• 동력기계공학회지
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• 제8권1호
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• pp.30-35
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• 2004

This paper represents the numerical analysis on effect of the environmental velocity for circular heating source with heat generation. In general heating system, the oil and sheath heater is widely used, but these systems have many problems. So, the heating source with carbon ingredient has been researched in many country about manufacture, thermal and electrical properties. In this research, a circular heating source was studied through numerical analysis on several conditions of unsteady state, beat generation and environmental velocity. The temperature distributions at steady state is appeared as a non-linear pattern with variations of environmental velocity. So, the correlation equation between temperature at steady state and environmental velocity was obtained.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 1995년도 VTS and IBS 95 The Korean Institute of Navigation 1995년도
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• pp.73-88
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• 1995

I. Introduction II. State of vessel-source marine pollution 1. Pollution by tanker accidents 2. Pollution by tanker operations 3. Pollution by chemicals 4. Pollution by garbage and sewage III. Regulatory regime for ship safety and vessel-source 1. Regime for ship safety 2. Regime for vessel-source marine pollution prevention IV. Cause analysis of Contemporary vessel-source marine pollution. 1. Diversity of interested parties of shipping 2. Fierce international competition of shipping 3. Wide variagions in ship safety indicators by natons 4. Limitation of enforcing oil spill activities 5. Limitation of international countermeasures V. Summary conclusions and suggestions Note and References

• 한국대기환경학회지
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• 제2권2호
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• pp.9-18
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• 1986

For identification and apportionment of sources emitting particulate matters in environment, the multi-elemental characterization of size-density fractionated particulate matters was carried out. Eight types of samples were tested; soil, flyash released from burning of bunker-Coil, diesel oil, coal, and soft coal, urban road-way dust, urban dust fall, and airborne particulate matter. The fractions of particulate matters obtained by heavy liquid separation methos with a series of dichloromethane-bromoform were then analyzed using atomic absorption spectrophotometry for Ni, Cr, Cu, An, Fe, Al, and Mg. Each sample showed a different concentration profile as a function of density, and a number of useful conclusions concerning characterization of elemental distribution were obtained. From the density distributions of elements in soil, the maximum value was found for all elements in the density range of 2.2 $\sim 2.9g.cm^{-3}$, including the density of $SiO_2$. However, the distribution of metallic compounds with the density lower than $2.2g.cm^{-3}$ was prevalent in urban roadway dust, urban dust fall, and airborne particulate matter. And the density distribution curves of these urban dusts also have the higher distribution at the density of 2.2 - 2.9g.cm^{-3}$, including the density of wind-blown silica. This tendency generally was prevalent in the natural source elements, such as Al, Fe, Mn, and Mg. The maximum values were found in the density ranges of 1.3 $\sim 2.2g.cm^{-3}$ from the density distribution of elements in oil fired flyash. These distributions of anthropogenic source elements, such as Zn, Ni, Cu, and Cr were higher predominately than those of natural source elements. And the higher distribution was found in the density range of $2.2 \sim 2.9g.cm^{-3}$ from the density distribution of elements in coal and soft-coal fired flyash. These distributions showed similar patterns to soil. But anthropogenic source elements somewhat predominated at the density ranges of $1.3 \sim 2.2g.cm{-3} and 2.9g.cm^{-3}$ to soil. Therefore the higher distribution of anthropogenic source elements in the density ranges of $1.3 \sim 2.2g.cm^{-3} and 2.9g.cm^{-3}$ was considered as anthropogenic origin.

• 공업화학
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• 제2권2호
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• pp.185-191
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• 1991

한국 대륙붕 블럭 VI의 돌고래-1공에서 채취한 근원암의 화학성분 및 특성에 관해 조사하였다. 유징분석기를 사용하여 가스, 기름 및 총추출유기물의 양을 구했으며 총추출 유기물의 양은 0.59 %이었다. 비투멘의 양과 분자량은 용매추출법과 겔투과 크로마토그래피에 의해 구했으며, X-선회절법, 적외선분광법 및 열무게 측정법으로 물리화학적 성질을 고찰하였다. 분석 결과로부터 돌고래-1공의 시료는 미미한 석유근원암으로 평가되었다.

