• 제목/요약/키워드: Reduction rates

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고분자용액에 의한 유체수송관벽의 저항감소 -III. 저항감소유체의 입구흐름 영역에 대한 고찰- (Drag Reducton of Pipe Wall For Fluid Flow due to Injected Polymer Solution - III. Consideration of Entrance Region Flow of Drag Reducing Fluids-)

  • 김영보;유경옥
    • 한국화재소방학회논문지
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    • 제5권2호
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    • pp.21-35
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    • 1991
  • As a part of studies of drag reduction phenomenon, at the entrance flow region of abrupt contraction tube flowing water, dilute and concentrated drag reducing polymer solutions contraction losses are estimated experimentally. Futher more, entrance lengths are considered theoretically and are measured experimentally. In the present experiment, fluid temperature is fixed l$0^{\circ}C$ and flow rates are 3,000

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Review of outcomes of using lower ethanol concentration (83%) in percutaneous ultrasound-guided renal cyst sclerotherapy in dogs

  • Sanghyeon Yoon;Jungmin Kwak;Deokho Im;Hakyoung Yoon
    • Journal of Veterinary Science
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    • 제24권5호
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    • pp.61.1-61.12
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    • 2023
  • Background: Percutaneous renal cyst sclerotherapy (PRCS) as a treatment for renal cysts is usually performed with a high concentration of ethanol (≥ 90%). This study reviewed cases in which a lower concentration of ethanol (83%) was used for the procedure in dogs. Methods: Records of cases of renal cysts treated by sclerotherapy using 83% ethanol in dogs were reviewed. Outcomes of the treatment were evaluated by comparing volumes of renal cysts before the procedure and the volumes after treatment, using ultrasound images with the volume reduction rates classified as follows: < 50% of initial volume (failed); ≥ 50% but < 80% of initial volume (partial success); ≥ 80% but < 95% of initial volume (great success); ≥ 95% of initial volume (complete success). Results: Out of nine dog kidneys, renal cysts sclerotherapy with 83% ethanol achieved partial success in one kidney, great success in four, and complete success in the other four. No side effect was observed. The mean of the volume-reduction rates was 90.00 ± 11.00 while the minimum and maximum reduction rates were 65% and 100%, respectively. Conclusions: The lower ethanol concentration (83%) is good for disinfecting kidneys in PRCS.

(-)-Hydroxycitrate의 식이 투여가 흰쥐의 식이 섭취량, 체중, 지방대사 및 합성에 미치는 영향 (Influence of (-)-Hydroxycitrate on food Intake, Body Weight and Lipogenesis in Rats)

  • 김상배
    • Journal of Nutrition and Health
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    • 제30권2호
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    • pp.123-131
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    • 1997
  • The influence of (-0-Hydroxycitrate(HCA), shown to be a competitive inhibitor of adenosine 5-triphosphate(ATP) citrate lyase, on food intake and body weight, serum triglyceride and cholosterol level, in vivo rates of fatty acid and cholesterol synthesis, and fat cell number and size was investigated. 3 groups of female, 5 weeks old Sprague Dawley rats, 8 animals each, were ad libitum meal-fed or pair-fed(3 hours from 10 : 00 to 13 : 00) AIN based high glucose diet for a total period of 8 weeks. Providing normolipidemic rats orally with 400mg of HCA formula containing approximately 20mg of HCA 1 hour prior to daily feeding schedule significantly depressed in vivo hepatic rates of fatty acid and cholesterol synthesis in the liver and adipose tissue. Serum triglyceride and cholesterol levels were significantly reduced by HCA. At the end of treatment period, the rats administered with HCA resulted in a significantly reduction in body weight gain. The reduction in weights was attributable to a significant decrease in fat cell size with a smaller extent, but not significant, reduction in fat cell number. Rats receiving HCA demonstrated less food intake than the controls ; however, this decreased caloric intake was not fully responsible for the HCA induced depression of hepatic and adipocytic lipogenesis, since experiment using pair-fed cojntrol rats showed, less magnitude but similar results. Both a anorectic and an antilipogenic properties of HCA seem to be responsible for this weight reduction activity of HCA. The outcome of this study suggest that metabolic regulation may be a feasible approach to the control of obesity and hyperlipidemia.

