• Journal of Institute of Control, Robotics and Systems
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• v.7 no.4
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• pp.295-303
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• 2001

The demand for steam generators is increasing in industrial systems in which the design strategy should be implemented for safe and efficient operation of steam generators. It is, however, difficult to design a controller by the conventional method because of the nonlinear dynamics of the steam generator and influences by the set value of disturbance. This paper presents an automatic parameter optimization technique for a multivariable fuzzy controller using evolutionary strategy, At first, we use the steady state information such as a steady state gain matrix(SSGM) and a relative gain matrix(RGM). We can obtain much information on the control inputs and the outputs of the boiler-turbine system from the matrices. In order to determine the structure of the controller by using RGM and SSGM, the fuzzy rules are trained by evolutionary strategy. The good performance of the proposed multivariable fuzzy controller is verified through simulations.

• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.411-413
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• 2001

This paper discusses on an optimal bidding strategy of a generator in a competitive electricity spot market using the information of predicted spot price with some assumptions. Optimal bidding strategy of a generator is derived by solving a profit-maximizing optimization problem with a constraint where the forecasted spot price is treated as a constant value. The main advantage of this methodology is that the optimal bidding strategy of each generator can be obtained independently where the gaming characteristics of generators are merged into the forecasted spot price.

• Proceedings of the Safety Management and Science Conference
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• 2003.11a
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• pp.105-111
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• 2003

This paper examines to focus on General Strategy of e-logistics activity for SCM(Supply Chain Management) Build-up, especially the field service logistics Integration. And this research analyzes the case study (Business of Strategy Group Unit) Survey) involving effective logistics management that leads customer satisfaction, seeking to find out the key elements of competitive policy. Because problems arise from the differences between their goals and structures, which cause each sied to feel vulneralbe to opportunism or shirking of responsibilities by the other. The goal of a logistics system is to ensure that every family planning client always receives the contraceptives partner wants, and that they are in good condition and have not expired. In order to select, procure, and distribute the right Quantities of the right contraceptives, managers of the logistics system must keep informed of the rates of use of each contraceptive and of the Quantity of available supplies. As a result, We propose that a firm's e-logistics strategy is an important locus innovation and a crucial source of value creation for the firm its suppliers, partners, and customers.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.4
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• pp.402-409
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• 1999

Variable structure control law is well known to be a robust control algorithm and evolution strategy is used as an effective search algorithm in optimization problems. In this paper, we propose a variable structure controller with time-varying switching surface. We calculate the maximum value of seitching surface gradient that is of the 3rd order polynomial form. Evolution strategy is used to optimize the parameters of the switching surface gradient. Finally, the proposed method is applied to position tracking control for BLDC motor. Experimental results show that the proposed method is more useful than the conventional variable structure controller.

• Journal of Power Electronics
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• v.13 no.3
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• pp.479-486
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• 2013

This paper presents a control strategy for distributed systems, which can be used in islanded microgrids. The control strategy is based on the droop method, which uses locally measured feedback to achieve load current sharing. Instead of the traditional droop method, an improved one is implemented. A virtual inductor in the synchronous frame for three-phase inverters is proposed to deal with the coupling of the frequency and the amplitude related to the active and reactive power. Compared with the traditional virtual inductor, the proposed virtual inductor is not affected by high frequency noises because it avoids differential calculations. A model is given for the distributed generation system, which is beneficial for the design of the droop coefficients and the value of the virtual inductor. The effectiveness of the proposed control strategy is verified by simulation and experiment results.

• Proceedings of the KIPE Conference
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• 2015.07a
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• pp.355-356
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• 2015

This paper proposes a control strategy of total output power ripple cancellation for both of Machine-Side Converter (MSC) and Grid-Side Converter (GSC) in a DFIG under unbalanced grid conditions. The proposed control strategy for the MSC is the zero torque ripple control algorithm with an enhanced LVRT capability. The control algorithm for the MSC exhibits reduced torque pulsation in steady-state unbalanced grid conditions. In addition, this control algorithm also minimizes a peak value of rotor current in transient unbalanced grid conditions. The total output power ripple cancellation control algorithm is adopted in the GSC. The total output power ripple cancellation is achieved by nullifying the oscillating component of the total output active and reactive power at the summing point of stator and rotor of DFIG. The proposed control strategy for the GSC reduces the output power oscillation leading to the improved quality of wind farms output.

