• Journal of Magnetics
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• 제18권2호
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• pp.86-89
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• 2013

This paper shows a new effective approach to measure crystallization temperature of soft magnetic underlayer (SUL) for next generation of heat assisted perpendicular recording media. This approach uses temperature dependent reflectivity, which shows a clear jump when samples are crystallized. To achieve this measurement, an optical system is set up using hot plate and infrared laser. Reflectivity of SUL $(Co_{70}Fe_{30})_{92}Ta_3Zr_5$ shows a clear jump at its amorphous-crystalline transition temperature. Experiment results show this effect is clear in infrared region, and is weak for visible light.

• Fisheries and Aquatic Sciences
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• 제8권4호
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• pp.207-212
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• 2005

Directional (sinistral) asymmetry (DA) occurs when the traits of one side of a supposedly bilaterally symmetrical organism differ in a random way from those of the other side. We examined asymmetries in gonadal growth traits within both sexes of hatchery reared ayu, Plecoglossus altivelis. The pattern of the gonadal growth from hatching to 320 days after hatching was a type of DA except for the growth in gonad weight from 140 to 180 days after hatching, although the ovary of the right side tended to exhibit more pronounced DA phenomenon.

• Journal of Magnetics
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• 제22권2호
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• pp.333-343
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• 2017

A rotating magnetic field (RMF) ${\Phi}_1-{\Phi}_2$ model was developed in consideration of the skin effect. The rotating magnetic field's induced three-dimensional flow was simulated numerically, and the influence of the skin effect was investigated. The rotating magnetic field drives the rotating convection in the azimuthal direction, and a secondary convection appears in the radial-meridional direction. The results indicate that ignoring the skin effect results in a smaller azimuthal velocity component and larger radial and axial velocity components, and that the deviation becomes more obvious with the larger dimensionless shielding parameter K.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.232-233
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• 2001

The isozymic polymorphism among the Oncorhynchus masou subspecies (O. m. masou and O. m. ishikawai) and the genetic variation in the O. mykiss species (rainbow trout and its albino mutant) were examined in present study. The biochemical marker might be identified at the sublevel of species. The aims of this study is to examine such feasibility of using the isozyme polymorphisms of the fish management and characterization between subspecies or morphomutants such as albinism. (omitted)

• 한국양식학회지
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• 제21권4호
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• pp.304-308
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• 2008

MS-222 농도별로 자연산 및 양식산 감성돔 치어의 마취효과를 비교하면 수온 $22^{\circ}C$ 고수온구가 $12^{\circ}C$의 저수온구에 비해 마취 및 회복시간이 빨랐으며, 수온 $12^{\circ}C$의 저수온에서는 자연산이 양식산에 비하여 마취 및 회복이 빨랐다. MS-222 100 ppm 농도에서 침지시간별 회복 조사에서도 $22^{\circ}C$ 실험구가 $12^{\circ}C$의 저수온 실험구에 비해 회복시간이 빨랐으며, 수온 $12^{\circ}C$의 동일 수온에서의 자연산과 양식산 치어를 비교했을 시에는 자연산 치어가 양식산 치어에 비해 마취후 회복이 빨랐다. MS-222 100 ppm에 3분간 침지후 공기중 노출시간에 따른 회복시간 조사 결과도 마찬가지로 $22^{\circ}C$ 실험구가 $12^{\circ}C$의 저수온에 비해 회복시간이 빨랐으며, 수온 $12^{\circ}C$에서는 자연산 치어가 양식산 치어에 비해 회복이 다소 빨랐다. 그러나 공기중에 노출시간이 15분 이상인 경우에 $12^{\circ}C$의 저수온 실험 구에서 수온 $22^{\circ}C$의 고수온구에 비해 회복이 빨랐다. 수온 $12^{\circ}C$에서는 자연산이 양식산 치어에 비해 회복이 빨랐다. 따라서 자연산 감성돔 치어가 양식산 치어에 비하여 마취 및 공기중 노출 내성이 강함을 알 수 있었다.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2003년도 추계학술발표대회 논문요약집
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• pp.29-29
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• 2003