• 한국가스학회지
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• 제26권6호
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• pp.24-29
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• 2022

이 논문은 LPG 자동차의 캠축베어링 시일의 오일누설, 컴퓨터커넥터 핀 손상에 의한 접촉불량, 베이퍼라이저 배부불량으로 인한 고장사례에 대하여 현상을 분석, 연구한 것이다. 첫 번째 사례는 실린더 헤드를 분해하여 확인한 결과 타이밍 시스템에서 가까운 엔진의 흡기캠축의 베어링과 시일의 조립부 손상으로 인해 이 부위로 엔진오일이 누설되는 것을 확인하였다. 두 번째 사례는 엔진컴퓨터로 공급되는 자동차의 시동을 제어하는 전원선의 커넥터 핀이 손상되어, 전원이 공급되지 않아 시동이 꺼진 것을 확인하였다. 세 번째 사례는 베이퍼라이저 내부에 이물질의 퇴적으로 인해 가스의 흐름이 원활하지 못하여 엔진의 부조화현상이 발생되었다. 결국, 베이퍼라이저에서 믹서로 적은 양의 가스를 공급하게 되고, 믹서의 스로틀 열림량을 제어하는 컴퓨터는 그 열림량만큼 공기를 공급하게 됨으로써 연소실에서 혼합기는 희박한 상태가 되어 엔진의 적정출력을 내지 못하는 것을 확인하였다. 따라서, 자동차가 최적의 운전조건이 될 수 있도록 자동차관련 시스템의 관리를 철저하게 해야한다.

• Asian-Australasian Journal of Animal Sciences
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• 제22권9호
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• pp.1311-1319
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• 2009

An experiment was conducted to determine the effects of soybean oil supplementation replacing tallow in pig diets at different stages of growth. One hundred and twenty crossbred (Landrace${\times}$Yorkshire${\times}$Duroc) pigs weighing 18 kg on average were selected. Pigs were randomly allotted to 12 pens of 10 pigs (5 pigs of each sex) each. Three pens were assigned to each of the four treatments: TA; tallow diet, TA-SO-80; switched from tallow to soybean oil diet at 80 kg average body weight, TA-SO-45; switched from tallow to soybean oil diet at 45 kg average body weight, and SO; soybean oil diet. Treatment SO was significantly lower in ADG than tallow diets (TA, TA-SO-80 and TA-SO-45) during the grower period (18 to 45 kg). However, treatment SO showed greatest compensation in ADFI and ADG during the finisher-2 period (after 80 kg body weight). ADFI and ADG and Gain/Feed for the total period were not significantly different among treatments. Loin area, back fat thickness, firmness and melting point of back fat were not significantly different. The levels of total cholesterol and low density lipoprotein+very low density lipoprotein cholesterol in serum were significantly lower in treatment SO than in treatments TA-SO-45, TA-SO-80 and TA. The level of serum triglyceride linearly increased as the length of the tallow feeding period increased. Serum immunoglobulin-G (IgG) level was significantly higher in the soybean oiltreatment than in other treatments. Major fatty acid composition of short rib muscle and back fat were significantly influenced by treatments. Contents of ${\alpha}$-linolenic acid (C18:3) and docosahexaenoic acid (DHA, C22:6) linearly increased as the soybean oil feeding period increased. In conclusion, soybean oil can be supplemented to the diet of pigs without significant effects on growth performance and carcass characteristics. The level of polyunsaturated fatty acids (PUFA), especially $\omega-3$ fatty acids in the carcass was increased by soybean oil supplementation.

• 한국응용과학기술학회지
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• 제24권2호
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• pp.196-204
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• 2007

The objective of this study was to determine the effect of dietary oils on the levels of the ${\gamma}-linolenic$ acid in chicken meat lipids. Three hundred ten five, 1-d old, male, Ross strain, broiler chicks were fed for 35 d to compare diets containing evening primrose oil(EPO) and hemp seed oil(HO) to a control diet. Fatty acid composition of lipid from chicken skin, thigh and breast muscle were determined at the end of the trial. The level of ${\gamma}-linolenic$ acid of lipids from chicken meat fed diets containing EPO or HO was significantly higher than that of the control group(p<0.05). The level of ${\gamma}-linolenic$ acid of lipids from chicken skin was highest in the group, which had been fed the EPO 0.85%, followed in order by EPO 0.7%, 0.5%, EPO mixed oil, HO and HO mixed oil. There was a significant difference in the level of ${\gamma}-linolenic$ acid of chicken skin between the control and treatment groups(p<0.05). The level of ${\gamma}-linolenic$ acid of lipids from chicken thigh muscle was also similar to skin, and significantly higher than that of the control group(p<0.05). The level of ${\gamma}-linolenic$ acid of lipids from chicken breast muscle was highest in the group, which had been fed the EPO 0.5%, followed in order by EPO 0.7%, 0.85%, HO 0.5% and HO mixed oil. There was a significant difference in the level of ${\gamma}-linolenic$ acid of chicken breast muscle between the control and treatment groups(p<0.05).

