57 research outputs found
UTILIZATION OF THE LINE-INTERCEPT METHOD TO ESTIMATE THE COVERAGE, DENSITY, AND AVERAGE LENGTH OF ROW SKIPS IN COTTON AND OTHER ROW CROPS
In row crops, a skip is a length of row within the drill where the crop has failed to establish. If the number of skips and their mean length per acre becomes too high, then considerable losses in crop yield occur. Frequently, farmers are faced with the decision to replant a crop which has row skips. To make the best decision, reliable estimates of the stand loss due to skips must be available. In making this decision, three parameters are useful: the percent of the area per acre that is skipped, the number of individual skips (that is, density) per acre, and the mean row length per skip. The line-intercept method for the sampling of two-dimensional objects (particles) can be used to obtain estimates of these parameters. The method is illustrated with an example from a cotton field
Job Monitoring in an Interactive Grid Analysis Environment
The grid is emerging as a great computational resource but
its dynamic behavior makes the Grid environment unpredictable. Systems and networks can fail, and the
introduction of more users can result in resource starvation.
Once a job has been submitted for execution on the grid,
monitoring becomes essential for a user to see that the job is completed in an efficient way, and to detect any problems
that occur while the job is running. In current environments
once a user submits a job he loses direct control over the job and the system behaves like a batch system: the user
submits the job and later gets a result back. The only
information a user can obtain about a job is whether it is
scheduled, running, cancelled or finished. Today users are
becoming increasingly interested in such analysis grid
environments in which they can check the progress of the
job, obtain intermediate results, terminate the job based on
the progress of job or intermediate results, steer the job to
other nodes to achieve better performance and check the
resources consumed by the job. In order to fulfill their
requirements of interactivity a mechanism is needed that
can provide the user with real time access to information
about different attributes of a job. In this paper we present
the design of a Job Monitoring Service, a web service that
will provide interactive remote job monitoring by allowing
users to access different attributes of a job once it has been submitted to the interactive Grid Analysis Environment
Job Interactivity Using a Steering Service in an Interactive Grid Analysis Environment
Grid computing has been dominated by the execution of batch jobs. Interactive data analysis is a new domain in the area of grid job execution. The Grid-Enabled Analysis Environment (GAE) attempts to address this in HEP grids by the use of a Steering Service. This service will provide physicists with the continuous feedback of their jobs and will provide them with the ability to control and steer the execution of their submitted jobs. It will enable them to move their jobs to different grid nodes when desired. The Steering Service will also act autonomously to make steering decisions on behalf of the user, attempting to optimize the execution of the job. This service will also ensure the optimal consumption of the Grid user's resource quota. The Steering Service will provide a web service interface defined by standard WSDL. In this paper we have discussed how the Steering Service will facilitate interactive remote analysis of data generated in Interactive Grid Analysis Environment
Distributed Analysis and Load Balancing System for Grid Enabled Analysis on Hand-held devices using Multi-Agents Systems
Handheld devices, while growing rapidly, are inherently constrained and lack
the capability of executing resource hungry applications. This paper presents
the design and implementation of distributed analysis and load-balancing system
for hand-held devices using multi-agents system. This system enables low
resource mobile handheld devices to act as potential clients for Grid enabled
applications and analysis environments. We propose a system, in which mobile
agents will transport, schedule, execute and return results for heavy
computational jobs submitted by handheld devices. Moreover, in this way, our
system provides high throughput computing environment for hand-held devices.Comment: 4 pages, 3 figures. Proceedings of the 3rd International Conference
on Grid and Cooperative Computing (GCC 2004
Heterogeneous Relational Databases for a Grid-enabled Analysis Environment
Grid based systems require a database access mechanism that can provide seamless homogeneous access to the requested data through a virtual data access system, i.e. a system which can take care of tracking the data that is stored in geographically distributed heterogeneous databases. This system should provide an integrated view of the data that is stored in the different repositories by using a virtual data access mechanism, i.e. a mechanism which can hide the heterogeneity of the backend databases from the client applications. This paper focuses on accessing data stored in disparate relational databases through a web service interface, and exploits the features of a Data Warehouse and Data Marts. We present a middleware that enables applications to access data stored in geographically distributed relational databases without being aware of their physical locations and underlying schema. A web service interface is provided to enable applications to access this middleware in a language and platform independent way. A prototype implementation was created based on Clarens [4], Unity [7] and POOL [8]. This ability to access the data stored in the distributed relational databases transparently is likely to be a very powerful one for Grid users, especially the scientific community wishing to collate and analyze data distributed over the Grid
Resource Management Services for a Grid Analysis Environment
Selecting optimal resources for submitting jobs on a computational Grid or
accessing data from a data grid is one of the most important tasks of any Grid
middleware. Most modern Grid software today satisfies this responsibility and
gives a best-effort performance to solve this problem. Almost all decisions
regarding scheduling and data access are made by the software automatically,
giving users little or no control over the entire process. To solve this
problem, a more interactive set of services and middleware is desired that
provides users more information about Grid weather, and gives them more control
over the decision making process. This paper presents a set of services that
have been developed to provide more interactive resource management
capabilities within the Grid Analysis Environment (GAE) being developed
collaboratively by Caltech, NUST and several other institutes. These include a
steering service, a job monitoring service and an estimator service that have
been designed and written using a common Grid-enabled Web Services framework
named Clarens. The paper also presents a performance analysis of the developed
services to show that they have indeed resulted in a more interactive and
powerful system for user-centric Grid-enabled physics analysis.Comment: 8 pages, 7 figures. Workshop on Web and Grid Services for Scientific
Data Analysis at the Int Conf on Parallel Processing (ICPP05). Norway June
200
DIANA Scheduling Hierarchies for Optimizing Bulk Job Scheduling
The use of meta-schedulers for resource management in large-scale distributed systems often leads to a hierarchy of schedulers. In this paper, we discuss why existing meta-scheduling hierarchies are sometimes not sufficient for Grid systems due to their inability to re-organise jobs already scheduled locally. Such a job re-organisation is required to adapt to evolving loads which are common in heavily used Grid infrastructures. We propose a peer-topeer scheduling model and evaluate it using case studies and mathematical modelling. We detail the DIANA (Data Intensive and Network Aware) scheduling algorithm and its queue management system for coping with the load distribution and for supporting bulk job scheduling. We demonstrate that such a system is beneficial for dynamic, distributed and self-organizing resource management and can assist in optimizing load or job distribution in complex Grid infrastructures
Predicting the Resource Requirements of a Job Submission
Grid computing aims to provide an infrastructure for
distributed problem solving in dynamic virtual
organizations. It is gaining interest among many scientific
disciplines as well as the industrial community. However,
current grid solutions still require highly trained
programmers with expertise in networking, high-performance
computing, and operating systems. One of the big issues in full-scale usage of a grid is matching the resource requirements of job submission to the resources available on the grid. Resource brokers and job schedulers must make estimates of the resource usage of job submissions in order to ensure efficient use of grid resources. We prop ose a prediction engine that will operate as part of a grid scheduler. This prediction engine will provide estimates of the resources required by job submission based upon historical information. This paper presents the need for such a prediction engine and discusses two approaches for history based estimation
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