A design framework for e-business infrastructure integration andresource management

One of the challenges faced by an enterprise with employees in multiple locations is to design a high performance, secure and interoperable distributed computing system (DCS) to interconnect all locations and operations. The problem is computationally hard; hence, subcomponents of it have been studied in detail. These tend to be complex, predominantly theoretical, and somewhat limited from a practical standpoint in terms of providing an integrated solution. Researchers have indicated the need to study the integrated DCS design problem. We merge the complex components and demonstrate that this intrinsically hard problem can be modeled using a component-wise iterative approach. We present a methodology for resource planning and integration that is simple and practical, and can be applied to real-life problems. The methodology includes performance, cost, security and interoperability issues as DCS design objectives. It distributes data and application systems across multiple locations, and aids in security and interoperability configuration, such that the overall design objectives are satisfied. This is one of the first attempts at combining the various components of DCS design and applying it to a real-life problem. The design framework has been successfully used to design a distributed training system for a large, geographically dispersed organization     

Integrating simulation and optimization of manufacturing systems

This paper presents the ongoing development of a modeling methodology and a tool (the so-called simulation integrated system with modeling and optimization (SISMO) solver) that permits manufacturing systems to be both simulated and optimized according to several improvement strategies. We point out that the different steps of modeling, simulating, and optimizing uses the same integrated formalism and environment. A major point of this methodology and tool is the original decision-making mechanism over a hierarchy of complex discrete systems that model the real world. For the SISMO platform to be validated, we applied it to an actual highly constrained discrete-continuous scheduling problem. This study on a real-life problem has systematically led to improvements.     

Enterprise Ontologies for Planning and Integration of Business: A Pragmatic Approach

Enterprise ontologies (EOs), introduced in the mid 1990s, were expected to have a significant impact on enterprise computing, especially integration. However, despite a great deal of academic research on EOs, the actual use of EOs in real-life integration and planning projects is almost nonexisting. This paper describes an approach to build and use EOs for information system (IS) planning and integration projects with particular focus on real-life eBusiness applications. The approach is based on firsthand practical insights gained through construction and use of an IS planning and integration environment that needs to capture business processes, enterprise applications, integration technologies, and computer-communication platforms. The planning model with the aforementioned information is based on an EO and is populated by a set of intelligent advisors while they guide the users through various stages of the planning process. This ontology has been used to support over 40 real-life business scenarios in the telecom, manufacturing, financial services, retail, healthcare, and insurance industries. The practical contribution of this paper is that it connects ontologies to the practice of IS planning and integration, links ontologies to decisions such as enterprise application selection, and provides tools for automatically creating and maintaining ontology repositories.     

Engineering Open Complex Agent Systems: A Case Study

Open complex agent systems (OCAS) are becoming increasingly important in constructing problem-solving systems for enterprise applications. are challenging because they present very high system complexities involving human users and interactions with a changing environment. The existing agent-oriented software engineering (AOSE) approaches have trouble in engineering OCAS because of a number of deficiencies, e.g., lacking the capability of handling system dynamics analysis. This paper introduces an effective AOSE approach, i.e., organization- and service-oriented system analysis and design (OSOAD). It is used to extract and model system members and design a real-life OCAS system called financial trading rule automated development and evaluation (F-Trade). Through the case studies of visual and formal modeling and design of major organizational members, relations, and subsystems in F-Trade, this paper demonstrates the effective mechanisms and capabilities of the OSOAD approach. System implementation and evaluation results further show that OSOAD provides comprehensive AOSE support for engineering real-world open complex agent organizations.     

Accelerated stress testing of a-Si:H pixel circuits for AMOLED displays

Electronics reliability testing is traditionally carried out by accelerating the failure mechanisms using high temperature and high stress, and then predicting the real-life performance with the Arrhenius model. Such methods have also been applied to organic light-emitting diode (OLED) testing to predict lifetimes of tens of thousands of hours. However, testing the active matrix OLED thin-film transistor (TFT) backplane is a unique and complex case where standard accelerated testing cannot be directly applied. This is because the failure mechanism of pixel circuits is governed by multiple material and device effects, which are compounded by the self-compensating nature of the circuits. In this paper, we define and characterize the factors affecting the primary failure mechanism and develop a general method for accelerated stress testing of TFT pixel circuits in a-Si AMOLED displays. The acceleration factors derived are based on high electrical and temperature stress, and can be used to significantly reduce the testing time required to guarantee a 30 000-h display backplane lifespan.     

