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Economic and Other Implications of Switching from Coal to Natural Gas at the Capitol Power Plant and at Electricity-Generating Units Nationwide (open access)

Economic and Other Implications of Switching from Coal to Natural Gas at the Capitol Power Plant and at Electricity-Generating Units Nationwide

Correspondence issued by the Government Accountability Office with an abstract that begins "Elevated concentrations of greenhouse gases--carbon dioxide, methane, nitrous oxide, and several synthetic chemicals--in the atmosphere resulting from the combustion of fossil fuels and other sources have the potential to cause significant changes in the earth's climate. These potential impacts include shifts in sea level and weather patterns and could pose threats to coastal and other infrastructure. Concerns about the potential impacts of climate change have led the Congress to consider legislation that would place binding, nationwide limits on greenhouse gas emissions, and the House of Representatives' leadership has initiated efforts to decrease emissions attributable to its operations. Nearly all of the greenhouse gas emissions from House operations consist of carbon dioxide and are associated with electricity purchased from utilities and the combustion of fossil fuels in the Capitol Power Plant (CPP), which provides steam and chilled water for heating and cooling the Capitol building and 23 surrounding facilities. The Architect of the Capitol (AOC) operates CPP. In June 2007, the Chief Administrative Officer (CAO) of the House of Representatives released the Green the Capitol initiative (the initiative) at the direction of the Speaker and the Majority Leader. Among …
Date: May 1, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
U.S. Capitol Police: Status of Efforts to Address Prior GAO Recommendations on Administrative and Management Operations (open access)

U.S. Capitol Police: Status of Efforts to Address Prior GAO Recommendations on Administrative and Management Operations

Testimony issued by the Government Accountability Office with an abstract that begins "The United States Capitol Police (USCP) is responsible for securing the 276-acre Capitol Complex, including protecting Members of Congress, visitors, and congressional facilities. In response to heightened security concerns, various requests, and legislative mandates over the years, GAO has reported on management control problems in five key areas: (1) establishing an accountability framework for monitoring recommendations, (2) establishing a risk management framework, (3) ensuring financial management, (4) ensuring strategic and human capital planning, and (5) managing information technology (IT). From January 2004 through March 2007, GAO made 46 recommendations aimed at improving USCP administrative and management operations and achieving strategic goals. This testimony reports on the status of USCP's efforts to address GAO's recommendations. To conduct its work, GAO analyzed USCP documentation, such as risk matrices, budget documents, and strategic plans. GAO also conducted interviews with USCP officials and contractors on their efforts related to its recommendations. GAO performed this work from October 2007 through April 2008. USCP generally agreed with GAO's 46 prior recommendations and GAO's assessment of the status of USCP's efforts to implement those recommendations. Along these lines, USCP needs to complete those actions in …
Date: May 1, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Higher Education: Multiple Higher Education Tax Incentives Create Opportunities for Taxpayers to Make Costly Mistakes (open access)

Higher Education: Multiple Higher Education Tax Incentives Create Opportunities for Taxpayers to Make Costly Mistakes

Testimony issued by the Government Accountability Office with an abstract that begins "Federal assistance helps students and families pay for postsecondary education through several policy tools--grant and loan programs authorized by Title IV of the Higher Education Act of 1965 and more recently enacted tax preferences. This testimony summarizes our 2005 report and provides updates on (1) how Title IV assistance compares to that provided through the tax code (2) the extent to which tax filers effectively use education tax preferences, (3) potential benefits and costs of simplifying federal student aid, and (4) what is known about the effectiveness of federal assistance. This hearing is an opportunity to consider whether changes should be made in the government's overall strategy for providing such assistance or to the individual programs and tax provisions that provide the assistance. This statement is based on updates to previously published GAO work and reviews of relevant literature."
Date: May 1, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Defense Infrastructure: Planning Efforts for the Proposed Military Buildup on Guam Are in Their Initial Stages, with Many Challenges Yet to Be Addressed (open access)

Defense Infrastructure: Planning Efforts for the Proposed Military Buildup on Guam Are in Their Initial Stages, with Many Challenges Yet to Be Addressed

