Stearoyl-CoA desaturase (SCD1) gene plays important role in fatty acid composition. In order to find marker-assisted selection (MAS) for improving the economic trait, this study was performed to identify the 878T>C single nucleotide polymorphism (SNP) on SCD1 gene. Three genotypes (CC, CT, and TT) were detected in 878T>C SNP of SCD1 gene from 103 Hanwoo population by polymorphism chain reaction-restriction fragment length polymorphism (PCR-RFLP) and economic traits were analyzed by general linear model. The frequency of allele C and T was 0.534 and 0.466, also the genotype frequency of CC, CT and TT was 0.252, 0.563, and 0.184, respectively in the Hanwoo population. The TT genotype of SCD1 gene showed a significantly higher measures (p<0.05) of carcass weight (CW) than CT, CC genotype. No significant association was detected between genotype and other economic trait (marbling, backfat thickness, and longissimus muscle area) in this study. The results revealed that SCD1 gene 878T>C SNP could be useful for effective MAS to increase the economic quality in Hanwoo population.

This study was carried out to investigate artificial insemination (AI) failure status and frozen semen characteristics in Korean proven bulls‘ number (KPN) semen used for AI of Hanwoo cows in Gangwon East region (Gangneung, Donghae, Taebaek, Samcheok, Sokcho, Yangyang, Goseong). Among semen used for AI, AI failure rate showed lowest at KPN506 (27.6%), whereas highest at KPN593 (77.2%). Correlations of AI failure in between Korean proven bulls semen and cows was 0.2941, which means that AI failure rate of Korean proven bulls semen may have respectable effect on reproduction of Hanwoo cow. In addition, present study was conducted to investigate spermatozoal viability rate, ruptured acrosome rate and active mitochondria in frozen Korean proven bulls semen with flow cytometry. The semen of KPN593 showed significantly (p<0.05) higher viability rate in KPN593 (30.49%) than that in KPN637 (37.34%). Furthermore, percentage of ruptured acrosome was lower in KPN637 as 21.37% than in KPN637 (21.37%), but it was not statistically significant. In conclusion, these results indicate that choice of Korean proven bulls semen may correlate positively with conception rate in Hanwoo cow. Therefore, KPN with high AI failure rate might be avoid to increase conception rate and characteristics of frozen semen might be evaluated before its use for AI.

Myopalladin (MYPN) is an important expression gene associated with regulation of Z-line structure in muscle and maintains sarcomeric integrity. In this study, we investigated the association between MYPN A1795G SNP (single nucleotide polymorphism) and carcass traits (LMA, longissimus muscle area; CW, carcass weight; BF, backfat thickness; MS, marbling score) in Korean cattle. The MYPN A1795G SNP was genotyped in 212 steers and analyzed the associations with carcass traits by PCR-RFLP (Restriction fragment length polymorphism) method. The allele frequencies were 0.566 for G allele and 0.434 for A allele. And the genotype frequencies of GG, GA, and AA genotype were 32.1%, 49%, and 18.9%, respectively. Association analysis indicated that the A1795G SNP of MYPN gene showed a significant association with LMA (p<0.05). The steers with GG genotype had higher LMA than those with the genotypes AA. But no significant associations were observed in other carcass traits (CW, BF, MS). The steers with the GG genotype showed higher CW and BF than those with the genotypes AA and GA. These results suggest that the A1795G SNP of the MYPN gene is associated with LMA and may be useful for candidate marker-assisted selection to increase the levels of LMA in Korean cattle.

