Monthly newsletter discussing news and activities related to the Atmospheric Radiation Measurement Program, articles about weather and atmospheric phenomena, and other related topics.

The CDF experiment has performed several measurements in the area of beauty and charm physics with the data collected during the Run I of the Tevatron. The experiment is now ready to collect new data at higher luminosity with a substantially improved detector. We discuss these improvements and the future measurements in this area of physics accessible after the first few years of data taking. These include the measurement of the mixing frequency of B{sub s} mesons and that of CP violation effects in the B{sub 0} sector.

A ''Holy Grail'' of NDE research is a non-destructive method for measuring fatigue damage prior to crack initiation. High-Tc scanning SQUID microscopy may be a useful tool. Because of the exceptional magnetic sensitivity of this technique, fatigue damage can be detected well before microcrack initiation, and in the absence of other obvious microstructure or property changes. Given the spatial resolution of the technique, undamaged material can be located and used to set internal standards.

Poor control of steam generator water level of a nuclear power plant may lead to frequent nuclear reactor shutdowns. These shutdowns are more common at low power where the plant exhibits strong non-minimum phase characteristics and flow measurements at low power are unreliable in many instances. There is need to investigate this problem and systematically design a controller for water level regulation. This work is concerned with the study and the design of a suitable controller for a U-Tube Steam Generator (UTSG) of a Pressurized Water Reactor (PWR) which has time varying dynamics. The controller should be suitable for the water level control of UTSG without manual operation from start-up to full load transient condition. Some preliminary simulation results are presented that demonstrate the effectiveness of the proposed controller. The development of the complete control algorithm includes components such as robust output tracking, and adaptively estimating both the system parameters and state variables simultaneously. At the present time all these components are not completed due to time constraints. A robust tracking component of the controller for water level control is developed and its effectiveness on the parameter variations is demonstrated in this study. The results appear encouraging and they are …

A chapter report issued by the General Accounting Office with an abstract that begins "The narrow margin of victory in the 2000 presidential election aroused concern about the reliability of voting machines; the training of polling place workers; and the extent to which local jurisdictions accepted ballots from members of the military, their dependents, or citizens living abroad. The Federal Voting Assistance program developed several useful tools for voters and Voting Assistance Officers, but many potential voters GAO spoke to were unaware of them. Some installations did not meet the Department of Defense (DOD) and service requirements because they provided insufficient numbers of trained Voting Assistance Officers, voter training, and voting materials. Overseas citizens and federal employees said that the State Department provided useful information. However, many military and overseas voters believe that challenges remain, such as understanding and complying with state requirements and local procedures for absentee voting. Security and privacy issues also present challenges to widespread use of the Internet for voting. Information on the precise number of military and overseas absentee votes that local jurisdictions disqualified nationwide in the 2000 general election and the reasons for disqualification are not readily available. However, GAO's national telephone survey found …

This brochure talks about Renewable Energy development in China. Advancing world energy security by helping China develop more diversified energy resources and mitigating environmental damage through deployment of renewable energy and energy efficiency measures.

A new period of data taking started on March 2001 for both collaborations CDF and D0. In 2 years around 2 fb{sup -1} of data should be collected by both experiments with a huge number of events containing B mesons available to perform many kinds of measurements. In this paper we discuss our expectations for a few of these measurements. These expectations rely on the experience gained by analyzing the Run I data whenever it is possible and on Monte Carlo otherwise.

Other written product issued by the General Accounting Office with an abstract that begins "This is an insert to GAO's publication, Serving the Congress and the Nation, describing the agency mission, work environment, and career opportunities at GAO."

Other written product issued by the General Accounting Office with an abstract that begins "This is an insert to GAO's publication, Serving the Congress and the Nation, describing the role, functions, and responsibilities of GAO's Professional Development Program team."

Other written product issued by the General Accounting Office with an abstract that begins "This is an insert to GAO's publication, Serving the Congress and the Nation, describing the goals, functions, and responsibilities of GAO's Strategic Plan framework."

