People with serious cardiac problems have had their life span extended with the development of the prosthetic heart valve. However, the valves operate continuously at approximately 39 million cycles per year and are therefore subject to structural failures either by faulty design or material fatigue. The development of a non-invasive technique using an acoustic contact microphone and sophisticated signal processing techniques has been proposed and demonstrated on limited data sets. In this paper we discuss an extension of the techniques to perform the heart valve tests in an anechoic like. Here the objective is to extract a ''pure'' sound or equivalently the acoustical vibration response of the prosthetic valves in a quiet environment. The goal is to demonstrate that there clearly exist differences between values which have a specific mechanical defect known as single leg separation (SLS) and non-defective valves known as intact (INT). We discuss the signal processing and results of anechoic acoustic measurements on 50 prosthetic valves in the tank. Finally, we show the results of the individual runs for each valve, point out any of the meaningful features that could be used to distinguish the SLS from INT and summarize the experiments.

This paper presents a gesture recognition system for visualization navigation. Scientists are interested in developing interactive settings for exploring large data sets in an intuitive environment. The input consists of registered 3-D data. A geometric method using Bezier curves is used for the trajectory analysis and classification of gestures. The hand gesture speed is incorporated into the algorithm to enable correct recognition from trajectories with variations in hand speed. The method is robust and reliable: correct hand identification rate is 99.9% (from 1641 frames), modes of hand movements are correct 95.6% of the time, recognition rate (given the right mode) is 97.9%. An application to gesture-controlled visualization of 3D bioinformatics data is also presented.

With the number of small, inexpensive Unmanned Air Vehicles (UAVs) increasing, it is feasible to build multi-UAV sensing networks. In particular, by using UAVs in conjunction with unattended ground sensors, a degree of persistent sensing can be achieved. With proper UAV cooperation algorithms, sensing is maintained even though exceptional events, e.g., the loss of a UAV, have occurred. In this paper a cooperation technique that allows multiple UAVs to perform coordinated, persistent sensing with unattended ground sensors over a wide area is described. The technique automatically adapts the UAV paths so that on the average, the amount of time that any sensor has to wait for a UAV revisit is minimized. We also describe the Simulation, Tactical Operations and Mission Planning (STOMP) software architecture. This architecture is designed to help simulate and operate distributed sensor networks where multiple UAVs are used to collect data.

Laboratory experiments on wave propagation through saturated and partially saturated porous media have often been conducted on porous cylinders that were initially fully saturated and then allowed to dry while continuing to acquire data on the wave behavior. Since it is known that drying typically progresses from the outside to the inside, a sensible physical model of this process is concentric cylinders having different saturation levels--the simplest example being a fully dry outer cylindrical shell together with a fully wet inner cylinder. We use this model to formulate the equations for wave dispersion in porous cylinders for patchy saturation (i.e., drainage) conditions. In addition to multiple modes of propagation obtained numerically from these dispersion relations, we find two distinct analytical expressions for torsional wave modes.

An effort has been started to measure the short pulse laser absorption and energy partition at relativistic laser intensities up to 10{sup 21} W/cm{sup 2}. Plasma polarization spectroscopy is expected to play an important role in determining fast electron generation and measuring the electron distribution function.

The Pacific Northwest National Laboratory numerically modeled flow conditions upstream of the regulating outlets at Dworshak Dam, North Fork Clearwater River, Idaho. Simulations were performed using the computational fluid dynamics model Flow-3D, a peer reviewed and validated three-dimensional Reynolds-averaged Navier-Stokes hydrodynamic model. Results were studied to determine the impacts of water surface elevation and discharge though the three regulating outlets on flow velocities in the reservoir forebay. These simulations were in general support of a larger research program conducted by the Idaho Department of Fish and Game that is evaluating the efficacy of strobe lights to deter fish from entering the regulating outlets and powerhouse turbine intakes. Simulation results indicate that large variations in forebay water velocities occur over the typical range of regulating outlet operations and seasonal water surface fluctuations. As expected, water velocities generally increase with larger outlet gate openings and higher water surface elevations. Simulations span typical regulating outlet operations: forebay water surface elevations between 1460 ft and 1600 ft and regulating outlet gate valve openings between 1 ft and 10 ft open. In addition, simulations examined flow conditions when only one or two of the three regulating outlets were operating. The resulting matrix of 24 unique …