Testimony issued by the Government Accountability Office with an abstract that begins "To reduce the burden of the U.S. military presence on Japanese communities while maintaining a continuing presence of U.S. forces in the region, in 2005 and 2006 the U.S.-Japan Defense Policy Review Initiative outlined the effort to relocate American military units in Japan to other areas, including Guam. The Department of Defense (DOD) plans to move 8,000 Marines and an estimated 9,000 dependents from Okinawa, Japan, to Guam by the 2014 goal. GAO was asked to discuss the planning effort for the buildup of U.S. forces and facilities on Guam. Accordingly, this testimony addresses (1) DOD's planning process for the military buildup on Guam, (2) potential challenges for DOD and the government of Guam associated with the buildup, and (3) the status of planning efforts by the government of Guam to meet infrastructure challenges caused by the buildup. This testimony is based largely on findings of a September 2007 GAO report on DOD's overseas master plans and prior work on issues related to the U.S. military presence in Okinawa. It is also based, in part, on preliminary observations from an ongoing GAO review of DOD's planning effort to …
Date: May 1, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library

Optimizing Carbon Nanotube Contacts For Use In Organic Photovoltaics

None
Date: May 1, 2008
Creator: Barnes, T.; Blackburn, J.; Tenent, R.; Morfa, A.; Heben, M. & Coutts, T.
Object Type: Presentation
System: The UNT Digital Library
High Penetration, Grid Connected Photovoltaic Technology Codes and Standards: Preprint (open access)

High Penetration, Grid Connected Photovoltaic Technology Codes and Standards: Preprint

This paper reports the interim status in identifying and reviewing photovoltaic (PV) codes and standards (C&S) and related electrical activities for grid-connected, high-penetration PV systems with a focus on U.S. electric utility distribution grid interconnection.
Date: May 1, 2008
Creator: Basso, T. S.
Object Type: Article
System: The UNT Digital Library
Use of microphysical relationships to discern growth/decay mechanisms of cloud droplets with focus on Z-LWC relationships. (open access)

Use of microphysical relationships to discern growth/decay mechanisms of cloud droplets with focus on Z-LWC relationships.

Cloud droplet size distributions hence the key microphysical quantities (e.g., radar reflectivity, droplet concentration, liquid water content, relative dispersion, and mean-volume radius) are determined by different physical mechanisms, including pre-cloud aerosols as CCNs, cloud updraft, and various turbulent entrainment-mixing processes. Therefore, different relationships among these microphysical properties are expected in response to these various mechanisms. The effect of turbulent entrainment-mixing processes is particularly vexing, with different entrainment-mixing processes likely leading to different microphysical relationships. Cloud radar has been widely used to infer the cloud liquid water content (L) from the measurement of radar reflectivity (Z) using a Z-L relationship. Existing Z-L expressions have been often obtained empirically, and differ substantially (Khain et al. 2008). The discrepancy among Z-L relations, which has been hindering the application of cloud radar in measuring cloud properties, likely stems from the different relationships between the relevant microphysical properties caused by different physical processes. This study first analyzes the Z-L relationship theoretically, and identify the key microphysical properties that affect this relationship, and then address the effects of various processes on the Z-L relationship by discerning the characteristics of the relationships between the relative dispersion, droplet concentration, liquid water content, and mean-volume radius calculated from in-situ …
Date: May 1, 2008
Creator: Liu, Y.; Daum, P. H.; Yum, S. S. & Wang, J.
Object Type: Article
System: The UNT Digital Library

Accelerated UV Test Methods for Encapsulants of Photovoltaic Modules

None
Date: May 1, 2008
Creator: Kempe, M. D.
Object Type: Presentation
System: The UNT Digital Library
ACRF Instrumentation Status: New, Current, and Future - May 2008 (open access)

ACRF Instrumentation Status: New, Current, and Future - May 2008

The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following five sections: (1) new instrumentation in the process of being acquired and deployed, (2) field campaigns, (3) existing instrumentation and progress on improvements or upgrades, (4) proposed future instrumentation, and (5) Small Business Innovation Research instrument development.
Date: May 1, 2008
Creator: Voyles, J. W.
Object Type: Report
System: The UNT Digital Library
Where do fossil fuel carbon dioxide emissions from California go? An analysis based on radiocarbon observations and an atmospheric transport model (open access)

Where do fossil fuel carbon dioxide emissions from California go? An analysis based on radiocarbon observations and an atmospheric transport model