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Effect of $TO_3$ and $NO_2$ on Net Photosynthesis, Transpiration and Accumulation of Nitrite in Sunflower Leaves

  • Park, Shin-Young;Lee, Sang-Chul
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • 제3권2호
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    • pp.121-129
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    • 1999
  • Photosynthesis and transpiration rates were simultaneously measured in attached sunflower leaves(Helianthus annuusL. cv. Russian Mammoth) during exposure to $NO_2$ and $O_3$ to determine the effect of mixed gan on photosynthesis and the stomatal aperture. The application of $O_3$ alone reduced both the net photosynthetic and transpiration rates. An analysis of the $CO_2$ diffusive resistances indicated that the main cause affecting photosynthesis reduction during $O_3$ exposure was not the internal gas phase of the leaf $(rCO_2^{liq})$ but rather the liquid phase or mesophyll diffusive resistance $(rCO_2^{liq})$, suggesting that there is a very concomitant relation between photosynthetic reduction and $rCO_2^{liq}$. The application of NO2 alone caused a marked reduction of the net photosynthesis yet no significant reduction of transpiration, indicating that NO2 affects the $CO_2$ fixation processes with no inluence on the stomatal aperture. A greter reduction in the photosynthesis of sunflower plants was caused by the application of $NO_2$ alone as compared to a combination of $NO_2$ and $O_3$. $NO_2$ alone reduced the photosynthetic rate by 90%, whereas a mixture of NO2 and O3 reduced it by 50%.

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수도권 지역별 목표대기질 달성을 위한 오염배출 삭감율 산정 연구 (An Estimation of Emission Reduction Rates to Achieve the Target Air Quality in Seoul Metropolitan Area)

  • 김정수;김지영;홍지형;정동일;반수진;박상남
    • 환경영향평가
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    • 제16권1호
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    • pp.1-13
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    • 2007
  • This study was carried out to estimate the emission reduction rates for the regional allowable emissions by special measures to achieve the target air quality in Seoul Metropolitan Area (SMA). A modeling system was designed to validate the details in enforcement regulations set up by local governments based on the current status and plans for air quality improvement. Modeling system was composed of meteorological model (MM5), emission model (SMOKE), and air quality model (CMAQ). Predicted results by this system show quiet well not only daily air pollutants concentration but also the tendencies of wind direction, wind speed and temperature. To achieve the target air quality in Seoul Metropolitan Area (SMA), emission allowances are estimated by seasons and regions. Referring to the base year 2002, it was estimated that emission reduction rates to achieve the intermediate goal in 2007 were 14.2% and 16.6% for NOx and $PM_{10}$, respectively. It was also estimated that 52% of NOx and 48% of $PM_{10}$ reductions from the base year 2002 would be required to accomplish the air quality improvement goal of 22 ppb for $NO_2$, and $40mg/m^3$ for $PM_{10}$ in year 2014. To improve $NO_2$ and $PM_{10}$ concentration through emissions reduction policies, it was found that emissions reduction for the on-road mobile sources would be the most effective in SMA.

Comparing Chewable and Manual Toothbrushes for Reducing Dental Plaque: A Pilot Study

  • Jeong, Moon-Jin;Shin, Hye-Sun;Jeong, Soon-Jeong;Lim, Do-Seon
    • 치위생과학회지
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    • 제17권3호
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    • pp.267-274
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    • 2017
  • This study aimed to compare the effectiveness of chewable toothbrush and manual toothbrush and provide basic data for recommendation of the chewable toothbrush in specific groups and situations. A total of 20 subjects participated in this study (rolling method, 10; non-rolling method, 10). After professional prophylaxis, participants used the manual toothbrush to brush their teeth for 3 minutes. After a 7-day wash-out period, participants used the chewable toothbrush according to the manufacturer's instructions. Pre- and post-plaque indexing of the teeth was performed. The dental plaque index was assessed using the Turesky Modification of the Quigley-Hein Plaque Index (TMQHPI) for amount of plaque and Silness-Loe Plaque Index (SLPI) for plaque thickness. The difference between pre- and post-dental plaque index was analyzed using a paired t-test and the Wilcoxon signed-rank test. The Mann-Whitney U test was also used to compare the dental plaque index reduction rates. The dental plaque index differed significantly between the chewable toothbrush and the manual toothbrush. The TMQHPI reduction rate was significantly different between the rolling and non-rolling method groups for the manual toothbrush but not the chewable toothbrush. The difference in SLPI reduction rate between the rolling and non-rolling method groups was significant for the manual toothbrush but not for the chewable toothbrush. Differences in the dental plaque index reduction rates between the chewable and manual toothbrushes were not significant in the non-rolling method group. The results of this study showed higher reduction rates in dental plaque with manual toothbrush use than with chewable toothbrush use. However, the non-rolling method group did not show statistically significant differences according to toothbrush type. The present study showed that a chewable toothbrush can be an alternative to a manual toothbrush for individuals who have difficulty using the generally recommended rolling method.

