• Korean Chemical Engineering Research
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• v.52 no.4
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• pp.475-480
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• 2014

In the fields of researches associated with plant layout optimization, the main goal is to minimize the costs of pipelines for connecting equipment. However, what is the lacking of considerations in previous researches is to handle the multi floor processes considering the safety distances for domino impacts on a complex plant. The mathematical programming formulation can be transformed into MILP (Mixed Integer Linear Programming) problems as considering safety distances, maintenance spaces, and economic benefits for solving the multi-floor plant layout problem. The objective function of this problem is to minimize piping costs connecting facilities in the process. However, it is really hard to solve this problem due to complex unequality or equality constraints such as sufficient spaces for the maintenance and passages, meaning that there are many conditional statements in the objective function. Thus, it is impossible to solve this problem with conventional optimization solvers using the derivatives of objective function. In this study, the PSO (Particle Swarm Optimization) technique, which is one of the representative sampling approaches, is employed to find the optimal solution considering various constraints. The EO (Ethylene Oxide) plant is illustrated to verify the efficacy of the proposed method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.703-710
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• 2017

Third-generation (3G) devicesare next-generation devices that allow the use of intelligent services and applications through the Internet of Things (IoT). As the market forexisting smart devices like smartphones and tablet PCs enters the stage of stagnation, the world is now focusing on 3G devices, parts, and services. This study is intended to measure the user's benefits from the various attributes of 3G devices by applying an economic valuation method. For this purpose, the conjoint analysis method was applied, which is one of the representative valuation methods. To apply conjoint analysis, the following attributes of 3G devicesare considered: mode of use, power efficiency, life care, and price. By applying the mixed logit model, the marginal willingness-to-pay(WTP) for each attribute was derived. The results are statistically significant. Respondents showed a high preference or complete flexibility in the mode of use attribute. And they were also found to have WTP for improvements in the life care attribute. The implications and quantitative results of this study are expected to be useful for policies and strategies in the 3G device market.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.2
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• pp.54-68
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• 2015

The advantage of electric taxies is that people who are not familiar with electric vehicle(EV) can have easily experience to ride EV. So, EV taxi would be a reasonable strategy for triggering EV market expansion. However, the EV taxi can be adopted by taxi companies with financial benefits. Therefore the feasibility study should be required by analyzing the cost with the points of view of the taxi company. In this study we suggested the methodology for feasibility study of the EV taxi based on the real taxi data and presented political implication. According to the study result, EV taxies could have economic value under the specific conditions such that the government subsidy is added to the purchase price of the vehicle. Also, the charging time should be used as drivers' rest time or mealtime in order not to consider the loss cost. We suggest that the new feasibility study which compares an EV taxi with other alternative vehicles such as PHEV or with an old EV taxi is needed as the future works.

• Management & Information Systems Review
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• v.28 no.1
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• pp.71-97
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• 2009

In this study, I compare the ability of alternative accounting method for employee stock option to reflect firm value using the Ohlson's(1995) valuation model for 200 firms. The each methods, I compare are employee stock option expense recognition based on the K-GAAP disclosures, and asset recognition at the grant date based on the SFAS No. 123 Exposure Draft: Accounting for stock-based compensation. The model include: (1) a model that uses reported earnings, equity book value, and compensation expense based on the K-GAAP disclosures; (2) a model that uses pro-forma earnings, equity book value and adds a measure of the unrecognized asset arising form granting of employee stock options. Finding form estimating equations that the K-GAAP method for calculating compensation has no explanatory power, and the SFAS No.123 Draft Exposure method for arising asset and fair value compensation better captures than market's perception of the economic impact of stock options on firm values. However, the correlation of employee stock option compensation expense is positive. These results suggest that incentive benefits derived from employee stock option plans outweigh the cost associated with plan. In addition, I couldn't find evidence that company in KOSDAQ that have high growth potential benefit more from employee stock option plan compared to lager, more mature firm in SEC.

• Journal of the Korean Home Economics Association
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• v.38 no.1
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• pp.75-87
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• 2000

The aims of this study are to establish a mode of housing life style that meet the demands of families living in big cities, and the contribute to the development of a better housing life style pattern by considering metropolitan residents' choice of housing and basic concepts of their behavioral patterns. The results of this study were as follows: 1. Value orientation of family life was divided into value orientation of family and value orientation of housing. Value orientation of family was constituted of four factors such as 'harmony', 'leisure and hobbies', 'individual development and its support' , 'education' . Value orientation of housing is constituted of three factors such as 'physical characteristics of house' , '\`environmental condition', 'socio-economic conditions of housing'. The comprehensive life values were constituted of six factors such as 'the importance of communal family', 'the importance of housing decoration and housing life benefits', 'the importance of security and holding environment' , 'the importance of familial harmony', 'the importance of privacy', 'the importance of convenience and natural environment'. Based on three factors, were found to be fine types of value orientation of family life which were 'pursue healthy of family', 'comfort of family', 'clean environment', 'convenient environment', and 'harmonious relationship among family members'. Variables influencing the value orientation of family life were property and price of housing. 2. Consumption propensity when buying house, furniture and durables were constituted of four factors which were propensity to 'beauty', 'fashion', 'tradition and symbol', and 'pragmatic use'. Based on these factors, there were found to be four types of consumption propensity when buying house, furniture and durables which were 'fashion', 'tradition and symbol', 'beauty', and 'pragmatic use'. Variables influencing spending habits were found to be objective social class (SES), types of residence, wife's educational background, and price of housing. 3. Propensity to using space were constituted of three factors which were 'convenience', 'politeness and social grace', and 'housekeeping'. Based on these factors, there were found to be three types of propensity to using space which were 'individuality', 'convenience', and 'politeness and housekeeping'. Variables influencing propensity to use of space were found to be objective social class (SES), wife's educational background, types of homeownership and price of housing 4. According to this study, there were found to be six patterns of housing life style: 1) family that seeks formalist life, 2) family that seeks harmonious life, 3) family that seeks active healthy life, 4) family that combine various factors, 5) family that seeks convenience, 6) family that stresses environment.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.4
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• pp.515-524
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• 2001