基于响应面分析的RFID应用部署测试优化设计

RFID技术近年来取得快速发展,成为物联网的关键技术之一.利用试验设计方法对RFID应用部署测试进行了优化,借助正交试验设计方法在多因子多水平的条件下迅速制定测试计划,了解组合测试中多因子对测试结果影响的主次因素和规律,有效地解决组合爆炸问题.还通过多元线性回归分析和最小二乘估计建立响应面方程拟合多个自变量与因变量之间的关系,分别通过正交试验、零水平点拟合试验和最速上升试验快速获得优化方案,从而为在复杂环境条件下提高RFID系统性能,预测部署效果,优化部署条件提供可靠的保证.     

Modeling Mobility in Cooperative Ad Hoc Networks

This paper addresses issues concerned with design and managing of mobile ad hoc networks. We focus on self-organizing, cooperative and coherent networks that enable a continuous communication with a central decision unit and adopt to changes in an unknown environment to achieve a given goal. In general, it is very difficult to model a motion of nodes of a real-life ad hoc network. However, mobility modeling is a critical element that has great influence on the performance characteristics of a cooperative system. In this paper we investigate a novel approach to cooperative and fully connected networks design. We present an algorithm for efficient calculating of motion trajectories of wireless devices. Our computing scheme adopts two techniques, the concept of an artificial potential field and the concept of a particle-based mobility. The utility and efficiency of the proposed approach has been justified through simulation experiments. The results of presented case studies show a wide range of applications of our method starting from simple to more complex ad hoc networks.     

Formal verification of component-based designs

Embedded systems are becoming increasingly common in our everyday lives. As technology progresses, these systems become more and more complex, and designers handle this increasing complexity by reusing existing components (Intellectual Property blocks). At the same time, the systems must fulfill strict requirements on reliability and correctness. This paper proposes a formal verification methodology which smoothly integrates with component-based system-level design using a divide and conquer approach. The methodology assumes that the system consists of several reusable components, each of them already formally verified by their designers. The components are considered correct given that the environment satisfies certain properties imposed by the component. The methodology verifies the correctness of the glue logic inserted between the components and the interaction of the components through the glue logic. Each such glue logic is verified one at a time using model checking techniques. Experimental results have shown the efficiency of the proposed methodology and demonstrated that it is feasible to apply such a verification methodology on real-life examples.     

智慧企业中的智慧搜

现代企业除了面临复杂的生产环境和网络环境外,还需积极应对和处理随之产生的海量数据。这些数据服务于企业发展是智慧企业的目的之一。基于企业各个环节可能产生的各种数据类型和对应的搜索技术,智慧搜索旨在为智慧企业的实现与发展增加一种新的智慧服务。通过实例来阐述智慧搜索的内涵和外延,以及智慧搜索能为企业带来的不同级别的服务和相应的挑战。     

Modeling microwave power structures based on k-furcated waveguides arbitrarily filled with materials by modal techniques.

Waveguide structures are very popular in the microwave power industry due to their power handling capabilities. Modal expansion of the waveguide fields and application of the circuit theory allow for the division of a complex device into several simpler sections which can be analyzed separately with the best suited method. The modal techniques can be divided into two groups--those which analyze junctions or discontinuities and those which examine propagation characteristics. In this paper, a review of modal techniques for high power applications is given. Modal expansion of the fields in the waveguides is then performed and applied to modeling of k-furcated waveguides. The modal analysis based on the Coupled Mode Method is described for the waveguides partially filled with isotropic materials. A hybrid modal analysis coupled with Finite Element Method suitable for more complex waveguide structures is also described. Computational results obtained for some real-life microwave devices are presented. Excellent agreement was found when comparing the results with those generated with a commercial FDTD simulator demonstrates the validity and reliability of the proposed method.     

On the (Un)Reliability of TCP Connections: The Return of the End-to-End Argument

This paper discusses the dangers of relying solely on TCP reliability when implementing dependable computing systems, even when those systems are designed to work over a LAN environment. The discussion includes a real-life example from our recent experiences in developing such a system.     

