• Proceedings of the KSRS Conference
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• v.1
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• pp.56-59
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• 2006

In this paper, Korea's first geostationary Communication, Ocean and Meteorological Satellte(COMS) program is introduced. COMS program is one of the Korea National Space Programs to develop and operate a pure civilian satellite of practical-use for the compound missions of meteorological observation and ocean monitoring, and space test of experimentally developed communication payload on the geostationary orbit. The target launch of COMS is scheduled at the end of 2008. COMS program is international cooperation program between KARI and ASTRIUM SAS and funded by Korean Government. COMS satellite is a hybrid satellite in the geostationary orbit, which accommodates multiple payloads of MI(Meteorological Imager), GOCI(Geostationary Ocean Color Imager), and the Ka band Satellite Communication Payload into a single spacecraft platform. The MI mission is to continuously extract meteorological products with high resolution and multi-spectral imager, to detect special weather such as storm, flood, yellow sand, and to extract data on long-term change of sea surface temperature and cloud. The GOCI mission aims at monitoring of marine environments around Korean peninsula, production of fishery information (Chlorophyll, etc.), and monitoring of long-term/short-term change of marine ecosystem. The goals of the Ka band satellite communication mission are to in-orbit verify the performances of advanced communication technologies and to experiment wide-band multi-media communication service mandatory.

• Journal of Korean Tunnelling and Underground Space Association
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• v.2 no.2
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• pp.41-49
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• 2000

Rock Mass Rating has been widely applied to the underground tunnel excavation and many other practical problems in rock engineering. However, Rock Mass Rating is hard, even by the experts of tunnel assessment owing to lack of investigation system. In this study, using multivariate analysis we presented rock mass rating system that is objective and easy to use. The constituents of RMR are decided to RQD, condition of discontinuities, groundwater conditions, intact rock strength, orientation of discontinuities, spacing of discontinuities in important order. In each step, we proposed the best multiple regression model for RMR system.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.5
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• pp.70-78
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• 2003

From the viewpoint of the importance of the division theory based on topography(pyungsu) derived from the uniqueness in topography, not to mention of the function of ridge in ruban areas, the destroy of ridges should be prevented from the development of hill areas. This study intends to propose the basic concepts and principles to protect the ridge axis with green in open space and landscape planning. The main results are summarized as follows : First, eco-bridge across the ridges will be connected for the purpose of ecosystem restoration. Second, the protection and restoration of green ridge axis can be completed by Green Structure Plan which has principles and standards such as. - layout of development axis and establishment of rules on preservation - the practical use of various preservation methods and the standards suitable to the methods - laying down the standards of restoration according to the height from ground level - the application of zoning such as height district and urban design for preservation Finally, the design of implementation tools must be needed for protection and restoration.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.6
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• pp.19-25
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• 2008

Selective Catalytic Reduction is effective in the reduction of NOx emission. This research focused to evaluate the performance of a urea-SCR system and was conducted in two procedures. One is SCR reactor test using model gas in order to provide an optimal injection condition itself. In this step, some parametric study on emission temperature, space velocity, aspect ratio and the formation of urea spray were made by using flow visualization and Computation Fluid Dynamics techniques. The basic simulation results contributed in determining the layout for an actual engine test. The other is an engine performance and emission test. The urea injector was placed at the opposite direction of exhaust gases emitted into an exhaust duct and an optimal amount of a reducing agent is estimated accurately under different engine loads and speeds. Furthermore, the variation of NOx emission and applied amount of urea was investigated in terms of modes under the condition of with and without SCR, and other emissions such as PM, CO and NMHC were evaluated quantitatively as well. This research may provide fundamental data for the practical use of urea-SCR in future.

• Communications for Statistical Applications and Methods
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• v.24 no.2
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• pp.143-154
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• 2017

A variable selection method based on probabilistic principal component analysis (PCA) using penalized likelihood method is proposed. The proposed method is a two-step variable reduction method. The first step is based on the probabilistic principal component idea to identify principle components. The penalty function is used to identify important variables in each component. We then build a model on the original data space instead of building on the rotated data space through latent variables (principal components) because the proposed method achieves the goal of dimension reduction through identifying important observed variables. Consequently, the proposed method is of more practical use. The proposed estimators perform as the oracle procedure and are root-n consistent with a proper choice of regularization parameters. The proposed method can be successfully applied to high-dimensional PCA problems with a relatively large portion of irrelevant variables included in the data set. It is straightforward to extend our likelihood method in handling problems with missing observations using EM algorithms. Further, it could be effectively applied in cases where some data vectors exhibit one or more missing values at random.

