Improved Hungarian algorithm for assignment problems of serial-parallel systems

In order to overcome the shortcoming of the classical Hungarian algorithm that it can only solve the problems where the total cost is the sum of that of each job, an improved Hungarian algorithm is proposed and used to solve the assignment problem of serial-parallel systems. First of all, by replacing parallel jobs with virtual jobs, the proposed algorithm converts the serial-parallel system into a pure serial system, where the classical Hungarian algorithm can be used to generate a temporal assignment plan via optimization. Afterwards, the assignment plan is validated by checking whether the virtual jobs can be realized by real jobs through local searching. If the assignment plan is not valid, the converted system will be adapted by adjusting the parameters of virtual jobs, and then be optimized again. Through iterative searching, the valid optimal assignment plan can eventually be obtained.To evaluate the proposed algorithm, the valid optimal assignment plan is applied to labor allocation of a manufacturing system which is a typical serial-parallel system.

MODELING AND PERFORMANCE ANALYSIS FOR THE SERIAL AND PARALLEL PRODUCTION SYSTEM BASED ON GSPN

Differed from the existed applications of generalized stochastic Petri net(GSPN) theory in machine-tool manufacturing system, reliability computation of FMS, testabilityparameters determination and fault analysis, a new idea of applying GSPN to model and performanceanalysis for the serial and parallel production system is proposed. And one typical discrete eventdynamic system (DEDS), turner-unit of palletizing system, is taken as a real case to research. Basedupon the established GSPN models, the working performances of serial and parallel layout arecompared. Furthermore, their differences of working mechanisms including feeding mechanism,coordinating mechanism and monitoring mechanism are discussed. Thus the theoretical basis which ishelpful to appraise layout plan and its reasonableness is provided. Meanwhile, the research resultsshow that parallel layout is more advantageous to greatly improve the operational speed ofproduction system than serial one.

ANALYSIS OF MULTI-TONE INTERFERENCE SUPPKESSION IN HF SERIAL DATA TRANSMISSION SYSTEM

The multi-tone interference suppression in HF serial data transmission systemsis analyzed.Analytic expression for the tap weights and minimum mean square errors of theadaptive equalizer in HF serial systems are obtained.The rate of convergence of equalizer indicatethat the equalizer in HF serial system can not only track the rapid variation of HF channel butalso suppress the multi-tone interferences perfectly.

ON PROPERITIES OF A SERIAL SERVICE SYSTEM OF TWO SERVICE COUNTERS WITH FINITE WAITING SPACE

In the paper,a serial service System involving two service counters with finite walting space is discussed based on Serial queueing system with two service mechanism. Moreover,thegeneral recurrence formulas of probalillty distribution Pi.j}of the system under statistical equibrium are derived and several corresponding quantitative indexes are given.

STUDY ON USING SERIAL PIPE TO IMPROVE THE DYNAMIC RESPONSE OF ELECTRO－HYDRAULIC SPEED CONTROL SYSTEM

The mathematical models of electro-hydraulic speed control system using series of pipesis presented. The principle of pipe effection on dynamics of the system is developed. Computersimulation and physical experiment are also carried out. The experimental results show that a rightchoosing of serial pipe for electro-hydraulic system enables the dynamic response of the system tobe improved effectively.

不完美维护下质量退化系统生产维护联合优化

针对设备劣化串联生产系统中质量退化问题,基于维纳过程对设备劣化建模,考虑设备不完美维护对残余劣化量和残余劣化率的综合影响,提出基于实时产品质量信息的设备不完美维护与换新策略,并与生产计划联合优化,建立最小化总成本的数学模型。利用蒙特卡洛仿真对总成本抽样,采用优化转换概率的花粉授粉算法对模型求解。数值实验证明,利用实时质量信息的视情维护策略相较于3类对比策略总成本更低,在高生产负荷系统下平均优化比例为9.61%,在低生产负荷系统下平均优化比例为10.71%。