The Laser Science and Technology (LS&T) Program Annual Report 2001 provides documentation of the achievements of the LLNL LS&T Program during the April 2001 to March 2002 period using three formats: (1) an Overview that is a narrative summary of important results for the year; (2) brief summaries of research and development activity highlights within the four Program elements: Advanced Lasers and Components (AL&C), Laser Optics and Materials (LO&M), Short Pulse Laser Applications and Technologies (SPLAT), and High-Energy Laser System and Tests (HELST); and (3) a compilation of selected articles and technical reports published in reputable scientific or technology journals in this period. All three elements (Annual Overview, Activity Highlights, and Technical Reports) are also on the Web: http://laser.llnl.gov/lasers/pubs/icfq.html. The underlying mission for the LS&T Program is to develop advanced lasers, optics, and materials technologies and applications to solve problems and create new capabilities of importance to the Laboratory and the nation. This mission statement has been our guide for defining work appropriate for our Program. A major new focus of LS&T beginning this past year has been the development of high peak power short-pulse capability for the National Ignition Facility (NIF). LS&T is committed to this activity.

Accelerator Mass Spectrometry (AMs) was used to investigate the relative contribution to diesel engine particulate matter (PM) from the ethanol and diesel fractions of blended fuels. Four test fuel blends and a control diesel fuel baseline were investigated. The test fuels were comprised of {sup 14}C depleted diesel fuel mixed with contemporary grain ethanol ({approx}400 the {sup 14}C concentration of diesel). An emulsifier (Span 85) or cosolvent (butyl alcohol) was used to facilitate mixing. The experimental test engine was a 1993 Cummins B5.9 diesel rated at 175 hp at 2500 rpm. Test fuels were run at steady-state conditions of 1600 rpm and 210 ft-lbs, and PM samples were collected on quartz filters following dilution of engine exhaust in a mini-dilution tunnel. AMs analysis of the filter samples showed that the ethanol contributed less to PM relative to its fraction in the fuel blend. For the emulsified blends, 6.4% and 10.3% contributions to PM were observed for 11.5% and 23.0% ethanol fuels, respectively. For the cosolvent blends, even lower contributions were observed (3.8% and 6.3% contributions to PM for 12.5% and 25.0.% ethanol fuels, respectively). The distribution of the oxygen, not just the quantity, was an important factor in reducing PM …

A study is performed to elucidate the chemical kinetic mechanism of combustion of toluene. A detailed chemical kinetic mechanism for toluene was improved by adding a more accurate description of the phenyl + O{sub 2} reaction channels. Results of the chemical kinetic mechanism are compared with experimental data obtained from premixed and nonpremixed systems. Under premixed conditions, predicted ignition delay times are compared with new experimental data obtained in shock tube. Also, calculated species concentration histories are compared to experimental flow reactor data from the literature. Critical conditions of extinction and ignition were measured in strained laminar flows under nonpremixed conditions in the counterflow configuration. Numerical calculations are performed using the chemical kinetic mechanism at conditions corresponding to those in the experiments. Critical conditions of extinction and ignition are predicted and compared with the experimental data. For both premixed and nonpremixed systems, sensitivity analysis was used to identify the reaction rate constants that control the overall rate of oxidation in each of the systems considered.

We compare the Implicit Monte Carlo (IMC) technique to the Symbolic IMC (SIMC) technique, with and without weight vectors in frequency space, for time-dependent line transport in the presence of collisional pumping. We examine the efficiency and accuracy of the IMC and SIMC methods for examples involving the evolution of a collisionally pumped trapping problem to steady-state, the surface heating of cold media by a beam, and the diffusion of energy from a localized region that is collisionally pumped. The importance of spatial biasing and teleportation for problems involving high opacity is demonstrated. Our numerical solution, along with its associated teleportation error, is checked against theoretical calculations for the last example.

