• Journal of Advanced Marine Engineering and Technology
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• v.21 no.5
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• pp.503-511
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• 1997

In 3 phase induction motor control system, the speed control using the load torque observer becomes robust against disturbances by means of a feed-forward control of the estimated load torque component. In case of variation of inertia moment, the estimated load torque has error because the observer uses the nominal inertia to estimate the load torque. And so, it is difficult to obtain good speed control characteristics. This paper has two study target strategy. First, we executes feed-forward control with the load torque observer when motor inertia has nominal value and compare it with conventional PI con¬trol. The second strategy estimates inertia moment error using the load torque observer when inertia moment change. The proposed two strategy is confirmed through the computer simulations and the experimental implementations by TMS320C31 microprocessor.

• Journal of Korean Society of Rural Planning
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• v.12 no.2 s.31
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• pp.11-16
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• 2006

Value of rural amenity resources scattered in rural area is difficult to be assessed isolatedly. Rural Amenity Resources Map (RARM) is developed for assessing rural resources based on specific territory. In the developing process, knowledge based system is oriented because rural amenity is differed from personal feeling. Possible decision trees in RARM are developed in reviewing process of previous GIS based decision support systems, and information strategy planning is constructed for achieving goals such as rural tourism, down shifting, and rural investment.

• IE interfaces
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• v.16 no.3
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• pp.291-299
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• 2003

The managerial environment of automobile industry has been rapidly changing, mainly with the tighter standard of legal and environmental regulations, the pressure of cost reduction from the end-user, the various functional improvements of vehicles, and the globalization management. In order to survive in this complicate circumstances, the automakers have strongly pursued the mutual collaboration with the suppliers, especially tier-1, for the optimal selection of parts/materials and the assembly manufacturing processes of the new model development. They prepare the early involvement program for the suppliers during the conceptual design stage, and implement the win-win strategy of technology development activity, in order to improve the value creation. This study considers the strategic technology management of automotive steel sheets makers on the aspects of strategy, processes, human & physical resources, and organization structure. It also suggests the corporate strategies of steel mills, in order to obtain the technology competence.

• Journal of Power Electronics
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• v.15 no.6
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• pp.1559-1566
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• 2015

The brushless DC motor (BLDCM) has many advantages. As a result, it is widely used in electric vehicle (EV) drive systems. To improve the reliability of the motor control system, a position sensorless control strategy based on a sliding mode observer (SMO) is proposed. The global fast terminal sliding mode observer (GFTSMO) is proposed to enhance the control performance of the SMO control system. The advantages of the linear sliding mode and the nonsingular terminal sliding mode (NTSM) are combined in the control strategy. The convergence speed of the system state is enhanced. The motor commutation point is obtained with the observation of the back EMF, and the instantaneous torque value of the motor is calculated. Therefore, the position sensorless control of the BLDCM is realized. Experimental results show that the proposed control strategy can improve the convergence speed, dynamic characteristics and robustness of the system.

• Strategy21
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• s.38
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• pp.83-111
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• 2015

In these days, 1949 revolt of admirals has a variety of evaluations. In 1949, many people thought that revolt of admirals is simply disobedience to Secretary of Defense. Revolt of admirals was considered that Navy was defeated to Air force. At that time, many people didn't put too much meaning this case. But at long last, the confidential documents about revolt of admirals opened to the public. This historic event's value was re-evaluated. Many researches were progressed in USA, On the other hand only some researches were progressed in Korea. So I try to study this topic and discover another meaning. Then, I will apply this lesson that obtained through study to our Korea Navy.

• Korean Institute of Interior Design Journal
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• v.20 no.5
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• pp.105-113
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• 2011

Brand is a useful tool for modem people living under the age of the brand, to explain the information of their products by differentiating themselves from others. It also represents the value of company and plays a major role convincing customers. Even living space brands are no exception. According to the development of marketing management ability, living space brands require the new sales strategy to dominate the market over the business competition, and plan differently for a changing market environment. On such account, companies are commercializing the living space via establishing its brands. Thus the study will cover the living space differentiation strategies for promoting the brand images of respective construction companies and will strive to compare and analyze the differentiation strategy factors that construction firms are pursuing through case analysis framework. Moreover, it's objective focuses on materializing the strategies of living space in accordance to the brand application elements.

• Journal of Power Electronics
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• v.16 no.2
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• pp.769-777
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• 2016

This work focuses on current sharing between punch-through insulated gate bipolar transistors (IGBTs) connected in parallel and evaluates the mechanisms that allow overall current balancing. Two different control strategies are presented. These strategies are based on the modification of transistor gate-emitter control voltage V_GE by using an active gate driver circuit. The first strategy relies on the calculation of the average value of the current flowing through all parallel-connected IGBTs. The second strategy is proposed by the authors on the basis of a current cross reference control scheme. Finally, the simulation and experimental results of the application of the two current sharing control algorithms are presented.

• Journal of Power Electronics
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• v.13 no.4
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• pp.647-655
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• 2013

In this paper, an approach to reduce the common-mode voltage and to eliminate narrow pulse for implemented AC-DC matrix converters is presented. An improved space vector modulation (SVM) strategy is developed by replacing the zero space vectors with suitable pairs of active ones. Further, while considering the commutation time, the probability of narrow pulse in the conventional and proposed SVM methods are derived and compared. The advantages of the proposed scheme include: a 50% reduction in the peak value of the common-mode voltage; improved input and output performances; a reduction in the switching loss by a reduced number of switching commutations and a simplified implementation via software. Experimental results are presented to demonstrate the correctness of the theoretical analysis, as well as the feasibility of the proposed strategy.

• Asia pacific journal of information systems
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• v.10 no.1
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• pp.189-205
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• 2000

It is important to investigate into the critical success factors(CSFs) of the CIO system in order to formulate a successful introduction strategy of the system. In an effort to provide the strategy, this research attempts to identify the CSFs of the system in the organizations of the private and public sectors in Korea. A result from the analysis of data collected shows that most organizations in Korea have already adopted, or are planning to adopt, the CIO system, implying that the value of the system is well recognized. Another result suggests that the success of the CIO system necessitate the CIO's abilities to recommend adequate IT and to apply appropriate IT solutions for the organization.

• Proceedings of the KSME Conference
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• 2001.06b
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• pp.724-729
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• 2001

This paper discusses the composition of the theory of reinforcement learning, which is applied in real-time learning, and evolutionary strategy, which proves its the superiority in the finding of the optimal solution at the off-line learning method. The individuals are reduced in order to learn the evolutionary strategy in real-time, and new method that guarantee the convergence of evolutionary mutations are proposed. It possible to control the control object varied as time changes. As the state value of the control object is generated, applied evolutionary strategy each sampling time because the learning process of an estimation, selection, mutation in real-time. These algorithms can be applied, the people who do not have knowledge about the technical tuning of dynamic systems could design the controller or problems in which the characteristics of the system dynamics are slightly varied as time changes. In the future, studies are needed on the proof of the theory through experiments and the characteristic considerations of the robustness against the outside disturbances.