Two experiments using growing and finishing pigs (Landrace$\times$Duroc$\times$Yorkshire) were conducted to determine the effects of different levels of vitamins and trace minerals (VTM) on growth performance, nutrient digestibility, carcass characteristics and meat quality of growing-finishing pigs, and to evaluate the suitability of vitamin-mineral levels commonly used in the swine industry in Korea. A total of 120 three crossbred (Landrace$\times$Duroc$\times$Yorkshire) growing (Experiment I: 20.90 0.44 kg average initial body weight) and finishing (Experiment II: 53.55 0.97 kg average initial body weight) were used in 6 and 9 weeks feeding trials, respectively. Pigs were allotted on the basis of sex and weight to 5 treatments with 6 replications per treatment with 4 pigs per pen in a completely randomized block design. Treatments were: 1) control, 2) fat soluble vitamin 200% vs. control, 3) water soluble vitamin 200% vs. control, 4) trace mineral 50% vs. control, 5) trace mineral 200% vs. control. In experiment I, during the overall experimental period (0 to 6 weeks, 21 to 54 kg body weight), ADG of the 200% trace mineral supplemented group was significantly higher than that of the 50% trace mineral supplemented group. There were no significant differences among other the treatments. Digestibility of crude protein was lowest in mineral 50% supplemented group (p<0.05). Calcium digestibility was significantly higher in the 200% fat soluble vitamin supplemented group than in the other treatments (p<0.05). In experiment II, during the overall experimental period (0 to 9 weeks, 54 to 106 kg body weight), growth performance was not significantly affected by dietary vitamin and trace mineral levels. However, increasing level of water soluble vitamins at the level of 200% compared to control had a tendency to improve the overall growth performance. Overall carcass characteristics except for carcass length did not differ among pigs fed the dietary treatments. Loin eye area, pH, drip loss and shear force of meat were not affected by dietary vitamin and trace mineral levels. There was a trend for less fat content (%) in pork when the level of vitamin and trace mineral was increased, but the difference was not significant. Flavor score was the lowest in control and highest in the 200% fat soluble vitamin supplemented group (p<0.05). Juiciness of muscle was lower in the 200% fat soluble vitamin supplemented group than other dietary treatments, except for trace mineral 50% supplemented group (p<0.05). Based on these results, it is suggested that "typical" commercial levels of vitamin and trace minerals used by feed companies in Korea are sufficient to meet requirement for the maximum growth of growing-finishing pigs. Our results suggests that a reduction in trace mineral levels in commercial diets could be considered to reduce feed cost and nutrient excretion with economic and environmental benefits.

• Journal of the Korean Society of Costume
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• v.57 no.2 s.111
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• pp.115-131
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• 2007

By the turn of the century, our society has been gradually more interested in environmental problems than any other time. Ecological change spurred by industrial pollution is occurring beyond the borders of nations, and has emerged as a global issue. Such change is resulting in exhaustion of natural resources and energy, and serious climatic change. In this study, main focus regarding the process of the fashion product design system was placed on the sustainable fashion design of organic cotton as a positive and alternative suggestion. It is expected that the results of this study contribute to the fashion design planning not only for future generation but also for the present time. This study researched on brands that produced their fashion products using organic cotton. The following cases proved to possess sustainability in their product system. The results of this study can be summarized as follows: Firstly, sustainable design in organic cotton products has been a progressive ere-design in 2000s. It is mainly focus concerned with recycling and re-use of materials to protect environment. It is not chemical dependant and takes a particular care in eliminating waste water and energy in the dyeing process. It is an environmentally sustainable design better than all the other design processes. Secondly, it is a design that cares for the common good of society and the global system of fair trading. The fair trading of organic cotton products induced a change in the structure of production system, while defending human rights. It also gave benefits by promoting development in local society and progress in traditional skills. Not to mention that it contributed to building up the concept of transparency in the global economic system. Lastly, the brands emphasize their social responsibility and management ethics to observe environmental policy which is established to protect our nature and people. Their public information reminds customers of the importance of protecting the environment from diverse pollution. Moreover, they hold social events to promote public awareness for environmental Issues. This study dealt only with the organic cotton, a small subset of the subject of sustainable design. It can be extended and applied to various other sustainable fashion design as a solution for global environmental issues.

