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Transatlantic Regulatory Cooperation: Background and Analysis
This report is intended to serve as an introduction and primer on a complicated, broad, and often highly technical set of issues. It is presented in seven parts: the first section describes the nature and scope of U.S.-EU regulatory barriers; the second section explains the rationale for regulatory cooperation; the third section highlights the differences in U.S.-EU regulatory approaches; the fourth section examines the various forms of regulatory cooperation; the fifth section evaluates the results of past initiatives at regulatory cooperation; the sixth section analyses the creation and operation of the Transatlantic Economic Council; and the last section highlights the role of Congress in transatlantic regulatory cooperation.
Date:
October 22, 2008
Creator:
Ahearn, Raymond J.
Object Type:
Report
System:
The UNT Digital Library
U.S.-European Union Trade Relations: Issues and Policy Challenges
None
Date:
October 24, 2002
Creator:
Ahearn, Raymond J.
Object Type:
Report
System:
The UNT Digital Library
In Vivo Characterization of Human APOA5 Haplotypes
Increased plasma triglycerides concentrations are an independent risk factor for cardiovascular disease. Numerous studies support a reproducible genetic association between two minor haplotypes in the human apolipoprotein A5 gene (APOA5) and increased plasma triglyceride concentrations. We thus sought to investigate the effect of these minor haplotypes (APOA5*2 and APOA5*3) on ApoAV plasma levels through the precise insertion of single-copy intact APOA5 haplotypes at a targeted location in the mouse genome. While we found no difference in the amount of human plasma ApoAV in mice containing the common APOA5*1 and minor APOA5*2 haplotype, the introduction of the single APOA5*3 defining allele (19W) resulted in 3-fold lower ApoAV plasma levels consistent with existing genetic association studies. These results indicate that S19W polymorphism is likely to be functional and explain the strong association of this variant with plasma triglycerides supporting the value of sensitive in vivo assays to define the functional nature of human haplotypes.
Date:
October 1, 2006
Creator:
Ahituv, Nadav; Akiyama, Jennifer; Chapman-Helleboid, Audrey; Fruchart, Jamila & Pennacchio, Len A.
Object Type:
Article
System:
The UNT Digital Library
Realizing the Opportunities of Neutron Cross Section Measurements at RIA
The Rare Isotope Accelerator will produce many isotopes at never before seen rates. This will allow for the first time measurements on isotopes very far from stability and new measurement opportunities for unstable nuclei near stability. In fact, the production rates are such that it should be possible to collect 10 micrograms of many isotopes with a half-life of 1 day or more. This ability to make targets of short-lived nuclei enables the possibility of making neutron cross-section measurements important to the astrophysics and the stockpile stewardship communities. But to fully realize this opportunity, the appropriate infrastructure must be included at the RIA facility. This includes isotope harvesting capabilities, radiochemical areas for processing collected material, and an intense, ''mono-energetic'', tunable neutron source. As such, we have been developing a design for neutron source facility to be included at the RIA site. This facility would produce neutrons via intense beams of deuterons and protons on a variety of targets. The facility would also include the necessary radiochemical facilities for target processing. These infrastructure needs will be discussed in addition to the methods that would be employed at RIA for measuring these neutron cross-sections.
Date:
October 13, 2004
Creator:
Ahle, L; Hausmann, M; Reifarth, R; Roberts, K; Roeben, M; Rusnak, B et al.
Object Type:
Article
System:
The UNT Digital Library
Unsaturated Zone Flow Patterns and Analysis
This Analysis/Model Report (AMR) documents the development of an expected-case model for unsaturated zone (UZ) flow and transport that will be described in terms of the representativeness of models of the natural system. The expected-case model will provide an evaluation of the effectiveness of the natural barriers, assess the impact of conservatism in the Total System Performance Assessment (TSPA), and support the development of further models and analyses for public confidence building. The present models used in ''Total System Performance Assessment for the Site Recommendation'' (Civilian Radioactive Waste Management System Management and Operating Contractor (CRWMS M&O) 2000 [1532461]) underestimate the natural-barrier performance because of conservative assumptions and parameters and do not adequately address uncertainty and alternative models. The development of an expected case model for the UZ natural barrier addresses issues regarding flow-pattern analysis and modeling that had previously been treated conservatively. This is in line with the Repository Safety Strategy (RSS) philosophy of treating conservatively those aspects of the UZ flow and transport system that are not important for achieving regulatory dose (CRWMS M&O 2000 [153246], Section 1.1.1). The development of an expected case model for the UZ also provides defense-in-depth in areas requiring further analysis of uncertainty and …
Date:
October 17, 2001
Creator:
Ahlers, C.
