UNT Libraries Government Documents Department - 65 Matching Results

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Analysis and Classification of Mammography Reports Using Maximum Variation Sampling

Description: Currently, no automated means of detecting abnormal mammograms exist. While knowledge discovery capabilities through data mining and data analytics tools are widespread in many industries, the healthcare industry as a whole lags far behind. Providers are only just beginning to recognize the value of data mining as a tool to analyze patient care and clinical outcomes. The research conducted by the authors investigates the use of genetic algorithms for classification of unstructured mammography reports, which can be later correlated to the images for extraction and testing. In mammography, much effort has been expended to characterize findings in the radiology reports. Various computer-assisted technologies have been developed to assist radiologists in detecting cancer; however, the algorithms still lack high degrees of sensitivity and specificity, and must undergo machine learning against a training set with known pathologies in order to further refine the algorithms with higher validity of truth. In a large database of reports and corresponding images, automated tools are needed just to determine which data to include in the training set. Validation of these data is another issue. Radiologists disagree with each other over the characteristics and features of what constitutes a normal mammogram and the terminology to use in the associated radiology report. Abnormal reports follow the lexicon established by the American College of radiology Breast Imaging Reporting and Data System (Bi-RADS), but even within these reports, there is a high degree of text variability and interpretation of semantics. The focus has been on classifying abnormal or suspicious reports, but even this process needs further layers of clustering and gradation, so that individual lesions can be more effectively classified. The tools that are needed will not only help further identify problem areas but also support risk assessment and other knowledge discovery applications. The knowledge to be gained by extracting ...
Date: January 1, 2011
Creator: Patton, Robert M.; Beckerman, Barbara G. & Potok, Thomas E.

Atomic-Resolution STEM at Low Primary Energies

Description: Aberration-corrected scanning transmission electron microscopes (STEMs) can now produce electron probes as small as 1 {angstrom} at 60 keV. This level of performance allows individual light atoms to be imaged in various novel materials including graphene, monolayer boron nitride, and carbon nanotubes. Operation at 60 keV avoids direct knock-on damage in such materials, but some radiation damage often remains, and limits the maximum usable electron dose. Elemental identification by electron energy loss spectroscopy (EELS) is then usefully supplemented by annular dark-field (ADF) imaging, for which the signal is much larger and the spatial resolution significantly better. Because of its strong dependence on the atomic number Z, ADF can be used to identify the chemical type of individual atoms, both heavy and light. We review the instrumental requirements for atomic resolution imaging at 60 keV and lower energies, and we illustrate the kinds of studies that have now become possible by ADF images of graphene, monolayer BN, and single-wall carbon nanotubes, and by ADF images and EEL spectra of carbon nanotubes containing nanopods filled with single atoms of Er. We then discuss likely future developments.
Date: January 1, 2011
Creator: Krivanek, Ondrej L.; Chisholm, Matthew F; Dellby, N. & Murfitt, M. F.

Bioananalytics of Human Microdosing

Description: Abstract not provided
Date: May 2, 2011
Creator: Buchholz, B. A.; Sarachine Falso, M. J.; Stewart, B. J.; Haack, K. W.; Ognibene, T. J.; Salazar Quintero, G. A. et al.

Biofuel Economics

Description: As concerns regarding increasing energy prices, global warming and renewable resources continue to grow, so has scientific discovery into agricultural biomass conversion. Plant Biomass Conversion addresses both the development of plant biomass and conversion technology, in addition to issues surrounding biomass conversion, such as the affect on water resources and soil sustainability. This book also offers a brief overview of the current status of the industry and examples of production plants being used in current biomass conversion efforts.
Date: July 15, 2011
Creator: Klein-Marcuschamer, Daniel; Holmes, Brad; Simmons, Blake & Blanch, Harvey

Cases Adjudged in The Supreme Court at October Term, 2006

Description: Volume of the United States Reports containing the final decisions and opinions of the Supreme Court justices regarding cases between June 4 and September 28, 2007. Also includes notes regarding the members of the Supreme Court, orders, and other relevant materials. Index starts on page 1277.
Date: 2011
Creator: Wagner, Frank D.

Cases Adjudged in The Supreme Court at October Term, 2007

Description: Volume of the United States Reports containing the final decisions and opinions of the Supreme Court justices regarding cases between October 1, 2007, and April 14, 2008. Also includes notes regarding the members of the Supreme Court, orders, and other relevant materials. Index starts on page 1335.
Date: 2011
Creator: Wagner, Frank D.

