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Evaluation of the Impact of Refined Quality Control Management Model on the Qualified Rate of Disinfection and Sterilization of Surgical Instruments in the Sterilization Supply Center 被引量:1
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作者 Qin Liu 《Journal of Clinical and Nursing Research》 2024年第1期168-173,共6页
Objective:To evaluate the application value of a refined quality control management model for a sterilization supply center.Methods:A retrospective analysis was conducted on the work situation of the sterilization sup... Objective:To evaluate the application value of a refined quality control management model for a sterilization supply center.Methods:A retrospective analysis was conducted on the work situation of the sterilization supply center from January 2021 to January 2023.The work situation before January 31,2022,was classified as the control group;a routine quality control management model was implemented,and the work situation after January 31,2022,was classified as the observation group.The quality of medical device management and department satisfaction between the two groups were compared.Results:The timely recovery and supply rate,classification and cleaning pass rate,disinfection pass rate,packaging pass rate,sterilization pass rate,and department satisfaction score in the observation group were all higher than those of the control group(P<0.05).Conclusion:Implementing a refined quality control management model in the sterilization supply center can improve the quality management level of medical devices and department satisfaction and is worthy of promotion. 展开更多
关键词 Refined quality control management model Sterilization supply center Disinfection and sterilization pass rate
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Reducing the Error Rate of Drug Delivery in Hospital Pharmacies: From the Angle of Pharmacy Quality Control Circle 被引量:1
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作者 Wang Shuling Chen Hui +1 位作者 De Xianhui Liu Linchuan 《Asian Journal of Social Pharmacy》 2019年第2期66-76,共11页
Objective To explore the effect of applying pharmacy quality control circle to reduce the error rate of drug delivery in inpatient pharmacy,and to improve the service quality of inpatient pharmacy staff.Methods Accord... Objective To explore the effect of applying pharmacy quality control circle to reduce the error rate of drug delivery in inpatient pharmacy,and to improve the service quality of inpatient pharmacy staff.Methods According to the ten standardized steps of pharmaceutical product management and Gantt chart,fishbone diagram and Plato were used to analyze the causes of drug delivery errors in hospital pharmacies,to find countermeasures and confirm the implementation effect.Results and Conclusion The error rate was reduced from 52% before implementation to 27.8%,and the target achievement rate was 100%.The staff’s understanding and application ability of pharmaceutical product circle was further enhanced.The “Training Standard for Newcomers” has reference value for hospital inpatient pharmacies and it can be promoted continuously.Pharmaceutical quality control circle can improve the quality of pharmacy services in hospitals. 展开更多
关键词 quality control circle INPATIENT PHARMACY DRUG ERROR rate
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Reducing the Internal Difference Error Rate in Hospital Pharmacies:From the Angle of Quality Control Circle 被引量:1
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作者 Wang Shuling Lei Yingzi +2 位作者 Liu Linchuan Wang Ruili He Yalan 《Asian Journal of Social Pharmacy》 2020年第2期73-82,共10页
Objective To improve the management level of pharmacy dispensing center,reduce dispensing errors and promote the safety of drug use.Methods Hospital pharmacies could be managed according to the theory of quality contr... Objective To improve the management level of pharmacy dispensing center,reduce dispensing errors and promote the safety of drug use.Methods Hospital pharmacies could be managed according to the theory of quality control circle(QCC).Based on the ten steps of QCC,the internal difference error rate in pharmacies could be reduced.Results and Conclusion The error rate of pharmacies was reduced from 2.74‰to 0.57‰,and the goal achievement rate was 108.466.Besides,the progress rate reached 84.82%.The abilities of circle members were improved,and the operation of pharmacy was more standardized.The activity of QCC is helpful to reduce the internal difference error rate,improve the operation level of pharmacy and ensure the safety of drug use. 展开更多
关键词 quality control circle(QCC) medical institution internal difference error rate
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Effects of retrospective quality control on pressure-flow data with computer-based urodynamic systems from men with benign prostatic hyperplasia 被引量:2
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作者 Li-Min Liao Werner Schaefer 《Asian Journal of Andrology》 SCIE CAS CSCD 2007年第6期771-780,共10页
