Design and performance evaluation of a novel robotic catheter system for vascular interventional surgery

Vascular interventional surgery (VIS) is an effective treatment method for vascular diseases. However, there are many problems in traditional VIS, such as surgeons are radiated by X-ray, the lack of well skilled surgeons, the security of the surgery will be reduced due to the Surgeons’ fatigue, high risk of the surgery. To solve these problems, a robotic catheter system is needed to protect the surgeons and enhance the safety of the surgery. In this paper, a novel robotic catheter system with master–slave structure for VIS has been developed. This system is designed with the consideration of the operation method in traditional VIS, which allows the surgeon to operate a real catheter on the master side, then the surgeon make full use of the natural catheter manipulation experience and skills obtained in conventional catheter operation. The salve manipulator operates the catheter insert into the blood vessel with following the operation of the surgeon, and the operating force of the salve manipulator is detected. On the master side, a novel damper-based magnetorheological (MR) fluid is designed to realize the force feedback, which is also used to reappear the operation force from the salve manipulator. The damper connected directly with real catheter is a piston structure using the MR fluid to realize the force feedback. It can transmit the feedback force to surgeon’s hand through the operating catheter connected with damper, which seems that the surgeon operates the catheter beside the patient. The operating transparency of the developed system has been enhanced. The mechanism of the developed system has been introduced in detail. Performance evaluation experiments for the developed robotic catheter system have been done. The experimental results indicated that the developed robotic catheter system is fit for VIS.     

列车枕簧自动控制系统的设计和实现

车辆检修质量直接影响列车的正点安全运行。该系统采用了当今先进的集成控制——主从分布式控制系统,由欧姆龙公司的PLC完成对枕簧自动检测、分检系统的控制。该文介绍了枕簧检测、喷漆、烘干、分拣控制系统的组成,工作原理,控制方式及程序设计思想。实际应用证明了该系统提高了检测精度、降低了劳动强度、保证列车安全运行。     

Computer architecture for intelligent robots

This article proposes a computer architecture suitable for intelligent robots, especially for self-contained intelligent mobile robots. The main principles proposed by the authors are: (1) The robot should be a multiprocessor system with a master, several slave modules and a console. A simple star connection is employed. (2) The master carries user's programs written in a high level language with which a programmer is able to use all basic functions in the robots. It should have a special purpose operating system. (3) Each module is an independent microcomputer system loosely coupled to the master and dedicated to an elementary function such as manipulation, locomotion, sensing, or planning. (4) A serial TTL level or RS232C interface is employed between the master and each module. Two self-contained robots, Yamabico 9 and 10, constructed under these design principles have demonstrated the effectiveness of this proposed architecture.     

高校多媒体教室计算机系统的科学架构

针对美国东部时间2014年4月8日午夜零点已全面停止Windows XP视窗操作系统安全更新,不再修补XP系统的安全漏洞,安装XP系统的用户面临极大的风险。由于国内各高等学校多媒体教室计算机操作系统大多使用的是Windows XP,面对XP的停服,不再保护教室计算机系统的安全,各种漏洞将不断出现,面临病毒入侵的风险,如不尽快采取措施,升级多媒体教室计算机操作系统,将会影响多媒体教学工作。为做好多媒体教室计算机操作系统的升级工作,使教师尽快掌握Windows 7操作系统的使用技巧,更好地服务于高校多媒体教学,故必须对高校多媒体教室计算机系统重新进行科学架构。     

Control and synchronization of chaotic systems using a novel indirect model reference fuzzy controller

This paper presents a robust indirect model reference fuzzy control scheme for control and synchronization of chaotic nonlinear systems subject to uncertainties and external disturbances. The chaotic system with disturbance is modeled as a Takagi–Sugeno fuzzy system. Using a Lyapunov function, stable adaptation laws for the estimation of the parameters of the Takagi–Sugeno fuzzy model are derived as well as what the control signal should be to compensate for the uncertainties. The synchronization of chaotic systems is also considered in the paper. It is shown that by the use of an appropriate reference signal, it is possible to make the reference model follow the master chaotic system. Then, using the proposed model reference fuzzy controller, it is possible to force the slave to act as the reference system. In this way, the chaotic master and the slave systems are synchronized. It is shown that not only can the initial values of the master and the slave be different, but also there can be parametric differences between them. The proposed control scheme is simulated on the control and the synchronization of Duffing oscillators and Genesio–Tesi systems.     

Impact of forecasting error on the performance of capacitated multi-item production systems

A computer model is built to simulate master production scheduling activities in a capacitated multi-item production system under demand uncertainty and a rolling time horizon. The output from the simulation is analyzed through statistical software. The results of the study show that forecasting errors have significant impacts on total cost, schedule instability and system service level, and the performance of forecasting errors is significantly influenced by some operational factors, such as capacity tightness and cost structure. Furthermore, the selection of the master production schedule freezing parameters is also significantly influenced by forecasting errors. The findings from this study can help managers optimize their production plans by selecting more reasonable forecasting methods and scheduling parameters, thus improving the performance of production systems.     

Batch production control in a computer integrated manufacturing environment

Since unit level control systems have already been widely implemented in the chemical industry, it has become abundantly clear that the next levels of application lie in supervisory control and scheduling. This is particularly true for the chemical processing industry, operating batchwise with multi-product and multi-purpose characteristics. A ‘flexible schedule’ (FLESCHE) concept providing the link between operations scheduling and the recipe-driven batch operatioon with its basic instrumentation and control system is being developed and implemented in a computer integrated manufacturing environment. The FLESCHE system incorporates an integrated decision-making framework which includes all the relevant decision functions in a multi-level hierarchy: optimal plant-wide resources coordination, demand management, plant-wide operations scheduling and plant retrofitting on the one hand, as well as master recipe adaptation, batch rerouting and schedule adaptation in response to short-time, unplanned operational disturbances, on the other. A summary of the main characteristics, methodology and present applications of the system is provided. Actual limitations and future extensions are also discussed.     

基于生产计划排单的遗传算法的优化与应用

ERP是当今国际上先进的企业管理模式，其核心是计划体系，包括主生产计划、采购计划、车间作业计划等。车间作业计划的管理目标是按物料需求计划的要求，按时、按质、按量和低成本地完成加工制造任务。该文探讨了遗传算法在车间作业计划安排中的应用，主要是针对Flow Shop的调度问题，给出了包括建模、编码、选择、交叉、变异和适应性函数等的具体算法，并在最后给出了自适应算法、混合遗传算法等优化算法。经仿真算例分析，该算法取得较理想的效果。     

比喻教学法在操作系统原理教学中的应用

本文针对操作系统课程内容抽象、晦涩的特点提出比喻教学法,使学生从比喻中深刻理解和熟练掌握相关概念和原理。结合进程管理、存储管理、设备管理相关知识,通过分析实际案例对比喻教学法进行阐述。实践证明,比喻教学法在教学探索中效果很好。     

基于DSP的望远镜液压控制系统

依靠液压系统支撑的天文望远镜在正常工作过程中往往要求其油(液)压保持在某一稳定值。为此,设计了基于DSP的液压模糊控制系统。该系统采用TMS320F2812 DSP芯片作为微处理器,控制相应的外围电机驱动电路;利用传感器测得的油压信号与目标值之间的偏差,经模糊控制器计算处理后输出相应占空比的PWM波形,从而调节油泵电机的运行频率,以实现液压系统油压的稳定。现场运行结果表明,该系统可以有效消除外界环境因素的干扰,保证了油压的稳定。