			Home About us Contact

Operations Center (operations + center)

Distribution by Scientific Domains

Business, Economics, Finance and Accounting	40%

Selected Abstracts

Concepts for computer center power management

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 2 2010
A. DiRienzo
Abstract Electrical power usage contributes significantly to the operational costs of large computer systems. At the Hypersonic Missile Technology Research and Operations Center (HMT-ROC) our system usage patterns provide a significant opportunity to reduce operating costs since there are a small number of dedicated users. The relatively predictable nature of our usage patterns allows for the scheduling of computational resource availability. We take advantage of this predictability to shut down systems during periods of low usage to reduce power consumption. With interconnected computer cluster systems, reducing the number of online nodes is more than a simple matter of throwing the power switch on a portion of the cluster. The paper discusses these issues and an approach for power reduction strategies for a computational system with a heterogeneous system mix that includes a large (1560-node) Apple Xserve PowerPC supercluster. In practice, the average load on computer systems may be much less than the peak load although the infrastructure supporting the operation of large computer systems in a computer or data center must still be designed with the peak loads in mind. Given that a significant portion of the time, systems loads can be less than full peak, an opportunity exists for cost savings if idle systems can be dynamically throttled back, slept, or shut off entirely. The paper describes two separate strategies that meet the requirements for both power conservation and system availability at HMT-ROC. The first approach, for legacy systems, is not much more than a brute force approach to power management which we call Time-Driven System Management (TDSM). The second approach, which we call Dynamic-Loading System Management (DLSM), is applicable to more current systems with ,Wake-on-LAN' capability and takes a more granular approach to the management of system resources. The paper details the rule sets that we have developed and implemented in the two approaches to system power management and discusses some results with these approaches. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Gravisensitivity and automorphogenesis of lentil seedling roots grown on board the International Space Station

PHYSIOLOGIA PLANTARUM, Issue 1 2008
Dominique Driss-Ecole
The GRAVI-1 experiment was brought on board the International Space Station by Discovery (December 2006) and carried out in January 2007 in the European Modular Cultivation System facility. For the first run of this experiment, lentil seedlings were hydrated and grown in microgravity for 15 h and then subjected for 13 h 40 min to centrifugal accelerations ranging from 0.29 × 10,2 g to 0.99 × 10,2 g. During the second run, seedlings were grown either for 30 h 30 min in microgravity (this sample was the control) or for 21 h 30 min and then subjected to centrifugal accelerations ranging from 1.2 × 10,2 g to 2.0 × 10,2 g for 9 h. In both cases, root orientation and root curvature were followed by time-lapse photography. Still images were downlinked in near real time to ground Norwegian User Support and Operations Center during the experiment. The position of the root tip and the root curvature were analyzed as a function of time. It has been shown that in microgravity, the embryonic root curved strongly away from the cotyledons (automorphogenesis) and then straightened out slowly from 17 to 30 h following hydration (autotropism). Because of the autotropic straightening of roots in microgravity, their tip was oriented at an angle close to the optimal angle of curvature (120°,135°) for a period of 2 h during centrifugation. Moreover, it has been demonstrated that lentil roots grown in microgravity before stimulation were more sensitive than roots grown in 1 g. In these conditions, the threshold acceleration perceived by these organs was found to be between 0 and 2.0 × 10,3 g and estimated punctually at 1.4 × 10,5 g by using the hyperbolic model for fitting the experimental data and by assuming that autotropism had no or little impact on the gravitropic response. Gravisensing by statoliths should be possible at such a low level of acceleration because the actomyosin system could provide the necessary work to overcome the activation energy for gravisensing. [source]

The Impact of APROC on Taiwan's Economy: A CGEAnalysis of Deregulation

ASIAN ECONOMIC JOURNAL, Issue 1 2002
Shiu-Tung Wang
The Taiwan Government defines the Asia-Pacific Regional Operations Center (APROC) project as designed ,to transform Taiwan into a regional economic center through overall liberalization and internationalization'. From this definition and the targets of APROC as set by the Taiwan Government, it is not difficult to see that deregulation is one of the basic means of achieving its goals. In this paper, we use a computable general equilibrium (CGE) model to evaluate the possible effects of this deregulation. The effects of deregulation on the economy go through four channels in the model: (i) deregulation liberalizes the market; (ii) deregulation moderates factor market distortion; (iii) deregulation attracts foreign investment, speeds up capital accumulation and enlarges capital stock in Taiwan; and (iv) deregulation attracts foreign investment and hence improves technology. Six simulations are conducted in this paper. All of the simulations show positive effects on Taiwan's economy as a whole, while for individual sectors the effects are various. [source]

Local helioseismology in the SDO HMI/AIA data analysis pipeline

ASTRONOMISCHE NACHRICHTEN, Issue 3-4 2007
R. S. Bogart
Abstract Local helioseismology techniques will play a principal role in the pipeline processing of data from HMI to produce standard data products suitable for scientific analysis. Many of these techniques are undergoing rapid development, and it is expected that new or enhanced algorithms and models will be contributed by members of the community. We describe the design and implementation of the data analysis environment of the SDO Joint Science Operations Center for the benefit of potential contributors and users. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Incident Command System as a Response Model Within Emergency Operation Centers during Hurricane Rita

JOURNAL OF CONTINGENCIES AND CRISIS MANAGEMENT, Issue 3 2008
Leslie D. Lutz
This study examines the degree to which the use of the Incident Command System (ICS) influenced the performance of Texas emergency operations centers (EOCs) during Hurricane Rita. Staff in evacuation, transition, and host county EOCs completed a questionnaire that assessed demographic variables, EOC physical environment, ICS experience, ICS implementation, and team climate. The results indicated that the duties each ICS section performed varied substantially from one EOC to another. Moreover, ICS experience and ICS implementation lacked statistically significant correlations with team climate, even though EOCs' physical environments did. Finally, staff from emergency relevant agencies (e.g., public works and social services) seemed to have more problems with ICS than did staff from emergency mission agencies (e.g., fire and police departments). Thus, there needs to be further study of ICS application in emergencies other than structural and wildland fires, as well as the development of new ICS training materials for emergency relevant agencies to supplement the current ICS training materials for emergency mission agencies. [source]