• Title/Summary/Keyword: Confidence-Flow

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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.

A Study on the Implementation of Air flow Control System using Profibus and Inverter (Profibus와 인버터를 이용한 공기량 제어시스템 구현)

  • 문용선;이명복;김동권;정철호
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.10
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    • pp.808-815
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    • 2003
  • Fieldbus technology is having a massive impact on the development of faster, smarter and less expensive industrial networking systems. However, there have been a few of practically applied cases and channels for obtaining technical advices. Moreover, the users in the industry don't trust the Fieldbus technology like they didn't trust PLC control system in 1970s. Therefore, in this paper, Air flow control system is constructed by Fieldbus technologies, Profibus and Inverter that controls the motor speed. With the features of the motor control, the amount of electric power consumption by the speed control of motor is measured by the constructed control system. From this measured result, the effectiveness of the airflow control system and Feasibility to the practical industry field is demonstrated To improve the confidence of Fieldbus technology, practically embodied cases and technical methods are presented.

Numerical analysis on the starting processes of the unsteady flow field in the Ludwieg tube with a quiet nozzle

  • Shen, Junmou;Lin, Jian;Gong, Jian;Li, Ruiqu
    • International Journal of Aerospace System Engineering
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    • v.2 no.2
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    • pp.62-66
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    • 2015
  • The starting processes of the Ludwieg tube hypersonic quiet tunnel plays very important role in the achievement of the quiet flow in the test section, which could affect the confidence coefficient of the data in the hypersonic transition experimental investigations. Thus, numerical analysis on that processes could help to understanding the running mode of the Ludwieg tube quiet tunnel and the propagation principle of the expansion wave series. To verify our computational method, the same parameter of the BAM6QT (the Boeing/AFOSR Mach-6 quiet tunnel at Purdue University) is used to compute, and it is agrees with our computational results.

Performance evaluation study of a commercially available smart patient-controlled analgesia pump with the microbalance method and an infusion analyzer

  • Park, Jinsoo;Jung, Bongsu
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.22 no.2
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    • pp.129-143
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    • 2022
  • Background: Patient-controlled analgesia (PCA) has been widely used as an effective medical treatment for pain and for postoperative analgesia. However, improper dose errors in intravenous (IV) administration of narcotic analgesics from a PCA infusion pump can cause patient harm. Furthermore, opioid overdose is considered one of the highest risk factors for patients receiving pain medications. Therefore, accurate delivery of opioid analgesics is a critical function of PCA infusion pumps. Methods: We designed a microbalance method that consisted of a closed acrylic chamber containing a layer and an oil layer with an electronic balance. A commercially available infusion analyzer (IDA-5, Fluke Co., Everett, WA, USA) was used to measure the accuracy of the infusion flow rate from a commercially available smart PCA infusion pump (PS-1000, UNIMEDICS, Co., Ltd., Seoul, Korea) and compared with the results of the microbalance method. We evaluated the uncertainty of the flow rate measurement using the ISO guide (GUM:1995 part3). The battery life, delay time of the occlusion alarm, and bolus function of the PCA pump were also tested. Results: The microbalance method was good in the short-term 2 h measurement, and IDA-5 was good in the long-term 24 h measurement. The two measurement systems can complement each other in the case of the measurement time. Regarding battery performance, PS-1000 lasted approximately 5 days in a 1 ml/hr flow rate condition without recharging the battery. The occlusion pressure alarm delays of PS-1000 satisfied the conventional alarm threshold of occlusion pressure (300-800 mmHg). Average accuracy bolus volume was measured as 63%, 95%, and 98.5% with 0.1 ml, 1 ml, and 2 ml bolus volume presets, respectively. A 1 ml/hr flow rate measurement was evaluated as 2.08% of expanded uncertainty, with a 95% confidence level. Conclusion: PS-1000 showed a flow accuracy to be within the infusion pump standard, which is ± 5% of flow accuracy. Occlusion alarm of PS-1000 was quickly transmitted, resulting in better safety for patients receiving IV infusion of opioids. PS-1000 is sufficient for a portable smart PCA infusion pump.

