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        검색결과 102

        23.
        2018.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In South Korea, Jeju Island has a role as a test bed for electric vehicles (EVs). All conventional cars on the island are supposed to be replaced with EVs by 2030. Accordingly, how to effectively set up EV charging stations (EVCSs) that can charge EVs is an urgent research issue. In this paper, we present a case study on planning the locations of EVCS for Jeju Island, South Korea. The objective is to determine where EVCSs to be installed so as to balance the load of EVCSs while satisfying demands. For a public service with EVCSs by some government or non-profit organization, load balancing between EVCS locations may be one of major measures to evaluate or publicize the associated service network. Nevertheless, this measure has not been receiving much attention in the related literature. Thus, we consider the measure as a constraint and an objective in a mixed integer programming model. The model also considers the maximum allowed distance that drivers would detour to recharge their EV instead of using the shortest path to their destination. To solve the problem effectively, we develop a heuristic algorithm. With the proposed heuristic algorithm, a variety of numerical analysis is conducted to identify effects of the maximum allowed detour distance and the tightness of budget for installing EVCSs. From the analysis, we discuss the effects and draw practical implications.
        4,500원
        25.
        2018.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        작물의 생산량은 광합성과 밀접한 관계가 있으며, 광합성 속도는 다양한 환경 요인에 의해 변화한다. 광합성 속도는 작물의 생육 상태나 생육 속도를 판단하는 지표로 사용되며, 작물 재배 시설을 구축하는 데 고 려해야 하는 중요한 요인이다. 이 연구의 목적은 광도, CO2 농도 및 생육 단계에 의해 변화하는 로메인 상추 의 군락 광합성 속도 모델을 개발하는 것이다. 군락 광합성 속도는 정식 후 5, 10, 15, 20 일차에서 5단계의 CO2 농도(600-2,200μmol·mol-1)와 5단계의 광조건(60-340μmol·m-2·s-1)이 처리된 3개의 밀폐 아크릴 챔버(1.0 × 0.8 × 0.5m) 내에서 측정하였다. 먼저 세 가지 환경 요인을 사용하는 식들을 곱하여 만든 단순곱모델을 구성 하였다. 이와 동시에 생육 시기에 따라 변화하는 광화학 이용효율과 카르복실화 컨덕턴스, 호흡에 의한 이산화탄소 발생 속도를 포함하는 수정 직각쌍곡선 모델을 구성하여 단순곱 모델과 비교하였다. 검증 결과, 단순곱 모델의 R2는 0.923이었으며, 수정 직각쌍곡선 모델의 R2는 0.941을 나타내었다. 따라서 수정 직각쌍곡선 모델 이 광도, CO2 농도, 생육 단계의 3 변수에 따른 군락 광합성 속도를 표현하는 데 더욱 적합한 것으로 판단하 였다. 본 연구에서 개발된 군락 광합성 모델은 식물공장에서 상추 재배를 위해 생육 단계별로 설정해야 할 최 적의 광도와 CO2 농도를 결정하는데 도움이 될 것으로 생각된다.
        4,000원
        27.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A 2-year-old female Maltese dog was presented with a history of anemia and vaginal hemorrhagic discharge. Physical examination revealed severe vaginal hemorrhagic discharge, abdominal pain, pale mucous membranes, low blood pressure and dehydration. Results of serum biochemistry, hematology, venous blood gas, and electrolyte canine C-reactive protein (CRP) test revealed severe normocytic normochromic anemia, severe neutropenia, a high level of CRP, hypoglycemia, and imbalanced electrolytes. Abdominal ultrasound examination showed focal hypoechoic defect with loss of layering in uterine horn wall. A laparotomy revealed a clear reddish fluid in the abdomen, the fistula of left and right uterine horn, the purulent discharge from fistula, and symptoms of septic peritonitis near by the fistula site. The bitch underwent ovariohysterectomy and recovered without complication. Histopathological diagnosis of the uterine fistula site was adenocarcinoma.
        4,000원
        28.