• Journal of Astronomy and Space Sciences
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• v.23 no.1
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• pp.19-28
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• 2006

The noise temperature of existing millimeter-wave receivers is already within two or three times quantum noise limit. One of practical ways to increase the observation speed of single dish radio telescope without longer integration time is use of multi-beam focal plane array receiver as demonstrated in several large single dish radio telescopes. In this context the TRAO (Taeduk Radio Astronomy Observatory), which operates a 143n Cassegrain radio telescope, is planning to develop a 4 x 4 beams focal plane array SIS receiver system for 86-115 GHz band. Even though millimeter-wave HEMT LNA-based receivers approach the noise temperature comparable to the SIS receiver at W-band, it is believed that the receiver based on SIS mixer seems to offer a bit more advantages. The critical part of the multi-beam array receiver will be sideband separating SIS mixers. Employing such a type of SIS mixer makes it possible to simplify the quasi-optics of receiver. Otherwise, an SSB filter should be used in front of the mixer or some sophisticated post-processing of observation data is needed. In this paper we will present a preliminary design concept and components needed for the development of a new 3 mm band multi-beam focal plane array receiver.

• Journal of the Korean Institute of Rural Architecture
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• v.10 no.4
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• pp.1-8
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• 2008

The policy that do so the Geritol generation with advanced age generation's increase may be not estranged and can human down life is necessary times. The Medical treatment and welfare service is essential, and the aged support domiciliary care facility in the rudiments step more expand must. It is real condition that Kangwon-do's number of closed school appears by many things thirdly in whole country and the post management countermeasure is urgent. Because this research chooses the closed school by way to solve the closed school problem that happen by the child of school age decrease the farming and fishing villages or small city and the shortage problem of old people's welfare facilities by population graying at the same time. There is the purpose to grope practical use the possibility of local closed school as welfare center for the old who stay at home present remodeling to welfare facilities for the old man. Keeping the structure condition of a closed school maximum, the welfare center for the old who stay at home by remodeling a closed school ultimately proposed.

• Journal of Power Electronics
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• v.14 no.5
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• pp.1038-1046
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• 2014

Lithium-ion batteries are widely used in hybrid and pure electric vehicles. State-of-charge (SOC) estimation is a fundamental issue in vehicle power train control and battery management systems. This study proposes a novel model-based SOC estimation method that applies closed-loop state observer theory and a comprehensive battery model. The state-space model of lithium-ion battery is developed based on a three-order resistor-capacitor equivalent circuit model. The least square algorithm is used to identify model parameters. A multi-state closed-loop state observer is designed to predict the open-circuit voltage (OCV) of a battery based on the battery state-space model. Battery SOC can then be estimated based on the corresponding relationship between battery OCV and SOC. Finally, practical driving tests that use two types of typical driving cycle are performed to verify the proposed SOC estimation method. Test results prove that the proposed estimation method is reasonably accurate and exhibits accuracy in estimating SOC within 2% under different driving cycles.

• KIEAE Journal
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• v.14 no.5
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• pp.29-38
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• 2014

The Purpose of this study is to analyze the investigation of consumer's consciousness for Han-Ok construction of community facilities in an apartment housing. The contents of this study were largely composed of two parts; First was about concept and type of 'New Han-Ok type' public building. Second was about consciousness for Han-Ok construction of community facilities in an apartment housing. The result to this study is as following: 1) the concept of 'New Han-Ok type' public building should not only be defined in terms of cultural property or Han-Ok experience facilities but daily life and practical community. 2) the consciousness for Han-Ok construction of community facilities in an apartment housing was recognized affirmatively more than 75.9%. 3) the strengths of 'New Han-Ok type' public building was as following: daycare centers & small libraries & management office-use of eco materials, senior centers-traditional maintenance, community center-ease of daylight and ventilation. 4) Weaknesses of 'New Han-Ok type' public building was as following: daycare centers-security problem, senior centers-inconvenience of space, community facilities-inconvenience of facilities, small libraries-lack of storage space, management office-inconvenience of moving line. The conscious research for 'New Han-Ok type' public building should succeed for vitalizing for Han-Ok.

• IE interfaces
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• v.24 no.1
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• pp.78-86
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• 2011

To mitigate space restriction and to raise productivity, some shipbuilding companies use floating-docks on the sea instead of dry-docks on the land. In that case, a floating-crane that can lift very heavy objects (up to 3,600 tons) is used to handle the blocks which are the basic units in shipbuilding processes, and so, very large blocks (these are called the mega-blocks) can be used to build a ship. But, because these mega-blocks can be made only in the area near the floating-dock and beside the sea, the space is very important resource for the process. Therefore, our problem is to make an efficient spatial schedule for the mega-block assembly yard. First of all, we formulate this situation into a mathematical model and find optimal solution for a small problem using a commercial optimization software. But, the software could not give optimal solutions for practical sized problems in a reasonable time, and so we propose a GA-based heuristic algorithm. Through a numerical experiment, finally, we show that the spatial scheduling algorithm can provide a very good performance.