Science.gov

Sample records for sawing

  1. Saw Palmetto

    MedlinePLUS

    ... health approaches, including publications and searches of Federal databases of scientific and medical literature. The Clearinghouse does ... June 3, 2010. Saw palmetto. Natural Medicines Comprehensive Database Web site. Accessed at www.naturaldatabase.com on ...

  2. Saw palmetto

    MedlinePLUS

    ... However, it is not known if it is safe to use for longer periods of time. Special precautions & warnings: Pregnancy and breast-feeding: Saw palmetto is LIKELY UNSAFE when used during pregnancy or breast-feeding. It acts like a hormone, and this could be dangerous ...

  3. Constant-Pressure Sawing

    NASA Technical Reports Server (NTRS)

    Orris, G. M.; Gerrety, J. F.

    1986-01-01

    Attachment for reciprocating power-saw maintains nearly constant cutting pressure even though kerf length varies. Attachment developed for wire saws used to slice cylindrical silicon ingots into wafers for semiconductor devices. By maintaining constant pressure, attachment helps to ensure smooth, flat, uniform wafers. Principle adaptable to straight, toothed saws as well as to wire saws.

  4. Gin saw wear test

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most current gin saw manufacturers use a 1074 steel or similar as a basis to manufacture their saw blades. The saw teeth are individually punched on the edges of the blades and then the blade goes through a heat treating process prior to use. There are indications from other industries with similar ...

  5. See-Saw Jeans

    ERIC Educational Resources Information Center

    Sutton, Charlotte D.

    2005-01-01

    This article describes the following case: Pete Wilmington, Vice President of Sales for See-Saw Jeans for Kids, has wrapped up a deal with Wal-Mart to carry See-Saw Jeans for Kids in all Wal-Mart stores on a trial basis for the next year. See-Saw Jeans for Kids is a clothing manufacturer with sales of $41 million, but the Wal-Mart account has the…

  6. Safe Chain Saw Operation. 

    E-print Network

    Nelson, Gary S.

    1982-01-01

    and handling characteristics. Keep Zerle L. Carpenter, Director College Station The Texas A&M University System J unnecessary helpers or bystanders away from saw operations. Cut small logs supported off the ground so the chain will not strike... obstacles. Always carry the saw, whether it is idling or stopped, with the muffler away from your body. Be aware of helpers or bystanders. Making a Cut When making a cut, hold the saw securely with both hands. Make sure your thumbs and fingers...

  7. 29 CFR 570.65 - Occupations involving the operation of circular saws, band saws, guillotine shears, chain saws...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...chain saws, reciprocating saws, wood chippers, and abrasive cutting discs (Order...chain saws, reciprocating saws, wood chippers, and abrasive cutting discs (Order...Reciprocating saws. (iii) Wood chippers. (iv) Abrasive cutting...

  8. 29 CFR 570.65 - Occupations involving the operation of circular saws, band saws, guillotine shears, chain saws...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...chain saws, reciprocating saws, wood chippers, and abrasive cutting discs (Order...chain saws, reciprocating saws, wood chippers, and abrasive cutting discs (Order...Reciprocating saws. (iii) Wood chippers. (iv) Abrasive cutting...

  9. 29 CFR 570.65 - Occupations involving the operation of circular saws, band saws, guillotine shears, chain saws...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...chain saws, reciprocating saws, wood chippers, and abrasive cutting discs (Order...chain saws, reciprocating saws, wood chippers, and abrasive cutting discs (Order...Reciprocating saws. (iii) Wood chippers. (iv) Abrasive cutting...

  10. Electric arc saw apparatus

    DOEpatents

    Deichelbohrer, Paul R [Richland, WA

    1986-01-01

    A portable, hand held electric arc saw has a small frame for supporting an electrically conducting rotary blade which serves as an electrode for generating an electric arc to erode a workpiece. Electric current is supplied to the blade by biased brushes and a slip ring which are mounted in the frame. A pair of freely movable endless belts in the form of crawler treads stretched between two pulleys are used to facilitate movement of the electric arc saw. The pulleys are formed of dielectric material to electrically insulate the crawler treads from the frame.

