9710130
A specification language for real-time distributed systems
The authors introduce a design specification method, extended modified Petri nets (EMPN), and its description language (EMPNDL). The specification is based on a stochastic Petri-net model and is suitable for modeling real-time distributed systems. The syntax of the language is formally described in BNF grammar while the semantics is based on that for stochastic Petric nets. In addition to the modeling capability of EMPN and EMPNDL, methods for verification and validation of such systems are also discussed. EMPN and EMPNDL have been extensively used to the specification of a prototype switching system, UICPBX. Based on the presented formulation, verification and validation of UICPBX can be automated to a great extent.<<ETX>>
44831800
Formal Collaborative Production Environment
45899286
Computer Supported Cooperative Work Oriented Architecture
2457108
An object-oriented real-time distributed simulation of cellular phone switching system
The cellular phone network is a distributed system which is composed of three kinds of subsystems, a mobile phone unit, a base site station and a MSC (mobile switching center). A class of cellular phone switching systems, was chosen as the system to be studied. SUN workstations and the UNIX operating system with X windows have been employed as the core of the development environment. The object-oriented (OO) paradigm and C++ were chosen to develop the simulation. UICCELL was developed as an object-oriented system for cellular phone switching real-time multitasking simulation. UICCELL has been fully implemented and is currently running on an Ethernet LAN. A central monitor is created on the screen to manipulate and monitor the simulator. The graphical user interface displays the configuration of UICCELL and the status of processors, channels, etc. The current implementation contains 60 classes and about 20,000 lines of C++ code.<<ETX>>
11560314
Distributed systems design using function-class decomposition with aspects
Object-oriented methods are known for their capabilities to encapsulate and manage core concerns of complex software systems. However, they are inadequate in discerning and separating a variety of other cross-cutting concerns. In particular, for distributed systems, a number of important concerns such as synchronization, logging, and security, should be sufficiently treated in the design phase of the software lifecycle in order to ensure high system quality. Often these concerns tend to be overlooked at the design level and consequently scattered across multiple system modules during implementation. Consequently it becomes difficult to connect the set of requirements with the system structure, thus system traceability is reduced. This paper proposes an extension to the function-class decomposition (FCD) method, that is a hybrid method of structured analysis and OO approach, by integrating the concepts of "aspect". "Aspect" is an abstraction mechanism that emerged in recent years from the aspect-oriented programming (AOP) community. This extended method supports separation of functional and non-functional concerns by maintaining two primary views (function-class view and aspect view) at the design stage, and demonstrates the iterative process by applying it to the development of an example system called M-Net that is an Internet-based real-time distributed conferencing system.
39549662
Categorical Data Visualization and Clustering Using Subjective Factors
Clustering is an important data mining problem. However, most earlier work on clustering focused on numeric attributes which have a natural ordering to their attribute values. Recently, clustering data with categorical attributes, whose attribute values do not have a natural ordering, has received more attention. A common issue in cluster analysis is that there is no single correct answer to the number of clusters, since cluster analysis involves human subjective judgement. Interactive visualization is one of the methods where users can decide a proper clustering parameters. In this paper, a new clustering approach called CDCS (Categorical Data Clustering with Subjective factors) is introduced, where a visualization tool for clustered categorical data is developed such that the result of adjusting parameters is instantly reflected. The experiment shows that CDCS generates high quality clusters compared to other typical algorithms.
10317156
A research on Collaboration Net
We present research on computer-supported cooperative work by introducing an approach to the multimedia based net-centric conference environment-Collaboration Net. Some basic definitions of the distributed Web-based meeting are provided, and the properties of this kind of collaboration are given. We explain problems associated with the well-known yet old-fashioned parliamentary procedure, Robert's Rules of Order, which must be formally modeled and adapted to the modern net-centric virtual conference where time synchronism is hard to enforce. A prototype of our Web-browser based approach to developing the Collaboration Net is also briefly presented. Finally, research challenges in this area are highlighted.
32612296
Automating performance-related impact analysis through event based traceability
Current impact analysis techniques tend to focus on assessing the impact of change upon the system's functionality, whilst a consideration of performance related requirements is often deferred until after implementation. This tendency can lead to costly and time-consuming mistakes that frustrate customers and require frantic last-minute efforts to fix. This paper proposes a method for supporting performance-related impact analysis in a heterogeneous software engineering environment. An event-based approach is taken to establish dynamic traceability links, capable of propagating data values and commands between requirements and performance models. Quantitative values in performance related requirements are adjusted to reflect proposed changes, and impacted models are re-executed to measure the impact of the change. The resulting outputs are then automatically compared to relevant performance requirements and a system-wide report showing the impact of the proposed change upon performance is generated.
11608556
MORF: A Distributed Multimodal Information Filtering System
The proliferation of objectionable information on the Internet has reached a level of serious concern. To empower end-users with the choice of blocking undesirable and offensive Web-sites, we propose a multimodal personalized information filter, named MORF. The design of MORF aims to meet three major performance goals: efficiency, accuracy, and personalization. To achieve these design goals, we have devised a multimodality classification algorithm and a personalization algorithm. Empirical study and initial statistics collected from the MORF filters deployed at sites in the U.S. and Asia show that MORF is both efficient and effective, compared to the traditional URL- and text-based filtering approaches.