Pegasus is a planning framework for mapping abstract workflows for execution on the Grid. This paper presents the implementation of a web-based portal for submitting workflows to the Grid using Pegasus. The portal als...
详细信息
ISBN:
(纸本)9781581139648
Pegasus is a planning framework for mapping abstract workflows for execution on the Grid. This paper presents the implementation of a web-based portal for submitting workflows to the Grid using Pegasus. The portal also includes components for generating abstract workflows based on a metadata description of the desired data products and application-specific services. We describe our experiences in using this portal for two Grid applications. A major contribution of our work is in introducing several components that can be useful for Grid portals and hence should be included in Grid portal development toolkits. Copyright 2005 acm.
Network forensics and honeynet systems have the same features of collecting information about the computer misuses. Honeynet system can lure attackers and gain information about new types of intrusions. Network forens...
详细信息
ISBN:
(纸本)9781581139648
Network forensics and honeynet systems have the same features of collecting information about the computer misuses. Honeynet system can lure attackers and gain information about new types of intrusions. Network forensics system can analysis and reconstruct the attack behaviors. These two systems integrating together can help to build an active self-learning and response system to profile the intrusion behavior features and investigate the attack original source. In this paper, we present a design of honeynet based active network intrusion response system. The features of our system are distributed adaptive network forensics and active real time network investigation. Copyright 2005 acm.
In this paper we describe a serializer component completely realized in .NET managed code, able to run on a stripped versions of the .NET platform (e.g., COMPACT FRAMEWORK) and still generic enough to be used on .NET ...
详细信息
ISBN:
(纸本)9781581139648
In this paper we describe a serializer component completely realized in .NET managed code, able to run on a stripped versions of the .NET platform (e.g., COMPACT FRAMEWORK) and still generic enough to be used on .NET or other CLI compatible frameworks. Such a component is not normally provided with stock libraries in their compact version, since its implementation is quite tricky when relying on reduced reflection services. However, this component makes easier the development of distributed applications involving mobile devices and desktop computers or mainframes. Our implementation faced several problems ranging from lack of features in the base classes to the interframework portability problem, since the same object could have different implementation. The resulting product shows satisfactory performance figures and has a modular and flexible architecture. Copyright 2005 acm.
Large-scale supercomputing is revolutionizing the way science is conducted. A growing challenge, however, is understanding the massive quantities of data produced by largescale simulations. The data, typically time-va...
详细信息
ISBN:
(纸本)9781581139648
Large-scale supercomputing is revolutionizing the way science is conducted. A growing challenge, however, is understanding the massive quantities of data produced by largescale simulations. The data, typically time-varying, multivariate, and volumetric, can occupy from hundreds of gigabytes to several terabytes of storage space. Transferring and processing volume data of such sizes is prohibitively expensive and resource intensive. Although it may not be possible to entirely alleviate these problems, data compression should be considered as part of a viable solution, especially when the primary means of data analysis is volume rendering. In this paper we present our study of multivariate compression, which exploits correlations among related variables, for volume rendering. Two configurations for multidimensional compression based on vector quantization are examined. We emphasize quality reconstruction and interactive rendering, which leads us to a solution using graphics hardware to perform on-the-fly decompression during rendering. Copyright 2005 acm.
In recent years, the discipline of computing has matured to the point of having distinct sub elements, each of which is developing curriculum recommendations, accreditation criteria, conferences, professional societie...
详细信息
ISBN:
(纸本)1581139977
In recent years, the discipline of computing has matured to the point of having distinct sub elements, each of which is developing curriculum recommendations, accreditation criteria, conferences, professional societies and publications. In particular, five distinct curriculum projects range in status from completed some time ago (computing Curricula 2001: Computer Science (CS-2001) [4] and IS 2002 Model Curriculum and Guidelines for Undergraduate Degree Programs in Information Systems (IS-2002) [1]), through almost completed as of the writing of this special session proposal, and very likely to be published by the time of SIGCSE 2005 (computing Curricula 2004: Software Engineering [2] and computing Curricula: Computer Engineering [5]) to one that will likely be finished in late 2005 or early 2006 (computing Curricula: Information Technology). More broadly, recent work in the UK to identify the variety of computing related programs currently offered in British universities identified 2,400 distinct program names [3]! We are making an interim report on, and seeking input into, a project to keep the family of computing related disciplines together. This project is partially funded by the National Science Foundation (NSF grant 0338546, Special Project: All in the Family: A unified representation of the computing and information related disciplines), and is being run by a joint task force from several professional societies, with acm taking the lead. Very roughly, the goals of the project are to provide a synthesis of all that is computing, and various ways of organizing and visualizing that synthesis. This project began in late 2003, and got started in earnest in early 2004. We anticipate completing the work late in 2005 or early in 2006. Thus SIGCSE 2005 is the perfect time for us both to report on our work to date, and to get valuable feedback from the community.
