摘要：Single cell temperature difference of lithium-ion battery(LIB) module will significantly affect the safety and cycle life of the battery. The reciprocating air-flow module created by a periodic reversal of the air flow was investigated in an effort to mitigate the inherent temperature gradient problem of the conventional battery system with a unidirectional coolant flow with computational fluid dynamics(CFD). Orthogonal experiment and optimization design method based on computational fluid dynamics virtual experiments were developed. A set of optimized design factors for the cooling of reciprocating air flow of LIB thermal management was determined. The simulation experiments show that the reciprocating flow can achieve good heat dissipation, reduce the temperature difference, improve the temperature homogeneity and effectively lower the maximal temperature of the modular battery. The reciprocating flow improves the safety, long-term performance and life span of LIB.

摘要：本文通过人工神经网络方法实现多次搭接激光冲击作用下材料残余应力与显微硬度的预测。以镍基粉末冶金高温合金FGH95为实验材料,基于正交实验设计的思路,确定了多次搭接激光冲击强化的实验参数。利用X射线应力测量仪和显微硬度计分别测量了实验试件激光冲击强化处理前后的残余应力和显微硬度分布,并对残余应力和显微硬度变化规律进行了简要分析。构建了4层网络结构(4-N-(N-1)-2)的人工神经网络预测模型,其中输入为激光能量、光斑搭接率、冲击次数和深度,输出为残余应力和显微硬度。对不同网络结构的预测性能进行了比较和分析。在最优的模型下(网络结构为4-7-6-2),预测值与实验值十分吻合,预测效果极佳。此外,基于人工神经网络的方法,还研究了激光冲击强化工艺参数对材料响应的影响。研究表明,在实验数据较为缺乏的情况下,人工神经网络是预测多次搭接激光冲击作用下材料残余应力和显微硬度的有效方法。

摘要：随着工业过程复杂程度的不断提高,高维工业数据呈现出很强的非线性,给工业过程的故障诊断带来了相当大的挑战。为了有效提取对故障诊断至关重要的深层特征,首先,设计了稀疏高斯特征提取器(SGFE)来学习非线性映射,该映射能够将原始数据投影到具有故障标签维度的特征空间中。特征空间由故障类别标签的one-hot编码作为正交基构成。这样,SGFE可以从原始数据中逐步学习到与故障标签相关的深度稀疏高斯特征。然后,在特征空间中,设计了稀疏高斯(SG)损失函数,将特征约束为多个稀疏多元高斯分布。稀疏的高斯特征在特征空间是线性可分的,这有利于提高下游故障分类任务的性能。最后,对本文所提出的SGFE算法的可行性和实用性分别通过手写数字(MNIST)数据集和田纳西-伊士曼(TE)过程进行了验证。

摘要：Based on rational behavior model of three layers, a tracking control system is designed for straight line tracking which is commonly used in underwater survey missions. An intelligent PID control law implemented as planning level during the control system using transverse deviation is came up with. Continuous tracking of path expressed by a point sequence can be realized by the law. Firstly, a path tracking control system based on rational behavior model of three layers is designed, mainly satisfying the needs of underactuated AUV. Since there is no need to perform spatially coupled maneuvers, the 3D path tracking control is decoupled into planar 2D path tracking and depth or height tracking separately. Secondly, planar path tracking controller is introduced. For the reason that more attention is paid to comparing with vertical position control, transverse deviation in analytical form is derived. According to the Lyapunov direct theory, control law is designed using discrete PID algorithm whose parameters obey adaptive fuzzy adjustment. Reference heading angle is given as an output of the guidance controller conducted by lateral deviation together with its derivative. For the purpose of improving control quality and facilitating parameter modifying, data normalize modules based on Sigmoid function are applied to input-output data manipulation. Lastly, a sequence of experiments was carried out successfully, including tests in Longfeng lake and at the Yellow sea. In most challenging sea conditions, tracking errors of straight line are below 2 m in general. The results show that AUV is able to compensate the disturbance brought by sea current. The provided test results demonstrate that the designed guidance controller guarantees stably and accurately straight route tracking. Besides, the proposed control system is accessible for continuous comb-shaped path tracking in region searching.

摘要：千米级高铁悬索桥的风致抖振问题严重影响高铁列车的行车安全性与行车舒适度。为深入研究高铁悬索桥的抖振响应,以首座大跨高铁悬索桥——五峰山大桥为例,采用谐波合成法模拟了全桥风场,进而基于有限元方法,分析了结构参数与风环境参数对高铁悬索桥抖振性能的影响。结果表明,在改变主梁质量时,桥梁竖向响应的敏感程度较横向和扭转响应更为敏感;提升主梁的整体刚度、减小主缆的矢跨比都有助于减小悬索桥的抖振响应;横、竖向脉动风谱和风场空间相干函数是影响结构抖振响应的关键因素,因此在抗风设计阶段选取合适的风场参数至关重要。分析结果可为大跨高铁悬索桥的抗风分析及结构、脉动风场参数的选取提供参考。