• Journal of Life Science
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• v.27 no.6
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• pp.726-737
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• 2017

Carotenoids are isoprenoids with a long polyene chain containing 3 to 15 conjugated double bonds, which determines their absorption spectrum. They typically consist of a $C_{40}$ hydrocarbon backbone often modified by different oxygen-containing functional groups, to yield cyclic or acyclic xanthophylls. Much work has also been focused on the identification, production, and utilization of natural sources of carotenoid (plants, microorganisms and crustacean by-products) as an alternative to the synthetic pigment which currently covers most of the world markets. Nevertheless, only a few carotenoids (${\beta}-carotene$, lycopene, astaxanthin, canthaxanthin, and lutein) can be produced commercially by fermentation or isolation from the small number of abundant natural sources. The market and demand for carotenoids is anticipated to increase dramatically with the discovery that carotenoids exhibit significant anti-carcinogenic activities and play an important role in the prevention of chronic diseases. The increasing importance of carotenoids in the feed, nutraceutical food and pharmaceutical markets has renewed by efforts to find ways of producing additional carotenoid structures in useful quantities. Because microorganisms and plants synthesize hundreds of different complex chemical carotenoid structures and a number of carotenoid biosynthetic pathways have been elucidated on a molecular level, metabolic and genetic engineering of microorganisms can provide a means towards economic production of carotenoid structures that are otherwise inaccessible. The aim of this article is to review our current understanding of carotenoid formation, to explain the perceived benefits of carotenoid in the diet and review the efforts that have been made to increase carotenoid in certain microorganisms.

• Journal of Life Science
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• v.28 no.1
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• pp.130-139
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• 2018

In ancient times, horse racing was done in ancient European countries in the form of wagon races or mountain races, and wagon racing was adopted as a regular event at the Greek Olympic Games. Thoroughbred horse has been bred since 17th century by intensive selective breeding for its speed, stamina, and racing ability. Then, in the 18th century, horse racing using the Thoroughbred species began to gain popularity among nobles. Since then, horse racing has developed into various forms in various countries and have developed into flat racing, steeplechasing, and harness racing. Thoroughbred racehorse has excellent racing abilities because of powerful selection breeding strategy for 300 years. It is necessary to maintain and maximize horses' ability to race, because horse industries produce enormous economic benefits through breeding, training, and horse racing. Next-generation sequencing (NGS) methods which process large amounts of genomic data have been developed recently. Based on the remarkable development of these genomic analytical techniques, it is now possible to easily carry out animal breeding strategies with superior traits. In order to select breeding racehorse with superior racing traits, the latest genomic analysis techniques have to be introduced. In this paper, we will review the current efforts to improve race performance for racehorses and to examine the research trends of genomic analysis. Finally, we suggest to utilize genomic analysis in Thoroughbred racehorse and Jeju horse, and propose a strategy for selective breeding for Jeju horse, which contributes job creation of Korea.

• Journal of Preventive Medicine and Public Health
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• v.31 no.2 s.61
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• pp.199-214
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• 1998

This study was undertaken to explain weight control behavior and intention of obese children and adolescents as measured by the elements of the health belief model. A total of 732 obese students from 28 schools in Seoul metropolitan area and their mothers were assessed with a self-administered questionnaire. The analyzed results are as follows; 1. Among obese students, 45.3% of male students and 57.2% of female students, a significantly higher portion than male students, reported that they had tried to lose weight within the recent year. Exercise was the most frequently used method to lose weight followed by diet control, drug use, and specialized clinic visits, in descending order. 2. Male students were more likely to try to lose weight if they perceived a low threat level and their mother had a job, and female students were more likely to try to lose weight if they were younger in age, perceived a low threat level and had strong external motivating factors. 3. Female students showed a significantly higher level of intention to obesity control than male students, and the intention level of their mothers also showed the same trend. 4. In male students, the degree of weight dissatisfaction, weight control experience, the level of obesity related beliefs of students, the educational level of the mother and economic status of the family were significant predictors of intention to obesity control, and in females, age, the level of obesity related beliefs of students and intention of their mothers were significant. In the mothers of male students, obesity index of students, age of the mother and the level of obesity related beliefs of the mother were significant predictors of intention of the mother, and in the mothers of female students, obesity index of students, occupational status of the mother and obesity related beliefs of the mother were significant. 5. According to the path model of intention to obesity control, the degree of weight dissatisfaction had the most powerful effect in male students, and perceived net benefit level was the most important variable in female students. Since the weight control behavior and intention of obese students were more predictable by the degree of weight dissatisfaction than the obesity index, we can conclude that only the students dissatisfied with their weight are well motivated for obesity control. There can be a discrepancy between the mother and her child's beliefs and intention status(especially in male students), so the therapists should also assess the student's opinion as well as the mother's. In female students, the perceived net benefit level wag the most important predictor of intention to obesity control, therefore the intervention program should pay particular attention to the positive benefits of weight control rather than negative aspects(threats) of obesity.