• Communications for Statistical Applications and Methods
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• v.8 no.2
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• pp.507-514
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• 2001

In recent years, the development and the embodiment of information analysis system has been sprightly carried out in several fields of study. In this study, as and extension of these studies, we develop a system for multivariate analysis which might be widely used in social and natural sciences. This multivariate analysis system is developed by using multivariate analysis procedures in SAS/STAT software. Also, the system supply users with he environment of GUI(Graphical User Interface), which is constructed with AF(application frame) and SCL(screen control language) of SAS software, in order to help users to use the system with easy.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.1004-1009
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• 2002

There are four servo systems in a DVD drive such as a focus servo system, a tracking servo system, a sled servo system and a spindle servo system. Focus servo system maintains relative distance between lens and disk. In this paper, two plant models for the focus servo system will be presented. One of them is conventional and the other is newly developed. Focus error signal between lens and disk is detected using LDV 2 beam method. The system is observable and all states are estimated. Full states feedback controller and minimum order observed are designed using those states. Impulse responses are simulated. And experiment is performed to compare with responses of conventional model.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.6
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• pp.546-554
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• 2010

The paper deals with the structural analysis and vibration test for the scaffolding system of LNG cargo containment. The eight-stories scaffolding system has telescopic area, working area, coner area and storage area in real system. In the structural analysis, the maximum displacement and stress of the each floor for the scaffolding system are investigated by finite element method. In the vibrational analysis, the natural frequencies and mode shapes for 8-stories scaffolding system of the LNG cargo containment are investigated. In order to compare theoretical natural frequencies with experimental ones, small size of 2-step scaffolding structure is used, and the theoretical results for natural frequency have a good agreement with experimental ones.

• International Journal of Safety
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• v.6 no.2
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• pp.38-42
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• 2007

As railway signaling system is computerized, the significance on safety demonstration and assessment has been increased. Therefore, railway signaling system should reflect the needs for safety assessment technique. Various studies on safety assessment technique for railway signaling have been made in Europe and standardization of the requirements for safety acceptance has been initiated by IEC. In order to develop and establish the safety assessment techniques for railway signaling in Korea, we try to review safety assessment activities for signaling system via reviewing relevant case studies and consulting with experts. And also we propose the safety assessment activity/methodology for Korean railway signaling system.

• Journal of the Korean Society of Industry Convergence
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• v.3 no.2
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• pp.141-147
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• 2000

The nonlinear response statistics of an autoparameteric system under broad-band random excitation is investigated. The specific system examined is a vibration absorber system with internal resonance, which is known to be a good model for a variety of engineering systems, including ship motions with nonlinear coupling between pitching and rolling motions. The Fokker-Planck equations is used to generate a general first-order differential equation in the dynamic moment of response coordinates. By means of the Gaussian closure method the dynamic moment equations for the random responses of the system are reduced to a system of autonomous ordinary differential equations. The jump phenomenon was found by Gaussian closure method under random excitation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.25-26
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• 2011

The objective of this study is to develop the prototype system for microwave heating in a manufacture process of alkali activated Hwangtoh binder as replacement materials for the cement in concrete. In order to achieve this, four research phases are carried out as follows: 1) establishment of a system concept 2) deduction of a system element 3) design of the entire system 4) making of the prototype system for microwave heating.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.8
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• pp.145-162
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• 1997

Performance appraisal system is to evaluate employee' work performance, work ability and work attitude. It becomes a important foundation of personnel management. This system's goal is to accomplish employee ability development. The purpose of this study is to make some contributions in order to efficient performance appraisal system of hotels by analyzing the problems of current performance appraisal system. The suggestions for efficient performance appraisal system are as follows: 1. Performance appraisal by job analysis. 2. Though evaluators' training for objective assessment. 3. The assistance system of appraisal results for employees. 4. Magnifying use of appraisal results. 5. Object management strategy by using self-rating.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.2
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• pp.218-228
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• 2003

A hydraulic system is modeled as the second order differential equation with uncertain system parameters and disturbance composed of modeling errors. To Position the load of the hydraulic system to a desired point. the servo valve of the hydraulic system is controlled. As a control scheme. a global sliding mode control(GSMC) is Proposed Since the servo valve has a torque limit. the GSMC is designed to coordinate the position of the load along the minimum time trajectory within the torque limit. The Proposed control scheme can be designed with ranges of parametric uncertainties and specified torque limits. By the proposed control scheme, the closed form solution of the arriving time at the desired position can be estimated.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.2198-2204
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• 2003

In order to make a match of the insufficient direct solar radiation, in this study, the target output is lowered to 9 kW smaller than 25 kW in former studies. It is also necessary to match the collector/receiver with engine/generator systems to accomplish the power level of a system. The simulation analyses of a dish solar power system with stirling engine are totally carried out to predict the system performance with the designed values. In addition, an influence of direct solar radiation on system performance and operation control is discussed in simulation. It is found that the diameter of concentrator could be made small to 8 m regardless of slope errors with 2.5 and 5.0 mrad radiation, and the operation range of mean pressure control. is wide even if the direct solar radiation is a quit low.

• Korean Journal of Organic Agriculture
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• v.19 no.4
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• pp.463-474
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• 2011

The objectives of this study were to establish of resource cycling agricultural system focused on farmer's organization. Case is selected as the farming corporation for the regional agriculture considering the amount of sowing by-products and livestock by-products generated. As a result, generation of fertilizer ingredient depend on feces and urine of Korean native cattle is estimated nitrogen 7.7 ton, phosphoric acid 2.9 ton, and potassium 4.9 ton. On the other hand, generation of fertilizer ingredient demand in cultivated acreage is estimated nitrogen 42.4 ton, phosphoric acid 14.3 ton, and potassium 17.0 ton. Therefore, optimum livestock numbers is estimated 1,867 cattle and it means 1,468 cattle can be raise additionally. In order to complete the resource cycling agricultural system, it should be establish nutrient management system at all of organization level and achieve improvements in regional resource supply. Both economic value of organic fertilizer and the resource cycling system linked market system is considered to develop resource cycling level.