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High-Fidelity Geometric Modelling for Biomedical Applications (open access)

High-Fidelity Geometric Modelling for Biomedical Applications

We describe a combination of algorithms for high fidelity geometric modeling and mesh generation. Although our methods and implementations are application-neutral, our primary target application is multiscale biomedical models that range in scales across the molecular, cellular, and organ levels. Our software toolchain implementing these algorithms is general in the sense that it can take as input a molecule in PDB/PQR forms, a 3D scalar volume, or a user-defined triangular surface mesh that may have very low quality. The main goal of our work presented is to generate high quality and smooth surface triangulations from the aforementioned inputs, and to reduce the mesh sizes by mesh coarsening. Tetrahedral meshes are also generated for finite element analysis in biomedical applications. Experiments on a number of bio-structures are demonstrated, showing that our approach possesses several desirable properties: feature-preservation, local adaptivity, high quality, and smoothness (for surface meshes). The availability of this software toolchain will give researchers in computational biomedicine and other modeling areas access to higher-fidelity geometric models.
Date: April 1, 2008
Creator: Zeyun Yu, Michael Holst, and J.A. McCammon
Object Type: Article
System: The UNT Digital Library
Homebuilder's Guide to Going Solar (Brochure) (open access)

Homebuilder's Guide to Going Solar (Brochure)

A Homebuilder's Guide to Going Solar is designed to help you assess the benefits to your business and customers of installing solar equipment or making your houses solar-ready. The information comes from studies of builders who have successfully integrated solar into their operations as well as conversations with builders and solar professionals. These studies and conversations indicate that builders want to know: (1) Do solar economics work in my area? (2) If not, are there other reasons to go solar?; and (3) Is there a local support system of solar professionals I can call on to help me integrate solar seamlessly into my projects? This effort to educate builders about solar is a work in progress.
Date: April 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Idaho National Laboratory Environmental Monitoring Plan (open access)

Idaho National Laboratory Environmental Monitoring Plan

This plan describes environmental monitoring as required by U.S. Department of Energy (DOE) Order 450.1, “Environmental Protection Program,” and additional environmental monitoring currently performed by other organizations in and around the Idaho National Laboratory (INL). The objective of DOE Order 450.1 is to implement sound stewardship practices that protect the air, water, land, and other natural and cultural resources that may be impacted by DOE operations. This plan describes the organizations responsible for conducting environmental monitoring across the INL, the rationale for monitoring, the types of media being monitored, where the monitoring is conducted, and where monitoring results can be obtained. This plan presents a summary of the overall environmental monitoring performed in and around the INL without duplicating detailed information in the various monitoring procedures and program plans currently used to conduct monitoring.
Date: April 1, 2008
Creator: Knight, Joanne L.
Object Type: Report
System: The UNT Digital Library
Improving Air Quality with Solar Energy (open access)

Improving Air Quality with Solar Energy

This fact sheet series highlights how renewable energy and energy efficiency technologies can and are being used to reduce air emissions and meet environmental goals, showcasing case studies and technology-specific topics. This one focus on solar energy technologies.
Date: April 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
INL Active Interrogation Testing In Support of the GNEP Safeguards Campaign (open access)

INL Active Interrogation Testing In Support of the GNEP Safeguards Campaign

Active interrogation, a measurement technique which uses a radiation source to probe materials and generate unique signatures useful for characterizing those materials, is a powerful tool for assaying special nuclear material. Work at Idaho National Laboratory (INL) in the area of active interrogation, using neutron and photon sources, has been under way for many years to develop methods for detecting and quantifying nuclear material for national and homeland security research areas. This research knowledge base is now being extended to address nuclear safeguards and process monitoring issues related to the Global Nuclear Energy Partnership (GNEP). As a first step in this area preliminary scoping studies have been performed to investigate the usefulness of using active neutron interrogation, with a low-power electronic neutron generator, to assay Department of Transportation 6M shipping drums containing uranium oxide fuel rodlets from INL’s zero power physics reactor. Using the paired-counting technique during the die-away time period of interrogation, a lower detection limit of approximately 4.2 grams of enriched uranium (40% 235U) was calculated for a 40 minute measurement using a field portable 2.5 MeV neutron source and an array of 16 moderated helium-3 neutron tubes. Future work in this area, including the use of a …
Date: April 1, 2008
Creator: Chichester, David L.
Object Type: Report
System: The UNT Digital Library
An Innovative Hybrid Loop-Pool SFR Design and Safety Analysis Methods: Today and Tomorrow (open access)