Characterizing flow patterns and mixing of fossil fuel-derived CO{sub 2} is important for effectively using atmospheric measurements to constrain emissions inventories. Here we used measurements and a model of atmospheric radiocarbon ({sup 14}C) to investigate the distribution and fluxes of atmospheric fossil fuel CO{sub 2} across the state of California. We sampled {sup 14}C in annual C{sub 3} grasses at 128 sites and used these measurements to test a regional model that simulated anthropogenic and ecosystem CO{sub 2} fluxes, transport in the atmosphere, and the resulting {sup 14}C of annual grasses ({Delta}{sub g}). Average measured {Delta}{sub g} in Los Angeles, San Francisco, the Central Valley, and the North Coast were 27.7 {+-} 20.0, 44.0 {+-} 10.9, 48.7 {+-} 1.9, and 59.9 {+-} 2.5{per_thousand}, respectively, during the 2004-2005 growing season. Model predictions reproduced regional patterns reasonably well, with estimates of 27.6 {+-} 2.4, 39.4 {+-} 3.9, 46.8 {+-} 3.0, and 59.3 {+-} 0.2{per_thousand} for these same regions and corresponding to fossil fuel CO{sub 2} mixing ratios (Cf) of 13.7, 6.1, 4.8, and 0.3 ppm. {Delta}{sub g} spatial heterogeneity in Los Angeles and San Francisco was higher in the measurements than in the predictions, probably from insufficient spatial resolution in the fossil …
Date: May 1, 2008
Creator: Riley, W. J.; Hsueh, D. Y.; Randerson, J. T.; Fischer, M. L.; Hatch, J. G.; Pataki, D. E. et al.
Object Type: Article
System: The UNT Digital Library

Intrinsic DX Centers in Ternary Chalcopyrite Semiconductors

The conclusions of this report are: (1) intrinsic donor-type defects In{sub Cu}, Ga{sub Cu}, and V{sub Se}, and their complexes with V{sub Cu} cause metastability, but also act to limit V{sub OC}; (2) growth conditions which minimize these defects (Cu-rich/Se-rich) are very different from those currently used; and (3) overcoming V{sub OC} limitation requires to address other issues and trade-offs.
Date: May 1, 2008
Creator: Lany, S. & Zunger, A.
Object Type: Presentation
System: The UNT Digital Library
Help for the Developers of Control System Cyber Security Standards (open access)

Help for the Developers of Control System Cyber Security Standards

A Catalog of Control Systems Security: Recommendations for Standards Developers (Catalog), aimed at assisting organizations to facilitate the development and implementation of control system cyber security standards, has been developed. This catalog contains requirements that can help protect control systems from cyber attacks and can be applied to the Critical Infrastructures and Key Resources of the United States and other nations. The requirements contained in the catalog are a compilation of practices or various industry bodies used to increase the security of control systems from both physical and cyber attacks. They should be viewed as a collection of recommendations to be considered and judiciously employed, as appropriate, when reviewing and developing cyber security standards for control systems. The recommendations in the Catalog are intended to be broad enough to provide any industry using control systems the flexibility needed to develop sound cyber security standards specific to their individual security requirements.
Date: May 1, 2008
Creator: Evans, Robert P.
Object Type: Article
System: The UNT Digital Library
Silicon Solar Cells with Front Hetero-contact and Aluminum Alloy Back Junction (Poster) (open access)

Silicon Solar Cells with Front Hetero-contact and Aluminum Alloy Back Junction (Poster)

The objectives of this report are: (1) to apply industrial back Al process in efficient n-wafer cells with a-Si:H front surface passivation; and (2) to evaluate the surface recombination velocity (SRV) of the a-Si:H passivated front surface with different surface preparation procedures.
Date: May 1, 2008
Creator: Yuan, H.-C.; Page, M. R.; Iwaniczko, E.; Xu, Y.; Roybal, L.; Wang, Q. et al.
Object Type: Article
System: The UNT Digital Library
RHIC RF Harmonic Numbers for Low Energy Operations (open access)

RHIC RF Harmonic Numbers for Low Energy Operations

There have been several test runs of RHIC operations to explore the feasibility of luminosity production at low energies. There is considerable international interest in the possible existence of a QCD phase diagram critical point in the RHIC gold-gold collision energy range of {radical}s{sub NN} = 5-50 GeV[l, 2, 3]. This paper reviews the RF harmonic number constraints for RHIC gold-gold collisions in this energy range, and concludes that optimal simultaneous collisions at both experiments are only feasible when the harmonic number is divisible by 9.
Date: May 1, 2008
Creator: Satogata, T.
Object Type: Report
System: The UNT Digital Library
U.S. Department of Energy Wind and Hydropower Technologies: Top 10 Program Accomplishments (open access)

