• Journal of Animal Science and Technology
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• v.44 no.3
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• pp.271-278
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• 2002

This experiment was conducted to investigate the genetic and non-genetic factors affecting kid survivability in goats from birth to 90 days of age. The purebreds had lower survivability than the crossbreds, with significant (p$<$0.05) difference amongst themselves for the age of 31 to 90 days. The locational effect on survivability was insignificant for all the periods except 16 to 60 days (p$<$0.05) of age. The sex and birth type also had significant (p$<$0.05) effect on survivability for all the periods except 0 to 7 days of age. The survivability was found to be significantly (p$<$0.05) higher for kids born in summer season followed by those born in winter and rainy season. Milk produced by the does were significantly (p$<$0.05) affected on the survivability of kids during the period from 16 to 60 days of age. The survivability of kids were highest and lowest having milk yield of doe found to be 400-600 g/day and 80-200 g/day, respectively. Birth weight had significant (p$<$0.05) effect on survivability for all the stages of growth up to 90 days of age. Survivability was positively correlated with does’ milk yield as well as kids birth weight. Interactions of sex with location or birth type were significant (p$<$0.01 and p$<$0.05, respectively) though interaction between sex and genetic group was insignificant.

• Journal of Energy Engineering
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• v.23 no.2
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• pp.28-34
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• 2014

Automatic transmission fluid (ATF) is used for automatic transmissions in the vehicle as the characterized fluid. Recently, the vehicle manufacture usually guarantee for fluid change over 80000~100000 km mileage or no exchange, but most drivers usually change ATF below every 50000 km driving in Republic of Korea. It can cause to raise environmental contamination by used ATF and increase the cost of driving by frequently ATF change. In this study, we investigate the various physical properties such as flash point, fire point, pour point, kinematic viscosity, cold cranking simulator, total acid number, and metal component concentration for fresh and used ATF after driving (50000 km, 100000 km). The result showed that the total acid number, pour point, Fe, Al and Cu component had increased than fresh ATF, but 2 kind of used oil (50000 km and 100000km) had similar physical values and metal component concentration.

• Journal of Digital Convergence
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• v.20 no.2
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• pp.367-373
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• 2022

The purpose of this study is to derive the factors for purchasing a meal kit in their 20s and 30s and analyze the purchasing behavior from which factors they want to buy a meal kit in each lifestyle type. The first methodology of this study is inducing 7 factors derived from previous research on purchasing a meal kit. The second is the in-depth interview on 3 male and 3 female participants with clear purchasing criteria. As a result of the study, meal kit buyers in their 20s-30s evaluated the importance of purchasing factors in the order of quality, convenience, and taste on average in the survey. In in-depth interviews, more than half answered that they could be satisfied with the experience of using the meal kit at least freshness met. In conclusion, MZ generation meal kit consumers have a high rate of pursuing rational consumption. This study is valuable in understanding the priorities of the MZ generation's meal kit purchasing attributes and examining lifestyle type's purchasing behaviors.

• Journal of the Korean Society for information Management
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• v.24 no.2
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• pp.161-179
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• 2007

As increasingly diverse kinds of information materials are available on the Internet, it becomes a challenge to define an adequate level of metadata provision for each different type of material in the context of digital libraries. This study explores issues of metadata provision for a particular type of material, statistical tables. Statistical data always involves numbers and numeric values which should be interpreted with an understanding of underlying concepts and constructs. Because of the unique data characteristics, metadata in the statistical domain is essential not only for finding and discovering relevant data, but also for understanding and using the data found. However, in statistical metadata research, more emphasis has been put on the question of what metadata is necessary for processing the data and less on what metadata should be presented to users. In this study, a case study was conducted to gauge the status of metadata provision for statistical tables on the Internet. The websites of two federal statistical agencies in the United States were selected and a content analysis method was used for that purpose. The result showing insufficient and inconsistent provision of metadata demonstrate the need for more discussions on statistical metadata from the ordinary web users' perspective.

• Journal of Periodontal and Implant Science
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• v.24 no.1
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• pp.26-38
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• 1994

The purpose of this study was to evaluate the effects of citric acid and fibrin on the regeneration of periodontal tissues using 4 normal canines of five dogs. Mucoperiosteal flap was raised and experimental defects were made at the buccal root surfaces about $4{\times}6mm$ in length. The denuded root surfaces were covered using coronally repositioning technique after root planing alone at left lower canine, root planing plus fibrin at rigth lower canine, root planing plus citric acid at left upper canine or root planning plus citric acid and fibrin at right upper canine. All of the specimens were tangentially cut(about $3-5{\mu}m$)and available for histologic analysis 1, 3, 7, 14 and 21 days after operations. The results were as follows : At one' day after operations, the amounts of fibrin were similarly higher in the group I, II and III than control group and at 3 days after operations, the apical migrations of the long junctional epithelium were prominent in the control group and group I. At 7 days after operations, the fibrin meshworks of each group were partly changed to the collagen fibers and characteristics of the fibers were almost collagenous rather than fibrinous at 14 days after operations and at 21 days after operations, the orientation of collagen fibers were partly normal in group II and group III, but not in control group and group I. Root resorptions were visible in group II and group III at 14 days after operations and more significant in group II than group III at 21 days.