  11. Rapid SAW Sensor Development Tools

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Atkinson, Gary M.

    2007-01-01

    The lack of integrated design tools for Surface Acoustic Wave (SAW) devices has led us to develop tools for the design, modeling, analysis, and automatic layout generation of SAW devices. These tools enable rapid development of wireless SAW sensors. The tools developed have been designed to integrate into existing Electronic Design Automation (EDA) tools to take advantage of existing 3D modeling, and Finite Element Analysis (FEA). This paper presents the SAW design, modeling, analysis, and automated layout generation tools.

  12. Electric arc saw apparatus

    DOEpatents

    Deichelbohrer, P.R.

    1983-08-08

    A portable, hand-held electric arc saw apparatus comprising a small frame for supporting an electrically conducting rotary blade which serves as an electrode for generating an electric arc between the blade and a workpiece of opposite polarity. Electrically conducting means are provided on said frame for transmitting current to said blade. A pair of freely movable endless belts in the form of crawler treads are employed to facilitate movement of the apparatus relative to the workpiece.

  13. Modeling of SAW Delay Lines

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Atkinson, Gary M.

    2007-01-01

    Integrated Vehicle Health Monitoring (IVHM) of aerospace vehicles requires rugged sensors having reduced volume, mass, and power that can be used to measure a variety of phenomena. Wireless systems are preferred when retro-fitting sensors onto existing vehicles. Surface Acoustic Wave (SAW) devices are capable of sensing: temperature, pressure, strain, chemical species, mass loading, acceleration, and shear stress. SAW technology is low cost, rugged, lightweight, and extremely low power. To aid in the development of SAW sensors for IVHM applications, a first order model of a SAW Delay line has been created.

  14. The sawing machine is a machine SAWING MACHINES

    E-print Network

    Gellman, Andrew J.

    wheel and an idler wheel support and drive the blade. POWER HACKSAW MACHINES DESCRIPTION All power-524 Some machines feed by gravity, the saw frame having weights that can be shifted to give greater or less that contains the saw band idler wheel, the drive motor switch, the tension adjustment handwheel and mechanism

  15. 29 CFR 570.65 - Occupations involved in the operations of circular saws, band saws, guillotine shears, chain saws...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., band saws, guillotine shears, chain saws, reciprocating saws, wood chippers, and abrasive cutting discs..., guillotine shears, chain saws, reciprocating saws, wood chippers, and abrasive cutting discs (Order 14). (a.... (iii) Wood chippers. (iv) Abrasive cutting discs. (3) The occupations of setting-up,...

  16. SAW correlator spread spectrum receiver

    DOEpatents

    Brocato, Robert W

    2014-04-01

    A surface acoustic wave (SAW) correlator spread-spectrum (SS) receiver is disclosed which utilizes a first demodulation stage with a chip length n and a second demodulation stage with a chip length m to decode a transmitted SS signal having a code length l=n.times.m which can be very long (e.g. up to 2000 chips or more). The first demodulation stage utilizes a pair of SAW correlators which demodulate the SS signal to generate an appropriate code sequence at an intermediate frequency which can then be fed into the second demodulation stage which can be formed from another SAW correlator, or by a digital correlator. A compound SAW correlator comprising two input transducers and a single output transducer is also disclosed which can be used to form the SAW correlator SS receiver, or for use in processing long code length signals.

  17. Lunar stone saw

    NASA Technical Reports Server (NTRS)

    Clark, Tom; Croker, Todd; Hines, Ken; Knight, Mike; Walton, Todd

    1988-01-01

    This project addresses the problem of cutting lunar stones into blocks to be used to construct shelters to protect personnel and equipment from harmful solar radiation. This plant will manufacture 6 in x 1 ft x 2 ft blocks and will be located near the south pole to allow it to be in the shade at all times. This design uses a computer controlled robot, a boulder handler that uses hydraulics for movement, a computer system that used 3-D vision to determine the size of boulders, a polycrystalline diamond tipped saw blade that utilizes radiation for cooling, and a solar tower to collect solar energy. Only two electric motors are used in this plant because of the heavy weight of electric motors and the problem of cooling them. These two motors will be cooled by thermoelectric cooling. All other motors and actuators are to be hydraulic. The architectural design for the building as well as the conceptual design of the machines for cutting the blocks are described.

