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Modeling an optical micromachine probe

Mittas, Anthony

Silicon micromachines are fabricated using Surface Micro-Machining (SMM) techniques. Silicon micromachines include engines that consist of orthogonally oriented linear comb drive actuators mechanically connected to a rotating gear. These gears are as small a 50-{micro}m in diameter and can be driven at rotation rates exceeding 300,000-rpm. Measuring and analyzing microengine performance is basic to micromachine development and system applications. Optical techniques offer the potential for measuring long term statistical performance data and transient responses needed to optimize designs and manufacturing techniques. The authors describe the modeling of an optical probe developed at Sandia National Laboratories. Experimental data will be compared with output from the model.

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Beyond pretty pictures: Quantifying porous media properties and transport processes using transmission and emission CT

Lucero, Daniel A.

While gaining increasing interest, the use of Computerized Tomography (CT) in porous media studies has been limited by the availability of quantitative methods of analysis. Three methods are presented for the analysis of CT data and applied to images obtained from gamma transmission and gamma emission systems. The first utilizes measurement statistics and image histograms to provide exact estimates of multiple component volume contents. An improved thresholding technique in the second method allows an identification of individual voxel composition. The threshold utilizes error statistics to eliminate the arbitrary nature of current methods. Emission tomography images of solute transport are shown in the third procedure to provide in-situ measures of transport in fractured media. Application of each method is demonstrated on samples of the Culebra Dolomite of the Rustler Formation, New Mexico. Dolomite cores were collected by horizontal drilling at a depth of 218 m in the air intake shaft of the Waste Isolation Pilot Plant located near Carlsbad, New Mexico.

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VSHOT measurement uncertainty and sensitivity study

Jones, Scott A.

The Video Scanning Hartmann Optical Tester (VSHOT) is a slope-measuring tool for large, imprecise reflectors. It is a laser ray trace device developed to measure the optical quality of point-focus solar concentrating mirrors. A unique tool was needed because of the diverse geometry and very large size of solar concentrators, plus their large optical errors. To study the accuracy of VSHOT as well as its sensitivity to changes in test setup variables, a series of experiments were performed with a very precise, astronomical-grade mirror. The slope errors of the reference mirror were much smaller than the resolution of the VSHOT, so that any measured slope errors were caused by the instrument itself rather than the mirror. The VSHOT exceeded its accuracy goals by achieving about {+-}0.5% (68% confidence) error in the determination of focal length and {+-} 0.1 mrad (68% confidence) error in the determination of RMS slope error. Displacement of the test mirror from the optical axis caused the largest source of measured errors.

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Virtual Tower

Wayne, R.A.

The primary responsibility of an intrusion detection system (IDS) operator is to monitor the system, assess alarms, and summon and coordinate the response team when a threat is acknowledged. The tools currently provided to the operator are somewhat limited: monitors must be switched, keystrokes must be entered to call up intrusion sensor data, and communication with the response force must be maintained. The Virtual tower is an operator interface assembled from low-cost commercial-off-the-shelf hardware and software; it enables large amounts of data to be displayed in a virtual manner that provides instant recognition for the operator and increases assessment accuracy in alarm annunciator and control systems. This is accomplished by correlating and fusing the data into a 360-degree visual representation that employs color, auxiliary attributes, video, and directional audio to prompt the operator. The Virtual Tower would be a valuable low-cost enhancement to existing systems.

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An introduction to the architectural surety program

Matalucci, R.V.