        2016.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to investigate the effects of various mulching materials on growth and yield of okra (Abelmoschus esculentus L. Moench). Three kinds of polyethylene (PE) mulching materials were used which are: black (Black), green (Green), and white and black on both sides (White), black non-woven fabric (Fabric), and barley straw (Straw) and the control plot (Control) were also used in this study. The change of soil temperature was observed in various mulching materials with Green showing the highest average temperature of 24.4o, followed by Black > Fabric > Control > White > Straw. The variation of plant length,, aboveground weight, and root weight were constant in the order of Green > Black > White > Fabric > Control > Straw. Total yield (number of fruits) were 281,000 in Green which was the highest yield, and the least was from Straw which was 62.3% of Green. Total weight of fruits in Green was 395 kg which was the heaviest, and in Straw was least with 226 kg Hence, the weight of fruits
        4,000원
        29.
        2015.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The objective of this study was to evaluate the initial detection time and development of the fetal genital structures using ultrasound in twelve pregnant small bitches. The initial detection time of the fetal genital structures was as follows: genital tubercle at days 32.6; os penis at days 45.2; labia at days 45.7; scrotum at days 47.5. Ultrasonograms of fetal genital structure according to gestational stage were as follows: Undifferentiated stage (before day 35), the genital tubercle was observed to have a small elevation and just a hyper-echogenic structure in the midline between the umbilical cord and the tail in male and female fetus. Migration stage (between day 35∼45), the genital tubercle was observed as a hyper-echogenic, bilobular, oval shaped and the genital tubercle began to migrate from the initial position toward the umbilical cord in males, and toward the tail in females. Differentiated stage (after day 46), the penis and os penis were observed to stand out in the abdominal wall and the scrotum was observed toward the perineal region in male fetuses. The labia was detected at the base of the tail in female fetuses. These results indicate that ultrasound of fetal genital structures could be useful for fetal gender determination and a completely prepartum evaluation of the canine fetus.
        4,000원
        30.
        2015.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A 10-year-old spayed female Yorkshire Terrier visited for a physical checkup. The bitch had a history of ovariohysterectomy for treatment of pyometra a year ago. On physical examination, the dog was bright and alert. Complete blood counts, serum biochemistry and blood gas analysis results did not show any deviations within normal ranges. Radiographic and ultrasonographic examinations revealed unilateral hydronephrosis and hydroureter of the right kidney and ureter, and obstruction of the distal ureter was observed. On the basis of these results, nephroureterectomy was performed. During the operation, the adhesion of the distal ureter and surrounding tissue cells were observed without the evidence of the ureteral ligation. The distal ureteral obstruction was presumed to be adhesion caused by fibrous tissue formation between ureter and retained broad ligament, or incompletely removed blood clots following ovariohysterectomy. This case report describes the occurrence of hydroureteronephrosis caused by adhesion of the distal ureter following ovariohysterectomy in a bitch.
        3,000원
        31.
        2015.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aimed to analyze characteristics of the seasonal habitat use of reintroduced Long-tailed Gorals (n=7) in Woraksan (mountain) National Park. We collected 10,721 goral coordinates in Woraksan (mountain) National Park via transmitters, and analyzed habitat use (e.g., aspect, distance from stream and road) from November 2006 to January 2013. Aspect use was southwest (22.6 %), and seasonal aspect use had a southwestern slope (in the spring, summer, and autumn). A northwestern aspect was detected in winter, but slope of 30°∼35° (19.0 %) was used regardless of the season and mean elevation use was 500 m. Moreover, seasonal use was higher in the summer and lower in the winter and spring. The distance from the stream was mainly 50 m in 17.2 %, except in the winter (distance of 300 m), and it was within 50 m in the spring, summer, and autumn. The distance from the road was 100 m in 25.7 %, and seasonal use was within 100 m except for the winter. Thus, we examined significant differences in the habitat use of reintroduced gorals in Woraksan (mountain), and provide elementary data for habitat stabilization of Woraksan (mountain) National Park where goral restoration has advanced.
        4,000원
        32.
