• The Journal of the Korea Contents Association
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• v.10 no.9
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• pp.363-374
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• 2010

Supply chain (SC) strategies will influence corporate performance and customer satisfaction. However, few empirical research has investigated the impact of the gap between prescriptive and current strategy on customer satisfaction. Based on the profile analysis with data from 31 products, the results of this study show the significant relationship between customer satisfaction and the fit between SC context and speculation-postponement strategies. The results imply that different SC strategies should be applied in accordance with product attributes and supply environments.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.12
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• pp.41-50
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• 1999

In this paper, the new VLSI architecture of a reconstruction filter for morphological image segmentation is proposed. The filter, based on the $h_{max}$ operation, simplifies the interior of each region while preserving the boundary information. The proposed architecture adopts a partitioned memory structure and an efficient image scanning strategy to reduce the operations. The proposed memory partitioning scheme makes it possible that every data required for processing can be read from each memory at a time, resulting in parallel data processing. By the extended connectivity consideration, the operation is much decreased because more simplification is achieved in scanning stage. The selective raster scan strategy endows the satisfactory noise removal capability with negligible hardware complexity increase. The proposed architecture is designed using VHDL, and functional evaluation is performed by the CAD tool, Mentor. The experiment results show that the proposed architecture can simplify image profile with less than 18% operations of the conventional method.

• The Transactions of the Korean Institute of Power Electronics
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• v.24 no.6
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• pp.419-427
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• 2019

Several multilevel converter topologies have been proposed and compared. The three-level (3L) neutral-point-clamped (NPC) topology is promising and widely accepted. However, this topology suffers from uneven loss distribution among switches due to its fixed switching strategy. The 3L active NPC (ANPC) topology, which exhibits improved loss distribution profile, was proposed to address this disadvantage. The 3L T-NPC topology, a hybrid configuration of 2L and 3L NPC topologies, was introduced to address not only the loss distribution problem but also the reduction in the number of switches. In the present research, the application of these three topologies in PMSG-based medium-voltage wind turbines was investigated. The power devices considered were 10 kV IGCTs. Performance was evaluated in terms of a power loss of 10 kV IGCT for each NPC topology, which is a crucial indicator of thermal behavior, reliability, cost, and lifetime of any converter. The comparison was performed using ABB make 10 kV IGCT 5SHY17L9000 and the simulation tool PLECS.

• Journal of Astronomy and Space Sciences
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• v.32 no.4
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• pp.379-386
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• 2015

This work presents fuel-optimal altitude maintenance of Low-Earth-Orbit (LEO) spacecrafts experiencing non-negligible air drag and J2 perturbation. A pseudospectral (direct) method is first applied to roughly estimate an optimal fuel consumption strategy, which is employed as an initial guess to precisely determine itself. Based on the physical specifications of KOrea Multi-Purpose SATellite-2 (KOMPSAT-2), a Korean artificial satellite, numerical simulations show that a satellite ascends with full thrust at the early stage of the maneuver period and then descends with null thrust. While the thrust profile is presumably bang-off, it is difficult to precisely determine the switching time by using a pseudospectral method only. This is expected, since the optimal switching epoch does not coincide with one of the collocation points prescribed by the pseudospectral method, in general. As an attempt to precisely determine the switching time and the associated optimal thrust history, a shooting (indirect) method is then employed with the initial guess being obtained through the pseudospectral method. This hybrid process allows the determination of the optimal fuel consumption for LEO spacecrafts and their thrust profiles efficiently and precisely.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2000.04a
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• pp.187-196
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• 2000

A lot of Internet shopping malls strive for obtaining a competitive advantage over others in an increasingly tighter electronic marketplace. To this end, understanding customer preference toward products (or services) and administering appropriate marketing strategy is essential for their continuous survival. However, only a few marketing researchers and practicioners focused on this issue, compared with academic and industry efforts devoted to traditional market segmentation. In this paper, we suggest a methodology of conjoint segmentation for electronic shopping malls. Traditional market segmentation methodologies based on customer's profile sometimes fail to utilize abundant information given while navigating around cyber shopping malls. In this methodology, we do not impose information overload to the customer for preference elicitation, but this methodology, we do not impose information overload to the customer for preference elicitation, but capture automatically generated surfing or buying data and analyze them to get useful market segmentation information. The methodology consists of 4-stages: 1) analyzing legacy homepages, 2) data preparation, 3) estimating and interpreting the result, and 4) developing marketing mix. Our methodology was to give useful guidelines for market segmentation to companies working in the electronic marketplace.