This paper provides a summary introduction to the nationally emerging area of Architectural and Infrastructure Surety that is under development at Sandia National Laboratories. This program area, addressing technology requirements at the national level, includes four major elements: education, research, development, and application. It involves a risk management approach to solving problems of the as-built environment through the application of security, safety, and reliability principles developed in the nuclear weapons programs of the Department of Energy. The changing responsibilities of engineering design professionals is addressed in light of the increased public awareness of structural and facility systems vulnerabilities to malevolent, normal, and abnormal environment threats. A brief discussion is presented of the education and technology outreach programs initiated through an infrastructure surety graduate Civil Engineering Department course taught at the University of New Mexico and through the architectural surety workshops and conferences already held and planned for the future. A summary description is also presented of selected technologies with strong potential for application to specific national architectural and infrastructure surety concerns. These technologies include super-computational modeling and structural simulations, window glass fragmentation modeling, risk management procedures, instrumentation and health monitoring systems, and three-dimensional CAD virtual reality visualization techniques.

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Application of spatial and angular domain based parallelism to a discrete ordinates formulation with unstructured spatial discretization

Burns, Shawn P.

A parallel discrete ordinate formulation employing a general, unstructured finite element spatial discretization is presented for steady, gray, nonscattering radiative heat transport within a participating medium. The formulation is based on the first order form of the boltzmann transport equation and allows for any combination of spatial and angular domain based parallelism. The formulation is tested on a massively parallel, distributed memory architecture using a standard three-dimensional benchmark calculation. The results show that the formulation presented provides better parallel performance and accuracy than the author`s previously published work. The ultimate objective of both the current and previous efforts is to develop a computationally efficient radiative transport model for use in large scale numerical fire simulations.

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Risk management for buildings -- Has the time come?

Berry, Dennis L.

There are both incentives and challenges for applying formal risk management processes to buildings and other structures, including bridges, highways, dams, stadiums, shopping centers, and private dwellings. Based on an assessment of several issues, the authors conclude that for certain types of buildings and structures the time has come for the use of a formal risk-management approach, including probabilistic risk assessment methods, to help identify dominant risks to public health, safety, and security and to help manage these risks in a cost-effective manner.

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A thin-foil Faraday collector as a radiation-hard, high fluence charged particle spectrometer

Barbour, J.C.

The authors have developed a radiation-hard, charged particle spectrometer, consisting of thin parallel conducting foils as current collectors. Prototype detectors have been tested in accelerator bombardments and at the fusion plasma facilities TFTR and JET. In the case of the accelerator bombardments, a detector consisting of 6 Al foils, each of thickness about 6 {micro}m, demonstrated an energy resolution of about 7% for 7 MeV alpha particles. The prototype tested immediately outside TFTR demonstrated the expected insensitivity to moderately high levels of fast neutrons and hard gamma rays. The prototype tested inside JET similarly indicated operational capability at elevated temperatures as a lost alpha particle detector for d-t tokamak fusion plasmas. The robustness and moderately good energy resolution of these detectors should permit the application to tasks such as the first wall measurement of lost alpha particles from tokamak fusion plasmas, the real time measurement of light ion fission fragments from fission reactor experiments and the in-beam measurement of accelerator beam energies as a control diagnostic.

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Contents and structure of the SME digital signature buffer

Tarman, Thomas D.

This contribution proposes additional text for Section 7.1.5.5 of [1] which defines the contents of the digital signature buffer for each relevant flow in the Two-Way and Three-Way Security Message Exchange Protocols. This is clearly an interoperability issue because these signature buffers must be constructed identically at the sender (signature generator) and receiver (signature validator) in order for the protocols to proceed correctly. Sections 2 and 3 of this contribution are intended to be placed in Section 7.1.5.5 of [1]. In addition, text is proposed in Motion 2 of Section 4 of this contribution which clarifies the scope of encryption of the Confidential Section, which is defined in Section 7.1.4 of [1].