        2015.02 구독 인증기관 무료, 개인회원 유료
        Preservation of liquid semen is an important factor for breeding management in swine industry. Oxidative stress of spermatozoa during liquid preservation has a detrimental effect on sperm quality and decreases fertility. Objective of this study was to determine the effect of antioxidant, Quercetin, on capability of porcine liquid semen preservation. Freshly collected porcine semen from boars (n=3), having proven fertility was counted, diluted to 3×107/mL and divided into 5 different semen extenders. Aliquots of diluted semen with different extenders were subjected to measure the pH, motility, viability and sperm DNA structure status on elapse time after preservation for 10 days. For the first 3 days, semen preserved in all 5 different extenders maintained their initial pH and either gradually decreased or increased thereafter, indicating lipid peroxidation has started. Sperm motility (r=0.52, p=0.01) and viability (r=0.55, p=0.03) had positive correlation with semen pH. Sperm motility was maintained well (p<0.05) in especially 2 extenders containing Tris and antioxidant compared to other extenders, suggesting both Tris and antioxidant worked as pH regulator and had beneficial effects on sperm characteristic during preservation. Sperm DNA structure status accessed by sperm chromatin structure assay on elapsed time after preservation, tended to be higher in semen preserved without antioxidant. Taken together, addition of antioxidant to extender prevents the sperm from oxidative stress during storage in mechanism by which antioxidant slows the lipid peroxidation, and thus reduced the reactive oxygen species in preserved porcine semen resulted in maintaining semen pH, sperm motility and viability for 7~10 days.
        4,000원
        33.
        2015.01 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Hot rolling of Mg-6Zn-0.6Zr-0.4Ag-0.2Ca-(0, 8 wt%)Li powder was conducted at the temperature of 300 oC by putting the powder into the Cu pipe. The microstructure and mechanical properties of the samples were observed. Mg-6Zn- 0.6Zr-0.4Ag-0.2Ca without Li element was consisted of α phase and precipitates. The microstructure of the 8 wt%Li containing alloy consisted of two phases (α-Mg phase and β-Li phase). In addition, Mg2Zn3Li was formed in 8%Li added Mg-6Zn-0.6Zr- 0.4Ag-0.2Ca alloy. By addition of the Li element, the non-basal planes were expanded to the rolling direction, which was different from the based Mg alloy without Li. The tensile strength was gradually decreased from 357.1 MPa to 264 MPa with increasing Li addition from 0% to 8%Li. However, the elongation of the alloys was remarkably increased from 10 % to 21% by addition of the Li element to 8%. It is clearly considered that the non-basal texture and β phase contribute to the increase of elongation and formability.
        4,000원
        34.
        2014.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A 6-year old, Greyhound bitch was presented with vaginal hemorrhage and dystocia. Physical examination revealed severe vaginal hemorrhage, abdominal pain, pale mucous membranes and the presence of solid structures to abdominal palpation. A hematological test revealed a marked hemorrhagic anemia, and abdominal radiography and ultrasonographic examination showed two dead fetuses in the uterus. Median laparotomy revealed a rupture of the left uterine horn adjacent to the bifurcation, region of weakened uterine wall in the right uterine horn, blood clots and uterine fluids in abdominal cavity without septic peritonitis. The bitch underwent ovariohysterectomy and recovered without complication.
        3,000원
        35.
        2014.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was performed to establish a new parameter for estimating gestational age and predicting parturition day by ultrasonographic measurement of deep portion of telencephalic vesicle (DPTV) diameter in small dogs. Fetal head diameter (HD) and DPTV diameter were measured in 15 pregnant Pekingese bitches, from Day 15 to the parturition day, and evaluated the correlation between gestational age. HD was measured from day 29 of pregnancy to parturition day and increased from 4.9 ± 2 mm to 25.5 ± 0.7 mm. Especially, from day 38 of pregnancy to parturition day, HD uniformly increased about 0.6 mm per day and was significantly and linearly relative to gestational age during this period (r2>0.99). DPTV diameter was measured from day 35 to day 60 of pregnancy and increased from 3.2 ± 0.9 mm to 11.5 ± 0.7 mm. Especially from day 38 to day 60 of pregnancy, DPTV diameter uniformly increased about 1 mm per 3 days and was significantly and linearly relative to gestational age during this period (r2>0.99). In conclusion, DPTV diameter could to be a useful parameter for the estimation of gestational age and the prediction of parturition day when used alone or in combination with HD during the second half of pregnancy.
        4,000원
        37.
