• Title/Summary/Keyword: Peak-flow

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Accretion Flow and Disparate Profiles of Raman Scattered O $VI{\lambda}{\lambda}1032$ and 1038 in the Symbiotic Star V1016 Cygni

  • Heo, Jeong-Eun;Lee, Hee-Won
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.2
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    • pp.88.2-88.2
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    • 2014
  • The symbiotic star V1016 Cygni shows the Raman scattered O VI features at $6825{\AA}$ and $7088{\AA}$. These are formed through inelastic scattering of O VI 1032, 1038 by atomic hydrogen. They exhibit characteristic double peak profiles with a stronger red peak, which is explained by the accretion flow around the white dwarf. In addition, the two Raman features have different profiles in such a way that the blue part of the Raman 7088 feature is relatively more suppressed than the Raman 6825 counterpart. We produced the Doppler maps of the two Raman features in order to trace the origin of the disparate profiles. We conclude that the profile difference is due to various O VI 1032 to O VI 1038 flux ratios in the accretion region. This is consistent with the picture where the slow stellar wind from the giant interacts with the accretion flow around the white dwarf.

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Effect of Topical Hypothermia on Myocardial Protection from Ischemia - Experimental study using isolated rat heart perfusion technique- (흰쥐의 적출된 작업성 심장에서 허혈성 심정지시 국소냉각법이 심근보호에 미치는 영향)

  • 최종범
    • Journal of Chest Surgery
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    • v.21 no.2
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    • pp.231-239
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    • 1988
  • Currently numerous methods are in use for myocardial hypothermia as a myocardial preservation modality for cardiac operation. During cardiac ischemia after crystalloid cardioplegia[4C GIK solution], topical cold saline[Group I, a=9], topical ice slush[Group II, n=9] and topical ice chip[Group III, a=10] have been compared for myocardial surface cooling in the isolated rat heart model of cardiopulmonary bypass. During postischemic period, hemodynamic functions[aortic flow, coronary flow, peak aortic pressure and heart rate], biochemical enzymatic activities and cellular injuries with electron microscope were evaluated in this isolated rat heart perfusion model. Postischemic aortic flow, cardiac output and peak aortic pressure in Group I and Group II recovered better than Group III.[p< 0.05] Postischemic creatine kinase and lactate dehydrogenase leakages in Group II and Group III increased more than Group l and postischemic mitochondrial swelling in Group III was more severe than Group I, and Group II.[p< 0.05] These results suggest that topical cold saline was the better method than topical ice slush or topical ice chip as a myocardial preservation modality in the isolated rat heart model of cardiopulmonary bypass.

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Improvements of Inflow Controller Installed in Storm Overflow Diverging Tank for CSOs Control (우수토실에 설치된 월류수 제어를 위한 유입유량조절장치의 개선효과)

  • Lim, Bong-Su;Park, Youn-Hae;Kim, Tae-Eung
    • Journal of Korean Society on Water Environment
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    • v.31 no.4
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    • pp.428-435
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    • 2015
  • This study was carried out to evaluate the performance of a inflow controller for the control of combined sewer overflows (CSOs). Because of the inflow controller could be adjusted manually by predicting the maximum amount of peak flow, the mechanical adjustment of this controller was higher than the existing fixed-type controller in field application. Standardizing the relationship between the flow and the clearance and angle of an inlet cover plate on the inflow conditions can selected to the optimum conditions for the on-site. It was concluded that BOD pollutant loading at the region in which inflow controller was installed had shown the removal efficiency rate of 42%.

Variation of Non-Point Source Pollution according to AMC Condition Using Probable Rainfall (확률강우량을 이용한 AMC 조건에 따른 비점원 오염량의 변화)

  • 안승섭
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42 no.3
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    • pp.76-88
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    • 2000
  • AGNPS model is applied in this study to analyze the changes of non-point source pollutant according to AMC condition using probable rainfall. Probable rainfall of H-dam area by Gumber's extreme value distribution is computed through frequency analysis for each return period. 35 coarse grids are subdivided into 134 find grids of finite differential network to analyze peak flow soil loss quantity and nutrients of study area and the modified CN estimation equation shows good result about rainfall events-peak flow relationship. And as the consequence of estimation of soil loss quantity for each rainfall event soil loss quantity shows 120%-170% of actual soil loss quantity Regression analysis for the observed and calculated values of flow T-P AMC has an important effect on nutrients concentration of outflow and it if found that the excessive fertilization under AMC III condition may cause eutrophication by nutrients because the range of increase of outflow concentration appears relatively high.