Challenges in Data Intensive Analysis at Scientific Experimental User Facilities

Description: 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 techniques provides scientists with the ability to research structures and processes at various levels of theory, e.g. providing molecular 'movies' of complex reactions that show bond breaking and reforming in natural time scales, along with the intermediate states to understand the mechanisms that govern the chemical transformations. This chapter will discuss the critical data intensive analysis challenges faced by the experimental science community at large scale and laboratory based facilities. The chapter will highlight current solutions and lay out perspectives for the future, such as methods to achieve real time analysis capabilities and the challenges and opportunities of data integration ...
Date: January 1, 2011
Creator: Kleese Van Dam, Kerstin; Li, Dongsheng; Cobb, John W; Green, Mark L; Burley, Catherine L & Miller, Stephen D

Comparative assessment of status and opportunities for carbon Dioxide Capture and storage and Radioactive Waste Disposal In North America

Description: Aside from the target storage regions being underground, geologic carbon sequestration (GCS) and radioactive waste disposal (RWD) share little in common in North America. The large volume of carbon dioxide (CO{sub 2}) needed to be sequestered along with its relatively benign health effects present a sharp contrast to the limited volumes and hazardous nature of high-level radioactive waste (RW). There is well-documented capacity in North America for 100 years or more of sequestration of CO{sub 2} from coal-fired power plants. Aside from economics, the challenges of GCS include lack of fully established legal and regulatory framework for ownership of injected CO{sub 2}, the need for an expanded pipeline infrastructure, and public acceptance of the technology. As for RW, the USA had proposed the unsaturated tuffs of Yucca Mountain, Nevada, as the region's first high-level RWD site before removing it from consideration in early 2009. The Canadian RW program is currently evolving with options that range from geologic disposal to both decentralized and centralized permanent storage in surface facilities. Both the USA and Canada have established legal and regulatory frameworks for RWD. The most challenging technical issue for RWD is the need to predict repository performance on extremely long time scales (10{sup 4}-10{sup 6} years). While attitudes toward nuclear power are rapidly changing as fossil-fuel costs soar and changes in climate occur, public perception remains the most serious challenge to opening RW repositories. Because of the many significant differences between RWD and GCS, there is little that can be shared between them from regulatory, legal, transportation, or economic perspectives. As for public perception, there is currently an opportunity to engage the public on the benefits and risks of both GCS and RWD as they learn more about the urgent energy-climate crisis created by greenhouse gas emissions from current fossil-fuel combustion practices.
Date: July 22, 2011
Creator: Oldenburg, C. & Birkholzer, J.T.

Composite Materials under Extreme Radiation and Temperature Environments of the Next Generation Nuclear Reactors

Description: In the nuclear energy renaissance, driven by fission reactor concepts utilizing very high temperatures and fast neutron spectra, materials with enhanced performance that exceeds are expected to play a central role. With the operating temperatures of the Generation III reactors bringing the classical reactor materials close to their performance limits there is an urgent need to develop and qualify new alloys and composites. Efforts have been focused on the intricate relations and the high demands placed on materials at the anticipated extreme states within the next generation fusion and fission reactors which combine high radiation fluxes, elevated temperatures and aggressive environments. While nuclear reactors have been in operation for several decades, the structural materials associated with the next generation options need to endure much higher temperatures (1200 C), higher neutron doses (tens of displacements per atom, dpa), and extremely corrosive environments, which are beyond the experience on materials accumulated to-date. The most important consideration is the performance and reliability of structural materials for both in-core and out-of-core functions. While there exists a great body of nuclear materials research and operating experience/performance from fission reactors where epithermal and thermal neutrons interact with materials and alter their physio-mechanical properties, a process that is well understood by now, there are no operating or even experimental facilities that will facilitate the extreme conditions of flux and temperature anticipated and thus provide insights into the behaviour of these well understood materials. Materials, however, still need to be developed and their interaction and damage potential or lifetime to be quantified for the next generation nuclear energy. Based on material development advances, composites, and in particular ceramic composites, seem to inherently possess properties suitable for key functions within the operating envelope of both fission and fusion reactors. In advanced fission reactors composite materials are being designed in ...
Date: May 1, 2011
Creator: Simos, N.

Cyber Security and Information Intelligence Research Workshop (CSIIRW'11) Proceedings

Description: The energy industry is embarking upon an infrastructure transformation that will result in a national power grid that is more intelligent, robust, resilient, and secure. While the final form will not be known for quite some time, clearly a smarter grid will make better use of information. Whether an electric utility is making real-time adjustments in response to changing load conditions, or commercial and private consumers are making better choices, the timely availability of this information will become increasingly critical. Ultimately, the overall efficiency, reliability, and resilience of the grid is inextricably linked to information. Unfortunately, "the electric power sector is second from the bottom of all major U.S. industries in terms of R&D spending as a percentage of revenue, exceeding only pulp and paper [Amin2011]." Moreover, U.S. officials worry that cyber-spies could use their [demonstrated] access to shut down the grid or take control of power plants during a time of crisis or war [CIO09, WSJ09]. Moreover, Massachusetts Institute of Technology (MIT) released the results of a two-year study, The Future of the Electric Grid.
Date: January 1, 2011
Creator: Sheldon, Frederick T; Abercrombie, Robert K & Krings, Axel

Deep Water: the Gulf Oil Disaster and the Future of Offshore Drilling

Description: On May 22, 2010, President Barack Obama announced the creation of the National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling: an independent,nonpartisan entity, directed to provide a thorough analysis and impartial judgment. The President charged the Commission to determine the causes of the disaster, and to improve the country’s ability to respond to spills, and to recommend reforms to make offshore energy production safer. This report is the result of an intense six-month effort to fulfill the President’s charge. The Commission’s report offers the President, policymakers, industry, and the American people the fullest account available of the largest oil spill in U.S history: the context for the well itself, how the explosion and spill happened, and how industry and government scrambled to respond to an unprecedented emergency.
Date: January 2011
Creator: National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling (U.S.)