• 한국수산과학회지
• /
• 제53권4호
• /
• pp.492-498
• /
• 2020

Despite its economic importance, olive flounder Paralichthys olivaceus aquaculture industry is facing a crisis with a continuous production decline. There have been many solutions to overcome the complicate predicament proposed. Increasing genetic diversity and discovering new commercial value through selective breeding are among them. The aims of the present study are to increase the selection power of the golden flounders. We examined the genetic diversity of the breeder population of golden flounders and developed selective markers for the golden flounder population. The 6 microsatellite (MS) markers were selected from melanogenesis-related genes, which are believed to be involved in the pigmentation of fish. All markers were polymorphic (except PO4) and 5 of them had PIC value of 0.6 or above. All makers had distinctive alleles indicating either normal or golden individuals. For examples, from PO4 marker, the frequency of an allele (316) in the golden population was 100% and in normal population was 0% (P<0.001). Although some more studies with more samples at the later generations should be performed to confirm this result, the 316 allele from PO4 marker could be a distinctive tool for decision of the colors in olive flounders at an early stage of the life cycle.

• 한국동물위생학회지
• /
• 제36권3호
• /
• pp.181-186
• /
• 2013

This study was conducted to isolate the Actinobacillus pleuropneumoniae (APP) and to find out the distribution of 15 serovars mainly in southern Gyeonggi province, Korea. From July 2011 to Nov. 2012, a total of 2,204 slaughter pigs (110 herds) were inspected for evaluation of APP like pneumonic lesions. 48 (33.8%) APP strains were isolated from the 142 lungs and identified using PCR assays (cps, apx/omlA, biovar). Consequently, the serotype ratio were as in the following; type2 41.7% (n=20), type5 33.3% (n=16), type12 10.4% (n=5), type1 6.2% (n=3), type4 and 7 2.1% (n=1) and unknown 4.2% (n=2). Also serological test was implemented for 452 (83 herds) serum samples randomly collected from above slaughter pigs using commercial ELISA kits. The positive ratio of each serotype for tested pigs were 19.1% (77/404) on [2], 7.1% (32/452) on [3, 6, 8], 6.9% (28/404) on [5a, 5b], 6.2% (28/452) on [4, 7], 2.8% (9/320) on [12], 2.0% (9/452) on [1, 9, 11] and 0.0% (0/452) on [10]. And 49.3% (223/452) of pigs were positive on apxIV antibody. On the basis of latter screening test, the infected farm ratio accounted for 71.1% (59/83) and that was much higher than previously reported data.

• 한국수정란이식학회지
• /
• 제6권2호
• /
• pp.37-46
• /
• 1991

A field trial was performed to evaluate the effects of hormone treatment on estrus induction, ovulation, embryo transfer and reproductive performance in post-weaning sows. This trial involved 61 mixed breed sows of varying parity on a commercial pig farm. Sows were allocated to one of five trials: control group involved 25 sows that were treated with a single intramuscular injection of 5 ml physiological saline, 6 sows received 1,500 IU PMSG on the day of weanning and 500 IU HCG at the onset of estrus in trial I, 7 sows received 750 IU PMSG on the day of weanning and 500 IU HCG at the onset of estrus in trial II, 5 sows were treated with the same as trial II on day 28 after weanning in trial III. and 18 sows were treated with 10 mg PGF$_2$$\alpha$ plus 2 mg estradiol benzoate on day 31 after weanning in trial IV. Ovarian responses were checked by laparotomy and ova were recovered by oviducal flushing between 40 and l00hrs after mating. Fertilized ova were transferred into the oviduts of recipient sows synchroni- zed. The results obtained were summarized as follows: 1. Percentages of sows detected in standing estrus following treatment were 86~100% among trial groups. The interval from treatment to standing estrus(6l.7$\pm$0.5lhrs) in lOmg PGF$_2$$\alpha$ and 2mg estradial henzoate treated group was significantly earlier than in other trial groups(P<0.05). 2. Average number of ovulations was 11.5~37.8 among trial groups. The ovulation rate in 1,500 IU PMSG and 500 IU RCG treated group (37.8$\pm$ 19.87) was significantly different from other trial groups(P<0.05). 3. Ova were recovered by oviducal flushing between 40~ l00hrs after mating and recovery rates of ova wore 91.4% between 40~59hrs. 4. Fertilized ova were transferred into the oviducts of 8 recipient sows synchronized with 7 to 17 ova per animal. Three of the recipients were pregnant and delivered 25 piglets. 5. Four of the donor sows in those embryo collection was not successful were pregnant following oviducal flushing and delivered 23 piglets. 6. Recurrence of estrus and farrowing performance of experimental sows were observed following the experiment was no difference among trial groups, respectively.

