• Journal of The Korean Digital Architecture Interior Association
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• v.11 no.2
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• pp.83-92
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• 2011

The purpose of this study is to propose strategies for reducing greenhouse gas emissions on urban areas. This study is made up GHG emission estimation and emission prospect methods, setting of GHG reduction target, GHG reduction plan formulation and feasibility assessment. The significance of this study is as follows. First, this study provides the local government for the overall frame of low carbon strategies. Second, this study contribute to establishment of GHG emission reduction strategies in the local autonomy by providing GHG emission estimation and setting reduction target which is essential elements of reduction strategy. Third, we organize a reduction element for low carbon city embodiment and showed the way to assessment the reduction effect of these elements quantitatively.

• Journal of Power Electronics
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• v.16 no.3
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• pp.1036-1045
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• 2016

This paper presents a novel control strategy for passive output filter reduction using an active output filter. The proposed method achieves the dual-function of regulating the output voltage ripple and output voltage variation during load transients. The novel control strategy allows traditional simple voltage controllers to be used, without requiring the expensive current sensors and complex controllers used in conventional approaches. The proposed method is verified with results from a 125-W forward converter.

• Nuclear Engineering and Technology
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• v.49 no.3
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• pp.525-533
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• 2017

A new concept termed the Innovative Nuclear Power Plant Building Arrangement (INBA) strategy is a new nuclear power plant building arrangement method which encompasses upfront consideration of more efficient decommissioning. Although existing decommissioning strategies such as immediate dismantling and differed dismantling has the advantage of either early site restoration or radioactive decommissioning waste reduction, the INBA strategy has the advantages of both strategies. In this research paper, the concept and the implementation method of the INBA strategy will be described. Two primary benefits will be further described: (1) early site restoration; and (2) radioactive waste reduction. Several other potential benefits will also be identified. For the estimation of economic benefit, the INBA strategy, with two primary benefits, will be compared with the immediate dismantling strategy. The effect of a short life cycle nuclear power plant in combination with the INBA strategy will be reviewed. Finally, some of the major impediments to the realization of this strategy will be discussed.

• Journal of the Korea Society of Computer and Information
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• v.16 no.5
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• pp.93-100
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• 2011

In this paper, we propose a FDR(False Data Reduction) strategy for P2P environment that reduces false data. The key idea of our strategy is that we use FDR algorithm to stop transmitting of false data and to delete that. If a user recognizes false data in downloaded-data and the user's peer requests the others to stop the transmission of the false data immediately. Also, the FDR algorithm notifies the other peers to prohibit spreading of the false data in the environment. All this procedure is possible to be executed in each peer without any lookup server. The FDR algorithm needs only a little data exchange among peers. Through simulation, we show that it is more effective to reduce the network traffic than the previous P2P strategy. We also show that the proposed strategy improves the performance of network compared to previous P2P strategy. As a result, The FDR strategy is decreased 9.78 ~ 16.84% of mean true data transmission time.

• Structural Engineering and Mechanics
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• v.51 no.6
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• pp.909-922
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• 2014

In this paper, we present an alternative seismic design strategy for cable stayed bridges with concrete pylons when subjected to strong ground motions. The comparison of conventional seismic design using supplemental dampers (strategy A) and the new strategy using nonlinear seismic design of pylon columns (strategy B) is exemplified by one typical medium span cable stayed bridge subjected to strong ground motions from 1999 Taiwan Chi-Chi earthquake and 2008 China Wenchuan earthquake. We first conducted the optimization of damper parameters according to strategy A in response to the distinct features that strong ground motions contain. And then we adopted strategy B to carry out seismic analysis by introducing the elastic-plastic elements that allowing plasticity development in the pylon columns. The numerical results show that via strategy A, the earthquake induced structural responses can be kept in the desired range provided with the proper damping parameters, however, the extra cost of unusual dampers will be inevitable. For strategy B, the pylon columns may not remain elastic and certain plasticity developed, but the seismic responses of the foundation will be greatly decreased, meanwhile, the displacement at the top of pylon seems to be not affected much by the yielding of pylon columns, which indicates the pylon nonlinear design can be an alternative design strategy when strong ground motions have to be considered for the bridge.

