This paper proposes a programminglanguage called "Espace" for parallel and distributed computation. In general, it is difficult to code a distributed, parallel program due to multi threading, message passin...
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The model driven development (MDD) approach proposes models playing the main role on system development. However, there is not a consensual notation to model persistence based upon object relational mapping frameworks...
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ISBN:
(纸本)1891706241
The model driven development (MDD) approach proposes models playing the main role on system development. However, there is not a consensual notation to model persistence based upon object relational mapping frameworks: while UML lacks specific resources for persistence modeling, the entity-relationship model does not make reference to the dynamic concepts existing in UML. This paper proposes MD-JPA, a UML profile for persistence modeling based on the well-known java Persistence API (JPA), pursuing the modeling of transient and persistent elements in a more coherent and integrated way. This paper specifies the main characteristics of MD-JPA as well as the way that models that adopt such profile can be then turned into java implementation by the use of model transformations proposed on a MDD approach.
This paper describes a project to investigate the feasibility of building agent-based social simulation models from a combination of textual data and limited observational notes. As an example, we have developed a pro...
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ISBN:
(纸本)9780975840078
This paper describes a project to investigate the feasibility of building agent-based social simulation models from a combination of textual data and limited observational notes. As an example, we have developed a proof-of-concept java-based simulation of one notional day at a scientific conference, based on the MODSIM 2005 International Congress on Modelling and Simulation. Textual processing of the conference proceedings was used to build a common-interest network between authors, which in turn was used to drive agent processes for choosing paper presentations to attend and people with which to interact. Specifically, correlations between frequencies of word pairs was used to derive similarities between papers, and hence between authors. Diary notes taken during the MODSIM 2005 International Congress were also used in developing the simulation, which was written in the java programming language. The conference simulation shows realistic emergent phenomena, such as increasing clustering of conversing participants during the course of the day. The use of textual data does not completely eliminate the need for observational data, and more extensive observational notes would have assisted in producing a more detailed simulation of MODSIM 2005. However, we have demonstrated that the analysis of textual data can be used to simplify model development. In developing more general organisational simulations, time lags in the production of streams of text documents can be used to estimate the delays inherent in organisational processes. As a preliminary investigation of this approach, which we intend to pursue in further work, we show how a time delay can be extracted from the simple text snippets contained in two Internet news feeds. (Figure Presented).
The model checking tools Uppaal and VerICS accept a description of a network of Timed Automata with Discrete Data (TADDs) as input. Thus, to verify a concurrent program written in java by means of these tools, first a...
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The model checking tools Uppaal and VerICS accept a description of a network of Timed Automata with Discrete Data (TADDs) as input. Thus, to verify a concurrent program written in java by means of these tools, first a TADD model of the program must be build. Therefore, we have developed the J2TADD tool that translates a java program to a network of TADDs;the paper presents this tool. The J2TADD tool works in two stages. The first one consists in translation of a java code to an internal assembly language (IAL). Then, the resulting assembly code is translated to a network of TADDs. We exemplify the use of the translator by means of the following well-known concurrency examples written in java: race condition problem, dining philosophers problem, single sleeping barber problem and readers and writers problem.
There are some existing java benchmarks, application benchmarks as well as micro benchmarks or mixture both of them, such as: java Grande, Spec98, CaffeMark, HBech, etc. But none of them deal with behaviors of multi t...
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We have developed a new system using Google Earth as a data browser to visualize navigation data obtained by JAMSTEC research vessels. An XML-based language called Keyhole Markup language (KML) is used to plot data on...
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We have developed a new system using Google Earth as a data browser to visualize navigation data obtained by JAMSTEC research vessels. An XML-based language called Keyhole Markup language (KML) is used to plot data on Google Earth. We developed a program, called a KML generator, to convert navigation data to KML. The generator enables us to quickly visualize on Google Earth the cruise track of any JAMSTEC vessel. The visualized image is a powerful tool for managing information on research cruises of various JAMSTEC vessels.
Scratch [4] is both a social computing environment and a rich programminglanguage with a highly supportive interface. Although originally intended for an audience younger than college freshman, there is growing inter...
