Network Communication as a Service-Oriented Capability (open access)

Network Communication as a Service-Oriented Capability

In widely distributed systems generally, and in science-oriented Grids in particular, software, CPU time, storage, etc., are treated as"services" -- they can be allocated and used with service guarantees that allows them to be integrated into systems that perform complex tasks. Network communication is currently not a service -- it is provided, in general, as a"best effort" capability with no guarantees and only statistical predictability. In order for Grids (and most types of systems with widely distributed components) to be successful in performing the sustained, complex tasks of large-scale science -- e.g., the multi-disciplinary simulation of next generation climate modeling and management and analysis of the petabytes of data that will come from the next generation of scientific instrument (which is very soon for the LHC at CERN) -- networks must provide communication capability that is service-oriented: That is it must be configurable, schedulable, predictable, and reliable. In order to accomplish this, the research and education network community is undertaking a strategy that involves changes in network architecture to support multiple classes of service; development and deployment of service-oriented communication services, and; monitoring and reporting in a form that is directly useful to the application-oriented system so that it may …
Date: January 8, 2008
Creator: Johnston, William; Johnston, William; Metzger, Joe; Collins, Michael; Burrescia, Joseph; Dart, Eli et al.
System: The UNT Digital Library
PET IMAGING STUDIES IN DRUG ABUSE RESEARCH. (open access)

PET IMAGING STUDIES IN DRUG ABUSE RESEARCH.

There is overwhelming evidence that addiction is a disease of the brain (Leshner, 1997). Yet public perception that addiction is a reflection of moral weakness or a lack of willpower persists. The insidious consequence of this perception is that we lose sight of the fact that there are enormous medical consequences of addiction including the fact that a large fraction of the total deaths from cancer and heart disease are caused by smoking addiction. Ironically the medical school that educates physicians in addiction medicine and the cancer hospital that has a smoking cessation clinic are vanishingly rare and efforts at harm reduction are frequently met with a public indignation. Meanwhile the number of people addicted to substances is enormous and increasing particularly the addictions to cigarettes and alcohol. It is particularly tragic that addiction usually begins in adolescence and becomes a chronic relapsing problem and there are basically no completely effective treatments. Clearly we need to understand how drugs of abuse affect the brain and we need to be creative in using this information to develop effective treatments. Imaging technologies have played a major role in the conceptualization of addiction as a disease of the brain (Fowler et al., 1998a; …
Date: January 29, 2001
Creator: Fowler, J. S.; Volkow, N. D.; Ding, Y. S.; Logan, J. & Wang, G. J.
System: The UNT Digital Library
Challenges in Data Intensive Analysis at Scientific Experimental User Facilities (open access)

Challenges in Data Intensive Analysis at Scientific Experimental User Facilities

Today's scientific challenges such as routes to a sustainable energy future, materials by design or biological and chemical environmental remediation methods, are complex problems that require the integration of a wide range of complementary expertise to be addressed successfully. Experimental and computational science research methods can hereby offer fundamental insights for their solution. Experimental facilities in particular can contribute through a large variety of investigative methods, which can span length scales from millions of kilometers (radar) to the sub-nucleus (LHC). These methods are used to probe structure, properties, and function of objects from single elements to whole communities. Hereby direct imaging techniques are a powerful means to develop an atomistic understanding of scientific issues. For example, the identification ofmechanisms associated with chemical, material, and biological transformations requires the direct observation of the reactions to build up an understanding of the atom-by-atom structural and chemical changes. Computational science can aid the planning of such experiments, correlate results, explain or predict the phenomena as they would be observed and thus aid their interpretation. Furthermore computational science can be essential for the investigation of phenomena that are difficult to observe due to their scale, reaction time or extreme conditions. Combining experimental and computational …
Date: January 1, 2011
Creator: Kleese Van Dam, Kerstin; Li, Dongsheng; Cobb, John W; Green, Mark L; Burley, Catherine L & Miller, Stephen D
System: The UNT Digital Library
Data Analysis for Real Time Identification of Grid Disruptions (open access)

Data Analysis for Real Time Identification of Grid Disruptions

The U.S. electric power system comprises multiple distinct interconnections of generators, high voltage transmission systems, and local distribution systems that maintain a continuous balance between generation and load with impressive levels of efficiency and reliability. This critical infrastructure has served the nation remarkably well, but is likely to see more changes over the next decade than it has seen over the past century. In particular, the widespread deployment of renewable generation, smart-grid controls, energy storage, and new conducting materials will require fundamental changes in grid planning and the way we run the power grid. Two challenges in the realization of the smart grid technology are the ability to visualize the deluge of expected data streams for global situational awareness; as well as the ability to detect disruptive and classify such events from spatially-distributed high-speed power system frequency measurements. One element of smart grid technology is the installation of a wide-area frequency measurement system on the electric poles in the streets for conditions monitoring of the distribution lines. This would provide frequency measurements about the status of the electric grid and possible information about impending problems before they start compounding and cascading. The ability to monitor the distribution lines is just …
Date: January 1, 2012
Creator: Chandola, Varun; Omitaomu, Olufemi A & Fernandez, Steven J
System: The UNT Digital Library
Quality Assessment of Retinal Fundus Images using Elliptical Local Vessel Density (open access)

Quality Assessment of Retinal Fundus Images using Elliptical Local Vessel Density

