10015971
Predicting Change Impact in Architecture Design with Bayesian Belief Networks
Research into design rationale in the past has focused on the representation of reasons and has omitted the connections between design rationales and design artefacts. Without such connections, designers and architects cannot easily assess how changing requirements or designs may affect the system. In this paper, we introduce a model called Architecture Rationale and Element Linkage (AREL) to represent the causal relationship between architecture elements and decisions. We further model AREL as a Bayesian Belief Network (BBN) to capture the probabilistic relationships between architecture elements and decisions in an architecture design model. Such probabilistic modelling enables architects to quantitatively predict and diagnose impact of change when part of the requirements or designs are changing. Using a partial design of a cheque image processing system, we illustrate how AREL is used to represent the decision model and how BBN is used to predict and diagnose change in the architecture design. We use a UML tool to capture the AREL model and a BBN tool to compute the probabilities of change impact.
10149363
A comparative analysis of architecture frameworks
Architecture frameworks are methods used in architecture modeling. They provide a structured and systematic approach to designing systems. To date there has been little analysis on their roles in system and software engineering and if they are satisfactory. This study provides a model of understanding through analyzing the goals, inputs and outcomes of six architecture frameworks. It characterizes two classes of architecture frameworks and identifies some of their deficiencies. To overcome these deficiencies, we propose to use costs, benefits and risks for architecture analysis. We also propose a method to delineate architecture activities from detailed design activities.
17910560
Providing configuration management support in software engineering environments
Software configuration management (CM) is a key element of any software development project. A software engineering environment should not only provide support for software products and software processes in general, but also pay attention to high-level software engineering concepts like CM. In this paper, we present an overview of our approach to software engineering environments and demonstrate how CM can be achieved in such environments with minimal effort by codifying a CM model. Issues addressed include the structures and consistency of CM components and their relationships, the definition and activation of CM operations, and the definition of presentation views that facilitate CM activities.
3251598
TRAM: a tool for requirements and architecture management
Management of system requirements and system architectures is part of any software engineering project. But it is usually very tedious and error prone. In particular, managing the traceability between system requirements and system architectures is critical but difficult. The article introduces a tool, TRAM, for managing system requirements, system architectures and more importantly the traceability between them. Its primary design objective is "being practical" and ready for practitioners to use without much overhead. The issues discussed in the paper include an information model that underlies the capture of requirements, architectures and their traceability, a set of document templates implementing the information model, and the support tool.
1659291
A Software Engineering Perspective for Services Security
Services are usually developed and deployed independently; and systems can be formed by composing relevant services to achieve set goals. In such an open and dynamic environment, security is of paramount importance. We have seen much work in the traditional area of information and network security, focusing on developing various security techniques. More recently, there have been efforts in integrating the security techniques into languages and infrastructural support that are used for developing services and systems. In fact, the development of services and the composition of service-based systems are software engineering activities. As such, they need to be viewed from a software engineering perspective. In this paper, we introduce an approach to services security engineering, to answer the questions like what the security properties of services and service-based systems are and how they meet the user’s security requirements. It deals with the issues of (1) security property characterisation for services, (2) compositional security analysis for service-based systems, and (3) certification of services.
629310
Semantic and Usage Packaging for Software Components
Current models for software components have made component-based software engineering practical. However, these models are limited in the sense that their support for the specification of software components primarily deals with syntactic issues. To facilitate interoperability and proper use of software components, more comprehensive specification of these components is required. In this paper, we present an approach to software component packaging aimed at comprehensive component specification, especially its support for semantic and usage specification.
15503890
Provide privacy for mobile P2P systems
Nowadays privacy and anonymity have become an increasing requirement in wireless networks. However, current mobile peer-to-peer architectures have not taken into account anonymity, especially the mutual anonymity between two nodes. In this paper, we propose a mutual anonymity protocol, called secret-sharing-based mutual anonymity protocol (SMA), for mobile P2P networks. Our simulation results show that SMA achieves mutual anonymity in mobile P2P networks with a low cryptography processing overhead.
14694684
A mutual anonymous peer-to-peer protocol design
Peer-to-peer (P2P) computing has become a popular application model because of its easy resource sharing pattern and powerful query search scheme. However, decentralized P2P architecture is scarcely seen to deploy the anonymity on its peers. In this paper, we propose a mutual anonymity protocol, called Secret-sharing-based Mutual Anonymity Protocol (SSMP), for decentralized P2P systems. SSMP employs Shamirs' secret sharing scheme to allow peers to issue queries and responders to deliver requested files anonymously. Compared with previous designs, SSMP achieves mutual anonymity in P2P systems with a high degree of anonymity and a low cryptography processing overhead. We evaluate SSMP by comprehensive simulations.
15256739
Performance prediction for individual recognition by gait
Existing gait recognition approaches do not give their theoretical or experimental performance predictions. Therefore, the discriminating power of gait as a feature for human recognition cannot be evaluated. In this paper, we first propose a kinematic-based approach to recognize human by gait. The proposed approach estimates 3D human walking parameters by performing a least squares fit of the 3D kinematic model to the 2D silhouette extracted from a monocular image sequence. Next, a Bayesian-based statistical analysis is performed to evaluate the discriminating power of extracted stationary gait features. Through probabilistic simulation, we not only predict the probability of correct recognition (PCR) with regard to different within-class feature variance, but also obtain the upper bound on PCR with regard to different human silhouette resolution. In addition, the maximum number of people in a database is obtained given the allowable error rate. This is extremely important for gait recognition in large databases.
2286606
Scene-Level Analysis for Tennis Sports Video using Weighted Linear Combination of Visual Cues
We present a scene-level analysis system that takes TV broadcasted tennis footage as input and produces a behavior analysis of the moving-players in the scene. To achieve this functionality, our algorithm relies on two modular blocks. The first one detects and tracks a number of key objects in the image domain, like moving-players and the playing-field. Afterwards, a camera-calibration algorithm is applied that uses the lines of the court as a reference and transforms image coordinates to physical positions to compute the camera parameters. The second block firstly models several important events of a tennis game, such as service and net-approach, based on four real-world visual features provided by the first block. This paper proposes a new improved model, since it weights the importance of each visual cue to different events, rather than providing a simple combination of these four visual cues as was done in previous work. Based on the new model, we can accurately determine what kind of event the current input frame belongs to. Furthermore, we detect the start time and end time of each event using a simple but efficient temporal filter. Our proposed system is capable of classifying each tennis play into three semantic categories, which are popular and familiar to most viewers. This paper presents details of the system, together with results on a number of tennis video sequences.
40646697
HAND: An Overlay Optimization Algorithm in Peer-to-Peer Systems
Recently, peer-to-peer (P2P) model becomes popular due to its outstanding resource sharing ability in large-scale distributed systems. However, the most popular P2P system – unstructured P2P system, suffers greatly from the mismatching between the logical overlay and physical topology. This mismatching problem causes a large volume of redundant traffic, which makes peer-to-peer system far from scalable and degrades their search efficiency dramatically. In this paper we address the mismatching problem in an unstructured P2P architecture by developing a distributed overlay optimizing algorithm – HAND (Hops Adaptive Neighbor Discovery). Through comprehensive simulations, we show that HAND significantly outperforms previous approaches, especially in large-scale P2P systems.