• Journal of the Korea Safety Management & Science
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• v.5 no.4
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• pp.117-130
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• 2003

This paper examines to focus on General Strategy of e-logistics activity for SCM(Supply Chain Management) Build-up, especially the field service logistics Integration. And this research analyzes the case study(Business of Strategy Group Unit) Survey) involving effective logistics management that leads customer satisfaction, seeking to find out the key elements of competitive policy. Because problems arise from the differences between their goals and structures, which cause each sied to feel vulneralbe to opportunism or shirking of responsibilities by the other. The goal of a logistics system is to ensure that every family planning client always receives the contraceptives partner wants, and that they are in good condition and have not expired. In order to select, procure, and distribute the right quantities of the right contraceptives, managers of the logistics system must keep informed of the rates of use of each contraceptive and of the quantity of available supplies. As a result, We propose that a firm's e-logistics strategy is an important locus innovation and a crucial source of value creation for the firm its suppliers, partners, and customers.

• Journal of Distribution Science
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• v.12 no.8
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• pp.31-42
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• 2014

Purpose - Recently, a variety of activities for practicing the continuing management of domestic and foreign companies have been conducted and further, corporate social responsibility for maximizing the value of stakeholders such as customers, cooperative companies, and the local community emerges as a key business strategy. Accordingly, the issue of whether corporate image and customer value through corporate social responsibility activities positively affect customer loyalty and customer attitude is investigated in this study. Research design, data, and methodology - Corporate social responsibility activities are classified into legal and moral activities, environmental protection activities, economic activities, and community service activities; further, customer values are classified into emotional value, functional value, and social value, to determine the parameters. In addition, the strategic approach direction of social responsibility activities is justified as a strategy for effectively achieving the expected results that corporations seek by proving the effect of these parameters on customer loyalty. Results - The study results can be summarized as follows. First, legal and moral activities, environmental protection activities, economic activities, and community service activities are four types of CSR activities affecting meaningful improvements in corporate image. Second, legal and moral activities affect factors that meaningfully improve customer value, including factors such as emotional value, functional value, and social value, while environmental protection activities affect improvements in the factor of social value only. Third, corporate image affects meaningful improvements in customer value. Fourth, corporate image affects improvements in customer loyalty positively. Fifth, the three factors of customer value, that is, emotional value, functional value, and social value affect meaningful improvements in customer loyalty. Sixth, customer value acts to partly mediate the effect of companies' CSR activities on customer loyalty. As shown in the study results above, it was verified that CSR activities affect meaningful improvements in corporate image and customer value and, in turn, corporate image and customer value affect meaningful improvements in customer loyalty. In addition, it was verified that customer value acts to partly mediate the effects of companies' CSR activities on customer value. Conclusions - Accordingly, the results of this study suggests as follows. First, it was clearly verified that customers' recognition of CSR efforts has a positive effect on corporate image, customer value, and loyalty because CSR activities improve the relationships between customers and corporations by providing customers with value. Second, it was suggested that corporations implement social contribution activities strategically according to the theory that the higher the rate of CSR activities, the better the corporate image and repurchase intention would be, which is a theory verified through practical analysis. Corporations should do this by constructing positive relationships from the value perceived by customers. To summarize the study results in a brief manner, it is suggested by the results of the study that a corporation should conduct CSR more actively to make customers recognize the positive image of their products and services.

