• Journal of Power Electronics
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• 제10권6호
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• pp.635-642
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• 2010

The paper presents a multimedia educational program of DC servo drives for distant learning with a special emphasis on sliding mode control. The program contains of three parts: animation, simulation and internet based measurement. The animation program explains the operation of DC motors, gives its time- and frequency-domain equations, transfer functions and the theoretical background necessary for controller design for DC servo motors. The simulation model of the DC servo motor and the controller can be designed by the students based on the animation program. The students can also test their controllers through the internet based measurement, which is the most important part from engineering point of view. After the measurements are executed, the students can download the measured data and compare them to the simulation results.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권5호
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• pp.1356-1376
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• 2023

Software effort estimation is one of the most difficult tasks in software development whereas predictability is also of equal importance for strategic management. Accurate prediction of the actual cost that will be incurred in software development can be very beneficial for the strategic management. This study discusses the latest trends in software estimation focusing on analogy-based techniques to show how they have improved the accuracy for software effort estimation. It applies the standard deviation technique to the expected value of analogy-based estimates to improve accuracy. In more than 60 percent cases the applied technique of this study helped in improving the accuracy of software estimation by reducing the Magnitude of Relative Error (MRE). The technique is simple and it calculates the expected value of cost or time and then uses different confidence levels which help in making more accurate commitments to the customers.

• 대한가정학회지
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• 제42권11호
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• pp.223-235
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• 2004

This study investigated the integrated effects of family and school factors on the cyber behavior of adolescents. Specifically, the purposes of this study were to categorize adolescents into groups by family and school factors and to find investigate differences among the groups regarding cyber behavior (internet use, internet purpose, and internet experience). no study distributed the questionnaires to middle and high school adolescent students of five representative cities in South Korea. The total respondents were 2240 (960 from Seoul/kyongki, and 320 each from Taegu, Pusan, Kwangiu, and Taejon). The response rate w3s 98.7%. no data were analyzed by factor analysis, cluster analysis, ANOVA, and Duncan test. The results showed that Korean adolescents were segmented into four groups (family preference/school preference group, family dissatisfaction/teacher dissatisfaction group, family average/school average group, family average/peer dissatisfaction group). The four groups were significantly different in regard to cyber behavior. For example, the family dissatisfaction/teacher dissatisfaction group u%d internet to relieve stress and used communication more than the other groups. Also, the group had more diverse cyber behavior including internet addiction. The implications of the study were further discussed.

• 대한가정학회지
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• 제40권6호
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• pp.69-83
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• 2002

This study examined the effects of demographic variables on buying behavior, and investigated buyers'perceived value and risk perception of the internet shopping mall. The sample was collected by a department store in Daegu, and it included 1,732 individuals using the Cyber Mall. Research methods used in this study were simple statistics, t-test and ANOVA. The buyers perceived values through the internet shopping mall were classified into five categories-price, time, convenience, intrinsic attributes, reliability and the risk perception also was classified such as the overall purchasing process, quality of products, exposure of the personal information, delivery system, refund and exchange. The major findings of this study were 1) most important categories affecting their buying behavior were the value of convenience and following values in order were time, price, reliability, intrinsic attributes. 2) the risk perception were overall purchasing behavior, quality of products, exposure of personal information, delivery, and refund & exchange in order. 3) age of buyers, buying experience on the internet shopping mall, and gender were the important factors affecting the buyers'perceived value and risk. 4) the study also, showed that according to the variety of products, buyers perceived the value and risk differently, for example, the price was the most important perceived value in case of food product. The implication of the study is to strategically suggest how to enhance the buyers'perceived value and diminish perceived risk of different products.

• 대한가정학회지
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• 제42권7호
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• pp.103-118
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• 2004

The purpose of this study was to investigate the discriminative factors of on-line consumer satisfaction. Data were obtained from an online questionnaire survey with 1089 online shoppers who had the experience of either purchasing or visiting a fashion on-line shopping mall from the panel of an online survey agency(www.inr.co.kr) and 1049 responses were analyzed. For analysis of data, descriptive analysis, Cronbach's ${\alpha}$, $\chi$$^2$-test, one-wav ANOVA, Ducan test and stepwise regression analysis were applied. The results of this study were as follows: Firstly as a result of differences of purchasing experience and future purchasing intention via internet, 4 consumer groups were generated: internet patronizing group, trial and unsatisfied experience group, future purchasing intention group, and internet carelessness group. Secondly each group differences was found in demographic variables such as age, marital status, income and employment status. Croup differences were also found in personal, product, and store variables except tangibility. According to consumer groups, different factors were directly impact on consumer satisfaction.