In order to establish effective procedures for chromosome manipulation in Haliotis gigantea and H. discus, which are of enormous aquacultural potential, temperature-dependent measures of mitotic intervals ($\tau$$_{0}$) were determined. Mitotic intervals ($\tau$$_{0}$) in these abalone were determined by averaging the duration of the first and third embryonic divisions over a range of temperatures from 8 to 26$^{\circ}C$. The relationships of each mitotic interval at two cell ($\tau$$_{I}$), four cell ($\tau$$_{II}$ ), eight cell ($\tau$$_{III}$), sixteen cell ($\tau$$_{IV}$ ) and $\tau$$_{0}$, to temperature (T in $^{\circ}C$) in H. gigantea were log $\tau$$_{I}$ : 176.1-28.3T, log $\tau$$_{II}$ : 199.5-12.4T, log $\tau$$_{III}$ = 236.2-12.2T, log $\tau$$_{IV}$ = 269.3-14.lT and log $\tau$$_{0}$ : 83.1-32.8, respectively. The relationships of each mitotic interval at $\tau$$_{I}$, $\tau$$_{II}$ , $\tau$$_{III}$, $\tau$$_{IV}$ and $\tau$$_{0}$, to temperature in H. discus were log $\tau$$_{I}$ = 104.9-13.8T, log $\tau$$_{II}$ : 138.3-10.5T, $\tau$$_{III}$ : 172.4-10.2T, log $\tau$$_{IV}$ : 211.3-12.2T and log $\tau$$_{0}$=85.6-33.3T, respectively. There were strong, negative correlations between mitotic interval and water temperatures for all ten temperatures in these two species (H. gigantea: Y = -138.75 logX + 341.25, $R^2$ = 0.97; H. discus: Y = -112.33 logX + 255.22, $R^2$ = 0.98, where Y is mitotic interval and X is temperature).d X is temperature).rature).

• 한국어병학회지
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• 제23권1호
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• pp.85-98
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• 2010

농림수산식품부와 국립수산과학원에서는 2009년도 방류 품종 (해면 품종 22종과 내수면 품종 11품종)을 대상으로 수산동물전염병의 감염 여부를 검사하였다. 총 12개 지방자치단체에 서 방류를 실시한 것으로 나타났으며, 이 중에서 경상남도, 전라남도, 제주도 및 충청남도는 해면 품종을 주로 방류하였으며, 경기도, 전라북도 및 충청북도는 내수면 품종을 많이 방류하는 것으로 나타났다. 검사품종중에서 해산품종으로는 전복이 24.5%로 가장 많았으며, 그 다음 해삼(15.2%), 넙치 (11.5%), 감성돔과 조피볼락(6.8%), 꽃게 (5.6%), 돌돔 (5.1%), 볼락 (4.6%), 붉은쏨뱅이 (4.5%)로 나타났다. 내수면 품종 중에서는 붕어가 19.4%로 가장 많았으며, 그 다음으로 뱀장어 (17.0%), 동자개 (12.3%), 다슬기 (12.0%), 메기 (8.4)의 순으로 검사 실적이 많았다. 총 33종의 품종을 대상으로 1,080회의 검사가 의뢰되었으며, 검사항목별로 2,066건의 검사를 실시한 결과 19건에서 red sea bream iridovirus (RSIV), koi herpesvirus (KHV) 또는 white spot syndrome virus (WSSV)와 같은 병원체가 검출되어 불합격 처리되었다.

• 한국가금학회지
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• 제6권2호
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• pp.91-102
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• 1979

The basic problem of the broiler industry is that of fluctuating prices, mainly thanks to unstable supply of and inelastic demand for products as usually indicated as a peculiarity of agricultural commodities. This particularly brings the producer to a great economic risk, because he has to sell products under the condition of pure competition, whereas others from whom he has to buy deal under the condition of oligopoly or even monopoly. Therefore, producers economic position is generally placed in the worst comparing others dealing with, which results in unbalanced economic status of elements involved in broiler operation and further obstruction of industry development as a whole. A certain type of business coordination to overcome such a problem should be measured in order to improve the efficiency of entire operation and thus assure the balanced industry development. The concept of the economic integration developed in modern business system had been adapted to U.S. poultry industry which became common later around the world as a means of stabilizing producers price and whole industry as well. There are two main typos of integration; horizontal and vertical The former refers to the general grouping of similar business units, eg. a hatchery tying with other hatchery, while the latter refers to the knitting together of two or more stages of economic activities, eg. tying together among units of hatching, fled milling, production, processing and marketing. By having the industry integrated, risk and uncertainty involved in various stages of operation could be diversified. The typo of integrating contract between producers and integrators include the share of profits, flat fee payment, feed conversion payment and salary basis. In the U.S., extensive changes in production, processing, and marketing during the last few decades have changed the thicken broiler industry from one of small, widely scattered farms to one that is largo, concentrated and efficient. More than 99 percent of all broilers produced are grown under contract and by integrated firms which vary in size of operation and complexity. About 84 percent of all production is concentrated in 10 States. Some of the other factors ;hat contributed to these choses arc costs, energy use, prices, processing, marketing and demand. No integrated broiler production system has yet been applied in Korea's poultry industry, thus all stages all broiler operation run independently seeking for its own profit. Consequently, producers price fluctuate very widely around the year even more than 50 percent in a few months. This also leads to disadvantages of material supplies, processors and distributors and enforce the industry unstable. The current economic environment in Korea seems that the time for broiler integration comes and as an ideal integrator, feed millers, food processors and producers group may be considered.

