42927366
UML Modelling Web Applications via Formal Concept Analysis
16604369
Reusing legacy COBOL code with UML collaboration diagrams via a Wide Spectrum Language
Many legacy systems were developed in COBOL, which still play an important role in business. It is an unavoidable issue for organisations to maintain or replace these COBOL systems. In order to make a better use of these legacy COBOL systems, research on modelling and reusing COBOL code are significant. This paper presents an approach to modelling legacy COBOL code with UML collaboration diagrams via a Wide Spectrum Language (WSL). Firstly, legacy COBOL code is transferred into WSL, which is an intermediate language. Secondly, WSL representation is restructured to eliminate GOTO statements. Then an object concept model is created by operating WSL representation. Finally, the collaboration diagrams are constructed based on this object concept model. These collaboration diagrams express the dynamic behaviour of the system, using the structural class and relationship elements of the model, and facilitate engineers to understand and reuse legacy COBOL code.
13014692
Extracting Reusable Object-Oriented Legacy Code Segments with Combined Formal Concept Analysis and Slicing Techniques for Service Integration
Web services, together with service-oriented architectures, are promising integration technology to facilitate legacy system Webification and evolution. However, a service-oriented re-engineering process is still essential for legacy systems to survive in the service-oriented computing environment. In this service-oriented re-engineering process, understanding and reusing object-oriented code turn to be important activities. In this paper, we proposed a comprehensive approach to support the extraction and integration of reusable object-oriented legacy code. In the extraction phase, formal concept analysis, which is a general and flexible technique for recovering structural design information, and inter-procedural program slicing are adopted as main reverse engineering techniques to recover reusable object-oriented code. In the integration phase, service packaging processes are presented in details. Our approach produces extracted components with core legacy object-oriented code function in Web services by wrapping underlying computing models with XML
18861911
Service Identification and Packaging in Service Oriented Reengineering
With the adoption to Web service technologies, more and more existing non-service-oriented software systems turn to be legacy systems. They require a service-oriented reengineering process in order to survive in serviceoriented computing environment. In this paper, we present an architecture-based service-oriented approach to support service-oriented reengineering. It integrates and reuses software components as services over Internet by wrapping underlying computing models with XML. Service identification and service packaging processes are described in details, which are the keys to serviceoriented reengineering. Target services are defined according to service identification, which is based on a comparison of analyses in both problem domain and legacy systems. Clustering techniques are applied in service identification process to analyse recovered architectural information and to identify related modules. Service packaging is benefit from architecture-based development and reuse.
10032867
Incubating services in legacy systems for architectural migration
Legacy systems are valuable assets for organisations. They continuously evolve with new emerged technologies in rapidly changing business environment. Web services, together with service-oriented architectures, facilitate legacy system webification and evolution in service-oriented computing environment. Traditional approaches to integrate legacy systems with Web service technology are wrapping a legacy system as a black-box without adequate system understanding. In this paper, we proposed a reengineering approach which applies an improved agglomerative hierarchical clustering algorithm to restructure legacy code and to facilitate legacy code extraction for Web service construction. It supports service identification and service packaging and archives legacy system migration into service-oriented architectures by providing functional legacy code as Web services.
14080651
GcpSensor: a CPU performance tool for grid environments
In grid computing environments, CPU performance discovery and allocation is a serious issue. Before they run their applications, grid users need to choose grid nodes based on available CPUs performance. Hence a tool is needed for measuring CPUs performance. To address this need, GcpSensor (grid CPU performance sensor) was developed. GcpSensor runs a typical benchmark program in every grid node to measure CPU performance and returns a metric named WMFLOPS which can be used to compare different CPUs performance directly. An algorithm, which can choose a moderate computation cost dynamically, is designed to ensure that every test is comprehensive and the added overhead is comparatively small. Our experiments have proved that GcpSensor can indicate the CPU performance sensitively and that users can use the GcpSensor data to compare different CPUs performance straightforward, thus the accuracy and efficiency for selecting computing resources are increased.
8951856
Model-based head pose tracking with stereovision
We present a robust model-based stereo head tracking algorithm that operates in real time on a commodity PC. The use of an individualized three-dimensional head model, coupled with the epipolar constraint from the stereo image pair greatly improves the robustness of the tracking. Experimental results have shown that our method is able to track all the six degrees of freedom of the rigid part of head motions, over an extended period of time, in the presence of large angular and translational head motions, partial occlusions, and/or dramatic facial expression changes. Applications include human-computer interaction and eye-gaze correction for videoconferencing.
29297629
An Application of Fuzzy Cluster analysis to Matchmaking in Middle Agents
6522316
Visual echo cancellation in a projector-camera-whiteboard system
We propose to incorporate a whiteboard into a projector-camera system. The whiteboard serves as the writing surface (input) as well as the projecting surface (output). The ability to write and draw on top of computer-projected content opens up many new opportunities for real-time collaborations between people located on-site and remotely. Such applications inevitably require extracting handwritings from video images that contain both handwritings and the projected content. By analogy with echo cancellation in audio conferencing, we call this problem visual echo cancellation. This paper presents one approach to accomplish the task. Our visual echo cancellation algorithm estimates the incident light and derives the surface albedo based on both incident light and reflection. By estimating the albedo, we can extract the writings and recover their colors. Our approach includes two basic components of projector-camera systems: geometric calibration and color calibration. The first one solves the mapping between the position in the camera view and the position in the projector screen, while the second one solves the mapping between the actual color of the projected content and that seen by the camera.
9741831
A performance model for fine-grain accesses in UPC
UPC's implicit communication and fine-grain programming style make application performance modeling a challenging task. The correspondence between remote references and communication events depends on the internals of the compiler and runtime system. This correspondence is often hidden from application developers. Aggressive optimizations allowed by the relaxed memory consistency model further blur this correspondence by transforming code structure. A modeling approach based on UPC platform benchmarking and code analysis is proposed. This approach abstracts a UPC platform according to its potential to apply a few common optimizations, then divides remote references in the application code into groups, based on a dependence analysis, that are amenable to each optimization. Each group is associated with a cost, obtained via benchmarking each potential optimization. The aggregated cost of these groups is the predicted cost of the application. Three simple UPC applications modeled using this approach usually yielded performance predictions within 15 percent of actual running times
11664234
Secure Name Service: A Framework for Protecting Critical Internet Resources
We propose a novel Secure Name Service (SNS) framework for protecting critical Internet resources from unauthorized accesses, denial of service (DoS) and other attacks. The key idea is to enforce packet-origin authentication through resource virtualization and utilize dynamic name binding for protecting servers under attacks and improving service availability. Different from static network-level security schemes such as IPsec and VPN, SNS is able to dynamically bind the names of critical resources at the service level, which allows us to actively protect the service resources through a distributed filtering mechanism built on authenticated packet forwarding paths. Our prototype implementation of authenticated packet forwarding components on Pentium 4 Linux machines demonstrates that regular Linux platforms are sufficient to support SNS authenticated packet forwarding on 100Mbps or lGbps LANs.