Aim: To evaluate the effects of retrospective quality control on pressure-flow data with computer-based urodynamic systems from men with benign prostatic hyperplasia (BPH). Methods: A total of 582 traces of pressu... Aim: To evaluate the effects of retrospective quality control on pressure-flow data with computer-based urodynamic systems from men with benign prostatic hyperplasia (BPH). Methods: A total of 582 traces of pressure-flow study from 181 men with BPH was included in the study. For each trace, maximum urinary flow rate (Qmax) and detrusor pressure at Qmax (pdet.Qmax) were, respectively, read from manually smoothed and corrected uroflow and detrusor pressure curves from the computer print-outs. Obstruction coefficient, International Continence Society (ICS) and Schaefer nomograms were used to detect urethral resistance and to diagnose obstruction. The results obtained by manual reading were compared with those from computer-based systems. Results: After manual correction, Qmax underwent a consistently significant decrease by 1.2 mL/s on average (P 〈 0.001), and had a change range of 0.5-10.4 mL/s. However, pdet.Qmax underwent inconsistently intra-individual changes after correction. The obstruction coefficient increased significantly, by an average of 0.07 (P 〈 0.05). Using the ICS nomogram, the percentage of obstruction increased from 69.8% to 73.9%, and of the non-obstruction decreased from 8.8% to 5.3% (P 〈 0.05). There were 11% of traces that changed the classifications using the ICS nomogram, and 28.9% that changed the grades for the Schaefer nomogram. Conclusion: Systematically significant differences in parameters from pres- sure-flow study between manual readings and computer recordings were demonstrated. Manual correction resulted in a consistently lower Q a higher urethral resistance, and an aggravating obstruction. Manual readings can correct considerable false diagnoses for obstruction. Retrospective quality control of pressure-flow data with com- puter-based systems is necessary. 展开更多
关键词 benign prostatic hyperplasia pressure-flow study quality control
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Improvement of uniformity in cultivation environment and crop growth rate by hybrid control of air flow devices
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作者 BAEK Min-Seon KWON Sook-Youn LIM Jae-Hyun 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4702-4708,共7页
A complete control type plant factory has high efficiency in terms of cultivation area by constructing vertical multiple layered cultivation beds.However,it has a problem of irregular crop growth due to temperature de... A complete control type plant factory has high efficiency in terms of cultivation area by constructing vertical multiple layered cultivation beds.However,it has a problem of irregular crop growth due to temperature deviation at upper and lower beds and increases in energy consumption by a prolonged cultivation period.In this work,air flow rate inside a facility was improved by a hybrid control of air flow devices like air conditioning and air circulation fan with an established wireless sensor network to minimize temperature deviations between upper and lower beds and to promote crop growth.The performance of proposed system was verified with an experimental environment or Case A wherein air conditioning device was operated without a control algorithm and Case B wherein air conditioning and circulation fans were alternatively operated based on the hybrid control algorithm.After planting leafy vegetables under each experimental condition,crops were cultivated for 21 days.As a result,Case B wherein AC(air conditioning) and ACF(air-circulation fan) were alternatively operated based on the hybrid control algorithm showed that fresh mass,number of leaves,and leaf length for the crops grown were increased by 40.6%,41.1%,and 11.1%,respectively,compared to Case A. 展开更多
关键词 air flow devices hybrid control cultivation environment UNIFORMITY growth rate
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Branch Quality Control of Gas-Liquid Two-Phase Flow Using a Novel T-Junction Type Distributor
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作者 Fa-Chun Liang Jing Chen +1 位作者 Jin-Long Wang Hao Yu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第4期110-115,共6页
In order to eliminate mal-distribution and ensure the side arm to produce desirable gas quality a special distributor is proposed. The experimental distributor mainly consists of a straight through section,a gas extra... In order to eliminate mal-distribution and ensure the side arm to produce desirable gas quality a special distributor is proposed. The experimental distributor mainly consists of a straight through section,a gas extraction line,a liquid extraction line and a side arm branch. A gas orifice and a liquid orifice are mounted at the gas and liquid extraction line respectively to control the outlet gas quality. The diameter of the liquid orifice was set to 2. 50 mm and three gas orifices with different size( dG= 2. 65,5. 00,10. 00 mm) were tested. The experiments were carried out at an air-water two-phase flow loop. The gas superficial velocity ranged from 6. 0 to 20. 0 m /s and the liquid superficial velocity was in the range of 0. 02- 0. 18 m /s. Flow patterns such as wave flow,slug flow and annular flow were observed. The gas quality of the side arm branch was found mainly determined by the flow area ratio of the gas orifice to the liquid orifice and independent of gas and liquid superficial velocity,flow patterns and extraction flux. 展开更多
关键词 gas-liquid two-phase flow DISTRIBUTOR phase splitting flow pattern quality control
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Validation and quality control of hematolymphoid neoplasm immunophenotyping by flow cytometry
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作者 Wu Lijuan Xu Dongsheng 《国际检验医学杂志》 CAS 2012年第23期2852-2858,共7页
