• 대한교통학회지
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• 제28권4호
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• pp.119-128
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• 2010

통행자의 통행수단선택행태는 개인의 사회경제적 속성과 수단의 속성뿐만 아니라 통행자 개인의 잠재된 통행행태 즉, 통행행태적 선호도 역시 큰 영향을 미친다. 통행수단선택행태에 특정한 영향을 미치는 잠재통행행태를 수단선택모형에 반영한다면 비관측요인에서 기인하는 오차를 크게 줄일 수 있고, 통행행태에 대한 다양하고 보다 합리적인 해석이 가능하다. 본 연구에서는 한강 수상대중교통 도입에 따른 수단선택행태조사 자료를 활용하여 잠재변수를 정의하고 새로운 수단에 대한 분석이 가능한 RP/SP 결합모형을 구축하였다. 잠재변수는 행태설문조사자료를 기반으로 요인분석을 통해 계량화하였다. 모형구축결과 통행자들의 잠재된 통행행태는 수단선택행태에 유의한 영향을 미치고, 잠재변수를 반영한 경우 모형의 적합도가 향상되었다. 또한 잠재행태 관점에서도 RP/SP 결합모형이 SP모형에 비해 합리적인 것으로 분석되었다.

• 한국항해항만학회지
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• 제43권3호
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• pp.160-165
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• 2019

선원의 행동은 해양사고에 있어서 주요한 원인이다. 본 연구에서는 은닉 마르코프 모델(Hidden Markov Model)에 기반하여 선원의 행동을 모델링하였다. 그런 후, 모델에서 추정한 행동의 경로분석을 통하여 어떠한 상황과 절차 그리고 오류에 의해서 해양사고가 발생되는지를 해석하였다. 모델 구현을 위하여, 선원의 행동을 해양안전심판원에서 간행된 재결 요약서에서 관측하였고, 관측한 결과는 SRKBB(Skill-, Rule-, and Knowledge-Based Behavior)를 기반으로 한 행동분류 프레임워크를 이용하여 HMM 학습에 적합한 행동 데이터로 변환하였다. 선박유형별 선원의 행동을 모델링한 결과, 선박 유형별로 차별성이 있음을 확인하였고, 선원이 우선적으로 행한 행동경로의 식별이 가능하였다. 연구 결과, 본 연구에서 제안한 모델링 기법은 선원의 행동경로 예측에 적용 가능할 뿐만 아니라 해양사고 예방에 필요한 선원 행동 보정을 위한 우선순위 결정에 기여할 수 있을 것으로 기대된다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 추계학술발표회논문집(1)
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• pp.423-428
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• 1995

Simulation models have been developed to predict the overall behavior of the CANDU plant systems during normal operational transients. For real time simulation purpose, simplified thermal hydraulic models are applied with appropriate system control logics, which include primary heat transport system solver with its component models and secondary side system models. The secondary side models are mainly used to provide boundary conditions for primary system calculation and to accomodate plant power control logics. Also, for the effective use of simulation package, hardware oriented basic simulation network has been established with appropriate graphic display system. Through validation with typical plant power maneuvering cases using proven plant performance analysis computer code, the present simulation package shows reasonable capability in the prediction of the dynamic behavior of plant variables during operational transients of CANDU plant, which means that this simulation tool can be utilized as a basic framework for full scope simulation network through further improvements.

• Advances in concrete construction
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• 제3권3호
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• pp.161-185
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• 2015

FRP confining is a widely used method for seismic retrofitting of concrete columns. Several studies investigated the stress-strain behavior of FRP confined concrete prisms with square and rectangular sections both experimentally and analytically. In some studies, the monotonic stress-strain behavior of confined concrete was investigated and compressive strength models were developed. To study the reliability of these models, thorough statistical tests are required. This paper aims to investigate the reliability of the presented models using statistical tests including t-test, wilcoxon rank sum test, wilcoxon signed rank test and sign test with a level of significance of 5%. Wilk Shapiro test was also employed to evaluate the normality of the data distribution. The results were compared for different cross section and confinement types. To see the accuracy of the models when there were no significant differences between the results, the coefficient of confidence was used.

