• 한국표면공학회지
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• 제40권4호
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• pp.185-189
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• 2007

A scanning electron microscope (SEM) is a complex system, consisting of many sophisticated components. For a systematic characterization, a $2^4$ full factorial experiment was conducted. The SEM components examined include condenser lens 1 and 2 (denoted as A and B, respectively), and Objective lens (coarse and fine-denoted as C and D respectively). A statistical analysis was conduced to investigate factor effects and variations In response surfaces. Among four factors, main effect analysis revealed that A and D were Identified as the dominant factor. Moreover, B showed conflicting effect against C. The $R^2$ of statistical regression model constructed was about 69.6%. The model generated 3D response surface plots facilitated understanding of complex tactor effects.

• Structural Engineering and Mechanics
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• 제7권5호
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• pp.485-502
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• 1999

Using the continuous Hopfield network model as the basis to solve the general crisp and fuzzy constrained optimization problem is presented and examined. The model lies in its transformation to a parallel algorithm which distributes the work of numerical optimization to several simultaneously computing processors. The method is applied to different structural engineering design problems that demonstrate this usefulness, satisfaction or potential. The computing algorithm has been given and discussed for a designer who can program it without difficulty.

• 한국정보시스템학회지:정보시스템연구
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• 제25권4호
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• pp.63-85
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• 2016

Purpose While the popularity of C2C auction platforms such as eBay is gradually decreased, this domain is still undermined to explain online bidding behaviors. Online bidders sometimes engage in impulsive bidding due to some of the online auction characteristics. Therefore, this study develops and tests a model of the impulsive bidding exhibited by online bidders in C2C auction platforms. Based on S-O-R framework, our model posits that both perceived time-pressure and competition intensity affect cognitive absorption which ultimately influences the impulsive bidding. Design/methodology/approach This study collected survey data from 214 C2C auction participants, who have prior experience on impulsive bidding and tested both measurement model and structural model by using CB-SEM (covariate-based structural equation modelling) technique. In this study, by using AMOS 20.0, we tested the measurement model for its overall fit, item reliability, and validity and further conducted the structural model to test our proposed hypotheses. Findings Based on our results, we found that perceived tim-pressure and competition intensity were positively related to cognitive absorption. We also found that the cognitive absorption was positively associated with impulsive bidding behavior. In this study, by developing our research model in S-O-R framework, we provide an alternative theoretical mechanism to describe online impulsive bidding behavior.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2021년도 학술발표회
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• pp.316-316
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• 2021

Erosion in a watershed is one of the main sources of sediment inflow in dams. While sediment management practices can be performed to reduce and manage sedimentation in reservoirs, managing the sediment inflow before it reaches the reservoir should also be consider. The accurate location of areas with high erosion and deposition rates should be determined in order to propose an appropriate sediment management procedure such as the construction of check dams. In this study, the projected rainfall from HadGEMRA-3 for RCP 8.5, was used in C-SEM, a distributed rainfall-erosion model, to determine the projected spatial erosion patterns in Cheoncheon catchment, which is located in the upstream part of Yongdam Dam.

• Structural Engineering and Mechanics
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• 제5권1호
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• pp.21-32
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• 1997

A new torsional analysis method for multiple cell box based on the Softened Truss Model Theory was developed. This softened truss model unifies shear and torsion to address the problem associated with a torque applied on a box. The model should be very useful for the analysis of a reinforced concrete box under torque, especially for the bridge superstructure with multiple cell box sections.

• 한국환경과학회지
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• 제27권2호
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• pp.83-90
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• 2018

In this study, zeolite (Z-C2) was synthesized using a fusion/hydrothermal method on coal fly ash (FA) discharged from a thermal power plant in the Ulsan area and then analyzed via scanning electron microscopy (SEM) and X-ray diffraction (XRD). The Z-C2 was characterized in terms of mineralogical composition and morphological analysis. The XRD results showed that its peaks had the characteristics of Na-A zeolite in the range of $2{\theta}$ of 7.18~34.18. The SEM images confirmed that the Na-A zeolite crystals had a chamfered-edge crystal structure almost identical to that of the commercial zeolite. The adsorption kinetics of Cu, Co, Mn and Zn ions by Z-C2 were described better by the pseudo-second-order kinetic model more than by the pseudo-first-order kinetic model. The Langmuir model fitted the adsorption isotherm data better than the Freundlich model did. The maximum adsorption capacities of Cu, Co, Mn and Zn ions obtained from the Langmuir model were in the following order : Cu (94.7 mg/g) > Co (77.7 mg/g) > Mn (57.6 mg/g) > Zn (51.1 mg/g). These adsorption capacities are regarded as excellent compared to those of commercial zeolite.

