摘要：Axial compression tests were conducted on AZ31 B magnesium and A6063 aluminum thin-walled square tubes with varied lengths and induced features at different compression rates. In compression, the magnesium tubes exhibited a "local buckling and fracture" mode, with three fracture patterns, i.e."horizontal","double-oblique", and "spiral" fractures. In general, the magnesium tube showed an inferior crashworthiness to the aluminum square tube. In addition, the effects of L/W ratio, strain rate and induced features on the crashworthiness of thin-walled square tubes were investigated. With an increase in the L/W ratio(L and W represent the tube length and width, respectively) from 1 to 4, the maximal force and global specific energy absorption decreased in a power-law trend for the magnesium tubes,while they remained approximately constant for the aluminum tubes. Furthermore, as the compression rate increased from 5×10-5 to 10 m/s, the primary crashworthiness parameters of the magnesium tubes increased in an approximately exponential manner,while for the aluminum tubes,they changed slightly. Finally,the involved induced features were proven to be not an effective method to improve the specific energy absorption of magnesium tubes, thus, more trigger types,locations,and sizes will be evaluated in future to improve the energy-absorption ability.

摘要：精准检测棉花中混杂的小型异纤是保障纱线与织物质量的基础和关键。针对现有算法在棉花小型异纤检测中存在的漏检率高、网络结构复杂等问题,提出一种基于卷积神经网络轻量化的改进单步多框检测器(SSD)的棉花异纤检测方法。首先,通过引入深度可分离卷积、倒残差结构等创新性设计,将SSD算法中原有骨干特征提取网络VGGNet16替换为MobileNetv2网络;然后,对于SSD算法中生成的候选框尺寸与棉花异纤大小不匹配导致棉花背景占比过高,从而引起正负样本不均衡的问题,采用K-means++算法对棉花异纤尺寸进行聚类分析,根据聚类结果修正候选框尺寸。通过算例进行验证,结果显示所提方法在实现模型轻量化的同时有效提升了异纤检测效果和计算效率。

摘要：This paper extends a prediction model for multi-directional random wave transformation based on an energy balance equation by Mase with the consideration of wave shoaling, refraction, diffraction, reflection and breaking. This numerical model is improved by 1) introducing Wen's frequency spectrum and Mitsuyasu's directional function, which are more suitable to the coastal area of China; 2) considering energy dissipation caused by bottom friction, which ensures more accurate results for large-scale and shallow water areas; 3) taking into account a non-linear dispersion relation. Predictions using the extended wave model are carried out to study the feasibility of constructing the Ai Hua yacht port in Qingdao, China, with a comparison between two port layouts in design. Wave fields inside the port for different incident wave directions, water levels and return periods are simulated, and then two kinds of parameters are calculated to evaluate the wave conditions for the two layouts. Analyses show that Layout I is better than Layout II. Calculation results also show that the harbor will be calm for different wave directions under the design water level. On the contrary, the wave conditions do not wholly meet the requirements of a yacht port for ship berthing under the extreme water level. For safety consideration, the elevation of the breakwater might need to be properly increased to prevent wave overtopping under such water level. The extended numerical simulation model may provide an effective approach to computing wave heights in a harbor.

摘要：弹性车轮是城市轨道交通低地板有轨电车的重要组成部分，为了提高弹性车轮服役疲劳寿命，该文基于撕裂能理论，应用ABAQUS、FE-safe和Isight软件，对弹性车轮橡胶元件进行有限元建模、优化设计和疲劳寿命研究.首先，基于裂纹能量理论，研究了橡胶材料的疲劳特性，建立弹性车轮橡胶元件有限元模型并进行数值模拟计算，结果表明弹性车轮的刚度和疲劳寿命均未达到设计要求.其次，基于正交数值试验和Sobol模型，提出了一种改进的灵敏度分析方法，以最小应变为优化目标，选用改进灵敏度分析方法确定的结构参数为设计变量，建立二阶响应面模型，采用自适应多岛遗传算法对刚度约束条件下的弹性车轮橡胶元件进行单目标多因素优化设计，并对优化弹性车轮进行有限元数值模拟分析，结果表明优化弹性车轮结构的疲劳寿命比原弹性车轮结构提高了30%,优化弹性车轮的刚度和疲劳寿命均满足设计要求.最后，对优化弹性车轮分别进行径向加载试验和疲劳试验，结果表明有限元计算刚度曲线与试验刚度曲线吻合，且经历设计疲劳周次载荷循环的优化弹性车轮，其结构保持完整，验证了有限元模型和疲劳寿命数值模拟的有效性.