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A Change of Peak Outflows due to Decision of Flow Path in Storm Sewer Network (우수관망 노선 결정에 따른 첨두유출량 변화 분석)

  • Lee, Jung-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.12
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    • pp.5151-5156
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    • 2010
  • In the previous researches for storm sewer design, the flow paths in overall network were determined to minimize the construction cost and then, it was not considered the superposition effect of runoff hydrographs in the sewer pipes. However, in this research, the flow paths are determined considering the superposition effect to reduce the inundation risk by controlling and distributing the flows in the sewer pipes. This is accomplished by distributing the inflows that enter into each junction by changing the flow path in which pipes are connected between junctions. In this paper, the superposition effect and peak outflows at outlet were analyzed considering the changes of the flow paths in the sewer network. Then, the flow paths are determined using genetic algorithm and the objective function is to minimize the peak outflow at outlet. As the applied result for the sample sewer network, the difference between maximum and minimum peak outflows which are caused by the change of flow path was about 5.6% for the design rainfall event of 10 years frequency with 30 min. duration. Also, the typhoon 'Rusa' which occurred at 2002 was applied to verify the reduction of inundation risk for the excessive rainfall, and then, the amount of overflows was reduced to about 31%.

Comparison of Leukotriene Receptor Antagonist and Theophylline in Addition to Inhaled Corticosteroid in Adult Asthma: A Meta-Analysis

  • Fang, Huijuan;Wang, Jianmiao;Jin, Di;Cao, Yong;Xu, Yongjian;Xiong, Weining
    • Biomolecules & Therapeutics
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    • v.19 no.3
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    • pp.296-301
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    • 2011
  • This meta-analysis was performed to evaluate the difference of the therapeutic effi cacy and adverse effects of leukotriene receptor antagonist and theophylline added to inhaled corticosteroids in adult asthma. Databases were searched for studies published through Nov, 2010. Randomized-controlled trials containing inhaled corticosteroids plus leukotriene receptor antagonist and inhaled corticosteroids plus sustained-release theophylline for asthma therapy were selected. For each report, data were extracted to the outcomes analyzed: mean change in morning peak expiratory flow, mean change in evening peak expiratory flow, mean change in morning forced expiratory volume in 1 sec, mean change in daily short bete2-agonist use, asthma exacerbation and adverse effects. Four assessable trials including 182 asthmatic patients were identified. Inhaled corticosteroids plus leukotriene receptor antagonist was superior to inhaled corticosteroids plus theophylline therapy in improving morning peak expiratory flow in asthmatics (mean difference 19.08 [95% confidence interval 13.37-23.79] l/min, p<0.001) and morning forced expiratory volume in 1 sec in asthmatics (mean difference 0.09 [95% confidence interval 0.03-0.14] liter, p=0.001). In evening peak expiratory flow, daily short bete2-agonist use, asthma exacerbation and adverse effects, there was no significant difference between these two therapies (All p>0.05). Our meta-analysis showed that the combination of inhaled corticosteroids plus leukotriene receptor antagonist resulted in more improvement in both peak expiratory flow and forced expiratory volume in 1 sec in the morning than inhaled corticosteroids plus sustained-release theophylline in adult asthmatics. Further trials are necessary to evaluate the dominant effects of the former combination.

Changes of Respiratory Ability According to Respiratory Muscle Exercises for Smokers and Non-smokers in Their Twenties (20대 흡연자와 비흡연자의 호흡근 강화 운동에 따른 호흡능력의 변화)

  • Lee, Sam-Cheol;Jung, Chul-Hyun;Lee, Eun-Suk;Lee, Hae-Ho;Joung, Young-Hwan;Chae, Hye-Jin;Choi, Jung-A;Lee, Hyun-Chul;Oh, Sang-Boo;Son, Kyung-Hyun
    • Journal of Korean Physical Therapy Science
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    • v.18 no.3
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    • pp.9-16
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    • 2011
  • Background : Smoking reduces the ability of the lungs to function. In particular, smoking reduces the vital capacity of the lungs, which is the amount of air the lungs can take in. This reduction in vital capacity has several important health effects. Purpose : The purpose of this study, therefore was to examine the effects of the respiratory muscle exercise on peak expiratory flow and respiratory muscle strength. Methods : For an experimental research design, it was employed 20 young healthy subjects and these subjects were assigned into two groups; a smoking group(n=10) and an non-smoking group(n=10). All groups were participated in respiratory muscle exercises twice a week for 5 weeks in same condition. For comparison between before and after for post treatment, it was analysed as paired t-test and ANCOVA. Results : The result of this study were as follows; In the case of smoking group, there were significant differences, from $427.77{\pm}76.61$ l/min to $526.66{\pm}58.52$ l/min of peak respiratory flow, from $94.33{\pm}22.07$ kg to $102.16{\pm}21.60$ kg of abdominal muscle strength between the before and the after of respiratory muscle strength exercises. In the case of nonsmoking group, there were significant differences, from $449.54{\pm}77.47$ l/min to $553.18{\pm}61.32$ l/min of peak respiratory flow, from $93.41{\pm}19.21$ kg to $101.58{\pm}18.92$ kg of abdominal muscle strength between the before and the after of respiratory muscle strength exercises. Conclusion : These results were suggested that the peak respiratory flow and muscle strength were improved after respiratory muscle strength exercises.