基于稀疏码多址接入技术的可见光通信系统性能研究

5G新技术应用于可见光通信(Visible Light Communication,VLC)场景对系统容量以及频谱效率有了更高的要求,稀疏码多址接入(Sparse Code Multiple Access,SCMA)技术作为一种新型的非正交多址接入(Non-Orthgonal Multiple Access,NOMA)技术可作为解决方案。针对上述方案,搭建了VLC-SCMA系统,使得系统在相同的频谱资源下能够拥有更大的系统容量和频谱效率,同时为了降低系统复杂度,加快接收端进行多用户检测时的收敛速度,提出了基于串行改进下的部分外部信息传递的消息传递算法(Message Passing Algorithm Based on Serial Strategy for Partial External Information Transmission,SPEIT-MPA)。通过在迭代过程中设置门限值过滤掉携带信息量较少的外部信息点,利用串行改进使得算法迭代过程进一步简化。在VLC-SCMA系统中的仿真结果表明,对比原始算法,新算法可以在保证误码率(Bit Error Rate,BER)性能损失较少的前提下拥有更快的收敛速度,且算法复杂度随着信噪比(Signal to Noise Ratio,SNR)的增大明显降低。

基于扩张状态观测器的无人机云台系统控制算法

针对无人机(UAV)三轴云台增稳控制中变量耦合的问题,提出一种基于扩张状态观测器(ESO)的无人机云台系统控制算法。首先,建立了无人机机载云台期望角的姿态解算算法模型;其次,构建了无人机机载云台位置环和速度环的串级比例-积分-微分(PID)控制回路;最后,引入ESO对机载云台角速度项在线实时估计,解决角速度项由于高耦合、多外扰导致的难以直接测量的问题,并对各通道的控制输入进行补偿。实验结果表明,所提算法在无指令、有指令和综合任务场景下的角度均方根误差分别为0.2357°、0.6317°和0.9463°,与传统PID算法相比,所提算法的角度误差分别降低了69.43%、53.29%和50.43%。可见,所提算法对外界扰动的抗干扰能力更强,控制精度更高。

不完美串行干扰消除下多RIS辅助的NOMA系统中断性能

考虑到实际通信应用中不能实现完美的串行干扰消除(SIC,serialinterferencecancellation),研究了不完美SIC情况下多个智能反射面(RIS,reconfigurableintelligentsurface)辅助的非正交多址接入(NOMA,non-orthogonal multiple access)系统的中断性能和吞吐量。联合考虑直射链路和反射链路,利用Gamma分布近似表征多RIS辅助NOMA系统的信道系数,推导出用户中断概率的近似闭合表达式,并通过Monte-Carlo仿真进行验证,分析系统中断性能与不完美SIC、RIS个数及反射单元数等因素的关系。仿真结果表明,与单RIS辅助的NOMA系统和传统NOMA系统相比,在给定中断概率要求下,多RIS辅助系统所需的信噪比(SNR,signal-to-noise ratio)降低了14.2 dBm,说明了采用多个RIS可以有效地提升用户的中断性能和系统吞吐量,从而补偿不完美SIC带来的性能损失。

联合申遗导向下的江南水乡古镇文化遗产价值评价

由于缺少统一评估标准,各古镇分头治理,江南水乡古镇至今仍未纳入世界遗产名录。文章根据江南水乡古镇文化遗产特征和世界遗产突出普遍价值标准,构建价值评价体系,采用CRITIC赋权法进行赋值,加权叠加并导入三维矩阵模型,将江南水乡古镇分为8个区间和3个等级。优化的申遗名录包含13个一级古镇,较原名录增加12%上海市古镇,剔除价值不突出的10个古镇,增加5个价值突出的古镇,有助于减少行政区利益冲突,全面阐释江南水乡古镇突出普遍价值。

基于SRIO总线的光纤通信测试系统设计与实现

针对基于线阵电荷耦合元件(CCD)成像原理的调焦调平系统强实时性、高同步性及高数据率的特点,设计了一种基于串行RapidIO总线协议的光纤通信测试系统。该系统以现场可编程门阵列(FPGA)为控制核心,以光纤为传输介质,通过串行RapidIO总线协议完成对调焦调平系统性能验证过程中的指令控制和图像数据传输。基于双存储器(FIFO)缓冲的SRIO接口设计使得该测试系统具有较强的通用性和实用性。测试结果表明,该系统光纤接口数据传输速率达440 MB/s,能够满足调焦调平系统性能验证对数据传输速率及正确性的需求。

