• 제목/요약/키워드: Peak Flow

검색결과 1,468건 처리시간 0.033초

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
    • 천문학회보
    • /
    • 제39권2호
    • /
    • pp.88.2-88.2
    • /
    • 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.

  • PDF

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

  • 최종범
    • Journal of Chest Surgery
    • /
    • 제21권2호
    • /
    • pp.231-239
    • /
    • 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.

  • PDF

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

  • 임봉수;박윤해;김태응
    • 한국물환경학회지
    • /
    • 제31권4호
    • /
    • pp.428-435
    • /
    • 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%.

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

  • 안승섭
    • 한국농공학회지
    • /
    • 제42권3호
    • /
    • pp.76-88
    • /
    • 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.

  • PDF

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

  • 이정호
    • 한국산학기술학회논문지
    • /
    • 제11권12호
    • /
    • pp.5151-5156
    • /
    • 2010
  • 우수관망의 설계에 대한 기존의 연구들에서 관망의 노선은 최소의 건설비용을 목적으로 결정하게 되며, 기존의 연구들에서는 관망의 노선 변경에 따른 관거 내 흐름의 중첩효과는 관망 노선 결정에서 고려되지 않고 있다. 그러나 본 연구에서는 관망의 노선 결정에 있어서 관거 내 흐름의 변화를 고려하였으며, 관망 전체의 흐름을 제어 및 분산시킴으로써 내수침수 위험도를 감소시키고자 하였다. 이것은 관망 구성에 따른 관거 내 흐름의 중첩효과를 제어함으로써 가능하며, 이러한 흐름의 제어를 통하여 우수관망에서의 내수침수 위험도가 저감될 수 있다. 본 연구에서는 우수관망에서의 노선 결정에 따라서 달라지는 관거 내 흐름의 중첩효과와 그 결과로서 나타나는 유출구에서의 첨두 유출량 변화를 분석하였다. 관망의 노선 결정은 유전자알고리즘을 이용하였으며, 이때 목적함수는 유출구에서의 최소첨두유출량이 된다. 가상의 우수관망에 대하여 노선 결정에 따른 첨두유출량 변화를 분석한 결과 10년 빈도의 설계강우량에 대하여 강우지속시간 30분의 경우 관망 노선에 따른 최대 및 최소 첨두유출량 차이는 약 5.6%이며, 초과강우에 대한 내수침수 발생 분석을 위하여 2002년에 발생한 태풍 '루사'에 대한 적용 결과 월류량이 약 31% 감소되는 결과를 나타냈다.

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
    • /
    • 제19권3호
    • /
    • pp.296-301
    • /
    • 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.

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

  • 이삼철;정철현;이은숙;이해호;정영환;채혜진;최정아;이현철;오상부;손경현
    • 대한물리치료과학회지
    • /
    • 제18권3호
    • /
    • pp.9-16
    • /
    • 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.

  • PDF

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

  • 강상준
    • 환경정책연구
    • /
    • 제9권1호
    • /
    • pp.83-107
    • /
    • 2010
  • 본 연구의 목적은 빗물저류 및 흡수 등 우수관리를 위해 설치하는 최적관리기법(Best Management Practices: BMPs)의 효율적인 위치 및 분배 정도를 유역단위에서 살펴보는 것이다. 이를 위해 여러 개의 지류유역과 본류유역으로 이루어진 하나의 대유역을 구축한 후 Hydrological Simulation Program Fortran(HSPF)을 이용하여 도시유역 내다양한 규모와 위치의 BMPs 시나리오를 제작/모의하였다. 이때 대유역 내 전체 BMPs 면적은 일정하도록 하였으며, 유역하구의 첨두유량과 이와 관련된 회피비용을 효율성의 지표로 활용하였다. 모의 결과 BMPs가 상류지류 유역들에 분산 입지했을 때 가장 높은 효율을 보였으며, 본류유역을 포함하여 소유역 한 곳에 집중되었을 때 가장 낮은 효율을 보였다. 하지만 본 연구는 BMPs의 위치 및 분배 변수를 제외한 BMPs 설계 및 유지관리, 유역 내 다양한 토양특성등의 기타변수가 통제된 가상유역을 대상으로 진행되었다는 한계를 안고 있다. 따라서 본 연구는 유역관리에서 BMPs위치 및 분배가 유역관리에 중요한 정책변수일 수 있다는 가능성을 제시하는 데 그치고 있으며, 이러한 가능성은 향후 국내유역에 대한 실증적 모의연구를 통해 논의될 수 있을 것이다.

  • PDF

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

  • 강태욱;이상호
    • 한국수자원학회논문집
    • /
    • 제45권12호
    • /
    • pp.1213-1226
    • /
    • 2012
  • 유역유출 모의 모형의 자동 보정에 주로 사용되는 진화계열의 알고리즘은 무제약 최적화 알고리즘이다. 이러한 진화계열 알고리즘에 제약조건을 반영하기 위해서는 제약조건을 다룰 수 있는 별도의 방법이 요구된다. 본 연구의 목적은 진화계열 알고리즘의 일종인 집합체 혼합진화 알고리즘에 벌칙함수를 적용하여 제약조건을 고려할 수 있도록 하는 것이다. 또한, 제약조건을 고려할 수 있는 집합체 혼합진화 알고리즘을 SWMM의 자동 보정 모듈에 적용하여 기존 자동 보정 모듈의 기능을 개선하는 것이다. 홍수유출 해석에서는 첨두유량과 관련된 지표가 중요하므로 첨두유량의 오차와 첨두유량 발생시간의 오차를 제어할 수 있는 제약조건을 구성하였다. 제약조건을 포함하여 구성된 자동 보정 모듈은 밀양댐 유역과 구로1 빗물펌프장 배수유역의 홍수유출 모의 모형에 대하여 적용되었다. 자동 보정의 결과는 제약조건의 포함 유무에 따른 결과를 비교하여제시되었다. 그 결과, 제약조건을 고려함에 따라 본래의 목적함수를 크게 위배하지 않으면서, 첨두유량과 첨두유량 발생시간의 오차가 크게 개선되었다. 또한, 검증을 통해서도 제약최적화를 통한 자동보정의 적절성이 검토되었다. 결론적으로 벌칙함수를 이용한 제약조건의 반영을 통해 자동 보정 모듈의 기능을 향상시킬 수 있었다.

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

  • 신동원;윤천석
    • 한국자동차공학회논문집
    • /
    • 제18권1호
    • /
    • pp.131-138
    • /
    • 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.