• 대한가정학회지
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• 제48권1호
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• pp.67-81
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• 2010

Consumer researchers found that compulsive buying was a part of a category of compulsive consumption that was interrelated to addictive and repetitive behaviors. The present study empirically examined the co-morbidity of compulsive buying and Internet addiction among e-commerce users in terms of consumption disorders. Although the prevalence of Internet use and on-line sales remarkably increase in recent years, almost no study examines on-line compulsive buying behavior. This study explored the link between compulsive buying and Internet addiction among e-commerce users, and investigated the characteristics of on-line shoppers with respect to two forms of compulsive consumption, which were divided into compulsive buying and Internet addiction. Additionally, factors that related to compulsive buying behaviors among e-commerce users were also examined. The present research was conducted using a convenience sample of 394 young adults between the ages of 20-30, and the Faber and O'Guinn's DSCB scale and the Widyanto's Internet addiction scale (IA) were used. Confirmatory factor analyses were utilized to evaluate the structure of the DSCB and IA, and a Probit model was used to examine determinants for the compulsive buying behaviors of e-commerce users. E-commerce users were classified into four groups; high compulsion and high addiction, low compulsion and low addiction, high compulsion and low addiction, and low compulsion and high addiction. Consumers with high compulsion and high addiction spent higher amounts of money on their on-line purchases and were frequently connected with the Internet compared to the three other consumer groups. Consumers with compulsive buying behaviors were also found to have significantly greater Internet addiction tendencies than typical buyers. Compulsive buyers were more likely to engage in Internet addiction and the number of purchasing via on-line shopping mall, and had higher materialism. Policy implications and suggestions for consumer education programs were discussed.

• Asia pacific journal of information systems
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• 제17권4호
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• pp.113-132
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• 2007

Price rigidity involves prices that do not change with the regularity predicted by standard economic theory. It is of long-standing interest for firms, industries and the economy as a whole. However, due to the difficulty of measuring price rigidity and price adjustments directly, only a few studies have attempted to provide empirical evidence for explanatory theories from Economics and Marketing. This paper proposes and validates a research model to examine different theories of price rigidity and to predict what variables can explain the observed empirical regularities and variations in price adjustment patterns of Internet-based retailers. I specify and test a model using more than 3 million daily observations on 385 books, 118 DVDs and 154 CDs, sold by 22 Internet-based retailers that were collected over a 676-day period from March 2003 to February 2005. I obtained a number of interesting findings from the estimation of our logit model. First, quality seems to play a role-I find that both price levels as proxies for store quality, and information on the quality of a product consumers have, affect online price rigidity. Second, greater competition(i.e., less industry concentration) leads to less price rigidity(i.e., more price changes) on the Internet. I also find that Internet-based sellers more frequently change the prices of popular products, and the sellers with broader product coverage change prices less frequently, which seem due to economic forces faced by these Internet-based sellers. To the best of my knowledge, this research is the first to empirically assess price rigidity patterns for multiple industries in Internet-based retailing, and attempt to explain the variation in these patterns. I found that price changes are more likely to be driven by quality, competitive and economic considerations. These results speak to both the IS and economics literatures. To the IS literature these results suggest we take economic considerations into account in more sophisticated ways. The existence and variation in price rigidity argue that simplistic assumptions about frictionless and completely flexible digital prices do not capture the richness of pricing behavior on the Internet. The quality, competitive and economic forces identified in this model suggest promising directions for future theoretical and empirical work on their role in these technologically changing markets. To the economics literature these results offer new evidence on the sources of price rigidity, which can then be incorporated into the development of models of pricing at the firm, industry and even macro-economic level of analysis. It also suggests that there is much to be learned through interdisciplinary research between the IS, economics and related business disciplines.

• 대한가정학회지
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• 제40권12호
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• pp.49-61
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• 2002

The purpose of this study was to investigate the effect of clothing involvement on the perceived risk in internet shopping and store selection criteria. The subjects used for the study were 210 male and 338 female college students. The clothing involvement consisted of pleasure, symbolism, and selection difficulty factors. The perceived risk consisted of size/defect risk, social psychological risk, privacy risk, delivery risk, and price risk. The store selection criteria had security/service, entertainment/variety, price/convenience factors. The results showed that consumers were segmented by four groups based on clothing involvement factors: clothing pleasure group, symbolism group, confidence group, and low clothing involvement group. The four segmented groups differed in regard to the perceived risk, store selection criteria, and demographics. For example, clothing pleasure group perceived the size/defect risk and social psychological risk higher than did the other groups. Also, the clothing pleasure group considered entertainment/variety more important and had younger female consumers.

• 대한가정학회지
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• 제38권2호
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• pp.139-153
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• 2000

The purpose of this study is to prove asymmetric Consumer Information on Electronic Commerce. For this purpose, 93 internet shopping-malls was analyzed into three contents of consumer information. Major findings are as follows : First, the overall level of consumer information contents through purchase process was very low. The reason is that most electronic consumers were dissatisfied with consumer information provided by internet shoppingmall. Second, consumer information of purchase-stage was insufficient for electronic consumer. Especially most shoppingmalls did not provide Use-information and comparing information. This implies electronic consumer can't meet their consumer information needs, so they cannot make rational decision. Third, consumers were faced with asymmetric Consumer Information problem on electronic commerce. So consumer education for electronic commerce is needed.

• 대한가정학회지
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• 제39권6호
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• pp.51-60
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• 2001

The purpose of this study is analyze buying time use and it's influential factors of buying types. The major findings are follows: (1) Physiological time, household work time, earning time & leisure time are respectively similar to The Investigation of Korean Life Time(1991,1995). (2) Buying time of wives who perceived time deficit are shorter than those who did not perceive so. (3) Internet shopping time is 18minutes, direct visiting shopping time is 68minutes and those who directly visit shops pursued leisure effect. (4) Influential factors of internet shopping time are educational level, household work time, earning time & leisure time and direct visiting shopping time are husband's job, household work time, earning tile & leisure time.