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An information model based weld schedule database

Kleban, Stephen

As part of a computerized system (SmartWeld) developed at Sandia National Laboratories to facilitate agile manufacturing of welded assemblies, a weld schedule database (WSDB) was also developed. SmartWeld`s overall goals are to shorten the design-to-product time frame and to promote right-the-first-time weldment design and manufacture by providing welding process selection guidance to component designers. The associated WSDB evolved into a substantial subproject by itself. At first, it was thought that the database would store perhaps 50 parameters about a weld schedule. This was a woeful underestimate: the current WSDB has over 500 parameters defined in 73 tables. This includes data bout the weld, the piece parts involved, the piece part geometry, and great detail about the schedule and intervals involved in performing the weld. This complex database was built using information modeling techniques. Information modeling is a process that creates a model of objects and their roles for a given domain (i.e. welding). The Natural-Language Information Analysis methodology (NIAM) technique was used, which is characterized by: (1) elementary facts being stated in natural language by the welding expert, (2) determinism (the resulting model is provably repeatable, i.e. it gives the same answer every time), and (3) extensibility (the model can be added to without changing existing structure). The information model produced a highly normalized relational schema that was translated to Oracle{trademark} Relational Database Management Systems for implementation.

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Equilibrium characteristics of tartrate and EDTA-based electroless copper deposition baths

Chen, Ken S.

Electroless deposition of copper is being used for a variety of applications, one of them being the development of seed metallic layers on non-metals, which are widely used in electronic circuitry. Solution equilibrium characteristics of two electroless copper baths containing EDTA and tartrate as the complexing agents were studied as functions of pH, chelating agent and metal ion concentrations. Equilibrium diagrams were constructed for both cu-tartrate and Cu-EDTA systems. It was determined that copper is chiefly complexed as Cu(OH){sub 2}L{sub 2}{sup {minus}4} in the tartrate bath, and as CuA{sup {minus}2} in the EDTA bath, where L and A are the complexing tartrate and EDTA ligands, respectively. The operating ranges for electroless copper deposition were identified for both baths. Dependence of Cu(OH){sub 2} precipitation on the pH and species concentrations was also studied for these systems.

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A plasma process monitor/control system

Stevenson, Joel O.

Sandia National Laboratories has developed a system to monitor plasma processes for control of industrial applications. The system is designed to act as a fully automated, sand-alone process monitor during printed wiring board and semiconductor production runs. The monitor routinely performs data collection, analysis, process identification, and error detection/correction without the need for human intervention. The monitor can also be used in research mode to allow process engineers to gather additional information about plasma processes. The plasma monitor can perform real-time control of support systems known to influence plasma behavior. The monitor can also signal personnel to modify plasma parameters when the system is operating outside of desired specifications and requires human assistance. A notification protocol can be selected for conditions detected in the plasma process. The Plasma Process Monitor/Control System consists of a computer running software developed by Sandia National Laboratories, a commercially available spectrophotometer equipped with a charge-coupled device camera, an input/output device, and a fiber optic cable.

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Architectural design for reliability

Cranwell, Robert M.

Design-for-reliability concepts can be applied to the products of the construction industry, which includes buildings, bridges, transportation systems, dams, and other structures. The application of a systems approach to designing in reliability emphasizes the importance of incorporating uncertainty in the analyses, the benefits of optimization analyses, and the importance of integrating reliability, safety, and security. 4 refs., 3 figs.

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On angularly perturbed Laplace equations in the unit ball of IR{sup n+2} and their distributional boundary values

Massopust, P.R.

All solutions of an in its angular coordinates continuously perturbed Laplace-Beltrami equation in the open unit ball IB{sup n+2} {contained_in} IR{sup n+2}, n {ge} 1, are characterized. Moreover, it is shown that such pertubations yield distributional boundary values which are different from, but algebraically and topologically equivalent to, the hyperfunctions of Lions & Magenes. This is different from the case of radially perturbed Laplace-Beltrami operators (cf. [7]) where one has stability of distributional boundary values under such perturbations.

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Activity-based costing of security services for a Department of Energy nuclear site

Snell, Mark K.

