MUPPET: A programming environment for message-based multiprocessors

MUPPET is a problem-solving environment for scientific computing with message-based multiprocessors. It consists of four part—concurrent languages, programming environments, application environments and man-machine interfaces. The programming paradigm of MUPPET is based on parallel abstract machines and transformations between them. This paradigm allows the development of programs which are portable among multiprocessors with different interconnection topologies.

In this paper we discuss the MUPPET programming paradigm. We give an introduction to the language CONCURRENT MODULA-2 and the graphic specification system GONZO. The graphic specification system tries to introduce graphics as a tool for programming. It is also the basis for programming generation and transformation.     

Primitives for distributed computing in a heterogeneous local areanetwork environment

Epsilon is a testbed for monitoring distributed applications involving heterogeneous computers, including microcomputers, interconnected by a local area network. Such a hardware configuration is usual but raises difficulties for the programmer. First, the interprocess communication mechanisms provided by the operating systems are rather cumbersome to use. Second, they are different from one system to another. Third, the programmer of distributed applications should not worry about system and/or network aspects that are not relevant for the application level. The authors present the solution chosen in Epsilon. A set of high-level communication primitives has been designed and implemented to provide the programmer with an interface independent of the operating system and of the underlying interprocess communications facilities. A program participating in a distributed application can be executed on any host without any change in the source code except for host names     

A comprehensive agent-based architecture for intelligent information retrieval in a distributed heterogeneous environment

The Internet has become the global infrastructure supporting information acquisition and retrieval from many heterogeneous data sources containing high-speed text and rich multimedia images, audio, and video. AgentRAIDER is an ongoing research project at Texas Tech University designed to develop a comprehensive architecture for an intelligent information retrieval system with distributed heterogeneous data sources. The system is designed to support intelligent retrieval and integration of information from the Internet. Current systems of this nature focus only on specific aspects of the distributed heterogeneous problem such as database queries or information filtering. Consequently, these concepts and others have never been successfully integrated into a unified, cohesive architecture. This paper discusses the design and implementation of the AgentRAIDER system and identifies areas for applications of the system in various domains.     

Framework for distributed video surveillance in heterogeneous environment

In order to overcome the disadvantages of traditional centralized video monitoring system or distributed systems based on wired network, we propose a framework for distributed video surveillance in heterogeneous environment. Video flows are compressed with the scalable video encoding standard MPEG-4 and transmitted over lnternet or wireless network. Video surveillance can be performed wherever there is Internet or mobile telephone signal. The feasibility of this framework has been demonstrated with a prototype implementation. The system is cheaper and easier to achieve with simple equipments, so it can be widely used in practice.     

分布异构环境下数据库访问技术的研究

详细分析了当前分布异构数据库访问技术的研究现状和发展趋势,结合Web Services的优势构造了一个基于Web Services的分布异构数据库访问系统,并阐述了系统的实现过程。该系统能够有效地支持分布式数据查询,数据源透明并且支持跨平台检索。     

A solution of multidisciplinary collaborative simulation for complex engineering systems in a distributed heterogeneous environment

This paper presents an integrated approach to multidisciplinary collaborative simulation for complex engineering systems. The formulized paradigm of multidisciplinary collaborative simulation for com- plex engineering systems is principally analyzed. An IEEE HLA and web services based framework is proposed to provide a heterogeneous, distributed and collaborative running environment where multidisciplinary modeling, running management and post-processing of collaborative simulation are undertaken. The mecha...     

An efficient list-based task scheduling algorithm for heterogeneous distributed computing environment

