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A Sensorless I-F Start-up Strategy for Flying Start of Ultra-high-speed Permanent Magnet Motors based on Short-circuit Transient Differentiation 认领 引用
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作者 Wei Chen Peizhe Liu +2 位作者 Lixiang Zhu Xinmin Li Zhezhun Xu 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2026年第2期228-239,共12页
Conventional current-to-frequency(I-F)start-up strategies apply only to zero-speed conditions.When a nonzero initial speed(referred to as a flying start)exists,loss of synchronism is likely to occur because the virtua... Conventional current-to-frequency(I-F)start-up strategies apply only to zero-speed conditions.When a nonzero initial speed(referred to as a flying start)exists,loss of synchronism is likely to occur because the virtual synchronous reference frame fails to align with the rotor flux linkage direction.To meet the flying start requirements of ultra-highspeed permanent magnet motors,this paper proposes a sensorless I-F start-up strategy for flying starts based on differential analysis of short-circuit transients.Upon power-up,the inverter places the three-phase stator windings in a controlled short-circuit state and applies two short-duration short-circuit pulses at different instants.By sampling the phase variation of the stator current vectors during the two shortcircuit transients,differential current characteristics are extracted to rapidly estimate the initial rotor position and speed,thereby facilitating smooth I-F start-up.The proposed method overcomes the limitations of conventional I-F strategies confined to zero-speed start-up and is applicable to oil-film and airbearing supported motor systems.Experimental results validate a smooth flying start featuring continuous and impact-free stator currents,effective suppression of mechanical friction prior to airfilm formation,and the enhanced stability and robustness of I-F start-up. 展开更多
关键词 Ultra-high-speed permanent magnet motor Current-to-frequency(I-F)start-up Flying start Short-circuit transient Sensorless control
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Prediction of ferrite transformation start temperature in hot-rolled aluminum bearing dual-phase steel based on combination of metallurgical principles and experimental data 认领 引用
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作者 Xiao-Guang Zhou Si-Qiao Wang +5 位作者 Xu-Yuan Zhang Hong-Bing Wang Chun-Yang Shu Xin-Yao Zhang Si-Wei Wu Zhen-Yu Liu 《Journal of Iron and Steel Research International》 SCIE EI CSCD 2026年第1期149-158,共10页
The accurate establishment of a ferrite transformation start temperature model is crucial to design a reasonable controlled rolling process and ensure uniform microstructure in aluminum bearing dual-phase steel.The me... The accurate establishment of a ferrite transformation start temperature model is crucial to design a reasonable controlled rolling process and ensure uniform microstructure in aluminum bearing dual-phase steel.The measurements of the expansion-temperature curves of aluminum bearing dual-phase steel under continuous cooling and isothermal conditions are presented,utilizing a dynamic transformation dilatometer experiment.Based on these expansion-temperature curves,the start temperature and incubation time of ferrite transformation were determined,elucidating the influence of process parameters on both the incubation time and the start temperature of ferrite transformation.By integrating metallurgical principles with measured incubation time of ferrite transformation,and considering the effects of temperature and strain,a fitting model for the variation in volume free