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轮胎阶梯式直压硫化内模具的运动学仿真研究

橡胶工业 2024年第1期71卷 58-62页

作者：涂玉祥靳晓哲杨卫民何雪涛阎华谭晶焦志伟北京化工大学机电工程学院北京100029 轮胎设计与制造工艺国家工程实验室北京100029

对225/40R18轮胎的阶梯式直压硫化内模具(简称内模具)进行运动学仿真研究。通过设定连杆和运动副以及用STEP函数控制内模具的运动,进行仿真分析得到了在活塞外杆、活塞内杆、宽鼓瓦、窄鼓瓦中心位置设置的观测点的位移情况。结果表明,... 详细信息

对225/40R18轮胎的阶梯式直压硫化内模具(简称内模具)进行运动学仿真研究。通过设定连杆和运动副以及用STEP函数控制内模具的运动,进行仿真分析得到了在活塞外杆、活塞内杆、宽鼓瓦、窄鼓瓦中心位置设置的观测点的位移情况。结果表明,阶梯式内模具的运动平稳、连续,且不会发生干涉。

关键词：轮胎阶梯式直压硫化内模具模具设计运动学仿真

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High-Efficiency Rectifier for Wireless Energy Harvesting Based on Double Branch Structure

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Journal of Donghua University(English Edition) 2023年第4期40卷 438-445页

作者：崔恒荣焦劲华杨威荆玉香 College of Information Science and Technology Donghua UniversityShanghai 201620China

A rectifier circuit for wireless energy harvesting(WEH) with a wide input power range is proposed in this paper. We build up accurate models of the diodes to improve the accuracy of the design of the rectifier. Due to the nonlinear characteristics of the diodes, a new band-stop structure is introduced to reduce the imaginary part impedance and suppress harmonics. A novel structure with double branches and an optimized λ/4 microstrip line is proposed to realize the power division ratio adjustment by the input power automatically. The proposed two branches can satisfy the two cases with input power of-20 dBm to 0 dBm and 0 dBm to 15 dBm, respectively. Here, dBm = 10 log(P mW), and P represents power. An impedance compression network(ICN) is correspondingly designed to maintain the input impedance stability over the wide input power range. A rectifier that works at 2.45 GHz is implemented. The measured results show that the highest efficiency can reach 51.5% at the output power of 0 dBm and higher than 40% at the input power of-5 dBm to 12 dBm.

关键词： diode modeling rectifier circuit impedance compression network power division strategy

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复合材料波纹腹板梁坠撞试验与数值模拟

南京航空航天大学学报 2023年第1期55卷 51-57页

作者：李姣于健李宇翔航空工业成都飞机工业(集团)有限责任公司成都610091 南京航空航天大学通用航空与飞行学院南京211106

为了探究复合材料波纹腹板梁在坠撞过程中的吸能性能,对复合材料波纹腹板梁试验件进行了动态冲击压溃试验研究,得到了试验件的损伤破坏形貌以及载荷和能量的历程曲线。基于ABAQUS/Explicit平台二次开发得到了模拟复合材料波纹腹板梁冲... 详细信息

为了探究复合材料波纹腹板梁在坠撞过程中的吸能性能,对复合材料波纹腹板梁试验件进行了动态冲击压溃试验研究,得到了试验件的损伤破坏形貌以及载荷和能量的历程曲线。基于ABAQUS/Explicit平台二次开发得到了模拟复合材料波纹腹板梁冲击压溃过程的仿真分析模型,模型采用了改进的Hashin损伤判定准则和Choi-Chang准则综合判断单元失效,并结合Cohesive界面单元,可较为真实地反映所研究复合材料层合结构的各向异性和渐进损伤特性。通过数值模拟得到了能量评估参数比吸能(Specific energy absorption,SEA)和平均压溃载荷,与试验结果进行了对比分析。基于仿真分析模型,本文进一步研究了不同波数的复合材料波纹腹板梁的吸能能力。数值模拟结果表明:波纹腹板梁在冲击载荷作用下发生了渐进压溃失效;平均压溃载荷的相对误差较小,验证了模型的有效性;在腹板单波长度不变的情况下,波纹腹板梁的长度对抗冲击吸能的影响较大。当波纹腹板梁长度较小时,结构容易失稳,无法有效地吸收能量。

关键词：波纹腹板梁层合板坠撞试验冲击压溃有限元法

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管束排列及管间距对换热器传热性能的影响

石油学报（石油加工） 2013年第5期29卷 836-843页

作者：焦凤邓先和孙大力洪宇翔华南理工大学化学与化工学院广东广州510640

通过改变圆形翅片管换热器管束排列及管间距的传热性能实验,得到雷诺数(Re)、纵向管间距(Sl)及管束排列方式对圆形翅片管换热器传热性能的影响,再利用数值模拟方法分析这3个因素影响的原因。结果表明,圆形翅片管换热器的努赛尔数(Nu)及... 详细信息

