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Modeling for Integrating Science and Management

Description: Modeling relationships between land-management practices and resulting changes in carbon, nitrogen, albedo, and other factors is complex. Even so, such modeling can be used to integrate scientific knowledge and provide a bridge between scientific understanding and policy. Yet, too often decision makers have a poor understanding of the underlying models and thus may misinterpret the implications. More often, decision makers diminish model results as fictitious, for they do not recognize the validity or extent of the underlying science. Decision makers should understand that the modeling process (1) involves formalizing hypotheses concerning relationships among components of human, biophysical, and ecological systems and (2) fosters exploration of implications of those hypotheses. To be most helpful for decision making, developing a model requires documentation of the model components and implications including all assumptions, input and output variables, and methods used to calibrate and validate the model as well as to identify sensitivities and uncertainties. There is no one modeling approach that meets the diverse needs of decision makers regarding land and carbon issues. As with all scientific explorations, new learning typically results in improved understanding, new questions, and revised hypotheses about the way the system works. Decision makers need to realize that models cannot provide specific predictions any more than models are to be believed. Instead, modeling enhances understanding of a system by requiring a formal statement of what is known and not known. The advantages and cautionary principles involved in using models for decision making are discussed. Because land change is a local or regional process and many questions about the effect of these changes are at the global scale, there are still gaps in modeling land change and its effects. The chapter concludes with opportunities to improve modeling of land change and the carbon cycle so that the scientific understanding and ...
Date: January 1, 2013
Creator: Dale, Virginia H. & Kline, Keith L.
Partner: UNT Libraries Government Documents Department

The Motif Tool Assessment Platform (MTAP) for Sequence-Based Transcription Factor Binding Site Prediction Tools.

Description: Predicting transcription factor binding sites (TFBS) from sequence is one of the most challenging problems in computational biology. The development of (semi-)automated computer-assisted prediction methods are needed to find TFBS over an entire genome, which is a first step in reconstructing mechanisms that controls gene activity. Bioinformatics journals continue to publish diverse methods for predicting TFBS on a monthly basis. To help practitioners in deciding which method to use to predict for a particular TFBS, we provide a platform to assess the quality and applicability of the available methods. Assessment tools allow researchers to determine how methods can be expected to perform on specific organisms or on specific transcription factor families. This chapter introduces the TFBS detection problem and reviews current strategies for evaluating algorithm effectiveness. In this chapter, a novel and robust assessment tool, the Motif Tool Assessment Platform (MTAP) is introduced and discussed.
Date: January 2010
Creator: Quest, Daniel J. & Ali, Hesham
Partner: UNT Libraries Government Documents Department

U.S. Patent 8,304,670, Portable Weighing System with Alignment Features

Description: A system for weighing a load is disclosed. The weighing system includes a pad having at least one transducer for weighing a load disposed on the pad. In some embodiments the pad has a plurality of foot members and the weighing system may include a plate that disposed underneath the pad for receiving the plurality of foot members and for aligning the foot members when the weighing system is installed. The weighing system may include a spacer disposed adjacent the pad and in some embodiments, a spacer anchor operatively secures the spacer to a support surface, such as a plate, a railway bed, or a roadway. In some embodiments the spacer anchor operatively secures both the spacer and the pad to a roadway.
Date: January 1, 2012
Creator: Abercrombie, Robert K; Richardson, Gregory; Scudiere, Matthew B & Sheldon, Frederick T
Partner: UNT Libraries Government Documents Department

U.S. Patent 8,389,878, Weigh-in-Motion Scale with Foot Alignment Features

Description: A pad is disclosed for use in a weighing system for weighing a load. The pad includes a weighing platform, load cells, and foot members. Improvements to the pad reduce or substantially eliminate rotation of one or more of the corner foot members. A flexible foot strap disposed between the corner foot members reduces rotation of the respective foot members about vertical axes through the corner foot members and couples the corner foot members such that rotation of one corner foot member results in substantially the same amount of rotation of the other comer foot member. In a strapless variant one or more fasteners prevents substantially all rotation of a foot member. In a diagonal variant, a foot strap extends between a corner foot member and the weighing platform to reduce rotation of the foot member about a vertical axis through the comer foot member.
Date: January 1, 2013
Creator: Abercrombie, Robert K; Richardson, Gregory & Scudiere, Matthew B
Partner: UNT Libraries Government Documents Department

Who's In The Dark: Satellite Based Estimates Of Electrification Rates

Description: A technique has been developed to estimate the percent population having electric power access based on the presence of satellite detected nighttime lighting. A global survey was conducted for the year 2006 using nighttime lights collected by the U.S. Air Force Defense Meteorological Satellite Program (DMSP) in combination with the U.S. Department of Energy Landscan population dataset. The survey includes results for 229 countries and more than 2000 subnational units. The results are compared to reported electrification rates for 87 countries compiled from a variety of sources by the International Energy Agency. The DMSP derived estimate of number of people worldwide who lack access to electricity is 1.62 billion, only slightly larger than the 1.58 billion estimated by the International Energy Agency.
Date: January 1, 2011
Creator: Elvidge, Christopher D.; Baugh, Kimberly E.; Sutton, Paul S.; Bhaduri, Budhendra L; Tuttle, Benjamin T.; Ghosh, Tilottama et al.
Partner: UNT Libraries Government Documents Department