energy during ferrite nucleation was derived.Building upon this foundation,a high-precision incubation time of ferrite transformation mathematical model for the experimental steel was established.To more accurately calculate the start temperature of ferrite transformation under continuous cooling conditions,the Scheil’s additivity rule was modified to account for the effects of deformation and cooling rate.The results indicate that the modification coefficient decreases with increasing the cooling rate and strain,thereby significantly improving the accuracy of calculating the starting temperature of ferrite transformation using the modified additivity rule. 展开更多
关键词 Dual-phase steel Ferrite transformation Incubation time Ferrite transformation start temperature Model
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Research on hill start assist control with ASR for electric vehicles on split-μroad 认领 引用
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作者 Hongliang Wang Jinxiang Wu +3 位作者 Yongjun Yan Dawei Pi Pengyu Xue Yibo Hu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2026年第1期469-477,共9页
When the vehicle is on a split-μ ramp and is restricted by the differential's torque-equalizing characteristic,a sig-nificant functional conflict may occur between the driving force limitation requirement of the ... When the vehicle is on a split-μ ramp and is restricted by the differential's torque-equalizing characteristic,a sig-nificant functional conflict may occur between the driving force limitation requirement of the acceleration slip regulation(ASR)control strategy for low-adhesion side wheels and the driving force enhancement demand of the entire vehicle during hill starting.Aiming at this problem,this paper proposes an ASR control strategy for the start-up of the electric vehicle on the split-μramp based on the combined control architecture of the service brake system and the parking brake system.First,the relationship between the driving force,braking force,and road adhesion at the slip moment is analyzed,and the ground adhesion estimation algorithm based on the dynamic equation of the driving wheel slip moment is proposed.Second,a service braking torque control model is constructed,and an ASR controller method based on the super-twisting sliding mode control(STSMC)algorithm is proposed to study the hill start assist(HSA)control strategy of electric vehicles on split-μroads.Finally,the proposed control strategy is si-mulated in this paper.The simulation results show that the proposed strategy can accurately estimate the ground adhesion of the driving wheel on the low-adhesion side effectively preventing the vehicle from slipping back,and improving the dynamic performance of the vehicle under harsh conditions. 展开更多
关键词 ASR Centralized drive Combined control Hill start
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智能管道应力分析软件Start-Prof工程应用研究 认领 引用
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作者 李天 纪志远 +2 位作者 李博生 张鹏飞 李哲 《海洋工程装备与技术》 2026年第1期84-93,共10页
针对工业管道应力分析领域的关键技术需求,以国产化智能管道应力分析软件Start-Prof为研究对象,通过对比国际主流软件CAESARⅡ的工程应用表现,系统验证其技术可靠性与工程适用性。研究以典型管道系统(海水、原油)为例,建立多工况有限元... 针对工业管道应力分析领域的关键技术需求,以国产化智能管道应力分析软件Start-Prof为研究对象,通过对比国际主流软件CAESARⅡ的工程应用表现,系统验证其技术可靠性与工程适用性。研究以典型管道系统(海水、原油)为例,建立多工况有限元模型,重点考察内压、温度、地震及风载等复合载荷作用下的应力响应特性。结果表明:Start-Prof计算精度与CAESARⅡ保持趋势一致性,二次应力的校核更为保守,所有工况应力比均控制在规范限值内,位移与模态分析结果误差小于2%,研究结果可为后续国产化软件Start-Prof在工程中推广应用提供有力保障。 展开更多
关键词 Start-Prof CAESARⅡ 应力分析 有限元模型 工程应用
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问题·活动·评价:小学英语Start to read板块教学新范式 认领 引用 被引量：1
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作者 沈洁 《教育科学论坛》 2026年第5期19-22,共4页