• Korea-Australia Rheology Journal
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• v.13 no.3
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• pp.131-139
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• 2001

A coupled approach is proposed for the prediction of sheet profile in sheet casting process, which combines one-dimensional analytical method on planar elongational flow region and three-dimensional numerical method on the other region. The strategy is constructed from the observations that the flow domain of sheet casting process can be separated into two parts based old the flow kinematics. The flow field in the central region of sheet, over which the planar elongational flow dominates, is possibly replaced by one-dimensional analytical solution. Then only a partial flow domain near the edge region of sheet, where the flow kinematics cannot be described by the planar elongational flow itself, requires three-dimensional numerical simulation. Good agreement is observed between the coupled approach developed in this study and the full three-dimensional numerical simulation previously developed and reported by the authors. This coupled approach may have provided flexibility with low costs to accommodate a wide range of die sizes in sheet casting process.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.3 s.43
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• pp.257-269
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• 1992

In the area of fashion business, market segmentation strategy has been paid attention for the purpose of assigning proficiently marketing resources. The use of fashion information in purchase decision process can serve as a base for market segmentation strategies. The purpose of this study was to identify four segmented profiles which are labelled as Print-oriented, Audio-visual oriented, Store intensive, and Pal advice group. Objectives were to determine fashion interest, fashion attitude and apparel selection criteria from each segment. For this study, the questionnaire was adminisered to 261 teachers and data were analyzed by using ANOVA, Regression and Pearson's Correlations. The results were as follows. 1. Print-oriented group had a positive attitude about fashion and they tended to place value on aesthetic and other-oriented criteria in selecting apparel. 2. Audio-visual oriented group had a strongly positive attitude about fashion but they tended to be less active toward buying fashion products and place much more value on other-oriented criteria in selecting apparel. 3. Store intensive group tended to be active toward buying fashion products. They had a positive attitude about fashion and placed value on aesthetic criteria in selecting apparel. 4. Pal advice group had a less positive attitude about fashion and tended to place value on economical and practical criteria in selecting apparel. Based on the profile of the each segment, it was suggested to express lingual or non-lingual symbols and to create concepts for meeting the needs of the segment

• Journal of the Korean Solar Energy Society
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• v.33 no.2
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• pp.84-92
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• 2013

Blinds are a common type of shading device and are increasingly operated automatically to overcome the limitations of manual operation. Automated blinds need to be controlled to maximize benefits of daylight in the point of occupant comfort and energy consumption. However, the previous control methods could cause occupant's distractions by the undesirable control time interval and amount of blind movement. A few researches suggested the control concept for minimizing occupant's distractions by automatic blind control, but they did not provide optimal control algorithm to be useful in practice. In this paper, we propose an optimal control algorithm for automated blinds that can maximize not only visual comfort but also sunlight penetration into buildings based on occupants' preferences on blind movement and sunlight. The proposed control algorithm can prevent solar glare on workplane and minimize occupant's distractions to maximize occupants' visual comfort.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.4
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• pp.450-455
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• 2008

A Single Nucleotide Polymorphism (SNP) is a small genetic change or variation that can occur within a DNA sequence. It's the difference of one base at specific base pair position. SNP variation occurs when a single nucleotide, such as an A, replaces one of the other three nucleotide letters-C, G, or T. On average, SNP occur in the human population more than 1 percent of the time. They occur once in every 300 nucleotides on average, which means there are roughly 10 million SNPs in the human genome. Because SNPs occur frequently throughout the genome and tend to be relatively stable genetically, they serve as excellent biological markers. They can help scientists locate genes that are associated with disease such as heart disease, cancer, diabetes. They can also be used to track the inheritance of disease genes within families. SNPs may also be associated with absorbance and clearance of therapeutic agents. In the future, the most appropriate drug for an individual could be determined in advance of treatment by analyzing a patient's SNP profile. This pharmacogenetic strategy heralds an era in which the choice of drugs for a particular patient will be based on evidence rather than trial and error (so called "personalized medicine").

• Journal of Electrical Engineering and Technology
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• v.5 no.1
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• pp.70-78
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• 2010

Elitist nondominated sorting genetic algorithm (NSGA-II) is adopted and improved for multiobjective optimal reactive power flow (ORPF) problem. Multiobjective ORPF, formulated as a multiobjective mixed integer nonlinear optimization problem, minimizes real power loss and improves voltage profile of power grid by determining reactive power control variables. NSGA-II-based ORPF is tested on standard IEEE 30-bus test system and compared with four other state-of-the-art multiobjective evolutionary algorithms (MOEAs). Pareto front and outer solutions achieved by the five MOEAs are analyzed and compared. NSGA-II obtains the best control strategy for ORPF, but it suffers from the lower convergence speed at the early stage of the optimization. Several problem-specific local search strategies (LSSs) are incorporated into NSGA-II to promote algorithm's exploiting capability and then to speed up its convergence. This enhanced version of NSGA-II (ENSGA) is examined on IEEE 30 system. Experimental results show that the use of LSSs clearly improved the performance of NSGA-II. ENSGA shows the best search efficiency and is proved to be one of the efficient potential candidates in solving reactive power optimization in the real-time operation systems.