Radioactive waste is scheduled to be retrieved from Hanford double-shell tanks AN-103, AN-104, AN-105 and AW-101 to the vitrification plant beginning about 2009. Retrieval may involve decanting the supernatant liquid and/or mixing the waste with jet pumps. In these four tanks, which contain relatively large volumes of retained gas, both of these operations are expected to induce buoyant displacement gas releases that can potentially raise the tank headspace hydrogen concentration to very near the lower flammability limit. This report describes the theory and detailed physical models for both the supernate decant and jet mixing processes and presents the results from applying the models to these operations in the four tanks. The technical bases for input parameter distributions are elucidated.

The primary objectives of this project are to assess, and improve our understanding of: (1) The effectiveness of various strategies to intentionally store carbon in the ocean through fertilization of the surface ocean with iron and/or macronutrients; and (2) Unanticipated environmental consequences of these ocean fertilization strategies. We propose to use what may be the best global ocean biogeochemical model in the world (PISCES) and apply it to perform the most realistic global-scale simulations of various iron fertilization scenarios. Versions of PISCES are currently used by MPI in Germany and IPSL in France. The model represents diatoms, coccolithophorids, and two classes of zooplankton. This model considers Fey N, P, O{sub 2}, Si, alkalinity, and carbon; for some of these it considers dissolved inorganic and organic, as well as particulate, forms. We would install the PISCES model with a minimum of modification into the LLNL ocean model, and perform an initial suite of simulations of both iron fertilization experiments (e.g., SOFeX) and proposed iron fertilization strategies. Based on the simulated experiments, we will analyze model deficiencies with respect to the observations and use this analysis to improve future versions of the model. The source code for and results from this set …

Potential leak detection, monitoring, and mitigation techniques are being developed to support Hanford single-shell tank waste retrieval operations. In July and August 2001, Pacific Northwest National Laboratory demonstrated several of these technologies for CH2M HILL Hanford Group, Inc., at the Mock Tank Site in the 200 East Area. These subsurface air flow and extraction (SAFE) technologies use air injection and extraction wells to create an advective air flowfield beneath a tank. SAFE includes the following technologies: 1) leak detection--in-tank tracers, flowfield disturbance, radon displacement, and tank waste vapors; 2) leak monitoring--partitioning tracer method and reactive tracers; 3) leak mitigation--soil desiccation before and after leakage and in situ gaseous reduction; and 4) subsurface characterization--interfacial tracers. This report provides an overview of these technologies and discusses the FY 2001 demonstration activities at the Mock Tank Site, their results, and implications for future work.

Millions of gallons of radioactive waste are stored in large underground tanks at DOE sites. The waste is made up of settled solids, in sludge form, at the bottom of the tank and a layer of supernatant liquid on top of it. It is necessary to mix the solids in the sludge layer with the supernatant liquid to facilitate their removal from the storage tanks for remediation. Our goal is to improve the mobilization of the settled solids by optimizing mixing with the supernatant liquid and preserving the mobility of the solids. This report investigates whether time-phase separation between pump head oscillations affects overall sludge mobilization. If a mixing jet from one pump happens to follow temporarily the path of the lead mixing jet, it may be possible to prevent or slow down the resettling of the heavy solid particles, maintaining them in suspension. If a retrieval pump were operating at the same time, it could facilitate removal of such particles. Preliminary experiments were carried out to observe whether time-phase separation has some influence on the overall mobilization. A brief account is presented of the successful mobilization and removal of most of the radioactive waste from Tank D8-2 at the …

The conversion of synthesis gas to hydrocarbons or alcohols involves highly exothermic reactions. Temperature control is a critical issue in these reactors for a number of reasons. Runaway reactions can be a serious safety issue, even raising the possibility of an explosion. Catalyst deactivation rates tend to increase with temperature, particularly of there are hot spots in the reactor. For alcohol synthesis, temperature control is essential because it has a large effect on the selectivity of the catalysts toward desired products. For example, for molybdenum disulfide catalysts unwanted side products such as methane, ethane, and propane are produced in much greater quantities if the temperature increases outside an ideal range. Slurry reactors are widely regarded as an efficient design for these reactions. In a slurry reactor a solid catalyst is suspended in an inert hydrocarbon liquid, synthesis gas is sparged into the bottom of the reactor, un-reacted synthesis gas and light boiling range products are removed as a gas stream, and heavy boiling range products are removed as a liquid stream. This configuration has several positive effects for synthesis gas reactions including: essentially isothermal operation, small catalyst particles to reduce heat and mass transfer effects, capability to remove heat rapidly …

