• Title/Summary/Keyword: Degree of saturation

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A Study of Numerical Analysis on Wall Impinging Spray (벽면충돌분무에 관한 수치해석)

  • Yeom, Jeong-Kuk
    • Journal of Power System Engineering
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    • v.17 no.2
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    • pp.21-28
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    • 2013
  • Phenomenon of droplet impingement with high temperature wall needs to be investigated because atomization process of droplet and cooling process of the wall by the impingement are very important in industry, thus studies concerned with temperature of piston wall have been conducted in spray characteristics analysis of diesel engine. Hence, in this study, we defined $DT_{sat}(=T_w-T_{sat})$ superheat degree of the wall by difference between $T_w$ considering surface temperature of piston in the actual engine and $T_{sat}$ saturation temperature of the fuel and then investigated spray behavior of wall impinging with variance of the boiling process. In this study, in order to analyze wall impingement of droplet in accordance with difference of boiling condition, calculational conditions were set as $DT_{sat}=40K$(nucleate boiling), $DT_{sat}=140K$(transition boiling), and $DT_{sat}=240K$(film boiling). As a result, it can be found that fuel vapor increases and droplet mass decreases in the order of the nucleate boiling, transition boiling, and film boiling.

Dynamic Behavior of Unsaturated Decomposed Mudstone Soil (불포화 이암풍화토의 동적거동)

  • 배중선;이주상;김주철;이종규
    • Proceedings of the Korean Geotechical Society Conference
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    • 2001.03a
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    • pp.541-548
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    • 2001
  • The interest in the dynamic properties of soils has increased strongly because of earthquake, heavy traffic, and foundations undergo high amplitude of vibrations. Most of soils in Korean peninsula are composed of granite soils, especially the decomposed mudstone soils are widely spread in Pohang areas, Kyong-buk province. Therefore, it Is very important to investigate the dynamic properties of these types of soils. The most important soil parameters under dynamic loadings are shear modulus and material dampings. Furthermore, few definitive data exist that can evaluate the behavior of unsaturated decomposed mudstone soils under dynamic loading conditions. The investigations described in this paper is designed to identify the shear modulus and damping ratio due to a surface tension for the unsaturated decomposed mudstone soils ulder low and high strain amplitude, For this purpose, the resonant column test and the cyclic triaxial test were performed. Test results and data have shown that the optimum degree of saturation under low and strain amplitude is 32 ∼ 37% which is higher than that of decomposed granite due to the amount of fine particles as well as the type and proportion of chief rock-forming minerals.

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Lipid Peroxidation and the Thiobarbituric Acid Assay: Standardization of the Assay When Using Saturated and Unsaturated Fatty Acids

  • Rael, Leonard T.;Thomas, Gregory W.;Craun, Michael L.;Curtis, C. Gerald;Bar-Or, Raphael;Bar-Or, David
    • BMB Reports
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    • v.37 no.6
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    • pp.749-752
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    • 2004
  • Saturated fatty acids are less vulnerable to lipid peroxidation than their unsaturated counterparts. In this investigation, individual fatty acids of the $C_{16}$, $C_{18}$ and $C_{20}$ families were subjected to the thiobarbituric (TBA) assay. These fatty acids were chosen based on their degree of saturation and configuration of double bonds. Interestingly, an assay threshold was reached where increasing the fatty acid concentration resulted in no additional decrease in the TBARS concentrations. Therefore, the linear range of TBARS inhibition was determined for fatty acids in the $C_{16}$ and $C_{20}$ families. The rate of TBARS inhibition was greater for the saturated than for unsaturated fatty acids, as measured from the slope of the linear range. These findings demonstrate the need to standardize the TBARS assay using multiple fatty acid concentrations when using this assay for measuring in vitro lipid peroxidation.

Degree of saturation of $(CaCO_3)$ in the East Sea (동해의 탄산칼슘$(CaCO_3)$ 포화도)

  • Kang, Dong-Jin;Kim, Kyung-Ryul;Lee, Kyung-Eun
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.6 no.4
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    • pp.234-241
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    • 2001
  • The degree of saturation of calcium carbonate in the East Sea was calculated from the data obtained from'99 expedition using R/V Roger Revelle. The calcium concentrations in seawaters were estimated from salinity data, and the carbonate ion concentrations were calculated from total alkalinity and pH data. The results suggest that the crossover from the supersaturation to undersaturation for calcium carbonate occur at the depth of approximately 200-400 m for calcite, and 100-300 m for aragonite. Compared to the Pacific and Atlantic oceans, these levels in the East Sea are shallow due to most likely lower temperature of sea water in this region.

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Characteristics of Electrokinetic Remediation of Unsaturated Soil I : Experimental Study (불포화토의 동전기 정화 특성 I : 실험적 연구)

  • Kim, Byung Il;Han, Sang Jae;Kim, Soo Sam
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.1C
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    • pp.1-8
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    • 2006
  • The purpose of this study is to experimentally analysis the eletrokinetic phenomena and remediation characteristics developed during the application of electrokinetic remediation technique to unsaturated soils contaminated by heavy metals. In the laboratory a series of column tests are performed on degree of saturation for shooting range soil. The test results indicated that Pb is mainly removed under unsaturated conditions by electromigration within diffuse double layer, and if the initial containment concentration is below cation exchange capacity and equals to adsorption per unit soil solid weight, the remedial efficiency decreases with the decreasing of transport efficiency due to the changes in the degree of saturation in the electric gradient of 1V/cm.

