• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.111-116
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• 2004

An experiment was carried out to confirm the validity of time series evaluation of supersonic mixing condition by using catalytic reaction on a platinum wire. Geseous hydrogen was injected parallel to supersonic freestream (M$\infty$ $\approx$ 1.81) from a slit injector, which was located at backward facing step. Time series condition of supersonic mixing was evaluated by using W-type probe which has a platinum wire and reference wire (nickel wire). The evaluation was by simultaneously measuring each electric circuit which kept the temperature of wire constant. Investigations were also conducted for helium, air and no secondary injectant cases to compare with the hydrogen injectant case. The results indicated that it was possible to measure the time series behavior of air and hydrogen supersonic mixing layer or coherent motion of turbulence by using this evaluation.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.1 no.1
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• pp.123-141
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• 1972

The Kosachalyo was the reference book which was composed of records collected about the procedures regulating the foreign relations or daily lives of the officials or the scholars, who had no official positions, in the Yi dynasty. The compilation work of the Kosachalyo was started from the date of the compilation of the original one by U sook-kwon (魚叔權) in the 9th year (1554) of King Myongjong (明宗). Su Myongung (徐明) revised and complemented the contents of the original one in full scale, named it as the Kosashinsu(攷事新書) in the 47th year(1771) of King Yongjo(英祖). In that period, the original Kosachalyo was revised and complemented twelve times and republished. Until now, it has been said that the original Kosachalyo had been suffered the revising or complementing works six times or nine times. But in this thesis it is assured that it was revised or complemented twelve times in the period from 1554 to 1771 upon the various historical documents.

• Journal of Communications and Networks
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• v.9 no.2
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• pp.177-184
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• 2007

Alamouti space-time code (STC) is a part of the UMTS-WCDMA standard. However, up to the best of our knowledge no exact closed-form outage and bit error probability (BEP) formulas for this famous code exists. Evaluating its performance through simulations is time-consuming and therefore, there should be analytical performance graphs to serve as a reference which are derived in this paper for coherently MPSK-modulated data. Additionally, analytical results take into account different channel fading levels from transmit antennas to receive ones.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.9
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• pp.500-505
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• 2003

The target of the ULTC(Under Load Tap Changer) control purpose is to minimize the operation number of the tap of the ULTC doing the error voltage which is the difference between the measured bus voltage End the reference bus voltage of the receiving end becomes less than the tolerance limits. The existing ULTC control method controls each ULTC considering only its bus voltage of the receiving end. However, this method did not cons der the coordinated control of the ULTCs of the system. In this paper, I proposed a coordinated control of the ULTC in :he loop power system using the Jacobian matrix. To show the validity of the proposed method, I made simulations for three cases: no action of the ULTC, the control of the ULTC by the existing control method, and the control of the ULTC by the coordinated control among the ULTCs of the system. The simulation result shows that the proposed method has more improvement of the operation of the ULTC than other methods.

• Journal of the Korean Home Economics Association
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• v.20 no.4
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• pp.169-176
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• 1982

This study attempts to explore and explain major socieconomic factors which determine the extent of rural consumers' external search behavior in cases of two product categories: electric appliances and clothing. For the purpose of this study, interviews were conducted with 201 home managers in four rural towns(Hwasun, Haenam, Naju, and Bulkyo) of South Cholla Province. On the whole, the hypotheses that socioeconomic status, age and the characteristics of region of rural consumers make significant differences in their shopping motivation and the extent of external search are generally supported in case of clothing. No substantial differences are found in case of electric appliances. This study suggests that the effective purchasing system and the providing of informative consumer information would be needed to rural consumers for their extensive search. It also suggests that psychological aspects and situational variables in addition to socioeconomic aspects presumably contribute to our understanding of search behavior.

• Journal of the Korea Institute of Military Science and Technology
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• v.15 no.2
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• pp.155-160
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• 2012

In this paper, a strip modeling method is developed for the acquisition of target positions in remote area and validated using the imagery of SPOT satellite. This method utilizes the parameters given in header files and constructs a camera model without ground control points. In most cases, the root mean squared error of check points is less than pixel size with one ground control point. The model error of reference image is evaluated using ground control points and used to remove the model error of target images acquired along the same satellite orbit, which enables one to calculate target positions in remote area where no ground control points are available.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.29-32
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• 2008

Cultural assets are subject to general elements of deterioration due to aging of materials and surrounding conditions over time and these elements do not influence structural safety. However, wood cracking(penetrative), disparity of joints, deformation of structure, damage by insects and ground subsidence as the elements of structural deterioration as well as slanting of building structure caused by composite elements exert serious impact on safety of cultural assets. Therefore, repair must be administered by deciding the appropriate time and investigating the status. However, there are no grounds for making such decisions because investigative data on cultural assets have not been organized analyzed and the results of investigation have not been established as database. There is also lack of objectified bases. Therefore, this study aimed to investigate organize elements of structural deterioration with reference to cultural assets of building structures in Seoul so that to use the results found as the basic data for preservation of cultural assets.

• Korean System Dynamics Review
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• v.12 no.4
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• pp.157-175
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• 2011

The purpose of this paper is to find out the effects of the gambler's fallacy bias on the supply chain. For this study, the simulation was based on a casual structure of the Beer Distribution Game from Sterman(2000)'s Business Dynamics and designed into 2 different models : the first model carries the exact same structure as the reference mentioned above and for the second model, the comparison model is used reflecting gambler's fallacy bias. Each model has 2 different demand patterns. The 4 cases of models was tested with 1,000 different random number seeds. The results for the simulation are following : In the aspect of the inventory and out of stock, the basic model resulted better than the comparison. However, in the bullwhip effect, the comparison model has less than the basic in terms of the level demand pattern. But there was no significant difference in the cycle demand.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.4
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• pp.99-106
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• 2008

Digital Terrain Elevation Data is a set of numerical values that represent the heights of the terrain surface. Terrain has several properties. Among them, roughness is the most widely used one because it gives very useful information to land-based or land-reference platform. There are several ways to measure roughness of terrain. But each of them has own flaws. Moreover, it is not enough to represent the uniqueness of the terrain only by the roughness. We need another metric to measure the actual uniqueness. In this paper, we propose an improved method to measure essential characteristics, uniqueness, of terrain. It gives not only the roughness but also the unevenness. The combination of them makes up the uniqueness. And it can be applied even if there is no pre-planned path on the terrain.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1524-1526
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• 2005

This paper describes the measurement and analysis of the basic line constants in PLC(Power Line Communication) in the residential building. An apartment is considered as one of the conventional residences to get the line constants in this paper and Agilent 4263B LCR Meter is used to measure the detailed values each area and the specific results and the averaged analysis data are shown in the tables. The measured results no different from the calculated values with using conventional formula due to the line arrangement neglected factors, complex permittivity, and etc. Also, this paper describes many kinds of lines and wiring figures of domestic construction. Finally, it is utilized with the analyzed line characteristics in frequency domain as a planning reference of PLC.