• Asian-Australasian Journal of Animal Sciences
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• 제26권5호
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• pp.646-653
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• 2013

Four crossbred Sindhi heifers with an average body weight (BW) of 135 kg and a mean age of 17 months were used to investigate the effect of feeding different combinations of rice straw and ensiled water hyacinth (EWH) supplemented with a source of protein in the form of cottonseed cake (CSC) on intake and digestibility. Four treatments consisting of graded levels of EWH were arranged in a $4{\times}4$ Latin square. The levels of EWH were set at: 0 (EWH0), 15 (EWH15), 30 (EWH30), and 45% (EWH45) of an expected total dietary dry matter (DM) intake of 30 g total DM per kg BW per day. Rice straw was offered ad libitum, while CSC was given at a fixed level of 5 g DM/kg body weight (BW). Voluntary intake and digestibility were measured consecutively in the 4 experimental periods which each lasted 28 days. The crude protein (CP) content of EWH, rice straw and CSC were 174, 53 and 370 g/kg DM, respectively. Rice straw had the highest neutral detergent fibre (NDFom) content (666 g/kg DM), followed by EWH (503 g/kg DM) and the lowest content was 418 g/kg DM in the CSC. The actual EWH contents in the consumed diets were 0, 17, 32 and 52% for EWH0, EWH15, EWH30 and EWH45, respectively. Rice straw intake decreased with level of EWH offered from 3049 for EWH0 to 1014 g/day for EWH45. Crude protein intake was 16, 25 and 33% higher (p<0.001) in EWH15, EWH30 and EWH45 treatments, respectively, as compared to EWH0. Digestibility of organic matter (OM), CP, NDFom and acid detergent fibre (ADFom) increased with increasing level of EWH offered. The highest OM digestibility (72.2%) was found for treatment EWH45 and the lowest (47.4%) for treatment EWH0. In spite of similar dietary CP contents, CP digestibility increased by 21 (EWH15), 31 (EWH30) and 40% (EWH45) with increasing level of EWH in comparison with treatment EWH0. It is concluded that increasing level of EWH in cattle diets considerably improved CP intake and digestibility of nutrients.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 1992년도 수공학연구발표회논문집
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• pp.133-141
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• 1992

A three water-intake structure designed to built along the right bank of the Missouri River near Chesterfield, Missouri was model-tested at an undistorted scale of 1:5. Although the discharge capacity of each of six pumps to be installed is only 21,000 gpm, the model indicated strong flow circuation and unstable free-surface conditions as flow entered the two-pump bay through a narrow sluice opening at an angle. Strong free-surface vartices were also observed in the model. The sump modifications developed in the study included an array of baffle bars, a perforated plate, floor splitters, and floor-corner fillets. The solutions developed in this study could be applied to other pump sumps with multiple pump units.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1324-1326
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• 1999

This paper demonstrates the insulation-destruction of high-voltage-motors for intake pump. To analyze the causes of damage in motors, electrical, mechanical and environmental fiery-development were investigated. The insulation-destruction of high-voltage-motors are generally due to the fiery-stress by void where composite materials such as mica/epoxy are used. But this paper shows that electrical and mechanical stresses can be the main reason of the damage, too.

• 대한토목학회논문집
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• 제29권3B호
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• pp.221-230
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• 2009

국내 주요 상수 취수원은 동일한 하천 및 호수에 하수 처리장이 위치해 있어 처리 방출수로 인한 악영향을 받게 된다. 또한 하천을 따라 건설된 도로나 교량에서 발생하는 교통사고나 수질 오염사고로 인한 하천 내의 오염물 유입은 취수장 운영에 큰 어려움을 주게 된다. 특히 우리나라 주요 상수원에 해당하는 팔당호의 경우 호수면적에 비해 유역면적이 상당히 크기 때문에 다양한 수질 오염사고에 노출되어 있다. 따라서 사전에 발생 가능한 수질사고를 모의하고 이에 대한 대책을 모색하는 일이 매우 중요하다. 본 연구에서는 팔당호 주변에서 발생할 수 있는 수질 오염사고에 대한 수질모의를 수행하였다. 2차원 수치모형을 이용하여 사고로 유입된 오염물질의 혼합거동을 모의하였고, 팔당호에 위치한 주요 취수장에 미치는 영향을 분석하였다. 이를 위해서 2차원 흐름모형인 RMA-2를 이용하여 유속장을 모의하고, 이 결과를 2차원 하천수질 해석모형인 RAM4에 입력하여 오염물질의 시간에 따른 거동을 분석하였다. 갈수기 수질사고 발생시 저감방안으로써 남한강과 북한강의 유량증대에 따른 오염물질의 희석 및 수세 효과에 대해 분석하였다. 분석결과 유량증대에 따라 오염물질의 최대 농도는 더 높아지면서 더 빠르게 이동하는 현상을 관찰할 수 있었다. 따라서 오염물질이 주입된 지점에서의 초기 희석 효과보다는 빨라진 흐름에 의한 수세 효과가 훨씬 더 크게 나타난 것으로 판단된다. 이를 통해 독성 오염물질로 인한 수질사고 발생시 유량증대에 의한 수세 효과가 취수장 운영에 있어 유리한 대책이 될 수 있음을 확인할 수 있다.