• Fisheries and Aquatic Sciences
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• 제5권3호
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• pp.229-234
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• 2002

Possibility of raising sunshine bass during the winter season in Korea was investigated. Also, the effect of feed on growth and body composition of sunshine bass was compared at the various salinity. Twenty sunshine bass $(Mean\;weight\;\pm S.D.\: :\;53.9 \pm 0.24 g)$ were stocked into the eighteen circular flow-through tanks. A 2 (feed) $\times$ 3 (salinity) factorial design with triplicate was used for this study. Feed was prepared into the 2 groups: the raw fish-based me>ist pellet (MP) containing $59.5\%$ crude protein and $9.4\%$ crude lipid, and commercial sinking red sea bream feed (CF) containing $49.9\%$ crude protein and $9.4\%$ crude lipid, respectively. And salinity was prepared into the 3 groups: freshwater $(0\%)$, brackishwater $(15\%)$, and seawater $(32\%)$. Fish were fed to satiation twice daily for 6 days a week. Fish were all survived at the end of the 8-week feeding trial. Weight gain (WG) and specific growth rate (SGR) of sunshine bass were significantly (P<0.05) affected by both feed and salinity. WG and SGR of sunshine bass fed the MP were significantly (P<0.05) higher than those of fish fed the CF in the same salinity. Amount of dry feed fed was significantly (P<0.05) affected by both feed and salinity. Feed consumption by sunshine bass fed on the MP was significantly (P<0,05) higher than by fish fed on the CF in the same salinity. Feed efficiency ratio (FER) was significantly (P<0,05) affected by salinity, but not by feed. Protein efficiency ratio (PER) was significantly (P<0.05) affected by both feed and salinity. Moisture and protein content of the whole-body of fish was not significantly (P>0.05) affected by either feed or salinity. However, lipid and ash content of the whole-body of fish was significantly (P<0.05) affected by salinity, but not by feed. In conclusion, the MP was superior to CF for growth of sunshine bass during the winter season in Korea and no mortality occurred. And sunshine bass seemed to grow better in freshwater $(0\%)$ and brac-kishwater $(15\%)$ than seawater $(32\%)$ under these experimental conditions, in terms of improvement in FER and PER in freshwater or brackishwater.

• 한국패류학회지
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• 제19권1호
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• pp.19-24
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• 2003

중국에서 이식하여 어미패로 양성한 해만가리비를 수온 17.1-23.2$^{\circ}C$로 44 일간 Isochrysis galbana 등 5종의 먹이생물을 혼합시켜 공급하면서 성숙을 유도하여, 1997 년 1월 29일 및 31일 2회에 걸쳐 간출과 수온 자극을 가하여 총 4,532만개의 수정란 (평균 52 ${\mu}m$) 을 채란하였다. 난 발생 단계를 조사한 결과, D형 유생의 크기는 평균 77.5 × 63.8 ${\mu}m$이었고, 부착기 유생은 191.8 × 181.2 ${\mu}m$의 크기였으며, 부착기 유생은 이 크기에서 파판에 부착하여 치패로 발달하였다. 이 치패는 2월 14일부터 5월 7일까지 수온 22.8-26.3$^{\circ}C$, 염분 31.0-34.4에서 실내 사육한 결과, 평균 각장 3.04 mm로 성장하였다. 비단가리비의 경우는, 부착기의 부착유생들은 채묘기(collector) 에서 떨어지면 폐사하게 되는데, 이것은 Argopecten balloti에서 나타나는 바와 같이, 족사에 의한 부착기간이 짧아서가 아니라 부착유생들이 각기 소수의 족사를 가지기 때문에 채묘기에 대한 부착력이 약하여 부착유생의 생존율이 비교적 낮았던 것으로 사료된다.