The task scheduling in heterogeneous distributed computing systems plays a crucial role in reducing the makespan and maximizing resource utilization. The diverse nature of the devices in heterogeneous distributed computing systems intensifies the complexity of scheduling the tasks. To overcome this problem, a new list-based static task scheduling algorithm namely Deadline-Aware-Longest-Path-of-all-Predecessors (DA-LPP) is being proposed in this article. In the prioritization phase of the DA-LPP algorithm, the path length of the current task from all its predecessors at each level is computed and among them, the longest path length value is assigned as the rank of the task. This strategy emphasizes the tasks in the critical path. This well-optimized prioritization phase leads to an observable minimization in the makespan of the applications. In the processor selection phase, the DA-LPP algorithm implements the improved insertion-based policy which effectively utilizes the unoccupied leftover free time slots of the processors which improve resource utilization, further least computation cost allocation approach is followed to minimize the overall computation cost of the processors and parental prioritization policy is incorporated to further reduce the scheduling length. To demonstrate the robustness of the proposed algorithm, a synthetic graph generator is used in this experiment to generate a huge variety of graphs. Apart from the synthetic graphs, real-world application graphs like Montage, LIGO, Cybershake, and Epigenomic are also considered to grade the performance of the DA-LPP algorithm. Experimental results of the DA-LPP algorithm show improvement in performance in terms of scheduling length ratio, makespan reduction rate , and resource reduction rate when compared with other algorithms like DQWS, DUCO, DCO and EPRD. The results reveal that for 1000 task set with deadline equals to two times of the critical path, the scheduling length ratio of the DA-LPP algorithm is better than DQWS by 35%, DUCO by 23%, DCO by 26 %, and EPRD by 17%.     

A remote computation facility for a heterogeneous environment

The authors describe THERE (the heterogeneous environment for remote execution), a general-purpose facility designed to simplify the adaptation of nonnetworked, nonheterogeneous applications to a distributed heterogeneous environment. Existing applications made accessible with THERE become heterogeneous network services, and users of those services become heterogeneous network clients. They discuss the problems of remote computation, provide an overview of THERE, and describe the building of THERE applications. They present TPL, THERE programming language, which is tailored toward building execution environments for application programs (on the server sided), defining client interfaces to remote services (on the client side), and providing system-independent communication between client and server interfaces     

Alphorn: a remote procedure call environment for fault-tolerant,heterogeneous, distributed systems

Alphorn, a software environment for programming distributed computer systems, is described. Programs running on different computers, possibly of different types and running different operating systems, communicate in a client-server relationship by means of remote procedure calls. This efficient construct structures programs neatly. The paper covers distributed process control, Alphorn's object-based programming style, remote procedure calls, the service interface language, configuration, runtime and debugging, and fault tolerance support     

A predictable real-time kernel for distributed multisensor systems

The authors present a real-time kernel developed to support a distributed multisensor system encountered in robotics applications. To ensure predictability, the kernel provides services with bounded worst-case execution times. In addition, the kernel allows the programmer to specify timing constraints for process execution and interprocess communication. The kernel uses these timing constraints both for scheduling processes and for scheduling communications. To illustrate the kernel, the authors describe a multisensor system being developed on their distributed real-time system. They present the measured performance of kernel primitives along with conclusions and remarks regarding distributed real-time systems     

Distributed object management integrating distributed information in heterogeneous environment

Organizations today need an optimized environment that builds and integrates diverse operating systems, hardware and applications. Distributed Computing provides us with a facility to transparently access all data, resources in the network. Current Research, projects that distributed object management concept along with the distributed computing environment can provide a single interface to manage the complexities of a heterogeneous environment. Using a uniform framework based on the DCE standard, we attempt to create an Object Oriented Distributed Computing Environment that will help us create open distributed applications with location independence for client applications in a multivendor network.

A better model for Open Distributed Computing aided by Object Oriented concepts is offered. Some of the research issues in realizing such a model are contemplated. We integrate an Object Manager with the OSF' DCE and discuss its benefits.     

A query processing algorithm for a system of heterogeneous distributed databases

This paper presents a query processing algorithm, formulated and developed in support of the prototype architecture of the Distributed Access View Integrated Database (DAVID) which is a heterogeneous distributed database management system. The objective of the proposed query processing algorithm is to produce an inexpensive strategy for a given query. The inexpensive query strategy is obtained primarily by computing the most profitable semi-joins and by determining the best sequence of join operations per processing site. The latter is obtained by applying a zero-one integer linear program that uses a non-parametric statistical estimation technique to compute the sizes of the temporary clusters. A cluster is a subset of the cartesian product of a list of atomic and non-atomic domains and is the structure that can represent in a uniform way data stored in relational, hierarchical and network databases.Following some background information on the development of the DAVID prototype, this paper introduces the schema architecture. The schema architecture describes the mechanism by which the component heterogeneous database schemata are mapped into the uniform global schema. This is followed by the formulation of the query processing algorithm, its implementation and an illustration of its use in the context of NASA's Astrophysics Data System.Recommended by: Y. Breitbart     

