Optimization and Performance Comparison of Hairpin?Winding PMSM for Electric Vehicles Under Drive Cycle

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 resistance.And 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 temperatures.Then,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 motor.Finally,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 method.The 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.

A Comparison of GaN VS GaAs System Performance

Traditionally RF power amplifiers used Gallium Arsenide(GaAs) technology which has a well behaved and understood performance. Over the past few years Gallium Nitride(GaN) technology is replacing GaAs because GaN is more efficient and has a higher power density resulting in higher power MMICs and FETs.Subject to system link budgets, we usually want to run a given amplifier as close to saturation as possible to minimize CAPEX costs. Running an amplifier closer to saturation causes many non-linear effects that can cause link performance degradation and interfere with other users.To better understand and quantify the differences between GaN and GaAs amplifiers and the impact of this on system performance, some amplifier and system measurements will be taken. The findings will be documented in a white paper.

Research on the Comparison between the Different Policies by Service Level and Inventory Level Performance of Auto Parts in N.A.C.C.(North Automobile Components Company)

As after sales services become more and more popular,particularly preven­tive or corrective maintenance,the intervention and repair of the custom­er’s goods in a timely and efficient manner ensure customer satisfaction and contribute to the establishment of brand image in the market of the suppliers.The availability and quality of spare parts are key elements of this strategy while ensuring minimal management costs.The reuse of spare parts retrieved from customer systems is a growing maintenance strategy practice which impacts the traditional spare parts supply chain.This reuse is primarily driven by extending the economic life of goods,initially re­garded as waste and therefore without added value,by transforming them into valuable spare parts that can be reused;secondly,for environmental or regulatory reasons,demanding responsibility for the treatment of products at the end of their life;and thirdly,to improve the availability of parts for maintenance,especially parts that the organization can no longer purchase or that are impacted by other issues.It also involves the analysis of their condition and their eventual return to working order as they are retrieved from the customer’s systems in a defective condition.In this paper,we will identify and classify the different customers and spare parts by estimating the critical level of rationing policy based on forecasts,identify the thresh­olds of inventory management policies,and finally,compare the different policies by service level and inventory level performance for the N.A.C.C.company.

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

In the blockchain,the consensus mechanism plays a key role in maintaining the security and legitimation of contents recorded in the blocks.Various blockchain consensus mechanisms have been proposed.However,there is no technical analysis and comparison as a guideline to determine which type of consensus mechanism should be adopted in a specific scenario/application.To 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 probability.The results show that the consensus process is affected by both network resource(computation power/coin age,buffer size)and network load conditions.In 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.

Correlation Study of Operational Data and System Performance of District Cooling System with Ice Storage

The district cooling system (DCS) with ice storage can reduce the peak electricity demand of the business district buildings it serves, improve system efficiency, and lower operational costs. This study utilizes a monitoring and control platform for DCS with ice storage to analyze historical parameter values related to system operation and executed operations. We assess the distribution of cooling loads among various devices within the DCS, identify operational characteristics of the system through correlation analysis and principal component analysis (PCA), and subsequently determine key parameters affecting changes in cooling loads. Accurate forecasting of cooling loads is crucial for determining optimal control strategies. The research process can be summarized briefly as follows: data preprocessing, parameter analysis, parameter selection, and validation of load forecasting performance. The study reveals that while individual devices in the system perform well, there is considerable room for improving overall system efficiency. Six principal components have been identified as input parameters for the cold load forecasting model, with each of these components having eigenvalues greater than 1 and contributing to an accumulated variance of 87.26%, and during the dimensionality reduction process, we obtained a confidence ellipse with a 95% confidence interval. Regarding cooling load forecasting, the Relative Absolute Error (RAE) value of the light gradient boosting machine (lightGBM) algorithm is 3.62%, Relative Root Mean Square Error (RRMSE) is 42.75%, and R-squared value (R2) is 92.96%, indicating superior forecasting performance compared to other commonly used cooling load forecasting algorithms. This research provides valuable insights and auxiliary guidance for data analysis and optimizing operations in practical engineering applications. .