An Innovative Hybrid Loop-Pool SFR Design and Safety Analysis Methods: Today and Tomorrow

Investment in commercial sodium cooled fast reactor (SFR) power plants will become possible only if SFRs achieve economic competitiveness as compared to light water reactors and other Generation IV reactors. Toward that end, we have launched efforts to improve the economics and safety of SFRs from the thermal design and safety analyses perspectives at Idaho National Laboratory. From the thermal design perspective, an innovative hybrid loop-pool SFR design has been proposed. This design takes advantage of the inherent safety of a pool design and the compactness of a loop design to further improve economics and safety. From the safety analyses perspective, we have initiated an effort to develop a high fidelity reactor system safety code.
Date: April 1, 2008
Creator: Zhang, Hongbin; Zhao, Haihua & Mousseau, Vincent
Object Type: Article
System: The UNT Digital Library
Intelligence Issues for Congress (open access)

Intelligence Issues for Congress

None
Date: April 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
An interaction-based access control model (IBAC) for collaborative services (open access)

An interaction-based access control model (IBAC) for collaborative services

A collaboration is a collection of services that work together to achieve a common goal. Although collaborations help when tackling difficult problems, they lead to security issues. First, a collaboration is often performed by services that are drawn from different security domains. Second, a service interacts with multiple peer services during the collaboration. These interactions are not isolated from one another--e.g., data may flow through a sequence of different services. As a result, a service is exposed to multiple peer services in varying degrees, leading to different security threats. We identify the types of interactions that can be present in collaborations, and discuss the security threats due to each type. We propose a model for representing the collaboration context so that a service can be made aware of the existing interactions. We provide an access control model for a service participating in a collaboration. We couple our access control model with a policy model, so that the access requirements from collaborations can be expressed and evaluated.
Date: April 1, 2008
Creator: Altunay, Mine; Byrd, Gregory T.; Brown, Doug E. & Dean, Ralph A.
Object Type: Article
System: The UNT Digital Library
Internal Control: Improvements Needed in SEC's Accounting and Financial Reporting Process (open access)

Internal Control: Improvements Needed in SEC's Accounting and Financial Reporting Process

Correspondence issued by the Government Accountability Office with an abstract that begins "On November 16, 2007, we issued our report on the U.S. Securities and Exchange Commission's (SEC) fiscal years 2007 and 2006 financial statements and on SEC's internal control as of September 30, 2007. We also reported on the results of our tests of SEC's compliance with selected provisions of laws and regulations during fiscal year 2007. The purpose of this report is to present areas of SEC's internal controls identified during our fiscal year 2007 audit that could be improved. This report contains 14 recommendations to SEC to improve these internal controls and procedures. These recommendations are in addition to those we already provided to SEC as a result of our prior audits of SEC's financial statements."
Date: April 1, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Intial synchroscan streak camera imaging at the A0 photoinjector (open access)

Intial synchroscan streak camera imaging at the A0 photoinjector

At the Fermilab A0 photoinjector facility, bunch-length measurements of the laser micropulse and the e-beam micropulse have been done in the past with a single-sweep module of the Hamamatsu C5680 streak camera with an intrinsic shot-to-shot trigger jitter of 10 to 20 ps. We have upgraded the camera system with the synchroscan module tuned to 81.25 MHz to provide synchronous summing capability with less than 1.5-ps FWHM trigger jitter and a phase-locked delay box to provide phase stability of {approx}1 ps over 10s of minutes. This allowed us to measure both the UV laser pulse train at 244 nm and the e-beam via optical transition radiation (OTR). Due to the low electron beam energies and OTR signals, we typically summed over 50 micropulses with 1 nC per micropulse. We also did electron beam bunch length vs. micropulse charge measurements to identify a significant e-beam micropulse elongation from 10 to 30 ps (FWHM) for charges from 1 to 4.6 nC. This effect is attributed to space-charge effects in the PC gun as reproduced by ASTRA calculations. Chromatic temporal dispersion effects in the optics were also characterized and will be reported.
Date: April 1, 2008
Creator: Lumpkin, A. H. & Ruan, J.
Object Type: Article
System: The UNT Digital Library
Inverse modeling and forecasting for the exploitation of the Pauzhetsky geothermal field, Kamchatka, Russia (open access)