• 정보관리학회지
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• 제21권2호
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• pp.211-233
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• 2004

웹은 지금까지 연구되어온 전통적인 정보검색 시스템과는 차별되는 새로운 정보환경이므로 웹상에서 발생하는 이용자와 정보검색 시스템 간의 상호작용에 대한 이해를 위해 새로운 관점에서의 연구가 충분히 이루어져야 하며 이러한 연구를 뒷받침해줄 웹 기반 정보탐색 패러다임이 정착될 필요가 있다. 이러한 맥락에서 본 연구는 웹 정보탐색행위를 연구한 문헌에서 제시된 이론적 모형들을 검토하고 비교 분석하였다. Wang, Hawk, Tenopir, Hsieh-Yee, Choo, Detlor, Turnbul, Chun과 Cooper, Rieh, Spink의 연구에서 제시된 모형들이 논의되었다. 분석 결과, 웹 정보탐색 모형은 크게 상호작용 모형, 정보탐색행위 모형, 평가 모형으로 구분되며, 전통적인 정보탐색과정 모형에 비해 복합요인들의 상호작용과 정보탐색행위의 비선형적 관점이 강조되었다는 특징을 갖는다.

• 보건교육건강증진학회지
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• 제27권4호
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• pp.177-188
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• 2010

Objectives: The aim of this study was to examine factors related to smoking behavior, and to develop multilevel communication strategies for smoking cessation. Methods: This paper reviewed theories and empirical findings with currents ecological models to develop communication strategies. Theory comparison was also performed to identify important mediators in the process of smoking cessation. Results: Factors that have been identified to influence smoking behavior ranges from individual perception, attitudes and self efficacy toward smoking to organizational norms, regulations, community capacity, media advocacy and public smoking regulation policy. In order to address these multi-level determinants of smoking behavior, objectives and strategies for smoking cessation intervention were developed utilizing ecological perspectives to cover intrapersonal, interpersonal(mainly family member and peers), organizational and community/public policy level factors. Conclusion: Multilevel approaches have advanced the existing knowledge on determinants of health behaviors. New direction of research focusing on testing multilevel intervention approaches should be expanded to inform the efficacy of applying social ecological models to health behavior change process.

• Asian Journal of Business Environment
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• 제6권4호
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• pp.5-12
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• 2016

Purpose - Not all firms are able to completely eliminate the risk arising out of the crisis. Success hides in the ability to perceive the market expectations accurately and take correct decisions. This study aims to analyze the firms' decisions at gross-root level. Research Design, Data, and Methodology - Primary data is obtained with the help of specially designed questionnaires from the agriproducts export firms that are members of export union of Turkey. The study is based on four theoretical structures: general planned behavior theory model, perception-leading behavior control and subjective norm model, perceived-behavioral-control leading perception and subjective norm models, and perceptions and subjective norms leading behavior control model. Structural Equation Models (SEM) is used to conduct the empirical analysis. Results - The findings show perceptions and subjective norms leading behavior control model as the best one, concluding that the environmental pressures and positive perceptions have significant effect on the strategic decisions of the agriproducts export firms. Conclusion - Policy tools like creating positive perception in the markets, providing sufficient information and financial support to the firms and increasing market competition can be used effectively to achieve the said objective.

• Korean Journal of Acupuncture
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• 제38권2호
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• pp.75-99
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• 2021

