• Journal of the Korean GEO-environmental Society
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• v.11 no.8
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• pp.73-82
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• 2010

The GFRP(Glass-Fiber Reinforced Plastic) pipe is designed to behave safely against the external forces and to secure stability of deformation and settlements of pipe, since it is laid under the ground. In this study, the evaluation for the pressure stability was carried out by performing the laboratory experiments to figure out the mechanical properties of Glass-Fiber Reinforced Plastic pipe, take a theoretical approach, and suggest the mechanical properties necessary for the analysis and design of GFRP. Numerical analysis is also conducted to evaluate on the field application through the comparison concerning relations between deformation and differential settlement in the GFRP and hume pipes when all and half sections are under the surcharge load.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.7
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• pp.885-891
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• 2004

To evaluate the feasibility of using sperm-mediated gene transfer (SMGT) for carrying foreign gene into chicken oocyte, a reporter gene, CX-EGFP, was used in this study. The reporter gene was first mixed with liposome or liposome-like compound and the mixtures were further combined with ejaculated cock spermatozoa. The spermatozoa treated with liposome and CX-EGFP mixture was subsequently coincubated with DNaseI to remove the extra DNA which insured the authenticity of positive signals. The treated sperms were then subjected to transgene (reporter gene) existence analysis and artificial insemination of laying hens. Obtained results indicated that the spermatozoa were able to take-in the foreign DNA; which was confirmed by polymerase chain reaction and Southern blot analysis. In the following experiment, fresh ejaculated sperms were mixed with CX-EGFP-liposome or CX-EGFP-liposome-like complex then used for artificial insemination of each of six laying hens. Eggs laid between day-3 and day-7 post insemination were collected. Newly hatched chicks, two out of 53 from CX-EGFP/liposome treated group and two out of 21 from CXEGFP/liposome-like treated group, were proven to be transgenic. This study suggests that SMGT is a powerful method for generating transgenic chickens.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.1
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• pp.1-11
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• 2002

Flow of fluid has been studied in various fields of fluid engineering. To hydraulic engineers, the unsteady flow such as pulsation and liquid hammering in pipes has been considered as a serious trouble. So we are supposed to approach the formalized mathematical model by using more exact momentum equation for fluid transmission lines. Most of recent studies fur pipe line have been studied without considerations of variation of viscosity and temperature, which are the main factors of pressure loss causing the friction of fluid inside pipe line. Frequency response experiments are carried out with use of a rotary sinusoidal flow generator to investigate wave equation take into account viscosity and temperature. But we observed that measured value of gains are reduced as temperature increased. And it was respectively observed that the measured value of gains are reduced and line width of gain is broadened out, when temperature was high in the same condition. As we confessed, pressure loss and phase delay are closely related with the length, diameter and temperature of pipe line. In addition, they are the most important factors, when we decide the momentum energy of working fluid.

• Journal of the Korean Institute of Rural Architecture
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• v.10 no.3
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• pp.9-18
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• 2008

The study was intended to suggest the design alternatives of rural village community center based on the design directions which were derived from the previous research, and to evaluate the alternatives by rural residents. The previous research was carried out to grasp the conditions and user's needs of rural village community center. The subjects were 100 residents who lived in rural area in Chonlabukdo. The interview was carried out using a questionnaire with model and isometrics of two alternatives, which showed floor plan and building shape. The subjects evaluated positively both of two alternatives, but slightly more preferred alternative | because of a spacious diningroom and an indoor toilet. The size of a livingroom and entrance, indoor toilet space/location, storage space and deck were significant elements in two alternatives according to t-test. They responded that both of indoor and outdoor toilet should be planned in rural village center. Also, each toilet and room for man and woman should be separated. Entrance space should be enough to take on/off their shoes in a sitting position and deck space was planned to intermediate between indoor and outdoor space.

• Journal of Engineering Education Research
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• v.15 no.6
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• pp.80-85
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• 2012

This study investigates significant factors regarding college freshman engineering students and analyses each factors influence on student satisfaction in the College of Engineering core curriculum. We carried out a survey targeting 505 students who completed their fundamental education for major course learning in the 2011 academic year while attending one college in Gwangju and ruled out inadequate respondents. A total sample size 437 students were analyzed. The seven independent variables are academic fees, academic term period, academic environment of the classroom, learning material content, time of lecture, student sincerity and student need for the program. The dependent variable is fundamental education satisfaction level. As a result of multiple regression analysis, the following factors were found to be significant in the following order: learning material content, time of lecture, student sincerity, student need for the program, academic fees and academic environment of the classroom. On the other side academic term period was not significant. For improving fundamental education satisfaction, there is a need for prudent consideration regarding learning material development and lecture times. Also further investigation should take place for policies necessary for increasing learner motivation and sincerity, and expand appropriate conditions for learners to become self-aware of the education they need within their major.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.10
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• pp.154-160
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• 2001

