• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6446-6451
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• 2014

Pneumatic motors are quite attractive for many applications because of their competitive price, light-weight, easy assembly, safety in hazardous areas as well as other features, such as a good force/weight ratio and operation in exceptionally harsh environments. In contrast to these advantages, pneumatic motors have limited use in applications, particularly those requiring a fast and precise response. These undesirable characteristics are due to the high compressibility of air and from the nonlinearities in pneumatic systems. This paper presents the sliding mode controller based on 3-loop(SMCB3L), which increases the load stiffness to control the rotation angle of a pneumatic motor. The characteristics for the step responses and load disturbances of the proposed controller were compared with the conventional PID controller. The experimental results showed that a properly designed SMCB3L is capable of high positioning accuracy within ${\pm}0.05mm$. Furthermore, the load stiffness of the SMCB3L can be improved 3.5 fold compared to that of PID controllers.

• The Korean Journal of Applied Statistics
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• v.23 no.3
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• pp.457-469
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• 2010

The government real estate policy has repeatedly relaxed and reinforced controls under the mutually contradictory targets. Switching over the supporting policy after the IMF crisis to the regulating policy from 2003, the government housing policy began to generate ill effects due to various regulations. This stud carefully investigates and statistically tests the transmissions of variations in the housing prices between the metropolitan areas in the early stage of the preceding administration, under the effect of the supporting scheme, and those in the late stage, under the effect of the restricting scheme. The distinctive feature between the two periods is found to be much simplified interrelationships of the price variations in the latter period. Consolidated leading role of capital sphere, by concentrated economic strength, suggest the obvious imbalance between variations in the metropolis housing prices.

• Journal of the East Asian Society of Dietary Life
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• v.12 no.4
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• pp.280-288
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• 2002

The purpose of this study is finding a solution to increase the consumption of Korean cookies by investigating and analyzing the actual consumption patterns, suggestions fur improvement and preferences for Korean cookies. The data fer this study was collected from 358 housewives living in Daegu province. Results show that 77.4% of housewives in this locale eat Korean cookies on a special day such as memorial service day of ancestors, festive day or party. The frequency of having Korean cookies were significantly different due to the income (p<.05): the higher the income, the more often people had Korean cookies. They usually purchase Korean cookies on the market rather than making them by themselves. The percentile of housewives who have never made Korean cookies before was up to 51.7% Only the housewives over fifty had some experience making the Korean cookies. The number of people who teamed the method fur making Korean cookies from their family elders increased according to their age. The reasons why they buy Korean cookies on the market are as follows: the most frequent answer (45.5%) was the price. 34.5% of the responder리s did not know how to make them. 32.1% replied that the process is too complex and troublesome. The most frequent requests for the market was expanding the diversity and improving the quality. In response to why they want the Korean cookies to be inherited. 68.8% of respondents answered that it is traditional culture. 4.01% of respondents replied that `ssalyeatgangung' is their favorite Korean cookie. 3.90% of them like 'sanja' the best and 3.91% of the housewives preferred yakwa to other Korean cookies. This study shows that the most preferred Korean cookies are yeatganjung, yakwa and sanja

• Journal of the Korea Society of Computer and Information
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• v.9 no.2
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• pp.69-79
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• 2004

For the successful IT operation outsourcing there need appropriate metrics on which both of the service clients and provider agree. The metrics are used to set up the service level objectives, which are manifested in the service level agreement with price. A study of metrics is necessary for the following reasons: First, most of the metrics used today were introduced in the early years of computers and are not satisfactory to both of the service providers and clients. Second, metrics represent the performance of system components but not end-user satisfaction. Third, because the service provider leads the outsourcing agreement, the objectives are specified more favorable to the provider. The objectives should be based on metrics that both sides fully understand and agree on.