  18. Reconstructing see-saw models

    SciTech Connect

    Ibarra, Alejandro

    2007-01-12

    In this talk we discuss the prospects to reconstruct the high-energy see-saw Lagrangian from low energy experiments in supersymmetric scenarios. We show that the model with three right-handed neutrinos could be reconstructed in theory, but not in practice. Then, we discuss the prospects to reconstruct the model with two right-handed neutrinos, which is the minimal see-saw model able to accommodate neutrino observations. We identify the relevant processes to achieve this goal, and comment on the sensitivity of future experiments to them. We find the prospects much more promising and we emphasize in particular the importance of the observation of rare lnic decays for the reconstruction of the right-handed neutrino masses.

  19. Frequency Domain Modeling of SAW Devices

    NASA Technical Reports Server (NTRS)

    Wilson, W. C.; Atkinson, G. M.

    2007-01-01

    New SAW sensors for integrated vehicle health monitoring of aerospace vehicles are being investigated. SAW technology is low cost, rugged, lightweight, and extremely low power. However, the lack of design tools for MEMS devices in general, and for Surface Acoustic Wave (SAW) devices specifically, has led to the development of tools that will enable integrated design, modeling, simulation, analysis and automatic layout generation of SAW devices. A frequency domain model has been created. The model is mainly first order, but it includes second order effects from triple transit echoes. This paper presents the model and results from the model for a SAW delay line device.

  20. Comparison of various silicon sawing methods

    NASA Technical Reports Server (NTRS)

    Wolf, M.

    1982-01-01

    The technology and economics of four methods of wafering silicon boules of large cross section are described. Slurry sawing using either blades or wires, and fixed abrasive sawing using the ID saw or by the FAST method, having the abrasive attached to wires which are arranged in a blade pack, are considered. The technical performance of each method is evaluated and cost/price estimates are summarized.

  1. SAW filter basics guide designer choices

    NASA Astrophysics Data System (ADS)

    Monetti, G. A.; Hays, R. M., Jr.

    1983-11-01

    It is pointed out that a common pitfall of the systems engineer seeking a surface acoustic wave (SAW) filter is a tendency to think in terms of the characteristics of other technologies, such as LC filters. However, SAW specifications should be approached as unique. Attention is given to the contribution to SAW filter losses provided by electrical mismatch, the selection of a matching circuit for a SAW filter, the degradation of both passband and stopband performance of the filter by crosstalk, approaches for controlling crosstalk, and transducer configurations for low loss.

  2. PRECISION SECTIONING SAW Large Cutting Capacity

    E-print Network

    including: · metals · plastics · biomaterials · minerals · ceramics · composites · rocks · electronic. The transparent cutting hood can be removed and replaced with the accessory Table Saw Attachment when sectioning

  3. IEEE ULTRASONICS SYMPOSIUM 1999, LAKE TAHOE, USA 1 SAW Tomography -Spatially Resolved Charge Detection by SAW

    E-print Network

    Ludwig-Maximilians-Universität, München

    for a tunable attenuation and phase shift of the SAW sig- nal. The coupling of the acoustic wave to an electronIEEE ULTRASONICS SYMPOSIUM 1999, LAKE TAHOE, USA 1 SAW Tomography - Spatially Resolved Charge Detection by SAW in Semiconductor Structures for Imaging Applications M. Streibl1 , F. Beil1 , A. Wixforth1

  4. Apparatus for loading a band saw blade

    DOEpatents

    Reeves, Steven R. (49 Williams Ave., West Valley, NY 14171)

    1990-01-01

    A band saw blade is loaded between pairs of guide wheels upon tensioning the blade by guiding the blade between pairs of spaced guide plates which define converging slots that converge toward the guide wheels. The approach is particularly useful in loading blades on underwater band saw machines used to cut radioactive materials.

  5. SAW based systems for mobile communications satellites

    NASA Technical Reports Server (NTRS)

    Peach, R. C.; Miller, N.; Lee, M.