Object Type:
Report
System:
The UNT Digital Library
Advanced Computational Model for Three-Phase Slurry Reactors Progress Report: October 2001
In the second year of the project, the Eulerian-Lagrangian formulation for analyzing three-phase slurry flows in a bubble column is further developed. The approach uses an Eulerian analysis of liquid flows in the bubble column, and makes use of the Lagrangian trajectory analysis for the bubbles and particle motions. An experimental set for studying a two-dimensional bubble column is also developed. The operation of the bubble column is being tested and diagnostic methodology for quantitative measurements is being developed. An Eulerian computational model for the flow condition in the two-dimensional bubble column is also being developed. The liquid and bubble motions are being analyzed and the results are being compared with the experimental setup. Solid-fluid mixture flows in ducts and passages at different angle of orientations were analyzed. The model predictions were compared with the experimental data and good agreement was found. Gravity chute flows of solid-liquid mixtures is also being studied. Further progress was also made in developing a thermodynamically consistent model for multiphase slurry flows with and without chemical reaction in a state of turbulent motion. The balance laws are obtained and the constitutive laws are being developed. Progress was also made in measuring concentration and velocity of …
Date:
October 1, 2001
Creator:
Ahmadi, Goodarz
Object Type:
Report
System:
The UNT Digital Library
Advanced Computational Model for Three-Phase Slurry Reactors Progress Report: October 2004
In this project, an Eulerian-Lagrangian formulation for analyzing three-phase slurry flows in a bubble column was developed. The approach used an Eulerian analysis of liquid flows in the bubble column, and made use of the Lagrangian trajectory analysis for the bubbles and particle motions. The bubble-bubble and particle-particle collisions are included the model. The model predictions are compared with the experimental data and good agreement was found An experimental setup for studying two-dimensional bubble columns was developed. The multiphase flow conditions in the bubble column were measured using optical image processing and Particle Image Velocimetry techniques (PIV). A simple shear flow device for bubble motion in a constant shear flow field was also developed. The flow conditions in simple shear flow device were studied using PIV method. Concentration and velocity of particles of different sizes near a wall in a duct flow was also measured. The technique of Phase-Doppler anemometry was used in these studies. An Eulerian volume of fluid (VOF) computational model for the flow condition in the two-dimensional bubble column was also developed. The liquid and bubble motions were analyzed and the results were compared with observed flow patterns in the experimental setup. Solid-fluid mixture flows in ducts …
Date:
October 1, 2004
Creator:
Ahmadi, Goodarz
Object Type:
Report
System:
The UNT Digital Library
Measurement of Recombination Parameters of Photovoltaic Materials by Resonant-Coupled Photoconductive Decay: Preprint
Presented at the 2001 NCPV Program Review Meeting: Novel contactless measurement technique that provides minority carrier lifetime, ambipolar mobility, and diffusion length.
Date:
October 1, 2001
Creator:
Ahrenkiel, R. & Johnston, S.
Object Type:
Article
System:
The UNT Digital Library
Application of a Device for Uniform Web Drying and Preheating Using Microwave Energy
The project summarized in this report dealt with an evaluation of new microwave applicator ideas for paper preheating and drying. The technical basis for success in this project is the fact that Industrial Microwave Systems has recently identified certain previously unrecognized wave guide ''design variables'' and hardware implementation concepts that can be employed to greatly improve the uniformity of microwave energy distribution for continuous flow processes. Two applicator concepts were ultimately evaluated, a Cross-Machine Direction (CD) oriented applicator and a Machine Direction (MD) oriented applicator. The economic basis for success is the result of several factors. Since 1985, the capital expenditure required for an industrial microwave applicator system has decreased by a factor of four. The maintenance costs have decreased by a factor of 10 and the life expectancy of the magnetron has increased by more than a factor of four to in excess of 8,000 hours (nearly one year at 24 hours/day operation).
Date:
October 2, 2003
Creator:
Ahrens, Frederick W.; Habeger, C.; Loughran, J. & Patterson, T.
Object Type:
Report
System:
The UNT Digital Library
Booster Fault Study No. 16: Deuteron Beam on the B6 Dump
A report on the booster fault study carried out on January 22, 2003.
Date:
October 2003
Creator:
Ahrens, L. A.; Brown, K. A. & Gardner, C. J.