聚焦PEP新教材Start to read板块教学,针对传统阅读启蒙课存在的思维培养不足、教学活动单一等问题,提出“问题·活动·评价”三位一体的教学新范式。通过构建层级化问题体系引导思维进阶,设计梯度式活动促进语篇理解,实施全程... 聚焦PEP新教材Start to read板块教学,针对传统阅读启蒙课存在的思维培养不足、教学活动单一等问题,提出“问题·活动·评价”三位一体的教学新范式。通过构建层级化问题体系引导思维进阶,设计梯度式活动促进语篇理解,实施全程化评价保障学习效果。研究表明,该范式能有效提升学生阅读兴趣与综合语言能力,为小学英语阅读启蒙教学提供可复制、可推广的创新路径。 展开更多
关键词 PEP新教材 Start to read板块 教学范式 问题导向 活动设计 全程评价
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Numerical Simulation Study of Power Output Characteristics of Vertical-Axis Self-starting Power Generators 认领 引用
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作者 JIN Feng HUANG Zhou-yi 《船舶力学》 EI CSCD 北大核心 2026年第6期894-909,共16页
To address the difficulty in self-starting for vertical-axis water turbines with fixed pitch angles and to improve the efficiency of marine energy utilization,a hybrid power generation device was proposed that incorpo... To address the difficulty in self-starting for vertical-axis water turbines with fixed pitch angles and to improve the efficiency of marine energy utilization,a hybrid power generation device was proposed that incorporated a Savonius-type wind rotor to assist in starting the vertical-axis water turbine.Numerical simulations were conducted to investigate the dynamic output characteristics of this integrated device.Firstly,a three-dimensional two-phase flow numerical tank was constructed using Fluent software,and the mesh partitioning scheme was determined by comparing the values of the power output parameters of the device under different mesh densities,and at the same time,the validity of the numerical tank was confirmed.Secondly,the established numerical tank was used to simulate the variation law of torque,speed and power coefficient of power generation devices under different flow field conditions with different water wheel blade numbers,radius ratios and height ratios.The results show that the device performs better in terms of torque stability,speed characteristics,and energy utilization in the simulated working condition range when the water wheel blades are 3 to 4,the radius ratio is 0.25 to 0.375,and the height ratio is 1/6 to 1/3.The device is able to start quickly in the presence of wind,and the power coefficient reaches 0.3 to 0.4 or even exceeds 0.4,with good starting and power generation performance.The research results can provide a reference for the design and application of the device. 展开更多
关键词 Fluent vertical-axis power generator numerical simulation starting performance energy utilization characteristics
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Study on Risk Management of API Starting Materials Based on FMEA 认领 引用
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作者 Chen Xiaofeng Chen Yuwen 《Asian Journal of Social Pharmacy》 CAS 2026年第1期60-69,共10页
Objective To reduce the risk of choosing API starting materials incorrectly since the rationality of its selection and the scientific justification of quality research have a significant impact on the quality control ... Objective To reduce the risk of choosing API starting materials incorrectly since the rationality of its selection and the scientific justification of quality research have a significant impact on the quality control of API.Methods Failure mode and effects analysis(FMEA)strategy was used to do the risk management of API starting materials of D company.Results and Conclusion The FMEA method can improve the risk management of the research of API starting materials for D company,which is still effective to apply the method to C company and R company. 展开更多
关键词 drug substance starting material risk management FMEA
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Implementation and Project Management Strategy of Black Start Function in Utility-Scale Energy Storage Systems 认领 引用
