Difference control of parallel streams temperatures

This paper is concerned with controller design for a multi-stream, multi-burner furnace commonly seen in petroleum refineries. The process of the oil heating in the furnace is nonlinear, multivariable, time varying, has serious coupling between streams and burners, has frequent dynamic changes and a large time delay. In order to maintain the furnace running in a safe, stable and high efficiency state it is necessary to control the outlet temperatures of the multiple streams to be the same. Traditional control methods have trouble in maintaining these temperatures, and some advanced control methods including predictive control, adaptive control and robust control are usually too complex for convenient use.In this paper, a novel multivariable controller design based on a difference control technique (DCT) is explained and demonstrated. The application of the DCT to a real-life petroleum refinery furnace gave good results. The DCT design method has the following advantages: it does not need complicated design procedures, the controller structure is simple, it is easy to apply, and it eliminates the problem of coupling among multiple loops.     

并联新能源汽车最优效率实时控制

为了提高并联混合动力汽车驱动系统的实时效率,降低燃油消耗,本文提出一种基于效率最优的协调控制策略.根据不同驱动模式下电池的充放电状态,建立了充放电状态下驱动系统的等效燃油消耗模型,在分析电池效率和发动机效率的基础上,得到驱动系统效率的统一表达式,进而通过建立不同功率需求不同荷电状态下系统最优效率的功率分配系数图谱,设计了系统效率最优的协调控制策略,协调控制策略根据优化的功率分配系数在发动机和电机间进行力矩分配,协调控制策略可以离线计算并实时执行.两种工况循环下的仿真结果表明效率最优控制策略能有效地提高混合动力系统实时效率和燃油经济性.     

Generalized predictive control for non-uniformly sampled systems

In this paper, we study digital control systems with non-uniform updating and sampling patterns, which include multirate sampled-data systems as special cases. We derive lifted models in the state-space domain. The main obstacle for generalized predictive control (GPC) design using the lifted models is the so-called causality constraint. Taking into account this design constraint, we propose a new GPC algorithm, which results in optimal causal control laws for the non-uniformly sampled systems. The solution applies immediately to multirate sampled-data systems where rates are integer multiples of some base period.     

一种H.264/AVC码率控制的改进算法

为了在网络带宽受限的情况下获得更好的重建图像质量,码率控制成为视频编码不可缺少的重要组成部分。针对H.264/AVC码率控制算法的不足,提出了改进方法。首先通过PSNR-QP线性关系确定I帧的QP;其次,在采用二次R-Q模型来确定P帧的QP时,采用时间线性预测模型和时空加权预测模型相结合的方法取代H.264的时间线性预测模型来预测P帧基本单元的MAD值,并根据前一单元的预测误差对MAD值进行修正。实验结果表明,与JM10.2参考软件的码率控制算法相比,该算法的码率控制精度更高,输出视频序列的平均PSNR更高、波动更小。     

基于粒子群优化算法的广义逆控制分配方法

为了获取具有最高分配效率的加权矩阵,将粒子群算法应用于广义逆控制分配法设计,通过计算不同广义逆阵所能有效分配的转矩可达集体积,来选择具有最高分配效率的加权矩阵。以某飞机的控制效率矩阵进行基于广义逆分配法分配器设计,通过粒子群算法对加权矩阵进行寻优,有效地选取了具有最优分配效率的广义逆阵,显著地提高了分配器的分配效率。     

基于改进双向测距到达时间差定位算法的超宽带定位系统

针对传统无线定位技术在室内定位精度不高的问题,设计实现了一种基于超宽带（UWB）技术的室内定位系统。首先,提出了定位服务器与移动端APP实时交互的系统结构,解决室内移动人员自主定位与导航的问题。其次,在双向测距（TWR）算法中增加一条无线电信息以减小时钟偏移引起的测距误差,从而提高算法性能。最后,将通过到达时间差（TDOA）定位算法得到的双曲面方程组进行线性化处理后结合Jacobi迭代法完成求解,避免了使用标准TDOA定位算法难以直接解算的情况。经测试,该系统在楼道房间等场景中能稳定工作且定位误差控制在30 cm以内,相比基于WiFi、蓝牙等技术的定位系统在定位精度上提高了10倍左右,能够满足在复杂室内环境中的精确移动定位需求。     

Minimizing total earliness and tardiness through unrelated parallel machine scheduling using distributed release time control

Using unrelated parallel machine scheduling to minimize the total earliness and tardiness of jobs with distinct due dates is a nondeterministic polynomial-hard problem. Delayed customer orders may result in penalties and reduce customer satisfaction. On the other hand, early completion creates inventory storage costs, which increase the total cost. Although parallel machines can increase productivity, machine assignments also increase the complexity of production. Therefore, the challenge in parallel machine scheduling is to dynamically adjust the machine assignment to complete the job within the shortest possible time. In this paper, we address an unrelated parallel machine scheduling problem for jobs with distinct due dates and dedicated machines. The objective is to dynamically allocate jobs to unrelated parallel machines in order to minimize the total earliness and tardiness time. We formulate the problem as a mixed integer linear programming (MILP) model and develop a modified genetic algorithm (GA) with a distributed release time control (GARTC) mechanism to obtain the near-optimal solution. A preliminary computational study indicates that the developed GARTC not only provides good quality solutions within a reasonable amount of time, but also outperforms the MILP model, a classic GA and heuristic approaches described in the literature.     

