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performance comparison OF ECG COMPRESSION ALGORITHMS BASED ON CLINICAL DIAGNOSIS

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Journal of Shanghai Jiaotong university(Science) 2001年第1期6卷 21-26页

作者：李顺山李高平乐园庄天戈 Dept. of Biomedical Eng. Shanghai Jiaotong Univ. Shanghai Zhongshan Hospital Shanghai 200032

This paper reviewed the recent progress in the field of electrocardiogram (ECG) compression and compared the efficiency of some compression algorithms. By experimenting on the 500 cases of ECG signals from the ECG database of China, it obtained the numeral indexes for each algorithm. Then by using the automatic diagnostic program developed by Shanghai Zhongshan Hospital, it also got the parameters of the reconstructed signals from linear approximation distance threshold (LADT), wavelet transform (WT), differential pulse code modulation (DPCM) and discrete cosine transform (DCT) algorithm. The results show that when the index of percent of root mean square difference(PRD) is less than 2.5%, the diagnostic agreement ratio is more than 90%; the index of PRD cannot completely show the damage of significant clinical information; the performance of wavelet algorithm exceeds other methods in the same compression ratio (CR). For the statistical result of the parameters of various methods and the clinical diagnostic results, it is of certain value and originality in the field of ECG compression research.

关键词： compression algorithms performance comparison clinical diagnosis

Optimization and performance comparison of Hairpin?Winding PMSM for Electric Vehicles Under Drive Cycle

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Transactions of Nanjing University of Aeronautics and Astronautics 2021年第5期38卷 713-725页

作者： LIU Huijuan SONG Tengfei DU Jinwen LIU Bo School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044P.R.China Electric Engineering Department Suzhou Inovancel Technology Co.LtdSuzhou 215100P.R.China

Aiming at the problem of large AC copper loss caused by skin effects and proximity effects,and low efficiency at high speed of the hairpin-winding permanent magnet synchronous motor(PMSM)for electric vehicles(EVs),this paper firstly established the electromagnetic analytical model of the hairpin winding to calculate AC *** the finite element model(FEM)of the hairpin-winding driving motor is established to calculate the AC characteristic of the hairpin winding at different speeds and ***,combining modified particle swarm optimization(MPSO)and FEM,a 60 k W hairpin-winding PMSM is optimized under driving cycle conditions,and the electromagnetic performance and heat dissipation performance are compared with that of the traditional strand-winding ***,a prototype is made and an experimental platform is built to test the efficiency Map and temperature rise of the hairpin-winding motor over the whole speed range and verify the accuracy of the proposed optimization design *** results show that the hairpin-winding PMSM not only has higher slot filling rate,high?efficiency range and power density,but also has better heat dissipation performance,which is suitable for application in the field of electric vehicles.

关键词： electric vehicles(EVs) hairpin-winding optimization design drive cycle performance comparison

performance Optimization and comparison of the Alternating Direction Implicit CFD Solver on Multi-core and Many-Core Architectures

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Chinese Journal of Electronics 2018年第3期27卷 540-548页

作者： DENG Liang ZHAO Dan BAI Hanli WANG Fang Computational Aerodynamics Institue China Aerodynamics Research and Development Center Collaborative Innovation Center of High performance Computing National University of Denfense Technology School of Computer National University of Denfense Technology

We accelerate a double precision Alternating direction implicit(ADI) solver for three-dimensional compressible Navier-Stokes equations from our in-house Computational fluid dynamics(CFD) software on the latest multi-core and many-core architectures(Intel Sandy Bridge CPUs, Intel Many integrated core(MIC) coprocessors and NVIDIA Kepler K20c GPUs). Some performance optimization techniques are detailed discussed. We provide an in-depth analysis on the performance difference between Sandy Bridge and MIC. Experimental results show that the proposed GPU-enabled ADI solver can achieve a speedup of 5.5 on a Kepler GPU in contrast to two Sandy Bridge CPUs and our optimization techniques can improve the performance of the ADI solver by 2.5-fold on two Sandy Bridge CPUs and 1.7-fold on an Intel MIC coprocessor. We perform a cross-platform performance analysis(between GPU and MIC), which serves as case studies for developers to select the right accelerators for their target applications.