• Korean Management Science Review
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• v.23 no.1
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• pp.75-85
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• 2006

The rectilinear Steiner tree problem (RSTP) is to find a minimum-length rectilinear interconnection of a set of terminals in the plane. It is well known that the solution to this problem will be the minimal spanning tree(MST) on some set Steiner points. The RSTP is known to be NP-complete. The RSTP has received a lot of attention in the literature and heuristic and optimal algorithms have been proposed. A key performance measure of the algorithm for the RSTP is the reduction rate that is achieved by the difference between the objective value of the RSTP and that of the MST without Steiner points. A hybrid evolutionary strategy on RSTP based upon nodes set is presented. The computational results show that the hybrid evolutionary strategy is better than the previously proposed other heuristic. The average reduction rate of solutions from the evolutionary strategy is about 11.14%, which is almost similar to that of optimal solutions.

• Asia pacific journal of information systems
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• v.12 no.4
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• pp.173-192
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• 2002

Internet-based on-line firms have focused on the development of new business models with an assumption that this new model would create their competitiveness. At the same time, off-line firms have opened new marketing channels on the internet in order to defend their position against on-line firms. Based on Porter's well-known generic strategy, this study compares between on-line firms and on-offline firms i) whether these two types of firms take different strategies among cost reduction, marketing differentiation, innovation differentiation, and focus and ii) how the performance of these two types of firms is affected by different strategy types. The result shows that on-offline firms prefer the strategy of marketing differentiation and innovative differentiation while the strategy of cost reduction and focus are taken without significant difference between online firms and on-offline firms. Also it is found that even though the strategy of marketing differentiation and innovation differentiation are more preferred by on-offline firms than on-line firms, these two strategy types have a significant influence on the on-line firms' performance while the focus strategy has a significant influence on the on-offline firms' performance. Other managerial implications are discussed.

• International Journal of Aeronautical and Space Sciences
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• v.2 no.2
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• pp.19-27
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• 2001

This research attempts to find an active control strategy which reduces acoustic power and acoustic energy in lightly-damped enclosed sound field such as a vehicle compartment or an operating room of heavy industrial machinery. An active control strategy, which takes into consideration of the acoustic radiation power of the source as a cost function, is formulated and examined to find capability of reducing noise. An adaptive filtering algorithm for sound power control is suggested and implemented to control lightly-damped sound field. To verify the method, sound power based active noise control algorithm was implemented on a rectangular box with lightly-damped wall, and popular acoustic energy based control with modal coupling reduction was performed to compare the noise reduction performance. It was shown that a total sound power based strategy provides a practical mean for global noise reduction for lightly damped sound field.

• Journal of Information Technology Services
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• v.16 no.3
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• pp.1-15
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• 2017

This study is aimed to find out which factors among firm-specific resources, industry-based competition, and institutional conditions affect strategies for Korean IT manufacturing companies when they expand their business overseas, especially to Vietnam in this study. Also, it attempts to reveal which strategies among cost reduction, mass production, and localization affect performance of overseas expansion. Based on Strategy Tripod Theory as an integrating point-of-view embracing resource-based view, industry-based view, and institution-based view, research model was developed and tested through the survey of 83 Korean IT manufacturing companies expanded their business to Vietnam. Research findings show that (1) communication competency, industry competitiveness, industry attractiveness, and regulation of partner country affect cost reduction strategy. (2) International experience, communication competency, international orientation, and competitiveness is significantly associated with mass production strategy. (3) And international experience, communication competency, and industry competitiveness affect localization. (4) Ultimately, mass production strategy and localization strategy significantly increase performance of expansion to Vietnam. The theoretical contribution of this study is to adopt an integrative approach based on strategy tripod theory. As practical implications, it suggests factors and strategies that IT manufacturing companies interested in expansion to Vietnam should consider. In sum, we believe this study can contribute to Korean IT manufacturing industry by suggesting key success factors and appropriate strategies for overseas expansion.

• Journal of Power Electronics
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• v.14 no.3
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• pp.519-530
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• 2014

A novel simplified pulse width modulation(PWM) strategy for neutral point clamped (NPC) three-level converter is proposed in this paper.The direct output voltage modulation is applied to reduce the calculation time. Based on this strategy, several optimized control methods are proposed. The neutral point potential balancing algorithm is discussed and a fine neutral point potential balancing scheme is introduced. Moreover, the minimum pulse width compensation and switching losses reduction can be easily achieved using this modulation strategy. This strategy also gains good results even with the unequal DC link capacitor. The modulation principle is studied in detail and the validity of this simplified PWM strategy is experimentally verified in this paper. The experiment results indicated that the proposed PWM strategy has excellent performance, and the neutral point potential can be balanced well with unequal DC link captaincies.