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기업의 사회적 책임 활동과 고객만족은 기업에 대한 고객의 태도 및 반응에 긍정적 영향을 미친다. 하지만 기업의 실질적 성과에 미치는 영향에 관한 선행 연구 결과는 일치하지 않는다. 고객만족 향상과 다양한 사회적 책임 활동의 수행을 위한 기업의 노력과 비용이 지속적으로 증가하는 상황에서 고객만족과 기업의 사회적 책임 활동이 실제로 기업의 성과에 유의한 영향을...

Along with the perspective of relationship marketing (RM), which is a traditional view on business to business marketing in western culture, research...

Combined convection-radiation problems in gray absorbing/emitting/scattering media are investigated numerically. The discrete ordinates interpolation method (DOIM) is incorporated into commercial software (FLUENT) using userdefined functions (UDFs). As preliminary tests, combined conduction/natural convection-radiation problems in a rectangular geometry are solved to validate the accuracy. The original DOIM is modified to solve the radiative heat transfer in an irregular geometry with internal obstacles. Then the combined turbulent forced convection-radiation problem is solved, and the radiation effects are discussed through the profiles of velocity and temperature. Fine agreement with other reference solutions is found. The DOIM promises reliable accuracy and excellent versatility for incorporation into fluid flow codes. Further computational issues are also discussed.

Three thermal transport mechanisms of various filling materials for Vacuum Insulation Panels (VIPs) are theoretically investigated with special emphasis on the solid conduction. As the first, the solid conductivities of porous materials such as powder, foam, fiber and staggered beam subject to external atmospheric compression are derived using simplified elementary cell models. The results show that the solid conductivities of the fiber and staggered beam insulation are lower than those of the powder and foam due to the relatively long thermal path. The second mechanism, i.e., gaseous conductivity shows the lowest for the fine powder among the considered materials due to its smallest pore size. The radiative conductivity as the last is calculated using the diffusion approximation. If radiation shields are installed for the staggered beam, the radiation effect can be lowered to a negligible order of magnitude. The predicted total effective conductivities suggest that the fiber and staggered beam structures are promisingly proper filling materials for VIPs.

To practically apply vacuum insulation panels (VIPs) to buildings or home appliances, VIPs have demanded long-term lifespan with outstanding insulation performance. Service lives of VIPs enveloped with Al-foil and three-layer Al-metallized envelope are calculated. For Al-foil envelope, the service life is longer but edge conduction is too large compared with the Al-metallized envelope. To increase service life even more, the proposed double enveloping method and metal-barrier-added enveloping method are further analyzed. The service lives of the VIP to employ two enveloping methods are calculated. Also, pressure increase and thermal insulation performance characteristics are investigated. For the metalbarrier- added enveloping method, effective thermal conductivity increase with time is close to that of Al-foil envelope, especially, for getter-inserted VIPs. For double enveloping method, if water vapor is perfectly adsorbed, the effect of service life enhancement becomes much greater. From these methods, the VIP can be guaranteed for service life of more than 20 years.

A measurement apparatus is designed and fabricated to measure the effective thermal conductivity (keff) of a VIP (vacuum insulation panel) core specimen under various vacuum states and external loads. The apparatus consists of part for measuring keff, and parts for controlling external load and vacuum condition. Uncertainty of the apparatus is validated by measuring the standard reference material and comparing with commercial devices with VIP samples. Assessed uncertainty is maximum 2.5 % in case of the standard reference material, 10 % in case of VIP samples. Using the apparatus, keff of glass paper under various vacuum levels is examined., {"references":["E. Placido, M. C. Arduini-schuster, J. Kuhn, \"Thermal properties\npredictive model for insulating foams\", Infrared Physics & Technology,\nvol. 46, 2005, pp. 219-231.","J. Fricke, D. Buttner, R. Caps, J. Gross, O. Nilsson, \"Solid conductivity of\nloaded fibrous insulations\", Insul. Mater. Test. Appl., ASTM STP1030,\n1990, pp. 66-78.","Jae-Sung Kwon, Choong Hyo Jang, Haeyong Jung, Tae-Ho Song,\n\"Effective thermal conductivity of various filling materials for vacuum\ninsulation panels\", International Journal of Heat and Mass Transfer, vol.\n52, 2009, pp. 5525-5532.","Michael F. Modest, Radiative heat transfer, 2nd edition, Academic Press,\n2003, pp. 451-454.","A. Roth, Vacuum technology, Elsevier, 3rd edition, 1990, pp.37-58.","Shu-yuan Zhao, Bo-ming Zhang, Xiao-dong He, \"Temperature and\npressure dependent effective thermal conductivity of fibrous insulation\",\nInternational Journal of Thermal Sciences, vol.48, 2009, pp. 440-448.","Majid Bahrami, M. Michael Yovanovich, J. Richard Culham, \"Effective\nthermal conductivity of rough spherical packed beds\", International\nJournal of Heat and Mass Transfer, vol. 49, 2006, pp. 3691-3701.","E. Hummer, Th. Rettelbach, X. Lu, J. Fricke, \"Opacified silica aerogel\npowder insulation\", Thermochimica Acta, vol. 218, 1993, pp.269-276.","J. Xaman, L. Lira, J. Arce, \"Analysis of the temperature distribution in a\nguarded hot plate apparatus for measuring thermal conductivity\", Applied\nThermal Engineering, vol. 29, 2009, pp. 617-623.\n[10] \"Manual on the use of thermocouples in temperature measurement\",\nAmerican Society for Testing and Materials, 1983.\n[11] J. P. Holman, Experimental methods for engineers, McGraw-Hill, 6th\nedition, 1994, pp. 49-57.\n[12] R. Caps, A. Trunzer, D. Buttner, J. Fricke, \"Spectral transmission and\nreflection properties of high temperature insulation materials\", Int. J. Heat\nMass Transfer, vol.27, 1984, pp.1865-1875.\n[13] J. Fricke, U. Heinemann, H. P. Ebert, \"Vacuum insulation panels-From\nresearch to market\", Vacuum, vol.82, 2008, pp. 680-690.\n[14] K. L Johnson, Contact Mechanics, Cambridge university press, 1987, pp.\n84-100."]}

Various engineering models of nongray behavior of combustion products are compared with one another for two types of sample problem. The Curtis-Godson approximation method and the weighted-sum-of-gray-gases-model (WSGGM) are used to compute the emission from a Lorentz line in a non-isothermal path, as the first problem. The Milne-Eddington type WSGGM underestimates the effective line width. Secondly, the gray gas model, the WSGGM and the spectral group model (SGM, a modification of WSGGM) are used to solve one-dimensional inhomogeneous slab problems and are compared with the nongray wide band results. The results from both the WSGGM and the SGM are in good agreement with the reference. The result from the gray gas model is significantly away from those of the other models.