Dominated by the behavioral science approach for a long time, information systems research increasingly acknowledges design science as a complementaiy approach. While primarily information systems instantiations, but ...
详细信息
ISBN:
(纸本)9781581139648
Dominated by the behavioral science approach for a long time, information systems research increasingly acknowledges design science as a complementaiy approach. While primarily information systems instantiations, but also constructs and models have been discussed quite comprehensively, the design of methods is addressed rarely. But methods appear to be of utmost importance particularly for organizational engineering. This paper justifies method construction as a core approach to organizational engineering. Based on a discussion of fundamental scientific positions in general and approaches to information systems research in particular, appropriate conceptualizations of 'method' and 'method construction' are presented. These conceptualizations are then discussed regarding their capability of supporting organizational engineering. Our analysis is located on a meta level: Method construction is conceptualized and integrated from a large number of references. Method instantiations or method engineering approaches however are only referenced and not described in detail. Copyright 2005 acm.
Flash memory based embedded computing systems are becoming increasingly prevalent. These systems typically have to provide an instant start-up time. However, we observe that mounting a file system for flash memory tak...
详细信息
ISBN:
(纸本)9781581139648
Flash memory based embedded computing systems are becoming increasingly prevalent. These systems typically have to provide an instant start-up time. However, we observe that mounting a file system for flash memory takes 1 to 25 seconds mainly depending on the flash capacity. Since the flash chip capacity is doubled in every year, this mounting time will soon become the most dominant reason of the delay of system start-up time. Therefore, in this paper, we present instant mounting techniques for flash file systems by storing the in-memory file system metadata to flash memory when unmounting the file system and reloading the stored metadata quickly when mounting the file system. These metadata snapshot techniques are specifically developed for NOR- and NAND-type flash memories, while at the same time, overcoming their physical constraints. The proposed techniques check the validity of the stored snapshot and use the proposed fast crash recovery techniques when the snapshot is invalid. Based on the experimental results, the proposed techniques can reduce the flash mounting time by about two orders of magnitude over the existing de facto standard flash file system. Copyright 2005 acm.
Users expect access to Web data from a wide range of devices, both wired and wireless. Many users switch back and forth between devices, including laptops and Personal Data Assistants (PDAs), and expect to be able to ...
详细信息
ISBN:
(纸本)9781581139648
Users expect access to Web data from a wide range of devices, both wired and wireless. Many users switch back and forth between devices, including laptops and Personal Data Assistants (PDAs), and expect to be able to continue working with that data. The goal of this research is to inform the design of applications that support the user by providing reasonably seamless migration of Web data among internet-compatible devices with minimal loss of effectiveness and efficiency. Earlier studies concentrated on the dynamic transformation of text content, lists, and forms embedded in web pages for access on a range of devices from desktop to handheld. This study focuses on the transformation of large tables onto small mobile devices. In this paper we report on the results of two user studies that examine effectiveness and efficiency of three basic models for the display of tables, originally intended for use on larger screen, on PDA size screens for both simple and complex tasks. Copyright 2005 acm.
People quit saying "computers don't make mistakes" after the Y2K scare that generated billions of dollars in hardware upgrades, and hence the "*** bubble". Computer arithmetic with finite-lengt...
详细信息
ISBN:
(纸本)9781581139648
People quit saying "computers don't make mistakes" after the Y2K scare that generated billions of dollars in hardware upgrades, and hence the "*** bubble". Computer arithmetic with finite-length bit-strings has its limitations and creates concerns. In computational mathematics using computers, it is a pity to abandon rigor just at the point we have reduced the problem to computer algorithms. In fact we need not do so. By using pairs of machine numbers as upper and lower bounds of unknown numbers of interest, and by rounding upper bounds up and lower bounds down, we can modify ordinary floating-point machine arithmetic to produce mathematically rigorous results. This is called "interval arithmetic with outward rounding", and it has been implemented and used for several decades. In particular it has been successfully used in non-trivial computer-aided proofs in mathematical analysis, such as the Kepler conjecture (a problem that was outstanding for more than 300 years) and many others. Practical applications also abound in chemical engineering, structural engineering, economics, aircraft control circuitry design, beam physics, global optimization, differential equations, etc. Rigor in computing depends on the integrity of order relations. Commonly used floating-point hardware can lose that integrity. A few examples are presented and it is shown how we can remedy the situation and regain rigor in computing by using outwardly rounded interval arithmetic.
暂无评论