• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.4
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• pp.177-184
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• 2001

In this study, three most distinct types of general rigid connections are included in the modelling, with is implemented into a computer code. The cost, functions of connections are constructed by using the estimated unit cost of bolting, welding and connection-steel elements incorporating all the effect of materials, labor, and fabrication work. Bused on the recent developments of the reliability-based structural analysis and design as well as the extending knowledge on the probabilistic characteristics of load and resistances, the probability based design criteria have been successfully developed for many standards. Since the probabilistic characteristics depend highly on the local load and resistances, it is recognized to develop the design criterion compatible with domestic requirements. The existing optimum design methods, which are generally based on the structural theory and certain engineering experience, do not realistically consider the uncertainties of load and resistances and the basic reliability concepts.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.4
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• pp.109-120
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• 2001

Live load data were collected with a systematic manner from a survey of a refrigeration stores. Using the collected floor live load survey data, the basic statistics, a histogram of the uniformly distributed loads, and the equivalent uniformly distributed loads are computed for various structural members. Based on the above results, the maximum values of a combined live loads during the design life have been estimated and compared with current design live loads. The ultimate goals of this study are to develop probabilistic live load models to analyze survey data of domestic refrigeration stores, and to propose design live loads for structural types.

• Journal of the Korea institute for structural maintenance and inspection
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• v.1 no.1
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• pp.113-124
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• 1997

Based on the recent developments of the reliability-based structural analysis and design as well as the extending knowledge on the probabilistic characteristics of load and resistances, the probability based design criteria have been successfully developed for many standards. Since the probabilistic characteristics depend highly on the local load and resistances, it is recognized to develop the design criterion compatible with domestic requirements. The existing optimum design methods, which are generally based on the structural theory and certain engineering exprience, do not realistically consider the uncertainties of load and resistances and the basic reliability concepts. This study is directed to propose a optimum design based Expected Total Cost Minimization on two-way slab system which could possibly replace optimum design based traditional provisions of the current code, based on the AFOSM reliablity theory.

• Journal of Auto-vehicle Safety Association
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• v.6 no.1
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• pp.33-40
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• 2014

In this study the cylinder liner deformation which is one of the most influencing factors in a diesel engine oil consumption was performed by the finite element analysis on the basic designed structure consisting of the cylinder block, head and liners under the conditions of assembly, thermal and gas loads. Compared with a large number of other cylinder blocks showing remarkable harmonic orders of the liner distortion, results are excellent. Namely. the higher harmonic order amplitudes of the radial liner deformation amount to 1 ~ 2㎛ maximally. The main reason lies in the relatively large wall thickness of the liner which amounts to 8.2% of the bore diameter. Besides, a very stiff and symmetrical cylinder block design in combination with a bolt force introduction approximately 1.5mm below the block top deck have a further share on these results. Therefore excellent low oil consumption can be expected.

• Journal of Korean Society on Water Environment
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• v.26 no.5
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• pp.761-767
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• 2010

This study introduces a model of territorial analysis on Chungcheongnam-do Nonsan-chun valley area, which gives an example of a method of selecting the management area for non-point pollution source from land use to help eliminate its source. High discharge load per unit area signify high level of land ratio with high level of basic unit of development load (including factory sites, school sites, roadways), which mean that there are a significant level of urbanization. It is these areas with the examination of the water quality of the nearby river that should be considered as the management area for non-point pollution source. Thus, the management area for non-point pollution source should be sought in areas with high discharge load per unit area and high density of water pollution area. When level of drainage is high the pollution density level is relatively lower, and when the level of drainage is low the density level is relatively higher. The level of pollution from non-point pollution source is much lower with more water flowing through. The possible non-point pollution source areas that were selected with these standards were then examined with the distance from the river, the slope angle, land usage, elevation, BOD discharge density load, T-N discharge density load, T-P discharge density load, and were given a level one through five. Out of the possible areas Nonsan-si Yeonmu-eup Anshim-li was the densest area, and it was given level one. The level one area should be examined further with the field analysis to be selected as the actual management area for non-point pollution source.

• Journal of Ocean Engineering and Technology
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• v.3 no.2
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• pp.645-645
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• 1989

• Progress in Superconductivity and Cryogenics
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• v.8 no.4
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• pp.30-33
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• 2006

Several crucial issues are discussed in the design of cryogenic cooling system for high field magnets. This study is mainly motivated by our ongoing program to develop a 21 T Fourier Transform Ion Cyclotron Resonance Mass Spectrometer (FT-ICR MS). The magnets of this system will be built horizontally to accomplish the requirement of user friendliness and reliability, and the replenishment of cryogen will not be necessary by a closed-loop cooling concept. The initial cool-down and safety are basically considered in this paper. The effects of the helium II volume and the gap distance of the weight load relief valve (or safety valve) on the cool-down time and temperature rising during an off-normal state are discussed. The total amount of cryogenic cooling loads and the required helium flow rate during cool-down are also estimated by a relevant heat transfer analysis. The temperatures of cryogen-free radiation shield are finally determined from the refrigeration power of a cryocooler and the total cryogenic loads.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1395-1401
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• 2010

A paradigm shift in driving system of transportation vehicle from engine to electric motor is required as the problems on air pollution and drain of petroleum resource are on the rize. Moreover while it is possible to control the motor with variable frequency driver, the application of motor in various kinds of vehicles is spread rapidly. In the paper, the effective design method of IPMSM for EV and HEV by using equivalent magnetic circuit and finite element method (FEM) is suggested. First of all, load conditions of the application are calculated. And basic design process of IPMSM is proposed with two design point. Finally, in order to verify the proposed design process, it was compared with the basic design parameter and the FEM analysis results.

• Progress in Superconductivity and Cryogenics
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• v.14 no.4
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• pp.46-49
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• 2012

The selection of the temperature sensor in the cryogenic system depends on the temperature range, shape and accuracy. The accuracy of the temperature sensor is essential to improve the reliability of experiment. We have developed the variable temperature cryostat using a two-stage cryocooler. In order to reduce heat load, thermal shield is installed at the first stage with MLI (Multiple layer insulation). We have also developed the sensor holder calibrating more than twenty sensors at the same time for saving time and money. The system can calibrate sensor at variable temperature by controlling electric heater. In this paper, we present design and fabrication of variable temperature cryostat and representative result of Cernox sensor calibration.

• Progress in Superconductivity and Cryogenics
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• v.11 no.2
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• pp.41-43
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• 2009

The HTS power cable system of 3-phase 100-m class has been tested at the KEPCO's Gochang power testing center in Korea during 8,000 hours or more for investigating long-term operating performance. The system is rated 22.9kV, 1250A and is cooled with sub cooled liquid nitrogen. Several cooling performance tests such as cooling capacity, heat load, AC loss, temperature stability and thermal cycle were performed at operating temperature of 66.4K and several different temperatures.