약제 살포 후 경과일수별 세척에 의한 방울토마토의 잔류농약경감 (Reduction of pesticide residues in/on mini-tomato by washing at the different harvest days after pesticide spray)

  • 권혜영;김진배;이희동;임양빈;경기성;권오경;최달순;최주현
    • 농약과학회지
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    • 제10권4호
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    • pp.306-312
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    • 2006
  • 시설하우스에서 방울토마토를 재배하여 농약 살포 후 경과일수별 세척시험을 실시하여 농약의 이화학적 특성별 세척에 의한 잔류농약의 제거율을 구하였다. 방울토마토에 3종의 시판농약을 살포한 후 수돗물로 세척한 결과 침투이행성 약제인 oxadixyl은 약제살포 후 0일에 61%, 5일에 11%, 7일에 4% 제거되었고 침투성약제인 thiophanate-methyl은 89%, 89%, 79%, 비침투성인 chlorothlaonil의 경우 84%, 84%, 88% 제거되었다. 세정제인 $Sur-ten^{(R)}$용액 세척시는 약제살포 후 0일과 5일에 oxadixyl 81%, 55%, thiophanate-methyl 95%, 91%, chlorothlaonil 97%, 98%가 각각 제거되었다. 제거율에 있어서 부성분의 영향을 평가하기 위해 시판농약과 달리 같은 부성분으로 제조된 시제품을 살포 한 후 수돗물 세척시에는 약제살포 후 0, 5, 7일에 각각 oxadixyl 76%, 66%, 43%, thiophanate-methyl 91%, 83%, 82%, chlorothlaonil 65%, 68%, 82% 제거되어 경과일수별 제거 양상은 시판농약과 비슷하였으나 제거율은 달라 세척시 원제 및 부성분함량의 영향이 있는 것으로 생각되었다.

A New Pruning Method for Synthesis Database Reduction Using Weighted Vector Quantization

  • Kim, Sanghun;Lee, Youngjik;Keikichi Hirose
    • The Journal of the Acoustical Society of Korea
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    • 제20권4E호
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    • pp.31-38
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    • 2001
  • A large-scale synthesis database for a unit selection based synthesis method usually retains redundant synthesis unit instances, which are useless to the synthetic speech quality. In this paper, to eliminate those instances from the synthesis database, we proposed a new pruning method called weighted vector quantization (WVQ). The WVQ reflects relative importance of each synthesis unit instance when clustering the similar instances using vector quantization (VQ) technique. The proposed method was compared with two conventional pruning methods through the objective and subjective evaluations of the synthetic speech quality: one to simply limit maximum number of instance, and the other based on normal VQ-based clustering. The proposed method showed the best performance under 50% reduction rates. Over 50% of reduction rates, the synthetic speech quality is not seriously but perceptibly degraded. Using the proposed method, the synthesis database can be efficiently reduced without serious degradation of the synthetic speech quality.

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대기오염 방지대책으로서 지역난방의 효과분석에 관한 연구 (A Study on the Effects of the District Heating as an Air Pollution Control Strategy)

  • 전의찬;김정욱
    • 한국대기환경학회지
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    • 제6권1호
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    • pp.51-56
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    • 1990
  • This Study shows the effect of the district heating on the $SO_2$ concentration reduction. In order to analyze the effect of the district heating, three alternatives were set up as follows; Alternative I represented present central heating system, and Alternative II and Alternative III represented district heating system of which the scale were different from. The concludions of this study are as follows; In case of the Alternative II and III, annual average $SO_2$ concentration are reduced by 9.0% and 14.6% respectively, and winter season $SO_2$ concentrations are reduced by 12.2% and 15.8% respectively, at the highest points. The average reduction rates of $SO_2$ concentration in the district heating area are about the same as the reduction rates at the highest points. Also, it was found that using the district heating system, the ground level $SO_2$ concentrations could be reduced within the area of 5 to 10 km radius.

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A study on interaction effect among risk factors of delirium using multifactor dimensionality reduction method

  • Lee, Jong-Hyeong;Lee, Yong-Won;Lee, Yoon-Seok;Lee, Jea-Young
    • Journal of the Korean Data and Information Science Society
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    • 제22권6호
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    • pp.1257-1264
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    • 2011
  • Delirium is a neuropsychiatric disorder accompanying symptoms of hallucination, drowsiness, and tremors. It has high occurrence rates among elders, heart disease patients, and burn patients. It is a medical emergency associated with increased morbidity and mortality rates. That s why early detection and prevention of delirium ar significantly important. And This mental illness like delirium occurred by complex interaction between risk factors. In this paper, we identify risk factors and interactions between these factors for delirium using multi-factor dimensionality reduction (MDR) method.