关键词： Multi-block Structured grid Alternating direction implicit(ADI) CFD solver Sandy bridge MIC GPU Optimization techniques performance comparison

The decoder performance comparison in the closed-loop BMI system based on MPC

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The decoder performance comparison in the closed-loop BMI sy...

performance analysis and comparison of PoW,PoS and DAG based blockchains

第37届中国控制会议

作者： Hongguang Pan Wenyu Mi Jinggao Sun Baocang Ding College of Electric and Control Engineering Xi'an University of Science and Technology Key Laboratory of Advanced Control and Optimization Technology of Ministry of Education East China University of Science and Technology School of Electronic and Information Engineering Xi'an Jiaotong University

Brain-machine interface(BMI) can be used to translate the neural activities of the brain into the control signals for the artificial arm, aiming to offer the disabled patients greater interaction with the world. In recent years, some emerging technologies, such as back propagation(BP) neural network and recurrent neural networks(RNN) with long-short term memory(LSTM), have been adopted in many fields. Hence, we firstly design four decoders based on the classical Wiener filter and Kalman filter, and the emerging BP neural network and RNN with LSTM, and compare the performance of these decoders offline. Secondly, considering the advantages of the model predictive control(MPC), we design an auxiliary controller based on MPC algorithm to form a closed-loop BMI system, and compare the performance of four decoders online.

关键词： Decoder design Model predictive control performance comparison Online Offline

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Digital Communications and Networks 2020年第4期6卷 480-485页

作者： Bin Cao Zhenghui Zhang Daquan Feng Shengli Zhang Lei Zhang Mugen Peng Yun Li The State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing100876China The State Key Laboratory of Integrated Services Networks(Xidian University) Xian710000China School of Communications and Information Engineering and Chongqing Key Lab of Mobile Communications Technology Chongqing University of Posts and TelecommunicationsChongqing400065China The Guangdong Key Laboratory of Intelligent Information Processing College of Electronic and Information EngineeringShenzhen UniversityShenzhen518060China College of Information Engineering Shenzhen UniversityShenzhen518060China School of Engineering University of GlasgowGlasgowG128QQUK

In the blockchain,the consensus mechanism plays a key role in maintaining the security and legitimation of contents recorded in the *** blockchain consensus mechanisms have been ***,there is no technical analysis and comparison as a guideline to determine which type of consensus mechanism should be adopted in a specific scenario/*** this end,this work investigates three mainstream consensus mechanisms in the blockchain,namely,Proof of Work(PoW),Proof of Stake(PoS),and Direct Acyclic Graph(DAG),and identifies their performances in terms of the average time to generate a new block,the confirmation delay,the Transaction Per Second(TPS)and the confirmation failure *** results show that the consensus process is affected by both network resource(computation power/coin age,buffer size)and network load *** addition,it shows that PoW and PoS are more sensitive to the change of network resource while DAG is more sensitive to network load conditions.

关键词： Blockchain Proof of work Proof of stake Direct acyclic graph performance comparison

performance EVALUATION AND comparison OF THREE COUNTING BLOOM FILTER SCHEMES

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Journal of Electronics(China) 2009年第3期26卷 332-340页

作者： Zhang Jin Wu Jiang-xing Lan Julong Liu Jianqiang National Digital Switching System Engineering and Technology Research Center Zhengzhou 450002 China

The Counting Bloom Filter （CBF） is a kind of space-efficient data structure that extends a Bloom filter so as to allow approximate multiplicity queries on a dynamic multi-set. This paper evaluates the performance of multiplicity queries of three simple CBF schemes-the Naive Counting Bloom Filter （NCBF）, the Space-Code Bloom Filter （SCBF） and the d-left Counting Bloom Filter （dlCBF）-using metrics of space complexity and counting error under both uniform and zipfian multiplicity distributions. We compare their counting error under same space complexity, and their space complexity when similar counting errors are achieved respectively. Our results show that dICBF is the best while SCBF is the worst in terms of both space-efficiency and accuracy. Furthermore, the performance gap between dlCBF and the others has a trend of being enlarged with the increment of space occupation or counting accuracy.