A Study on the Acute Effects of Fine Particles on Pulmonary Function of Schoolchildren in Inner-Mongolia, China

  • Kim, Dae-Seon;Yu, Seung-Do;Ahn, Seung-Chul;Na, Jin-Gyun
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2005.06a
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    • pp.311-314
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    • 2005
  • To evaluate the acute effects of fine particles on pulmonary function, a longitudinal study was conducted. This study was carried out for the schoolchildren(3rd and 4th grades) living in Inner-Mongolia, China. 113 Chinese children were asked to record their daily levels of peak expiratory flow rate(PEPR) using portable peak flow meter(mini-Wright) for 40 days and 3 time everyday(12 April 2004 to 21 May 2004). The atmospheric concentration of fine particles in study area was also determined everyday during same period. The relationship between dailypeak expiratory flow rate(PEFR) and fine particle levels was analyzed using a mixed linear regression models including gender, age, height, the presence of respiratory symptoms, and daily average relative humidity as extraneous variables. The analysis showed that the increase of fine particle concentrations was negatively associated with the variability in PEPR. The IQR(inter-quartile range) increments of $PM_{10}$ or $PM_{2.5}(66.0{\mu}g/m^3$ and $118.9{\mu}g/m^3$, respectively) were also shown to be related with 1.422L/min(95% Confidence intervals: 0.270 ${\sim}$ 2.574) and 1.214L1min(95% Cl: 0.010 ${\sim}$ 2.418) decline in PEFR.

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Verification Test and Model Updating for a Nuclear Fuel Rod with Its Supporting Structure

  • H. S. Kang;K. N. Song;Kim, H. K.;K. H. Yoon;Y. H. Jung
    • Nuclear Engineering and Technology
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    • v.33 no.1
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    • pp.73-82
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    • 2001
  • Pressurized water reactor(PWR) fuel rods. which are continuously supported by a spring system called a spacer grid(SG), are exposed to reactor coolant at a flow velocity of up to 6-8 m/s. It is known that the vibration of 3 fuel rod is generated by the coolant flow, a so-called flow-induced-vibration(FIV), and the relative motion induced by the FIV between the fuel rod and the SG can wear away the surface of the fuel rod, which occasionally leads to its fretting failure. It is, therefore, important to understand the vibration characteristics of the fuel rod and reflect that in its design. In this paper, vibration analyses of the fuel rod with two different SGs were performed using both analytical and experimental methods. Updating of the finite element(FE) model using the measured data was performed in order to enhance confidence in the FE model of fuel rods supported by an SG. It was found that the modal parameters are very sensitive to the spring constant of the SG.

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Validation of RANS models and Large Eddy simulation for predicting crossflow induced by mixing vanes in rod bundle

  • Wiltschko, Fabian;Qu, Wenhai;Xiong, Jinbiao
    • Nuclear Engineering and Technology
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    • v.53 no.11
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    • pp.3625-3634
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    • 2021
  • The crossflow is the key phenomenon in turbulent flow inside rod bundles. In order to establish confidence on application of computational fluid dynamics (CFD) to simulate the crossflow in rod bundles, three Reynolds-Averaged Navier Stokes (RANS) models i.e. the realizable k-ε model, the k-ω SST model and the Reynolds stress model (RSM), and the Large Eddy simulations (LES) with the Wall-Adapting Local Eddy-viscosity (WALE) model are validated based on the Particle Image Velocimetry (PIV) flow measurement experiment in a 5 × 5 rod bundle. In order to investigate effects of periodic boundary condition in the gap, the numerical results obtained with four inner subchannels are compared with that obtained with the whole 5 × 5 rod bundle. The results show that periodic boundaries in the gaps produce strong errors far downstream of the spacer grid, and therefore the full 5 × 5 rod bundle should be simulated. Furthermore, it can be concluded, that the realizable k-ε model can only provide reasonable results very close to the spacer grid, while the other investigated models are in good agreement with the experimental data in the whole downstream flow in the rod bundle. The LES approach shows superiority to the RANS models.

