• KIEE International Transactions on Power Engineering
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• 제5A권2호
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• pp.109-115
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• 2005

Recently, the needs and concerns regarding power loss have been increasing according to energy conservation at the level of the national policies and the business strategies of power utilities. In particular, the issue of power loss is the main factor for determining rates for electrical consumption in the deregulation of the electrical industry. However, because of the lack of management for power loss load factors (LLF) it is difficult to make a calculation for power loss and to make a decision concerning the electric rates. Furthermore, loss factor (k-factor) in Korea, which is of primary significance in the calculation of distribution power loss, has been used as a fixed value of 0.32 since the fiscal year 1973. Therefore, this study presents the statistical calculation methods of the loss factors classified by load types and seasons by using the practical data of 65 primary feeders that have been selected by appropriate procedures. Based on the above, the algorithms and methods, as well as the optimal method of the distribution loss management classified by facilities such as primary feeders, distribution transformers and secondary feeders is presented. The simulation results demonstrate the effectiveness and usefulness of the proposed methods.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.2090-2092
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• 2004

In this paper, the new measurement methodology of characteristics of the vibratory micro gyroscope using Quality factor and the resonant displacement was proposed. Because the Quality factor has a large error under the high Quality factor condition, it is difficult to analyze the characteristics of the vacuum packaged vibratory micro gyroscopes with the Quality factor. We analyzed mechanical characteristics of gyroscope with the value of Quality factor. We described measurement errors of mechanical characteristics of micro gyroscopes. The measured value of Quality factor is 47532 and error range of Quality factor is from -29.8 % to 73.9 %. The value of resonant displacement is 3.4${\mu}m$ and the measurement error is 2.9 %. From the result of Quality factor degradation and resonant displacement degradation, 1698 days and 1503 days were estimated as Time To Failure (TTF), respectively. The range of estimation error of Quality factor degradation and resonant displacement degradation is calculated from 1246 days to 1832 days and from 1456 days to 1537 days, respectively. We can analyze the characteristics of the vibratory gyroscope using the quality factor when the Quality factor is smaller than 10,000. Also we can analyze that using the resonant displacement when the Quality factor is larger than 10,000.

• Asia Marketing Journal
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• 제15권2호
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• pp.29-47
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• 2013

Distribution channel decisions involve long-term commitments with other firms that are very difficult to change or replace. In particular, marketing channel decisions in emerging markets are much more complicated due to unfamiliar conditions and problems such as lack of market data and distribution systems. Therefore, when a company considers changing or introducing a marketing channel in an area, it is much more difficult to judge its effectiveness in an emerging market than in a developed market. In this study, we investigate the development process of a new direct marketing channel of Hongfu Fertilizer Company (hereafter Hongfu), a medium-sized Chinese fertilizer manufacturer, and propose an approach to test the feasibility of this new marketing channel in the Chinese rural market. We measure the effectiveness of Hongfu's new marketing channel from two perspectives: i) from customers' perspective through direct responses of farmers, which showed that a new channel can increase the convenience and lower the purchasing costs for the farmers, and ii) from the company's perspective, by calculating the incremental profit of the company using the expansion factor (T/Q) method, which suggested that the execution of Hongfu's strategy to expand a new marketing channel will result in an increase in profits. The results of this study contribute to the development of a methodology to test the feasibility of a new direct marketing channel in the emerging markets such as the Chinese rural market. Traditional and indirect distribution channels in emerging markets are generally not very efficient and difficult to change. Especially, in emerging markets, like the Chinese rural market, the methods of testing channel feasibility must be different from that of developed markets. Considering market situations, market experiments can be more effective then systematic market surveys in testing channel feasibility in emerging markets. This study implies that managers must learn to cope with a transition from the traditional marketing channels in emerging markets. With the development in farmers' understanding of marketing concept, the transition from traditional marketing channel is unavoidable for all firms. Farmers in China are generally very conservative, however, their buying behaviors are changing. Therefore, fertilizer companies should try to adjust in accordance with farmers' demand characteristics that the efforts to meet the economic needs of farmers with new marketing channels as well as trust building are critical in the near future.

• BMB Reports
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• 제42권12호
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• pp.823-828
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• 2009

Techniques for analyzing protein-DNA interactions on a genome-wide scale have recently established regulatory roles for distal enhancers. However, the large sizes of higher eukaryotic genomes have made identification of these elements difficult. Information regarding sequence conservation, exon annotation and repetitive regions can be used to reduce the size of the search region. However, previously developed resources are inadequate for consolidating such information. CONVIRT is a web resource for the identification of transcription factor binding sites and also features comparative genomics. Genomic information on ortholog-independent conserved regions, exons, repeats and sequences is integrated into the virtual chromosome, and statistically over-represented single or combinations of transcription factor binding sites are sought. CONVIRT provides regulatory network analysis for several organisms with long promoter regions and permits inter-species genome alignments. CONVIRT is freely available at http://biosoft.kaist.ac.kr/convirt.