cytometric immunophenotyping has evolved from two-parameter quantitative measurement of peripheral blood lymphocytes to five-or more parameter qualitative evaluation of bone marrow for hematopathology.Leukemia/lymphom... cytometric immunophenotyping has evolved from two-parameter quantitative measurement of peripheral blood lymphocytes to five-or more parameter qualitative evaluation of bone marrow for hematopathology.Leukemia/lymphoma immunophenotyping represent an important addition to histomorphology in the diagnosis,classification and monitoring of hematolymphoid neoplasms.The complexity of five-or more parameter analyses and the interpretation of the data rely on standardization and validation of the instrument,the reagent and the procedure.In addition,clinical flow cytometry laboratories in U.S.are required to document proficiency testing,sample preparation,method accuracy,specificity,sensitivity and precision.CLSI and the U.S.-Canadian Consensus Conference have provided recommendations,but each laboratory is responsible for validating its own qualitative and quantitative procedures.This paper introduces the procedures for quality control of all levels of the operation in a clinical flow cytometry laboratory in USA. 展开更多
关键词 英文摘要 编辑工作 学术论文 期刊
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Graft Quality Control with the Traditional Roller Pump Flow Measurement in Comparison to the Transit-Time Flow Measurement
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作者 Hannan Dalyanoglu Hiroyuki Kamiya +4 位作者 Mohammed Kurt Marc Thone Payam Akhyari Artur Lichtenberg Bernhard Korbmacher 《Open Journal of Thoracic Surgery》 2011年第2期9-11,共3页
Objective: Vein graft quality control had been traditionally done for more than 20 years with a roller-pump flow measurement (RPFM) in our institute until off-pump coronary artery bypass grafting was introduced as the... Objective: Vein graft quality control had been traditionally done for more than 20 years with a roller-pump flow measurement (RPFM) in our institute until off-pump coronary artery bypass grafting was introduced as the standard technique of myocardial revascularization in the year 2009 in our institute. In this study, the RPFM method was compared with the Transit-time flow measurement (TTFM). Patients and Methods: From February to September 2005, 31 patients (5 females) undergoing CABG in our institute were included into the study. All the patients were operated with cardiopulmonary bypass. In those patients, 27 distal anastomoses were done with the left internal thoracic artery and 99 anastomoses were done with vein grafts. Those 99 vein graft were assessed both, with the RPFM method and TTFM method. Results: CABG could be safely performed in all cases. In all target vessels, the RPFM method overestimated bypass flow compared to the TTFM method, and simple linear regression revealed no correlation between the TTFM measurement and the RPFM measurement (r = 0.08, p = 0.21). There were two cases in which a graft problem could be detected only with TTFM method, even in our small patient cohort. Conclusion: The present study suggests that the TTFM method is clearly superior to the traditional RPFM method and we believe now that TTFM should be performed routinely in all CABG to improve patient care and quality of surgical results. 展开更多
关键词 Coronary Artery Bypass Grafting flow Measurement quality control
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Operational guidance for aeration and flow augmentation for the Chicago Area Waterway System—A case study
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作者 Charles S.Melching Jennifer Wasik +1 位作者 Ed Staudacher Thomas Minarik 《Water Science and Engineering》 EI CAS CSCD 2023年第4期345-358,共14页
The Chicago Area Waterway System(CAWS)is a 133.9 km branching network of navigable waterways controlled by hydraulic structures,in which the majority of the flow is treated wastewater effluent and there are periods of... The Chicago Area Waterway System(CAWS)is a 133.9 km branching network of navigable waterways controlled by hydraulic structures,in which the majority of the flow is treated wastewater effluent and there are periods of substantial combined sewer overflows.The CAWS comprises a network of effluent dominated streams.More stringent dissolved oxygen(DO)standards and a reduced flow augmentation allowance have been recently applied to the CAWS.Therefore,a carefully calibrated and verified one-dimensional flow and water quality model was applied to the CAWS to determine emission-based real-time control guidelines for the operation of flow augmentation and aeration stations.The goal of these guidelines was to attain DO standards at least 95%of the time.The“optimal”guidelines were tested for representative normal,dry,and wet years.The finally proposed guidelines were found in the simulations to attain the 95%target for nearly all locations in the CAWS for the three test years.The developed operational guidelines have been applied since 2018 and have shown improved attainment of the DO standards throughout the CAWS while at the same time achieving similar energy use at the aeration stations on the Calumet River system,greatly lowered energy use on the Chicago River system,and greatly lowered discretionary diversion from Lake Michigan,meeting the recently enacted lower amount of allowed annual discretionary diversion.This case study indicates that emission-based real-time control developed from a well calibrated model holds potential to help many receiving water bodies achieve high attainment of water quality standards. 展开更多
关键词 Water quality modeling Water quality management Real-time control Stream aeration flow augmentation Dissolved oxygen
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The Principle of Mathematical Induction Applied to the Generalized Model for the Economic Design of X-Control Charts 被引量:1
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作者 Mohamed E. Seliaman Salih O. Duffuaa 《Open Journal of Applied Sciences》 2012年第4期236-240,共5页