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作者 Ruo Jia 《Journal of Electronic Research and Application》 2026年第7期101-107,共7页
As renewable penetration deepens, power system inertia and black-start capability decline, raising concerns about grid resilience. Utility-scale battery energy storage systems (BESS)with grid-forming (GFM)inverters of... As renewable penetration deepens, power system inertia and black-start capability decline, raising concerns about grid resilience. Utility-scale battery energy storage systems (BESS)with grid-forming (GFM)inverters offer a promising solution. This paper examines the technical principles, implementation bottlenecks, and project management strategies for deploying black-start functionality in large BESS. Two critical challenges are identified: (i) dispatch coordination and restoration path planning and (ii) grid-connection compatibility and seamless mode switching. Drawing on recent demonstration projects, including Mongolia’s 80 MW/200 MWh BESS (2025), China’s Dalian 200 MW/800 MWh station (2023-2024 black-start trials), and the Qinghai multi- GFM collaborative test (2026), this paper proposes a dual management framework: (1) a joint-drill and protocol-solidification mechanism for dispatch coordination, and (2) a three-level interface management system with clear delivery standards to resolve integration bottlenecks. The findings offer actionable guidelines for project managers, system integrators, and grid operators worldwide. 展开更多
关键词 Black start Utility-scale energy storage Grid-forming control Project management Grid resilience System integration
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新人教版(PEP)教材三年级上册“Start to read”栏目教学策略研究 认领 引用
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作者 周丽梅 《教师》 2026年第14期77-79,共3页
随着基础教育阶段英语课程改革的不断推进,小学英语教材的编写理念与内容设计方面也更科学化与系统化。文章基于新人教版(PEP)三年级上册教材中“Start to read”栏目的具体教学内容,阐述了其在依据主题语境、融合图片信息以及穿插读后... 随着基础教育阶段英语课程改革的不断推进,小学英语教材的编写理念与内容设计方面也更科学化与系统化。文章基于新人教版(PEP)三年级上册教材中“Start to read”栏目的具体教学内容,阐述了其在依据主题语境、融合图片信息以及穿插读后活动三方面的编排特性,并深入分析了教学该栏目过程中面临的现实问题。在此基础上,文章提出了从整体感知语篇内容到聚焦细节观察发现,再到实践应用迁移创新的三步递进式教学策略,旨在为“Start to read”栏目的教学提供可操作的路径。 展开更多
关键词 新人教版(PEP)教材 三年级英语 “Start to read”栏目 教学策略
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2023版Beers标准联合STOPP/START标准对心内科老年患者潜在不适当用药评价分析 认领 引用 被引量：3
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作者 管文婕 陈延杰 +3 位作者 陈尚京 任桂灵 周保柱 朱捷 《安徽医学》 2025年第5期552-557,共6页
目的分析心内科老年患者潜在不适当用药(PIM)情况,为临床药师PIM干预提供依据,为临床医师提供更精准的合理用药指导。方法回顾性分析中国人民解放军联勤保障部队第901医院心内科2022年1~7月收治的261例年龄≥65岁老年患者的住院病历资料... 目的分析心内科老年患者潜在不适当用药(PIM)情况,为临床药师PIM干预提供依据,为临床医师提供更精准的合理用药指导。方法回顾性分析中国人民解放军联勤保障部队第901医院心内科2022年1~7月收治的261例年龄≥65岁老年患者的住院病历资料,采用最新版Beers标准(2023版)、STOPP/START标准(2014版)对入组老年患者潜在用药风险进行评价,分析心内科老年患者的用药现状及PIM发生情况,并采用logistic回归分析法探究PIM的影响因素。结果根据Beers标准,审查出184例患者发生PIM 283次;根据STOPP标准,审查出57例患者发生PIM 69次;根据START标准,审查出90例患者存在122次用药遗漏的PIM情况。logistic回归分析表明,Beers标准提示年龄大、住院时间长、用药种类数多是PIM的危险因素(P<0.05);STOPP/START标准提示年龄大、住院时间长是PIM的危险因素(P<0.05)。结论心内科老年住院患者的PIM发生率较高,使用2种评估标准可全面地筛查出老年患者的PIM,能有效降低药物不良事件的发生,提高老年患者合理用药水平。 展开更多
关键词 老年患者 心内科 潜在不适当用药 Beers标准 STOPP/START标准
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Effect of start cooling temperature on microstructure,crystallographic orientation and ductile-to-brittle transition behavior of high strength steel 认领 引用
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作者 LIU Wen-jian LI Hong-ying +5 位作者 KONG Yao-jie LIU Ji-wen LIU Dan GAO Qing PENG Ning-qi XIONG Xiang-jiang 《Journal of Central South University》 SCIE EI CAS CSCD 2025年第3期776-788,共13页