Comparison of pharmacokinetics of different oral Panax notoginseng saponins using ultra-high performance liquid mass spectrometry

Objective:To discuss and compare the plasma pharmacokinetics after three oral Panax notoginseng saponin(PNS)administrations in beagle dogs.PNS is the main active ingredient of the traditional Chinese medicine(TCM)Panax notoginseng.Although its outstanding therapeutic efficacy has been demonstrated by various researchers,its broader application is restricted by the low bioavailability of PNS.Methods:An ultra-high performance liquid chromatographyetandem mass spectrometry(UPLC-MS/MS)method for the simultaneous quantification of notoginsenoside R1,ginsenoside Rg1,ginsenoside Rb1,ginsenoside Rd,and ginsenoside Re in beagle dog plasma was developed and validated.The plasma samples were subjected to liquideliquid extraction with acetone and methanol,and separated on an ACQUITY C18 column(100×2.1 mm ID,1.7 mm)using acetonitrile and water as the mobile phase with a run time of 4.5 min.Results:The analytes were detected without interference in Selected Reaction Monitoring mode with positive electrospray ionization.The validated method was successfully used in comparative pharmacokinetic studies of the five saponins in beagle dogs after oral administration of three PNS preparations.Blood samples were collected up to 192 h after administration and pharmacokinetic parameters were calculated using DAS 3.20 and SPSS 17.0.The AUC_(0-t)values of Re and R1 were significantly higher in soft capsules than in hard capsules.However,the AUC_(0-t)values between hard and soft capsules were not significantly different for the other three componentsdRb1,Rd and Rg1.Conclusion:Our intuitive analysis suggests that the bioavailability of PNS in soft capsules is greater than in hard capsules.

PERFORMANCE EVALUATION AND COMPARISON OF THREE COUNTING BLOOM FILTER SCHEMES

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.

PERFORMANCE COMPARISON OF ECG COMPRESSION ALGORITHMS BASED ON CLINICAL DIAGNOSIS

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.

发电厂DCS控制系统的性能测试分析

阐述发电厂DCS控制系统的特征、性能测试的必要性。探讨发电厂DCS控制系统性能测试的实践应用,包括容错冗余性能测试、控制处理周期性能测试、控制响应时间性能测试、实时性性能测试。

Performance Model Analysis of Armenian Premier League Soccer Players Using Global Positioning System Technology and Comparison between European Championship

The aim of this research was to analyze the PPM of Armenian Premier League using 25 GPS 10 Hz(K-Sport,Montelabbate,Italy),in order to compare data from literature from major European championship.In total 25 matches were analyzed from one team militant in Armenian Premier League(10 wins,10 loses and 5 draws),33 different players(age 24.3±4.2,height 1.76±4.2 and weight 74±3.5)and in total 270 performances(10.8 for matches).Matches were divided in First Half(T1),Second Half(T2),Second Half Substitution(T2 Sub),Full Match,Full Match Substitution(Full Match Sub)and Total Match(Total)that include all the players detected during a games.Furthermore,all matches were divided even by quarters 0-15,15-30,30-45,45-60,60-75 and 75-90,only players that played all match were included in this analyses,in order to check the performance decreasing during the time.All data were added in an Excel Spreadsheet in order to build a database,to organize and better analyze data,cataloging events for data,results,and role of players.Average data from Armenian Premier League in comparison with literature data from European and Italian Championship show that in every parameter,the Armenian Premier League is under the average.This is obviously related to the non-high level of the Armenian football that is in fact placed at the 106°place of the FIFA ranking(update 7 June 2019).Physical data represent an indicator of performance but also of the qualitative level of the league and of individual players.For this reason,the use of the match analysis can be decisive to verify the PPM,in order to better evaluate the championships,teams,and players,in order to build an easier search and discovery of talents.

DCS性能评价标准在华东电网应用探讨

简要介绍了北美电力可靠性协会(NERC)的扰动控制标准(DCS),通过对DCS技术特点的分析,阐明了DCS与控制区区域控制偏差(ACE)、电网频率以及控制性能标准(CPS)之间的影响。结合华东电网典型扰动事故分析,认为DCS指标可以有效地反映控制区事故备用能力。针对华东电网各省市能量管理系统(EMS)的特点,提出了在华东电网实施DCS的技术可行性,指出实施DCS标准为华东电网合理配置备用容量提供了技术评价手段,并节约了系统资源。最后结合DCS性能监视要求,提出了对网、省(市)自动发电控制(AGC)软件进行相应调整的思路。

基于Jini技术的DCS系统体系结构改进

主要探讨了现有DCS设备联网的体系结构和Jini体系结构,分析两者的实现功能和提高系统动态可扩展性的方法.利用Jini技术的多虚拟机环境和嵌入式操作系统,对DCS的多子网结构进行了改进,并针对DCS中的异构设备,提出了4种提高设备的动态可扩展性的方法,支持各种DCS控制设备的动态网络化.

