6058975
GridFlow: workflow management for grid computing
Grid computing is becoming a mainstream technology for large-scale distributed resource sharing and system integration. Workflow management is emerging as one of the most important grid services. In this work, a workflow management system for grid computing, called GridFlow, is presented, including a user portal and services of both global grid workflow management and local grid sub-workflow scheduling. Simulation, execution and monitoring functionalities are provided at the global grid level, which work on top of an existing agent-based grid resource management system. At each local grid, sub-workflow scheduling and conflict management are processed on top of an existing performance prediction based task scheduling system. A fuzzy timing technique is applied to address new challenges of workflow management in a cross-domain and highly dynamic grid environment. A case study is given and corresponding results indicate that local and global grid workflow management can coordinate with each other to optimise workflow execution time and solve conflicts of interest.
5352336
Queue scheduling and advance reservations with COSY
Summary form only given. Most of current job scheduling systems for supercomputers and clusters provide batch queuing support. With the development of metacomputing and grid computing, users require resources managed by multiple local job schedulers. Advance reservations are becoming essential for job scheduling systems to be utilized within a large-scale computing environment with geographically distributed resources. COSY is a lightweight implementation of such a local job scheduler with support for both queue scheduling and advance reservations. COSY queue scheduling utilizes the FCFS algorithm with backfilling mechanisms and priority management. Advance reservations with COSY can provide effective QoS support for exact start time and latest completion time. Scheduling polices are defined to reject reservations with too short notice time so that there is no start time advantage to making a reservation over submitting to a queue. Further experimental results show that as a larger percentage of reservation requests are involved, a longer mandatory shortest notice time for advance reservations must be applied in order not to sacrifice queue scheduling efficiency.
20842555
Agent-Based Resource Management for Grid Computing
It is envisaged that the grid infrastructure will be a large-scale distributed software system that will provide high-end computational and storage capabilities to differentiated users. A number of distributed computing technologies are being applied to grid development work, including CORBA and Jini. In this work, we introduce an A4 (Agile Architecture and Autonomous Agents) methodology, which can be used for resource management for grid computing. An initial system implementation utilises the performance prediction techniques of the PACE toolkit to provide quantitative data regarding the performance of complex applications running on local grid resources. At the meta-level, a hierarchy of identical agents is used to provide an abstraction of the system architecture. Each agent is able to cooperate with other agents to provide service advertisement and discovery to schedule applications that need to utilise grid resources. A performance monitor and advisor (PMA) is in development to optimize the performance of agent behaviours.
11437862
Implementation of Grid-Enabled Medical Simulation Applications Using Workflow Techniques
GEMSS is a European project that aims at providing high performance medical simulation services in a distributed and grid computing environment. The GEMSS grid middleware is designed using web services technologies and standards and provides support for authorization, workflow, security, Quality of Service aspects. In this work, one of the GEMSS applications, maxillo-facial surgery simulation, is described, which includes a complete chain of tools necessary for the entire process from geometric model generation from scan data to computer simulation and visualization. The Triana workflow environment is utilized to implement the application for uniform access of local processes (e.g. image pre-processing and meshing), interactive tools (e.g. mesh manipulation) and grid-enabled remote services (e.g. HPC finite element simulation). It is concluded that workflow provides benefits to flexibility, reusability and scalability and is potential to become a mainstream grid application enabling technology.
13063177
Self-organizing agents for grid load balancing
A computational grid is a wide-area computing environment for cross-domain resource sharing and service integration. Resource management and load balancing are key concerns when implementing grid middleware and improving resource utilization. Grid resource management can be implemented as a multiagent system with resource advertisement and discovery capabilities if job requests from users are associated with explicit QoS requirements. In this work agent-based self-organization is proposed to perform complementary load balancing for batch jobs with no explicit execution deadlines. In particular, an ant-like self-organizing mechanism is introduced and proved to be powerful to achieve overall grid load balancing through a collection of very simple local interactions. A modeling and simulation environment is developed to enable performance of the ant algorithm to be investigated quantitatively. Simulation results included in this work illustrate the impact of different performance optimization strategies on the overall system load balancing level, speed and efficiency.
6358095
Performance prediction technology for agent-based resource management in grid environments
This paper introduces a resource management infrastructure for grid computing environments. The technique couples application performance prediction with a hierarchical multi-agent system. An initial system implementation utilises the performance prediction capabilities of the PACE toolkit to provide quantitative data regarding the performance of complex applications running on local grid resources. The validation results show that a high level of accuracy can be obtained, that cross-platform comparisons can be easily undertaken, and that the estimates can be evaluated rapidly. A hierarchy of homogeneous agents are used to provide a scalable and adaptable abstraction of the grid system architecture. An agent is a representative of a local grid resource and is considered to be both a service provider and a service requestor. Agents are organised into a hierarchy and cooperate to provide service advertisement and discovery. A performance monitor and advisor has been developed to optimise the performance of the agent system. A case study with corresponding experimental results are included to demonstrate the efficiency of the resource management and scheduling system.
17862666
Virtual Interaction for Effective E-Learning
This research investigates whether information technologies, such as automated question answering (QA), can add interactivity into a multimedia-based e-learning system, as well as how this type of virtual interaction affects the effectiveness of e-learning. Based on a review of multiple learning theories and technologies, an exploratory model for studying the effectiveness of interactive e-learning, Learning with Virtual Mentors (LVM), is proposed and a prototype system is developed to implement the LVM model. A series of studies, including a controlled experiment and surveys, have been conducted to explore the relationships among the core constructs of the LVM model: learning phases, system interactivity, learning activity, and learning outcomes. Findings indicate that virtual interaction positively impacts student behaviors by encouraging students to interact more and increasing student satisfaction with the learning process; however, the correlation between virtual interaction and actual learning performance is limited. Consequently, the LVM model needs to be further explored and developed.
986758
The Interaction of Research Methods for System Evaluation and Theory Testing: A New Vision of the Benefits of Multi-Methodological Information Systems Research
A number of multi-methodological Information Systems research frameworks have been proposed to guide research in the IS field. In this paper, we describe a three-year program of research evaluating a computerbased training system for deception detection (Agent99 Trainer) using one such multi-methodological IS framework. The process and results of this research program clearly demonstrate the benefits of combining and triangulating multiple research methods. Moreover, through the experiences in the Agent99 Trainer study, we discover two different types of interactions between the research methods that were applied in this study. One of the interactions is between the results from different methods, while the other is between the results and the methods themselves. Hence, we propose an extended interpretation of multi-methodological IS research frameworks to incorporate these two types of interactions between research methods. We argue that this extended interpretation will provide a more specific explanation for why the triangulation among multiple research methods can provide benefits to IS research.