• 디지털콘텐츠학회 논문지
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• 제9권3호
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• pp.379-388
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• 2008

본 논문은 사이버진로상담 활성화(C-C-C-A)의 개념을 재정의 하고 경기지역 인문계 고등학교 수준에서 사이버 상담활성화 영향요인들의 효과를 검정하는데 있다. 이 연구에서, 연구자는 독립변인으로서 3개의 요인들이 <사이버진로상담 활성화>를 증진시킬 것이라는 가정을 하고 있다. 본 가설을 논의하기 위해, AMOS 5.0 프로그램을 사용하여, 2007년 12월, 사이버진로상담 경험자 322명의 학생자료를 분석하였다. 3개의 핵심요소가 사이버진로상담 활성화에 미치는 영향요인을 측정하기 위한 문항들의 신뢰도 검사를 위해서는 탐색적 요인분석이, 사이버 진로상담활성화모형 타당도와 적합도 검정을 위해서는 확인적 요인분석이 시행되었다. 그 결과들은 다음과 같다: 첫째, 3개의 요인들(상담기회 확대, 상담서비스 내실화, 상담서비스체제구축)은 사이버 진로상담 활성화를 증가시킨다. 둘째, 확정요인분석결과로 나타난 적합도 지수들(GFI AGFI, CFI, RMSEA)의 양호함은 사이버진로상담 활성화모형의 통계적 유의미성과 적합도를 증명해 주고 있다. 그러므로, 3개의 선택된 요소들은 사이버진로상담 활성화 모형을 구성하는 유의미한 요소들이라고 말할 수 있다.

• Structural Engineering and Mechanics
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• 제31권4호
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• pp.423-437
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• 2009

In order to perform a step-by-step force-displacement response analysis or dynamic time-history analysis of large buildings with masonry infilled R/C frames, a continuous force-deformation model based on an equivalent strut approach is proposed for masonry infill panels containing openings. The model, which is applicable for degrading elements, can be implemented to replicate a wide range of monotonic force-displacement behaviour, resulting from different design and geometry, by varying the control parameters of the model. The control parameters of the proposed continuous model are determined using experimental data. The experimental program includes fifteen 1/3-scale, single-story, single-bay reinforced concrete frame specimens subjected to lateral cyclic loading. The parameters investigated include the shape, the size, the location of the opening and the infill compressive strength. The actual properties of the infill and henceforth the characteristics needed for the diagonal strut model are based on the assessment of its lateral resistance by the subtraction of the response of the bare frame from the response of the infilled frame.

• Structural Engineering and Mechanics
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• 제22권1호
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• pp.53-70
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• 2006

The paper summarizes the dynamic-based assessment of a reinforced concrete arch bridge, dating back to the 50's. The outlined approach is based on ambient vibration testing, output-only modal identification and updating of the uncertain structural parameters of a finite element model. The Peak Picking and the Enhanced Frequency Domain Decomposition techniques were used to extract the modal parameters from ambient vibration data and a very good agreement in both identified frequencies and mode shapes has been found between the two techniques. In the theoretical study, vibration modes were determined using a 3D Finite Element model of the bridge and the information obtained from the field tests combined with a classic system identification technique provided a linear elastic updated model, accurately fitting the modal parameters of the bridge in its present condition. Hence, the use of output-only modal identification techniques and updating procedures provided a model that could be used to evaluate the overall safety of the tested bridge under the service loads.

• Asia pacific journal of information systems
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• 제29권1호
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• pp.1-34
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• 2019

The concept of e-Government was first developed and implemented in industrialised countries. Consequently, it should not be assumed that this concept is automatically appropriate for developing countries. This study aims to examine the roles of perceived support quality and support satisfaction in the context of government-to-citizen (G2C) transactions towards behavioural intention and usage in developing countries. To test the proposed model, the official website of Kuwait Government Online Services (KGOS) was selected. A survey with a total of 628 responses was analysed using Structural Equation Modelling (SEM) to investigate the goodness of fit of the model and the underlying indicators. The findings confirm the significance of support quality perceived by citizens and provide insights to explain citizens' intention to use e-Government systems.