红外测温在浆纱机上的应用

本文介绍了红外测温的技术。运用这项技术,可以测得用常规方法难以得到的浆纱机上主要部件(例如:烘筒、纱片、烘房及压浆辊等等)的动态表面温度。快速、及时地测得这些温度数据,有助于改进设计,使工艺流程控制恰到好处。它关系着上浆质量、汽耗、电耗以及生产效率。这项技术在生产上的应用是件很有经济效益的事。     

A Study on the Tensile Properties of the MWK Structures for Composite Reinforcement

IntroductionOne of the current trends for textile structuralcomposites is to expand their applications from secondarynon load bearing structures to primary load bearingstructures. This requires a significant improvement of thedamage tolerance and reliability. For the thin mediumthickness structures, an attractive family of textilestructures, Multiaxial WarpKnitted(MWK) structures, hasthepotential to meet the demand for structural composites.All layers o…     

一种自适应神经网络的信号盲分离及实验

介绍一种提高收敛速度的基于自适应在线学习的盲信号分离算法,以Kullback-Leibler散度作为代价函数,运用随机梯度下降导出算法,在估计分离矩阵的同时更新学习率。实验证明,该算法对于混合图像信号能够有效地分离,利用自适应学习参数提高了盲信号分离的收敛速度及算法性能,结果证实了算法的有效性。     

工缝机的差动送料机构与缝纫性能

在“工缝机上下差动送料系统的分析研究”一文中,我们建立了上下送料牙运动轨迹方程,并用计算机进行模拟计算,确定出各机构之间的相位角以及某些可调参数值。本文在此基础上探讨了各机构之间的相位角对缝纫送料性能的影响,得出相位角的最佳值及允许变动的范围。这对机器的设计和安装有重要意义。     

基于支持向量机的故障过程趋势预测研究

提出了运用SVM机器学习方法进行故障过程趋势预测的方法，并设计了一个实用的SVM回归算法对“Tennessee Eastman”工厂的实际数据进行仿真研究，结果表明，用SVM方法进行故障过程趋势预测，具有较强的抗噪能力，在样本量有限情况下，采用ε－不敏感损失函数得到的回归结果具有较高的实用价值，通过大量实验，给出了ε取值不同对估计结果的影响的一个具体实验结果，分析了ε取值对支持向量数目的控制作用。     

一种用于多径信道的调制识别算法仿真研究

无线信道的多径衰落造成通信信号的码间干扰,为通信信号的调制识别增加了难度。针对多径环境下的调制识别问题,提出了一种基于改进的外积分解信道盲辨识算法的调制识别新算法。算法首先对信道进行基于改进算法的信道盲辨识和盲均衡,然后对均衡结果提取高阶累积量特征完成调制识别。与已有算法相比,改进的外积分解算法提高了在信道阶数过估计条件下对噪声的鲁棒性,所提出的调制识别算法扩大了识别种类,提高了识别性能。仿真结果证明了算法的有效性。     

基于LMDI-CS-LSSVM的区域中长期电力需求预测

中长期用电需求预测对地区电网规划与运行具有重要意义,准确地对其进行预测有助于配电网利用效率的提高。中长期用电需求与地区宏观经济形势息息相关,本文选用LMDI分解模型对用电增长量进行了分解,根据影响因素分解为生产效应、结构效应及强度效应,然后选用布谷鸟搜索优化的最小二乘支持向量机对各效应数据进行拟合及预测,再加总得到预测用电需求量。最后,本文以冀北地区为例对模型进行测算,通过与不同预测方法比较证明了基于LMDI电量分解的CS-LSSVM模型在中长期电力需求预测方面有较高的准确度。     

Blind reconstruction of convolutional code based on segmented Walsh-Hadamard transform

Walsh-Hadamard transform （WriT） can solve linear error equations on Field F2, and the method can be used to recover the parameters of convolutional code. However, solving the equations with many unknowns needs enormous computer memory which limits the application of WriT. In order to solve this problem, a method based on segmented WriT is proposed in this paper. The coefficient vector of high dimension is reshaped and two vectors of lower dimension are obtained. Then the WriT is operated and the requirement for computer memory is much reduced. The code rate and the constraint length of convolutional code are detected from the Walsh spectrum. And the check vector is recovered from the peak position. The validity of the method is verified by the simulation result, and the performance is proved to be optimal.     

Adaptive subsequence adjustment with evolutionary asymmetric path-relinking for TDRSS scheduling

Due to the limited transmission resources for data relay in the tracking and data relay satellite system （TDRSS）, there are many job requirements in busy days which will be discarded in the conventional job scheduling model. Therefore, the improvement of scheduling efficiency in the TDRSS can not only help to increase the resource utilities, but also to reduce the scheduling failure ratio. A model of nonhomogeneous parallel machines scheduling problems with time window （NPM-TW） is firstly built up for the TDRSS, considering the distinct features of the variable preparation time and the nonhomogeneous transmission rates for different types of antennas on each tracking and data relay satellite （TDRS）. Then, an adaptive subsequence adjustment （ASA） framework with evolutionary asymmetric path-relinking （EvAPR） is proposed to solve this problem, in which an asymmetric progressive crossover operation is involved to overcome the local optima by the conventional job inserting methods. The numerical results show that, compared with the classical greedy randomized adaptive search procedure （GRASP） algorithm, the scheduling failure ratio of jobs can be reduced over 11% on average by the proposed ASA with EvAPR.     

基于虚拟暗室技术的电动车电磁辐射现场测试系统设计

针对电动汽车电磁辐射测试问题,提出一种基于虚拟暗室技术的电动汽车电磁辐射干扰现场测试系统设计方案。首先,在分析电动汽车电磁辐射特征和虚拟暗室技术要求的基础上,采用多点同步方法检测节点阵列,构建适应电动汽车全工状态的电磁辐射虚拟暗室现场测试系统;然后,对测试系统中的辐射信号和噪声信号的盲源分离数学模型进行研究,建立基于迭代算法的多通道同步信号分离算法;最后,对系统进行仿真测试。测试结果表明,该系统能够对小信噪比、多通道主噪信号进行有效分离,可用于纯电动汽车电磁辐射干扰的检测与特性分析。