Inverse modeling and forecasting for the exploitation of the Pauzhetsky geothermal field, Kamchatka, Russia

A three-dimensional numerical model of the Pauzhetsky geothermal field has been developed based on a conceptual hydrogeological model of the system. It extends over a 13.6-km2 area and includes three layers: (1) a base layer with inflow; (2) a geothermal reservoir; and (3) an upper layer with discharge and recharge/infiltration areas. Using the computer program iTOUGH2 (Finsterle, 2004), the model is calibrated to a total of 13,675 calibration points, combining natural-state and 1960-2006 exploitation data. The principal model parameters identified and estimated by inverse modeling include the fracture permeability and fracture porosity of the geothermal reservoir, the initial natural upflow rate, the base-layer porosity, and the permeabilities of the infiltration zones. Heat and mass balances derived from the calibrated model helped identify the sources of the geothermal reserves in the field. With the addition of five makeup wells, simulation forecasts for the 2007-2032 period predict a sustainable average steam production of 29 kg/s, which is sufficient to maintain the generation of 6.8 MWe at the Pauzhetsky power plant.
Date: April 1, 2008
Creator: Finsterle, Stefan; Kiryukhin, A.V.; Asaulova, N.P. & Finsterle, S.
Object Type: Article
System: The UNT Digital Library
Investigation of the Downwelling LW Differences Between the Niamey AMF Main and Supplementary Sites (open access)

Investigation of the Downwelling LW Differences Between the Niamey AMF Main and Supplementary Sites

The overall average downwelling longwave (LW) measured at the Niamey supplementary facility (S1) is 6-8 Wm-2 less than that measured by the two instruments located at the ARM Mobile Facility (AMF) main (N1) site. Examination of all other data available at both sites does not reveal any overarching differences that suggest this should be the case. However, examination of the pyrgeometer case and dome temperatures do suggest that the S1 values are also anomalously low, which in turn would explain the downwelling LW anomaly since the LW is calculated using these temperatures. Our recommendation then is to normalize the S1 data to the average N1 value by applying an adjustment factor to the S1 downwelling pyrgeometer case and dome temperatures (in Kelvin), then recalculating the downwelling LW values. The adjustment factor (0.00305) has been determined as that factor that brings the overall average S1 LWdn to agree with the overall average of the two N1 LWdn data series. We note that there is no reason to expect that the two site averages would actually be exactly equal to one another, and thus our recommendation is viewed as likely moving the S1 data in the right direction and by normalizing to …
Date: April 1, 2008
Creator: Long, CN; Gotseff, P & Dutton, EG
Object Type: Report
System: The UNT Digital Library
Issues in Benchmarking Human Reliability Analysis Methods: A Literature Review. (open access)

Issues in Benchmarking Human Reliability Analysis Methods: A Literature Review.

There is a diversity of human reliability analysis (HRA) methods available for use in assessing human performance within probabilistic risk assessment (PRA). Due to the significant differences in the methods, including the scope, approach, and underlying models, there is a need for an empirical comparison investigating the validity and reliability of the methods. To accomplish this empirical comparison, a benchmarking study is currently underway that compares HRA methods with each other and against operator performance in simulator studies. In order to account for as many effects as possible in the construction of this benchmarking study, a literature review was conducted, reviewing past benchmarking studies in the areas of psychology and risk assessment. A number of lessons learned through these studies are presented in order to aid in the design of future HRA benchmarking endeavors.
Date: April 1, 2008
Creator: Lois, Erasmia; Forester, John Alan; Tran, Tuan Q.; Hendrickson, Stacey M. Langfitt & Boring, Ronald L.
Object Type: Report
System: The UNT Digital Library
ITS Version 6 : the integrated TIGER series of coupled electron/photon Monte Carlo transport codes. (open access)

ITS Version 6 : the integrated TIGER series of coupled electron/photon Monte Carlo transport codes.