The ductile-to-brittle transition temperature(DBTT)of high strength steels can be optimized by tailoring microstructure and crystallographic orientation characteristics,where the start cooling temperature plays a key ... The ductile-to-brittle transition temperature(DBTT)of high strength steels can be optimized by tailoring microstructure and crystallographic orientation characteristics,where the start cooling temperature plays a key role.In this work,X70 steels with different start cooling temperatures were prepared through thermo-mechanical control process.The quasi-polygonal ferrite(QF),granular bainite(GB),bainitic ferrite(BF)and martensite-austenite constituents were formed at the start cooling temperatures of 780℃(C1),740℃(C2)and 700℃(C3).As start cooling temperature decreased,the amount of GB decreased,the microstructure of QF and BF increased.Microstructure characteristics of the three samples,such as high-angle grain boundaries(HAGBs),MA constituents and crystallographic orientation,also varied with the start cooling temperatures.C2 sample had the lowest DBTT value(−86℃)for its highest fraction of HAGBs,highest content oforiented grains and lowest content oforiented grains parallel to TD.The high density of{332}and low density of rotated cube{001}textures also contributed to the best impact toughness of C2 sample.In addition,a modified model was used in this paper to quantitatively predict the approximate DBTT value of steels. 展开更多
关键词 X70 steel start cooling temperature ductile-to-brittle transition martensite-austenite islands crystallographic orientation ductile-to-brittle transition temperature(DBTT) prediction model
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基于STOPP/START标准评价医院老年住院患者潜在不适当用药 认领 引用
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作者 吉顺莉 张春燕 +2 位作者 王静 周虹 罗佳 《临床合理用药》 2025年第24期139-142,共4页
目的 回顾性分析评价南通大学附属医院老年住院患者潜在不适当用药(PIM),以促进老年患者的合理用药。方法 选取2018年1—12月于南通大学附属医院老年科治疗后出院的300例年龄≥65岁患者用药情况。以STOPP/START标准(2014版)为评判依据,... 目的 回顾性分析评价南通大学附属医院老年住院患者潜在不适当用药(PIM),以促进老年患者的合理用药。方法 选取2018年1—12月于南通大学附属医院老年科治疗后出院的300例年龄≥65岁患者用药情况。以STOPP/START标准(2014版)为评判依据,分析存在的PIM情况。采用Logistic回归方法分析PIM的危险因素。结果 300例患者中男180例,女120例;年龄(77.8±9.0)岁;住院时间3~92(17.9±16.7)d;用药种类1~59(13.2±10.0)种;患者中临床诊断1~14(4.8±2.9)种,排名前3位分别为高血压病(172例)、糖尿病(99例)、冠心病(81例)。按STOPP标准对处方进行审核,发现58例PIM,包括12个条目,共计81项,其中以苯二氮[艹卓]类为最高(8.67%),非甾体抗炎药用于重度高血压或严重心力衰竭患者(6.67%)次之。Logistic回归分析结果,用药品种数与PIM的发生有关,而年龄、住院时间和疾病种类数则与之无关。根据START标准筛选出95例遗漏处方,包括14个条目,共计232个项。其中遗漏较多的是血管紧张素酶抑制剂、β受体阻滞剂和α1受体阻剂,分别是95例(31.67%)、67例(22.33%)、20例(6.67%)。Logistic回归分析结果显示,年龄和疾病种类数与PIM的发生有关,而性别、用药品种数和住院时间则与之无关。结论 STOPP/START标准可审查出PIM和遗漏处方,应善加利用,尽可能减少PIM的发生。 展开更多
关键词 STOPP/START标准 潜在不适当用药 老年住院患者
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玉米START基因家族的鉴定及表达分析 认领 引用
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作者 常红娟 刘霞 +1 位作者 刘彤彤 王凤茹 《分子植物育种》 CAS 北大核心 2025年第7期2113-2124,共12页
为明确START结构域在调控玉米生长发育中的功能,本研究以玉米START基因家族为研究对象,对其进行了系统进化、理化性质、启动子元件预测等生物信息学分析,通过qPCR分析了ZmPH-START1基因对BR和ABA相关基因表达量的影响。结果表明,玉米ST... 为明确START结构域在调控玉米生长发育中的功能,本研究以玉米START基因家族为研究对象,对其进行了系统进化、理化性质、启动子元件预测等生物信息学分析,通过qPCR分析了ZmPH-START1基因对BR和ABA相关基因表达量的影响。结果表明,玉米START基因家族有33个成员,依据结构域的不同可以分为四个亚家族:第一类亚家族序列中仅含有START结构域,第二类亚家族序列中含有PH、START及DUF1336结构域,第三类亚家族含有START、HD-Zip(HOX-BRLZ)及MEKHLA结构域,第四类亚家族含有START及HD-Zip(HOX-BRLZ)结构域。除ZmPH-START1和仅含START结构域亚家族成员为碱性外,其余均呈酸性,对其启动子元件预测分析显示存在多种与激素响应和胁迫响应相关的顺式作用元件,qPCR结果显示ZmPH-START1基因影响着BR和ABA相关基因的表达水平,推测该基因家族易受到激素信号的调控对植物生长发育起作用,本研究为开展玉米START基因家族对玉米生长发育的功能和作用机制研究提供了参考。 展开更多
关键词 玉米 START结构域 生长发育 生物信息学分析
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Experiments on the Start-Up and Shutdown of a Centrifugal Pump and Performance Prediction 认领 引用
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作者 Yuliang Zhang Zezhou Yang +3 位作者 Lianghuai Tong Yanjuan Zhao Xiaoqi Jia Anda Han 《Fluid Dynamics & Materials Processing》 EI 2025年第4期891-938,共48页
