基于路面识别的HEV制动系统控制算法研究

为实现ISG混合动力汽车最大限度地回收再生制动能量,并保证其制动安全性,提出了一种协调再生制动系统和液压制动系统制动力矩动态分配的控制算法。该控制算法以路面识别为基础,以在制动过程中车轮滑移率为路面的最佳滑移率为控制目标,实时计算并动态调整前后轮液压制动力矩和再生制动力矩,保证在制动过程中车轮获得最大的附着系数。仿真结果验证了所制定的控制算法的稳定性和有效性。

Abstract：

In order to recycle braking energy as much as possible and ensure the safety in braking for ISG Hybrid Electric Vehicles,a novel coordinated control algorithm was proposed for dynamical distribution between regenerative braking torque and hydraulic braking torque.To assure that the adhesion coefficient of wheels is maximal during braking,the control algorithm based on the Road identification synchronously calculates and dynamically adjusts front wheel hydraulic braking torque,rear wheel hydraulic braking torque,regenerative braking torque and makes Slip Ratio of wheels equal to Optimal Slip Ratio all along.The simulation results show that the proposed control algorithm is steady and effective.     

Design and realization of a novel multitask TT&C operation pattern

With the sharp increase of China＇s in-orbit spacecraft and the constraint TT＆C resources, a mathematical model for optimal TT＆C resource allocation is proposed, and the TT＆C facility remote monitoring function is designed to achieve the multitask operation pattern under the unified management of the network management center. With this pattern, the TT＆C network management and the spacecraft management are separated, which is quite different from the previous pattern. Further, a novel spacecraft TT＆C technique based on spacecraft control language is developed, and the telecommanding pattern is designed to address the spacecraft operation problems. The engineering application shows that this pattern fundamentally improves the TT＆C network capability, increases the resource efficiency, and satisfies the efficient, accurate, and flexible operation of spacecraft.     

The influence of Disposition Effect on Stock Return in China

This paper introduces the disposition effect into asset pricing process, and sets dynamic equilibrium model on which we can discuss the pattern of risk assets＇ returns. On base of theory results, we use data of China stock market to analyze the influence of disposition effect on stock return. The empirical study result confirms the disposition effect＇s existence in China stock market and it does affect the stock return.     

Virtual reality mobility model for wireless ad hoc networks

For wireless ad hoc networks simulation, node＇s mobility pattern and traffic pattern are two key elements. A new simulation model is presented based on the virtual reality collision detection algorithm in obstacle environment, and the model uses the path planning method to avoid obstacles and to compute the node＇s moving path. Obstacles also affect node＇s signal propagation. Considering these factors, this study implements the mobility model for wireless ad hoc networks. Simulation results show that the model has a significant impact on the performance of protocols.     

Design and simulation of fault diagnosis based on NUIO/LMI for satellite attitude control systems

This paper presents a scheme of fault diagnosis for flexible satellites during orbit maneuver. The main contribution of the paper is related to the design of the nonlinear input observer which can avoid false alarm arising from the disturbance from orbit control force. The effects of orbit control force on the fault diagnosis system for satellite attitude control systems, including the disturbing torque caused by the misalignments and the model uncertainty caused by the fuel consumed, are discussed, where standard Luenberger observer cannot work well. Then the nonlinear unknown input observer is proposed to decouple faults from disturbance. Besides, a linear matrix inequality approach is adopted to reduce the effect of nonlinear part and model uncertainties on the observer. The numerical and semi-physical simulation demonstrates the effectiveness of the proposed observer for the fault diagnosis system of the satellite during orbit maneuver.     

一种语义扩展的DEVS模型表示方法

离散事件系统规范（DEVS）是建立在一般系统理论的基础上的有效的模块化系统建模规范。针对当前基于DEVS的仿真模型表示方法不能描述模型上下文,不能有效支持模型语义组合、重用的问题,提出了语义扩展的DEVS模型表示方法（SEM-DEVS）。SEM-DEVS在原有的DEVS模型规范基础上,增加了模型的实验框架和语义扩展接口,增加了对模型行为表示能力的要求。在SEM-DEVS形式化定义的基础上给出了实验框架以及语义扩展接口的逻辑关系及匹配方法。以逻辑公式方式表示实验框架和语义扩展接口,给出SEM-DEVS的一种实现方法。

Abstract：

Based on general theory, DEVS is an effective and module modeling specification. For the problem of lacking capability of current model representation approaches to describe context and support semantics reuse and composition of simulation model, a Semantic Extended DEVS （SEM-DEVS） model representation approach was proposed. On the base of DEVS, experiment frame and semantic extended port of model were extended to SEM-DEVS. Stricter request to describe the behavior of model was proposed in SEM-DEVS. Logic relationship and match method of experiment frame and semantic extended port of model was brought forward base on formal definition of SEM-DEVS. An implement of SEM-DEVS was proposed, in which experiment frame and semantic extended port were both represented by logic formulas.     

