• Title/Summary/Keyword: Decrease rate

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Dietary Evaluation and Protein Catabolic Rate in Maintenance Hemodialysis Patients (혈액투석환자의 식이조사 및 Protein Catabolic Rate에 관한 연구)

  • 장유경
    • Journal of Nutrition and Health
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    • v.25 no.3
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    • pp.256-263
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    • 1992
  • As various metabolic alterations develope in uremic patients. their diets need to be restricted, Furthermore medical complications with accompanying anorexia result in further complications and decrease in body strength. To assess the nutritional status of hemodialyzed patients we performed evaluation for dietary intake and protein catabolic rate(PCR) For 24 clinically stable male patients undergoing maintenance hemodialysis dietary intake was estimated by 3-day food record method and PCR was calculated with blood urea nitrogen at pre and post hemodialysis. The results were as follows : 1) Average daily energy and protein intake were 26.7$\pm$5.1kcal/kg of body weight. 0.95$\pm$0.19 g/kg of body weight respectively. 2) Protein catabolic rate calculated from interdialysis blood urea nitrogen levels was 1.00$\pm$0.20g/kg of body weight. Protein catabolic rate was correlated with the amount of Protein intake(r=0.44 p<0.05) 3) Relative body weight(RBW) of the subjects was smaller than that of healthy man without hemodialysis. Calorie and protein intake and protein catabolic rate were significantly different (p<0.05) between patients with lower RBW(<90% of ideal body weight) and those with normal RBW(90~110% of ideal body weight) and those with normal RBW(90~110% of iedal body weight) 4) The duration of hemodialysis did not have a significant effect on the nutritional status of the subjects.

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The Evaluation of Geotextiles by Ultraviolet(UV) Effect during the Landfill Construction (폐기물 매립지의 부직포 포설시 UV 영향에 대한 평가)

  • 고재학;이재영
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 1998.11a
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    • pp.206-215
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    • 1998
  • Using of geosynthetics with linear materials(sand, gravel, clay soil) is rapidly increased in landfill. With geosynthetics, geotextiles often expose to solar radiation(Ultraviolet) on long terms during the installation. In this paper, the results will represent the strength retention rate and tensile retention rate of geotextiles between outdoor exposed and protected by 15cm thickness of soil. As a result of cumulating solar radiation in geotextiles was increased, the strength retentions rate of P.P(500g/$m^2$), P.P(700g/$m^2$) and P.P(1000g/$m^2$) were decreased and the lower weight of unit area of geotextiles, the faster decrease of strength retention rate. P.E.T(600g/$m^2$) was showed a distinctive trend that the strength retention rate increased. The tensile retention rate of tested geotextiles was decreased during the simulation. However, the strength and tensile retention rate of geotextiles covered by soil had changed insignificantly. Therefore, it can surmise that the soil covering will help geotextiles to be protected from UV effecting

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Studies on the Properties of the Plasma TEOS $SiO_2$ Film (PECVD TEOS $SiO_2$막의 특성에 관한 연구)

  • 이수천;이종무
    • Journal of the Korean Ceramic Society
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    • v.31 no.2
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    • pp.206-212
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    • 1994
  • Effects of the film deposition process parameters on the properties such as deposition rate, etch rate, refractive index, stress and step coverage of plasma enhanced chemical vapor deposited (PECVD) tetraethylorthosilicate glass (TEOS) SiO2 film were investigated and analysed using SEM, FTIR and SIMS techniques. Increasing TEOS flow or decreasing O2 flow increased the deposition rate and the compressive stress of the oxide film but produced a less denser film. The deposition rate decreased owing to the decrease in the sticking coefficient of the TEOS and the O2 molecules onto the substrate Si with increasing the substrate temperature. Increasing the substrate temperature produced a denser film with a lower etch rate and the higher refractive index by lowering SiOH and moisture contents. Increasing the rf power increases the ion bombardment energy. This increase in energy, in turn, increases the deposition rate and tends to make the film denser. No appreciable changes were found in the deposition rate but the refractive index and the stress of the film decreased with increasing the deposition pressure. The carbon content in the plasma TEOS CVD oxide film prepared under our standard deposition conditions were very low according to the SIMS analysis results.

