• Journal of electromagnetic engineering and science
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• v.16 no.4
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• pp.199-205
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• 2016

We present a novel schematic using a 3-dB coupler to transmit radiofrequency (RF) power to two receivers selectively. Whereas previous multiple receiver supporting schemes used hardware-switched methods, our scheme uses a soft power-allocating method, which has the advantage of variable power allocation in real time to each receiver. Using our scheme, we can split the charging area and focus the RF power on the targeted areas. We present our soft power-allocating method in three main points. First, we propose a new power distribution hardware structure using a FPGA (field-programmable gate array) and a 3-dB coupler. It can reconfigure the transmitting power to two receivers selectively using accurate FPGA-controlled signals with the aid of software. Second, we propose a power control method in our platform. We can variably control the total power of transmitter using the DC bias of the drain input of the amplifier. Third, we provide the possibility of expansion in multiple systems by extending these two wireless power transfer systems. We believe that this method is a new approach to controlling power amplifier output softly to support multiple receivers.

• Journal of computational fluids engineering
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• v.17 no.2
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• pp.35-41
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• 2012

This paper presents incompressible Navier-Stokes solution algorithm for 2D Free-surface flow problems on the Cartesian mesh, which was implemented to run on Graphics Processing Units(GPU). The INS solver utilizes the variable arrangement on the Cartesian mesh, Finite Volume discretization along Constrained Interpolation Profile-Conservative Semi-Lagrangian(CIP-CSL). Solution procedure of incompressible Navier-Stokes equations for free-surface flow takes considerable amount of computation time and memory space even in modern multi-core computing architecture based on Central Processing Units(CPUs). By the recent development of computer architecture technology, Graphics Processing Unit(GPU)'s scientific computing performance outperforms that of CPU's. This paper focus on the utilization of GPU's high performance computing capability, and presents an efficient solution algorithm for free surface flow simulation. The performance of the GPU implementations with double precision accuracy is compared to that of the CPU code using an representative free-surface flow problem, namely. dam-break problem.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.10
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• pp.749-757
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• 2002

Excessive vibration in flexible structures is a problem encountered in many different fields, causing fatigue of structural components. Passive techniques, though sometimes limited in their capabilities, have been used in the past to attenuate vibrations. Recently active techniques have been developed to enhance vibration control performance beyond that provided by their passive counterparts. Most often, the focus of active control methods has been to suppress structure displacements. In cases where vibration results in structure failures, displacement suppression may not be the best choice of control approaches (it can, in fact, increase dynamic loads which would be even more harmful to supports) . This paper presents two optimal control methods for attenuating steady state vibrations in flexible structures. One method minimizes shaft displacements while another minimizes dynamic reaction forces. The two methods are applied to a model of a typical flexible structure system and their results are compared. It is found that displacement minimization can increase loads, while load minimization decreases loads.

• Journal of Korea Society of Industrial Information Systems
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• v.19 no.3
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• pp.75-85
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• 2014

This paper is to develop and estimate a closed form inflation model using the estimates for real marginal costs in manufacturing industries during the sample period 1975-2010. The production function in manufacturing industry incorporates labor, capital, domestic material, and foreign material, assuming constant returns to scale technology and AR(1) process of technological coefficient. We derive real marginal costs from firm's cost minimization with quarterly data and provide new evidences on the new Keynesian Phillips curve for Korea. The main empirical result is that the closed form coefficients ${\delta}_1$ and ${\delta}^{-1}_2$ in manufacturing for PPI inflation proved to be 0.5086 and 0.8779 respectively, similar to the estimates in the U.S. case. These results also are consistent with the functional relationship between the coefficients in hybrid model and its closed form. Thus the paper suggests that the empirical studies on inflation dynamics need to focus on the manufacturing industry with market power, treating PPI inflation as the dependent variable.

• Archives of design research
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• v.19 no.3 s.65
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• pp.31-44
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• 2006

With 'the improvement of brand image through the consolidation of the online and offline brand images' as the goal, the focus of this study lies in brand color. In order to analyze the differences between the website and offline image of a brand, as felt by the consumers, a survey on color image was conducted. Using the results of the survey as the foundation, a comparative analysis of online and offline color images was conducted, and the discrepancies between the two specified. Furthermore, solutions in creating websites that cultivate brand consolidation through color consolidation are presented. Using the thesis 'Research on the Color Strategy of Brand-name Coffees,' as a guide, and supplementing it with necessary improvements, this study presents three areas to consider when designing or managing websites for offline brands. First of all, color image is not static but variable, meaning that it appeals to the consumers differently, depending on change in other brands, trends, consumer point of view, etc. Thus, color image must be flexible. Secondly, overall brand image can be improved by its offline color. However, it should be realized that identical colors could produce different results online and off. Lastly, in general, the online image falls behind the offline image, in regard to color strategy. Therefore, more meticulous and carefully planned color design is necessary, as is the consideration of the unique and distinctive qualities of the World Wide Web.

