검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 897

        241.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to determine the growth performance and carcass characteristics of fattening Hanwoo heifers slaughtered at different ages. Twenty one Hanwoo heifers were randomly allocated to three groups (32, 36 and 40 months age), with 7 steers each, respectively. In the result, initial and final body weights were 125.6 and 651.0 kg, respectively. Average daily gain was significantly low at final stage compared with other growth stages (p<0.05). Dry matter intake was the peak at the intermediate fattening stage (p<0.05). The feed conversion ratio was significantly lower at growing stage compared to other stages (p<0.05). In yield traits, carcass weight was greater in 40 months age group compared to other groups (p<0.05). Yield index was greater in 32 months group compared to 40 months of age (p<0.05). Marbling score, meat color, fat color, texture, and maturity were not different among groups (p>0.05). However, marbling score tended to be increased in 40 months age group (5.9) compared to other groups. The appearance rate (%) of meat quality grade more than 1+ was greater at 40 months old group than other groups.
        4,000원
        242.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The study was conducted to investigate the comparison of pregnancy rate and transferable embryos produced by genetically superior Korean cows (Hanwoo) of livestock farms. Eighteen Hanwoo donors were superovulated with gonadotropin for 4 days combined with Progesterone Releasing Intravaginal. Embryos were recovered 7 days after the second insemination by flushing the uterus with embryo collection medium. No differences were observed in the efficiency of rate of superovulation in groups A (low nutrition) and B (highnutrition) it was observed to be 100.0% and 87.5%, respectively. The mean numbers of total embryos were 10.8±3.4 and 8.9±2.5, and transferable embryos were 7.5±3.3 and 4.0±1.5 in groups A and B, respectively. The pregnancy rates after embryo transfer were 23.5%, 20.0%, C 80.0% and 55.6% in farm A, B, C, and D, respectively. In conclusion, results suggest that superovulation could be used quite effectively to raise superior Hanwooembryos. However, physical and biological condition of recipients greatly affects the rate of pregnancy.
        4,000원
        243.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES: This study aims to suggest a proper left-turn treatment method for the bicycle traffic flow at four-legged intersections. METHODS: Four types of crossing methods are proposed and analyzed : (1) indirect left turn, (2) direct left turn, (3) direct left turn on a Bike Box, and (4) direct left turn on bike left turn lane. The VISSIM simulation tests were conducted based on forty-eight operation scenarios prepared by varying vehicle and bicycle traffic volumes. RESULTS : The results from the four-legged signalized intersections suggest that (1) the indirect left turn is appropriate when vehicle demand is high, (2) the direct left turn is efficient on most traffic situation but the safety is a concern, (3) the direct left turn on a Bike Box is appropriate when bicycle demand is high while vehicle demand is not, and (4) the direct left turn on a bike left turn lane is appropriate when both vehicle and bicycle demand are low. CONCLUSIONS : The direct left turn of bicycle provides more efficiency than the indirect left turn at the four-legged intersections but to apply the methods and to study more, advanced evaluation methods, related law, and insurance programs are needed.
        4,500원
        246.
        2013.03 구독 인증기관 무료, 개인회원 유료
        The objective of this study was to investigate the effects of abnormal ovarian cycles after superovulation treatment of Holstein Donor Cows. CIDRs were inserted into the vaginas of twenty two head of Holstein cows, regardless of estrous cycle. Superovulation was induced using folliclar stimulating hormone (FSH). For artificial insemination, donor cows were injected with PGF2α and estrus was checked about 48 hours after the injection. Then they were treated with 4 straws of semen 3 times, with 12-hour intervals. Embryos were collected by a non-surgical method 7 days after the first artificial insemination. The cows were considered to have resumed ovarian cyclicity on the day of ovulation if followed by regular ovarian cycles. Seventy two point seven percentage of the cows(16/22) had normal resumption of ovarian cyclicity(resumption within 40 days after superovulation), and 27.3%(6/22) had delayed resumption(resumption did not occur until>40 days after superovulation). Delayed resumption Type Ⅱ(first ovulation did not occur until ≥40 days after superovulation, i.e. delayed first ovulation 13.6%) were the most common types of delayed resumptions. The mean numbers of total ova from < 10 and 10≤ of corpora lutea(CL) was 7.8±1.8 and 12.7±2.7, respectively. The number of transferable embryos differed between < 10 and 10≤ CL was 5.4±1.3 and 8.1±3.4, respectively. Four point five percentage of the cows(1/22) did not resumption their ovarian cyclicity until 60 days after superovulation treatment. Diverse researches on the superovulation treatment method that is suitable for high-producing Holstein donor cows would contribute to preventing ovarian cyclicity disorder, as well as to the early multiplication of cows with superior genes by increasing the utilization value of donor cows.