Multi-modality imaging has an increasing role in the diagnosis and treatment of a large number of diseases, particularly if both functional and anatomical information are acquired and accurately co-registered. Hence, there is a resulting need for multi modality phantoms in order to validate image co-registration and calibrate the imaging systems. We present our PET-ultrasound phantom development, including PET and ultrasound images of a simple prostate phantom. We use agar and gelatin mixed with a radioactive solution. We also present our development of custom multi-modality phantoms that are compatible with PET, transrectal ultrasound (TRUS), MRI and CT imaging. We describe both our selection of tissue mimicking materials and phantom construction procedures. These custom PET-TRUS-CT-MRI prostate phantoms use agargelatin radioactive mixtures with additional contrast agents and preservatives. We show multi-modality images of these custom prostate phantoms, as well as discuss phantom construction alternatives. Although we are currently focused on prostate imaging, this phantom development is applicable to many multi-modality imaging applications.

Interactions between plasmas and their surrounding materials (plasma facing components) are of great interest to present and future magnetic fusion experiments, and ITER [ITER Physics Basis Editors, ITER Physics Exper Group Chairs, ITER Joint Central Team, and Physics Inte gration Unit, Nucl. Fusion 39, 2137 (1999)] in particular. This interest is the result of concerns with the survivability of these materials, as well as the impact of these interactions back on the plasma. These interactions begin on the surface, but can have consequences a few microns into the material.This mini-conference on these "first microns" was designed to bring to the Division of Plasma Physics Meeting experts on these topics who would otherwise not attend. At the same time, the mini-conference was intended to expose the broader fusion community to these issues. The mini-conference covered in three, half-day sessions the topics of lithium coatings and surfaces, mixed materials characteristics, and issues associated with graphite.

We present the search for the lepton flavour violating decay {tau} {yields} lK{sup 0}{sub s} with the BaBar experiment data. This process and many other lepton flavour violating {tau} decays, like {tau} {yields} {mu}{gamma} and {tau} {yields} lll, are one of the most promising channel to search for evidence of new physics. According to the Standard Model and the neutrino mixing parameters, branching fractions are estimated well below 10{sup -14}, but many models of new physics allow for branching fractions values close to the present experimental sensitivity. This analysis is based on a data sample of 469fb{sup -1} collected by BABAR detector at the PEP-II storage ring from 1999 to 2007, equivalent to 431 millions of {tau} pairs. the BABAR experiment, initially designed for studying CP violation in B mesons, has demonstrated to be one of the most suitable environments for studying {tau} decays. The tracking system, the calorimeter and the particle identification of BABAR, together with the knowledge of the {tau} initial energy, allow an extremely powerful rejection of background events that, for this analysis, is better than 10{sup -9}. Being {tau} {yields} lK{sup 0}{sub s} a decay mode without neutrinos, the signal {tau} decay can be fully reconstructed. …

In the past decades, there has been increasing interest in pulsed high power RF sources for building high-gradient high-energy particle accelerators. Passive RF pulse compression systems have been used in many applications to match the available RF sources to the loads requiring higher RF power but a shorter pulse. Theoretically, an active RF pulse compression system has the advantage of higher efficiency and compactness over the passive system. However, the key component for such a system an element capable of switching hundreds of megawatts of RF power in a short time compared to the compressed pulse width is still an open problem. In this dissertation, we present a switch module composed of an active window based on the bulk effects in semiconductor, a circular waveguide three-port network and a movable short plane, with the capability to adjust the S-parameters before and after switching. The RF properties of the switch module were analyzed. We give the scaling laws of the multiple-element switch systems, which allow the expansion of the system to a higher power level. We present a novel overmoded design for the circular waveguide three-port network and the associated circular-to-rectangular mode-converter. We also detail the design and synthesis process of …