CFD Simulation of Airflow in Ventilated Wall System Report #9

Description: The objective of this report was to examine air movements in vinyl and brick ventilation cavities in detail, using a state of the art CFD commercial modeling tool. The CFD activity was planned to proceed the other activities in order to develop insight on the important magnitudes of scales occurring during ventilation air flow. This information generated by the CFD model was to be used to modify (if necessary) and to validate the air flow dynamics already imbedded in the hygrothermal model for the computer-based air flow simulation procedures. A comprehensive program of advanced, state-of-the-art hygrothermal modeling was then envisaged mainly to extend the knowledge to other wall systems and at least six representative climatic areas. These data were then to be used to provide the basis for the development of design guidelines. CFD results provided timely and much needed answers to many of the concerns and questions related to ventilation flows due to thermal buoyancy and wind-driven flow scenarios. The relative strength between these two mechanisms. Simple correlations were developed and are presented in the report providing the overall pressure drop, and flow through various cavities under different exterior solar and temperature scenarios. Brick Rainscreen Wall: It was initially expected that a 50 mm cavity would offer reduced pressure drops and increased air flow compared to a 19 mm cavity. However, these models showed that the size of the ventilation slots through the wall are the limiting factor rather than the cavity depth. Of course, once the slots are enlarged beyond a certain point, this could change. The effects of natural convection within the air cavities, driven by the temperature difference across the cavity, were shown to be less important than the external wind speed (for a wind direction normal to the wall surface), when wind action is present. ...
Date: January 1, 2004
Creator: Stovall, Therese K & Karagiozis, Achilles N
Partner: UNT Libraries Government Documents Department

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
Partner: UNT Libraries Government Documents Department

HIGH PERFORMANCE PLASMAS ON THE NATIONAL SPHERICAL TORUS EXPERIMENT

Description: The National Spherical Torus Experiment has produced toroidal plasmas at low aspect ratio (A = R/a = 0.86d0.68m - 1.3, where R is the major radius and a is the minor radius of the torus) with plasma currents of 1.4MA. The rapid development of the machine has led to very exciting physics results during the first full year of physics operation. Pulse lengths in excess of 0.5s have been obtained with inductive current drive. Up to 4MW of High Harmonic Fast Wave (HHFW) heating power has been applied with 6MW planned. Using only 2MW of HHFW heating power clear evidence of electron heating is sden with HHFW, as observed by the multi point Thomson scattering diagnostic. A non-inductive current drive concept known as Coaxial Helicity Injection (CHI) has driven 260kA of toroidal current. Neutral beam heating power of 5MW has been injected. Plasmas with PI ( =2p0<p>/B2 = a measure of magnetic confinement efficiency) of 22% have been achieved, as calculated using the EFIT equilibrium reconstruction code. P limiting phenomena have been observed, and the maximum p, scales with I&z& High frequency (>MHz) magnetic fluctuations have been observed. H-mode plasmas are observed with confinement times of > 100ms. Beam heated plasmas show energy confinement times in excess of those predicted by empirical scaling expressions. Ion temperatures in excess of 2.OkeV have been measured, and power balance suggests that the power loss from the ions to the electrons may exceed the calculated classical input power to the ions.
Date: January 1, 2001
Creator: Gates, D. & Peng, Yueng Kay Martin
Partner: UNT Libraries Government Documents Department

Primary Radiation Damage Formation

Description: The physical processes that give rise to changes in the microstructure, and the physical and mechanical properties of materials exposed to energetic particles are initiated by essentially elastic collisions between atoms in what has been called an atomic displacement cascade. The formation and evolution of this primary radiation damage mechanism are described to provide an overview of how stable defects are formed by displacement cascades, as well as the nature and morphology of the defects themselves. The impact of the primary variables cascade energy and irradiation temperature are discussed, along with a range of secondary factors that can influence damage formation.
Date: January 1, 2012
Creator: Stoller, Roger E
Partner: UNT Libraries Government Documents Department

Radiation Damage Theory

Description: This chapter presents an overview of basic radiation damage theory, including older and more recent models, to provide framework, within which radiation effects, such as void swelling, can be rationalized. A complete review of the literature is not attempted, but sufficient references are given to provide a decent introduction to a quite large number of publications in the field. Many derivations are different from and, in our view, more elegant than in the original publications. The work is directed to both theoreticians and experimentalists, and, especially, to those passionate individuals who are going to take the radiation damage theory (RDT) to the future.
Date: January 1, 2012
Creator: Golubov, Stanislav I; Barashev, Aleksandr & Stoller, Roger E
Partner: UNT Libraries Government Documents Department

Plant Cell Walls: Basics of Structure, Chemistry, Accessibility and the Influence on Conversion - Aqueous Pretreatment of Plant Biomass for Biological and Chemical Conversion to Fuels and Chemicals

Description: This book is focused on the pretreatment of biomass, a necessary step for efficient conversion of the plant cell wall materials to fuels and other products. Pretreatment is required because it is difficult to access, separate, and release the monomeric sugars comprising the biopolymers within the biomass that can be further upgraded to products through chemical processes such as aqueous phase reforming or biological routes such as fermentation of the sugars to ethanol This resistance to degradation or difficulty to release the monomers (mostly sugars) is commonly referred to as recalcitrance. There are many methods to overcome plant recalcitrance, but the underlying cause of the recalcitrance lies in the complex combination of chemical and structural features of the plant cell walls.
Date: January 1, 2013
Creator: Davison, Brian H; Davis, Dr. Mark F.; Parks, Jerry M & Donohoe, Bryan
Partner: UNT Libraries Government Documents Department