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Preparation of Buccal Patch Composed of Carbopol, Poloxamer and Hydroxypropyl Methylcellulose

  • Chun, Myung-Kwan;Kwak, Byoung-Tae;Choi, Hoo-Kyun
    • Archives of Pharmacal Research
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    • v.26 no.11
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    • pp.973-978
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    • 2003
  • A polymeric film composed of Carbopol, Poloxamer and hydroxypropyl methylcellulose was prepared to develop a buccal patch and the effects of composition of the film on adhesion time, swelling ratio, and dissolution of the film were studied. The effects of plasticizers or penetration enhancers on the release of triamcinolone acetonide (TAA) were also studied. The hydrogen bonding between Carbopol and Poloxamer played important role in reducing swelling ratio and dissolution rate of polymer film and increasing adhesion time. The swelling ratio of the composite film was significantly reduced and the adhesion time was increased when compared with Carbopol film. As the ratio of Poloxamer to hydroxypropyl methylcellulose increased from 0/66 to 33/33, the release rate of TAA decreased. However, no further significant decrease of release rate was observed beyond the ratio of 33/33. The release rate of TAA in the polymeric film containing polyethylene glycol 400, a plasticizer, showed the highest release rate followed by triethyl citrate, and castor oil. The release rate of TAA from the polymeric film containing permeation enhancers was slower than that from the control without enhancers. Therefore, these observations indicated that a preparation of a buccal patch is feasible with the polymeric film composed of Cabopol, Poloxamer and hydropropyl methylcellulose.

A Study on the Performance Characteristics of an Absorption Chiller for Variable Cooling Water Flow Rate at Partial Load Conditions (흡수식 냉온수기의 부분부하에 따른 냉각수 변유량시 성능특성에 관한 연구)

  • 박찬우;조현철;강용태
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.1
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    • pp.26-33
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    • 2004
  • In general, an absorption chiller or heat pump is operated under the constant cooling water flow rate condition even though the system works with a partial load. The objective of this paper is to study the effect of the cooling water flow rates and the temperature of cooling water on the system performance to find the energy saving methode for the partial load operation of the double effect $H_2O$/LiBr absorption chiller. It is found that the performance of the system is sensitive to the temperature of cooling water than the cooling water flow rate, so the decrease of the performance due to reducing the cooling water flow rate can be overcome with the reduction of the cooling water temperature by 1$^{\circ}C$. The flow rate of the cooling water flow rate ranges from 50% to 100% of the flow rate at normal conditions with a partial load. It is also found that the operation cost of the cooling water pump and the cooling tower can be reduced by 23%.

Experimental und Numerical Sensitivity Analyses on Push Pull Tracer Tests

  • Hwang, Hyeon-Tae;Lee, Gang-Geun
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.09a
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    • pp.312-316
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    • 2004
  • Single-well tracer tests, especially push pull tracer tests, are more effective to estimate hydraulic parameters and microbial metabolic activities in terms of duration and cost compared to multi-well tracer tests. However, there are some drawbacks in accuracy, complicated data analysis and uniqueness. These shortages are thought to be derived from the applied conditions which affect mass recovery curve and breakthrough curve. Factors such as extraction rate, resting period, hydraulic conductivity and hydraulic gradient are considered as the major factors determining the mass recovery rate and shape of the breakthrough curve. The results of the sensitivity analysis are summarized as follows: 1) the significant change in concentration of breakthrough curve is obtained when the extraction rate increases. This effect would also be much higher if the hydraulic conductivity is lower; 2) the mass recovery rate decreases with the increase of resting time, and the difference of mass recovery rates for different resting times is inversely proportional to the hydraulic conductivity; 3) the sensitivity values decrease with time. The hydraulic conductivity affects not only the early period, but the later period of the breakthrough curves; 4) The influence of the hydraulic gradient on the breakthrough curves is greater at earlier stage than at later stage. The mass recovery rate is inversely proportional to the hydraulic gradient.

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Characterization of SCR System for NOx Reduction of Diesel Engine (II) (디젤엔진의 질소산화물 저감을 위한 Urea SCR 시스템 특성 분석 (II))

  • Lee, Joon-Seong;Kim, Nam-Yong
    • Journal of the Korean Society for Precision Engineering
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    • v.25 no.11
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    • pp.83-89
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    • 2008
  • The Effect of Space Velocity(SV) on NOx conversion rate was performed to develop NOx reduction after-treatment system. SV is calculated from engine exhaust gas volume and SCR catalyst volume. Found the Urea injection duty of maximum efficiency for NOx conversion if increase SV, NOx Conversion rate is down. Especially, when SV is more than $110,000h^{-1}$, NOx conversion rate decrease suddenly. Same case, if SV is lower than $40,000h^{-1}$, NOx conversion rate is down. Also, the characterization of Urea-SCR system was performed. Three candidate injectors for injecting Urea were tested in terms of 속 injection rate and NOx reduction rate. The performances of SCR catalytic converter on temperature were investigated. The performance of Urea-SCR system was estimated in the NEDC test cycle with and without EGR. It was found that nozzle type injector had high NOx conversion rate. SCR catalytic converter had the highest efficiency at the temperature of $350^{\circ}C$. EGR+Urea-SCR system achieved NOx reduction efficiency of 73% through the NEDC test cycle.

