• Journal of the Korean Society of Safety
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• v.24 no.5
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• pp.48-56
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• 2009

This paper presents the procedure for the optimal design of a PSC-I girder bridge considering life cycle cost (LCC). The load carrying capacity curves for the concrete deck, PSC-I girder and $\pi$-type pier were derived and used for the estimate of service lives. Total life cycle cost for the service life was calculated as sum of initial cost, damage cost, maintenance cost, repair and rehabilitation cost, user cost, and disposal cost. The advanced First Order Second Moment method was used to estimate the damage cost. The optimization method was applied to the design of PSC-I girder bridge. The objective function was set to the annual cost, which is defined by dividing the total life cycle cost by the service life, and constraints were formulated on the basis of Korean Standards. The optimal design was performed for various service lives and the effects of design factors were investigated.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.51 no.3
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• pp.142-148
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• 2002

Considerable progress has been made in organic photorefractive materials, since the first observation of photorefractive phenomena from organic materials. Within recent years, a large number of organic photorefractive materials, especially amorphous materials, have been developed based on polymeric composites, fully functional polymers and the multi-functional chromophore approach. Among these organic photorefractive materials, some of them containing carbazole components as a charge transporting function have been demonstrated to exhibit high performance photorefractive effects. The carbazole building blocks with charge transporting function or multifunctions play a very important role in photorefraction. In this paper, it confirmed that acceptor-substituted carbazoles show the multifunctionality both of photoconductivity and electro-optic(EO) activity and photorefractive materials newly can be developed with acceptor-substituted carbazoles.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.2
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• pp.180-192
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• 1998

Enthalpy transport in a pulse tube was investigated by two-dimensional analysis of mass, momentum and energy equations assuming that the axial temperature gradient in the pulse tube is constant. Time-averaged second-order conservation equations of mass, momentum and energy were used to show the existence of steady mass streaming and enthalpy streaming. Effects of axial temperature gradient, velocity amplitude ratio and heat transfer between the gas and the wall on the steady mass streaming and enthalpy streaming were shown. Enthalpy loss due to the steady mass streaming is zero for basic and orifice pulse tube refrigerators, but it is proportional to the axial temperature gradient and steady mass flow rate through a pulse tube for double inlet pulse tube refrigerators.

• International Journal of Air-Conditioning and Refrigeration
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• v.7
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• pp.33-44
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• 1999

Enthalpy transport in a pulse tube was investigated by two-dimensional analysis of mass, momentum and energy equations assuming that the axial temperature gradient in the pulse tube was constant. The time-averaged second-order conservation equations of mass, momentum and energy were used to show the existence of steady mass and enthalpy streaming. Effects of the axial temperature gradient, velocity amplitude ratio, and heat transfer between the gas and the tube wall On the steady mass and enthalpy streaming were shown. Enthalpy loss due to the steady mass streaming is zero for basic and orifice pulse tube refrigerators, but it is proportional to the axial temperature gradient and steady mass flow rate through a pulse tube for double inlet pulse tube refrigerators.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.3
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• pp.1-7
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• 2014

The purpose of this study is to present the Market Orientation affects to Enterprise Management Performance. In order to carry out this research, we obtained 212 survey sheets and inspected ten assumptions based on the reliability, validity of the questionnaires. The results of regression analysis are summarized as follows; First, the factor of Market Orientation, intelligence generation, doesn't influence on the Enterprise Management Performance significantly. Second, the element of Market Orientation, information dissemination, doesn't have an important effect on the Enterprise Management Performance. Finally, the requisite of Market Orientation, information response, affects to Enterprise Management Performance significantly. Based on the results, the parts with intelligence generation and information dissemination will be improved in the manufacturer of the small businesses.

• Journal of the Korea Safety Management & Science
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• v.18 no.1
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• pp.191-201
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• 2016

The paper examines how servant leadership and organizational identification contributed to explaining innovative behavior. In order to verify the relationships and mediating effect, data were collected from 298 individuals in employees working in small and medium-sized firms at Jinju, Changwon, Gimhae, Busan City to test theoretical model and its hypotheses. All data collected from the survey were analyzed using with SPSS 18.0. This study reports findings as follows: first, the relationship between the servant leadership and the organizational identification is positively related. Second, there was also a positive correlation between the organizational identification and the innovative behavior. Third, the relationship between the servant leadership and the innovative behavior is positively related. Finally, the organizational identification played as a partial mediator on the relationship between servant leadership and innovative behavior. Based on these findings, the implications and the limitations of the study were presented including some directions for future studies.

• Water for future
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• v.29 no.6
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• pp.203-215
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• 1996

A physically based model for rainfall-runoff simulation in agricultural watersheds equipped with tile drains is developed from the TOPMODEL framework. The model is based on detailed topographical information provided by the Digital Elevation Model (DEM), which is available in the Geographic Information System GRASS. Nine possible flow generation scenarions are suggested and used in the development of the model. The storage and delaying effects in the soil matrix and in the tile system are simulated with a second order linear reservoir. The model can identify the portions of the hydrators resulting from tile flow, subsurface flow and surface runoff.

• Structural Engineering and Mechanics
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• v.21 no.5
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• pp.519-537
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• 2005

A new generalized Bernoulli/Timoshenko beam-column element on a two-parameter elastic foundation is presented herein. This element is based on the exact solution of the differential equation which describes the deflection of the axially loaded beam resting on a two-parameter elastic foundation, and can take into account shear deformations, semi - rigid connections, and rigid offsets. The equations of equilibrium are formulated for the deformed configuration, so as to account for axial force effects. Apart from the stiffness matrix, load vectors for uniform load and non-uniform temperature variation are also formulated. The efficiency and usefulness of the new element in reinforced concrete or steel structures analysis is demonstrated by two examples.

• Journal of Families and Better Life
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• v.21 no.6
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• pp.69-79
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• 2003

The purpose of this study was to examine the effects of social norms and personal ethics on recycling behavior. For this purpose, survey data from four hundred and fifty seven individuals were collected and analyzed using an SPSS program. The major findings were as follows: First, social norms had a positive impact on personal ethics and recycling behavior. Second, personal ethics significantly affected recycling behavior. Third, awareness of the consequences of recycling behavior (AC) and ascription of responsibility for environmental problems(AR) did not significantly translate personal ethics into actual recycling behavior. Fourth, ascription of responsibility for environmental problems(AR) and awareness of consequences of recycling behavior(AC) affected recycling behavior. These results suggest that in order to encourage recycling behavior, it is necessary to inform and educate the public so as to enhance social norms and personal ethics.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.9
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• pp.442-445
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• 2006

In order to realize the commercial application of HTSC materials, it is necessary to develop the fabrication process of high Tc oxide superconductor materials with desired shape and for practical application and high critical current density as well as good mechanical strength which can withstand high lorenz force generated at high magnetic field. Much studies have been concentrated to develop the fabrication technique for high critical current density but still there are a lot of gap which should be overcome for large scale application of HTSC materials at liquid nitrogen temperature. Recently some new fabrication techniques have been developed for YBaCuO bulk superconductor with high mechanical strength and critical current density. In this project, the establishment of fabrication condition and additive effects of second elements were examined so as to improve the related properties to the practical use of YBaCuO superconductor, and we reported the production of the YBaCuO high Tc superconductor by the pyrolysis method.