance of a new e-payment system. Users tend to consider uncertainty risk more seriously than transaction cost. This reflects the reality that electronic payment system service industry has not fully fledged yet. Third, some moderating effects exist according to payment methods and business usages. As for payment methods, speedy settlement cycle for wired/wireless phone payment, system stability for credit card and account transfer payment, and security for advance payment means are crucial factors. As for business usages, the stability of financial structure for online game content, system stability for music and video content, proxy payment commission for e-learning content, flexibility of the payment system for digital adult content, and security for public services are decisive ones.

• 터널과지하공간
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• 제20권4호
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• pp.292-298
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• 2010

본 연구는 발파진동에 의한 지반진동이 구조물에 미치는 영향을 평가하기 위함이다. 이를 위하여 지반에서 측정한 자료를 토대로 Newmark $\beta$ 방법을 이용하여 단자유도계(SDOF)를 가정한 구조물 동적응답 시간이력과 구조물에서 직접 측정한 진동 시간이력을 비교 하였다. 지반과 구조물의 측정 자료로부터 시간이력을 해석한 결과, 단일공 발파와 20 ms 단차 발파에서 지반진동과 구조물 사이의 진동 크기는 약 3배의 차이로 구조물에서 더 큰 진동을 보이는 것으로 나타났다. 구조물 동적응답 시간이력을 해석한 결과, 그 값은 구조물에서 직접 측정한 자료와 유사한 최대 진동속도를 보였으며, 이것은 구조물 하부 지반에서 측정된 지반진동 측정자료에 근거하여 구조물의 진동특성을 예측할 수 있음을 지시한다.

• 비교교육연구
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• 제27권1호
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• pp.51-76
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• 2017

본 논문은 독일통일 후 구동독지역에서 실시된 학제통합 과정에 대한 고찰을 통해 남북한 통일 후 교육통합 과정에서 고려해야 할 시사점을 도출하는데 연구의 목적이 있다. 독일 통일 전후 단계에서 구동독의 학제는 전환기 과정을 거쳐 구서독의 학제에 통합되었다. 구동독의 학제통합은 전환기 조치를 통한 안정적 관리, 동서독 간의 협의 추진, 지역별로 상이한 학제 체제의 도입, 통일 후 사회적 변화 상황에 대한 유연한 대처의 측면에서 긍정적인 특성을 가지고 있다. 반면, 단기간의 개편 추진, 구동독 학제 체제에 대한 고려 미비, 학제 통합 후 내적 인프라 구축의 어려움 등의 한계를 나타냈다. 통일독일의 학제통합 과정 사례는 남북한 통일 후 교육통합을 준비해야 하는 우리에게 학제통합의 안정적 추진을 위한 방안의 수립, 북한 학교체제에 대한 면밀한 검토, 학제통합에 따른 내적인프라 구축 방안 마련 등이 필요하다는 시사점을 제시한다.

• Wind and Structures
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• 제23권5호
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• pp.421-447
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• 2016

Wind-induced and earthquake-induced excitations on tall structures can be effectively controlled by Tuned Liquid Damper (TLD). This work presents a numerical simulation procedure to study the performance of tuned liquid tank- structure system through ${\sigma}$-transformation based fluid-structure coupled solver. For this, a 'C' based computational code is developed. Structural equations are coupled with fluid equations in order to achieve the transfer of sloshing forces to structure for damping. Structural equations are solved by fourth order Runge-Kutta method while fluid equations are solved using finite difference based sigma transformed algorithm. Code is validated with previously published results. The minimum displacement of structure is observed when the resonance condition of the coupled system is satisfied through proper tuning of TLD. Since real-time excitations are random in nature, the performance study of TLD under random excitation is also carried out in which the Bretschneider spectrum is used to generate the random input wave.