• Nutrition Research and Practice
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• 제18권4호
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• pp.534-543
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• 2024

BACKGROUND/OBJECTIVES: Studies on the impact of dietary fiber intake on kidney stones are few, and their results were controversial. This study aimed to explore the association between dietary fiber intake and kidney stones in the nationally representative population of the USA. SUBJECTS/METHODS: This cross-sectional research included 8,588 participants from the National Health and Nutrition Examination Survey, 2011 to 2018. Information regarding dietary fiber intake was obtained from a 24-h recall survey. Participants were categorized into different dietary fiber intake tertiles according to the average of 2 days of dietary recall data. The outcome was self-reported kidney stones. After adjusting for the traditional risk factors, a multivariate logistic regression model was used to examine the association between dietary fiber intake and kidney stones. RESULTS: Eight hundred seventy-two participants had kidney stones. The weighted prevalence (SE) of kidney stones in the lowest tertile, medium tertile, and highest tertile of dietary fiber intake was 11.8% (0.8%), 10.3% (0.8%), and 9.1% (0.8%), respectively. After adjusting for age, sex, race and ethnicity, education level, smoking status, alcohol consumption, physical activity, body mass index, hypertension, diabetes, dyslipidemia, daily water intake, chronic kidney disease stage 3-5, and total energy intake, participants with the highest tertile of fiber intake had a significantly lower risk of kidney stones (odds ratio [OR], 0.68; 95% confidence interval [CI], 0.48-0.95) compared to those in the lowest tertile. Every 5 g/day increment in dietary fiber intake was associated with a significant decrease in risk of kidney stones (OR, 0.90; 95% CI, 0.83-0.98). CONCLUSION: An increase in dietary fiber intake was associated with a lower risk of kidney stones, suggesting adults should be encouraged to maintain an adequate dietary fiber intake to prevent the development of kidney stones. Our results provide evidence to formulate nutrition management strategies for the prevention of kidney stones.

• 한국분무공학회지
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• 제1권1호
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• pp.28-34
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• 1996

Study on the mechanism of droplet transport and the droplet eddy diffusivity in the intake manifold of internal conbustion engine with carburetor has been carried out in this paper The theory and experiments were studied and performed respectively, to elucidate the mechanism and to measure typical rates of deposition, on the walls of a straight type intake manifold, of water droplets suspended in a turbulent air streams. Accordingly, the results are that Mechanism of a spray transport to the walls is caused by the fluctuation component of radial velocity. Deposition rate of a spray on the walls is mainly dependent upon air velocity and mean diameter of spray, and Droplet eddy diffusivity in the intake manifold is around $80\sim105cm^2/sec$.

• 생태와환경
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• 제36권4호통권105호
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• pp.467-472
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• 2003

본 연구에서는 상수원수 취수장의 취수구로 유입되는 조류 군체의 양을 물리적으로 억제할 수 있는 조류 펜스를 개발하고, 현장에 적용 및 평가하였다(2001년 6-9월). 펜스를 설치한 후 펜스 안팎의 식물플랑크톤 생체량은 통계적으로 유의한 차이를 나타내었다. 분산 분석의 결과 설치 1일 후의 chl. a는 모든 수심 (0, 1,2 m)에서 유의한 차이를 보였으며 (모든 수심에서 0.001 > p ,각 수심별 r= 16), 특히 표층과 수심 1m에서 가장 큰 차이를 보였다. 하지만 조류 저감 효과는 설치 후 3-5일이 지나면서 감소하였다. 조류 펜스의 물리적 유입 저감 효과의 지속성 유지를 위해서는 효과적인 설치 및 유지관리 방안(예, 기계적인 설치 및 주기적인 역세척 등)이 모색되어야 하며, 생태 모형을 이용하여 대번성 시기 예측이 가능할 경우 훨씬 효과적으로 조류의 유입 차단이 가능할 것으로 보인다.