ITS is a powerful and user-friendly software package permitting state-of-the-art Monte Carlo solution of lineartime-independent coupled electron/photon radiation transport problems, with or without the presence of macroscopic electric and magnetic fields of arbitrary spatial dependence. Our goal has been to simultaneously maximize operational simplicity and physical accuracy. Through a set of preprocessor directives, the user selects one of the many ITS codes. The ease with which the makefile system is applied combines with an input scheme based on order-independent descriptive keywords that makes maximum use of defaults and internal error checking to provide experimentalists and theorists alike with a method for the routine but rigorous solution of sophisticated radiation transport problems. Physical rigor is provided by employing accurate cross sections, sampling distributions, and physical models for describing the production and transport of the electron/photon cascade from 1.0 GeV down to 1.0 keV. The availability of source code permits the more sophisticated user to tailor the codes to specific applications and to extend the capabilities of the codes to more complex applications. Version 6, the latest version of ITS, contains (1) improvements to the ITS 5.0 codes, and (2) conversion to Fortran 90. The general user friendliness of the software has …
Date: April 1, 2008
Creator: Franke, Brian Claude; Kensek, Ronald Patrick & Laub, Thomas William
Object Type: Report
System: The UNT Digital Library
JV Task 6 - Coal Ash Resources Research Consortium Research (open access)

JV Task 6 - Coal Ash Resources Research Consortium Research

The Coal Ash Resources Research Consortium{reg_sign} (CARRC{reg_sign}, pronounced 'cars') focuses on performing fundamental and applied scientific and engineering research emphasizing the environmentally safe, economical use of coal combustion by-products (CCBs). CARRC member organizations, which include utilities and marketers, are key to developing industry-driven research in the area of CCB utilization and ensuring its successful application. The U.S. Department of Energy is a partner in CARRC through the EERC Jointly Sponsored Research Program (JSRP), which provides matching funds for industrial member contributions and facilitates an increased level of effort in CARRC. CARRC tasks were designed to provide information on CCB performance, including environmental performance, engineering performance, favorable economics, and improved life cycle of products and projects. CARRC technical research tasks are developed based on member input and prioritization. CARRC special projects are developed with members and nonmembers to provide similar information and to support activities, including the assembly and interpretation of data, support for standards development and technology transfer, and facilitating product development and testing. CARRC activities from 1998 to 2007 included a range of research tasks, with primary work performed in laboratory tasks developed to answer specific questions or evaluate important fundamental properties of CCBs. CARRC topical reports were prepared …
Date: April 1, 2008
Creator: Pflughoeft-Hassett, Debra; Buckley, Tera; Dockter, Bruce; Eylands, Kurt; Hassett, David; Heebink, Loreal et al.
Object Type: Report
System: The UNT Digital Library
Kaolinite dissolution and precipitation kinetics at 22oC and pH 4 (open access)

Kaolinite dissolution and precipitation kinetics at 22oC and pH 4

Dissolution and precipitation rates of low defect Georgia kaolinite (KGa-1b) as a function of Gibbs free energy of reaction (or reaction affinity) were measured at 22 C and pH 4 in continuously stirred flowthrough reactors. Steady state dissolution experiments showed slightly incongruent dissolution, with a Si/Al ratio of about 1.12 that is attributed to the re-adsorption of Al on to the kaolinite surface. No inhibition of the kaolinite dissolution rate was apparent when dissolved aluminum was varied from 0 and 60 {micro}M. The relationship between dissolution rates and the reaction affinity can be described well by a Transition State Theory (TST) rate formulation with a Temkin coefficient of 2 R{sub diss} (mol/m{sup 2}s) = 1.15 x 10{sup -13} [1-exp(-{Delta}G/2RT)]. Stopping of flow in a close to equilibrium dissolution experiment yielded a solubility constant for kaolinite at 22 C of 10{sup 7.57}. Experiments on the precipitation kinetics of kaolinite showed a more complex behavior. One conducted using kaolinite seed that had previously undergone extensive dissolution under far from equilibrium conditions for 5 months showed a quasi-steady state precipitation rate for 105 hours that was compatible with the TST expression above. After this initial period, however, precipitation rates decreased by an order …
Date: April 1, 2008
Creator: Steefel, Carl; Yang, L. & Steefel, C.I.
Object Type: Article
System: The UNT Digital Library
Laboratory Directed Research and Development Program FY 2007 Annual Report (open access)