Interspecific comparison of the flight performance between sparrowhawks and common buzzards migrating at the Falsterbo peninsula： A radar study

In order to compare the two species＇ flight performance over the exposed and windy Falsterbo Peninsula, where thermal conditions seldomly are very favorable, we used tracking radar to study flight parameters of sparrowhawks Accipiter ni- sus and common buzzards Buteo buteo during autumn migration. The results showed a clear difference between sparrowhawks and common buzzards in their flight altitudes and speeds, and in the wind conditions they encountered. Common buzzards had higher flight altitudes and were more selective of wind. Flight altitude was negatively related to the wind speed, which was most pronounced for common buzzards. Sparrowhawks had higher mean air- and cross-country speeds than common buzzards. Air- speed was negatively related, whereas ground and cross-country speeds were positively related to the tailwind component for both raptors. The differences between sparrowhawks and buzzards could to a large degree be explained by a larger dependence on thermal soaring among the common buzzards; a strategy associated with selectivity for favourable thermal and wind conditions during migratory flight. An additional important explanation for the interspecific differences was the habit of the sparrowhawks to combine migratory flight with hunting for prey, which makes it prone to fly at lower altitudes and use flapping flight to a much larger degree than common buzzards which do not forage during their migratory passage of the Falsterbo Peninsula [Current Zoo- logy 60（5）： 670-679, 2014].

基于Symphony DCS Composer组态语言与C语言联合编程的在线性能计算

提出了1种采用美国ABB公司的Symphony DCS Composer组态语言与C语言联合编程的方法,采用C语言编制在线性能计算程序,Composer组态语言调用C语言程序,将DCS实时数据作为计算数据,计算得到单元机组能耗特性。C语言程序包含了基于IAPWS-IF97公式的焓熵值计算程序,集成一体化计算环境,无需调用其它程序,解决了DCS组态语言存在的对于复杂算法的局限性,实现了机组的在线性能计算。以某电厂1台660 MW机组为研究对象,对机组660 MW负荷下的煤耗进行了计算,计算结果误差在允许范围内,表明该在线计算方法可行。

基于虚拟DCS与SIS的数据比较系统的开发

以虚拟分散控制系统(DCS)仿真控制技术和系统的相似度理论为基础,利用监控信息系统(SIS)和仿真系统的互联条件,开发了用于大型发电厂真实数据和仿真数据的比较系统。采用系统的相似度理论实现了相似度的算法,利用实时和关系数据库技术对数据进行管理和计算,同时运用ADO(activeX data object)接口技术方便地实现了数据库和应用程序的数据连接。

火电厂DCS性能考核试验与可靠性分析

针对某600 MW进口机组分散控制系统(DCS)性能现状,分析了DCS性能下降的原因,提出了增加其性能考核的试验内容,并对采用性能考核试验提高DCS可靠性问题进行了讨论。对完善DCS性能考核试验,具有较好的作用。

国产DCS的性能分析

介绍了国产DCS成功应用于工业过程,并就主要的国产DCS性能展开了分析和比较,希望国产DCS的性能更上一个台阶。

Incorporating Pay Basis into Pay Comparison： The Relationships among Over/Underpayment, Pay for Performance and Pay Level Satisfaction

Drawing on the discrepancy model, we re-examine the impact of pay comparison on employees＇ pay level satisfaction by taking pay basis and pay program into account. Actual pay data from 382 Chinese employees, along with their self-reported pay level satisfaction, provides support for our research model. Specifically, results show that the positive effect of over/underpayment on pay level satisfaction is more robust than that of internal pay standing, indicating the importance of pay basis for pay satisfaction perception. In addition, the positive relationship between internal pay standing and pay level satisfaction is weaker among employees who are in a pay program of high pay-for-performance intensity. We conclude by discussing the theoretical and practical implications of these findings.

提升DCS控制性能以实现IMC-PID鲁棒控制

本文介绍了兼顾鲁棒性和性能指标的IMC-PID控制器的设计方法,并通过DCS上的组态来实现这种控制算法,使DCS的PID控制算法提升为IMC-OID鲁棒控制算法、使控制系统性能与鲁棒性大为提高。为便于工业应用,提出一种简便的闭环系统辨识算法,与IMC-PID鲁棒控制器设计结合起来,形成一个软件包,将它用于某厂常减压加热炉上,取得很好的控制效果。