The Effects of Semi-Fowler's Position on Post-Operative Recovery in Recovery Room for Patients with Laparoscopic Abdominal Surgery (복강경 수술 후의 반좌위가 수술직후 회복정도에 미치는 영향)

  • Kim, Kyung Ah;Kim, Yeong Kyeong
    • Korean Journal of Adult Nursing
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    • v.16 no.4
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    • pp.566-574
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    • 2004
  • Purpose: To find the effects of semi-Fowler's position on the post-operative recovery for patients with laparoscopic abdominal surgery in recovery room. Method: The research was performed by nonequivalent control group non-synchronized quasi-experimental design. The subjects are forty patients who had laparoscopic abdominal surgery in a hospital from Aug. thru Nov. of 2003. Post-recovery scores and $O_2$saturation degree were measured. The experimental group was place in semi fowler's position while the control group was placed in supine position. The homogeneity between the control group and experimental group was analyzed using the Chi-square, and the hypothesis were tested using t-test. Result: 1. The patients in the experimental group placed in semi fowler's position showed significant higher post-recovery scores than those in the control group who were in a supine position. 2. The patients in the experimental group who were in semi Fowler's position showed no significant higher $O_2$ saturation degree than those in the control group who were in supine position. Conclusion: Based on the results described above, it is considered that the semi-Fowler's position might be effective in enhancing the post-operative recovery score of the patients with laparoscopic abdominal surgery in recovery room.

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LOS Analysis Frame for COSMOS at Isolated Intersections (실시간신호제어 독립교차로 서비스수준 분석 방법론)

  • Kim, Jin-Tae;Kim, Kang-Huy;Lee, Don-Ju
    • Journal of Korean Society of Transportation
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    • v.26 no.4
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    • pp.161-172
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    • 2008
  • The level of service (LOS) evaluation method of the Highway Capacity Manual (HCM) is limited to intersections with pre-timed signal operation, while advanced real-time traffic control systems have been expending in the field. This paper proposes a preliminary framework for LOS analysis at isolated intersections controlled by COSMOS, the real-time traffic control systems robustly utilizing the degree of saturation as basic inputs. The proposed LOS evaluation framework was devised with a pilot model developed to estimate the average cycle length and green times of COSMOS. The validation test showed that the proposed framework was able to accurately project the LOS, which was separately evaluated based upon field data.

불포화 토양내 유류성분의 포화도 평가를 위한 분배추적자의 활용 방안

  • Park Gi-Ho;Park Min-Ho;Sin Hang-Sik;Go Seok-O
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2006.04a
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    • pp.20-28
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    • 2006
  • Partitioning tracer tests were conducted to quantify the saturation degree of diesel and water in unsaturated soil, respectively. The use of partitioning tracers that partition into diesel, water, and air (i.e., three-phase partitioning), is in attractive alternative to traditional coring and analysis method. These gaseous partition tracers not global warming gas like CFC's are Butane, Acetylene, Ethylene, Methylene chloride, and Methane. The glass column packed with sandy soil was prepared, in which a three-phase system of air, water, and diesel was maintained. Conservative and partition gas tracers were injected into the columns and detected easily using a single GC detector(FID). For each tracer, a method of moments was used to estimate partition coefficient between water, diesel. and the air, respectively. The results from the column studies showed that the diesel/air tracer partition coefficient ranged from 8.2 to 868 and 9.2 for water/air. Saturation degree of diesel and water in the column, predicted by the partition coefficients obtained from tests, was underestimated up to 66% and 23% respectively.

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Applying the ANFIS to the Analysis of Rain and Dark Effects on the Saturation Headways at Signalized Intersections (강우 및 밝기에 따른 신호교차로 포화차두시간 분석에의 적응 뉴로-퍼지 적용)

  • Kim, Kyung Whan;Chung, Jae Whan;Kim, Daehyon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.4D
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    • pp.573-580
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    • 2006
  • The Saturation headway is a major parameter in estimating the intersection capacity and setting the signal timing. But Existing algorithms are still far from being robust in dealing with factors related to the variation of saturation headways at signalized intersections. So this study apply the fuzzy inference system using ANFIS. The ANFIS provides a method for the fuzzy modeling procedure to learn information about a data set, in order to compute the membership function parameters that best allow the associated fuzzy inference system to track the given input/output data. The climate conditions and the degree of brightness were chosen as the input variables when the rate of heavy vehicles is 10-25 %. These factors have the uncertain nature in quantification, which is the reason why these are chosen as the fuzzy variables. A neuro-fuzzy inference model to estimate saturation headways at signalized intersections was constructed in this study. Evaluating the model using the statistics of $R^2$, MAE and MSE, it was shown that the explainability of the model was very high, the values of the statistics being 0.993, 0.0289, 0.0173 respectively.

Effect of Saturation on Resilient Modulus of Cohesive soils as subgrade (점성토의 회복탄성계수($M_r$)에 대한 포화도의 영향)

  • Kim, Dong-Gyou;Croft, Frank M.
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.1140-1147
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    • 2005
  • The objective of this study was to identify the effect of the degree of saturation on the resilient modulus of cohesive soils as subgrade. Six representative cohesive soils representing A-4, A-6, and A-7-6 soil types collected from road construction sites across Ohio, were tested in the laboratory to determine their basic engineering properties. Resilient modulus tests were conducted on unsaturated cohesive soils at optimum moisture content, and samples compacted to optimum conditions but allowed to fully saturate. The subgrade compacted at optimum moisture content may be fully saturated due to seasonal change. Laboratory tests on fully saturated cohesive soils showed that the resilient modulus of saturated soils decreased to less than half that of soil specimens tested at optimum moisture content. The reduction of resilient modulus would possibly be caused by the buildup of pore water pressure. In resilient modulus testing performed in this study on saturated samples, pore water pressure increases were observed. Pore water pressure and residual pore water pressure gradually increased with an increase in deviator stress.

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