    1993-01-01

    Modern mobile communications satellites, such as INMARSAT 3, EMS, and ARTEMIS, use advanced onboard processing to make efficient use of the available L-band spectrum. In all of these cases, high performance surface acoustic wave (SAW) devices are used. SAW filters can provide high selectivity (100-200 kHz transition widths), combined with flat amplitude and linear phase characteristics; their simple construction and radiation hardness also makes them especially suitable for space applications. An overview of the architectures used in the above systems, describing the technologies employed, and the use of bandwidth switchable SAW filtering (BSSF) is given. The tradeoffs to be considered when specifying a SAW based system are analyzed, using both theoretical and experimental data. Empirical rules for estimating SAW filter performance are given. Achievable performance is illustrated using data from the INMARSAT 3 engineering model (EM) processors.

  6. Parameterizable Library Components for SAW Devices

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Atkinson, Gary M.

    2006-01-01

    To facilitate quick fabrication of Surface Acoustic Wave (SAW) sensors we have found it necessary to develop a library of parameterizable components. This library is the first module in our strategy towards a design tool that is integrated into existing Electronic Design Automation (EDA) tools. This library is similar to the standard cell libraries found in digital design packages. The library cells allow the user to input the design parameters which automatically generate a detailed layout of the SAW component. This paper presents the results of our development of parameterizable cells for an InterDigitated Transducer (IDT), reflector, SAW delay line, and both one and two port resonators.

  7. Versatile machine mills, saws light materials

    NASA Technical Reports Server (NTRS)

    Rauschl, J. A.

    1966-01-01

    Versatile milling/sawing machine performs angle cuts, flat and profile milling, machining of grooves and slots, and edge trimming of phenolic panels. The machine is mounted on rails above a table equipped with vacuum capability for holding workpieces.

  8. SAW Sensor for Fastener Failure Detection

    NASA Technical Reports Server (NTRS)

    Wilson, W. C.; Rogge, M. D.; Fisher, B.; Roller, M. J.; Malocha, D. M.

    2010-01-01

    The proof of concept for using surface acoustic wave (SAW) strain sensors in the detection of aircraft fastener failures is demonstrated. SAW sensors were investigated because they have the potential for the development of passive wireless systems. The SAW devices employed four orthogonal frequency coding (OFC) spread spectrum reflectors in two banks on a high temperature piezoelectric substrate. Three SAW devices were attached to a cantilever panel with removable side stiffeners. Damage in the form of fastener failure was simulated by removal of bolts from the side stiffeners. During testing, three different force conditions were used to simulate static aircraft structural response under loads. The design of the sensor, the panel arrangement and the panel testing results are reported. The results show that the sensors successfully detected single fastener failure at distances up to 54.6 cm from the failure site under loaded conditions.

  9. Chemically sensitive interfaces on SAW devices

    SciTech Connect

    Ricco, A.J.; Martin, S.J.; Crooks, R.M.; Xu, Chuanjing; Allred, R.E.

    1993-11-01

    Using surface acoustic wave (SAW) devices, three approaches to the effective use of chemically sensitive interfaces that are not highly chemically selective have been examined: (1) molecular identification from time-resolved permeation transients; (2) using multifrequency SAW devices to determine the frequency dependence of analyte/film interactions; (3) use of an array of SAW devices bearing diverse chemically sensitive interfaces to produce a distinct response pattern for each analyte. In addition to their well-known sensitivity to mass changes (0.0035 monolayer of N{sub 2} can be measured), SAW devices respond to the mechanical and electronic properties of thin films, enhancing response information content but making a thorough understanding of the perturbation critical. Simultaneous measurement of changes in frequency and attenuation, which can provide the information necessary to determine the type of perturbation, are used as part of the above discrimination schemes.

  10. Passive Wireless SAW Sensors for IVHM

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Perey, Daniel F.; Atkinson, Gary M.; Barclay, Rebecca O.