U.S. Department of Energy Wind and Hydropower Technologies: Top 10 Program Accomplishments

This brochure describes the top ten accompishments of the DOE Wind Energy Program during the past 30 years.
Date: May 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Effects of Temporal Wind Patterns on the Value of Wind-Generated Electricity in California and the Northwest (open access)

Effects of Temporal Wind Patterns on the Value of Wind-Generated Electricity in California and the Northwest

Wind power production is variable, but also has diurnal and seasonal patterns. These patterns differ between sites, potentially making electric power from some wind sites more valuable for meeting customer loads or selling in wholesale power markets. This paper investigates whether the timing of wind significantly affects the value of electricity from sites in California and the Northwestern United States. We use both measured and modeled wind data and estimate the time-varying value of wind power with both financial and load-based metrics. We find that the potential difference in wholesale market value between better-correlated and poorly correlated wind sites is modest, on the order of 5-10 percent. A load-based metric, power production during the top 10 percent of peak load hours, varies more strongly between sites, suggesting that the capacity value of different wind projects could vary by as much as 50 percent based on the timing of wind alone.
Date: May 1, 2008
Creator: Wiser, Ryan H; Wiser, Ryan H & Fripp, Matthias
Object Type: Article
System: The UNT Digital Library

Design of Shallow p-type Dopants in ZnO

ZnO is a promising material for short wave-length opto-electronic devices such as UV lasers and LEDs due to its large exciton binding energy and low material cost. ZnO can be doped easily n-type, but the realization of stable p-type ZnO is rather difficult. Using first-principles band structure methods the authors address what causes the p-type doping difficulty in ZnO and how to overcome the p-type doping difficulty in ZnO.
Date: May 1, 2008
Creator: Wei, S.H.; Li, J. & Y., Yan.
Object Type: Presentation
System: The UNT Digital Library
Corrective Action Decision Document/Closure Report for Corrective Action Unit 234: Mud Pits, Cellars, and Mud Spills Nevada Test Site, Nevada, Revision 0 (open access)

Corrective Action Decision Document/Closure Report for Corrective Action Unit 234: Mud Pits, Cellars, and Mud Spills Nevada Test Site, Nevada, Revision 0

This Corrective Action Decision Document/Closure Report has been prepared for Corrective Action Unit (CAU) 234, Mud Pits, Cellars, and Mud Spills, located in Areas 2, 3, 4, 12, and 15 at the Nevada Test Site, Nevada, in accordance with the Federal Facility Agreement and Consent Order (FFACO, 1996; as amended February 2008). Corrective Action Unit 234 is comprised of the following 12 corrective action sites: •02-09-48, Area 2 Mud Plant #1 •02-09-49, Area 2 Mud Plant #2 •02-99-05, Mud Spill •03-09-02, Mud Dump Trenches •04-44-02, Mud Spill •04-99-02, Mud Spill •12-09-01, Mud Pit •12-09-04, Mud Pit •12-09-08, Mud Pit •12-30-14, Cellar •12-99-07, Mud Dump •15-09-01, Mud Pit The purpose of this Corrective Action Decision Document/Closure Report is to provide justification and documentation supporting the recommendation for closure of CAU 234 with no further corrective action. To achieve this, corrective action investigation (CAI) activities were performed as set forth in the Corrective Action Investigation Plan for Corrective Action Unit 234: Mud Pits, Cellars, and Mud Spills (NNSA/NSO, 2007). The purpose of the CAI was to fulfill the following data needs as defined during the data quality objective (DQO) process: •Determine whether contaminants of concern are present. •If contaminants of concern are …
Date: May 1, 2008
Creator: Evenson, Grant
Object Type: Report
System: The UNT Digital Library
Observation of Disappearance of Muon Neutrinos in the NuMI Beam (open access)