Multicast Routing in Wireless Mesh Networks: Minimum Cost Trees or Shortest Path Trees?

There exist two fundamental approaches to multicast routing: shortest path trees (SPTs) and minimum cost trees (MCTs). The SPT algorithms minimize the distance (or cost) from the sender to each receiver, whereas the MCT algorithms minimize the overall cost of the multicast tree. Due to the very large scale and unknown topology of the Internet, computing MCTs for multicast routing in the Internet is a very complex problem. As a result, the SPT approach is the more commonly used method for multicast routing in the Internet, because it is easy to implement and gives minimum delay from the sender to each receiver, a property favored by many real-life applications. Unlike the Internet, a wireless mesh network (WMN) has a much smaller size, and its topology can be made known to all nodes in the network. This makes the MCT approach an equally viable candidate for multicast routing in WMNs. However, it is not clear how the two types of trees compare when used in WMNs. In this article we present a simulation-based performance comparison of SPTs and MCTs in WMNs, using performance metrics, such as packet delivery ratio, end-to-end delay, and traffic impacts on unicast flows in the same network.     

Reliability aspects of microsensors and micromechatronic actuators for automotive applications

In modern cars microsensors and micromechatronic actuators play an essential and still increasingly important role as the interface between the vehicle with its complex functions of motor management, chassis systems, safety as well as comfort and convenience on the one hand and the respective electronic control units on the other hand. They have to fulfill their task in a harsh environment over the entire lifetime of an automobile. Therefore reliability aspects have moved more and more into the focus of engineering and research activities in microsystem technology. A methodical procedure is described that allows reliability issues to be approached efficiently. The implementation of the methodology is illustrated with real-life examples of reliability aspects of hot film mass air flow sensors, inertial sensors as well as piezoelectric actuators.     

Applicability of Hadamard relaxation method to MMW and THz Imaging with compressive sensing

Compressive sensing (CS) is widely considered a promising method for millimeter wave (MMW) and terahertz (THz) imaging, especially in security screening. In many real-life application scenarios, a CS reconstruction algorithm has to be simultaneously robust, noise-tolerant and fast to be of practical use. However, a lot of CS reconstruction algorithms are not designed aiming at such overall performance, preventing them to become applicable in commercial imaging systems. Having investigated some CS algorithms, we find that Hadamard relaxation method is a potential candidate for commercial CS imaging. By using MATLAB, we study Hadamard relaxation method focusing on its under-sampling ratio, tolerance to noise and efficiency. Comparisons with several other CS algorithms are made using the available data in references. The results demonstrate that the overall performance of Hadamard relaxation method is among the best for real-life and real-time applications of MMW and THz imaging.     

从噪声中恢复瞬态信号的Gabor级数法

该文研究了从噪声中恢复原瞬态信号问题。根据瞬态信号和噪声的Gabor系数在时-频平面上分布不同的特点,借用假设检验理论,提出了一种恢复被噪声污染的原瞬态信号的Gabor级数方法,进行了计算机仿真和对实际信号的处理。     

遗传算法的噪声干扰数字图像分类性能评价

针对现实中各种噪声干扰的数字图像识别分类的问题,提出了基于遗传算法优化的BP神经网络和支持向量机神经网络两种方案,先在无噪声干扰情况下建模,然后加入人工噪声模拟现实中的噪声干扰。结果表明,遗传算法优化后的支持向量机网络方案具备更好的抗噪声干扰能力,在噪声干扰数字图像分类中具有更高应用价值。     

Spectral spurs due to quantization in Nyquist ADCs

This paper presents intuitive yet quantitative insights into the harmonics of analog-to-digital converter (ADC) output spectra. It derives the spectral signatures associated with imperfections in practical ADCs. This understanding leads to remedies based on architecture and time-averaging, which are combined to propose a calibration-free pipeline CMOS ADC that simulations show is capable of better than 100-dB spurious-free dynamic range in the presence of real-life imperfections.     

Optimization of a K-on-N configuration

A new class of redundant systems called the K-on-N configuration is introduced here. Realistic design features are developed for the available resources to build a highly reliable system. An easily programmed algorithm due to Lawler and Bell is adapted to solve the optimization problem. The method is applied for reliability improvement of a real-life system problem.