• 한국정밀공학회지
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• 제27권12호
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• pp.92-98
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• 2010

The design of press bonding tool in LCD module equipment is a very complex and difficult task because many design able variables are involved while their effects are not known. It takes longtime experiments and much expenses to verify the effects of these design variables. However the optimization of bonding tool using OLB(outer lead bonding) and PCB Bonding is a very important problem in LCD manufacturing process, so much design efforts have been made for improving the bonding tool performance. In this paper, a reasonable and fast process which gives optimized solution under the design requirements has been presented. Both analytical and statistical methods are employed in this process. A reliable analytic model using experiment-oriented FE analysis can be obtained, in which the regression equations that predict the tool efficiency from various DOE method are found. Improvement of tool efficiency could be estimated by the regression equations using meaningful factors converged by RSM(Response Surface Method). With this process a reasonable optimized solution that meets a variety of design requirements can be easily obtained.

• Communications for Statistical Applications and Methods
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• 제16권6호
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• pp.979-987
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• 2009

In this study, we compare the assessments made by self, peer and instructor in a statistics course. The goal is to investigate the following two questions: (1) Is it reasonable or fair to expect students to be responsible for assessing the work of their colleagues and themselves? (2) What are students' opinions about the learning effect after they participate in the assessment process? As part of the study investigating these questions, we designed a prototype for a Web-based assessment tool and a procedure to apply the assessment techniques in a statistics course. In addition, we collected and analyzed the data produced in the assessment processes from students and the instructor. The analysis results are summarized as follows: First, self assessment was not accord with instructor assessment, but peer assessment was similar to the assessment by instructor. This result reflected that it is reasonable or fair to expect students to be responsible for assessing the work of their colleagues. Second, peer assessment of their colleagues successfully helped students increase their understanding of the course, and the students increased their skills in the actual assessment process by assessing the work of their colleagues. Finally, many students indicated a high interest level on the assessments.

• 대한수의학회지
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• 제24권1호
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• pp.83-90
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• 1984

In the evaluation of anthelmintic efficacy by fecal egg counts for cattle naturally infected with helminths, the reasonable technique of fecal egg counts and the reliable guidelines were determined as follows; 1. Modified technique of Harashigeru and Kim's sedimental tube was the most reasonable in fluke egg counts. 2. Universal egg counting technique was preciser than McMaster egg counting technique and was lower in coefficient variation. 3. Fecal egg counts of pretreatment should be carried out twice and mean of the epg should be calculated. 4. Fecal egg counts of posttreatment should be carried out 3 times and established at suitable intervals in consideration of anthelmintic mechanism and withdrawal days of anthelmintics. 5. If nematodal eggs are not found by UECT in posttreatment, direct flotation method should be carried out. And if positive, this epg was calculated at 20 (factor of UECT; $40{\times}1/2$).

• 한국식생활문화학회지
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• 제18권6호
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• pp.515-526
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• 2003

The object of this study was to investigate the relationship between the eating habits of high(4th, 5th, 6th) grade elementary school students and parental behavior characteristics(affection, rational guidance, overprotect and neglect). The parenting behavior scale and demographic variables, eating habits and food frequency were administered to the subjects. In this investigation, the subjects were 396 boys and 337 girls in Chunju city in Korea, 50.1% of the mothers was in the age from 35 to 39 years and 57.8% of the mother had an occupation. Data were analyzed by using a SPSS PS package. Significant differences and correlation among variables were determined by the frequency, $x^2-test$ and pearson's correlation coefficient. Eating habits was significantly influenced by mother's employment status, but was not affected by the levels of mother's education and income. Parental behavior characteristics was significantly related to the children's snacks habits(p<0.05, p<0.01), but have no connection with dietary habits and the eating out. The survey revealed higher percentage of the children who had taken affectionate, reasonable and positively reinforced child care, answered they enjoy meals and the other groups answered they did not. Also frequency of having soup, green vegetables, fruits, dairy products had positive relationship with affective, reasonable rearing attitude, but negative relationship with neglective rearing attitude. And the survey showed children who were reared in overprotect had chocolate, candy and the like in large quantities.

• Food Quality and Culture
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• 제3권2호
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• pp.74-81
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• 2009

This study investigated consumers' recognition on shelf life of health functional foods to set up their rational expiration date. For this study 107 male and female adults aged 20 to 59 years were randomly selected as major consumers of health functional foods. And their data were analyzed with SPSS 17.0. The questionnaire included questions asking a consumer's recognition on the shelf life of health functional foods and how to treat health function food passing its shelf life. In this study, the consumers were found to pay attentions considerably to the shelf life. But most of them did not know an accurate meaning of the shelf life of health functional food and mistook it for expiry date. In addition, the consumers doubted safety of health functional foods passing the shelf life. Therefore, education for consumers about an accurate meaning of the shelf life was needed. The results of this study were considered to be helpful to set up a reasonable expiration date for health functional food.