Rahim and Banerjee [1] developed a general model for the optimal design of x-control charts. The model minimizes the expected cost per unit time. The heart of the model is a theorem that derives the expected total cos... Rahim and Banerjee [1] developed a general model for the optimal design of x-control charts. The model minimizes the expected cost per unit time. The heart of the model is a theorem that derives the expected total cost and the expected cycle length. In this paper an alternative simple proof for the theorem is provided based on mathematical induction. 展开更多
关键词 Discrete MAtheMATICS MAtheMATICAL INDUCTION Statistical quality control Design of -control Charts HAZARD rate Function
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Intelligent Flow Control Technique of ABR Service in ATM Networks Based on Fuzzy Neural Networks 被引量:7
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作者 Zhang Liangjie Li Yanda Li Qinghua Wang Pu (Dept of Automation, Tsinghua University, Beijing 100084) 《通信学报》 EI CSCD 北大核心 1997年第3期3-9,共7页
InteligentFlowControlTechniqueofABRServiceinATMNetworksBasedonFuzzyNeuralNetworks①ZhangLiangjieLiYandaLiQing... InteligentFlowControlTechniqueofABRServiceinATMNetworksBasedonFuzzyNeuralNetworks①ZhangLiangjieLiYandaLiQinghuaWangPu(DeptofA... 展开更多
关键词 模糊神经网络 流量控制 异步传输网 反馈 可用位率
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A new method based on two freedom-degree PD-P flow rate controller for congestion control in computer networks
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作者 Shen Wei(沈伟) Feng Rui Shao Huihe 《High Technology Letters》 EI CAS 2005年第3期257-262,共6页
The rate-based feedback PD-P controller of two freedom-degrees is proposed for the congestion control in computer networks to improve the abilities against disturbance. Moreover, the Dahlin algorithm is used for setti... The rate-based feedback PD-P controller of two freedom-degrees is proposed for the congestion control in computer networks to improve the abilities against disturbance. Moreover, the Dahlin algorithm is used for setting the controller to overcome the adverse effect caused by the propagation delay effectively. The research results show that the proposed scheme not only can make sources respond to the changes of network state more quickly, but also has a good robustness against estimated error of the delay. Then the packet queue level in buffer will be stabilized on the set-point quickly, and the delay and its jitter of the packet queuing will also become smaller. Besides, the flexible bandwidth allotment can be obtained by setting the weight coefficients. 展开更多
关键词 computer networks flow rate control two freedom-degrees
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DOUBLE LOOP ACTIVE VIBRATION CONTROL OF PNEUMATIC ISOLATOR WITH TWO SEPARATE CHAMBERS
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作者 YANG Qingjun LI Jun WANG Zuwen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第4期610-613,共4页
A newly designed pneumatic spring with two separate chambers is promoted and double-loop active control is introduced to overcome the following drawbacks of passive pneumatic isolation: ① The low frequency resonance... A newly designed pneumatic spring with two separate chambers is promoted and double-loop active control is introduced to overcome the following drawbacks of passive pneumatic isolation: ① The low frequency resonances introduced into the system; ② Conflict between lower isolation frequency and stiffness high enough to limit quasi-static stroke;③ Inconsistent isolation level with different force load. The design of two separate chambers is for the purpose of tuning support frequency and force independently and each chamber is controlled by a different valve. The inner one of double-loop structure is pressure control, and in order to obtain good performance, nonlinearities compensation and motion flow rate compensation (MFRC) are added besides the basic cascade compensation, and the influence of tube length is studied. The outer loop has two functions: one is to eliminate the resonance caused by isolation support and to broaden the isolation frequency band by payload velocity feedback and base velocity feed forward, and the other is to tune support force and support stiffness simultaneously and independently, which means the support force will have no effect on support stiffness. Theoretical analysis and experiment results show that the three drawbacks are overcome simultaneously. 展开更多
关键词 Pneumatic isolator Active vibration control Double-loop control Two separate chambers Mass flow rate compensation (MFRC)
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Modeling and Control of Time-pressure Dispensing for Semiconductor Manufacturing 被引量:5
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作者 Cong-Ping Chen Han-Xiong Li Han Ding 《International Journal of Automation and computing》 EI 2007年第4期422-427,共6页
To improve the consistency of the adhesive amount dispensed by the time-pressure dispenser for semiconductor manufacturing, a non-Newtonian fluid flow rate model is developed to represent and estimate the adhesive amo... To improve the consistency of the adhesive amount dispensed by the time-pressure dispenser for semiconductor manufacturing, a non-Newtonian fluid flow rate model is developed to represent and estimate the adhesive amount dispensed in each cycle. Taking account of gas compressibility, an intelligent model-based control strategy is proposed to compensate the deviation of adhesive amount dispensed from the desired one. Both simulations and experiments show that the dispensing consistency is greatly improved by using the model-based control strategy developed in this paper. 展开更多
关键词 Time-pressure dispensing CONSISTENCY fluid flow rate model model-based control.