Laboratory Directed Research and Development Program FY 2007 Annual Report

The Oak Ridge National Laboratory (ORNL) Laboratory Directed Research and Development (LDRD) program reports its status to the U.S. Department of Energy (DOE) in March of each year. The program operates under the authority of DOE Order 413.2B, 'Laboratory Directed Research and Development' (April 19, 2006), which establishes DOE's requirements for the program while providing the Laboratory Director broad flexibility for program implementation. LDRD funds are obtained through a charge to all Laboratory programs. This report includes summaries for all ORNL LDRD research activities supported during FY 2007. The associated FY 2007 ORNL LDRD Self-Assessment (ORNL/PPA-2008/2) provides financial data and an internal evaluation of the program's management process. ORNL is a DOE multiprogram science, technology, and energy laboratory with distinctive capabilities in materials science and engineering, neutron science and technology, energy production and end-use technologies, biological and environmental science, and scientific computing. With these capabilities ORNL conducts basic and applied research and development (R&D) to support DOE's overarching mission to advance the national, economic, and energy security of the United States and promote scientific and technological innovation in support of that mission. As a national resource, the Laboratory also applies its capabilities and skills to specific needs of other federal …
Date: April 1, 2008
Creator: Sjoreen, Terrence P
Object Type: Report
System: The UNT Digital Library
Lean-Burn Stationary Natural Gas Reciprocating Engine Operation with a Prototype Miniature Diode Side Pumped Passively Q-switched Laser Spark Plug (open access)

Lean-Burn Stationary Natural Gas Reciprocating Engine Operation with a Prototype Miniature Diode Side Pumped Passively Q-switched Laser Spark Plug

To meet the ignition system needs of large bore lean burn stationary natural gas engines a laser diode side pumped passively Q-switched laser igniter was developed and used to ignite lean mixtures in a single cylinder research engine. The laser design was produced from previous work. The in-cylinder conditions and exhaust emissions produced by the miniaturized laser were compared to that produced by a laboratory scale commercial laser system used in prior engine testing. The miniaturized laser design as well as the combustion and emissions data for both laser systems was compared and discussed. It was determined that the two laser systems produced virtually identical combustion and emissions data.
Date: April 1, 2008
Creator: McIntyre, Dustin L.; Woodruff, Steven D.; McMillian, Michael H.; Richardson, Steven W. & Gautam, Mridul
Object Type: Article
System: The UNT Digital Library
Learning Demonstration Progress Report -- Spring 2008 (open access)

Learning Demonstration Progress Report -- Spring 2008

This report documents key results from DOE's Controlled Hydrogen Fleet and Infrastructure Validation and Demonstration Project based on data through December 2007.
Date: April 1, 2008
Creator: Wipke, K.; Sprik, S. & Kurtz, J.
Object Type: Report
System: The UNT Digital Library
Long Duration Testing of Type C Thermocouples at 1500 °C (open access)

Long Duration Testing of Type C Thermocouples at 1500 °C

Experience with Type C thermocouples operating for long periods in the 1400 to 1600 °C temperature range indicate that significant decalibration occurs, often leading to expensive downtime and material waste. As part of an effort to understand the mechanisms causing drift in these thermocouples, the Idaho National Laboratory conducted a long duration test at 1500 °C containing eight Type C thermocouples. As report in this document, results from this long duration test were adversely affected due to oxygen ingress. Nevertheless, results provide key insights about the impact of precipitate formation on thermoelectric response. Post-test examinations indicate that thermocouple signal was not adversely impacted by the precipitates detected after 1,000 hours of heating at 1,500 °C and suggest that the signal would not have been adversely impacted by these precipitates for longer durations (if oxygen ingress had not occurred in this test).
Date: April 1, 2008
Creator: Rempe, Joy L.; Knudson, Darrell L.; Daw, J. E. & Wilkins, S. C.
Object Type: Report
System: The UNT Digital Library
Luminosity measurements at hadron colliders (open access)