• 한국도로학회논문집
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• 제19권2호
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• pp.55-65
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• 2017

PURPOSES : This study aimed to analyze the experimental and numerical behavior of warm mix asphalt pavement prepared using steel slag and RAP and to conduct economic analysis of pavement construction. METHODS : For developing high performance asphalt pavement, we performed three evaluations: fundamental analysis, experimental testing, and 3D finite element analysis. In particular, 3D finite element analysis was conducted on several pavement structures by adopting the results of experimental tests. RESULTS : Through the various evaluations, it was established that steel slag was effective for use as asphalt mixture aggregate. Moreover, asphalt mixture constituting steel slag and RAP demonstrated higher performance behavior compared with conventionally used asphalt mixture. Furthermore, based on the 3D FE modeling, we established that the developed asphalt pavement constituting steel slag and RAP can be utilized for thin layer pavement with comparable performance behavior. CONCLUSIONS :Warm mix asphalt pavement prepared using steel slag and RAP is more competitive and economic compared to hot-mix asphalt pavement. Moreover, it can be applied for preparing thin layer asphalt pavements with reasonable performance. The developed warm mix asphalt pavement prepared using steel slag and RAP can be an alternative pavement type with competitive performance based on the reasonable economic benefit it provides.

• Journal of Biosystems Engineering
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• 제38권4호
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• pp.264-269
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• 2013

Purpose: This study was carried out to develop a classification index and grade levels to rate agricultural heaters for energy efficiency classification. Methods: The classification index was developed mainly by taking simplicity of calculation and easy access to relevant data into consideration. The grade levels were developed on the basis of a 5-grade classification system in which graded heaters are to be normally distributed over the grades. The value of each grade level were determined in terms of the classification index values calculated using the published performance data of agricultural heaters tested at the FACT in Korea over the past 12 years. Results: The thermal efficiency of agricultural heaters based on the enthalpy method was proposed as a reasonable classification index. The grade levels were proposed in equation form for three types of agricultural heaters: fossil fuel heaters, wood pellet heaters and wood pellet boilers. A reasonable energy efficiency classification of agricultural heaters could be performed using the proposed classification index and grade levels. Conclusions: It is expected that energy saving programs will be extended to agricultural machines in the near future. The classification index and grade levels to rate agricultural heaters for energy efficiency classification were developed and proposed for such near future to come.

• International Journal of Aeronautical and Space Sciences
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• 제2권2호
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• pp.95-107
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• 2001

This paper is devoted to the parameter optimization of unmanned aerial vehicle's (UAV) flight control laws. Optimization procedure is based on the ideas of mixed $H_2/H_{\infty}$ control of multi-model plants. By using this approach, some partial $H_2$-terms defining the performance of nominal and parametrically perturbed Flight Control System (FCS) responses to deterministic command signals in stochastic atmosphere as well as $H_{\infty}$-terms defining robustness of the FCS can be incorporated in the composite cost function. Special penalty function imposed on the location of closed-loop system's poles keeps the speed of response and oscillatory properties for both nominal and perturbed FCS in reasonable limits. That is the reason why this procedure may provide reasonable trade-off between the performance and robustness of FCS that are very important especially for UAV. Its practical importance is illustrated by case studies of lateral and longitudinal control of small UAV.

• 환경영향평가
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• 제18권5호
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• pp.313-319
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• 2009

A complex maritime resort combined marina and with course of Korea is required to improve international tourism competitiveness by taking advantage of her environmental favorable circumstances. The development of tourism, however, is focused on land-oriented that incurred lower tourism efficiency and international tourism competitiveness. In addition, the regulation of "Preliminary environmental assessment for golf courses" by the Ministry of Environment is emphasized on land geography and geology that can cause damage of tourist attractions in an island region. In particular, the development of 6th or 7th ridges in mountainous island region within 2km from the sea, that holds scenic and academic value, can go against environment-friendly by geographical and geological damage. According to the regulation for consultation for golf courses and forestry is to preserve regional ecosystem over 6th ridge, but it cannot be applicable to island region because that can form excessive slopes where marine ecosystem is required to be maintained. It, therefore, can be desirable that the development of over 6th ridge in an island region. It is suggested that continuous comparative studies of geographical and geological characteristics between land and island region will be carried on to establish feasible and reasonable development model so that balanced development of land and island, and versatile international environment-friendly maritime resort can be achieved and developed.

• 한국안전학회지
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• 제19권3호
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• pp.70-77
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• 2004

A Reasonable lighting should be provided for doing night work. All works far construction site can be exposed to potential hazard at night work The purpose of this study is to provide a standard of the lighting against accidents due to insufficient lighting at site. one pilot tea one at building work site, one at mad work site of it have been conducted for figuring out illumination change depending worker's activity direction, using lux checker to show it as numerical indication. The direction are changed with a range of 30, 60, 90, and 135 degree to be checked at site. Tests results show that $10\%\;and\;15\%$ of lighting could be decreased by changing the working direction of works at site. Therefore, steep slope place, cave work and backside of structural elements such as a column, deep beam should be considered for keeping sufficient and reasonable lighting. It is found that $50\%more$ illumination Lux needs f3r civil work than for building work.