• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.2
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• pp.329-340
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• 1997

A passive control of interaction of condensation shock wave / boundary layer for reducing the strength of condensation shock was conducted experimentally in a 2.5 * 8 cm$^{2}$ indraft type supersonic wind tunnel. The effects of following factors on passive control were investigated: 1) the thickness of porous wall, 2) the diameter of porous hole, and 3) the orientation of porous hole. On the other hand, the location of nonequilibrium condensation region and condensation shock wave was controlled by regulation of the stagnation conditions. Surface static pressure measurements as well as Schlieren observations of the flow field were obtained, and their effects were compared with the results the cases of without passive control. It was found that thinner porous wall, smaller porous hole and FFH orientation for the same cavity size and porosity of 12% are more favourable than the cases of its opposite.

• The Journal of Industrial Distribution & Business
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• v.8 no.7
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• pp.13-20
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• 2017

Purpose - Performance appraisal has a significant influence on the development of low-carbon tourism distribution. Research design, data, and methodology - Data of this study are collected from 27 provinces (cities) of China. SBM-Malmquist model is used to measure the TFP and its dynamic changes of low-carbon tourism distribution; TOBIT model is used to discuss the factors of TFP of low-carbon tourism distribution. Results - The results show that, there are obvious differences among regional TFP of low-carbon tourism distribution, the average change tends to grow positively in general, and the western region grows fastest on average due to the improvement of technical efficiency and technical progress, while there are technical efficiency improvement but technical regresses in eastern and central regions. The economic scale, economic strength, structure of energy consumption, location quotient and government regulation have a significant positive effect on the TFP of low-carbon tourism; energy intensity, industrial structure and opening degree have a negative effect; investments in fixed assets, intensity of R&D fund and urbanization rate have no significant influence on the TFP of low-carbon tourism. Conclusions - Improving the productivity of low-carbon tourism and reducing regional differences are effective ways to develop low-carbon tourism and enhance tourism competitiveness.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.1
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• pp.217-224
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• 2003

The frost and mist in the windshield disturb the sight of driver and passengers especially in winter. This possibly leads to safety problems. In order to export automobiles to the countries of North America, the safety regulation requires the frost of selected area should be completely melted in 30 minutes. The defrost pattern and time for melting of frost are fully dependent on the flow and temperature field near the windshield. Furthermore, the flow and temperature field near the windshield are dependent on the air discharged from defrost nozzle. The present work has been done for understanding the flow features of the discharged air and internal flow within the nozzle duct. The three dimensional Navier-Stokes code was used for performing the generic A/C duct flow analysis. The present results were nearly coincided with experimental data. To perform the parametric study of the effectiveness of the number of guide vanes, the discharge angle and the location of nozzle were changed. The ratio of volume flow rate through defrost nozzle and side exit were compared to investigate the influence of parameters on the effectiveness of defrost nozzle. The velocity profiles and flow patterns of the defrost nozzle duct were also analyzed.

• Journal of the Society of Naval Architects of Korea
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• v.56 no.3
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• pp.263-272
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• 2019

The aim of this study is to develop a rapid calculation technique of the residual strength in order to prevent sequential events under grounding accidents. Very Large Crude-Oil Carrier (VLCC), Suezmax, and Aframax double hull oil tankers carrying large quantities of crude oil were selected for target structures. The rock geometries are chosen from the published regulation by Marine Pollution Treaty (MARPOL) of the International Maritime Organization (IMO). Oceanic rocks as the most frequently encountered obstruction with ships are applied in this work. Damage condition was predicted using ALPS/HULL program based on grounding scenario with selected parameters, i.e. depth of penetration, damage location and tanker type. The results of the scenarios are quantified to form an empirical formula which can evaluate the residual strength. The proposed formula is validated by applying a series of random grounding scenarios.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.35 no.5
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• pp.431-438
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• 2017

The information management system for urban planning, urban management and related decision making is increasing an importance in recent years. Especially, the information about 3D buildings in urban area is necessary for urban management related precise location based service. However, it takes a lot of time, effort, and costs to produce 3D modeling data of buildings. These problems have been found in many studies, but the research to solve these problems is still necessary. In this study, we have tested an efficient 3D modeling method of building to solve these problems. SketchUp was used to test 3D modeling methods with OSM(OpenStreetMap) data. The other 3D modeling method using a digital map was tested. The 3D modeling of building data was efficient using PlaceMaker, which can use OSM data. In addition, modeling was possible through simple editing of the digital map and automatic building generation. The efficiency of the research results is presented by comparing with the traditional method based on the regulation and the stadard man power issued by Korean government. These two 3D modeling methods of building tested through the study can be used as basic data for related research and work. Additional studies should be conducted to improve the accuracy of the building model and determine how to obtain height data efficiently.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.214-218
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• 2008