• Design & Manufacturing
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• v.11 no.2
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• pp.1-8
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• 2017

In this study, we applied microcellular foaming injection molding process to improve the performance of system air-conditioner drain fan which had been produced by injection molding process and studied the optimization of process conditions through 6-sigma process and response surface method (RSM) to reduce weight and deformation of products. Additive type, melt temperature, mold temperature, and injection screw shape were selected as the factor affecting the weight and deformation of the products by carrying out analysis of trivial many through ANOVA and design of experiment (DOE) method. Among the effect factor, we set the addictive type to Long G/F and screw shape to foaming screw which had the highest level of weight reduction and deformation reduction. The amount of foaming agent gas was set at 60 ml, which was the limit beyond which the weight of product did not decrease any more. For melt temperature and mold temperature, we studied the conditions where both weight and deformation were minimized using the RSM. As a result, we set the melt temperature to $250^{\circ}C$, fixed mold temperature to $20^{\circ}C$, and moving mold temperature to $40^{\circ}C$. The improvement effect was analyzed by appling the selected optimal conditions to the production process using the microcellular foaming injection molding. The results showed that the mean weight of product was measured to be 1,420g which was 19% lower than that measured in the current process. The standard deviations of the weights were found to be similar to those in the current process and it showed a low dispersion. The mean deformation was measured to be 0.9237mm, which represented a 57% reduction compared to the mean deformation in the current process, and the standard deviation decreased from 0.3298mm to 0.1398mm. Moreover, we analyzed the process capability for deformation, and the results showed that the short-term process capability increased from 2.73 to 6.60 which was even higher than targeted level of 6.0.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.175-182
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• 2017

In light emitting diode (LED) chip packaging, wire bonding is an important process that connects the LED chip on the lead frame pad with the Au wire and enables electrical operation for the next process. The wire bonding process is divided by two types: thermo compression bonding and ultrasonic bonding. Generally, the wire bonding process consists of three steps: 1st ball bonding that bonds the shape of the ball on the LED chip electrode, looping process that hangs the wire toward another connecting part with a loop shape, and 2nd stitch bonding that forms and bonds to another electrode. This study analyzed the factors affecting the LED die bonding processes to optimize the process capability that bonds a small Zener diode chip on the PLCC (plastic-leaded chip-carrier) LED package frame, and then applied response surface analysis. The design of experiment (DOE) was established considering the five factors, three levels, and four responses by analyzing the factors. As a result, the optimal conditions that meet all the response targets can be derived.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.1046-1057
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• 2017

Country-specific emission factors should be developed and used instead of IPCC defaults to improve national GHG inventories to Tier 2 and above. Since the country-specific emission factors depend on the type of energy source, energy process, and time trend, identifying the value of each energy source is an important part of building an accurate inventory. In this study, calorific value and carbon emission factor for petroleum energy sources on the basis of calorific value conversion standard for energy source, which are notified in Korea, are collected by 2013 and 2016, and calorific value, carbon content and carbon emission factor And a comparative analysis was conducted. In addition, net calorific values and carbon emission factors calculated for each petroleum based energy source are compared with those shown in 2006 IPCC Guideline.

• Journal of Industrial Convergence
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• v.20 no.2
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• pp.71-78
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• 2022

This study intends to present a desirable vision so that students can focus on their studies and adapt to the dental hygiene major education perceived by dental hygiene students in un-contact lecturess situations by preparing measures to increase student satisfaction with the dental hygiene department. Data collection was conducted using a self-reported questionnaire from students in the dental hygiene department at universities in Seoul, Chungcheong, and Gangwon from June 20 to August 19, 2021. Variables according to the general characteristics of the subjects were analyzed using t-test and one-way ANOVA, and the post hoc test was verified by Tukey. The correlation between variables was Pearson's correlation, and the factors affecting dental hygiene and students' major satisfaction were multiple regression. The self-directed learning ability of dental hygiene students was 3.57 points, learning immersion was 3.02 points, and major satisfaction was 3.54 points. Dental hygiene students were found to have higher major satisfaction with higher grades, higher college life satisfaction, and higher learning immersion and self-directed learning ability. Therefore, it was found that systematic program development and application is necessary to improve major satisfaction in difficult circumstances due to COVID-19.

• The Journal of Engineering Geology
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• v.33 no.2
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• pp.323-334
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• 2023

The vast volumes of data that are generated during site characterization and associated research for the disposal of high-level radioactive waste require effective data management to properly chronicle and archive this information. The Swedish Nuclear Fuel and Waste Management Company, SKB, established the SICADA database for site selection, evaluation, analysis, and modeling. The German Federal Company for Radioactive Waste Disposal, BGE, established ArbeitsDB, a database and document management system, and the ELO data system to manage data collected according to the Repository Site Selection Act. The U.K. Nuclear Waste Services established the Data Management System to manage any research and survey data pertaining to nuclear waste storage and disposal. The U.S. Department of Energy and Office of Civilian Radioactive Waste Management established the Technical Data Management System for data management and subsequent licensing procedures during site characterization surveys. The presented cases undertaken by these national agencies highlight the importance of data quality management and the scalability of data utilization to ensure effective data management. Korea should also pursue the establishment of both a data management concept for radioactive waste disposal that considers data quality management and scalability from a long-term perspective and an associated data management system.