    2008-01-01

    NASA aeronautical programs require integrated vehicle health monitoring (IVHM) to ensure the safety of the crew and the vehicles. Future IVHM sensors need to be small, light weight, inexpensive, and wireless. Surface acoustic wave (SAW) technology meets all of these constraints. In addition it operates in harsh environments and over wide temperature ranges, and it is inherently radiation hardened. This paper presents a survey of research opportunities for universities and industry to develop new sensors that address anticipated IVHM needs for aerospace vehicles. Potential applications of passive wireless SAW sensors from ground testing to high altitude aircraft operations are presented, along with some of the challenges and issues of the technology.

  11. High Temperature Langasite SAW Oxygen Sensor

    SciTech Connect

    Zheng, Peng; Chin, Tao-Lun; Greve, David; Oppenheim, Irving; Malone, Vanessa; Cao, Limin

    2011-08-01

    High-temperature langasite SAW oxygen sensors using sputtered ZnO as a resistive gas-sensing layer were fabricated and tested. Sensitivity to oxygen gas was observed between 500°C to 700°C, with a sensitivity peak at about 625°C, consistent with the theoretical predictions of the acoustoelectric effect.

  12. Research equipment: Surface Acoustic Wave (SAW) devices

    E-print Network

    Gizeli, Electra

    Research equipment: Surface Acoustic Wave (SAW) devices: Operating frequencies @50MHz, 104MHz, 110, the equipment consists of: i. HP 4195A (10Hz-500MHz) ii. HP 8753ES (30kHz-3GHz) with time-gating option

  13. Mixed orthogonal frequency coded SAW RFID tags.

    PubMed

    Gallagher, Mark W; Malocha, Donald C

    2013-03-01

    Orthogonal frequency coded (OFC) SAW radio-frequency identification (RFID) tags are currently being explored as a multi-sensor platform because of their passive spread-spectrum operation, low loss, and resilience in harsh environments. Ongoing research continues to search for robust device embodiments that increase the number of identifiable codes, in the presence of intersymbol interference, while maintaining reasonable device lengths. This paper presents a technique that shortens the SAW response length while preserving code diversity and bandwidth by utilizing a multi-track SAW configuration. These new devices allow the time response of multiple OFC chips to overlap and yield a mixed-frequency chip having the sum of the chip bandwidths but shorter overall time response. The theoretical development is presented and examples are discussed for these new mixed orthogonal frequency coded (MOFC) SAW devices. Experimental results for MOFC sensors, fabricated on YZ-LiNbO3, with a 7% fractional bandwidth and five chip frequencies in three cells, provide a good contrast to similar OFC designs. Experimental results are presented for the simultaneous operation of eight wireless temperature sensors--four OFC and four MOFC--in a 915-MHz wireless correlator receiver system, highlighting the ability of these devices to operate in the same system. PMID:23475925

  14. New piezoelectric materials for SAW filters

    NASA Astrophysics Data System (ADS)

    Anghelescu, Adrian; Nedelcu, Monica

    2010-11-01

    Scientific research of surface acoustic wave (SAW) devices had an early start by the end of 1960s and led to the development of high frequency and small size piezo devices. A sustained effort was dedicated for these components to be transformed into many more interesting applications for telecom market. Recently the employment of new piezo materials and crystallographic orientations open new opportunities for SAW filters. New piezoelectric crystals of gallium orthophosphate (GaPO4) provide higher electromechanical coupling than quartz, while maintaining temperature compensated characteristics similar to quartz. Based on this material phase transition of 970°C, development of new piezo devices to operate at higher temperatures up to 800°C can be done. SAW velocities about 30% lower than ST-X quartz, favors smaller and more compact devices. Other advantages of GaPO4 are: stability with high resistance to stress induced twinning, 3~4 times higher electromechanical coupling than quartz and existence of SAW temperature compensated orientations. Another family of new materials of the trigonal 32 class has received much attention recently because of their temperature behavior similar to quartz and the promise of higher electromechanical coupling coefficients. It is the family of langasite (LGS, La3Ga5SiO14), langatate (LGT, La3Ga5.5Ta0.5O14) and langanite (La3Ga5.5Nb0.5O14). Langasite crystals, easier to obtain and with the value of electromechanical coupling coefficient intermediate between quartz and lithium tantalate (k2=0.32% for 0°, 140°, 22.5° orientation and k2=0.38% for 0°, 140°, 25° orientation), enable us to design SAW filters with a relative pass band of 0.3% to 0.85%. Other piezoelectric materials are reviewed for comparison.