Enforcement of the beef traceability system can block the sale of imported beef disguised Hanwoo and help customers to know detailed information of the Hanwoo beef while purchase. This study was carried out to investigate the possibilities of identifying DNA upon various ripening and roasting methods (soy sauce, gochujang sauce, 10% vinegar, 10% coke, 10% Cheongha, 10% Soju, completely burned out, raw, normal roasted, dried, and boiled) employed for beef traceability system. Completely burned out meat could not yied useful DNA in the sample, hence wa not analysed. The amplified peaks in most of the samples appeared equally barring completely burned out meat. However, roasted beef after ripened in soy sauce showed new peaks or deletion of a peaks with two markers. The DNA allele height and the amount of extracted DNA in roasted beef after ripening in 10% Cheongha was found to be higher than those in the raw beef. No significant correlations between DNA allele height and the amount of extracted DNA within the samples was noticed. Also, these results suggest that beef traceability using microsatellite (MS) markers is possible in various roasting beef because of bovine specific MS markers. Therefore, beef traceability system by DNA identify test would give the confidence in food safety and beef distribution system to customers.

Analysis of meat quality grade based on the DNA identity test samples were done on 320 Hanwoo (Korean cattle) raised in Gyeonggi region of Korea. 62.29% of cows and 91.35% of steers showed high quality which was above 1st beef grade. However, differences were observed between Gyeonggi Hanwoo and total slaughtered Hanwoo in Gyeonggi in the year 2009, though the sampling was entirely based high quality meat. Meat samples of pedigree registered cattle showed high rate of above 1st meat grade compared to advanced and fundamentally registered cattle. Pedigree registry is associated with quality grade of beef like the sex of cattle. Appearance rate of above 1st beef grade in offsprings of the top 9 Korean Proven Bulls produced through mating to Gyeonggi Hanwoo was 43.27% which was found to be higher than the average grade in cows (47.3%) and was 13.08% higher than the average grade in steers (77.49%). Our results showed superior genetic characters of Korean Proven Bulls which favors and influence the meat quality grade of their offsprings. Furthermore, our results claim that sex of Hanwoo irrespective of pedigreed or Korean Proven Bulls affects and/or influence the meat quality. Conclusively, the results could therefore be used as a basic data for the improvement of beef quality. However, paternity test by DNA typing and huge sample needs to be analysed to authenticate the findings.

Beef traceability, a system that provides all the records of beef production, helps customers purchase that they get to know detailed information of the Hanwoo beef. This study was carried out to investigate the DNA identity possibility in various cooking methods to ripen meat (soy sauce, gochujang sauce, 10% vinegar, 10% coke, 10% Cheongha, 10% Soju, raw, dried, and decayed) for beef traceability. The DNA content of decayed beef was higher than those of other cooking methods. It is thought that result of mixed pollutant, it did not affect amplified DNA allele height because of bovine specific microsatellite (MS) markers. The ripened sample in 10% vinegar 3 days was lowest a mount of extracted DNA (156 ng) and amplified DNA allele height (based on the raw samples to 38%) by MS markers compared with the other cooking methods. There are no significant correlation between amplified DNA allele height and the amount of extracted DNA. Therefore, beef DNA identity test in various cooking methods to ripen meat can used by bovine specific MS markers. Beef traceability system by DNA identify test will give more confidence in food safety to customers

In this study, the analysis of meat quality grade was carried out on the DNA identity test samples of 452 Hanwoo (Korean cattle) raised in Gyeongnam region in the year 2009. Appearance rate of above 1st grade from cow (70%) and steer (93.16%) showed high quality grade. On the other hand, there were the difference between this study and slaughtered Hanwoo in Gyeongnam in the year 2009 - appearance rate of above 1st grade from cow (58.77%) and steer (82.99%). It expect considered influence of the samples for beef DNA identity test that collected mainly high quality meat. Quality grade by registry classification about collected samples showed correlation between pedigree classification and quality grade that appearance rate of above 1st grade highly observed pedigree registry more than advanced registry, advanced registry than fundamental registry. Although limited to DNA identity test samples, KPN (Korean Proven Bull's Number) 452 and KPN 407 was preferred for breeding in Gyeongnam. Also average appearance rate of above 1st grade in offsprings of the top 10 Korean Proven Bulls used mating is 95.35%. It means that Korean Proven Bulls influence meat quality of offsprings positively. Thus, this analysis is expected to be a base data for the improvement of meat quality of Hanwoo raised in Gyeongnam region.

