• 제목/요약/키워드: Theoretical model

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Dust Disks Around Young Stellar Objects

  • Suh, Kyung-Won
    • Journal of Astronomy and Space Sciences
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    • 제33권2호
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    • pp.119-126
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    • 2016
  • To reproduce the spectral energy distributions (SEDs) of young stellar objects (YSOs), we perform radiative transfer model calculations for the circumstellar dust disks with various shapes and many dust species. For eight sample objects of T Tauri and Herbig Ae/Be stars, we compare the theoretical model SEDs with the observed SEDs described by the infrared space observatory and Spitzer space telescope spectral data. We use the model, CGPLUS, for a passive irradiated circumstellar dust disk with an inner hole and an inner rim for the eight sample YSOs. We present model parameters for the dust disk, which reproduce the observed SEDs. We find that the model requires a higher mass, luminosity, and temperature for the central star for the Herbig Ae/Be stars than those for the T Tauri stars. Generally, the outer radius, total mass, thickness, and rim height of the theoretical dust disk for the Herbig Ae/Be stars are larger than those for the T Tauri stars.

결혼생활의 질과 안정성 : 이론적 모델의 검증 (Marital Quality and Stability : A Theoretical Model)

  • 김영희
    • 대한가정학회지
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    • 제37권6호
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    • pp.77-96
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    • 1999
  • The purpose of this study was to examine the effect of family-of-origin, personal and spousal characteristics, mediated by communication and problem-solving behavior, on marital quality and stability. On the basis of previous literature, the theoretical model was specified, estimated, and evaluated for adequacy of statistical fit for samples of 214 married women. Although the initial model was not supported by data, the revised model fitted the data adequately. Results of structural equation modeling indicated family-of-origin and communication behavior directly affected marital quality. However, the personal and spousal characteristics were linked with marital quality and stability only if they were mediated by communication and problemsolving behavior. Communication behavior was strongly related to marital quality and stability both directly and indirectly through problem-solving behavior. The model also showed marital quality can be an antecedent variable for marital stability. The findings of results is to generate more broad-minded thinking about how communication behavior, marital quality, and marital stability are interrelated.

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병원정보시스템의 성공 요인과 성과 모형에 관한 연구 (An Empirical Study on the Success Factors and Performance Model of Hospital Information Systems)

  • 유일;김미
    • Asia pacific journal of information systems
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    • 제12권1호
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    • pp.45-65
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    • 2002
  • Factors influencing the success or failure of information systems(IS) have been discussed in many literature. However, limited theoretical development or empirical research have examined the effectiveness of hospital information systems(HIS). This study set out the research model of influencing factors and the performance of HIS through theoretical studies based on Management Information Systems, and then empirically tested hypotheses related to the model. The model was tested using LISREL analysis on the sample of 274 respondents who have worked with the HIS. The major results of this study are as follows: First, system characteristics and organizational characteristics have a statistically significant influence on user satisfaction. Second, the hypothesis 3, proposing that computer self-efficacy would relate positively to user satisfaction, was not supported by the results, though. According to these results, system quality, information quality, service quality and support of top management are very important variables for IS success. The study's findings also indicate DeLone and McLean's model is correct in proposing that the indirect relationship between influencing factors and organizational effectiveness, mediated by user satisfaction, is an important one.

Collagen의 수화에 대한 이론적 연구 (Theoretical Study of the Hydration of Collagen)

  • 이종명;전무식
    • 대한화학회지
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    • 제22권6호
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    • pp.403-411
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    • 1978
  • Collagen의 model compound인 poly(Gly-Pro-Pro)의 수화에 관해서 empirical ppotential energy 함수를 사용하여 이론적으로 연구하였다. 물 분자와 model compound 간의 상호작용 energy를 최소화시켜서 물 분자들의 위치와 결합 energies를 계산하였다. 다음에는 일차수화층에 물이 붙음으로써 생기는 안정화 energy를 계산하고, 전체 안정화에 기여하는 여러 energy components의 기여도에 대해 논의하였다.

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교육에서의 소진에 관한 이론적 고찰 (Theoretical Review on Burnout Symptoms in Education)

  • 이상민;안성희
    • 의학교육논단
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    • 제16권2호
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    • pp.57-66
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    • 2014
  • Burnout research has mostly been performed in human service fields. However, it has recently been expanded to cover diverse settings and even non-occupational samples, such as students. In this study, we defined the construct of academic burnout, which is the burnout experienced by students. Next, we described the concept of academic burnout by introducing measurements for assessing academic burnout. On the basis of the demand-control model (DCM) and effort-reward imbalance model (ERIM), which are the most predominant theoretical burnout models, we described the causal factors and the pathway to experiencing academic burnout symptoms. The ERIM was a more influential model than the DCM when explaining the academic burnout of Korean students. Based on the results of previous longitudinal studies on academic burnout, we recognized emotional exhaustion and academic inefficacy as the initial symptoms of academic burnout. Finally, we discussed the prevention and intervention programs with specific components that should be included in those programs.