• 한국조경학회지
• /
• 제30권3호
• /
• pp.1-11
• /
• 2002

The purpose of this study is to construct an evaluation criteria based on the relative importance and various combinations of each evaluation index and then to appraise urban biotope in terms of nature experience and recreation. After the standard of evaluation had been developed through the review of existing literature, the relative importance of the evaluation index through expert survey was determined, and the evaluation model to assess biotope value was established. The results of this study are as follows; 1) We have constructed the seventeen evaluation criteria through literature reviews, and have provided relative importance to each evaluation index of the natural in biotope, the diversity of landscape patterns, the appearance-existence of water space, the special landscape elements, and the access based on the results of expert survey. and then we have constructed an evaluation system using the relative importance criteria. 2) To evaluate urban biotope using the evaluation system constructed, we selected 14 sites. The final evaluation results of each site is as follows; The first grade areas are the water space with semi-natural style in front of Gangchon Woobang apartments, the forest zone near Page Temple at Mt. Palgong, the edge area of Jisan and Gosan and the tendril yard against Anshim middle school. The second grade areas are Hyomyung elementary school, the farm land behind the third Anshim Jugong apartment, Ehyun put and the swampy land in front of the Kangchon and Anshim construction site. The third grade areas are Seohan and Hwasung high-rise apartments at Beummul-Dong, the Korea Manpower Agency in the Sungseo industrial zone, and the adjacent area of St. Tongil. The only fourth grade area is the commercial zone near Taegu Department Store. 3) It is highly useful to evaluate urban biotope using the evaluation criteria constructed for this research, the evaluation criteria we developed may be difficult to encompass all expert opinion and the period of space-formation is difficult to estimate urban biotopes. In the future, it is necessary to gather the basic data suitable to estimate biotope and it is necessary to develop detailed evaluation criteria applicable to estimate every biotope that has specific property.

• Ocean Systems Engineering
• /
• 제7권2호
• /
• pp.143-155
• /
• 2017

For complex flexible structures such as nets, the determination of drag forces and its deformation is a challenging task. The accurate prediction of loads on cages is one of the key steps in designing fish farm facilities. The basic physics with a simple cage, can be addressed by the use of experimental studies. However, to design more complex cage system for various environmental conditions, a reliable numerical simulation tool is essential. In this work, the current load on a cage is calculated using a Morison-force model applied at instantaneous positions of equivalent-net modeling. Variations of solidity ratio ($S_n$) of the net and current speed are considered. An equivalent array of cylinders is built to represent the physical netting. Based on the systematic comparisons between the published experimental data for Raschel nets and the current numerical simulations, carried out using the commercial software OrcaFlex, a new formulation for $C_d$ values, used in the equivalent-net model, is presented. The similar approach can also be applied to other netting materials following the same procedure. In case of high solidity ratio and current speed, the hybrid model defines $C_d$ as a function of Re (Reynolds number) and $S_n$ to better represent the corresponding weak diffraction effects. Otherwise, the conventional $C_d$ values depending only on Re can be used with including shielding effects for downstream elements. This new methodology significantly improves the agreement between numerical and experimental data.

• 한국태양에너지학회 논문집
• /
• 제31권6호
• /
• pp.8-22
• /
• 2011

Investigations on modeling methods of a CFD wind resource prediction program, WindSim for a ccurate predictions of wind speeds were performed with the field measurements. Meteorological Masts having heights of 40m and 50m were installed at two different sites in complex terrain. The wind speeds and direction were monitored from sensors installed on the masts and recorded for one year. Modeling parameters of WindSim input variables for accurate predictions of wind speeds were investigated by performing cross predictions of wind speeds at the masts using the measured data. Four parameters that most affect the wind speed prediction in WindSim including the size of a topographical map, cell sizes in x and y direction, height distribution factors, and the roughness lengths were studied to find out more suitable input parameters for better wind speed predictions. The parameters were then applied to WindSim to predict the wind speed of another location in complex terrain in Korea for validation. The predicted annual wind speeds were compared with the averaged measured data for one year from meteorological masts installed for this study, and the errors were within 6.9%. The results of the proposed practical study are believed to be very useful to give guidelines to wind engineers for more accurate prediction results and time-saving in predicting wind speed of complex terrain that will be used to predict annual energy production of a virtual wind farm in complex terrain.