• 항공우주시스템공학회지
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• 제6권4호
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• pp.1-6
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• 2012

The morphing flap wing has different structure unliked general wing structure. The actuated chord length of the morphing flap was more longer than conventional wing flap. In this reason, morphing flap wing structure was important to bending moment by aerodynamic lift force. In this study, through the fluid-structure interaction using computational fluid dynamics and structure finite element analysis to apply that the morphing flap wing's static aeroelastic stability analysis.

• 기술사
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• 제19권2호
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• pp.21-25
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• 1986

Structure-borne noise due to forced vibration which is originated from subway operation and transmitted to buildings in order of rail-wood tie-concrete bed-structure-soil-building foundations-members of building results in social problem of environmental pollution. Moreover this becomes a serious problem because of the increment of surface traffic and subway operation made by meeting traffic system in crowded cities. Since subway is constructed along the principal road or through the residential area and as the worst case may be, building foundations is contact with top part of subway structure, it is possible that vibration resonance results in fatal damage of buildings. And, structure-borne vibration noise due to subway operation at late and early hours have the residents suffer from insonmia, restlessness and so on. Therefore, to satisfy the future need concerning the environmental protection, this report deals with the influence of structure-borne vibration noise on the basis of the characteristics of Seoul Subway System.

• Smart Structures and Systems
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• 제11권2호
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• pp.199-215
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• 2013

During the service life of a structure, design complications and unexpected events may induce unforeseen vibrations. These vibrations can be generated by malfunctioning machinery or machines that are modified or placed without considering the original structural design because of a change in the intended use of the structure. Significant vibrations occurred at a natural gas plant cooling structure during its operation due to cavitation effect within the hydraulic system. This study presents findings obtained from the in-situ vibration measurements and following finite-element analyses of the cooling structure. Comments are made on the updated performance level and damage state of the structure using the results of these measurements and corresponding numerical analyses. An attempt was also made to assess the applicability of traditional displacement-based vulnerability estimation methods in the health monitoring of structures under vibrations with a character different from those due to seismic excitations.

• Earthquakes and Structures
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• 제4권3호
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• pp.285-297
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• 2013

The effect of soil structure interaction (SSI) on seismic response of a multi-degree-of-freedom structure isolated with a friction pendulum system (FPS) is studied. In the analysis, the soil is considered as an elastic continuum and is modeled using the finite element method. The effect of SSI on response of the structure is evaluated for twenty far-field and twenty near-fault earthquake ground motions. The effect of friction coefficient of sliding material of FPS on SSI is also studied. The results of the study show that the seismic response of the structure increases for majority of the earthquake ground motions due to SSI. The sliding displacement and base shear are underestimated if SSI effects are ignored in the seismic analysis of structures isolated with FPS.

• Steel and Composite Structures
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• 제16권3호
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• pp.289-303
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• 2014

In recent, development of construction and design technology gives taller, larger and heavier steel framed structures. With the tendency of increasing high-rise building, this study is strongly related to structural system, one of significant components in structural design. This study presents an innovative structural system, with high performance steel material, diagrid. Its detail, structural analysis, and structural experiments are all included for the development of new structures.

• Geomechanics and Engineering
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• 제5권4호
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• pp.283-297
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• 2013

The aim of this paper is to investigate how the soil-structure interaction affects sloshing response of the elevated tanks. For this purpose, the elevated tanks with two different types of supporting systems which are built on six different soil profiles are analyzed for both embedded and surface foundation cases. Thus, considering these six different profiles described in well-known earthquake codes as supporting medium, a series of transient analysis have been performed to assess the effect of both fluid sloshing and soil-structure interaction (SSI). Fluid-Elevated Tank-Soil/Foundation systems are modeled with the finite element (FE) technique. In these models fluid-structure interaction is taken into account by implementing Lagrangian fluid FE approximation into the general purpose structural analysis computer code ANSYS. A 3-D FE model with viscous boundary is used in the analyses of elevated tanks-soil/foundation interaction. Formed models are analyzed for embedment and no embedment cases. Finally results from analyses showed that the soil-structure interaction and the structural properties of supporting system for the elevated tanks affected the sloshing response of the fluid inside the vessel.