        4,000원
        247.
        2013.03 구독 인증기관 무료, 개인회원 유료
        The objective of this work was to analyze the concentrations of progesterone (P4) and estrogen (E2) hormones changed during estrus synchronization in dairy heifers. Estrus synchronization was carried out with CIDRⓇ (Controlled Intravaginal Drug Release) devices. Corpus luteum (CL) was classified into three grades based on its size and palpable characteristics. The concentrations of P4 and E2 were measured by enzyme-amplified chemiluminescence. Serum P4 concentration was markedly low at the estrus stage (36 hrs after removal of CIDR) compared to other stages, while E2 concentration was kept high during estrus stage. The serum P4 concentration was highest in the CL classified into gradeⅠ. These results indicate that P4 concentration could be used as a criteria for determining recipients for artificial insemination or embryo transfer in dairy cattle.
        4,000원
        248.
        2013.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study is the research appling the representative Displacement-Based Design which is the basic concept of Direct Displacement Based Design proposed by Chopra and Goel to original Reinforced Concrete moment frame and determining the thickness of retrofit Steel Jacket about the Maximum design ground acceleration, and developing the more improved Algorithm as well as program by the Retrofit Design method and Nonlinear analysis by the Performance design method before and after reinforcement appling the determined retrofit thickness. It also shows the result of the seismic performance improvement which is the ratio of seismic performance appreciation result yield displacement 19%, yield strength ratio 24%, displace ductility ratio the maximum 27% comparing Multi degree of freedom, column member of Reinforced Concrete with the performance improvement column member considering the thickness of the determined Steel Jacket. The developed Algorithm and program are easy to apply seismic design and application to the original Reinforced Concrete building, at the same time, it applicate to display well the design result of Target displacement performance level about nonlinear behavior.
        4,000원
        249.
        2012.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        이 연구의 목적은 토마토 재배시설을 종합적으로 평가할 수 있는 지표를 개발하는데 있다. 이를 달성하기 위해 관련 문헌 및 선행 연구들을 분석하여 예비 평가항목을 추출하고, 전문가 집단을 대상으로 델파이 설문조사를 실시하여 평가 항목, 등급 및 기준으로 구성된 평가지표를 개발하였다. 토마토 재배 및 시설 관련 교수, 연구원, 농업인(현장 사용자) 등으로 구분하여 100명의 전문가 패널을 선정하였으며, 1차부터 3차까지 폐쇄형 질문 방식의 설문조사를 진행하였다. 그 결과 최종적으로 확정된 평가 항목은 4개 대분류 영역과 39개 세부 평가항목으로 이루어졌다. 대분류 영역은 시설 구조적 요소, 시설 설비적 요소, 재배적 요소, 생산 기반적 요소이며, 요소별로 각각 9개, 15개, 7개, 8개씩 세부 평가항목으로 구성되었다. 또한 전문가 의견을 수렴하여 39개 평가항목별로 가중치를 산정하고, 등급 및 기준을 설정하였다. 이 연구에서 개발된 평가지표는 새로운 시설 모델 개발, 사용 중인 시설에서 우선적으로 보완해야 될 사항을 판단하거나 정부 지원사업의 효율성을 높이는데 중요한 역할을 할 것이다.
        4,300원
        250.