Monte Carlo (MCNP4B) and Discrete Ordinates (DORT) calculations were carried out to estimate {sup 60}Co and {sup 152}Eu activation as a function of ground range due to neutrons emitted from the Hiroshima A-bomb. Results of ORNL DORT and MCNP calculations using RZ cylindrical air-over-ground models are compared with LANL MCNP results obtained with an XYZ air-over-ground model. All of the calculations were carried out using ENDF/B-VI cross-section data and detailed angle and energy resolved neutron emission spectra from the weapon. Favorable agreement was achieved for the {sup 60}Co and {sup 152}Eu activation for ground ranges out to 1000m from the three calculations.

This paper highlights future developments in the field of in-situ transmission electron microscopy, as applied specifically to the issues of deformation in thin films and nanostructured materials. Emphasis is place on the forthcoming technical advances that will aid in extraction of improved quantitative experimental data using this technique.

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Recent advances in micro-electro-mechanical systems (MEMS) have led to the development of uncooled infrared detectors operate as micromechanical thermal detectors or micromechanical quantum detectors. The authors report on a new method for photon detection using electronic (photo-induced) stresses in semiconductor microstructures. Photo-induced stress in semiconductor microstructures, is caused by changes in the charge carrier density in the conduction band and photon detection results from the measurement of the photo-induced bending of semiconductor microstructures. Small changes in position (displacement) of microstructures are routinely measured in atomic force microscopy (AFM) where atomic imaging of surfaces relies on the measurement of small changes (< 10{sup -9} m) in the bending of microcantilevers. Changes in the conduction band charge carrier density can result either from direct photo-generation of free charge carriers (electrons, holes) or from photoelectrons emitted from thin metal film surfaces in contact with a semiconductor microstructure which forms a Schottky barrier. In their studies, they investigated three systems: (1) Si microstructures, (2)InSb microstructures and (3) Si microstructures coated with a thin film of Pt. They found that for Si the photo-induced stress results in a contraction of the crystal lattice due to the presence of excess electron-hole-pairs while for InSb photo-induced stress …

The benefits of energy and operational cost savings from using copper rotors are well recognized. The main barrier to die casting copper rotors is short mold life. This paper introduces a new approach for manufacturing copper-bar rotors. Either copper, aluminum, or their alloys can be used for the end rings. Both solid-core and laminated-core rotors were built. High quality joints of aluminum to copper were produced and evaluated. This technology can also be used for manufacturing aluminum bar rotors with aluminum end rings. Further development is needed to study the life time reliability of the joint, to optimize manufacturing fixtures, and to conduct large-rotor tests.

There exists a need to develop novel, advanced, unattended magnetic and chemical micro-sensor systems for successful detection, localization, classification and tracking of ground time critical targets of interest. Consistent with the underlying long-term objectives of the development of unattended ground sensors (UGS) program they have investigated the use of a new planted ground sensor platform based on Micro-Electro-Mechanical Systems (MEMS) that can offer magnetic, chemical and possibly acoustic detection. The envisioned micro-system will be low-power and low-cost and will be built around a single type of microstructure element integrating a monolithic optical system and electronics package. This micro sensor can also incorporate burst telemetry to transmit the information, a renewable power source and will be capable of operating under field conditions, with sufficient sensitivity to permit high detection rates, and with sufficient chemical selectivity to prevent high false alarm rates. Preliminary studies, initial designs, and key predicted performance parameters will be presented. Possible applications of such a system include sensitive perimeter monitoring such as minefields and military/nuclear bases, vehicle detection, and aircraft navigation systems, and drug enforcement operations. The results of the present work demonstrate that the microcalorimetric spectroscopy technique can be applied to detect and identify chemicals in the …