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Impact of BMP Allocation on Discharge and Avoided Costs in an Urbanized Watershed (최적관리기법 위치분배에 의한 유역단위 하천유량과 회피비용 변화에 관한 연구)

  • Kang, Sang-Jun
    • Journal of Environmental Policy
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    • v.9 no.1
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    • pp.83-107
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    • 2010
  • Urbanized environments are constructed to estimate peak flow and cost savings in response to possible BMP allocation at a watershed scale. The main goal is to explore the proper allocation of sub-watershed level BMPs for peak flow attenuation at a watershed scale. Since several individual site scale BMPs work as a form of aggregated BMPs at a sub-watershed scale, it is a question as to how to properly allocate the sub-watershed level BMPs at a watershed scale. The Hydrological Simulation Program-FORTRAN (HSPF) is set up for a hypothetically urbanized watershed. A peak flow is determined to be the primary variable of interest and targeted to characterize the spatial distribution of aggregated BMPs. Construction cost of a regional pond forms the basis of the economic valuation. The results indicate that when total size of BMPs is constant in the entire watershed, (1) it is most effective to have aggregated BMPs in some upper sub-watersheds while the BMPs in either the mainstem sub-watershed or a single sub-watershed are the least effective choices for peak flow attenuation at a watershed scale; (2) savings exist between allocation differences and reduced peak flow increases cost savings. The largest saving is found in the strategy of aggregated BMPs in some upper sub-watersheds. These findings, however, call for follow-up site specific case studies revisiting the watershed scale impacts of BMP allocation. Then, it will be argued that location and extent of decentralization are considerable policy variables for an alternative stormwater management policy at a watershed scale.

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Application of a Penalty Function to Improve Performance of an Automatic Calibration for a Watershed Runoff Event Simulation Model (홍수유출 모형 자동 보정의 벌칙함수를 이용한 기능 향상 연구)

  • Kang, Taeuk;Lee, Sangho
    • Journal of Korea Water Resources Association
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    • v.45 no.12
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    • pp.1213-1226
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    • 2012
  • Evolutionary algorithms, which are frequently used in an automatic calibration of watershed runoff simulation models, are unconstrained optimization algorithms. An additional method is required to impose constraints on those algorithms. The purpose of the study is to modify the SCE-UA (shuffled complex evolution-University of Arizona) to impose constraints by a penalty function and to improve performance of the automatic calibration module of the SWMM (storm water management model) linked with the SCE-UA. As indicators related to peak flow are important in watershed runoff event simulation, error of peak flow and error of peak flow occurrence time are selected to set up constraints. The automatic calibration module including the constraints was applied to the Milyang Dam Basin and the Guro 1 Pumping Station Basin. The automatic calibration results were compared with the results calibrated by an automatic calibration without the constraints. Error of peak flow and error of peak flow occurrence time were greatly improved and the original objective function value is not highly violated in the automatic calibration including the constraints. The automatic calibration model with constraints was also verified, and the results was excellent. In conclusion, the performance of the automatic calibration module for watershed runoff event simulation was improved by application of the penalty function to impose constraints.

Study on Transient Analysis for Flow Characteristics in DPF (DPF의 유동특성에 관한 과도해석 연구)

  • Shin, Dong-Won;Yoon, Cheon-Seog
    • Transactions of the Korean Society of Automotive Engineers
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    • v.18 no.1
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    • pp.131-138
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    • 2010
  • Because real flow of engine exhaust is very hot and highly transient, it may cause thermal and inertial loads on catalyzed filters in DPF. Transient and detailed flow and thermal simulations are necessary in this field. To assess the importance of time dependent phenomena, typical cone-type configuration such as an underbody DPF is selected for steady and transient analysis. User defined functions of FLUENT by sinusoidal inlet velocities are written and integrated with main solver for realistic simulation. Also, 4-cylinder and 6-cylinder engines for 3,000 L class are considered for the dynamic exhaust effect of engine type. Key parameters to understanding of catalyst performance and durability issues such as flow uniformity index and peak velocity are investigated. Also, pressure drop for engine power are considered. From the simulation results for three different cases, proper approach is recommended.