摘要：This study investigates the influence of different pantograph parameters and train length on the aerodynamic drag of high-speed train by the delayed detached eddy simulation(DDES) method. The train geometry considered is the high-speed train with pantographs, and the different versions have 3, 5, 8, 10, 12, 16 and 17 cars. The numerical results are verified by the wind tunnel test with 3.6% difference. The influences of the number of cars and the position, quantity and configuration of pantographs on flow field around high-speed train and wake vortices are analyzed. The aerodynamic drag of middle cars gradually decreases along the flow direction. The aerodynamic drag of pantographs decreases with its backward shift, and that of the first pantograph decreases significantly. As the number of pantographs increases, its effect on the aerodynamic drag decrease of rear cars is more significant. The engineering application equation for the aerodynamic drag of high-speed train with pantographs is proposed. For the 10-car and 17-car train, the differences of total aerodynamic drag between the equation and the simulation results are 1.2% and 0.4%, respectively. The equation generalized in this study could well guide the design phase of high-speed train.

摘要：针对智能车辆的局部规划与路径跟踪的协同控制问题,提出了一种基于改进粒子群优化(IPSO)的模型预测控制(MPC)方法。首先将模型预测控制与人工势场(APF)相结合,将时变安全约束作为排斥力的范围和非对称的车道势场函数,通过将时变安全约束视为排斥力的范围和非对称车道势场函数来获得无碰撞路径,在此基础上,将APF与IPSO-MPC相结合,采用伪速度规划算法来处理交通灯和运动障碍的约束,从而有效地解决了路径优化问题。仿真结果验证了该算法的有效性,与一般算法相比具有明显的优越性。

摘要：船用柴油机在线诊断和监测对于保障船舶安全航行具有非常重要的作用。经验法和建立数学模型的方法在实际应用中受到非常大的限制,本文提出一种基于振动信号分析的船用柴油机故障诊断系统,分析了柴油机的基本结构和工作流程,对柴油机的不同故障振动信号特征进行分析,在此基础上设计了故障诊断系统的结构,包括振动信号采集、特征提取以及故障诊断模块,通过将柴油机历史振动数据和故障类型建立映射,并基于柴油机振动信号特征使用故障诊断模型输出诊断结果。

摘要：阐述高支模技术在土建施工中的应用要点,并结合某房建工程案例,通过项目施工前期准备阶段、立杆及其他杆件、剪刀撑施工、周边拉结、梁/柱模版安装、模板拆除等具体施工技术要点对高支模技术在房屋土建施工中的具体应用进行探析。研究表明,在房屋土建施工中应用高支模施工技术能够提高房屋建设工程的施工效率及施工质量,对房屋建设工程具有应用价值。

摘要：The spinodal decomposition method emerges as a promising methodology,showcasing its potential in exploring the design space for metamaterial ***,spinodal structures design is still largely limited to regular structures,due to their relatively easy parameterization and *** predicting the mechanical properties of 3D spinodal membrane structure remains a challenge,given that the features of the membrane necessitate adaptive mesh through the modelling *** paper proposes an integrated approach for morphological design with customized mechanical properties,incorporating the spinodal decomposition method and adaptive coarse-grained modeling,which can produce various morphologies such as lamellar,columnar,and cubic ***-periodic parameterβand orientational parameterΘ(θ_(1),θ_(2),θ_(3))are identified to achieve the optimal goal of anisotropic mechanical *** analysis is conducted to reveal the correlation between the customized spinodal structure and mechanical *** work provides an integrated approach for morphological variation and tuning mechanical properties,paving the way for the design and development of customized functional materials similar to 3D spinodal membrane structures.

摘要：α-Diimide catalysts have attracted widespread attention due to their unique chain walking characteristics.A series ofα-diimide nickel/palladium catalysts with different electronic effects and steric hindrances were designed and synthesized for olefin *** this work,we synthesized a series of asymmetricα-diimide nickel complexes with different steric hindrances and used them for ethylene *** nickel catalysts have high ethylene polymerization activity,up to 6.51×10^(6)g·mol^(−1)·h^(−1),and the prepared polyethylene has a moderate melting point and high molecular weight(up to 38.2×10^(4)g·mol^(−1)),with a branching density distribution between 7 and 94 branches per 1000 *** importantly,the polyethylene prepared by these catalysts exhibits excellent tensile properties,with strain and stress reaching 800%and 30 MPa,respectively.

摘要：针对自闭症儿童社交与情绪障碍问题,设计了2款具备距离监测与辅助提示功能的自闭症儿童智能服装。首先,采用问卷调查与实地访谈等方法,归纳出自闭症儿童在穿戴、感统、心理认同3个方面的服装需求;其次,采用超声波距离传感器技术实现社交距离监测;再次,采用气动柔性气囊及可加热碳纤维模拟中医推拿治疗自闭症手法,加热加压刺激手腕部穴位,达到一定的干预和辅助提示患者的目标。研究结果表明:选用的超声波传感器精度高,形状小巧且耐脏污,将其嵌入服装中可有效识别0.2~3 m范围内的社交距离;通过柔性气囊的充气加压可对手腕部穴位产生7.90 kPa的服装压,有助于缓解患者情绪焦虑等症状;智能服装廓形设计采用H/A型,开合方式选用拉链,色彩选用冷色调,口袋设计为几何图形,面料设计兼具舒适性与功能性,符合自闭症儿童服装实际穿着需求。

摘要：在当前,老旧小区改造在时代发展中成为一个新的发展趋势,也是一项惠民的德政工程,其意义在于提高居民的居住环境品质、改善环境面貌和形象。本次设计课题选取社会改造性设计,地址位于天津市红桥区西青道9号的仁爱花园社区改造性设计,改造目的在于能够提高老旧社区的居住环境质量,其中包括解决安全隐患排查、环境优化、适老化人性化设计、添加文化元素融入生活等等。在特殊的文化背景下,尊重周围环境的文化,注重设计的当地城市或民俗文化的融入成为设计师重中之重的选择。设计出具有人情味的居民居住环境,可以增加吸引力和包容性。

摘要：辽瓷盘口穿带瓶设计的精髓在于其科学合理的功用契合了游牧迁徙的需求。基于翔实的历史文献资料与切身实地考察,从存蓄之易、提拎之利、握持之便、便携之需等主要功能视角切入,探求其设计优势与功用价值;并从游牧属性、科学理性、区域特性等鲜明的设计特色与制作技艺角度进行解读。以求在传承辽瓷盘口穿带瓶设计精髓的同时为现代设计艺术提供启迪与借鉴。

摘要：科学类通识课程是高校通识教育中的重要组成部分。本文介绍了清华大学“生物钟与健康”科学类通识课程的建设情况,从课程建设的必要性出发,介绍课程的教学内容设计和评价标准,分析课程开课情况,并对未来课程规划进行讨论。课程已开设3个学期,选课学生已覆盖了全校27个院系,学生评教成绩优异。通过课程学习,学生自述生活习惯有明显改善,对生物学研究的思维方式和方法的理解有显著提升;课程在教学内容和教学方法上有关键创新点。本门课程建设的思路和方法,对高校科学类通识课程建设具有借鉴意义。