        2012.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        부재 교차 결합부 조건에 따른 초기강성은 고정 조건인 경우와 비교하여 반고정 조건인 경우 33% 작게 나타났으나 부재 교차 결합부 특성에 의하여 재하지점과 3m 떨어진 지점에서는 9% 크게 나타났다. 즉, 고정 조건인 경우 구조물 전체로 하중이 분산되어 재하지점과 떨어진 지점에서는 상대적으로 반고정 조건 구조물의 강성이 높게 나타났다. 기초 조건에 따른 초기 강성은 강관 삽입 기초의 경우에는 고정기초 조건과 비교하여 31% 크게 나타났으며, 휨강성은 20% 높게 나타났다. 인터페이스 요소(beam interface element, BIE) 및 지반요소(3-D solid element)를 사용하여 재하시험 결과를 기반으로 각종 계수를 산정하고 시험조건과 동일하게 수치모델링하여 유한요소해석을 수행한 결과 실험결과와 유사한 구조거동을 나타냈다. 그러나 극한하중 조건에서는 비선형 특성의 발현 등에 의하여 다소 상이한 결과 값을 보였다. 이상의 결과로부터 플라스틱 필름 온실의 설계 및 구조성능 평가에서 절점 및 지점 조건에 대한 임의 또는 과다한 이상화는 구조물의 성능 평가에 적지 않은 영향을 줄 수 있음을 알 수 있었다. 한편 플라스틱 필름 온실은 세장한 부재로 구성된 유연한 철골 구조물이므로 구조성능 산정에 있어서 좌굴과 함께 대변형 및 지반의 비선형 특성 등을 충분히 고려해야 할 것으로 판단된다.
        4,000원
        251.
        2012.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 흑염소 비육에 있어서 조사료원이 볏짚 단용인 경우 농후사료 급여수준이 흑염소의 사료섭취량, 체중변화, 도체특성 및 경제성에 미치는 영향을 구명하기 위하여 실시하였다. 비육 흑염소 40두를 공시하여 농후사료 급여수준을 체중의 1.5% (T1), 2.0% (T2, 농가관행), 2.5% (T3) 및 자유채식구(T4)로 나누어 급여 하였고 조사료는 볏짚을 자유채식 시켰으며그 결과는 다음과 같다. 볏짚인 조사료 섭취량은 농후사료 급여수준이 증가 할수록 감소하였으며, 흑염소의 일당증체량은 체중대비 농후사료 급여수준 1.5, 2.0, 2.5% 및 자유채식구가각각 22, 50, 69 및 94 g으로 농후사료 급여수준이 증가할수록 유의적으로 증가하였다(p <0.05). 비육 흑염소의 도체율은 농후사료 급여수준을 체중비 1.5, 2.0, 2.5% 및 자유채식 시켰을 때 각각 41.77, 42.78, 46.12 및 49.78%로농후사료 급여 수준이 증가할수록 증가하였으며(p<0.05), 지방률도 농후사료 급여수준이 증가 할수록 유의적으로 증가하였다. 경제성 분석에서는 농후사료 급여수준이 증가할수록 소득은 증가하였으며, 자유채식구가 두당 34,270원으로 가장 소득이 높았다. 이상의 결과를 종합적으로 고려할 때 조사료 자원이 볏짚 단용일 경우 비육 흑염소의 농후사료 급여 수준은자유채식 시키는 것이 사료이용성, 발육, 도체율 및 경제성에서 가장 유리할 것으로 사료되며, 흑염소의 비육을 위한 조사료 자원으로서볏짚 단용은 농후사료비의 가중을 가져오므로앞으로는 흑염소 비육을 위한 새로운 조사료자원의 개발이 필요하다고 하겠다.
        4,000원
        252.
        2012.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 토마토 재배에 적합한 규격을 가지면서 기상재해에 안전한 토마토 재배용 연동 비닐하우스를 설계하였다. 토마토 하우스의 규격은 폭 7m, 측고 4.5m, 동고 6.5m이다. 1995년에 농촌진흥청에서 개발한 1-2W형 하우스와 비교해서 폭은 같지만 측고는 1.8m, 동고는 2m 더 높다. 중방은 작물하중과 장치하중을 견딜 수 있도록 트러스 구조로 설계하였다. 토마토 하우스는 높으면서도 내재해 설계 기준(MIFFAF, 2010)에 맞게 만들어졌다. 즉, 최고 설계 기준인 풍속 40m·s-1, 적설 40cm 이상에 안전하도록 구조안전성 분석을 통해 하우스 기둥, 서까래 등의 부재 규격과 설치 간격을 설정하였다. 1-2W형 하우스와 달리 토마토 하우스에는 랙-피니언 타입의 천창을 용마루 부분에 설치하여 외부 공기 유입과 자연 환기를 극대화할 수 있도록 하였다. 하우스 높이가 증가하면 난방비는 증가하므로 토마토 하우스에는 보온력이 우수한 다겹 보온커튼을 설치하여 하우스 바깥으로 빠져나가는 열을 최소화하였다.
