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
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.
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.
35739145
A Flexible Algorithm for Extracting Periodic Signals
In this paper, we propose a flexible two-stage algorithm for extracting desired periodic signals. In the first stage, if the period and phase information of the desired signal is available (or can be estimated), a minimum mean square error approach is used to coarsely recover the desired source signal. If only the period information is available (or can be estimated), a robust correlation based method is proposed to achieve the same goal. The second stage uses a higher-order statistics based Newton-like algorithm, derived from a constrained maximum likelihood criteria, to process the extracted noisy signal as cleanly as possible. A parameterized nonlinearity is adopted in this stage, adapted according to the estimated statistics of the desired signal. Compared with many existing extraction algorithms, the proposed algorithm has better performance, which is confirmed by simulations.
46660413
Optimal Scheduling Algorithms in WDM Optical Interconnects with Limited Range Wavelength Conversion Capability
In this paper we study optimal scheduling algorithms to resolve output contentions in time slotted WDM optical interconnects with wavelength conversion ability. We consider the general case of limited range wavelength conversion with arbitrary conversion capability, as it is easier to implement and more cost effective than full range wavelength conversion, and also includes full range wavelength conversion as a special case. We consider the conversion scheme in which each wavelength can be converted to multiple wavelengths belongs to an interval and the intervals for different wavelengths are “ordered”. To be specific, the conversion range of λ i can be written as [begin(i), end(i)], where begin(i) and end(i) are positive integers and if i < j then begin(i) ≤ begin(j) and end(i) ≤ end(j). We will present linear time optimal scheduling algorithms for both buffered and unbuffered WDM switches. We will also give performance studies of these switches when scheduled by these algorithms.
16465387
Rapid modeling of animated faces from video
Generating realistic 3D human face models and facial animations has been a persistent challenge in computer graphics. We have developed a system that constructs textured 3Dface models from videos with minimal user interaction. Our system takes images andvideo sequences of a face with an ordinary video camera. After five manual clicks ontwo images to tell the system where the eye corners, nose top and mouth corners are, thesystem automatically generates a realistic looking 3D human head model and the constructed model can be animated immediately. A user with a PC and an ordinary camera can use our system to generate his/her face model in a few minutes. Copyright © 2001 John Wiley & Sons, Ltd.
10630576
On cloud-antichains and related configurations
Abstract We introduce the concept of a cloud-antichain, which is a natural generalization of antichains in partially ordered sets, and solve some seemingly basic extrenal problems for them. Following the discovery of our identity (in[1]) we found the ‘missing term’, which converts Bollobas' inequality into an identity. It immediately yields the uniqueness in the Sperner Theorem for unrelated chains of subsets, which are an example of a cloud-antichain.
16878671
Full-sharing: efficient bandwidth scheduling for video streaming over broadband cable networks (BCNs)
Broadband Cable Networks (BCNs) bring high-speed Internet access to home and make emerging multimedia streaming applications feasible. However, bandwidth contention is still a challenging problem in providing efficient IP-based Video-On-Demand (VOD) service on BCNs, due to the lack of effective approaches to exploit the unique characteristics of BCNs. To address the bandwidth contention issue, we propose an efficient video scheduling technique, called full-sharing scheduling in this paper. This technique fully exploits the unique characteristics of BCNs to reduce the bandwidth consumption of video sessions sharing a cable channel of fixed capacity, thereby maximizing the number of simultaneous video sessions on the single channel. Furthermore, we analyze the expected bandwidth and the session blocking probability of a video under the full-sharing scheduling. Based on this analysis, we design an efficient video assignment mechanism for maximizing the profit of a VOD system in scheduling videos on BCNs. Through both analysis and simulation, we show that our approach minimizes the bandwidth consumption of video sessions compared with the previous approaches and has significant advantages on BCNs. The proposed approach is also directly applicable on other broadcast/multicast networks in which clients have sufficient buffer and downstream bandwidth, e.g., satellite broadband networks.