Performance in H-mode DT plasmas in ITER with various choices of heating systems are predicted and compared. Combinations of external heating by Negative Ion Neutral Beam Injection (NNBI), Ion Cyclotron Range of Frequencies (ICRF), and Electron Cyclotron Heating (ECH) are assumed. Scans with a range of physics assumptions about boundary temperatures in the edge pedestal, alpha ash transport, and toroidal momentum transport are used to indicate effects of uncertainties. Time-dependent integrated modeling with the PTRANSP code is used to predict profiles of heating, beam torque, and plasma profiles. The GLF23 model is used to predict temperature profiles. Either GLF23 or the assumption of a constant ratio for χø/χi is used to predict toroidal rotation profiles driven by the beam torques. Large differences for the core temperatures are predicted with different mixes of the external heating during the density and current ramp-up phase, but the profiles are similar during the flattop phase. With χø/χi = 0.5, the predicted toroidal rotation is relatively slow and the flow shear implied by the pressure, toroidal rotation, and neoclassical poloidal rotation are not sufficient to cause significant changes in the energy transport or steady state temperature profiles. The GLF23-predicted toroidal rotation is faster by a …

The Pacific Northwest National Laboratory (PNNL) is developing and implementing a customer satisfaction assessment program (CSAP) to assess the quality of research and development provided by the laboratory. We present the customer survey component of the PNNL CSAP. The customer survey questionnaire is composed of 2 major sections, Strategic Value and Project Performance. The Strategic Value section of the questionnaire consists of 5 questions that can be answered with a 5 point Likert scale response. These questions are designed to determine if a project is directly contributing to critical future national needs. The Project Performance section of the questionnaire consists of 9 questions that can be answered with a 5 point Likert scale response. These questions determine PNNL performance in meeting customer expectations. Many approaches could be used to analyze customer survey data. We present a statistical model that can accurately capture the random behavior of customer survey data. The properties of this statistical model can be used to establish a "gold standard'' or performance expectation for the laboratory, and then assess progress. The gold standard is defined from input from laboratory management --- answers to 4 simple questions, in terms of the information obtained from the CSAP customer survey, …

A linear array of four small biased electrodes was installed in NSTX in an attempt to control the width of the scrape-off layer (SOL) by creating a strong local poloidal electric field. The set of electrodes were separated poloidally by a 1 cm gap between electrodes and were located slightly below the midplane of NSTX, 1 cm behind the RF antenna and oriented so that each electrode is facing approximately normal to the magnetic field. Each electrode can be independently biased to ±100 volts. Present power supplies limit the current on two electrodes to 30 amps the other two to 10 amps each. The effect of local biasing was measured with a set of Langmuir probes placed between the electrodes and another set extending radially outward from the electrodes, and also by the gas puff imaging diagnostic (GPI) located 1 m away along the magnetic field lines intersecting the electrodes. Two fast cameras were also aimed directly at the electrode array. The hardware and controls of the biasing experiment will be presented and the initial effects on local plasma parameters will be discussed.

The primary objective of this task was to perform a variability study of the high activity waste (HAW) acidic feed to determine the impact of feed variability on the quality of the final grout and on the mixability of the salt solution into the dry powders. The HAW acidic feeds were processed through the neutralization/pH process, targeting a final pH of 12. These fluids were then blended with the dry materials to make the final waste forms. A secondary objective was to determine if elemental substitution for cost prohibitive or toxic elements in the simulant affects the mixing response, thus providing a more economical simulant for use in full scale tests. Though not an objective, the HAW simulant used in the full scale tests was also tested and compared to the results from this task. A statistically designed test matrix was developed based on the maximum molarity inputs used to make the acidic solutions. The maximum molarity inputs were: 7.39 HNO{sub 3}, 0.11618 gallium, 0.5423 silver, and 1.1032 'other' metals based on their NO{sub 3}{sup -} contribution. Substitution of the elements aluminum for gallium and copper for silver was also considered in this test matrix, resulting in a total of …

Compared to conventional particle accelerators, plasmas can sustain accelerating fields that are thousands of times higher. To exploit this ability, massively parallel SciDAC particle simulations provide physical insight into the development of next-generation accelerators that use laser-driven plasma waves. These plasma-based accelerators offer a path to more compact, ultra-fast particle and radiation sources for probing the subatomic world, for studying new materials and new technologies, and for medical applications.