单轴联结式并联混合动力汽车分层切换控制设计

为提高整车燃油经济性,降低尾气排放,本文针对单轴联结式并联混合动力汽车(parallel hybrid electric vehicle,PHEV)提出了一种分层切换控制方法.首先,在分析发动机稳态效率和电池充放电内阻变化规律基础上,采用分层切换思想,制定了PHEV各运行模式间切换规则.然后,研究了不同目标运行模式下的能量分配策略,针对单一驱动模式和3种制动模式,设计了基于规则的转矩分配策略;针对混合模式,分别设计了行车充电/混合驱动模式下的Lyapunov优化功率分配策略以及驻车充电模式下的Willans line模型极值法功率分配策略.最后,仿真结果表明,所提出方法可确保发动机和电池工作在高效区.在UDDS+HWFET工况下,与电辅助策略相比,百公里油耗降低了40.82%,CH,CO和NOx的排放量分别减少了2.86%,4.41%和8.02%;与基于庞特里亚金最小值原理(Pontryagin’s minimum principle,PMP)的全局优化策略相比,百公里油耗降低了9.37%.     

Generalized discrete-time PI control of output PDFs using square root B-spline expansion

A new control approach is proposed for the probability density function (PDF) control of non-Gaussian stochastic systems using PI controllers. Using the square root output PDF model and the weight dynamics, the PDF tracking is transformed to a constrained dynamical tracking control problem for weight dynamics, where LMI techniques are used to design a generalized PI controller such that stability, state constraints and tracking performances can be guaranteed simultaneously.     

混合值差度量在MDS算法中的应用

多维尺度分析（MDS）通常以欧氏空间中点的距离来度量对象间的差异性（相似性）。当对象有像性别、颜色等名义属性时,通常的做法是将它们数量化,然后再对其运用欧氏距离,显然,这种处理方法存在不合理性。将一种混合值差度量（HVDM）引入含名义属性的对象间距离的计算,以改善名义属性下MDS的计算合理性。在UCI Abalone数据集上进行的实验,结果表明该方法比传统的数量化方法在重构能力、重构精确度方面都有更好的表现。     

基于单指令多数据技术的H.264编码优化

简要介绍了单指令多数据（Single-Istruction Multiple-Data，SIMD）指令系统，并用该技术对H.264中的整数离散余弦变换（Discrete Cosine Transform，DCT）、量化、插值和运动估计等模块进行了优化，实验结果表明优化后程序的编码速率可达到30fps左右，比未优化时速度提高了6～8倍。     

基于遗传算法的六自由度并联平台的控制

由于单通道电液位置伺服系统是一种非线性时变系统,而且有阻尼比小、参数变化大、非线性程度高的特点,传统的PID控制已经很难满足六自由度并联平台的控制精度的要求。针对六自由度并联平台单通道的数学模型,采用遗传算法对其PID控制器的参数进行优化控制,以满足系统的控制精度的要求。仿真结果表明该控制系统的性能指标有了很大改善,证明了该遗传算法的可行性和有效性,克服了传统PID整定参数费时的缺点,对解决实际控制问题提供了有效的方法,并且具有良好的抗干扰能力,其适应性(鲁棒性)也有了很大的提高。     

固定翼无人机自动着陆的一体化制导控制

本文基于制导控制一体化方法的思想,将滑模变结构控制和自抗扰控制技术结合于动态面控制结构中,提出一种固定翼无人机自动着陆方法.在建立六自由度无人机模型、无人机和目标点间的相对视线角度模型的基础上,在动态面控制框架下加入滑模变结构控制来设计制导控制一体化方法.在此过程中加入自抗扰控制技术,提高了系统对未建模部分、参数的不确定性和外界干扰的鲁棒性,并抑制了滑模变结构控制的抖振.该方法使得无人机在平稳地飞向目标点的同时能够满足着陆视线角度的约束.文中详细论述设计思想和设计方法,最后通过仿真验证说明本文方法的有效性.     