基于Cortex-M3的串口与CAN转换模块的设计与实现

针对采用控制器局域网络(CAN:Controller Area Network)总线的自动操舵系统和采用串口通讯的航海导航设备之间通讯的不匹配问题,设计了一种基于Cortex-M3嵌入式平台的通信转换模块,实现了串口与CAN总线数据的双向转换功能。同时对传统CAN收发器CTM1050存在的信号稳定性不足、波特率精准度低等问题,提出并实现了一种硬件电路的替代方案,提高了数据通讯的时效性和稳定性。基于CAN2.0B扩展帧,设计了自动操舵系统内部CAN总线协议。该协议可根据报文信息优先级分配标识帧,保证了总线数据的有序传输。实验结果表明,该通讯模块功能使用正常且通讯效果良好,具有一定通用性,可在多种需要转换的设备系统上推广使用。

SDI+IP混合架构的播总控系统设计

近年来,广播电视技术转型向网际互连协议(Internet Protocol,IP)化发展的进程逐渐加快,基于IP架构的电视技术系统必将取代传统串行数字接口(Serial Digital Interface,SDI)架构,成为未来电视技术的发展方向。对以互联网协议网关(Internet Protocol Gateway,IPG)作为关键设备搭建“SDI+IP”混合架构系统的设计方案进行深入分析,阐述电视技术系统从SDI向IP技术转型过程中尽可能实现平稳过渡的思路。

串行通信技术在变频器上应用的重要作用

在我国科技快速发展的背景下,工业领域也在高速发展,目前许多企业为实现智能化制造,在电气控制元件上预留了通信接口,这样一来就可以在变频器上应用串行通信技术,实现不同设备之间的网络通信。但是要想实现串行通信,还需要在变频器中对频率、电压进行调整。基于此,文章先简要阐述串行通信技术,然后分析如何利用串行通信技术实现变频器与可编程控制器之间的网络通信,希望能够为我国网络技术的发展提供有效帮助。

基于IO复用与时序控制的智能USB 3.0系统设计与实现

针对具备Andriod和Windows双系统的电子设备在使用通用串行总线(Universal Serial Bus,USB)接口与外设通信时出现的需重新插拔USB外设、切换后USB设备不识别率偏高等问题,通过对电路进行分析和设计优化,提出一种电源管理电路的参数取值计算方法。采用VL817、TUSB522P及FSUSB74芯片设计3路智能USB 3.0电路方案,通过HUB硬复位重置、D+/D-、SSTX/SSRX信号通道复用输入输出(Input Output,IO)控制以及时序控制USB设备切换顺序的方法,提高系统的抗干扰能力。实测数据显示,应用该电路系统后运行稳定,系统切换时USB外设的识别成功率显著高于同类产品,契合大规模产业化设计及应用需求。

The Gene Expression Patterns of Peripheral Blood Mononuclear Cells in Patients with Systemic Lupus Erythematosus

This study examined the gene expression patterns of peripheral blood mononuclear cells （PBMCs） in patients with systemic lupus erythematosus （SLE） by using serial analysis of gene expression （SAGE） technology. Following the construction of serial analysis of gene expression （SAGE） library of PBMCs collected from 3 cases of familial SLE patients, a large scale of tag Sequencing was performed. The data extracted from sequencing files was analyzed with SAGE 2000 V 4.5 software. The top 30 expressed genes of SLE patients were uploaded to http：//david.niaid.nih.gov/david/ease.htm and the functional classification of genes was obtained. The differences among those expressed gene were analyzed by Chi-square tests. The results showed that a total of 1286 unique SAGE tags were identified from 1814 individual SAGE tags. Among the 1286 unique tags, 86.8% had single copy, and only 0.2% tags had more than 20 copies. And 68.4% of the tags matched known expressed sequences, 41.1% of which matched more than one known expressed sequence. About 31.6% of the tags had no match and could represent potentially novel genes. Approximately one third of the top 30 genes were ribosomal protein, and the rest were genes related to metabolism or with unknown functions. Eight tags were found to express differentially in SAGE library of SLE patients. This study draws a profile of gene expression patterns of PBMCs in patients with SLE. Comparison of SAGE database from PBMCs between normal individuals and SLE patients will help us to better understand the pathogenesis of SLE.