Observation of Disappearance of Muon Neutrinos in the NuMI Beam

The Main Injector Neutrino Oscillation Search (MINOS) is a two detector long-baseline neutrino experiment designed to study the disappearance of muon neutrinos. MINOS will test the {nu}{sub {mu}} {yields} {nu}{sub {tau}} oscillation hypothesis and measure precisely {Delta}m{sub 23}{sup 2} and sin{sup 2} 2{theta}{sub 23} oscillation parameters. The source of neutrinos for MINOS experiment is Fermilab's Neutrinos at the Main Injector (NuMI) beamline. The energy spectrum and the composition of the beam is measured at two locations, one close to the source and the other 735 km down-stream in the Soudan Mine Underground Laboratory in northern Minnesota. The precision measurement of the oscillation parameters requires an accurate prediction of the neutrino flux at the Far Detector. This thesis discusses the calculation of the neutrino flux at the Far Detector and its uncertainties. A technique that uses the Near Detector data to constrain the uncertainties in the calculation of the flux is described. The data corresponding to an exposure of 2.5 x 10{sup 20} protons on the NuMI target is presented and an energy dependent disappearance pattern predicted by neutrino oscillation hypotheses is observed in the Far Detector data. The fit to MINOS data, for given exposure, yields the best fit values …
Date: May 1, 2008
Creator: Pavlovic, Zarko
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Search for Low Mass SM Higgs at the Tevatron (open access)

Search for Low Mass SM Higgs at the Tevatron

None
Date: May 1, 2008
Creator: Sanders, Michiel P.
Object Type: Article
System: The UNT Digital Library

Stability of CIS/CIGS Modules at the Outdoor Test Facility Over Two Decades

None
Date: May 1, 2008
Creator: Del Cueto, J. A.
Object Type: Presentation
System: The UNT Digital Library
Search for the Flavor Changing Neutral Current Decay t $\to Zq$ in $p \bar{p}$ Collisions at $\sqrt{s}=1.96$ (open access)

Search for the Flavor Changing Neutral Current Decay t $\to Zq$ in $p \bar{p}$ Collisions at $\sqrt{s}=1.96$

We report a search for the flavor changing neutral current (FCNC) decay of the top quark t {yields} Zq (q = u, c) in p{bar p} collisions at {radical}s = 1.96 TeV using a data sample corresponding to an integrated luminosity of 1.9 fb{sup -1} collected by the CDF II detector. This decay is strongly suppressed in the standard model (SM) and a signal at the Tevatron would be an indication of physics beyond the SM. Using Z+ {ge} 4 jet final state candidate events, both with and without an identified bottom quark jet, we discriminate signal from background by exploring kinematic constraints present in FCNC events and obtain an upper limit of {Beta}(t {yields} Zq) < 3.7% at 95% C.L.
Date: May 1, 2008
Creator: Aaltonen, : T.
Object Type: Article
System: The UNT Digital Library
Radiation damage due to electromagnetic showers (open access)

Radiation damage due to electromagnetic showers

Radiation-induced damage due to atomic displacements is essential to correctly predict the behavior of materials in nuclear reactors and at charged-particle accelerators. Traditionally the damage due to hadrons was of major interest. The recent increased interest in high-energy lepton colliders gave rise to the problem of prediction of radiation damage due to electromagnetic showers in a wide energy range--from a few hundred keV and up to a few hundred GeV. The report describes results of an electron- and positron-induced displacement cross section evaluation. It is based on detailed lepton-nucleus cross sections, realistic nuclear form-factors and a modified Kinchin-Pease damage model. Numerical data on displacement cross sections for various target nuclei is presented.
Date: May 1, 2008
Creator: Rakhno, Igor; Mokhov, Nikolai & Striganov, Sergei
Object Type: Report
System: The UNT Digital Library
Modeling Microbunching from Shot Noise Using Vlasov Solvers (open access)

Modeling Microbunching from Shot Noise Using Vlasov Solvers

Unlike macroparticle simulations, which are sensitive to unphysical statistical fluctuations when the number of macroparticles is smaller than the bunch population, direct methods for solving the Vlasov equation are free from sampling noise and are ideally suited for studying microbunching instabilities evolving from shot noise. We review a 2D (longitudinal dynamics) Vlasov solver we have recently developed to study the microbunching instability in the beam delivery systems for x-ray FELs and present an application to FERMI{at}Elettra. We discuss, in particular, the impact of the spreader design on microbunching.
Date: May 1, 2008
Creator: Venturini, Marco; Venturini, Marco & Zholents, Alexander
Object Type: Article
System: The UNT Digital Library