Hybrid intelligent control of combustion process for ore-roasting furnace

Because of its synthetic and complex characteristics, the combustion process of the shaft ore-roasting furnace is very difficult to control stably. A hybrid intelligent control approach is developed which consists of two systems： one is a cascade fuzzy control system with a temperature soft-sensor, and the other is a ratio control system for air flow with a compensation model for heating gas flow and air-fuel ratio. This approach combined intelligent control, soft-sensing and fault diagnosis with conventional control. It can adjust both the heating gas flow and the air-fuel ratio in real time. By this way, the difficulty of online measurement of the furnace temperature is solved, the fault ratios during combustion process is decreased, the steady control of the furnace temperature is achieved, and the gas consumption is reduced. The successful application in shaft furnaces of a mineral processing plant in China indicates its effectiveness.     

Multivariable temperature measurement and control system of large-scaled vertical quench furnace based on temperature field

A temperature control system of 31m vertical forced air-circulation quench furnace is proposed,which is a kind of equipment critical for thermal treamlent of aluminum alloy components that are widely used in aerospace industry. For the effective operation of the furnace, it is essential to analyze the radial temperature distribution of the furnace. A set of thermodynamic balance equations modeling is established firstly. By ufilizmg the numerical analysis result to modify the temperature measurements, the control accuracy and precision of the temperature are truly guaranteed. Furthermore, the multivariable decouplmg self-learning PID control algorithm based on the characteristics of strong coupling between the multi-zones in the large-scaled furnace is implemented to ensure the true homogeneity of the axial temperature distribution. Finally, the redundant structure composed of industrial control computers and touch panels leads to great improvement of system reliability.     

DDE技术及其在先进控制技术中的应用

结合OPC和DDE技术,建立了对现场实时数据的采集以及历史数据的接收方法.通过OPC和DDE采集上来的数据,可用于预测控制算法的仿真和优化.并根据需要建立DDE服务器,将实时数据与历史数据传送给上位机的其他应用程序,这样便可以利用PC机的丰富资源对数据进行处理.     

A synthesizing control model of networked control systems to guarantee QoP and QoS

The whole performance of the networked control system （NCSs） depends on two interaction factors, namely the quality of control performance （QoP） and quality of network service （QoS）. So, to optimize the whole perfor-mance of NCSs, the problem of guaranteeing QoP and QoS plays an important role in the design of NCSs. However, up to now, little work has been done in this field. In this paper, a synthesizing control model of NCSs to guarantee QoP and QoS is proposed, and a feasible condition of optimizing whole performance of NCSs is also suggested. Finally, the simulation results show that the proposed model is effective.     

Augmented TP model transformation‐based parallel distributed compensation control design

The usual sampled hyper grid points of uniform sampling method are distributed equally in the TP model transformation, thus, the sampling results often omit the local extrema when the sampling step is not fine‐tuned. Then the resultant tensor which is used for controller design can not fully cover the state space, although the gain which is the feasible solution of the linear matrix inequalities. In this paper, we proposed a non‐uniform sampling method for tensor product model transformation, local extrema are considered in the sampling step, while the sampling step can vary dynamically for different function entries. In this paper, TP model transformation‐based parallel distributed compensation (PDC) controller is extended in three folds: (i) The existing TP model transformation‐based PDC controller with uniform sampling method is extended to TP model transformation‐based PDC tracking controller with the uniform sampling method and an extended signal. (ii) A new TP model transformation‐based PDC tracking controller is proposed based on a new sampling method, that is, the Hammersley sampling method. (iii) TP model transformation‐based PDC tracking controller is also proposed based on the non‐uniform sampling method. The proposed adaptive TP model transformation‐based PDC tracking controller is able to enhance the performance of the TP model transformation‐based PDC controller, and the adaptive TP model transformation‐based PDC controller obtains the best results due to the nearly exact sampling of the system.     

基于高斯差分特征网络的显著目标检测

中心-邻域对比度理论作为具有生理学依据的一种线索,在传统显著性检测模型中获得了广泛应用,然而该理论却很少显式地应用在基于深度卷积神经网络(CNN)的模型中.为了将经典的中心-邻域对比度理论引入深度卷积网络中,提出了一种基于高斯差分(DoG)特征网络的显著目标检测模型.首先通过在多个尺度的深度特征上构造高斯差分金字塔(D...     

改进Smith控制与RBF单神经元PID的换热器控制系统

为了高效控制工质出口温度,维持换热器稳定运行,针对Smith预估控制算法及径向基函数(RBF)神经网络辨识单神经元比例-积分-微分(PID)控制算法特点,提出了Smith控制算法和RBF神经网络辨识单神经元PID相结合的控制策略,对Smith控制算法在结构上进行了改进,以提高RBF神经网络辨识单神经元PID控制的抗干扰能力,减少Smith控制算法对模型的依赖程度.仿真分析表明:应用于换热器工质出口温度控制系统,改进算法控制性能显著优于其它控制方法,抗干扰能力得到了大幅提高.