This paper investigates the start-up and shutdown phases of a five-bladed closed-impeller centrifugal pump through experimental analysis,capturing the temporal evolution of its hydraulic performances.The study also pr... This paper investigates the start-up and shutdown phases of a five-bladed closed-impeller centrifugal pump through experimental analysis,capturing the temporal evolution of its hydraulic performances.The study also predicts the transient characteristics of the pump under non-rated operating conditions to assess the accuracy of various machine learning methods in forecasting its instantaneous performance.Results indicate that the pump’s transient behavior in power-frequency mode markedly differs from that in frequency-conversion mode.Specifically,the power-frequency mode achieves steady-state values faster and exhibits smaller fluctuations before stabilization compared to the other mode.During the start-up phase,as the steady-state flow rate increases,inlet and outlet pressures and head also rise,while torque and shaft power decrease,with rotational speed remaining largely unchanged.Conversely,during the shutdown phase,no significant changes were observed in torque,shaft power,or rotational speed.Six machine learning models,including Gaussian Process Regression(GPR),Decision Tree Regression(DTR),and Deep Learning Networks(DLN),demonstrated high accuracy in predicting the hydraulic performance of the centrifugal pump during the start-up and shutdown phases in both power-frequency and frequency-conversion conditions.The findings provide a theoretical foundation for improved prediction of pump hydraulic performance.For instance,when predicting head and flow rate during power-frequency start-up,GPR achieved absolute and relative errors of 0.54 m(7.84%)and 0.21 m3/h(13.57%),respectively,while the Feedforward Neural Network(FNN)reported errors of 0.98 m(8.24%)and 0.10 m3/h(16.71%).By contrast,the Support Vector Machine Regression(SVMR)and Generalized Additive Model(GAM)generally yielded less satisfactory prediction accuracy compared to the other methods. 展开更多
关键词 Centrifugal pumps starting and stopping period power frequency frequency conversion external characteristic machine learning
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Numerical Simulation of Air-Assisted Heating for Cold-Start in Cathode-Open Proton Exchange Membrane Fuel Cells 认领 引用
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作者 Wei Shi Shusheng Xiong +2 位作者 Wei Li Kai Meng Qingsheng Liu 《Energy Engineering》 EI 2025年第9期3507-3523,共17页
In the realm of all-electric aircraft research,the integration of cathode-open proton exchange membrane fuel cells(PEMFC)with lithiumbatteries as a hybrid power source for small to medium-sized unmanned aerial vehicle... In the realm of all-electric aircraft research,the integration of cathode-open proton exchange membrane fuel cells(PEMFC)with lithiumbatteries as a hybrid power source for small to medium-sized unmanned aerial vehicles(UAVs)has garnered significant attention.The PEMFC,serving as the primary energy supply,markedly extends the UAV’s operational endurance.However,due to payload limitations and spatial constraints in the airframe layout of UAVs,the stack requires customized adaptation.Moreover,the implementation of auxiliary systems to facilitate cold starts of the PEMFC under low-temperature conditions is not feasible.Relying solely on thermal insulation measures also proves inadequate to address the challenges posed by complex low-temperature startup scenarios.To overcomethis,our study leverages the UAV’s lithium battery to heat the cathode inlet