通过改变圆形翅片管换热器管束排列及管间距的传热性能实验,得到雷诺数(Re)、纵向管间距(Sl)及管束排列方式对圆形翅片管换热器传热性能的影响,再利用数值模拟方法分析这3个因素影响的原因。结果表明,圆形翅片管换热器的努赛尔数(Nu)及阻力系数(f)均随Re的增加而增加,且增加趋势逐渐下降。增大Sl可提高顺排圆形翅片管换热器的传热性能,但是提高幅度随Sl的增加而减小,在Sl为110mm时换热效果最好;增大Sl反而会降低叉排圆形翅片管换热器的传热性能,其换热效果在Sl为66mm时最好。相对于顺排方式,叉排圆形翅片管换热器的换热效果更好。速度场与温度场间的协同角度大小、回流区面积及尾流涡尺度大小与换热器传热性能的提高有关,可以从这3个方面进行分析,以寻找改善换热器结构的途径。

关键词：圆形翅片纵向管间距场协同回流区强化传热

Large circuit models: opportunities and challenges

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Science China(Information Sciences) 2024年第10期 25-66页

作者： Lei CHEN Yiqi CHEN Zhufei CHU Wenji FANG Tsung-Yi HO Ru HUANG Yu HUANG Sadaf KHAN Min LI Xingquan LI Yu LI Yun LIANG Jinwei LIU Yi LIU Yibo LIN Guojie LUO Hongyang PAN Zhengyuan SHI Guangyu SUN Dimitrios TSARAS Runsheng WANG Ziyi WANG Xinming WEI Zhiyao XIE Qiang XU Chenhao XUE Junchi YAN Jun YANG Bei YU Mingxuan YUAN Evangeline F.Y.YOUNG Xuan ZENG Haoyi ZHANG Zuodong ZHANG yuxiang ZHAO Hui-Ling ZHEN Ziyang ZHENG Binwu ZHU Keren ZHU Sunan ZOU Huawei Noah’s Ark Lab School of Integrated Circuits Peking University Faculty of Electrical Engineering and Computer Science Ningbo University Department of Electronic and Computer Engineering Hong Kong University of Science and Technology Department of Computer Science and Engineering The Chinese University of Hong Kong School of Integrated Circuits Southeast University Huawei HiSilicon Peng Cheng Laboratory School of Computer Science Peking University School of Microelectronics State Key Laboratory of Integrated Chips and System Fudan University School of Artificial Intelligence Shanghai Jiao Tong University

Within the electronic design automation(EDA) domain, artificial intelligence(AI)-driven solutions have emerged as formidable tools, yet they typically augment rather than redefine existing methodologies. These solutions often repurpose deep learning models from other domains, such as vision, text, and graph analytics, applying them to circuit design without tailoring to the unique complexities of electronic circuits. Such an “AI4EDA” approach falls short of achieving a holistic design synthesis and understanding,overlooking the intricate interplay of electrical, logical, and physical facets of circuit data. This study argues for a paradigm shift from AI4EDA towards AI-rooted EDA from the ground up, integrating AI at the core of the design process. Pivotal to this vision is the development of a multimodal circuit representation learning technique, poised to provide a comprehensive understanding by harmonizing and extracting insights from varied data sources, such as functional specifications, register-transfer level(RTL) designs, circuit netlists,and physical layouts. We champion the creation of large circuit models(LCMs) that are inherently multimodal, crafted to decode and express the rich semantics and structures of circuit data, thus fostering more resilient, efficient, and inventive design methodologies. Embracing this AI-rooted philosophy, we foresee a trajectory that transcends the current innovation plateau in EDA, igniting a profound “shift-left” in electronic design methodology. The envisioned advancements herald not just an evolution of existing EDA tools but a revolution, giving rise to novel instruments of design-tools that promise to radically enhance design productivity and inaugurate a new epoch where the optimization of circuit performance, power, and area(PPA) is achieved not incrementally, but through leaps that redefine the benchmarks of electronic systems' capabilities.

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5例直接口服抗凝药治疗非瓣膜性房颤患者左心耳血栓的用药分析

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药学与临床研究 2024年第2期32卷 165-168页

作者：侯凯费禹翔李平张金莲王芳杨宇上海交通大学医学院附属新华医院临床药学部上海200092 东南大学附属中大医院药学部南京210009 南京市第一医院药学部南京210006

临床药师参与5例非瓣膜性房颤合并左心耳血栓患者的抗凝治疗管理,通过患者临床表现、食道超声心动图评估药物的安全性与疗效,分析利伐沙班和艾多沙班对于协助纤溶系统溶解左心耳血栓的效果与差异。结果显示两种药物均能不同程度地促进... 详细信息