摘要：Finite element method was performed to investigate the influences of beam stiffness,foundation width and cushion thickness on the bearing capacity of beam foundation on underlying weak laminated *** comparison between numerical results and results from field test including plate-bearing test and foundation settlement observation shows reasonable *** to the numerical results,the beam width,length,cross section and cushion thickness were *** results show that the stresses in subgrade soil decrease greatly with increasing the cushion thickness and width of ***,the foundation settlement and influencing depth of displacement also increase correspondingly under conditions of relatively thinner cushion *** the foundations on underlying weak layer,increasing foundation width merely might be inadequate for improving the bearing capacity,and the appropriate width and cushion thickness depend on the response of subgrade.A comparison between rigid and flexible beams was also *** influence of a flexible beam foundation on subgrade is relatively smaller under the same loading conditions,and the flexible beam foundation appears more adaptable to various *** proposed flexible beam foundation was adopted in *** to the calculation results,beam width of 2.4 m and cushion thickness of 0.8 m are proposed,and a flexible beam foundation is applied in the optimized design,which is confirmed reasonable by the actual engineering.

摘要：为了在一个试件中同时测量纯Ⅰ型和Ⅱ型裂纹的动态起裂韧度,设计了一种大尺寸双裂纹凹凸板试件,利用落锤板冲击装置开展不同加载率的落锤冲击实验。采用高精度应变片测量冲击载荷和裂纹萌生时间。采用动态有限差分程序AUTODYN建立相应的数值模型,利用试验-数值方法确定裂纹的动态起裂韧度。实验和数值研究表明,双裂纹凹凸板试样适合用于同时测量纯Ⅰ型和Ⅱ型裂纹的动态起裂韧度;动态起裂韧度随着加载率的增加而增加,裂纹萌生时间随着加载率的增加而减小;在相同加载率下,纯Ⅱ型裂纹的起裂韧度大约是纯Ⅰ型裂纹的0.5倍;随着试样底部预制裂缝长度从20 mm增加到100 mm,纯Ⅰ型裂纹的动态起裂韧度逐渐降低,表明底部预制裂纹长度越长Ⅰ型裂纹越容易起裂,但纯Ⅱ型裂纹的动态起裂韧度变化不大。

摘要：To improve the computational efficiency of the reliability-based design optimization(RBDO) of flexible mechanism, particle swarm optimization-advanced extremum response surface method(PSO-AERSM) was proposed by integrating particle swarm optimization(PSO) algorithm and advanced extremum response surface method(AERSM). Firstly, the AERSM was developed and its mathematical model was established based on artificial neural network, and the PSO algorithm was investigated. And then the RBDO model of flexible mechanism was presented based on AERSM and PSO. Finally, regarding cross-sectional area as design variable, the reliability optimization of flexible mechanism was implemented subject to reliability degree and uncertainties based on the proposed approach. The optimization results show that the cross-section sizes obviously reduce by 22.96 mm^2 while keeping reliability degree. Through the comparison of methods, it is demonstrated that the AERSM holds high computational efficiency while keeping computational precision for the RBDO of flexible mechanism, and PSO algorithm minimizes the response of the objective function. The efforts of this work provide a useful sight for the reliability optimization of flexible mechanism, and enrich and develop the reliability theory as well.

摘要：为了改进单身者的设计和计算的可靠性，堆在下面联合了垂直、侧面的负担，答案基于路基反应方法，最终的土壤抵抗在被考虑被介绍，路基反应的系数被假定是一个常数。相应计算节目用 FORTRAN 语言被开发。在获得的答案和模型测试结果之间的比较被做显示出获得的答案的有效性。，计算结果显示有垂直、侧面的负担和上面的堆积长度的增加的最大的侧面的排水量和弯曲时刻增加磨擦了作为堆积僵硬，路基反应的系数和土壤增加的让步的排水量减少。堆积头条件控制堆积回答，这也被显示出，垂直负担可以引起不稳定性问题到堆积。一般来说，建议方法能被采用计算堆积偏转的大小的堆积回答独立人士。

摘要：拓宽材料对光子的吸收是利用太阳光能的关键.然而,要平衡电极材料对光的最大化吸收与存储是当前光电极材料的设计难点.本文报道了一种具有丰富硫空位的Cu_(2)S/CuCl异质阵列材料,该材料中CuCl与硫空位的存在增加了其对光子的捕获与转化.同时,Cu_(2)S/CuCl异质结增加了材料的导电性能,促进了电子的传输效率.当作为赝电容的电极材料时,该Cu_(2)S/CuCl双功能材料的光照下容量提升比率高达35%.同时,由该材料制成的非对称电容器循环测试6000次之后的面积比容量可依旧维持在670 mF cm^(-2).该Cu_(2)S/CuCl材料具有优异的光电化学性能,在下一代光辅助充电储能器件的应用领域展示出巨大前景.