Object Type:
Report
System:
The UNT Digital Library
InGaP/GaAs/Ge Multi-Junction Solar Cell Efficiency Improvements Using Epitaxial Germanium
None
Date:
October 17, 2000
Creator:
Aiken, Daniel James
Object Type:
Article
System:
The UNT Digital Library
The Evolution of Swift/BAT blazars and the origin of the MeV background
We use 3 years of data from the Swift/BAT survey to select a complete sample of X-ray blazars above 15 keV. This sample comprises 26 Flat-Spectrum Radio Quasars (FSRQs) and 12 BL Lac objects detected over a redshift range of 0.03 < z < 4.0. We use this sample to determine, for the first time in the 15-55 keV band, the evolution of blazars. We find that, contrary to the Seyfert-like AGNs detected by BAT, the population of blazars shows strong positive evolution. This evolution is comparable to the evolution of luminous optical QSOs and luminous X-ray selected AGNs. We also find evidence for an epoch-dependence of the evolution as determined previously for radio-quiet AGNs. We interpret both these findings as a strong link between accretion and jet activity. In our sample, the FSRQs evolve strongly, while our best-fit shows that BL Lacs might not evolve at all. The blazar population accounts for 10-20% (depending on the evolution of the BL Lacs) of the Cosmic X-ray background (CXB) in the 15-55 keV band. We find that FSRQs can explain the entire CXB emission for energies above 500 keV solving the mystery of the generation of the MeV background. The evolution …
Date:
October 17, 2009
Creator:
Ajello, M.; /SLAC /KIPAC, Menlo Park; Costamante, L.; /Stanford U., HEPL /KIPAC, Menlo Park; Sambruna, R.M.; Gehrels, N. et al.
Object Type:
Article
System:
The UNT Digital Library
Optimal experiment design for time-lapse traveltime tomography
Geophysical monitoring techniques offer the only noninvasive approach capable of assessing both the spatial and temporal dynamics of subsurface fluid processes. Increasingly, permanent sensor arrays in boreholes and on the ocean floor are being deployed to improve the repeatability and increase the temporal sampling of monitoring surveys. Because permanent arrays require a large up-front capital investment and are difficult (or impossible) to re-configure once installed, a premium is placed on selecting a geometry capable of imaging the desired target at minimum cost. We present a simple approach to optimizing downhole sensor configurations for monitoring experiments making use of differential seismic traveltimes. In our case, we use a design quality metric based on the accuracy of tomographic reconstructions for a suite of imaging targets. By not requiring an explicit singular value decomposition of the forward operator, evaluation of this objective function scales to problems with a large number of unknowns. We also restrict the design problem by recasting the array geometry into a low dimensional form more suitable for optimization at a reasonable computational cost. We test two search algorithms on the design problem: the Nelder-Mead downhill simplex method and the Multilevel Coordinate Search algorithm. The algorithm is tested for four …
Date:
October 1, 2009
Creator:
Ajo-Franklin, J.B.
Object Type:
Article
System:
The UNT Digital Library
Characterizing the fabric of the urban environment: A case studyof Metropolitan Chicago, Illinois and Executive Summary
Urban fabric data are needed in order to estimate the impactof light-colored surfaces (roofs and pavements) and urban vegetation(trees, grass, shrubs) on the meteorology and air quality of a city, andto design effective implementation programs. In this report, we discussthe result of a semi-automatic Monte-Carlo statistical approach used todevelop data on surface-type distribution and city-fabric makeup(percentage of various surface-types) using aerial colororthophotography. The digital aerial photographs for metropolitan Chicagocovered a total of about 36 km2 (14 mi2). At 0.3m resolution, there wereapproximately 3.9 x 108 pixels of data. Four major land-use types wereexamined: commercial, industrial, residential, andtransportation/communication. On average, for the areas studied, atground level vegetation covers about 29 percent of the area (ranging 4 80percent); roofs cover about 25 percent (ranging 8 41 percent), and pavedsurfaces about 33 percent (ranging 12 59 percent). For the most part,trees shade streets, parking lots, grass, and side-walks. In commercialareas, paved surfaces cover 50 60 percent of the area. In residentialareas, on average, paved surfaces cover about 27percent of the area.Land-use/land-cover (LULC) data from the United States Geological Surveywas used to extrapolate these results from neighborhood scales tometropolitan Chicago. In an area of roughly 2500 km2, defining most ofmetropolitan Chicago, over 53 percent …
Date:
October 30, 2001
Creator:
Akbari, Hashem & Rose, Leanna Shea
Object Type:
Report
System:
The UNT Digital Library
Feasibility Study of Using Short Wave Infrared Cavity Ringdown Spectroscopy (SWIR-CRDS) for Biological Agent Detection
This project focused on determining the feasibility of using short wave infrared (SWIR) cavity ring down spectroscopy (CRDS) as a means for real-time detection of biological aerosols. The first part of the project involved identifying biological agent signatures that could be detected with SWIR CRDS. After an exhaustive search of the open literature it was determined that whole biological spores and/or cells would not be good candidates for direct SWIR CRDS probing because they have no unique SWIR signatures. It was postulated that while whole cells or spores are not good candidates for SWIR CRDS detection, their pyrolysis break-down products might be. A literature search was then conducted to find biological pyrolysis products with low molecular weights and high symmetry since these species most likely would have overtone and combination vibrational bands that can be detected in the SWIR. It was determined that pyrrole, pyridine and picolinamide were good candidates for evaluation. These molecules are formed when proteins and porphyrins, proteins and dipicolinic acid, and dipicolinic acid are pyrolyzed, respectively. The second part of the project involved measuring quantitative SWIR spectra of pyrrole, pyridine and picolinamide in PNNL’s FTIR Spectroscopy Laboratory. Spectral information about these molecules, in the vapor phase …
Date:
October 1, 2007
Creator:
Aker, Pam M.; Johnson, Timothy J.; Williams, Richard M. & Valentine, Nancy B.
