7156676
The design and implementation of scalable information services in a grid environment
This paper proposes an Extensible Monitoring and Discovery Service for grid environment MASSIVE (MEMDS). The MASSIVE project focuses on developing a multidisciplinary applications-oriented simulation and visualization environment. In the MEMDS, appropriate mechanisms make custom information services established and deployed easily, and the developed APIs simplify the access to the MDS and provide a uniform interface for programmers. Corresponding practices show that the MEMDS improves the extensibility and flexibility of the grid information service.
11888498
The Design and Implementation of Extensible Information Services
High-performance distributed computing often requires careful selection and configuration of computers, networks, application protocols, and algorithms. In grid environment, the participators of domains provide site information by default that may be not adequate for resources manager to achieve optimal performance. In this paper, an Extensible Information Service Architecture (EISA) is described to resolve this problem. EISA supports a virtual organization participator's autonomous control of local resources. It consists of three layers, the registration and deployment layer, normalization and organization layer, and information collection layer. Dynamic information services in EISA could be deployed and extended easily. EISA improves the extensibility of grid information services and the efficiency of resources utilization.
20644298
MASSIVE: a multidisciplinary applications-oriented simulation and visualization environment
The objective of the MASSIVE project is to build a grid platform to enable large-scale and distributed scientific and engineering computations. Its focus is numerical simulation and visualization. This paper addresses a prototype grid utilizing resources at the Center for Engineering and Scientific Computation (CESC) in Zhejiang University (ZJU). This grid is capable of taking a model geometry generated by CAD systems, transferring it to an SGI Onyx 3900 supercomputer where it is meshed. The meshed geometry is then transferred to a Dawning PC cluster where it is used to solve computational fluid dynamics and computational solid mechanics problems and it is finally visualized showing numerical results.
12596805
FMC: An Approach for Privacy Preserving OLAP
To preserve private information while providing thorough analysis is one of the significant issues in OLAP systems. One of the challenges in it is to prevent inferring the sensitive value through the more aggregated non-sensitive data. This paper presents a novel algorithm FMC to eliminate the inference problem by hiding additional data besides the sensitive information itself, and proves that this additional information is both necessary and sufficient. Thus, this approach could provide as much information as possible for users, as well as preserve the security. The strategy does not impact on the online performance of the OLAP system. Systematic analysis and experimental comparison are provided to show the effectiveness and feasibility of FMC.
13205970
Performance analysis of several algorithms for processing joins between textual attributes
Three algorithms for processing joins on attributes of a textual type are presented and analyzed in this paper. Since such joins often involve document collections of very large size, it is very important to find efficient algorithms to process them. The three algorithms differ according to whether the documents themselves or the inverted files on the documents are used to process the join. Our analysis and simulation results indicate that the relative performance of these algorithms depends on the input document collections, the system characteristics and the input query. For each algorithm, the type of input document collection with which the algorithm is likely to perform well is identified.
16609668
Throughput vs. Distance Tradeoffs and Deployment Considerations for a Multi-Hop IEEE 802.16e Railroad Test Bed
Throughput vs. distance analysis and coverage requirements are critical issues in planning wireless network deployments. With the recent availability of IEEE 802.16e and its promise of larger coverage areas for high-speed data communication, evaluating it in a real-world environment is very important to us in our ongoing study of standards based wireless technologies for the Federal Railroad Administration (FRA). In this paper, we present results obtained with our IEEE 802.16e module for NS-2, particularly throughput vs. distance performance, and its consideration for designing a real-world multi-hop IEEE 802.16e testbed. Firstly, a quantitative analysis of throughput vs. distance performance is conducted via extensive simulation, and the optimal modulation and coding scheme as well as channel bandwidth profiles are identified for specific distances. Secondly, we present a real-world multi-hop IEEE 802.16e testbed design intended for installation along BNSF Railway track in Nebraska. We apply our findings towards selecting various base station deployment locations and their appropriate communications parameters in order achieve best possible multi-hop throughput performance. We also provide a client access coverage analysis for the various locations.
1107425
Information Coverage in Randomly Deployed Wireless Sensor Networks
Coverage is an important issue in wireless sensor networks. The most commonly used coverage model in the literature defines a point to be covered if its Euclidian distance to at least one sensor is less than a fixed threshold. This is a conservative definition of coverage which implicitly assumes that each sensor makes a decision independent of other sensors in the field. Sensors can cooperate to make an accurate estimation, even if any single sensor is unable to do so. We have previously proposed a new notion of information coverage and investigated its properties. In this paper, we study sensor density requirements for complete information coverage of a field with random sensor deployment. We provide an upper bound on the probability that an arbitrary point in a randomly deployed sensor field is not information covered and find the relationship between the sensor density and the average field vacancy. Simulation results validate our theoretical analysis and show that significant savings in terms of sensor density for complete coverage can be achieved with information coverage.
19122402
Moduli selection in RNS for efficient VLSI implementation
In this paper, we carry out a study on an important issue concerning the use of residue numbers in the design of digital systems, namely, the moduli selection. Based on a new formulation of the Chinese remainder theorem and the efficient residue-to-binary (R/B) converters designed therefrom, we propose a guideline for the selection of the low-cost moduli sets for different dynamic ranges. These sets consist of the low-cost moduli of the form 2/sup n/, ( 2/sup n/-1) or (2/sup n/ + 1), which can offer simplified modulo adders and multipliers. It is shown that for medium dynamic ranges (less than 22 bits), the three-moduli set {2/sup n/,2/sup n/ + 1,2/sup n/ - 1} is the most efficient one in terms of the design of a complete RNS system. On the other hand, for large dynamic ranges (equal to or larger than 22 bits), the general-moduli set in the form (2/sup n/, 2/sup n/ + 1,2/sup n/ - 1,2/sup n/ /spl plusmn/1,...,2/sup n/, /spl plusmn/1), with a length greater than three, is the most efficient one. These results provide the possibility of a wide range of applications of the residue number system in the design of DSP, telecommunication and cryptography systems.