Department of Energy (DOE) nuclear facilities are being encouraged to reduce costs but the accounting data typically in use by the financial organizations at these laboratories cannot easily be used to determine which security activities offer the best reduction in cost. For example, labor costs have historically been aggregated over various activities, making it difficult to determine the true costs of performing each activity. To illustrate how this problem can be solved, a study was performed applying activity-based costing (ABC) to a hypothetical DOE facility. ABC is a type of cost-accounting developed expressly to determine truer costs of company activities. The hypothetical facility was defined to have features similar to those found across the DOE nuclear complex. ABC traced costs for three major security functions - Protective Force Operations, Material Control and Accountability, and Technical Security - to various activities. Once these costs had been allocated, we compared the cost of three fictitious upgrades: (1) an improvement in training or weapons that allows the protective force to have better capabilities instead of adding more response forces; (2) a change in the frequency of inventories; and (3) a reduction in the annual frequencies of perimeter sensor tests.

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Evaluation of a prototype infrasound system

Breding, D.

Under Department of Energy sponsorship, Sandia National Laboratories and Los Alamos National Laboratory cooperated to develop a prototype infrasonic array, with associated documentation, that could be used as part of the International Monitoring System. The United States Government or foreign countries could procure commercially available systems based on this prototype to fulfill their Comprehensive Test Ban Treaty (CTBT) obligations. The prototype is a four-element array in a triangular layout as recommended in CD/NTB/WP.224 with an element at each corner and one in the center. The prototype test configuration utilize an array spacing of 1 km. The prototype infrasound system has the following objectives: (1) Provide a prototype that reliably acquires and transmits near real-time infrasonic data to facilitate the rapid location and identification of atmospheric events. (2) Provide documentation that could be used by the United States and foreign countries to procure infrasound systems commercially to fulfill their CTBT responsibilities. Infrasonic monitoring is an effective, low cost technology for detecting atmospheric explosions. The low frequency components of explosion signals propagate to long ranges (few thousand kilometers) where they can be detected with an array of sensors. Los Alamos National Laboratory`s expertise in infrasound systems and phenomenology when combined with Sandia`s expertise in providing verification quality system for treaty monitoring make an excellent team to provide the prototype infrasound sensor system. By September 1997, the prototype infrasound system will have been procured, integrated, evaluated and documented. Final documentation will include a system requirements document, an evaluation report and a hardware design document. The hardware design document will describe the various hardware components used in the infrasound prototype and their interrelationships.

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Oxidation in HVOF-sprayed steel

Smith, Mark F.

It is widely held that most of the oxidation in thermally sprayed coatings occurs on the surface of the droplet after it has flattened. The evidence in this paper suggests that, for the conditions studied here, oxidation of the top surface of flattened droplets is not the dominant oxidation mechanism. In this study, a mild steel wire (AISI 1025) was sprayed using a high-velocity oxy-fuel (HVOF) torch onto copper and aluminum substrates. Ion milling and Auger spectroscopy were used to examine the distribution of oxides within individual splats. Conventional metallographic analysis was also used to study oxide distributions within coatings that were sprayed under the same conditions. An analytical model for oxidation of the exposed surface of a splat is presented. Based on literature data, the model assumes that diffusion of iron through a solid FeO layer is the rate limiting factor in forming the oxide on the top surface of a splat. An FeO layer only a few thousandths of a micron thick is predicted to form on the splat surface as it cools. However, the experimental evidence shows that the oxide layers are typically 100x thicker than the predicted value. These thick, oxide layers are not always observed on the top surface of a splat. Indeed, in some instances the oxide layer is on the bottom, and the metal is on the top. The observed oxide distributions are more consistently explained if most of the oxide formed before the droplets impact the substrate.

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Travel-time correction surface generation for the DOE Knowledge Base

Hipp, James R.