• 농업과학연구
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• 제47권3호
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• pp.597-604
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• 2020

Exposure to heat stress (HS) has negative effects on pig production and health. Plasma concentrations of amino acids (AAs) can be used as indicators of HS. Therefore, this study was conducted to evaluate the effect of acute HS on feed intake, water drink, and plasma AAs in pigs. A total of 6 growing pigs (n = 6, 3 boars and 3 gilts) were raised in thermal neutral (TN; 25℃) conditions for the 5-d adaptation period as a control. After the adaptation, pigs were exposed to HS at 33℃ (HS33) for 24 h. All the pigs were fed the same diet formulated to meet or exceed predicted requirements during the whole experimental period. Blood samples were collected after the adaptation and heat treatment to verify the AAs. Measurements were the average daily feed intake (ADFI), average daily water intake (ADWI), water loss, tumor necrosis factor (TNF)-α, nitrate, total nitric oxide, and AAs in the plasma samples. Data were analyzed using the PROC GLM of SAS. HS33 had a lower ADFI (p < 0.05) and a tendency for an increased ADWI and water loss compared to TN. The level of TNF-α was significantly decreased (p < 0.05) in HS33. HS33 had a lower concentration of histidine and sarcosine compared to TN; however, there were no differences in the levels of nitrates and total nitric oxide. In conclusion, the results of this study show the differential effect of HS on the plasma concentration of AAs. We expect that the changed AAs could be potential indicators of HS.

• Asian-Australasian Journal of Animal Sciences
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• 제14권7호
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• pp.1014-1018
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• 2001

Pigs respond to extreme temperature (very cold or hot) by physiological and nutritional adjustments. Yet little is known about the effects of different environmental temperature (thermoneutral in the highland area, and hot temperature in the coastal area) where pigs are maintained on the performance of the pigs. Ten pigs each (10 pairs of littermates) were assigned to two treatments (2 locations): highland area (control=CA) or coastal area (hot/heat stress=HS). Experimental design was Paired 't' test. HS pigs had higher average daily water intake (p<0.05) compared to CA pigs (6,05 vs 3.89 kg/d), CA pigs had higher feed intake compared to HS pigs (2.9 vs 1.95 kg/d, p<0,05). CA pigs had higher daily gain compared to HS pigs (0.72 vs 0.58 kg/d, p<0.05). Feed conversion was not significantly different between CA pigs and HS pigs. The digestibility of dry matter, N, Na, K, Mg, CI, Ca and P was not significantly affected by the treatments. High environmental temperature in the coastal area (heat stress) increased water intake, decreased voluntary feed intake and daily gain of the pigs. The results demonstrate that different environmental temperature in the coastal area (heat stress) and highland area (control) had no pronounced effect on digestibility of nutrients.

• 한국유체기계학회 논문집
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• 제3권4호
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• pp.52-58
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• 2000

The numerical study on the waterhammer was carried out for the intake pumping station of the metropolitan water supply 6th stage project. Because the waterhammer problems as a result of the pump power failure were the most important, these situations were carefully investigated. The surge tank and the stand pipes effectively protected the tunnels md the downstream region of pipeline from the pressure surge. In case the moment of inertia of the pump and motor was above $5080\;kg{\cdot}m^2$, the column separation did not occur in the pipeline between the pumping station and the inlet of 1st tunnel. As the moment of inertia increased, the pressure surges decreased in the pipeline conveying raw water. The pump control valve was chosen as the main surge suppression device for the intake pumping station. After power failure, the valve disc should be rapidly closed in 2.5 seconds and controlled the final closure to 15 seconds by the oil dashpot. If the slamming happened to the pump control valve, there was some danger of this system damaging. As the reverse flow through the valve increased, the upsurge extremely increased.