摘要：A new method to obtain supercontinuum(SC) source for multiplex coherent anti-stokes Raman scattering (CARS) microscopy is proposed. The nonlinear propagation in photonic-crystal fibers (PCF) of femtosecond pulse laser with central wavelength at 800.9 nm is studied with scalar wave theory. Based on the incident laser power and dispersion of PCF, super broadband source for multiplex CARS microscopy is designed.

摘要：新能源集群设备能源损失，使得集中控制效果差，导致整体能源利用效率下降，为有效控制新能源集群设备，设计基于微服务架构的新能源集控中心一体化平台。将单个应用服务拆分成多个微服务，采用不同服务器实现控制功能，结合分布式存储架构，设计平台硬件结构。针对综合能源系统内部的新能源设备集群进行稳态建模，采用稳态通用参数对新能源的波动能量进行描述与约束处理。在集控功能方面，分析燃气机轮和光伏机组的运行过程，结合稳态通用参数，对新能源集群设备稳态建模。以最大化设备运行效率、最小化能源损失和优化设备运行时间，构建协调控制函数，使用梯度下降法控制新能源设备能源损失。结果表明，设计方法的新能源集群设备运行功率波动值较低，具备较好的控制效果。

摘要：液晶光学相控阵被广泛应用于激光雷达、激光通信以及激光武器,进行激光光束的扫描控制。为了实现液晶相控阵的最优设计和激光光束高精度控制,本文重点研究了工作波长、像素数、像素尺寸及有效灰度数对光束指向精度的影响规律。首先,根据液晶相位调制原理,仿真分析了周期光栅法和变周期光栅法的有效扫描角度和衍射效率;然后,基于驱动电压灰度等分相位调制量,仿真分析了指向误差随工作波长、像素数、像素尺寸以及有效灰度数的变化规律,推导出多变量普适公式;接着,仿真分析了驱动电压灰度非等分相位调制量时的指向精度,并和等分相位调制量的结果进行对比分析;最后,实验验证了有效灰度数、像素数和指向误差的关系,初步证实了经验公式的有效性。本文的研究结果可为液晶相控阵的设计提供理论依据。

摘要：目的研究我国民俗文化创意产品创新设计的发展,进而找寻国民经济增长的有效途径。方法通过对国内外文化创意产业中民俗文化创意产品市场发展现状的调研分析,结合天津的现状及其存在的问题,论证如何充分利用民俗艺术进行文化创意产品设计风格的创新表现方法。结果深入挖掘传统民俗文化艺术的优势资源,并充分利用现代的设计理念与科学技术是进行民俗文化创意产品创新设计表现的捷径。结论随着全球经济的快速发展和文化的不断革新,民俗文化创意产品在创新设计中,不但要表现出民俗艺术形式美、个性美的民俗文化特点,而且更需要考虑到现代文创产品自身必备的特质和先进的科学技术制作手段,进而为当今我国城市的经济可持续发展开辟一条新路。

摘要：A 1200-V thin-silicon-layer p-channel silicon-on-insulator(SOI)lateral double-diffused metal-oxide-semiconductor(LDMOS)transistor is *** device named INI SOI p-LDMOS is characterized by a series of equidistant high concentration n+islands inserted at the interface of a top silicon layer and a buried oxide ***−mode holes,caused by the electric potential dispersion between the device surface and the substrate,are located in the spacing between two neighboring n+islands,and greatly enhance the electric field of the buried oxide layer and therefore,effectively increase the device breakdown *** on a 2−µm−thick buried oxide layer and a 1.5-µm−thick top silicon layer,a breakdown voltage of 1224 V is obtained,resulting in the high electric field(608 V/µm)of the buried oxide layer.

摘要：　选用导热系数很小的无机填料和增韧效果好的石棉纤维对环氧树脂进行填充改性;采用硅烷偶联剂对无机填料和石棉纤维进行表面处理,提高无机填料与聚合物基体的界面相互作用;用自行设计的方法测试材料的隔热性能.结果表明:导热系数小的无机填料明显地改善了环氧树脂复合材料的隔热性能,石棉纤维极大地提高了环氧树脂的冲击韧性,环氧树脂复合材料做成的电缆桥架已投入试运行,并且运转效果良好.