• Journal of Intelligence and Information Systems
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• v.21 no.2
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• pp.151-171
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• 2015

This study examined the concepts of the Internet of Things(IoT), the major issue and IoT trend in the domestic and international market. also reviewed the advent of IoT era which caused a 'Paradigm Shift'. This study proposed a solution for the appropriate corresponding strategy in terms of Enterprise. Global competition began in the IoT market. So, Businesses to be competitive and responsive, the government's efforts, as well as the efforts of companies themselves is needed. In particular, in order to cope with the dynamic environment appropriately, faster and more efficient strategy is required. In other words, proposed a management strategy that can respond the IoT competitive era on tipping point through the vision of paradigm shift. We forecasted and proposed the emergence of paradigm shift through a comparative analysis of past management paradigm and IoT management paradigm as follow; I) Knowledge & learning oriented management, II) Technology & innovation oriented management, III) Demand driven management, IV) Global collaboration management. The Knowledge & learning oriented management paradigm is expected to be a new management paradigm due to the development of IT technology development and information processing technology. In addition to the rapid development such as IT infrastructure and processing of data, storage, knowledge sharing and learning has become more important. Currently Hardware-oriented management paradigm will be changed to the software-oriented paradigm. In particular, the software and platform market is a key component of the IoT ecosystem, has been estimated to be led by Technology & innovation oriented management. In 2011, Gartner announced the concept of "Demand-Driven Value Networks(DDVN)", DDVN emphasizes value of the whole of the network. Therefore, Demand driven management paradigm is creating demand for advanced process, not the process corresponding to the demand simply. Global collaboration management paradigm create the value creation through the fusion between technology, between countries, between industries. In particular, cooperation between enterprises that has financial resources and brand power and venture companies with creative ideas and technical will generate positive synergies. Through this, The large enterprises and small companies that can be win-win environment would be built. Cope with the a paradigm shift and to establish a management strategy of Enterprise process, this study utilized the 'RTE cyclone model' which proposed by Gartner. RTE concept consists of three stages, Lead, Operate, Manage. The Lead stage is utilizing capital to strengthen the business competitiveness. This stages has the goal of linking to external stimuli strategy development, also Execute the business strategy of the company for capital and investment activities and environmental changes. Manege stage is to respond appropriately to threats and internalize the goals of the enterprise. Operate stage proceeds to action for increasing the efficiency of the services across the enterprise, also achieve the integration and simplification of the process, with real-time data capture. RTE(Real Time Enterprise) concept has the value for practical use with the management strategy. Appropriately applied in this study, we propose a 'IoT-RTE Cyclone model' which emphasizes the agility of the enterprise. In addition, based on the real-time monitoring, analysis, act through IT and IoT technology. 'IoT-RTE Cyclone model' that could integrate the business processes of the enterprise each sector and support the overall service. therefore the model be used as an effective response strategy for Enterprise. In particular, IoT-RTE Cyclone Model is to respond to external events, waste elements are removed according to the process is repeated. Therefore, it is possible to model the operation of the process more efficient and agile. This IoT-RTE Cyclone Model can be used as an effective response strategy of the enterprise in terms of IoT era of rapidly changing because it supports the overall service of the enterprise. When this model leverages a collaborative system among enterprises it expects breakthrough cost savings through competitiveness, global lead time, minimizing duplication.

• Journal of Information Technology Applications and Management
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• v.12 no.4
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• pp.105-121
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• 2005

Ubiquitous computing(UC) is an emerging paradigm. Its arrival as a mainstream is expected to trigger innovative UC-driven business models (UCBMs). Currently, there is no Parsimonious methodology to analyze and provide diagnostics for UCBMs. With this research, we propose a analytical architecture that enables the assessment of an UCBM in its structural strengths and weaknesses. With value logic as the cornerstone, the architecture is composed of value actors, value assets, value context, business value Propositions, customer value propositions, value creation logics, and value assumptions. Dimensional variables are initially Identified based on the review of business model literature. Then, their significance is empirically examined through 14 UCBM scenarios, and variables that are expected to Play an important role in the UCBM assessment are decided. Finally, by analyzing the scenarios in terms of the dimensional variables, we attempted to summarize general characteristics of emerging UCBMs.