In this paper, experimental studies of the regrinding of tungsten carbide (WC-Co) tools for high-speed machining were conducted. Regrinding and a subsequent evaluation test were carried out for a flat endmill tool with diameters of 10 mm and 3 mm using a CNC five-axis tool grinder and a CNC three-axis machining center. Tool wear on the two types of endmill tools increased as the cutting length increased, and the tool wear was not influenced by the regrinding state. In case of the micro endmill with a tool diameter of 3 mm, the effective regrinding time was determined for a flank wear threshold of 0.3 mm considering the tool life according to cutting length. The tool lives of the 10 mm and 3 mm endmill tools were increased by 80% and 72%, respectively. This conclusion proves the Feasibility of the recycling of tungsten carbide materials in the high-speed machining of high-hardened materials for industrial applications.

To satisfy the demand of higher cutting performance, mechanical properties with tungsten carbide (WC-Co) tool materials were investigated. Hardness and transverse rupture strength with WC grain size, Co content and density were measured. Compared to H, K, and S manufacture maker as tungsten carbide (WC-Co) tool materials were used for high-speed machining of end-milling operation. The three tungsten carbide (WC-Co) tool materials were evaluated by cutting of STD 11 cold-worked die steel (HRC25) under high-speed cutting condition. Also, tool life was obtained from measuring flank wear by CCD wear measuring system. Tool dynamometer was used to measure cutting force. The cutting force and tool wear are discussed along with tool material characteristics. Consequently, the end-mill of K, H manufacture maker showed higher wear-resistance due to its higher hardness, while the S maker endmill tool showed better performance for high metal removal.

The purpose of this study was to examine the intention of consumer acceptance of technology in agricultural production by applying the unified theory of acceptance and use of technology (UTAUT) to smart farm. In particular, this study analyzed the intention to accept the technology of agricultural students, farmers, start-up farmers, returning farmers, and returnees in the general manufacturing industry and high-tech industries, and in agricultural sectors corresponding to primary industries. The results showed that performance expectancy, social influence, facilitating conditions, IT development level, and reliability had a significant influence on the intention to use smart farm technology. However, effort expectancy and price value were rejected because no significant impact on use intention was tested. In addition, the influences of the variables showing their influence were reliability (β=.569) > IT development level (β=.252) > social influence (β=.235) > performance expectancy (β=.182) > facilitating conditions (β=.134).

Unlike normal wheels, the Mecanum wheel enables omni-directional movement regardless of the orientation of a mobile robot. In this paper, a robust trajectory tracking control method is developed based on the dynamic model of the Mecanum wheel mobile robot in order that the mobile robot can move along the given path in the environment with disturbance. The method is designed using the impedance control to make the mobile robot to track the path, and the integral sliding mode control for robustness to disturbance. The good performance of the proposed method is verified using the MATLAB /Simulink simulation and also through the experiment on an actual Mecanum wheel mobile robot. In both the simulation and the experimentation, we make the mobile robot move along a reference trajectory while maintaining the robot's orientation at a constant angle to see the characteristics of the Mecanum wheel.