For major structural components periodic inspections and integrity assessments are needed for the safety. However, many flaws are undetectable because sampling inspection is carried out during in-service inspection. Probabilistic integrity assessment is applied to take into consideration of uncertainty and variance of input parameters arise due to material properties and undetectable cracks. This paper describes a Probabilistic Fracture Mechanics(PFM) analysis based on the Monte Carlo(MC) algorithms. Taking a number of sampling data of probabilistic variables such as fracture toughness value, crack depth and aspect ratio of an initial surface crack, a MC simulation of failure judgement of samples is performed. for the verification of this analysis, a comparison study of the PFM analysis using a commercial code, mathematical method is carried out and a good agreement was observed between those results.

• Fire Science and Engineering
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• v.22 no.5
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• pp.125-136
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• 2008

Corruption of the bureaucratic society can cause the whole society to corrupt and it can also increase public expense gradually because of the civil society's distrust of the administration. Throughout experience of front-line firefighters, this study lets the entire firefighters take an interest in increasing integrity and make it the primary assignment of fire administration. It is the most important to find out the illogical systems and try to improve them in order to solve the increasingly secret and sophisticated forms of corruption completely. The purpose of this study is to show the ways to improve firefighters' integrity by analyzing and pointing out the main factor and the realities of corruption of firefighters.

• Journal of Korean Home Economics Education Association
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• v.15 no.4
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• pp.23-35
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• 2003

The purpose of this research is to analyse the composition of theories and practical activities in clothing and textiles in Technologyㆍ Home economics textbooks in the 7th National Curriculum and find out learning requirement of students in the area. For this research, a survey was conducted using questionnaires with 280 high school students living in Daegu and the rate of response was 78.9%. The results of this study are as follows. 1. After analysing the curriculum of Practical Arts subject in elementary school and Technology´ Home Economics subject in secondary school, we could find out that more emphasis is put on practical activities in elementary school and high school. On the other hand, theories are considered more important in middle school. 2. Students have similar preference both for theories and for practical activities as a way of learning in class and show positive responses to practical activities unless they´re giving too much pressure as a part of performance test. 3. According to their learning requirement. several teaching-learning contents in clothing and textiles in Technology Home economics are selected such as materials,. clothes designs, how to set dressed well, how to make a reasonable purchase on clothes, and the process of manufacturing various clothes, etc. Therefore it would be desirable to provide the students with the learning opportunity to the extent where even the students who haven´t chosen the selected-advanced course can take part in class actively.

• Explosives and Blasting
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• v.17 no.4
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• pp.32-50
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• 1999

This study deals with interface charactristics of tube and tubesheet of the nuclear steam generator by the explosive expansion in order to take advantage of optimum expansion ratio, pull-out strength and leakage tightness and improvement of the resisitance on the stress corrosion cracking for low residual stress. The paper also show the relationship between roll, hydraulic and explosive expansion. The results obtain are as follows (1) Because of the explosive bonding is to use the high speed pressure and energy by the explosive, workability is good, bonding region is homogenous (2) Expansion ratio is 2.7%, Pull-out strength 850kg, Leakage strength $500kg/cm^2$. Clearance gap is 10~30mm in case of explosive expansion and interface structure of the tube and tubesheet is optimum condition. (3) As the transition region of the explosive expansion is inactive, the resistance of the stress corrosion cracking is increases 30~40% compare to the roll and hydraulic expansion.

• Journal of the Korean Society of Food Culture
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• v.30 no.4
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• pp.447-456
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• 2015

The purposes of this study were to determine health consciousness and eating habits of dining business owners from Seongnam city. To figure out their health levels, this study focused on quality of sleep, current state of health, health care, smoking, drinking, regular exercise, working hours, dietary behavior pattern, dietary habits, and food intakes patterns. Out of 200 subjects, 104 (52.0%) were males and 96 (48.0%) were females. Their average age was 46.60. For education level, a majority of males graduated from college, whereas a majority of females graduated from high school. Average combined ratios of overweight and obese were 62.5% for males and 25% for females. A majority worked less than 3 years in the dining business area, but 37% of subjects worked more than 10 years. Average health level was favorable, but 38.9% of subjects had hypertension. Males' percentages for smoking and drinking were higher than those of females. Regular physical activity was high, but regular exercise rate was low. Males' average eating speed was faster than that of females and had low scores for desirable eating habits. The study shows that local business owners need to take care of their health.