Learning algorithm and application of quantum BP neural networks based on universal quantum gates

A quantum BP neural networks model with learning algorithm is proposed. First, based on the universality of single qubit rotation gate and two-qubit controlled-NOT gate, a quantum neuron model is constructed, which is composed of input, phase rotation, aggregation, reversal rotation and output. In this model, the input is described by qubits, and the output is given by the probability of the state in which （1） is observed. The phase rotation and the reversal rotation are performed by the universal quantum gates. Secondly, the quantum BP neural networks model is constructed, in which the output layer and the hide layer are quantum neurons. With the application of the gradient descent algorithm, a learning algorithm of the model is proposed, and the continuity of the model is proved. It is shown that this model and algorithm are superior to the conventional BP networks in three aspects： convergence speed, convergence rate and robustness, by two application examples of pattern recognition and function approximation.     

基于Dymola的液压系统热力学模块化建模与仿真

以模块化建模方法为指导,提出了液压系统的热力学模块化建模方法。将液压元件工作机理分为容积型和阻尼型,建立容积型模块和阻尼型模块模型,由容积型模块和阻尼型模块单独或组合建立液压元件的模块化模型。采用Dymola对所建立的各元件模型进行仿真实现,建立了温度仿真模块库-ThermalHydraulic,可以实现面向液压原理图的可视化温度仿真。对模块库进行测试,验证了建模和仿真实现的可行性。

Abstract：

According to the modular modeling method,a thermal-hydraulic modular modeling method of hydraulic system was presented. Basic operating principles of all hydraulic components were divided into two types：volume and resistance. Volume model and resistance model were developed to represent the volume and resistance characteristic of hydraulic component. Component＇s modular model was established by signal or both of volume model and resistance model. Then,the hydraulic system temperature simulation modular library-Thermal Hydraulic was established by Dymola software,and the library could establish system model conveniently by visual modeling style based on hydraulic principle figure. At the last,the system test was made to evaluate the feasibility of modeling and simulation.     

Price Masking Strategy of Cross-Border E-Commerce Platform Financing

E-commerce platform financing is a new service pattern of supply chain finance. However,this pattern may bring some new issues when considering the problem of cash flow shortage and financing difficulties of small and medium-sized enterprises. When enterprises use this service, they worry about the leakage of preferential wholesale price when applying the full loan amount and providing the true transaction information. Based on the model consisting of a supplier, a retailer and a crossborder e-c...     

多阶段分散化投资组合效率估计

The existing multi-period portfolio diversification performance evaluation models are mainly divided into two categories. The first category is to build a performance evaluation model based on the return rate of portfolio at each period. The other category is to evaluate portfolio performance by using efficient frontier. However, the former ignores the dynamic relationship among the time periods, while the latter has limitations when there exists friction in financial market. To address this problem, the actual investment of the input-output process was clarified and defined, and the definition of multi-period portfolio efficiency were given based on the distance between portfolio under evaluation and its projection point on the efficient frontier. Under the multi-period mean-variance theoretical framework, the middle connection condition in the multi-period portfolio evaluation problem was derived by using the wealth dynamic process, so as to build a two-period portfolio efficiency estimation model under different orientation. Since the above-mentioned middle connection condition is random, it not workable in actual evaluation. Therefore, in this paper, the first moment and second moment of the above random conditions were used to replace the original one, and another kind of two-period portfolio efficiency estimation model was built. The numerical analyses show that this proposed model is effective.     

液压型风力发电机组并网冲击仿真研究

以液压型风力发电机组励磁同步发电机系统和并网控制系统为研究对象,针对励磁同步发电机的准同期并网条件,建立了同步发电机和励磁系统数学模型。理论分析了同步发电机并网冲击电流和冲击转矩。通过MATLAB/Simulink建立同步发电机、励磁系统和准同期锁相模块仿真模型,采用AMESim软件建立液压调速系统模型,采用联合仿真的方法,对液压型风力发电机组准同期并网过程进行研究,分析了系统并网冲击特性。在实验室搭建30kVA实验台,实验验证了仿真模型和仿真结果的正确性。研究表明定量泵-变量马达液压调速系统能将同步发电机转速稳定控制在准同期并网条件范围内,同时能有效控制系统并网冲击,使风力发电机组平稳并入电网。     

液力变矩器泵轮叶片优化设计研究

提出一种液力变矩器叶栅系统的优化设计方法,通过含有参数化设计与流场数值模拟环节的正交试验设计样本构建目标的响应曲面(RSM)近似模型,再由序列二次规划法(SQP)反复迭代并更新模型逼近最优解。结果表明该方法在工程设计上是有效的,并且证实了加大泵轮叶片内环出口角的扭曲角度可以有效地提高变矩器的变矩性能,但起动变矩比增大的同时最高传动效率会有所下降。     