The DOE Knowledge Base data storage and access model consists of three parts: raw data processing, intermediate surface generation, and final output surface interpolation. The paper concentrates on the second step, surface generation, specifically applied to travel-time correction data. The surface generation for the intermediate step is accomplished using a modified kriging solution that provides robust error estimates for each for each interpolated point and satisfies many important physical requirements including differing quality data points, user-definable range of influence for each point, blend to background values for both interpolated values and error estimates beyond the ranges, and the ability to account for the effects of geologic region boundaries. These requirements are outlined and discussed and are linked to requirements specified for the final output model in the DOE Knowledge Base. Future work will focus on testing the entire Knowledge Base model using the regional calibration data sets which are being gathered by researchers at Los Alamos and Lawrence Livermore National Laboratories.

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Visualization tools for comprehensive test ban treaty research

Edwards, T.L.

This paper focuses on tools used in Data Visualization efforts at Sandia National Laboratories under the Department of Energy CTBT R&D program. These tools provide interactive techniques for the examination and interpretation of scientific data, and can be used for many types of CTBT research and development projects. We will discuss the benefits and drawbacks of using the tools to display and analyze CTBT scientific data. While the tools may be used for everyday applications, our discussion will focus on the use of these tools for visualization of data used in research and verification of new theories. Our examples focus on uses with seismic data, but the tools may also be used for other types of data sets. 5 refs., 6 figs., 1 tab.

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The software engineering journey: From a naieve past into a responsible future

Fitzpatrick-Fletcher, Sharon K.

All engineering fields experience growth, from early trial & error approaches, to disciplined approaches based on fundamental understanding. The field of software engineering is making the long and arduous journey, accomplished by evolution of thinking in many dimensions. This paper takes the reader along a trio of simultaneous evolutionary paths. First, the reader experiences evolution from a zero-risk mindset to a managed-risk mindset. Along this path, the reader observes three generations of security risk management and their implications for software system assurance. Next is a growth path from separate surety disciplines to an integrated systems surety approach. On the way, the reader visits safety, security, and dependability disciplines and peers into a future vision which coalesces them. The third and final evolutionary path explored here transitions the software engineering field from best practices to fundamental understanding. Along this road, the reader observes a framework for developing a {open_quotes}science behind the engineering{close_quotes}, and methodologies for software surety analysis.

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A summary of the GPS system performance for STARS Mission 3

Creel, E.E.

This paper describes the performance of the GPS system on the most recent flight of the STARS missile, STARS Mission 3 (M3). This mission was conducted under the Ballistic Missile Defense Organization`s (BMDO`s) Consolidated Targets Program. The United States Army Space and Strategic Defense Command (USASSDC) is the executing agent for this mission and the Department of Energy`s (DOE`s) Sandia National Laboratories (SNL) is the vehicle developer and integrator. The M3 flight, dually designated as the MSX Dedicated Targets II (MDT-II) mission occurred on August 31, 1996. This mission was conducted for the specific purpose of providing targets for viewing by the MSX satellite. STARS M3 was the first STARS flight to use GPS-derived data for missile guidance, and proved to be instrumental in the procurement of a wealth of experimental data which is still undergoing analysis by numerous scientific agencies within the BMDO complex. GPS accuracy was required for this mission because of the prescribed targeting requirements for the MDT-II payload deliveries with respect to the MSX satellite flight path. During the flight test real time GPS-derived state vector data was also used to generate pointing angles for various down range sensors involved in the experiment. Background information describing the STARS missile, GPS subsystem architecture, and the GPS Kalman filter design is presented first, followed by a discussion of the telemetry data records obtained from this flight with interpretations and conclusions.

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The data dictionary: A view into the CTBT knowledge base

Shepherd, E.R.; Keyser, R.G.; Armstrong, H.M.

The data dictionary for the Comprehensive Test Ban Treaty (CTBT) knowledge base provides a comprehensive, current catalog of the projected contents of the knowledge base. It is written from a data definition view of the knowledge base and therefore organizes information in a fashion that allows logical storage within the computer. The data dictionary introduces two organization categories of data: the datatype, which is a broad, high-level category of data, and the dataset, which is a specific instance of a datatype. The knowledge base, and thus the data dictionary, consist of a fixed, relatively small number of datatypes, but new datasets are expected to be added on a regular basis. The data dictionary is a tangible result of the design effort for the knowledge base and is intended to be used by anyone who accesses the knowledge base for any purpose, such as populating the knowledge base with data, or accessing the data for use with automatic data processing (ADP) routines, or browsing through the data for verification purposes. For these two reasons, it is important to discuss the development of the data dictionary as well as to describe its contents to better understand its usefulness; that is the purpose of this paper.

