• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.416-421
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• 2010

The north and south panel of a geostationary satellite are used for radiator panels to reject internal heat dissipation of electronics units and utilize several heat pipe networks to control the temperatures of units and the satellite within proper ranges. The design of these panels is very important and essential at the conceptual design and preliminary design stage so several thousands of nodes of more are utilized in order to perform thermal analysis of panel. Generating a large number of nodes(meshes) of the panel takes time and is tedious work because the mesh can be easily changed and updated by locations of units and heat pipes. Also the detailed panel model can not be integrated into spacecraft thermal model due to its node size and limitation of commercial satellite thermal analysis program. Thus development of a program was required in order to generate detailed panel model, to perform thermal analysis and to make a reduced panel model for the integration to the satellite thermal model. This paper describes the development and the verification of panel thermal analysis program with ist main modules and its main functions.

• Journal of computational fluids engineering
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• v.15 no.3
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• pp.66-72
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• 2010

The north and south panel of a geostationary satellite are used for radiator panels to reject internal heat and utilize several heat pipe networks to control the temperatures of units and the main structures of satellite within proper ranges. The design of these panels is very important and essential at the conceptual design and preliminary satellite design stage, so several thousands of nodes or more are utilized in order to perform detailed thermal analysis of panel. Generating a large number of panel nodes takes time and is tedious work because the nodes can be easily changed and updated by locations of units and heat pipes. Also the detailed panel model can not be integrated into spacecraft thermal model due to its node size and limitation of commercial satellite thermal analysis program. Thus development of a program was required to generate a detailed panel model, to perform thermal analysis and to make a reduced panel model for the integration to the satellite thermal model. This paper describes the development and the verification of the panel thermal analysis program with its main modules and functions.

• Journal of KSNVE
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• v.9 no.2
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• pp.248-257
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• 1999

This paper presents the model updating of an equipment panel by using modal test and sensitivity analysis. The equipment panel is one of the major structures of communication satelite, on which broadcasting and communication equipments are mounted. For high rigidity and light weight, the panel was designed as an aluminum honeycomb sandwich panel. In addition, heat pipes were embedded in the panel for thermal control. It is essential to improve the finite element model of a spacecraft structure by using modal test in order to verify that the satellite is designed and fabricated with adequate margin under launch environment. In this paper, Young's modulus of aluminumfacesheet was selected as a modified parameter in the sensitivity analysis. The effect of boundary conditions on model improvement was also investigated.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.49-52
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• 2008

The design strength of panel zones, which was based on Krawinkler model, was investigated by comparing it with existing test and FEM results. The design strength overestimates of the strength of panel zones with thick column flange while it matches well with the strength of panel zones with thin column flange. More extensive studies are needed to develop a mathematical model which can properly define the inelastic behavior of panel zones with various column flange thicknesses and to determine a more rational design strength.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1998.04a
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• pp.114-121
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• 1998

This paper presents the model updating of an equipment panel by using modal test and sensitivity analysis. The equipment panel is one of the major structures of communication satellite, on which broadcasting and communication equipments are mounted. For high rigidity and light weight, the panel was designed as an aluminum honeycomb sandwich panel. In addition, heat pipes were embedded in the panel for thermal control. It is essential to improve the finite element model of a satellite by using modal test in order to verify the satellite is designed with adequate margin under launch environment. In this paper, Young's modulus of aluminum facesheet was selected as a modified parameter by sensitivity analysis. The effect of rotational springs of boundary points was also considered.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.04a
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• pp.293-300
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• 2004

As the structure is taller and its member is larger, the effect of the deformation of Panel zone on the displacement of structure becomes larger. The analysis using the centerline dimensions in the steel moment frame structure can not consider the accurate effect of panel ton And the finite element analysis using infinitesimal solid and shell element is impractical for the total tall building structure. Therefore, this paper proposes the analytical model using linear element in order to be able to evaluate the reasonable deformation of panel zone. the proposed analytical model makes the analysis of the building structure simple and ease because it uses the only linear elements. In addition it can easily incorporate the various parameters affecting the deformation of panel zone. In order to prove the validith of the prosed analytical model, the analysis result using the proposed analytical model is compared with the result using finite element analysis with shell element

• Health Policy and Management
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• v.29 no.3
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• pp.332-341
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• 2019

Background: This study analyzes the effects of the individual's health behavior on the health and the medical demand for the management of health and medical expenses. Methods: This study uses the Korea Health Panel Survey data from 2010 to 2015. We utilize the panel ordered logit model and the panel Tobit model with the subjective health status and the medical expenses as the dependent variables. Results: Chronic diseases would cause the deterioration of his or her health and the increase in medical expenses. Smoking and drinking alcohol would deteriorate one's health. The total amount of cigarettes increases medical expenses. Exercises could make people healthier, whereas excessive exercise might increase medical expenses. Private health insurance would increase medical expenses. Conclusion: Since health could reduce the medical expenses, people should promote one's health by changing one's behavior for health.

• Journal of computational fluids engineering
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• v.19 no.4
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• pp.37-44
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• 2014

A detailed satellite panel thermal model composed of more than thousands nodes can not be directly integrated into a spacecraft thermal model due to its node size and the limitation of commercial satellite thermal analysis programs. For the integration of the panel into the satellite thermal model, a reduced thermal model having proper accuracy is required. A thermal model reduction method was developed and validated by using a geostationary satellite panel. The temperature differences of main components between the detailed and the reduced thermal model were less than $1^{\circ}C$ in steady state analysis. Also, the dynamic responses of the detailed and the reduced thermal model show very similar trends. Thus, the developed reduction method can be applicable to actual satellite thermal design and analysis with resonable accuracy and convenience.

• Communications for Statistical Applications and Methods
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• v.23 no.2
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• pp.179-187
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• 2016

The fixed effects panel probit model faces "incidental parameters problem" because it has a property that the number of parameters to be estimated will increase with sample size. The maximum likelihood estimation fails to give a consistent estimator of slope parameter. Unlike the panel regression model, it is not feasible to find an orthogonal reparameterization of fixed effects to get a consistent estimator. In this note, a hierarchical Bayesian model is proposed. The model is essentially equivalent to the frequentist's random effects model, but the individual specific effects are estimable with the help of Gibbs sampling. The Bayesian estimator is shown to reduce reduced the small sample bias. The maximum likelihood estimator in the random effects model is also efficient, which contradicts Green (2004)'s conclusion.

• The Korean Journal of Applied Statistics
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• v.25 no.6
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• pp.933-945
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• 2012

In this paper we used the KLIPS(Korean Labor and Income Panel tudy) data that surveyed from 2006(wave 9) to 2009(wave 12). Other previous studies are concerned with the panel attrition in the early wave, but this study classifies the response pattern and investigates some factors that influence panel attrition when the panel tends to stabilize. It was revealed that panel attrition was influenced by relocation and housing type through the logit model. Besides it was appeared that panel attrition was affected by the monthly living expenses and the overall household income through the decision tree.