Object Type:
Report
System:
The UNT Digital Library
Industrial Applications of Induced Positron Annihilation
This presentation discusses industrial applications of induced positron annihilation.
Date:
October 6, 2004
Creator:
Akers, D.
Object Type:
Presentation
System:
The UNT Digital Library
Current Research in Wireless at UNT
This presentation discusses wireless networks, access point selections, traffic balancing, multi-cell CDMA, user distribution modeling, and call admission control.
Date:
October 2004
Creator:
Akl, Robert G.
Object Type:
Presentation
System:
The UNT Digital Library
Quantification of Absorption, Retention and Elimination of Two Different Oral Doses of Vitamin a in Zambian Boys Using Accelerator Mass Spectrometry
A recent survey indicated that high-dose vitamin A supplements (HD-VAS) had no apparent effect on vitamin A (VA) status of Zambian children <5 y of age. To explore possible reasons for the lack of response to HD-VAS among Zambian children, we quantified the absorption, retention, and urinary elimination of either a single HDVAS (60 mg) or a smaller dose of stable isotope (SI)-labeled VA (5 mg), which was used to estimate VA pool size, in 3-4 y old Zambian boys (n = 4 for each VA dose). A 25 nCi tracer dose of [{sup 14}C{sub 2}]-labeled VA was co-administered with the HD-VAS or SI-labeled VA, and 24-hr stool and urine samples were collected for 3 and 7 consecutive days, respectively, and 24-hr urine samples at 4 later time points. Accelerator Mass Spectrometry (AMS) was used to measure the cumulative excretion of {sup 14}C in stool and urine 3d after dosing to estimate, respectively, absorption and retention of the VAS and SI-labeled VA. The urinary elimination rate (UER) was estimated by plotting {sup 14}C in urine vs. time, and fitting an exponential equation to the data. Estimates of mean absorption, retention and the UER were 83.8 {+-} 7.1%, 76.3 {+-} 6.7%, …
Date:
October 12, 2009
Creator:
Aklamati, E. K.; Mulenga, M.; Dueker, S. R.; Buchholz, B. A.; Peerson, J. M.; Kafwembe, E. et al.
Object Type:
Article
System:
The UNT Digital Library
Fast Ignition Experimental and Theoretical Studies
We are becoming dependent on energy more today than we were a century ago, and with increasing world population and booming economies, sooner or later our energy sources will be exhausted. Moreover, our economy and welfare strongly depends on foreign oil and in the shadow of political uncertainties, there is an urgent need for a reliable, safe, and cheap energy source. Thermonuclear fusion, if achieved, is that source of energy which not only will satisfy our demand for today but also for centuries to come. Today, there are two major approaches to achieve fusion: magnetic confinement fusion (MFE) and inertial confinement fusion (ICF). This dissertation explores the inertial confinement fusion using the fast ignition concept. Unlike the conventional approach where the same laser is used for compression and ignition, in fast ignition separate laser beams are used. This dissertation addresses three very important topics to fast ignition inertial confinement fusion. These are laser-to-electron coupling efficiency, laser-generated electron beam transport, and the associated isochoric heating. First, an integrated fast ignition experiment is carried out with 0.9 kJ of energy in the compression beam and 70 J in the ignition beam. Measurements of absolute K{sub {alpha}} yield from the imploded core revealed …
Date:
October 20, 2006
Creator:
Akli, K
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Hot Electron Generation and Transport Using K(alpha) Emission
We have conducted experiments on both the Vulcan and Titan laser facilities to study hot electron generation and transport in the context of fast ignition. Cu wires attached to Al cones were used to investigate the effect on coupling efficiency of plasma surround and the pre-formed plasma inside the cone. We found that with thin cones 15% of laser energy is coupled to the 40{micro}m diameter wire emulating a 40{micro}m fast ignition spot. Thick cone walls, simulating plasma in fast ignition, reduce coupling by x4. An increase of prepulse level inside the cone by a factor of 50 reduces coupling by a factor of 3.