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Optimum control strategy for all-variable speed chiller plant 被引量:3
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作者 蒋小强 龙惟定 李敏 《Journal of Central South University》 SCIE EI CAS 2011年第2期573-579,共7页
The optimum control strategy and the saving potential of all variable chiller plant under the conditions of changing building cooling load and cooling water supply temperature were investigated. Based on a simulation ... The optimum control strategy and the saving potential of all variable chiller plant under the conditions of changing building cooling load and cooling water supply temperature were investigated. Based on a simulation model of water source chiller plant established in dynamic transient simulation program (TRNSYS),the four-variable quadratic orthogonal regression experiments were carried out by taking cooling load,cooling water supply temperature,cooling water flow rate and chilled water flow rate as variables,and the fitting formulas expressing the relationships between the total energy consumption of chiller plant with the four selected parameters was obtained. With the SAS statistical software and MATHEMATICA mathematical software,the optimal chilled water flow rate and cooling water flow rate which result in the minimum total energy consumption were determined under continuously varying cooling load and cooling water supply temperature. With regard to a chiller plant serving an office building in Shanghai,the total energy consumptions under different control strategies were computed in terms of the forecasting function of cooling load and water source temperature. The results show that applying the optimal control strategy to the chiller plant can bring a saving of 23.27% in power compared with the corresponding conventional variable speed plant,indicating that the optimal control strategy can improve the energy efficiency of chiller plant. 展开更多
关键词 chiller plant control strategy variable speed cooling water flow rate chilled water flow rate
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BUFFER DIMENSIONING FOR RATE-BASED CONTROL IN ATM NETWORK
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作者 唐俊华 顾尚杰 诸鸿文 《Journal of Shanghai Jiaotong university(Science)》 EI 1997年第2期80-85,共6页
Available Bit Rate (ABR) service has been developed to support data applications to asynchronous transfer mode (ATM) networks.Since a ratebased feedback flow control mechanism has been selected as a standard by ATM Fo... Available Bit Rate (ABR) service has been developed to support data applications to asynchronous transfer mode (ATM) networks.Since a ratebased feedback flow control mechanism has been selected as a standard by ATM Forum,buffering becomes an issue that needs intensive study.In this paper,the queuing performance in a switch is studied in detail.It is theoretically proven that the goals of no cell loss and full utilization of link capacity can be achieved by choosing an appropriate buffersize and threshold of the switch buffer which is supported by our simulation results of a complex network. 展开更多
关键词 ATM (asynchronous transfer mode) ABR(available bit rate) BUFFERING flow control
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Pressure control of PEMFC distributed power generator
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作者 张颖颖 曹广益 朱新坚 《Journal of Shanghai University(English Edition)》 CAS 2006年第3期262-267,共6页
Control design is important for PEMFC (proton exchange membrane fuel cell) distributed power generator to satisfy user requirement for safe and stable operation. For a complex multi-variable dynamic system, a dynami... Control design is important for PEMFC (proton exchange membrane fuel cell) distributed power generator to satisfy user requirement for safe and stable operation. For a complex multi-variable dynamic system, a dynamic simulation model is first established. In view of close coupling and non-linear relationships between variables, the intelligent auto-adapted PI decoupling control method is used. From the simulation results it is found that, by bringing quadratic performance index in the single neuron, constructing adaptive PI controller, and adjusting gas flow rates through the second pressure relief valve and air compressor coordinately, both anode and cathode pressures can be maintained at ideal levels. 展开更多
关键词 proton exchange membrane fuel cell (PEMFC) distributed power generator pressure control flow rate PI decoupling control quadratic performance index single neuron adaptive PI controller.