Adjusting the Parameters of PI Regulator in All-electrical Tank Gun Control System by Computer Program

Both the traverse subsystem and the elevation subsystem of the all-electrical tank gun control system are composed of electrical drive control system respectively. The parameters of PI regulator in these electrical drive control systems affect the performance of the control system seriously. Up to now, there is not a simple and practical method for choosing regulator parameters, which are usually determined by repeated and continual readjustment. This method is low efficient, and the parameters got are not always optimal. A method for on-line adjusting the parameters of PI regulator in the electrical drive control system by computer program is introduced in this paper. The function of adjusting PI parameters of the electrical drive control system is realized by PC program written by VC++ and controlling program written by assemble language and by the communication between PC and DSP completed by the control MSCOMM in VC++6.0. The method as mentioned above which is applied for an all-electrical tank gun control system under development is proved very available, a better performance might be obtained for the all-electrical tank gun control system easily.

Windows and Fieldbus Based Software Computer Numerical Control System

Computer numerical control(CNC)system is the base of modern digital and intelligent manufacturing technolo- gy.And opened its architecture and constituted based on PC and Windows operating system(OS)is the main trend of CNC sys- tem.However,even if the highest system priority is used in user mode,real-time capability of Windows(2000,NT,XP)for applications is not guaranteed.By using a device driver,which is running in kernel mode,the real time performance of Windows can be enhanced greatly.The acknowledgment performance of Windows to peripheral interrupts was evaluated.Harmonized with an intelligent real-time serial communication bus(RTSB),strict real-time performance can be achieved in Windows platform. An opened architecture software CNC system which is hardware independence is proposed based on PC and RTSB.A numerical control real time kernel(NCRTK),which is implemented as a device driver on Windows,is used to perform the NC tasks.Tasks are divided into real-time and non real-time.Real-time task is running in kernel mode and non real-time task is running in user mode.Data are exchanged between kernel and user mode by DMA and Windows Messages.

Study on the Multi-Sensing System Based on the Tin Oxide pH Electrode

In this study,the multi-sensing system based on the tin oxide pH electrode for the ion-determination was presented. With the advantages of the real-time supervisory control apparatus,the measured values could be displayed on the liquid crystal display (LCD) immediately.In this study,the basic sensor was the tin oxide pH electrode,which was fabricated by radio frequency (r.f.) sputtering system on the indium tin oxide (ITO)/glass substrate.Moreover,the major blocks of the system consist of the tin oxide electrode-based ion selective electrodes (ISEs),an analog front-ended readout circuit,a microcontroller with built-in analog to digital (A/D) converter.In addition,by the embedded system design,the measurement results can be transmitted to a portable system or computer through the Universal Serial Bus (USB) and Universal Asynchronous Receiver Transmitter (UART) interface immediately.According to the experimental results,the multi-sensing system has high performance and reliability for pH,K^+,and Na^+ detection.

基于单片机的编码设计

ARM(Advanced RISC Machines)处理器是32位处理器,性价比很高,也可使用16位指令集,在具备32位系统优势的同时减少了代码数量,提高了编程效率。ARM具有精度高、体积小、功耗低、集成度高等优点,可作为旋转变压器的解算模块,还可用于伺服系统的位置反馈检测模块。基于此,文中设计一种基于ARM微处理器的小型双轴旋转变压器的编码模块。采用轴角计算芯片测量元件输出的角度信息;再将采集的角度值送入处理器进行处理,经过编码以串口通信的方式发送给伺服单元,实现对角度变化的精准控制。