        4,000원
        253.
        2012.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Preservation, distribution and share of regional genetic resources are one of the hot topics of international debates. Korean government under National Institute of Animal Science (NIAS) supervision made a law that initiated national management system of livestock genetic resources in agriculture and fishery (July, 2012). NIAS preserve domestic livestock genetic sources of Chikso (Korean brindle cattle), Heugu (Korea black cattle), native pig and native chicken under the strategies of multiple place guardians to keep these minor animals from getting extinct through various reasons. A total of around 3,300 animals are under protection currently. Around 70,000 germ cells of Chikso, Heugu, native goat, etc, are stored by cryopreservation method. Moreover,around 30,000 samples of whole blood and DNA are stored in deep freezers. NIAS also constructed Animal Genetic Resource Information Management System (AGRIMS) and stored information including the phenotypes and genotypes of livestock genetic resources. We also have built companionships with nine provincial livestock institutes and two universities regarding rare livestock animal management since 2008. These companion organizations have around 16,000 animals of 11 breeds in their custody. Internationally, we keep on registering these breeds on FAO and Domestic Animal Diversity Information System (DAD-IS) database systems. Recently we updated registration of 24 breeds of six species such as Chikso, Chookjin Chamdon, Ginkkoridak, Jindo, etc.
        4,000원
        254.
        2012.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The objective of this study was to investigate the influence of parity on chemical composition and meat quality of Hanwoo cows (n=74, 2-15 years old). The beef loin and top round muscle samples were obtained and divided by 3 groups of parity numbers (G1, 0; G2, 1-3; G3, 4-9 times). Loin and top round from G1 had significantly higher intramuscular fat contents and lower protein contents than those from G3 (p<0.05). There was no significant difference in collagen contents among 3 parity groups (p>0.05). In meat color, G1 was higher in a* values for loin and higher in L* and a* values for top round muscle (p<0.05). The loin from G1 had significantly lower cooking loss (%) than G3, however, there was no significant difference in water holding capacity among 3 parity groups. For top round muscle, G3 had significantly higher Warner-Bratzler shear force values and lower water holding capacity values than G1 (p<0.05). In fatty acid composition, G1 had significantly higher C18:1n7 and C18:1n9 contents for loin, and it had significantly higher C16:1n7 and C18:1n7 contents for top round than those of the other groups (p<0.05). In free amino acid composition, alanine was highest and followed by glutamine, phenylalanine, isoleucine, proline, glycine, methionine. In conclusion, the parity conditions influenced on chemical composition and meat quality depending on different cut of Hanwoo cows, and the parity numbers were related with the age of cows.
        4,000원
        255.
        2012.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : This paper aims to improve the evaluation method of the Level of Service(LOS) for urban streets presented by the current Korean Highway Capacity Manual(KHCM) and suggest its utilization plan as a part of the methods to evaluate the sustainability of a transportation policy. METHODS : This paper carried out a research in 3 steps to develop a new evaluation method. First of all, this paper reviewed the previous studies related to the LOS of urban streets and the socially requested items for a sustainable transportation system. Then this paper derived an index and weight through expert questions to select an evaluation index. Lastly, this paper compared the results according to the existing evaluation methods with the new evaluation methods through case studies. This paper used an Analytic Hierarchy Process(AHP) for importance analysis and weight selection between new evaluation items and indices, and applied a Grey System Theory(GST) for a synthetic and integrated evaluation between the selected evaluation indices. RESULTS : As a result of evaluating the LOS according to the existing evaluation methods and the integrated evaluation methods using a GST through case studies, it was analyzed that new methods' results are less than or equal to the existing evaluation methods; and as a result of applying a weight between evaluation indices according to AHP, it was noticed that the total score seems to rise more when the LOS in the existing evaluation is calculated lower. It was analyzed that the LOS calculated by reflecting the newly established evaluation items and the importance between indices in this study has difference from the LOS of the existing urban streets. CONCLUSIONS : It is expected that this evaluation method can diagnose the current conditions when establishing a future sustainable traffic system and can be used for the measurement of the sustainability effects of the improvement plans and so on.
        4,000원