airflow,aiding the cathode-open PEMFC cold start process.To validate the feasibility of the proposed air-assisted heating strategy during the conceptual design phase,this study develops a transient,non-isothermal 3Dcathode-open PEMF Cunitmodel incorporating cathode air-assisted heating and gas-ice phase change.The model’s accuracy was verified against experimental cold-start data from a stack composed of identical single cells.This computational framework enables quantitative analysis of temperature fields and ice fraction distributions across domains under varying air-assisted heating powers during cold starts.Building upon this model,the study further investigates the improvement in cold start performance by heating the cathode intake air with varying power levels.The results demonstrate that the fuel cell achieves self-startup at temperatures as low as−13℃ under a constant current density of 100mA/cm2 without air-assisted heating.At an ambient temperature of−20℃,a successful start-up can be achieved with a heating power of 0.45 W/cm2.The temperature variation overtime during the cold start process can be represented by a sum of two exponential functions.The air-assisted heating scheme proposed in this study has significantly improved the cold start performance of fuel cells in low-temperature environments.Additionally,it provides critical reference data and validation support for component selection and feasibility assessment of hybrid power systems. 展开更多
关键词 PEMFC cold start numerical modeling air heating
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人工智能在小学英语科普绘本阅读教学中的创新实践——以It Started with a plant为例 认领 引用
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作者 杜欣芮 《启迪》 2025年第30期238-240,共3页
引言小学英语阅读教学是落实英语学科核心素养的必经之路,而科普绘本阅读又是阅读的重中之重。本文通过对多维阅读科普绘本It Started with a plant的教学案例分析,详细探讨了人工智能赋能小学英语绘本教学的应用策略和实际成效。人工... 引言小学英语阅读教学是落实英语学科核心素养的必经之路,而科普绘本阅读又是阅读的重中之重。本文通过对多维阅读科普绘本It Started with a plant的教学案例分析,详细探讨了人工智能赋能小学英语绘本教学的应用策略和实际成效。人工智能的引入,极大地增强了课堂的互动性和趣味性,使学生更深入地理解食物链的逻辑,激发了学习英语的兴趣。人工智能不仅能够为孩子们提供个性化学习体验,还能够极大地提高教学效率和质量。 展开更多
关键词 阅读教学 小学英语 It Started with a plant 科普绘本
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Effects of relaxation time on start-up time for starting flow of Maxwell fluid in a pipe 认领 引用
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作者 Zhen Li Keqin Zhu 《Acta Mechanica Sinica》 SCIE EI CAS 2010年第2期209-215,共7页
Although the analytical solution of the starting flow of Maxwell fluid in a pipe has been derived for a long time,the effect of relaxation timeλon start-up time ts of this flow is still not well understood.Especially... Although the analytical solution of the starting flow of Maxwell fluid in a pipe has been derived for a long time,the effect of relaxation timeλon start-up time ts of this flow is still not well understood.Especially,there exist a series of jumps on the ts-λ.curve.In this paper we introduce a normalized mechanical energy by mode decomposition and mathematical analogy to describe the start-up process.An improved definition of start-up time is presented based on the normalized mechanical energy.It is proved that the ts-λ.curve contains a series of jumps ifλis larger than a critical value.The exact positions of the jumps are determined and the physical reason of the jumps is discussed. 展开更多
关键词 Maxwell fluid Starting flow Relaxation time Start-up time Mechanical energy
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Start of vegetation growing season on the Tibetan Plateau inferred from multiple methods based on GIMMS and SPOT NDVI data 认领 引用 被引量：22
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作者 DING Mingjun LI Lanhui +5 位作者 ZHANG Yili SUN Xiaomin LIU Linshan GAO Jungang WANG Zhaofeng LI Yingnian 《Journal of Geographical Sciences》 SCIE CSCD 2015年第2期131-148,共18页