Diabetic retinopathy is the leading cause of blindness in the Western world. The World Health Organisation estimates that 135 million people have diabetes mellitus worldwide and that the number of people with diabetes will increase to 300 million by the year 2025 (Amos et al., 1997). Timely detection and treatment for DR prevents severe visual loss in more than 50% of the patients (ETDRS, 1991). Through computer simulations is possible to demonstrate that prevention and treatment are relatively inexpensive if compared to the health care and rehabilitation costs incurred by visual loss or blindness (Javitt et al., 1994). The shortage of ophthalmologists and the continuous increase of the diabetic population limits the screening capability for effective timing of sight-saving treatment of typical manual methods. Therefore, an automatic or semi-automatic system able to detect various type of retinopathy is a vital necessity to save many sight-years in the population. According to Luzio et al. (2004) the preferred way to detect diseases such as diabetic retinopathy is digital fundus camera imaging. This allows the image to be enhanced, stored and retrieved more easily than film. In addition, images may be transferred electronically to other sites where a retinal specialist or an automated …
Date: January 1, 2010
Creator: Giancardo, Luca; Meriaudeau, Fabrice; Karnowski, Thomas Paul; Chaum, Edward & Tobin Jr, Kenneth William
System: The UNT Digital Library
Genome Sequence Databases (Overview): Sequencing and Assembly (open access)

Genome Sequence Databases (Overview): Sequencing and Assembly

From the date its role in heredity was discovered, DNA has been generating interest among scientists from different fields of knowledge: physicists have studied the three dimensional structure of the DNA molecule, biologists tried to decode the secrets of life hidden within these long molecules, and technologists invent and improve methods of DNA analysis. The analysis of the nucleotide sequence of DNA occupies a special place among the methods developed. Thanks to the variety of sequencing technologies available, the process of decoding the sequence of genomic DNA (or whole genome sequencing) has become robust and inexpensive. Meanwhile the assembly of whole genome sequences remains a challenging task. In addition to the need to assemble millions of DNA fragments of different length (from 35 bp (Solexa) to 800 bp (Sanger)), great interest in analysis of microbial communities (metagenomes) of different complexities raises new problems and pushes some new requirements for sequence assembly tools to the forefront. The genome assembly process can be divided into two steps: draft assembly and assembly improvement (finishing). Despite the fact that automatically performed assembly (or draft assembly) is capable of covering up to 98% of the genome, in most cases, it still contains incorrectly assembled reads. …
Date: January 1, 2009
Creator: Lapidus, Alla L.
System: The UNT Digital Library
EVAPORITE MICROBIAL FILMS, MATS, MICROBIALITES AND STROMATOLITES (open access)

EVAPORITE MICROBIAL FILMS, MATS, MICROBIALITES AND STROMATOLITES

Evaporitic environments are found in a variety of depositional environments as early as the Archean. The depositional settings, microbial community and mineralogical composition vary significantly as no two settings are identical. The common thread linking all of the settings is that evaporation exceeds precipitation resulting in elevated concentrations of cations and anions that are higher than in oceanic systems. The Dead Sea and Storrs Lake are examples of two diverse modern evaporitic settings as the former is below sea level and the latter is a coastal lake on an island in the Caribbean. Each system varies in water chemistry as the Dead Sea dissolved ions originate from surface weathered materials, springs, and aquifers while Storrs Lake dissolved ion concentration is primarily derived from sea water. Consequently some of the ions, i.e., Sr, Ba are found at significantly lower concentrations in Storrs Lake than in the Dead Sea. The origin of the dissolved ions are ultimately responsible for the pH of each system, alkaline versus mildly acidic. Each system exhibits unique biogeochemical properties as the extreme environments select certain microorganisms. Storrs Lake possesses significant biofilms and stromatolitic deposits and the alkalinity varies depending on rainfall and storm activity. The microbial community …
Date: January 28, 2008
Creator: Brigmon, R; Penny Morris, P & Garriet Smith, G
System: The UNT Digital Library
Geodynamics Project. US progress report, 1977 (open access)

Geodynamics Project. US progress report, 1977

Past work of the US Geodynamics Committee (USGC) is summarized. The USGC devoted considerable discussion at its November 1976, meeting to preparation of an up-to-date statement of the USGC actions developed by USGC reporters. That discussion ultimately led to a number of statements and recommendations, given here. The bulk of this document is comprised of the reporters' reports on the following topics: fine structure of the crust and upper mantle, evolution of oceanic lithosphere, internal processes and properties, crystal growing, large-volume experimentation, application of isotope geochemistry to geodynamics, geodynamic modeling, drilling for scientific purposes, plate boundaries, plate interiors, data centers and repositories, geodynamic activities in the Caribbean area, seismicity and deep structure of the continental margin, and aeromagnetic survey. Appendixes give project correspondents, participants, etc. 23 figures, 2 tables. (RWR)
Date: January 1, 1977
Creator: unknown
System: The UNT Digital Library
State Energy Program Operations Manual (Revised) (open access)

State Energy Program Operations Manual (Revised)

This manual outlines and explains in detail, the procedures state energy offices need to follow to receive grants from the U.S. Department of Energy under its State Energy Program (SEP).
Date: January 1, 2003
Creator: unknown
System: The UNT Digital Library