Because on the high-tension underground distribution line of an electric railway high voltage XLPE Cable two or three circuits between railway stations with a standard as receiving transformer facilities are established at a $30km{\sim}50km$ interval, reactive power in which the phase of a current is larger than that of a voltage is supplied when trains are not working, so when there are no loading or low loading as night. Due to the long-distance trend of the underground distribution system on an alternating current railway distribution line, the terminal voltage of a transformer is over the standard voltage, and after all, commercial cycle overvoltage is continued. To solve this problem, the shunt reactor is installed in middle of power distribution lines to maintain receiver voltage meted under the allowance regulation through control of the reactive power. Also, in case that the thickness of single cable is over $60mm^2$ and length of line is about over 30km, a circuit breaker is broken by shorting shunt ability of charging current in excess of shunt current(31.5A.rms). Therefore, this thesis presents installing the location of shunt reactor for quantitative analysis by using optimum algorism for compensation and control of the charging current.

• Journal of the Korean Solar Energy Society
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• v.26 no.1
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• pp.99-104
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• 2006

This paper presents an analysis of heating energy for apartment houses in apartment building, paying special attention on the effect of pilotis which is increasing recently. A four-zone model composed of one conditioned and three unconditioned space is developed in this study. IES VE is adopted to estimate heating energy. Especially, we used Apache module for a heating energy calculated. The predicted result shows fairly good agreements with the available measured data and simulation data. Heating energy needed for an apartment located on the pilotis floors is far greater compared with the case of intermediate floors. Insulation thickness of walls, floors and underground structure appears to be a dominant factor affecting heating energy, which leads to needs of revision of the related regulation. It is finally concluded that the location dependent, severe imbalance in heating energy should be improved and reflected in the policy making process and the design standards.

• Journal of Auto-vehicle Safety Association
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• v.15 no.4
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• pp.39-47
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• 2023

Research on the safety of autonomous vehicle is being conducted in various countries, including the European Union, and computer simulation techniques so called 'Virtual Tool Chain' are mainly used. As part of the crash safety study of autonomous vehicle, 25 car to car collision scenarios were provided as a result of a real accident-based accident reproduction analysis study conducted by a domestic research institution, and a vehicle crash analysis was performed using the FE car to car model of the Honda Accord. In order to analyze the results of the car to car simulation and to construct a database, major crash parameters were selected as impact speed, angle, location, and overlap, and a method of defining them in an indexed form was presented. In order to compare the crash severity of each scenario, a value obtained by integrating the resultant acceleration measured by the ACU of the vehicle was applied. The equivalent collision test mode was derived by comparing the crash severity of the regulation test mode, 30 deg rigid barrier mode, in the same way.

• Applied Biological Chemistry
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• v.34 no.1
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• pp.43-48
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• 1991

New quinoline compounds were designed, synthesized, and examined with submitochondria. Most compounds showed high activity against NADH-ubiquinone oxidoreductase. Inhibition activity was mainly affected by the length of the lipophilic part, regardless of bulkiness or location of a phenyl group in the side chain. The $\beta-methyl$ group was demons)rated to be the optimal functionality on the nuclei of the quinoline derivatives so 4hat either deletion or insertion of a methylene on the group eliminated its activity.

• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.330-333
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• 2002

Even if the train of subway starts in a certain interval from the origin according to the operation plan. as the number of passenger gets increased during operation. the boarding and getting-off time will increase, and the temporary breakdown happens to the system of train during operation, causing the delay from the operation plan. this leads to the vicious circle of train operation. making the interval of train operation irregular in downtown especially. To solve this problem, we propose the method of advanced algorithm by the actual data relating to the train operation including operation time required between stations, distance between stations. capability of train, and the dwelling time, location and distance between the preceding train and next one. The central train control system adjusts the dwelling time at each station in order to recover the delayed time, and increase the operation speed at the each station. As control algorithm is applied the dwelling time and to increase the speed, the train maintains certain interval after certain amount of time passes.