Luminosity measurements at hadron colliders

In this paper we discuss luminosity measurements at Tevatron and HERA as well as plans for luminosity measurements at LHC. We discuss luminosity measurements using the luminosity detectors of the experiments as well as measurements by the machine. We address uncertainties of the measurements, challenges and lessons learned.
Date: April 1, 2008
Creator: Papadimitriou, Vaia
Object Type: Article
System: The UNT Digital Library

M&C (Measurements & Characterization) PDIL Integrated and Stand-Alone Tools

None
Date: April 1, 2008
Creator: Sheldon, P.
Object Type: Presentation
System: The UNT Digital Library
Materials Degradation in Light Water Reactors: Life After 60,??? (open access)

Materials Degradation in Light Water Reactors: Life After 60,???

Nuclear reactors present a very harsh environment for components service. Components within a reactor core must tolerate high temperature water, stress, vibration, and an intense neutron field. Degradation of materials in this environment can lead to reduced performance, and in some cases, sudden failure. A recent EPRI-led study interviewed 47 US nuclear utility executives to gauge perspectives on long-term operation of nuclear reactors. Nearly 90% indicated that extensions of reactor lifetimes to beyond 60 years were likely. When polled on the most challenging issues facing further life extension, two-thirds cited plant reliability as the key issue with materials aging and cable/piping as the top concerns for plant reliability. Materials degradation within a nuclear power plant is very complex. There are many different types of materials within the reactor itself: over 25 different metal alloys can be found with can be found within the primary and secondary systems, not to mention the concrete containment vessel, instrumentation and control, and other support facilities. When this diverse set of materials is placed in the complex and harsh environment coupled with load, degradation over an extended life is indeed quite complicated. To address this issue, the USNRC has developed a Progressive Materials Degradation Approach …
Date: April 1, 2008
Creator: Busby, Jeremy T.; Nanstad, Randy K.; Stoller, Roger E.; Feng, Zhili & Naus, Dan J.
Object Type: Report
System: The UNT Digital Library
Measurement of Inclusive Jet Cross Sections in Z/gamma*(->e+e-) + jets Production in ppbar Collisions at s**(1/2) = 1.96 TeV with the CDF Detector (open access)

Measurement of Inclusive Jet Cross Sections in Z/gamma*(->e+e-) + jets Production in ppbar Collisions at s**(1/2) = 1.96 TeV with the CDF Detector

This Ph.D. thesis presents the measurement of inclusive jet cross sections in Z/{gamma}* {yields} e{sup +}e{sup -} events using 1.7 fb{sup -1} of data collected by the upgraded CDF detector during the Run II of the Tevatron. The Midpoint cone algorithm is used to search for jets in the events after identifying the presence of a Z/{gamma}* boson through the reconstruction of its decay products. The measurements are compared to next-to-LO (NLO) pQCD predictions for events with one and two jets in the final state. The perturbative predictions are corrected for the contributions of non-perturbative processes, like the underlying event and the fragmentation of the partons into jets of hadrons. These processes are not described by perturbation theory and must be estimated from phenomenological models. In this thesis, a number of measurements are performed to test different models of underlying event and hadronization implemented in LO plus parton shower Monte Carlo generator programs. Chapter 2 is devoted to the description of the theory of strong interactions and jet phenomenology at hadron colliders. Chapter 3 contains the description of the Tevatron collider and the CDF detector. The analysis is described in detail in Chapter 4. Chapter 5 shows the measurement of …
Date: April 1, 2008
Creator: Salto Bauza, Oriol
Object Type: Thesis or Dissertation
System: The UNT Digital Library