A Study on a Solution For Growth of Beauty Salon Franchise - around an influence of a conflict upon a solidarity -

  • Lee, Joung-Ho;Chun, Tae-Yoo
    • International Journal of Costume and Fashion
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    • v.3
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    • pp.121-139
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    • 2003
  • A purpose of this study is to measure degree of solidarity and conflict of the beauty salon franchisees according to an influence strategy of franchiser and grasp characteristics revealed from managing a franchise system. This will also contribute to improving results of franchise systems and considering a direction for development. This study examined existing studies relevant with conflict and solidarity and analysed relativity between relevant variables and grasped the flow of studies and then set hypotheses in order to present a device for decreasing conflict within a franchise system of beauty shops and for increasing a solidarity and subsequently analysed samples and tested data. The data for this study are researched by sending questionnaires to beauty salons which participated in one of franchise systems and they are analyzed by various methods in a statistics. After studying some relevant theories, this study used the definition of the franchise system in beauty salons as an entity of a political-economy paradigm. A franchiser desires to influence member shops with an influence-strategy. Therefore member shops which perceived it go through a conflict and then such a process is revealed as making significant influence on solidarity. Beauty salon franchise exists by reciprocal confidence and transaction. If an opportunism gain in influence owing to an conflict intensification, there would be no steady formation of relationship. Therefore the head office should develop a member-shop-management-system by more scientific and more technical methods and prevent, in advance, member stores from seeking for negative opportunism.

The Comparison of Grid Resolutions using EFDC in Saemangeum Reservoir (격자 해상도에 따른 EFDC의 새만금호 모의)

  • Shin, Yu-Ri;Jang, Jeongryeil;Choi, Jung-Hoon;Cho, Young Kweon
    • Journal of Korean Society on Water Environment
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    • v.28 no.5
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    • pp.646-656
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    • 2012
  • This study area was Saemangeum Reservoir in Korea and the applied model was Environmental Fluid Dynamics Code(EFDC). It was the same as the scenarios to the boundary and initial conditions except the resolutions of the model grids. The resolutions were about 800 and 2,000 cells. It was considered scenario 1 and 2. The model was performed to simulate the water temperature, salinity, water quality parameters such as dissolved oxygen(DO), chemical oxygen demand(COD), total nitrogen(T-N), and total phosphorus(T-P) at 2008. The simulation results of the two scenarios were reflected in the trend of observed data tolerably. However, water flow, water temperature, and salinity showed high confidence level at the scenario 1. The water quality items did not present high confidence level at the scenario 1 because which concept was considered to biochemical and physical processes. This result shows that grid resolution has an influence on the water transport and the effect is reflected directly shallow and narrow water area. But, the selection of grid resolution should be considered the purpose of model simulation and the process of target items.

Derivation of Optimal Design Flood by Gamma and Generalized Gamma Distribution Models(I) - On the Gamma Distribution Models - (Gamma 및 Generalized Gamma 분포 모형에 의한 적정 설계홍수량의 유도 (I) -Gamma 분포 모형을 중심으로-)

  • 이순혁;박명근;정연수;맹승진;류경식
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.39 no.3
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    • pp.83-95
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    • 1997
  • This study was conducted to derive optimal design floods by Gamma distribution models of the annual maximum series at eight watersheds along Geum , Yeong San and Seom Jin river Systems, Design floods obtained by different methods for evaluation of parameters and for plotting positions in the Gamma distribution models were compared by the relative mean errors and graphical fit along with 95% confidence interval plotted on Gamma probability paper. The results were analyzed and summarized as follows. 1.Adequacy for the analysis of flood flow data used in this study was confirmed by the tests of Independence, Homogeneity and detection of Outliers. 2.Basic statistics and parameters were calculated by Gamma distribution models using Methods of Moments and Maximum Likelihood. 3.It was found that design floods derived by the method of maximum likelihood and Hazen plotting position formular of two parameter Gamma distribution are much closer to those of the observed data in comparison with those obtained by other methods for parameters and for plotting positions from the viewpoint of relative mean errors. 4.Reliability of derived design floods by both maximum likelihood and method of moments with two parameter Gamma distribution was acknowledged within 95% confidence interval.

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