• Journal of the Korea Fashion and Costume Design Association
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• v.20 no.3
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• pp.33-48
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• 2018

The purposes of this study were to investigate the social instrumentality of appearance, appearance orientation, and cosmetics purchasing behaviors of Chinese male consumers, and to find differences in the cosmetics purchasing behaviors of the male consumer groups, which were segmented by the social instrumentality of appearance and appearance orientation. The subjects were 400 adult males in their 20s to 30s from Gillim province in China. The measurements consisted of the social instrumentality of appearance, appearance orientation, cosmetics purchasing behavior, and the subject' demographic attributes. The data was analyzed by descriptive statistics, frequency analysis, $x^2$ test, multiple response analysis, cluster analysis, ANOVA, and Duncan's multiple range test, using SPSS program. The results were as follows. First, young Chinese male consumers had a high sense of the social instrumentality of appearance, but the tendency to invest time and effort to enhance their looks was still low. Second, on the basis of the social instrumentality of appearance and appearance orientation, young Chinese male consumers were classified into four groups (high involvement group, instrumentality group, orientation group, and low involvement group). Third, the four male consumer groups revealed many significant differences in various cosmetic purchasing behaviors (purchasing items, information sources, product selection criteria, purchasing motives, purchasing locations, store selection criteria, purchasing price, purchasing frequency, and cosmetics improvements). Therefore, the social instrumentality of appearance and appearance orientation are seen as significant variables to effectively segment the Chinese male consumer market. The cosmetics companies targeting young Chinese men need to establish differentiated marketing strategies, considering the characteristics of each segment of the consumer market.

• Journal of the Ergonomics Society of Korea
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• v.29 no.3
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• pp.297-310
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• 2010

The purpose of this study is to investigate the user characteristics in different age groups by investigating the level of satisfaction and preference of design and function of mobile phone. 160 subjects participated in the experiment. Subjects with different ages were selected and divided into four groups: young age group (20 to less than 45), $1^{st}$ middle age group (45 to less than 55), $2^{nd}$ middle age group(55 to less than 65), and elderly group(over 65). A questionnaire was developed based on the previous design guideline, and additional questions were made to test newly developed function and design of the mobile phone. In particular, depth interviews were conducted in order to have a proper response from old subjects who have difficulties in completing written questionnaire. In result, it was found that except for price the major criterion to purchase mobile phone was the design, and the function of phone was the next except for elderly group. In the case of elderly group, the screen size is the first. Statistical results indicated that 37.5% of the young age group, 22.5% of $1^{st}$ middle age group, 22.5% of $2^{nd}$ middle age group and 10.0% of the elderly group preferred the design to function when they purchase mobile phones. Most elderly people were not satisfied with the supplementary function of the mobile phone. The $1^{st}$ middle age group did not know exactly how to use the supplementary service although they were willing to use it. Regarding the emotional preference on the type of phone, the sliding type was preferred most. Current results can be used to anticipate the future trend of mobile phone and design a user-friendly product for the aged population.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.6
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• pp.2709-2734
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• 2020

The growing demand to make wireless data services 5G compatible has necessitated the development of an energy-efficient approach for an effective new wireless environment. In this paper, we first propose a cognitive sensor node (CSN) based game theory for deriving energy via a primary user-transmitted radio frequency signal. Cognitive users' time was segmented into three phases based on a time switching protocol: energy harvest, spectrum sensing and data transmission. The proposed model chooses the optimal energy-harvesting phase as the effected factor. We further propose a distributed energy-harvesting model as a utility function via pricing techniques. The model is a non-cooperative game where players can increase their net benefit in a selfish manner. Here, the price is described as a function pertaining to transmit power, which proves that the proposed energy harvest game includes Nash Equilibrium and is also unique. The best response algorithm is used to achieve the green connection between players. As a result, the results obtained from the proposed model and algorithm show the advantages as well as the effectiveness of the proposed study. Moreover, energy consumption was reduced significantly (12%) compared to the benchmark algorithm because the proposed algorithm succeeded in delivering energy in micro which is much better compared to previous studies. Considering the reduction and improvement in power consumption, we could say the proposed model is suitable for the next wireless environment represented in 5G.