• 한국세라믹학회지
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• 제42권1호
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• pp.1-6
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• 2005

In aqueous alumina tape casting, the effects of altering the composition of the suspensions, the binders and the casting thickness were studied. The rheological behavior of the suspensions and the defects of the dried tapes were examined and the relationships between them are discussed. The changes in the defect regions reported in the previous paper were related with the rheological properties with variations of the binder, the composition and the casting thickness. The shear thinning factor increased with the organic content and the solid content (the decrease of water content). The apparent viscosity increased with the shear thinning factor. The relation between the shear thinning factor and the log apparent viscosity was similar for all binder types. In the relation between the defect free region and the rheological properties, the defect free region became narrower with increasing casting thickness. The defect free region is independent of binder type. Therefore, the thicker tape is more difficult to produce in aqueous alumina tape casting. Knowledge of the rheological properties of the suspensions could help Predict the defect type and the possibility of defect free dried tapes.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.163-167
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• 2000

This paper presents the digital control of single-phase power factor correction(PFC) converter which has the variable gain according to the condition of inner control loop error. Generally the gain of inner current control loop in single-stage PFC converter has a constant magnitude. This has a bad influence on the power factor because current loop doesn't operate smoothly in the condition that input voltage is low In particular a digital controller has more time delay than an analog controller and degrades This drops the phase margin of the total digital PFC system,. It causes the problem that the gain of current control loop isn't increased enough. In addition the oscillation happens in the peak value of the input voltage open loop PFC system gain changes according to ac input voltage. These aspects make the design of the digital PFC controller difficult The digital PFC controller presented in this paper has a variable gain of current control loop according to input voltage. The 1kW converter was used to verify the efficiency of the digital PFC controller.

• 동력기계공학회지
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• 제2권3호
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• pp.21-26
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• 1998

Numerical simulations for various fluid flows require enormous computing time during iterations. In order to solve this problem, several techniques have been proposed. A SOR method is one of the effective methods for solving elliptic equations. However, it is very difficult to find the optimum relaxation factor, the value of this factor for practical problems used to be estimated on the basis of expertise. In this paper, the implication of the relaxation factor are translated into fuzzy control rules on the basis of the expertise of numerical analysers, and fuzzy controller incorporated into a numerical algorithm. From two cases of study, Poisson equation and cavity flow problem, we confirmed the possibility of computational acceleration with fuzzy logic and qualitative reasoning in numerical simulations. Numerical experiments with the fuzzy controller resulted in generating a good performance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 B
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• pp.781-783
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• 1999

A storage or transmission of image is difficult without image compression processing because the numbers of generated or reborned image data are very much. In case of the random signal, image compression efficiency is low doing without loss of image information, but compressibility by using JPEG is better. We used Huffman code of JPEG, it assigne the low bit value for data of a lot of generated frequency, assigne the high bit value for data of a small quantity. This paper improved image compression efficiency with transformming Q-factor and certified the results with compressed image. A proposed method is very efficience for continuos a color tone image.

• Journal of the Korean Data and Information Science Society
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• 제18권1호
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• pp.123-139
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• 2007

Recently, Super-Super-Market(SSM) is facing more and more difficult situation due to the expansion of hypermarket and target marketing of specialized shop. In this situation, Customer Satisfaction Management(CSM) is emerging as a core business factor to make continuous growth without competitive exclusion. Especially, the first factor in CSM in distribution industry is a Service Quality Satisfaction. In this paper, with a selection of 3-markets as a sample for the research, I have tried to look for necessary Service Quality(SQ) factors in SSM and deduced Service Quality Index(SQI), loyalty and Index of detail factor in SQ through survey. Based on these results, strategic factors required to improve SQ was found and strategic directions for SQ were proposed through matrix portfolio analysis.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.3-7
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• 1996

Metal Matrix Composite(MMC) material of 30% SiC particulate based on A1 matrix was machined by drilling and Electrical Discharge Machining (EDM) processes. When drilling process was executed, surface fracture due to brittle property near the bottom was found. It was also found the possiblity of difficult shape of EDM process for MMC material, but few the research about basic EDM characteristics. Material Removal Rate(MRR) was examined for different conditions and the surface morphology was evaluated by roughness values and Scanning Electron Microscopy(SEM) research. The higher the current is, the more MRR was obtained but the higher MRR was showed around 0.45 duty factor. The average roughness of EDMed surface was slightly changed with increased pulse current and increases with duty factor. The SEM photographs of EDMed surface showed recast region after melting.