It is well understood that the stability of axial diffusion flames is dependent on the mixing behavior of the fuel and combustion air streams. Combustion aerodynamic texts typically describe flame stability and transitions from laminar diffusion flames to fully developed turbulent flames as a function of increasing jet velocity. Turbulent diffusion flame stability is greatly influenced by recirculation eddies that transport hot combustion gases back to the burner nozzle. This recirculation enhances mixing and heats the incoming gas streams. Models describing these recirculation eddies utilize conservation of momentum and mass assumptions. Increasing the mass flow rate of either fuel or combustion air increases both the jet velocity and momentum for a fixed burner configuration. Thus, differentiating between gas velocity and momentum is important when evaluating flame stability under various operating conditions. The research efforts described herein are part of an ongoing project directed at evaluating the effect of flame aerodynamics on NO{sub x} emissions from coal fired burners in a systematic manner. This research includes both experimental and modeling efforts being performed at the University of Arizona in collaboration with Purdue University. The objective of this effort is to develop rational design tools for optimizing low NO{sub x} burners. Experimental …

The radiation environment aboard the space shuttle and the International Space Station includes high-Z and high-energy (HZE) particles that are part of the galactic cosmic radiation (GCR) spectrum. Iron-56 is considered to be one of the most biologically important parts of the GCR spectrum. Tissue-equivalent proportional counters (TEPC) are used as active dosimeters on manned space flights. These TEPC's are further used to determine average quality factor for each space mission. A TEPC simulating a 1 micron diameter sphere of tissue was exposed as part of a particle spectrometer to iron-56 at energies from 200-1000 MeV/nucleon. The response of TEPC in terms of frequency-averaged lineal energy, dose-averaged lineal energy, as well as energy deposited at different impact parameters through detector was determined for six different incident energies of iron-56 in this energy range. Calculations determined that charged particle equilibrium was achieved for each of the six experiments. Energy depositions at different impact parameters were calculated using a radial dose distribution model and the results compared to experimental data.

Several publications during the last 10 years by Woodward and colleagues have: (1) indicated a theory based on special relativity, that predicted transient mass fluctuations; (2) cited specific embodiments where a net average force would be present; (3) suggested a few ways that this theory might be tested in the laboratory; and (4) reported such test results incorporating these embodiments, which are interpreted to support theory (1) to (3) above. In this paper we show that: (1) the average force predicted by Woodward's theory occurred only because of a neglected term in a product derivative, and that when the neglected term is correctly returned, the average force identically vanishes; (2) this vanishment of the average force occurs for arbitrary forcing functions, not just the sinusoidal one considered by Woodward; (3) the transient mass fluctuation, predicted by Woodward, was developed in a theory which neglected local gravitational forces which are several dozen orders of magnitude greater; (4) additionally considering the dominant local gravitational forces produces a vastly smaller transient mass fluctuation; (5) several inconsistencies between Woodward's referents and the development of his wave equation lead to a formulation that does not follow from the antecedents even in the absence of the …

Presently the Heavy Ion Fusion Virtual National Laboratory is researching ion sources and injector concepts to understand how to optimize beam brightness over a range of currents (50-2000 mA argon equivalent). One concept initially accelerates millimeter size, milliamp beamlets to 1 MeV before merging them into centimeter size, ampere beams. Computer simulations have shown the final brightness of the merged beams is dominated by the emittance growth of the merging process, as long as the beamlets ion temperature is below a few eV. Thus, a RF multicusp source capable of high current density can produce beams with better brightness compared to ones extracted from a colder source with a large aperture and lower current density. As such, experiments have begun to develop a RF multicusp source capable of delivering one amp of extracted beam current. It is expected that it will require 10 kW of 13 MHz RF power delivered via a quartz shielded, one and half turn, four inch diameter antenna. Important considerations in the development of the source include the dependence of current density and beam ion temperature on consumed RF power and gas pressure. A fast rise time ({approx} 100 ns) for the extracted beam pulse must …

A purely hadronic simulation is performed of the recently reported data from PHOBOS at energies of {radical}s = 56, 130 GeV using the relativistic heavy ion cascade LUCIFER which had previously given a good description of the NA49 inclusive spectra at {radical}s = 17.2 GeV/A. The results compare well with these early measurements at RHIC and indeed successfully predict the increase in multiplicity now seen by PHOBOS and the other RHIC detectors at the nominal maximum energy of {radical}s = 200 GeV/A, suggesting that evidence for quark-gluon matter remains elusive.

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Newsletter of the Texas Department of Health discussing the news, activities, and events of the organization and other information related to health in Texas.

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