우리나라에서 폐기물을 처리하는 방법에는 크게 매립, 소각, 재활용이 있으며 일반적으로 폐기물을 수거하여 재활용 할 수 있는 부분을 제외한 나머지는 소각한 뒤 매립을 하는 방식을 택하고 있다. 매립은 계속적인 매립지 확보에 어려움을 겪고 있으며 폐기물의 배출량이 갈수록 증가됨에 따라 예상되는 매립지의 기대수명이 점점 감축되고 있다. 이러한 상황에서 우리나라에서는 폐기물을 짧은 시간 안에 매우 안정적으로 처리할 수 있는 소각기술로 시야를 넓혀야 한다. 소각은 대부분 재활용할 수 있는 폐열 및 고형화연료를 확보할 수 있을뿐더러 매립지의 수명도 효과적으로 늘릴 수 있다. 또한 소각이 완료된 후의 소각재는 수분까지도 거의 제거된 상태이기 때문에 바로 매립이 가능한 정도에 이르렀다. 환경부에서 발행한 ‘전국 폐기물 발생 및 처리 현황(2015년도 수정본)에 따르면 소각과정에서 발생된 연소재의 일일배출량은 점점 증가하는 추세이다. 따라서, 소각재를 매립하는 방법 외에 재활용할 수 있는 방안을 모색하여 매립지의 수명연장은 물론 효율적인 재활용자원으로 사용할 수 있게 만드는 것이 필요하다. 그러나 소각재는 현행 폐기물 관리법상 중금속 농도가 비교적 낮기 때문에 일반폐기물로 관리되고 있었으나 유해성 논란이 끊이질 않고 있다. 따라서, 소각재에 들어있는 유해중금속의 농도를 효과적으로 처리하여 낮추면 다른 분야에서 즉각 활용할 수 있는 좋은 재료로 사용할 수 있을 것이다. 본 연구에서는 소각재의 처리 실태를 알아보고 재활용되고 있는 방법들을 검토, 비교하고 현재 유동상식 소각로에서 배출되는 폐유동사의 재생골재로의 재활용 가능성에 대해 알아보았다. 추가적으로 유동상식 소각로에서 배출되는 보일러재와의 배합 가능성, 그리고 성분분석을 이용한 함유성분의 함량과 재활용 목표의 관계도 연구하였다. 이는 기존에 활용되고 있는 재활용 방법과 새롭게 이용할 수 있는 방법에서 원재료로 사용되고 있는 것들을 대체할 수 있는가에 대한 것이다. 기존에 사용되고 있는 원재료만큼의 효율이 나온다면 원가절감은 물론 폐기물 재활용, 나아가서는 자원재이용에 따른 환경문제 감소에 도움이 될 수 있을 것이라 판단된다.

In this study, the shake table tests were performed for seismic performance evaluation of fire protection riser pipes. The specimen was subjected to a tri-axial time history shake table test with acceleration levels corresponding to the 0.5g and 0.7g ZPA design level.

In this study, to evaluate the performance of fire resistance of the mortar with magnesium hydroxide(MH) and aluminium hydroxide(AH) which has a RCC (Radiant Control Capability) as repair material to the steel structure, temperature evaluation of mortar was conducted by increasing 500°C in the furnace. The performance of RCC can decrease a temperature to external and internal mortar. As a result, it is confirmed that temperatures of mortar with magnesium hydroxide(MH) and aluminium hydroxide(AH) were more decreased than general mortar due to the RCC effect of MH and AH. Therefore, it can be possible to apply to a repair material at the steel structure.

Damage by ship collision is related to the frequency of loads due to impact, and ships accordingly must be designed to satisfy related requirements. Another important aspect is the management of collision risks during the service period. This study performed an interim assessment of Incheon Bridge focusing on the risk of ship collision, and proposed solutions to the identified problems. It is necessary to conduct further research on collision risk management and promptly carry out interim assessments of other marine bridges.

저자들은 비파괴시험에 의한 고강도콘크리트의 강도 예측식을 제안하기 위하여 실험적 연구를 수행하였다. 본 연구에서 사용된 콘 크리트의 설계압축강도는 40~80 MPa 범위이며, 압축공시체를 제작하여 반발경도법과 초음파 속도법으로 실험한후 KS기준에 따라 압축강도 실험을 실시하였다. 실험결과는 기존의 연구자들에 의하여 제안된 다양한 실험예측식들과 비교분석하였다. 실험결과 고강도 콘크리트에서도 반발경도법과 초음파속도법의 경우 간편성과 신뢰성에 있어 콘크리트 강도를 측정하기에 충분한 유용성을 확보한 것을 확인할 수 있었다. 기 존식들과의 비교를 통하여 고강도 콘크리트에 적합한 강도예측식을 제안하였으며, 실험결과에 대한 충분한 신뢰성을 확보한 것으로 판단되 어, 향후 고강도 콘크리트 구조물에 적용할 수 있을 것으로 판단된다.