Trust management towards service-oriented applications

In service-oriented computing (SOC) environments, service clients interact with service providers for services or transactions. From the point view of service clients, the trust status of a service provider is a critical issue to consider, particularly when the service provider is unknown to them. Typically, the trust evaluation is based on the feedback on the service quality provided by service clients. In this paper, we first present a trust management framework that is event-driven and rule-based. In this framework, trust computation is based on formulae. But rules are defined to determine which formula to use and what arguments to use, according to the event occurred during the transaction or service. In addition, we propose some trust evaluation metrics and a formula for trust computation. The formula is designed to be adaptable to different application domains by setting suitable arguments. Particularly, the proposed model addresses the incremental characteristics of trust establishment process. Furthermore, we propose a fuzzy logic based approach for determining reputation ranks that particularly differentiates new service providers and old (long-existing) ones. This is further incentive to new service providers and penalize poor quality services from service providers. Finally, a set of empirical studies has been conducted to study the properties of the proposed approaches, and the method to control the trust changes in both trust increment and decrement cases. The proposed framework is adaptable for different domains and complex trust evaluation systems.

Agent-based reconfigurable architecture for real-time object tracking

Most conventional object tracking algorithms are implemented on general-purpose processors in software due to its great flexibility. However, the real-time performance is hard to achieve due to the inherent characteristics of the sequential processing of these processors. To tackle this issue, a reconfigurable system-on-chip (rSoC) platform with microprocessors and FPGAs is applied in this paper. To simplify the hardware/software interface, a Belief–Desire–Intention (BDI)-based multi-agent architecture is proposed as the unified framework. Then an agent-based task graph and two heuristic partitioning methods are proposed to partition the hardware and software on an rSoC platform. Compared to the module-based architecture, this BDI-based multi-agent architecture provides more efficiency, flexibility, autonomy, and scalability for the real-time tracking systems. A particle swarm optimization (PSO)-based object detection and tracking algorithm is applied to evaluate the proposed architecture. Extensive experimental results of object tracking demonstrate that the proposed architecture is efficient and highly robust with real-time performance.     

Reducing control points in lofted B-spline surface interpolation using common knot vector determination

A new algorithm for reducing control points in lofted surface interpolation to rows of data points is presented in this paper. The key step of surface lofting is to obtain a set of compatible B-spline curves interpolating each row. Given a set of points and their parameterization, a necessary and sufficient condition is proposed to determine the existence of interpolating B-spline curves defined on a given knot vector. Based on this condition, we first properly construct a common knot vector that guarantees the existence of interpolating B-spline curves to each row of points. Then we calculate a set of interpolating B-spline curves defined on the common knot vector by energy minimization. Using this method, fewer control points are employed while maintaining a visually pleasing shape of the lofted surface. Several experimental results demonstrate the usability and quality of the proposed method.     

A numerically stable fragile watermarking scheme for authenticating 3D models

This paper analyzes the numerically instable problem in the current 3D fragile watermarking schemes. Some existing fragile watermarking schemes apply the floating-point arithmetic to embed the watermarks. However, these schemes fail to work properly due to the numerically instable problem, which is common in the floating-point arithmetic. This paper proposes a numerically stable fragile watermarking scheme. The scheme views the mantissa part of the floating-point number as an unsigned integer and operates on it by the bit XOR operator. Since there is no numerical problem in the bit operation, this scheme is numerically stable. The scheme can control the watermark strength through changing the embedding parameters. This paper further discusses selecting appropriate embedding parameters to achieve good performance in terms of the perceptual invisibility and the ability to detect unauthorized attacks on the 3D models. The experimental results show that the proposed public scheme could detect attacks such as adding noise, adding/deleting faces, inserting/removing vertices, etc. The comparisons with the existing fragile schemes show that this scheme is easier to implement and use.     

Combining the Hanning windowed interpolated FFT in both directions

The interpolated fast Fourier transform (IFFT) has been proposed as a way to eliminate the picket fence effect (PFE) of the fast Fourier transform. The modulus based IFFT, cited in most relevant references, makes use of only the 1st and 2nd highest spectral lines. An approach using three principal spectral lines is proposed. This new approach combines both directions of the complex spectrum based IFFT with the Hanning window. The optimal weight to minimize the estimation variance is established on the first order Taylor series expansion of noise interference. A numerical simulation is carried out, and the results are compared with the Cramer-Rao bound. It is demonstrated that the proposed approach has a lower estimation variance than the two-spectral-line approach. The improvement depends on the extent of sampling deviating from the coherent condition, and the best is decreasing variance by 2/7. However, it is also shown that the estimation variance of the windowed IFFT with the Hanning is significantly higher than that of without windowing.     

基于MCS-51单片机的洗衣机控制系统设计

根据洗衣机的控制要求,从功能要求、硬件设计、软件设计三个方面描述了一个以MCS-51单片机为控制核心的洗衣机控制系统。给出了硬件线路框图和相关的控制程序流程图。     

均质机智能控制系统设计

针对传统均质机的缺点,设计了一套基于 HMI、PLC、变频器的控制系统.实现了对均质机的自动控制.针对均质机加热工作采用夹层注油间接加热方式具有滞后大的特点,提出一种基于三菱FX2N系列PLC的专家PID的控制算法.有效解决传统均质机控制系统加热控制时温度超调量大、加热控制时间过长的问题.本设计已经应用到了实际生产中,取得良好效果.     

专家系统控制在掰手腕机器人中的应用

掰手腕机器人既可以作为一种娱乐装置,也可以用来作为一种锻炼装置增强手腕、手臂的肌肉力量。考虑到系统的非线性和复杂性,提出专家系统来解决机械臂的运动控制问题。首先介绍了掰手腕机器人系统的整体结构,然后引入专家系统控制,最后讨论了在此基础上的实验和结果。实验结果证明该控制算法有效、可行。应用专家系统控制策略,使得该系统克服了干扰和不确定现象,并具有良好的适应性。     

基于组播和P2P的文件分发管理模块的设计与实现

本文对CNGI研究课题"组播与P2P相结合的文件分发系统"进行了简要介绍.通过对该系统文件管理模块的总体设计和详细设计,实现了基于IPv6组播与P2P技术的结合.该系统借助JxTA平台实现P2P的基本功能:节点搜索、节点资源搜索、节点间的通讯和文件的统一管理等,实现了尽量利用可靠的组播并利用P2P实现跨组播域的信息传输.最后通过对管理模块在不同环境下的测试数据进行分析,表明该设计思想的有效性.