Experimental Study on the Tribological Characteristics of Diluted Engine Oil by Diesel Fuel (디젤유가 혼입된 엔진오일의 트라이볼로지 특성에 관한 실험적 연구)

  • Kim, Han-Goo;Kim, Chung-Kyun
    • Tribology and Lubricants
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    • v.21 no.4
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    • pp.159-164
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    • 2005
  • An experimental study was conducted to evaluate characteristic variation of diluted engine oils in which contains diesel fuels and its tribological effects on engine components. In this study, diluted engine oils with $10\%,\;15\%,\;and\;20\%$ of initial fuel content rate have been used for measuring the viscosity reduction rate, blow-by gas increment rate, main gallery pressure reduction rate, and fuel content rate in engine oils. These parameters are strongly related to the tribological characteristics of key engine components. The kinematic viscosity of engine oils in which is contained by diesel fuels from $10\%\;to\;20\%$ in oils is decreasing to approximately $54\%$ of initial diluted fuel-oil volume ratios. The experimental results show that the distillated engine oil decrease the viscosity of engine oil and its oil film stiffness, and increase the wear rate of rubbing parts of engine components. Thus we recommend that the containing volume rate of fuels in engine oils should be restricted to $3\~4\%$ for a sophisticated Diesel engine and $5\~7\%$ for a standard one.

Changes of Rutin Content and Photosynthesis Rate of Korean Buckwheat Cultivars under Various Environmental Stresses

  • Yoon, Byeong-Sung;Kwun, Hyok-Oun;Shin, Sang-Eun;Jin, Cheng-Wu;Yu, Chang-Yeon;Cho, Dong-Ha
    • Korean Journal of Medicinal Crop Science
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    • v.11 no.4
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    • pp.284-288
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    • 2003
  • This study was conducted to classify photosynthesis rate and changes of rutin content of Korean buckwheat (cv. Chunchon-jaerae and Yangjeul-memil) treated with salinity, UV-C and low temperature. In case of cv. Chunchon-jaerae and Yangjeul-memil, according to the salt stress, transpiration rate, stomatal conductance and photosynthesis rate were decreased. Both cultivars also showed decrease of transpiration rate and photosynthesis rate under the UV-C. Rutin contents within leaf and stem of cv. Yangjeul-memil were decreased when NaCl concentration was high. Rutin contents within leaf and stem of cv. Yangjeul-memil were generally decreased when the time laps under the UV-C stress. Rutin contents within leaf and stem of cv. Chunchon-jaerae was also generally decreased when the time laps under the low temperature stress.

Fatigue Crack Growth Behavior of Austenite Stainless Steel in PWR Water Conditions (모사원전환경에서 오스테나이트 스테인리스강의 피로균열성장 평가)

  • Min, Ki-Deuk;Lee, Bong-Sang;Kim, Seon-Jin
    • Korean Journal of Materials Research
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    • v.25 no.4
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    • pp.183-190
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    • 2015
  • Fatigue crack growth rate tests were conducted as a function of temperature, dissolved hydrogen (DH) level, and frequency in a simulated PWR environment. Fatigue crack growth rates increased slightly with increasing temperature in air. However, the fatigue crack growth rate did not change with increasing temperature in PWR water conditions. The DH levels did not affect the measured crack growth rate under the given test conditions. At $316^{\circ}C$, oxides were observed on the fatigue crack surface, where the size of the oxide particles was about $0.2{\mu}m$ at 5 ppb. Fatigue crack growth rate increased slightly with decreasing frequency within the frequency range of 0.1 Hz and 10 Hz in PWR water conditions; however, crack growth rate increased considerably at 0.01 Hz. The decrease of the fatigue crack growth rate in PWR water condition is attributed to crack closure resulting from the formation of oxides near the crack tips at a rather fast loading frequency of 10 Hz.