• Journal of Fashion Business
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• v.11 no.1
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• pp.86-96
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• 2007

The purpose of this study was to examine which variables affect customer relationship management in discount store focusing on satisfaction, trust and commitment. A total of 360 participants who had purchased fashion products in discount store were used in this study. The data was analyzed by factor analysis, correlation analysis and regression analysis using SPSS program. As the result, benefits, information, reputation, product, location, salesperson and price factor were extracted. The price, information, reputation, product and location variables had the effects on satisfaction, especially, price had the major effects on satisfaction. The satisfaction, information, salesperson, price and location had the effects on trust. The satisfaction, trust, information, benefits and product had the effects on commitment. The reputation variable had direct effect on relationship maintenance. Also, satisfaction, trust and commitment had the effects on relationship maintenance. Specifically commitment had higher effect on relationship maintenance than satisfaction and trust did. The results of this study would provide CRM marketing strategy for fashion marketers of discount store.

• Journal of the Korean Operations Research and Management Science Society
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• v.28 no.4
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• pp.85-104
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• 2003

Customer retention is more emphasized for internet business than off-line shopping-malls. The loyals not only purchase a lot but also recommend the mall to new customers quickly using internet media, and there have been many studies on this subject. In this study, customer satisfaction and trust are suggested as preceding variables that have an influence on customer loyalty, and switching gains are suggested as a moderating variable between customer satisfaction & trust and customer loyalty. Many people think it would be easier to change business connection and customer loyalty for internet shopping-malls would be very low. This study, however, concluded that customer satisfaction and trust had a significant influence on customer loyalty even in internet shopping-mall, and that switching gains had moderating effect between satisfaction-attitudinal loyalty and trust-behavioral loyalty. These results are meaningful in that customer satisfaction or trust should be emphasized even on internet business and that switching gains can be strategic focus in building up customer loyalty and retention.

• Journal of Korean Library and Information Science Society
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• v.30 no.2
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• pp.93-121
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• 1999

The purpose of this study is to develop an experimental model for information needs assessment, which could be utilized to investigate the 'real' information needs of the user(or group). The focus was on the perspectives of users rather than those of system managers. In details, this study identifies the conceptual definition of the keyword 'information need', analyzes the limitation and problems the previously conducted needs assessments in this area, and finally, develops an experimental model based on the cognitive and affective variables which might influence both production and strength of information needs in the user(or group}. The model emphasizes four influencing variable, namely, individual, work-related, organizational(or institutional), and socio-cultural variables. Also discussed is the relationships among these variables.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.1
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• pp.291-299
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• 2020

The purpose of this study focuses on finding the influences of social capital on personal happiness by studying service industry employees. This current study utilized a questionnaire survey method which was used to collect the analysis data, from July 20 to August 10 in 2019. 281 questionnaires were gathered in Korea and the statistical analysis was conducted. This study recognized social capital as 3 independent variables and personal happiness as a dependent variable. Social capital is composed of the social network, social trust and social norms. First, the social network consisted of the satisfaction degree in one's social relations and the social interaction degree. Second, social trust is composed of the trust degree with ones neighbors in the same local area. Last, social norms are consisted of reciprocity, participation and a sense of belonging one feels in the same society. The findings of this study were as follows: first, it was found that social network, social trust, and social norms made affirmative influences on personal happiness of the employees. Second, the social network and social norms made statistically significant influences with personal happiness, but social trust was shown to not have similar influence.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.1
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• pp.131-140
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• 2020

The purpose of this study is to derive various clues for the establishment of marketing strategies for companies that produce and sell high-involvement products for Millennials who are not the subject of current consumption but who will lead future consumption. For this purpose, this study aimed to derive 17 factors of high-involvement product selection attributes through FGI, and its relationship on repurchase intention after make a variable through PCA. A total of 158 valid questionnaires were used, and IPA, independent sample t-test, regression analysis, and hierarchical controlled regression analysis were performed. The results showed that overall, external and internal selection factors had a positive influence on repurchase intentions, and in particular, appealing to internal and external selection factors in order to promote repurchase intention. Meanwhile, the Millennials were found to have no gender difference. Therefore, the company producing and selling high-involvement products suggests that it is necessary to make a priority effort to secure brand awareness, trust in product producers, store trust, and product self-reputation as components of internal selection factors. It was also concluded that more strategic efforts were needed to focus on and appeal to the characteristics of the Millennial itself rather than to consider gender differences.