Objectives : The purpose of this study is to analyze animal behavioral changes and related neurobiological mechanisms in recent studies using animal models with pain and depression. Methods : We conducted database search in Pubmed, NDSL, and EMBASE up to January 2021. Included studies were classified as depression-like behavior observed in pain model, pain-like behavior observed in depression model, and pain and depression comorbidity model. The results of pain- and depression-like behaviors, the changes of neurobiological mechanisms, and the treatment methods such as drugs, natural substance-derived chemicals, or acupuncture were analyzed. Results : We included 124 studies (81 studies in depression-like behavior observed in pain model, 19 studies in pain-like behavior observed in depression model, and 24 studies in pain and depression comorbidity model). Pain and depression comorbidity animal models were induced using various methods by drugs or surgery. Von frey test, a method for evaluating mechanical allodynia was the most commonly used for measuring pain-like behavior and the forced swimming test was the most commonly used for measuring depression-likes behavior. The changes of neurobiological factors, such as decrease of 5-hydroxytryptamine and increase of oxidative stress and pro-inflammation cytokines were generally changed in the frontal cortex, hippocampus, thalamus, and spinal cord in all types of models. For treating pain and depression-like behaviors, various types of drugs such as antidepressant, tranquilizer, analgesic, and natural substance-derived chemicals were used. Acupuncture treatment was used in 4 studies. Conclusions : In the future, more diverse studies on the combined model of pain and depression need to be conducted. In addition, it is necessary to establish a mechanistic basis for the development of various treatments by identifying the common mechanisms of pain and depression.

• Journal of Pharmaceutical Investigation
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• 제29권3호
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• pp.193-203
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• 1999

In order to investigate systematically the steady shear flow properties of aqueous po1y(ethylene oxide) (PEO) solutions having various molecular weights and concentrations, the steady flow viscosity has been measured with a Rheometrics Fluids Spectrometer (RFS II) over a wide range of shear rates. The effects of shear rate, concentration, and molecular weight on the steady shear flow properties were reported in detail from the experimentally measured data, and then the results were interpreted using the concept of a material characteristic time. In addition, some flow models describing the non-Newtonian behavior (shear-thinning characteristics) of polymeric liquids were employed to make a quantitative evaluation of the steady flow behavior, and the applicability of these models was examined by calculating the various material parameters. Main results obtained from this study can be summarized as follows: (1) At low shear rates, aqueous PEO solutions show a Newtonian viscous behavior which is independent of shear rate. At shear rate region higher than a critical shear rate, however, they exhibit a shear-thinning behavior, demonstrating a decrease in steady flow viscosity with increasing shear rate. (2) As an increase in concentration and/or molecular weight, the zero-shear viscosity is increased while the Newtonian viscous region becomes narrower. Moreover, the critical shear rate at which the transition from the Newtonian to shear-thinning behavior occurs is decreased, and the shear-thinning nature becomes more remarkable. (3) Aqueous PEO solutions show a Newtonian viscous behavior at shear rate range lower than the inverse value of a characteristic time $1/{\lambda}_E$, while they exhibit a shear-thinning behavior at shear rate range higher than $1/{\lambda}_E$. For aqueous PEO solutions having a broad molecular weight distribution, the inverse value of a characteristic time is not quantitatively equivalent to the critical shear rate, but the power-law relationship holds between the two quantities. (4) The Cross, Carreau, and Carreau-Yasuda models are all applicable to describe the steady flow behavior of aqueous PEO solutions. Among these models, the Carreau-Yasuda model has the best validity.

• Structural Engineering and Mechanics
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• 제13권5호
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• pp.465-478
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• 2002

This study lays emphasis on the development of efficient analytical models for a multistory structure with wings, including the in-plane deformation of floor slabs. For this purpose, a multistory structure with wings is regarded as the combination of multistory structures with rectangular plan and their junctions. In addition, a multistory structure with a rectangular plan is considered to be an assemblage of two-dimensional frames and floor slabs connecting two adjacent frames at each floor level. This modeling, concept can be easily applied to multistory structures with plans in the shape of L, T, Y, U, H, etc. To represent the in-plane deformation of floor slabs efficiently, a two-dimensional frame and the floor slab connecting two adjacent frames at each floor level are modeled as a stick model with two degrees of freedom per floor and a stiff beam with shear deformations, respectively. Three models are used to investigate the effect of in-plane deformation of the floor slab at the junction of wings on the seismic behavior of structures. Based on the comparison of dynamic analysis results obtained using the proposed models and three-dimensional finite element models, it could be concluded that the proposed models can be used as an efficient tool for an approximate analysis of a multistory structure with wings.