Low temperature exhaust gases carrying large amount of waste heat are released by steel-making process and many other industries, Organic Rankine Cycles （ORCs） are proven to be the most promising technology to re- c...Low temperature exhaust gases carrying large amount of waste heat are released by steel-making process and many other industries, Organic Rankine Cycles （ORCs） are proven to be the most promising technology to re- cover the low-temperature waste heat, thereby to get more financial benefits for these industries. The exergy analysis of ORC units driven by low-temperature exhaust gas waste heat and charged with dry and isentropic fluid was per- formed, and an intuitive approach with simple impressions was developed to calculate the performances of the ORC unit. Parameter optimization was conducted with turbine inlet temperature simplified as the variable and exergy effi- ciency or power output as the objective function by means of Penalty Function and Golden Section Searching algo- rithm based on the formulation of the optimization problem. The power generated by the optimized ORC unit can be nearly as twice as that generated by a non-optimized ORC unit. In addition, cycle parametric analysis was performed to examine the effects of thermodynamic parameters on the cycle performances such as thermal efficiency and exergy efficiency. It is proven that performance of ORC unit is mainly affected by the thermodynamic property of working fluid, the waste heat temperature, the pinch point temperature of the evaporator, the specific heat capacity of the heat carrier and the turbine inlet temperature under a given environment temperature.展开更多
Background Cardiac resynchronization therapy （CRT） with biventricular pacing improves cardiac function,functional capacity and quality of life in selected patients with heart failure.The current study aimed to evalu...Background Cardiac resynchronization therapy （CRT） with biventricular pacing improves cardiac function,functional capacity and quality of life in selected patients with heart failure.The current study aimed to evaluate the efficacy of the intracardiac electrogram （IEGM）-based optimization method,QuickOptTM,in Chinese patients treated with CRT.Methods Aortic time velocity integrals （AVTI） achieved at the sensed atrioventricular （AV）,paced AV and interventricular （VV） interval settings recommended by both QuickOptTM and standard echocardiographic optimization were measured in 101 patients.Consistency and the strength of the relationship between the two timing cycle optimization methods were assessed by intra-class correlation coefficient （ICC）.Results The ICC showed good agreement and correlation with what the AVTI achieved at the optimal sensed AV （ICC=0.9683 （0.9535-0.9785））,paced AV （ICC=0.9642 （0.9475-0.9757）） and VV （ICC=0.9730 （0.9602-0.9817）） interval settings determined by the two optimization methods.The average time required by echocardiographic optimization and by QuickOptTM were （78.32±32.40） minutes and （1.98±1.64） minutes respectively （P 〈0.0001）.Conclusion The QuickOptTM algorithm provides a quicker,simpler and reliable alternative to the standard method for timing cycle optimization.（ClinicaITrial.gov Reference Number：NCT00918294）展开更多
Automated material handling system(AMHS)ensures efficient transport of material from one place to another in the manufacturing area,which is widely adopted to transport wafers in semiconductor manufacturing facilities...Automated material handling system(AMHS)ensures efficient transport of material from one place to another in the manufacturing area,which is widely adopted to transport wafers in semiconductor manufacturing facilities.Efficient transportation in AMHS is crucial for maintaining manufacturing chain continuity,preventing machine idle time,and reducing cycle times by minimizing waiting time between operations.In this paper,we propose a spatio-temporal conflict elimination search(STCS)algorithm to improve the transportation efficiency of AMHS,which incorporates a job dispatching strategy based on global vehicle movement and idle vehicle management based on a triggered move least policy.Besides,STCS resolves the collisions of vehicles at merge nodes by a spatio-temporal elimination method.Simulation experiments on real-world fab data show that the STCS algorithm achieves competitive performance regarding to the production efficiency and vehicle utilization.Some key features are analyzed to identify the intrinsic properties of AMHS,which encourages decision-makers to adopt proper configuration in different manners to reduce costs and improve efficiency.展开更多
基金Sponsored by National Natural Science Foundation of China (5106602,U0937604)Natural Science Foundation of Yunnan Provincial (2008KA002,2008CD001)
文摘Low temperature exhaust gases carrying large amount of waste heat are released by steel-making process and many other industries, Organic Rankine Cycles （ORCs） are proven to be the most promising technology to re- cover the low-temperature waste heat, thereby to get more financial benefits for these industries. The exergy analysis of ORC units driven by low-temperature exhaust gas waste heat and charged with dry and isentropic fluid was per- formed, and an intuitive approach with simple impressions was developed to calculate the performances of the ORC unit. Parameter optimization was conducted with turbine inlet temperature simplified as the variable and exergy effi- ciency or power output as the objective function by means of Penalty Function and Golden Section Searching algo- rithm based on the formulation of the optimization problem. The power generated by the optimized ORC unit can be nearly as twice as that generated by a non-optimized ORC unit. In addition, cycle parametric analysis was performed to examine the effects of thermodynamic parameters on the cycle performances such as thermal efficiency and exergy efficiency. It is proven that performance of ORC unit is mainly affected by the thermodynamic property of working fluid, the waste heat temperature, the pinch point temperature of the evaporator, the specific heat capacity of the heat carrier and the turbine inlet temperature under a given environment temperature.
文摘Background Cardiac resynchronization therapy （CRT） with biventricular pacing improves cardiac function,functional capacity and quality of life in selected patients with heart failure.The current study aimed to evaluate the efficacy of the intracardiac electrogram （IEGM）-based optimization method,QuickOptTM,in Chinese patients treated with CRT.Methods Aortic time velocity integrals （AVTI） achieved at the sensed atrioventricular （AV）,paced AV and interventricular （VV） interval settings recommended by both QuickOptTM and standard echocardiographic optimization were measured in 101 patients.Consistency and the strength of the relationship between the two timing cycle optimization methods were assessed by intra-class correlation coefficient （ICC）.Results The ICC showed good agreement and correlation with what the AVTI achieved at the optimal sensed AV （ICC=0.9683 （0.9535-0.9785））,paced AV （ICC=0.9642 （0.9475-0.9757）） and VV （ICC=0.9730 （0.9602-0.9817）） interval settings determined by the two optimization methods.The average time required by echocardiographic optimization and by QuickOptTM were （78.32±32.40） minutes and （1.98±1.64） minutes respectively （P 〈0.0001）.Conclusion The QuickOptTM algorithm provides a quicker,simpler and reliable alternative to the standard method for timing cycle optimization.（ClinicaITrial.gov Reference Number：NCT00918294）
基金supported by the Special Project for Knowledge Innovation of Hubei Province(No.2022013301015175)the National Natural Science Foundation of China(No.62202192).
文摘Automated material handling system(AMHS)ensures efficient transport of material from one place to another in the manufacturing area,which is widely adopted to transport wafers in semiconductor manufacturing facilities.Efficient transportation in AMHS is crucial for maintaining manufacturing chain continuity,preventing machine idle time,and reducing cycle times by minimizing waiting time between operations.In this paper,we propose a spatio-temporal conflict elimination search(STCS)algorithm to improve the transportation efficiency of AMHS,which incorporates a job dispatching strategy based on global vehicle movement and idle vehicle management based on a triggered move least policy.Besides,STCS resolves the collisions of vehicles at merge nodes by a spatio-temporal elimination method.Simulation experiments on real-world fab data show that the STCS algorithm achieves competitive performance regarding to the production efficiency and vehicle utilization.Some key features are analyzed to identify the intrinsic properties of AMHS,which encourages decision-makers to adopt proper configuration in different manners to reduce costs and improve efficiency.