• Korean journal of food and cookery science
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• v.9 no.3
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• pp.230-238
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• 1993

The objectives of this study were to provide the basic data for the consumer education and for the new product development by surveying housewives'demands concerning prepared frozen or refrigerated foods and by surveying industry's practices and opinions concerning new product development. 804 housewives and 14 manufacturing companies of prepared frozen or refrigerated foods were surveyed. Data from housewives were analyzed by using SPSS-X progrm in terms of $x^2$-test, one-way ANOVA, t-test. The results of study are summarized as follows : 1. Frozen dumpling, frozen meat, surimi, ham and sausage were identifed as the most frequently used food items by housewives. The mean storage period for either prepared frozen or refrigerated foods was less than 15 days. 2. Housewives with higher educational background showed the greater concerns in packing and sanitary conditions, convenience in cooking procedures and brand name of the product than their counterparts. 3. Most housewives'purchasing motive for prepared frozen or refrigerated foods was the convenience of the cooking procedures(71.1%). Among the member of family, children(72.8%) specially liked prepared frozen or refrigerated foods. 4. Housewives'demands for prepared frozen or refrigerated foods were 'price reduction'and 'nutrition fortification'. These were in accordance with the companys'opimons. 5. Most wanting new product developments from the housewives perspectives were beverages (37.7%), stir-fried menu items(36.1%), pan-fried menu items(34.0%), stewed menu items(30.3%) and soups(20.4%). In case of stew and soups, the industry did not have a plan to develop those menu items.

• The Korean Journal of Food And Nutrition
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• v.24 no.3
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• pp.376-385
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• 2011

The purpose of this study was to estimate beverage consumption frequency and determine related problems of elementary school students in Chungnam. The survey was conducted with 488 students(boys=230, girls=258) using a questionnaire. The average age of the students was 10.1 years old, thir average height and weight were 145.1 cm and 39.5 kg, respectively and the obesity index was -1.3%. The frequencies for breakfast, lunch and dinner were 5.8 times/week, 6.7 times/week and 6.4 times/week, respectively. Regarding the frequency of snacks, high response rates for 'once/day'(38.3%) and 'none' (30.5%) were observed. Nutrition label on beverages were identified rarely(39.1%), nearly never(19.7%), and never(12.9%). The choice factors in selecting beverage were taste, nutrition, and price. For the type of snack most often consumed, fruit or juice was 25.8%, snack items were 25.2%, bread was 24.8%, dairy products were 7.6%, beverages were 7.0%, noddles were 6.2%, and rice cakes were 3.5%. The kinds of favorite beverages were carbonated drinks(30.3%), functional drinks (24.4%) and milk and yoghurt(23.8%), and main reason for the choice of beverage was "it tastes good". For the point of time that students wanted to drink a beverage, "when I feel thirsty" appeared most often for dairy products and beverages and the next most frequent answer was "after exercise". Therefore it may be necessary to administer systematic nutritional education on perception on nutrition fact label of beverage. And it is thought that plan for proper beverage consumption in elementary school students may be established.

• Korean journal of food and cookery science
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• v.31 no.2
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• pp.153-161
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• 2015

This study was conducted to investigate the consumption practices of ready-to-eat (RTE) foods and to analyze the microbiological hazard of kimbab, a Korean dish, and the most popular of the RTE foods eaten by participants in this study. A questionnaire was distributed to 230 university students who had previously purchased RTE foods, and 224 were collected (response rate: 97.4%). Statistical analyses were conducted on the questionnaires using the SPSS program, and a total of 135 kimbab products were sampled for aerobic plate counts, coliforms, E. coli, E. coli O157:H7, Staphylococcus aureus, Salmonella spp., and Listeria monocytogenes. The results of the analyses are as follows. Kimbab (87.0%), sandwich (86.4%), hamburger (89.8%), lunchbox (81.5%), and sushi (87.4%) were most often eaten immediately after purchasing. Additionally, the results of the microbiological hazards analysis of kimbab showed that the aerobic plate counts were significantly different according to the purchasing price (p<0.01). The coliform levels were significantly different according to the place of purchase (p<0.01) and the major ingredients of kimbab (p<0.05). In addition, Staphylococcus aureus and E. coli were detected in 5.9% and 5.2% of the tested samples, respectively. However, E. coli O157:H7, Salmonella spp., and Listeria monocytogenes were not detected in any of the samples. In conclusion, the manufacturers of RTE foods should apply the HACCP system for food safety.