• 생명과학회지
• /
• 제13권6호
• /
• pp.843-848
• /
• 2003

가금티프스는 가금류에 Salmonella gallinarum이 원인균이 되어 발병하는 양계산업에 막대한 지장을 주는 질병이다. 가금티프스를 억제하기 위한 생균제 개발을 위한 목적으로써 가금티프스 원인균인 Salmonella gallinarum의 생육을 저해시킬 수 있는 길항균주를 토종닭의 내장으로부터 분리하여 생육특성과 길항물질 생산성을 조사하고, 이 균주를 분류학적으로 동정하였다. 분리된 길항균주는 Bacillus amyloliquefaciens와 98% 상동성을 나타내어 최종적으로 Bacillus amyloliquefaciens Y3로 명명하였다. 0.3% maltose, 0.2% $NH_4Cl,\; 37^{\circ}C$ pH 7에서 균생육 및 길항물질의 생산능이 가장 우수하였으나 장내 담즙에 대한 내성은 크게 나쁘지 않을 것으로 확인되어졌다. 생산된 길항물질을 추정하여 본 결과 분자량이 10,000보다 작은 저분자물질이었으며 $80^{\circ}C$에서 20분간 열처리한 후에도 80%의 활성을 유지하는 내열성 물질임을 확인할 수 있었다. 향후 선발되어진 Bacillus amyloliquefaciens Y3가 생산해내는 길항물질에 대한 연구와 개량을 통하고 장내 정착성 실험을 거쳐 우수균주로 확인되면 양계산업에 사용될 우수한 생균제로 개발이 가능할 것이라 생각된다.

• 한국수소및신에너지학회논문집
• /
• 제27권5호
• /
• pp.547-553
• /
• 2016

This paper presents the effect of a grid system on the performance of a small Savonius wind turbine installed side-by-side. Turbine performance is compared using three different grid systems; tetrahedral grid having a concentrated circular grid around turbine rotors, the tetrahedral grid having a concentrated rectangular grid around turbine rotors and the symmetric grid having a concentrated tetrahedral grid near the turbine rotor blades and a hexahedral grid. The commercial code, SC/Tetra has been used to solve the three-dimensional unsteady Reynolds-averaged Navier-Stokes analysis in the present study. The Savonius turbine rotor has a rotational diameter of 0.226m and an aspect ratio of 1.0. The distance between neighboring rotor tips keeps the same length of the rotor diameter. The variations of pressure and power coefficient are compared with respect to blade rotational angles and rotating frequencies of the turbine blade. Throughout the comparisons of three grid systems, it is noted that the symmetric grid having a concentrated tetrahedral grid near the turbine rotor blades and a hexahedral grid has a stable performance compared to the other ones.

• 한국조경학회지
• /
• 제29권1호
• /
• pp.100-112
• /
• 2001

The purpose of this study is to construct the evaluation criteria based on the relative importance and various combination of each evaluation index and then to evaluate urban biotope in terms of conservation of species and habitat. After the standard of evaluation had been developed through the literature review, the relative importance of the evaluation index through expert survey was found out, and the evaluation model of biotope value has been established. The results of this study are as follows; 1) We have constructed the nineteen evaluation criteria through literature reviews, and have provided relative importance to each evaluation index of the diversity of typical species in biotope, afforestation rate, stratification, Hemeroby grads, and the diversity of landscape patterns based on the results of expert survey. and then we have constructed the evaluation system using the relative importance criteria. 2) To evluate urban biotope using the evaluation system constructed, we selected 14 sites. The final evaluation results of each site is as follows; The III grade areas are Seohan and Hwasung high-rise apartment at Beummul-Dong, Korea Men Power /Agency in Sungs 대 industrial zone, the adjacent area of St. Tongil, and Hyomyung elementary school. The II grade areas are the farm land behind the third Anshim Jugong apartment, and Ehyun park. The I grade areas are swampy land in front of Kangchon and Anshim construction site, water space with semi-natural style in front of Gangchon Woobang apartment, forest zone near page Temple at mt. Palgong, the edge area of Jisan and Gosan, and the tendril yard against Anshim middle school. The only grade IV area is the commercial zone near Taegu Department 3) It is highly useful to evaluate urban biotope using the evaluation criteria constructed for this research, the evaluation criteria we developed may be difficult to guarantee the ability for reproduction and recovery, the appearance-number of the rare and endangered species are difficult to estimate urban biotopes. In the future, it is highly useful to evaluate biotope in terms of conservation of species and habitat through its valuation criteria developed in this research and it is necessary to develop the evaluation criteria applicable to estimation of biotope inventory and reproduction of biotope.

• 한국수정란이식학회지
• /
• 제29권4호
• /
• pp.321-325
• /
• 2014

The present study was performed on farm animals to test the effectiveness of progesterone-releasing intravaginal device (Cue-Mate$^{(R)}$ 1.56 g) and injection of prostaglandin $F_{2{\alpha}}$ ($PGF_{2{\alpha}}$) for synchronization estrus in Hanwoo cattle. The cattle were at random stage of the estrus cycle. The cows were artificially inseminated at day 7 after Cue-Mate withdrawal, using commercial semen from Korean native bulls. There was a season effect on the estrus synchronization rate. It was higher in spring (94.3%) followed by winter (93.3%), autumn (90.4%) and summer (67.2%). In summary, The results of this study revealed that season has influences on estrus behavior of cattle with no significant effect on pregnancy rate. In summary, we suggest summer reproductive management to alleviate the effects of heat stress. It should be based on intensive cooling combined with hormonal treatment. Given that different subgroups of cows benefit differently from the treatments, selective hormonal administration should be considered.