        2014.04 구독 인증기관·개인회원 무료
        Luehdorfia puziloi (Erschoff, 1872) is a monophagous butterfly species that occurs only once during spring in a year and distributed nationwide in Korea. From 2012 to 2013 the adult emergence has been monitored to assess how the species responds to temperature rise in the country. Monitoring sites were located in four different provinces, two in the northern part of the country and the others the southern part. In each site a small emergence cage was set up with 60 to 70 pupae and a HOBO data logger to record the soil temperature of the site from February to April. The earliest record from literatures and specimen collection data was 28th of March in Geojae-gun, one of far south parts of the country, during the late 90’s. In 2013, the butterfly started emerging in a southern site, Namhae-gun, from 20th of March, and it was the earliest record so far. The emergence from all of the sites occurred on average 7.75 days faster in 2013 than 2012. The emergence patters during the two years clearly showed that the adult emergence reached to 50% emergence rate faster as the soil temperature rose.
        38.
        2013.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Cell-free fetal RNA has been highlighted as useful tools for the fetal sex determination or other genetic inherent disorder. However, there is no knowledge about the sex determination using cell free fetal RNA in bovine field. Thus, the present study aimed to evaluate the presence of transcripts of DDX3Y, USP9Y and ZRSR2Y genes in maternal plasma of pregnant cows to determine the sex of the fetus using real-time quantitative polymerase chain reaction assay, and verify its accuracy, sensitivity and specificity compared with the molecular testing and the calf sex at birth. Transcripts of USP9Y and DDX3Y genes were expressed in the all plasma of males and females both the control group and the experimental group. However, ZRSR2Y gene was matched up with the molecular testing and the true sex in control group and has an overall accuracy of 82.6%, a sensitivity of 75%, and a specificity of 100% in experimental group. Therefore, these results indicated that real time PCR technique, as a noninvasive and cost-efficient method, is possible to determination fetal sex in the bovine species using circulating cell free RNA in maternal plasma and especially ZRSR2Y gene could be a good candidate for the RNA based sex determination work.
        4,000원
        39.
        2013.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A 11-year, 9-month-old female Shih-tzu was referred for evaluation of the body conditions. According to the physical examination and ultrasonography, the left ovarian mass was detected. For the removal of ovarian mass, an ovariohysterectomy was performed. Grossly, the ovarian mass was full of hairmatrix on the cut surface of the mass. Histopathological findings revealed a characteristic of teratoma, such as laminated keratines, hair, sebaceous glands, neuron tissue, differentiated bone and cartilage. The ovarian mass was well-differentiated components of 2 germ layers, and diagnosed as a mature teratoma.
        3,000원
        40.
        2013.12 구독 인증기관 무료, 개인회원 유료
        Pig producers have been shown keen interest of the number of spermatozoa in a semen dose since pig artificial insemination introduce. However, determining the minimal number of spermatozoa need per AI without detrimental effect on overall reproductive performances is not an easy question to answer. To increase the efficiency of semen utilization in pig AI, optimum number of spermatozoa per dose needed to determine. The objective of this study was to determine the reproductive performance and factors that affect on-farm application of low-dose semen insemination in sows. Data were collected from Darby Genetics AI studs from 4th of June to 7th of July, 2012 (n=401). The numbers of parturition were 84, 234 and 83 in sows inseminated with doses of 1.5×109, 2.0×109 and 2.5×109 spermatozoa in 100ml extender, respectively. There were no significant differences on reproductive performances such as gestation pe-riod, total born, total born alive, stillbirth and mummy in sows inseminated with different semen doses. The average number of born alive was 10.5, 11.0 and 10.4 from sows inseminated with 1.5×109, 2.0×109 and 2.5×109 sperms, re- spectively. Also, number of spermatozoa per dose did not affect litter size (p>0.10). There were no significant differ-ences of maternal genetic line difference on gestation period, total number born, number born alive, born dead and mummy. The estimated correlation coefficients of the different semen doses with total number born, number born alive, born dead and mummy were r=—0.00, —0.01, 0.02 and 0.02, respectively. Taken together, the result of this study suggested that when semen was appropriately inseminated after induced ovulation, insemination with low-dose (1.5∼2.0×109) semen dose not adversely affect sow’s fertility.
        4,000원
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