关键词： Counting Bloom Filter (CBF) performance comparison

Efficiency comparison and performance analysis of internally-cooled liquid desiccant dehumidifiers using LiCl and CaCl2 aqueous solutions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2020年第1期21卷 44-63页

作者： Dong-gen PENG Shun-yi LI Dan-ting LUO Yu-ting FU Xiao-song CHENG Yin LIU School of Civil Engineering and Architecture Nanchang UniversityNanchang 330031China School of Energy and Environment Southeast UniversityNanjing 210096China School of Environmental Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Henan Zhongrui Refrigeration Technology Co. LtdXinzheng 451191China

Internally-cooled dehumidifiers are efficient liquid desiccant dehumidifiers, whose performance is mainly determined by the device structure and operating conditions. Based on energy and mass conservation in the air, solution, and cooling water in the device, mathematical models are built and their theoretical performance is simulated and analyzed in this paper. A novel measure of dehumidification efficiency is introduced to evaluate the performance of internally-cooled dehumidifiers, in which the equilibrium humidity ratio of the inlet solution is calculated according to the minimum temperature in the inlet solution and the cooling water. Numerical simulations show that a counter flow between air and solution is always the most efficient, followed by cross flow, and parallel flow is the least efficient. Cooling water with the same flow direction as the solution performs better than that with a counter flow, with approximately a 5% improvement in efficiency. Compared with Ca Cl2, the dehumidification efficiency of a Li Cl solution is greater by 60%, while its exergy efficiency is less by 16%. Dehumidification efficiency can be improved with the number of air-solution heat transfer units(NTUa-s) increasing, and reduced with the air mass flow rate raised. With NTUa-s increasing, exergy efficiency can be improved, and an increase in mass flow rate of cooling water results in a decrease of efficiency. Higher solution concentration and lower inlet temperature of solution and air can achieve both higher dehumidification efficiency and exergy efficiency.

关键词： Liquid desiccant Internally-cooled dehumidifiers performance comparison Dehumidification efficiency Exergy efficiency

A Comparative Study on the performance of Typical Types of Bionic Groove Dry Gas Seal based on Bird Wing

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Journal of Bionic Engineering 2016年第2期13卷 324-334页

作者： Jinbo Jiang Xudong Peng Jiyun Li Yuan Chen School of Mechanical Engineering Zhejiang University of Technology Hangzhou 310014 China

A series of bionic grooves based on bird wing, such as cluster spiral groove, multi-array spiral groove and flow-split spiral groove, are introduced to improve the film stiffness and sealing properties of dry gas seal. A theoretical model solved with Finite Difference Method （FMD） is developed to study the static sealing performance, such as film stiffness and leakage rate of these bionic groove dry gas seals. Then, a performance comparative study between the bionic groove dry gas seals and common spiral groove dry gas seal with different groove geometry parameters such as groove depth ratio, spiral angle and micro groove number under different average linear velocity at seal ring face and seal pressure is carried out. The closing force, film thickness and leakage rate of dry gas seals with bionic grooves and common spiral groove are measured experimentally. Results show that cluster spiral groove and multi-array spiral groove dry gas seals have superiority in the film stiffness and stiffness-leakage ratio compared with common spiral groove under the condition of high-speed and low-pressure, while flow-split spiral groove dry gas seal has no obvious advantages of performance. Film stiffness of cluster spiral groove dry gas seal and stiffness-leakage ratio of multi-array spiral groove dry gas are 20% and 50% larger than that of common spiral groove dry gas seal, respectively, which are verified by the experimental results.

关键词： bionic groove dry gas seal film stiffness performance comparison

Experimental Analyses of Moderately High-Temperature Heat Pump Systems with R245fa and R1233zd(E)

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Energy Engineering 2022年第6期119卷 2231-2242页

作者： Ting Chen Oh Kyung Kwon State Key Laboratory of Fluid Power&Mechatronic Systems Zhejiang UniversityHangzhou310027China Clean Energy R&D Department Korea Institute of Industrial TechnologyCheonan31056Republic of Korea

With the limited production and use of R245fa,environmentally friendly refrigerant has attracted the attention of *** to the similar thermal characteristics,R1233zd(E)is considered to be an ideal substitute for R245fa in heat pump *** this study,the performance and economic analysis of heat pump systems with R245fa and R1233zd(E)as refrigerants are carried *** results show that the total cost of R1233zd(E)system is more than 10%higher than that of R245fa system under the same heating *** the increase of condensation temperature,the heating capacity of both systems decreases,and with the increase of evaporation temperature,the heating capacity *** variation trend of coefficient of performance(COP)of the two systems is similar to that of heating *** the same operating conditions,the COP of R1233zd(E)system is 19.2%higher than that of R245fa system,and the volumetric heat capacity of R1233zd(E)is 9.0%–13.9%lower than that of *** economic analysis results show that the investment cost of R1233zd(E)system is low under the same heat load.

关键词： Heat pump R1233zd(E) R245fa performance comparison economic analysis