异构分布环境下数据获取与多态发布

随着生产全球化和协作化的发展,企业生产与外界的交互和相互依赖日益密切,出现了如何按照数据消费者的需求将企业内部多样分布的数据友好地向外发布的问题。为了解决这一问题,提出了一种基于XML和J2EE的数据获取与发布技术,并以一个报表生成系统的设计为例阐明这一技术。利用XML可以方便、准确地描述企业的数据并且可以灵活地将数据发布到Web上,而J2EE可以将异构分布的企业信息系统与Web集成起来。     

A message-based cocktail watermarking system

A noise-type Gaussian sequence is most commonly used as a watermark to claim ownership of media data. However, only a 1-bit information payload is carried in this type of watermark. For a logo-type watermark, the situation is better because it is visually recognizable and more information can be carried. However, since the sizes and shapes of logos for different organizations are different, the flexibility of use of a logo-type watermark will certainly be degraded. In this paper, a more flexible type of watermark, i.e., a message, is designed. Since a message is composed of a finite number of ASCII-type characters, it is by nature vulnerable to attacks. Therefore, we propose to choose a set of nonlinear Hadamard-codes that has the maximum Hamming distance between any two constituent codes to replace the original ASCII-type inputs. This design will make our system much more fault-tolerant in comparison with ASCII-code based systems under direct attack. To recover an attacked Hadamard code, we use a trained backpropagation neural network to perform inexact matching. The proposed Hadamard code-based message is embedded using the cocktail-watermarking scheme (IEEE Trans. Multimedia 2 (4) (2000) 209-224) for copyright protection. Experimental results demonstrate that our message-based cocktail watermarking system is superb in terms of robustness and flexibility.     

A multilevel distributed image based encryption for full integrity

Multimedia Tools and Applications - Sending and receiving information in today’s world has become easy. Recent advancements in the technology have made the world shrink. The transfer of data...     

: A heterogeneous environment for HPC applications

Technological directions for innovative HPC software environments are discussed in this paper. We focus on industrial user requirements of heterogeneous multidisciplinary applications, performance portability, rapid prototyping and software reuse, integration and interoperability of standard tools. The various issues are demonstrated with reference to the PQE2000project and its programming environment Skeleton-based Integrated Environment ( ). includes a coordination language, , allowing the designers to express, in a primitive and structured way, efficient combinations of data parallelism and task parallelism. The goal is achieving fast development and good efficiency for applications in different areas. Modules developed with standard languages and tools are encapsulated into structures to form the global application. Performance models associated to the coordination language allow powerful optimizations to be introduced both at run time and at compile time without the direct intervention of the programmer. The paper also discusses the features of the environment related to debugging, performance analysis tools, visualization and graphical user interface. A discussion of the results achieved in some applications developed using the environment concludes the paper.     

A distributed heterogeneous supercomputing management system

A general management framework for distributed heterogenous supercomputing systems (DHSSs) that is based on an application-characterization technique is presented. The technique uses code profiling and analytical benchmarking of supercomputers. An optimal scheduling of tasks in these systems is an NP-complete problem. The use of network caching to reduce the complexity associated with the scheduling decisions is discussed. An experimental prototype of a DHSS management system is described     

A distributed development environment for embedded software

The HAGAR project is building a high-performance disk controller. It is an embedded system for which many hundreds of thousands of lines of embedded software will have to be developed concurrently with the development of the hardware. We found existing methods for embedded software development, such as simulation and remote cross development, to be inadequate for us. To meet our special needs, we developed a distributed development environment that combines and extends the capabilities of existing methods while fixing their drawbacks. Our environment is based on a processor-pool architecture, in which multiple hardware sets are pooled and managed systematically. It supports embedded software development for many programmers at different sites. It allows for the emulation of non-existing hardware adaptor cards and for the integration of embedded software testing with hardware simulation. The environment provides a single system image, hiding many hardware and configuration details from its users. From the perspective of the programmers, our environment makes developing embedded software for special hardware systems as easy as developing application programs for a UNIX workstation.