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Scratch [4] is both a social computing environment and a rich programminglanguage with a highly supportive interface. Although originally intended for an audience younger than college freshman, there is growing interest in using Scratch at the undergraduate level as a gentle introduction to hard concepts. David Malan and Henry Leitner first presented their experience teaching Harvard introductory CS courses with Scratch at SIGCSE two years ago [3]. At SIGCSE 08 John Maloney and Ursula Wolz provided the SIGCSE community with an overview of the language and the social computing website. John also presented research results at SIGCSE 08 on the popularity of programming among young people in a community clubhouse setting [4]. The kids preferred to program rather than play computer games. At both Harvard and The College of New Jersey (TCNJ) we have seen similar phenomena where the flexibility, simplicity and ease with which students can make their programming experience highly personal in a supportive community, actively engages them in the process of learning to program regardless of ethnicity or gender. The very successful Scratch@MIT conference in July 2008 brought together educators from around the world who realizethat Scratch appears to be an intriguing gateway into the discipline of programming. The social computing website supports over 100,000 registered members, who have posted approximately 200,000 projects that include approximately 5 million scripts (programs). The archive of programs includes very sophisticated computer code written by talented, well-trained and creative programmers. Yet the language is, by design, extremely simple. It is not, and never was intended to be a kitchen sink kind of language. However, a growing community continues to produce an unanticipated range of examples of how computer code, creatively developed, can produce wonderful games, stories, art, science simulations and mathematical models. Consideration for the potential of Scra
The PSP-Expert Visualization Agent (EVA) is designed for software engineers specifically to introduce the agent-oriented concept, as well as to automate all the processes and fields involved in PSP. Currently, some de...
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ISBN:
(纸本)9781424445219
The PSP-Expert Visualization Agent (EVA) is designed for software engineers specifically to introduce the agent-oriented concept, as well as to automate all the processes and fields involved in PSP. Currently, some developers of PSP automated tools include the agent's element in their system that focuses on sensor-based tracking of lines of code. However, none of them fully utilize this element for other purposes or provide the agent with a personal assistant for the software engineer. This sensor-based tracking is limited to Eclipse environments such as java and is not compatible with the use of web platforms as a PSP automated tool. The PSP-EVA system is required to perform several tasks. There are three agents that exist within the system: Interface Agent (IA), TaskAgent (TA), and SearchAgent (SA). By incorporating the multi-software agent in this automation system, PSP-EVA is able to have ready-access to applications and also to provide a visual representation of performance to the user. Additionally, evaluation of software engineers and team performance can be easily derived and evaluated statistically.
Research on wireless sensor networks (WSNs) has recently moved from the design and evaluation of protocol stacks to real-life implementation and test of the proposed solutions. It would be desirable to be able to run ...
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ISBN:
(纸本)9781424425167
Research on wireless sensor networks (WSNs) has recently moved from the design and evaluation of protocol stacks to real-life implementation and test of the proposed solutions. It would be desirable to be able to run the implementation of a given protocol stack (or of multiple stacks) over different real-life test-beds obtaining comparable results. This requires standardized interfaces to remotely access and control a federation of test-beds, tools to gather data on the protocol performance without affecting the network operations, as well as ways to standardize how data needed to compute the metrics of interest are gathered and analyzed. This paper describes the design and use of JAMES, a new Test-bed Management System for WSNs that addresses all these challenges. We also discuss the use of JAMES features to ease the experimental evaluation of protocol stacks we have developed. Our experiments show that only a few tens of lines need to be written to be able to execute tests on a given protocol stack and that JAMES operations are transparent to the stack behavior.
Although distributed object systems, including RMI and CORBA, enable object-oriented programs to be easily distributed across a network, achieving acceptable performance usually requires client-specific optimization o...
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ISBN:
(纸本)9781424444816
Although distributed object systems, including RMI and CORBA, enable object-oriented programs to be easily distributed across a network, achieving acceptable performance usually requires client-specific optimization of server interfaces, making such systems difficult to maintain and evolve. Automatic optimization techniques, including Batched Futures and Communication Restructuring, do not work as well as hand optimization. This paper presents Batched Remote Method Invocation (BRMI), a language-level technique for clients to specify explicit batches of operations on remote objects. We have implemented BRMI for java as an extension of RMI, with support for batches with array cursors, custom exception handling, conditionals and loops. BRMI allows common design patterns, including Data Transfer Objects and Remote Object Facade, to be constructed on the fly by clients. The performance benefits of batching operations are well known;our evaluation focuses on the usability of explicit batches, but we also confirm that BRMI outpeiforms RMI and scales significantly better when clients make multiple remote calls. The applicability of BRMI is demonstrated by rewriting third-party RMI client applications to use BRMI.
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