보 제진 프레임의 진동응답해석 (Vibration Reaponse Analysis of frames with energy absober installed in Beams)

  • 이호
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 1997년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 1997
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    • pp.159-166
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    • 1997
  • The purpose of this thesis is to derive a theoretical model of the hysteretic resistance of the visco-elastic damper based on test results of harmonic excitation and to investigate of the basis of theory and experiment the effect of vibration control and response characteristics of portal frames degree vibration systems provided with the damper. The behaviour of a visco-elastic degree under dynamic loading is idealized by a model of the theory of visco-elasticity, i.e. a four-parameter model formed as a parallel combination of Maxwell fluid and Kelvin-Voigh models and its constitutive equation is derived. The model parameters are determined for a tested damper from the datas of harmonic excitation tests. The theoretical model of the damper is incorporated in equation fo motion of single degree of freedom. A computer program for solving the equation is written using Runge-kuttas's numerical integration scheme. Using this analysis program test cases of the earthquake excitation are simulated and the results of the simulation are the results of the simulation are the results of the simulation are compared with the test results.

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주거생활양식에 대한 이론적 접근 (Theoretical Approach about Housing Life Style)

  • 이연복
    • 대한가정학회지
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    • 제34권4호
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    • pp.103-117
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    • 1996
  • This study is a theoretical approach by literature about life style and housing life style. The purpose of this research is making an analysis model of housing life style which can be used as a conceptual framework in empirical study. the theme of‘Life style’was studied mainly in the area of consumerism and housing. Model was made to explore the sub-domain of new analysis model by the microsociological approach. As results, 1) Independent variable of housing life style research model must be selected to be possible of comparison in effect of objective and subjective variable and in effect of predictive function and well-being function of housing life style. 2) Sub-domain of housing life style must be consisted of value orientation of family life, consumption in house, consumer durables, furniture., and propensity to using space. 3) Conceptual model of housing life style must be tested in empirical study to know what is the housing adjustment behavior of individual family, to improve quality of housing life and to suggest housing policy for family as a consumer.

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인터넷 시작페이지 포털사이트 결정요인과 만족에 관한 연구 (A Study on the Determinants and Satisfaction of Portal Cite in Internet Initiation Page)

  • 이제홍
    • 통상정보연구
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    • 제8권1호
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    • pp.33-50
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    • 2006
  • This research develops, and empirically test a model for explaining/predicting the Determinants and Satisfaction of Portal Cite in Internet Initiation Page. Also this paper describes a theoretical model for investigating the service quality satisfaction in the Internet Initiation Page. This research is the first to empirical test the causal relationships in determinants of Portal Cite. The model of the satisfaction for Portal Cite are tested here using data from 224 samples. Based on the research model, a comprehensive set of hypotheses is formulated and a methodology for testing them is outlined. some of the hypotheses are tested empirically to demonstrate the applicability of the theoretical model. In examining the relationships of the determinants factors, satisfaction show in significantly by Convenience, Information Provided, Entertainments, Interaction but that show in not significantly by the Trustworthiness, In addition, Portal Cite in Internet Initiation Page shows indirect effect between customer satisfaction and referral.

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A numerical and theoretical investigation on composite pipe-in-pipe structure under impact

  • Wang, Yu;Qian, Xudong;Liew, J.Y. Richard;Zhang, Min-Hong
    • Steel and Composite Structures
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    • 제22권5호
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    • pp.1085-1114
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    • 2016
  • This paper investigates the transverse impact response for ultra lightweight cement composite (ULCC) filled pipe-in-pipe structures through a parametric study using both a validated finite element procedure and a validated theoretical model. The parametric study explores the effect of the impact loading conditions (including the impact velocity and the indenter shape), the geometric properties (including the pipe length and the dimensions of the three material layers) as well as the material properties (including the material properties of the steel pipes and the filler materials) on the impact response of the pipe-in-pipe composite structures. The global impact responses predicted by the FE procedure and by the theoretical model agree with each other closely. The parametric study using the theoretical approach indicates the close relationships among the global impact responses (including the maximum impact force and the maximum global displacement) in specimens with the equivalent thicknesses, proposed in the theoretical model, for the pipe-in-pipe composite structures. In the pipe-in-pipe composite structure, the inner steel pipe, together with the outer steel pipe, imposes a strong confinement on the infilled cement composite and enhances significantly the composite action, leading to improved impact resistance, small global and local deformations.

Differential settlements in foundations under embankment load: Theoretical model and experimental verification

  • Wang, Changdan;Zhou, Shunhua;Wang, Binglong;Guo, Peijun;Su, Hui
    • Geomechanics and Engineering
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    • 제8권2호
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    • pp.283-303
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    • 2015
  • To research and analyze the differential settlements of foundations specifically, site investigations of existing railways and metro were firstly carried out. Then, the centrifugal test was used to observe differential settlements in different position between foundations on the basis of investigation. The theoretical model was established according to the stress diffusion method and Fourier method to establish an analytical solution of embankment differential settlement between different foundations. Finally, theoretical values and experimental values were analyzed comparatively. The research results show that both in horizontal and vertical directions, evident differential settlement exists in a limited area on both sides of the vertical interface between different foundations. The foundation with larger elastic modulus can transfer more additional stress and cause relatively less settlement. Differential settlement value decreases as the distance to vertical interface decreases. In the vertical direction of foundation, mass differential settlement also exists on both sides of the vertical interface and foundation with larger elastic modulus can transfer more additional stress. With the increase of relative modulus of different foundations, foundation with lower elastic modulus has larger settlement. Meanwhile, differential settlement is more obvious. The main error sources in theoretical and experimental values include: (a) different load form; (b) foundation characteristics differences; (c) modulus conversion; (d) effect of soil internal friction.