Date:
October 15, 2009
Creator:
Akli, K. U.; Stephens, R. B.; Key, M. H.; Bartal, T.; Beg, F. N.; Chawla, S. et al.
Object Type:
Article
System:
The UNT Digital Library
LCLS LLRF Upgrades to the SLAC Linac
The Linac Coherent Light Source (LCLS) at SLAC will be the brightest X-ray laser in the world when it comes on line. In order to achieve the brightness a 200fS length electron bunch is passed through an undulator. To create the 200fS, 3kA bunch, a 10pS electron bunch, created from a photo cathode in an RF gun, is run off crest on the RF to set up a position to energy correlation. The bunch is then compressed by chicanes. The stability of the RF system is critical in setting up the position to energy correlation. Specifications derived from simulations require the RF system to be stable to below 200fS in several critical injector stations and the last kilometer of linac. The SLAC linac RF system is being upgraded to meet these requirements.
Date:
October 4, 2007
Creator:
Akre, R.; Dowell, D.; Emma, P.; Frisch, J.; Hong, B.; Kotturi, K. et al.
Object Type:
Article
System:
The UNT Digital Library
Development of a Novel Catalyst for NO Decomposition
Air pollution arising from the emission of nitrogen oxides as a result of combustion taking place in boilers, furnaces and engines, has increasingly been recognized as a problem. New methods to remove NO{sub x} emissions significantly and economically must be developed. The current technology for post-combustion removal of NO is the selective catalytic reduction (SCR) of NO by ammonia or possibly by a hydrocarbon such as methane. The catalytic decomposition of NO to give N{sub 2} will be preferable to the SCR process because it will eliminate the costs and operating problems associated with the use of an external reducing species. The most promising decomposition catalysts are transition metal (especially copper)-exchanged zeolites, perovskites, and noble metals supported on metal oxides such as alumina, silica, and ceria. The main shortcoming of the noble metal reducible oxide (NMRO) catalysts is that they are prone to deactivation by oxygen. It has been reported that catalysts containing tin oxide show oxygen adsorption behavior that may involve hydroxyl groups attached to the tin oxide. This is different than that observed with other noble metal-metal oxide combinations, which have the oxygen adsorbing on the noble metal and subsequently spilling over to the metal oxide. This observation …
Date:
October 22, 2004
Creator:
Akyurtlu, Ates & Akyurtlu, Jale F.
Object Type:
Report
System:
The UNT Digital Library
Comparison of Experimental and Model Data for the Evaporation of a Synthetic Topopah Spring Tuff Pore Water, Yucca Mountain, NV
The evaporation of a range of synthetic pore water solutions representative of the potential high-level-nuclear-waste repository at Yucca Mountain, NV is being investigated. The motivation of this work is to understand and predict the range of brine compositions that may contact the waste containers from evaporation of pore waters, because these brines could form corrosive thin films on the containers and impact their long-term integrity. A relatively complex synthetic Topopah Spring Tuff pore water was progressively concentrated by evaporation in a closed vessel, heated to 95 C in a series of sequential experiments. Periodic samples of the evaporating solution were taken to determine the evolving water chemistry. According to chemical divide theory at 25 C and 95 C our starting solution should evolve towards a high pH carbonate brine. Results at 95 C show that this solution evolves towards a complex brine that contains about 99 mol% Na{sup +} for the cations, and 71 mol% Cl{sup -}, 18 mol% {Sigma}CO{sub 2}(aq), 9 mol% SO{sub 4}{sup 2-} for the anions. Initial modeling of the evaporating solution indicates precipitation of aragonite, halite, silica, sulfate and fluoride phases. The experiments have been used to benchmark the use of the EQ3/6 geochemical code in …
Date:
October 14, 2003
Creator:
Alai, M; Sutton, M & Carroll, S
Object Type:
Article
System:
The UNT Digital Library
Probing Dissolution Surface Structure in Phosphate Glasses Using 1H-31 Cross-Polarization Edited Radio Frequency Dipolar Recoupling Experiments
None
Date:
October 2, 2000
Creator:
Alam, T.M. & Lang, D.P.
Object Type:
Article
System:
The UNT Digital Library