• 생명과학회지
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• 제18권12호
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• pp.1665-1670
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• 2008

콩의 oil은 식량유지 자원으로서 매우 중요한 부분을 차지하고 있으며, 전세계 식용유의 22%를 콩 oil이 차지하고 있으며 식품에서 매우 중요한 영양학적인 요소이다. 이중 불포화지방산은 지방산 중에서 종자 구성물질들은 polygenetic 형질들로 되어있다. 본 시험은 큰올콩과${\times}$신팔달콩의 RIL 계통과 SSR marker를 이용하여 유전자지도를 작성하고, 이를 바탕으로 불포화지방산의 함량과 관련된 양적형질 유전자좌(QTLs)를 탐색하였다. Oleic acid 함량과 관련된 QTLs는 7개의 연관군에서 8개의 마커가 확인되었으며, linoleic acid는 5개의 연관군에서 7개의 마커가 확인되었다. 그리고 linolenic acid는 5개의 연관군에서 각각 하나씩의 마커가 확인되었다. 본 시험의 결과 불포화지방산에 공통적으로 나타난 QTL은 연관군 C1과 L이었다.

• Asian-Australasian Journal of Animal Sciences
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• 제26권5호
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• pp.705-710
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• 2013

This study was conducted to determine the effects of three different fat sources and their combination on growth performance, carcass traits and intestinal measurements of broiler chickens reared to 42 d of age. Two hundred day-old male broiler chicks (Ross 308) were randomly assigned to one of five treatments with four replicates of 10 chicks based on a completely randomized design. The dietary treatments consisted of 4% added fat from three different sources and their combination as follows: T, diet containing 4% tallow; CO, diet containing 4% canola oil; SFO, diet containing 4% sunflower oil; TCO, diet containing 2% tallow+2% canola oil; TSFO, diet containing 2% tallow+2% sunflower oil. Dietary fat type affected significantly BW and gain as well as feed efficiency in birds fed the TCO diets compared with those fed the other diets. Dietary fat type also modified meat yield, resulting in a higher breast and drumstick yields in the birds fed TCO and TSFO diets, respectively. Most of internal organ relative weights and small intestine measurements were not influenced by dietary treatments, except for the abdominal fat pad weight that was lower in birds fed SFO and for small intestinal length that was influenced by fat source. Results from the current study suggested that the supplementation with a combination of vegetable and animal fat sources in broiler diet supported positively growth performance and carcass parameters.

• Journal of Animal Science and Technology
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• 제62권2호
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• pp.187-197
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• 2020

The present study was conducted to evaluate the effects of black soldier fly larvae oil (BSFLO) from the black soldier fly larvae (BSFL) as a partial or total replacement of soybean oil (SBO) on growth performance, fatty acid (FA) profile, and meat quality of broiler chickens from 1 to 5 wk of age. A total of 210 male broiler chickens (Ross 308) at one-day of age were randomly allotted to 3 dietary treatments (10 replicates and 7 birds/group): a basal control diet (CON), the basal diet in which the SBO was replaced by 50% (50 BSFLO) or 100% (100 BSFLO) of BSFLO. The growth performance, physical measurements and chemical traits of leg meat, and sensory analysis of breast meat were not influenced by diets. However, the relative weight (g/kg) of gizzard of CON was significantly higher (14.85, 12.52, and 13.02 for CON, 50 BSFLO, and 100 BSFLO; p < 0.05) than that of other treatments. As expected, the FA profile of breast meat was affected by BSFLO inclusion. The proportion (%) of saturated fatty acid (SFA) was increased (27.16, 27.58, and 28.72 for CON, 50 BSFLO, and 100 BSFLO; p < 0.05) by BSFLO inclusion and the percentage (%) of MUFA was also increased (43.36, 44.58, and 48.55 for CON, 50 BSFLO, and 100 BSFLO; p < 0.01). On the contrary, the proportion (%) of PUFA was decreased (29.49, 27.84, and 22.74 for CON, 50 BSFLO, and 100 BSFLO; p < 0.01). In conclusion, the present study suggests that the replacement of BSFLO did not show an adverse effect on growth performance and it could be an ingredient as a dietary fat source for a broiler diet.