临床药师参与5例非瓣膜性房颤合并左心耳血栓患者的抗凝治疗管理,通过患者临床表现、食道超声心动图评估药物的安全性与疗效,分析利伐沙班和艾多沙班对于协助纤溶系统溶解左心耳血栓的效果与差异。结果显示两种药物均能不同程度地促进血栓消退,血栓消退的时间可能与血栓面积以及患者心功能相关。术后临床药师结合患者肾功能与合并用药情况,为患者制定安全、有效、个体化的抗凝方案。

关键词：临床药师非瓣膜性房颤左心耳血栓利伐沙班艾多沙班

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长链烷基萘合成工艺研究

石油炼制与化工 2009年第3期40卷 22-25页

作者：梁宇翔焦广文石油化工科学研究院北京100083 南阳石蜡精细化工厂

以二氧化硅负载磷钨杂多酸为催化剂,以长链α-烯烃为烷基化试剂和萘发生烷基化反应,考察了不同烯烃、不同反应条件对产品收率和产品质量的影响。研究结果表明,采用1-十六烯作为烷基化试剂,在催化剂加入量(w)为4%、反应温度130℃、烯烃... 详细信息

以二氧化硅负载磷钨杂多酸为催化剂,以长链α-烯烃为烷基化试剂和萘发生烷基化反应,考察了不同烯烃、不同反应条件对产品收率和产品质量的影响。研究结果表明,采用1-十六烯作为烷基化试剂,在催化剂加入量(w)为4%、反应温度130℃、烯烃与萘摩尔比为1.35、反应时间50 min的条件下,产品收率为88.2%,DSC(O2)氧化分解温度为225.3℃,粘度指数为104,倾点为-27℃。

关键词：萘烯烃烷基化粘度指数反应条件

Thermoelastic Dissipation in Diamond Micro Hemispherical Shell Resonators

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Journal of Shanghai jiaotong university(Science) 2020年第3期25卷 281-287页

作者： FENG Jun ZHANG Weiping LIU Zhaoyang GU Liutao CHENG yuxiang National Key Laboratory of Science and Technology on Micro/Nano Fabrication Shanghai Jiao Tong UniversityShanghai 200240China Department of Micro/Nano Electronics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Aerospace Control Technology Institute Shanghai 200233China

Maximizing quality factor (Q) is essential to improve the performance of micro hemispherical shell resonators (μHSRs) which can be used in microelectromechanical system (MEMS) gyroscopes to measure angular *** energy dissipation mechanisms limit Q,where thermoelastic dissipation (TED) is the major one and studied in this *** coupled thermo-mechanical equations for calculating TED are formulated,and then temperature distribution in a deformed μHSR and its quality factor related to TED (QTED) are obtained by solving the equations through a finite-element method (FEM).It has been found that different fabrication process conditions can obtain various geometrical parameters in our previous *** order to provide guidelines for the design and fabrication of μHSRs,the effects of their geometry on resonant frequency (f0) and QTED are *** change of anchor height and small enough anchor radius have no effect on both f0 and QTED,but the shell size including its radius,thickness and height has significant impact on f0 and *** is found that whether a μHSR has lower f0 and higher QTED or higher f0 and higher QTED can be achieved by changing these geometrical *** results presented in this paper can also be applied to other similar resonators.

关键词： microelectromechanical system(MEMS) diamond hemispherical shell resonators quality factor thermoelastic dissipation(TED)

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X80管线钢夹杂物控制工艺的研究

特殊钢 2011年第1期32卷 36-39页

作者：蒋育翔焦兴利北京科技大学经济管理学院北京100083 马钢股份有限公司马鞍山243000

X80微合金化管线钢冶炼的工艺流程为300 t顶底复吹转炉-钢包吹氩微合金化-LF-RH。通过转炉气动挡渣法控制出钢下渣量≤4 kg/t;钢包顶底吹氩搅拌6 min铝粒脱氧;控制LF顶渣CaO/Al_2O_3=1.7～1.9,碱度(CaO/SiO_2)=4.5～6,(FeO+MnO)≤1.0%;R... 详细信息

X80微合金化管线钢冶炼的工艺流程为300 t顶底复吹转炉-钢包吹氩微合金化-LF-RH。通过转炉气动挡渣法控制出钢下渣量≤4 kg/t;钢包顶底吹氩搅拌6 min铝粒脱氧;控制LF顶渣CaO/Al_2O_3=1.7～1.9,碱度(CaO/SiO_2)=4.5～6,(FeO+MnO)≤1.0%;RH喂FeCa线0.8 kg/t,使T[O]达到13×10^(-6),夹杂物尺寸≤10μm,≤5μm夹杂物占98.93%,钢中Al_2O_3尖晶石夹杂物转变为CaO-MgO-Al_2O_3系三元夹杂。分析了冶炼过程夹杂物数量、尺寸形态和组成,得出管线钢夹杂物变性的规律。

关键词：管线钢转炉-钢包吹氩-LF-RH工艺夹杂物控制