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Testing the waveform correlation event detection system: Teleseismic, regional, and local distances

Young, Christopher J.

Waveform Correlation Event Detection System (WCEDS) prototypes have now been developed for both global and regional networks and the authors have extensively tested them to assess the potential usefulness of this technology for CTBT (Comprehensive Test Ban Treaty) monitoring. In this paper they present the results of tests on data sets from the IDC (International Data Center) Primary Network and the New Mexico Tech Seismic Network. The data sets span a variety of event types and noise conditions. The results are encouraging at both scales but show particular promise for regional networks. The global system was developed at Sandia Labs and has been tested on data from the IDC Primary Network. The authors have found that for this network the system does not perform at acceptable levels for either detection or location unless directional information (azimuth and slowness) is used. By incorporating directional information, however, both areas can be improved substantially suggesting that WCEDS may be able to offer a global detection capability which could complement that provided by the GA (Global Association) system in use at the IDC and USNDC (United States National Data Center). The local version of WCEDS (LWCEDS) has been developed and tested at New Mexico Tech using data from the New Mexico Tech Seismic Network (NMTSN). Results indicate that the WCEDS technology works well at this scale, despite the fact that the present implementation of LWCEDS does not use directional information. The NMTSN data set is a good test bed for the development of LWCEDS because of a typically large number of observed local phases and near network-wide recording of most local and regional events. Detection levels approach those of trained analysts, and locations are within 3 km of manually determined locations for local events.

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Software design and operational model for the WCEDS prototype

Beiriger, Judy I.

To explore the potential of waveform correlation for CTBT, the Waveform Correlation Event Detection System (WCEDS) prototype was developed. The WCEDS software design followed the Object Modeling Technique process of analysis, system design, and detailed design and implementation. Several related executable programs are managed through a Graphical User Interface (GUI). The WCEDS prototype operates in an IDC/NDC-compatible environment. It employs a CSS 3.0 database as its primary input/output interface, reading in raw waveforms at the start, and storing origins, events, arrivals, and associations at the finish. Additional output includes correlation results and data for specified testcase origins, and correlation timelines for specified locations. During the software design process, the more general seismic monitoring functionality was extracted from WCEDS-specific requirements and developed into C++ object-oriented libraries. These include the master image, grid, basic seismic, and extended seismic libraries. Existing NDC and commercial libraries were incorporated into the prototype where appropriate, to focus development activities on new capability. The WCEDS-specific application code was built in a separate layer on top of the general seismic libraries. The general seismic libraries developed for the WCEDS prototype can provide a base for other algorithm development projects.

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Magnetically-excited flexural plate wave resonator

Martin, Steve W.

A flexural plate wave (FPW) resonator was constructed by patterning current lines on a silicon nitride membrane suspended on a rectangular silicon frame. Eigenmodes of the rectangular membrane were excited using Lorentz forces generated between alternating surface currents and a static in-plane magnetic field. The magnetic field strength required for these devices can be achieved with small permanent magnets ({approx} 1 cm{sup 3}). Preferential coupling to a particular membrane mode was achieved by positioning current lines along longitudinal mode antinodes. An equivalent-circuit model was derived that characterizes the input impedance of a one-port device and the transmission response of a two-port device over a range of frequencies near a single membrane resonance. Experiments were performed to characterize the effects of varying magnetic field, ambient gas, gas pressure, and input power. To the authors` knowledge, this is the first experimental demonstration of a resonant FPW device.

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Results 93751–93775 of 99,299
Results 93751–93775 of 99,299