In this study, we have used four methods to investigate the start of the growing season （SGS） on the Tibetan Plateau （TP） from 1982 to 2012, using Normalized Difference Vegetation Index （NDVI） data obtained from... In this study, we have used four methods to investigate the start of the growing season （SGS） on the Tibetan Plateau （TP） from 1982 to 2012, using Normalized Difference Vegetation Index （NDVI） data obtained from Global Inventory Modeling and Mapping Studies （GIMSS, 1982-2006） and SPOT VEGETATION （SPOT-VGT, 1999-2012）. SGS values esti- mated using the four methods show similar spatial patterns along latitudinal or altitudinal gradients, but with significant variations in the SGS dates. The largest discrepancies are mainly found in the regions with the highest or the lowest vegetation coverage. Between 1982 and 1998, the SGS values derived from the four methods all display an advancing trend, however, according to the more recent SPOT VGT data （1999-2012）, there is no continu- ously advancing trend of SGS on the TP. Analysis of the correlation between the SGS values derived from GIMMS and SPOT between 1999 and 2006 demonstrates consistency in the tendency with regard both to the data sources and to the four analysis methods used. Com- pared with other methods, the greatest consistency between the in situ data and the SGS values retrieved is obtained with Method 3 （Threshold of NDVI ratio）. To avoid error, in a vast region with diverse vegetation types and physical environments, it is critical to know the seasonal change characteristics of the different vegetation types, particularly in areas with sparse grassland or evergreen forest. 展开更多
关键词 phenology NDVI start of vegetation growing season method Tibetan Plateau
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Beers标准联合STOPP/START准则评价我院内科老年住院患者潜在不适当用药 认领 引用 被引量：27
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作者 周海峰 沈杰 +2 位作者 纪芳 张云轩 张敏 《中国药房》 CAS 北大核心 2016年第23期3212-3214,共3页
目的:提高合理用药水平,减少潜在不适当用药。方法:以Beers(2012年版)标准联合STOPP/START准则对我院内科700例老年住院患者用药潜在风险进行评价。结果:700例患者平均年龄(76.3±7.2)岁,平均用药(12.1±4.9)种,有144例(20.6%)... 目的:提高合理用药水平,减少潜在不适当用药。方法:以Beers(2012年版)标准联合STOPP/START准则对我院内科700例老年住院患者用药潜在风险进行评价。结果:700例患者平均年龄(76.3±7.2)岁,平均用药(12.1±4.9)种,有144例(20.6%)存在潜在不适当用药;共计存在潜在不适当用药220例次,其中Beers药物相关117例次、Beers疾病相关22例次、STOPP用药9例次、START处方遗漏72例次。Beers审核结果中潜在不适当用药频度最高的药物为苯二氮类,STOPP审核结果频度最高的是有痛风史的患者使用噻嗪类利尿药;START处方遗漏频度最高的是2型糖尿病未接受二甲双胍治疗和糖尿病有心血管风险未接受抗血小板治疗。结论:我院老年住院患者潜在不适当用药情况较严重,应采取多种措施预防其不合理用药。 展开更多
关键词 Beers标准 STOPP/START准则 老年患者 潜在不适当用药
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Beers标准、STOPP/START标准及中国PIM初级判断标准评价某院心血管内科医嘱的对比研究 认领 引用 被引量：24
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作者 何梅 邵鑫 +2 位作者 赵曜 李胜前 张晓钰 《中国医院药学杂志》 CAS 北大核心 2018年第7期781-784,791,共4页
目的:比较2015年版Beers标准,2014年版STOPP/START标准及中国潜在不合理用药(PIM)初级判断标准的异同,为完善中国标准提供参考。方法:回顾性分析2017年1-3月于某三甲综合医院心血管内科住院的老年患者医嘱,以前述3个标准为评价依据进行... 目的:比较2015年版Beers标准,2014年版STOPP/START标准及中国潜在不合理用药(PIM)初级判断标准的异同,为完善中国标准提供参考。方法:回顾性分析2017年1-3月于某三甲综合医院心血管内科住院的老年患者医嘱,以前述3个标准为评价依据进行对比分析,用SPSS13.0进行数据统计分析。结果:纳入患者417例依照中国PIM初级判断标准,审查出潜在不适当用药有184例(44.1%),且列出了药物风险点;依照Beers标准,除潜在不适当用药230例(55.2%)外,还审查出应谨慎使用药物225例(54.0%),非抗感染药物间相互作用6例(0.2%)及因肾功不全使用非抗感染药物的警示病例60例(14.4%)三部分内容,且每个推荐条目都注明相应的证据分级和推荐强度。STOPP/START标准按生理系统分类,除潜在不适当用药195例(46.8%)外,还审查出处方遗漏97例(23.3%)。3个标准均未涉及评价中成药。结论:三个标准在适用对象及关注点上相似,但在编排及内容上有区别,在潜在不合理用药的评判中中国标准缺乏药物相互作用、重复用药及中成药潜在不适当用药条目。此外,中国标准亦缺乏Beers标准的谨慎使用药物及STOPP/START标准的处方遗漏医嘱。同时,该院心血管内科老年住院患者不适当用药情况较严重且用药品种偏多,合理用药水平还有待提高。 展开更多
关键词 Beers标准 STOPP/START标准 中国PIM初级判断标准 老年患者 潜在不合理用药
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