合作机器人的控制策略及仿真

合作机器人（cobot）是与人在同一作业空间内直接进行物理合作的机器人。为了实现cobot直接与人合作作业,根据cobot的特点,建立了不完全约束关节机构的模型和cobot的控制模型,提出了cobot的控制策略。建立了控制策略的仿真模型,对cobot跟踪给定直线和圆弧进行了仿真研究。研究结果表明：这种控制策略是可行的,它能在人机合作的条件下使cobot跟踪期望轨迹。当操作力为0时,cobot静止不动,因此不会因为机器人失控而伤害操作者,满足了人机合作的要求。这种控制策略可以应用在外科手术、物料搬运和零件装配的合作机器人中。     

基于控制组态软件的火电发电机组仿真研究

以350MW火力发电机组为仿真对象,开发了一台基于PineCAD工程控制组态软件的电厂火电系统仿真机。介绍其中的发电机组的仿真研究,建立了发电机变压器系统数学模型、同期并网系统数学模型和电网控制系统数学模型,这三部分再与电气系统控制逻辑、电厂操作的人机界面相链接,构成了发电机组电气仿真系统。通过将仿真数据同机组实际运行数据进行比较分析,所建立的发电机组模型能够满足仿真精度的要求,仿真机交付电厂使用,对运行人员进行基本的培训,取得效果满意。     

旋转弹舵机控制滞后及延迟补偿时间分析

针对十字鸭舵布局的双通道旋转弹控制滞后问题,从舵机控制力角度建立控制模型,推导了控制力滞后角的计算公式;从系统组成方面对指令的形成与传输过程进行了分析,得出滞后形成的两方面原因:地磁陀螺和弹载计算机引起的舵机输入指令信号延迟和舵机性能引起的舵机指令响应信号延迟;利用滞后角计算公式和正弦波扫频法,得到低转速下舵机输入指令信号和指令响应信号的延迟补偿时间为常数;提出根据延迟补偿时间常数和转速进行滞后补偿的方法,并进行了实验验证。实验结果表明,此方法具有良好的补偿效果。     

基于刚柔混合建模的柴油机曲轴系动态仿真

在分析PA6V12柴油机曲轴系运动及受力的基础上,利用Pro/E对曲轴系进行了整体造型,同时利用PATRAN对曲轴进行了有限元建模,通过ADAMS/View构建了曲轴系的刚柔多体动态仿真模型.模型主要考虑了柴油机在额定工况下的边界条件.结果分析表明,该模型能够准确的反映曲轴系的运动和受力情况,其结果也为曲轴动态有限元的疲劳寿命计算提供了依据.     

船舶轴带发电机系统的仿真设计与建模

介绍了WMS2000型轮机仿真器中轴带发电机的工作原理、仿真系统设计及数学建模方法，并给出了部分具体数学模型。仿真轴带发电机采用西门子轴带发电机系统作为仿真母型。经简化设计，仿真轴带发电机系统包括休控室的操作屏、机舱的整流／逆变屏和电站监控计算机中的模拟检测系统。建立了能量系统模型、电力回路系统模型和控制系统模型。能量系统模型遵循能量守衡定律，电力回路模型估算了电流、电压及频率等参数，控制系统模型依据特性曲线得到。所建立的数学模型可仿真轴带发电机系统的正常及非正常工况，达到了较高的稳成和动态仿真精度。     

大型变速风力发电机组的自适应模糊控制

控制技术是风力发电机组安全高效运行的关键。风力发电机组是复杂多变量非线性系统,具有不确定性和多干扰等特点。本文提出使用模糊逻辑推理系统得到低风速时的发电机参考转速,该方法无需测量风速,避免了风速测量的不精确性。根据机组的运动方程,采用最近邻聚类学习算法建立发电机电磁转矩自适应最优模糊控制,低风速时获得最大风能利用系数。算法综合考虑风力发电机组的机械特性和电气特性,系统辨识作为控制算法的一部分自动执行。高风速时,变论域自适应模糊控制器控制桨距角,机组能准确地保持在额定功率发电。仿真结果表明了本文提出方法的有效性。     

永磁同步电机位置跟踪控制器及Backstepping方法建模

针对永磁同步电机(PMSM)绕组相电流和转速强耦合特性，基于backstepping方法设计了高性能的位置跟踪控制器，并建立了采用该控制器的PMSM伺服系统仿真模型。仿真结果表明，用backstepping方法设计的PMSM控制系统可以获得很好的跟踪效果，并且其滤波跟踪误差迅速以指数特性收敛到零，具有很好的位置伺服控制特性。     

永磁同步电动机自适应反步控制的建模与仿真

设计了一种基于自适应反步控制的永磁同步电动机非残性速度控制器，采用二阶滤波环节平滑速度指令．在设计非线性速度控制器的同时，进行不确定参数及负载力矩的在线自适应估计。建立了采用该控制器的永磁同步电动机速度伺服系统仿真模型．仿真结果表明，所设计的非线性控制器保证了系统的全局一致稳定性，永磁同步电动机伺服系统获得了很好的跟踪效果，并且对参数不确定性及负载力矩扰动具有很好的鲁棒性。