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Design of a Three-Dimensional Centrifugal Fan with Controlled Blade Loading Approach 被引量:1
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作者 Jin Xiong Xin Ai +1 位作者 Kaibin Wang Jingyin Li 《Open Journal of Fluid Dynamics》 2017年第3期410-425,共16页
The high flow-rate centrifugal fan needs a three-dimensional impeller to achieve a high efficiency. In this paper, the design procedure of a high-efficiency three-dimensional centrifugal fan is presented. First, the m... The high flow-rate centrifugal fan needs a three-dimensional impeller to achieve a high efficiency. In this paper, the design procedure of a high-efficiency three-dimensional centrifugal fan is presented. First, the main dimensions of the fan were calculated by using the conventional one-dimensional method. Then, the blade loading or the angular momentum distribution along the meridional streamline on the blade surfaces is prescribed. After that, the three-dimensional blade is determined by using the streamline curvature method. With the aid of numerical simulations, the performance of the three-dimensional fan was improved and some of the key influence factors were investigated. The analyses indicate that, as to the high flow-rate centrifugal fan, the Stanitz modified formula is recommended to calculate the separation radius, rb. A proper increase in the separation radius is beneficial for the fan’s performance. It is also indicated that a decrease in the angular momentum on the hub leads to an increase in total pressure efficiency, under the condition of a given constant mean angular momentum at the outlet of the blade. In addition, the installation of a fairing on the hub plate can improve the fan’s efficiency evidently when the streamline curvature method is adopted to design the three-dimensional impeller. 展开更多
关键词 CENTRIFUGAL FAN controlled ANGULAR MOMENTUM High flow-rate
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Novel flow control mechanism based on improved BP neural network in cognitive packet network
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作者 单宝堃 李曦 +1 位作者 纪红 李屹 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第6期105-110,共6页
In this paper, a novel flow control mechanism in cognitive packet network (CPN) based on the improved back propagation (BP) neural network is proposed, considering the flow distribution status predicted by BP neural n... In this paper, a novel flow control mechanism in cognitive packet network (CPN) based on the improved back propagation (BP) neural network is proposed, considering the flow distribution status predicted by BP neural network when packets are routed. The objective is to increase the capacity of CPN and improve the quality of service (QoS) by achieving flow balance. Besides, considering the slow convergence speed of traditional BP algorithm and the quick change of the flow status in cognitive packet network, an improved BP algorithm with dynamic learning rate is designed in order to achieve a higher convergence speed. The mechanism, which we propose, regards the predicated traffic data as an important factor when packets are routed to implement flow control. By achieving balance, the quality of network can be improved obviously. The simulation results show that the proposed mechanism provides better average time delay and packets loss ratio. 展开更多
关键词 cognitive packet network flow control quality of service BP neural network.
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Effect of Source to Camera Distance and Count Rate on Intrinsic Uniformity of SPECT Gamma Camera
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作者 Sabrina Sarah Mahidul Haque Prodhan +1 位作者 Kawsar Hamid Fazlul Huq 《Open Journal of Medical Imaging》 2015年第2期78-84,共7页
In this research, the excellent parameter for regular Quality Control (QC) testing of intrinsic uniformity for dual-head Single Photon Emission Computed Tomography (SPECT) gamma camera is determined. The integral and ... In this research, the excellent parameter for regular Quality Control (QC) testing of intrinsic uniformity for dual-head Single Photon Emission Computed Tomography (SPECT) gamma camera is determined. The integral and differential intrinsic uniformity tests for both Useful Field Of View (UFOV) and Centre Field Of View (CFOV) were done by insertion a point-source of 99mTc in front of the detectors with detached collimators to measure the effect of source to camera distance and a count rate on intrinsic uniformity. The result reveals that the best intrinsic uniformity image is obtained at source-to-camera distance of 3 m and a count rate between 16 and 60 M. 展开更多
关键词 quality control (QC) INTRINSIC UNIFORMITY Useful Field of VIEW (UFOV) Centre Field of VIEW (CFOV) SOURCE to CAMERA DISTANCE Count rate
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