  15. Improved Multiple-DOF SAW Piezoelectric Motors

    NASA Technical Reports Server (NTRS)

    Bar-Cohen, Yoseph; Bao, Xiaoqi; Hull, Anthony; Wright, John

    2003-01-01

    Surface-acoustic-wave (SAW) piezoelectric motors of a proposed type would be capable of operating in multiple degrees of freedom (DOFs) simultaneously and would be amenable to integration into diverse structures and mechanisms. These motors would be compact and structurally simple and would not contain bearings or lead screws. One example of a particularly useful motor of this type would be a two-dimensional- translation stage. Another such example would be a self-actuated spherical joint that could be made to undergo controlled, simultaneous rotations about two orthogonal axes: Such a motor could serve as a mechanism for aiming an "eyeball" camera or as a compact transducer in, and an integral part of, a joint in a robot arm. The multiple-DOF SAW piezoelectric motors as now proposed would be successors to the ones reported in "Multiple-DOF Surface-Acoustic-Wave Piezoelectric Motors" (NPO-20735), NASA Tech Briefs, Vol. 24, No. 12 (December 2000), page 5b. The basic principle of operation of a multiple-DOF SAW piezoelectric motor is a straightforward extension of that of single-DOF SAW piezoelectric motors, which have been reported in several previous NASA Tech Briefs articles: For example, in the case of a linear SAW piezoelectric motor, piezoelectric transducers at opposite ends of a stator excite surface acoustic waves that travel along the surface of the stator. An object (denoted the slider) is pressed against the stator with sufficient pressure (in practice .300 MPa) that it remains in frictional contact with the stator at all times. The slider rides the crests of the waves and is thereby made to move along the surface of the stator. The direction of motion (forward or backward) is controlled by selecting the relative phase of waves generated by the two piezoelectric transducers. The speed increases with the amplitude of the waves and thus with the magnitude of the voltage applied to the transducers.

  16. 8. GENERAL VIEW OF SHINGLE CUTTING SAWS THAT HANDLE BOLTS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. GENERAL VIEW OF SHINGLE CUTTING SAWS THAT HANDLE BOLTS AFTER DEBARKING; AFTER DEBARKING THE BOLTS ARE SENT TO THE SHINGLE WEAVER FOR SAWING - Lester Shingle Mill, 1602 North Eighteenth Street, Sweet Home, Linn County, OR

  17. SU4228472 Simpson's Neutrino and the Singular SeeSaw

    E-print Network

    Allen, Theodore J.

    SU­4228­472 FTUV/91­18 IFIC/91­15 April 1991 Simpson's Neutrino and the Singular See­Saw T. J­matrices'' which describe the generic singular see­saw model. The dependence on the hierarchy pa­ rameter is guided by the see­saw mechanism [15] in which two two­component fields for each generation are assumed

  18. Saw-type Lint Cleaner Damage by Machinery Components

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Saw-type lint cleaners are commonly used to improve the overall quality of ginned lint by removing non-lint content and less desirable short fibers; however saw-type lint cleaners discard a certain amount of good lint while removing foreign matter and short fiber from the good lint. The saw-type li...

  19. Microsystem packaging of an RF SAW correlator.

    SciTech Connect

    Palmer, David A.; Brocato, Robert Wesley; Studor, George F.

    2005-01-01

    An electrically programmable surface acoustic wave (SAW) correlator was recently completed from design through small scale production in support of low power space-based communications for NASA. Three different versions of this RF microsystem were built to satisfy design requirements and overcome packaging and system reliability related issues. Flip-chip packaging and conventional thick film hybrid assembly techniques are compared in the fabrication of this microsystem.

  20. Surface-acoustic-wave (SAW) flow sensor.

    PubMed

    Joshi, S G

    1991-01-01

    The use of a surface-acoustic-wave (SAW) device to measure the rate of gas flow is described. A SAW oscillator heated to a suitable temperature above ambient is placed in the path of a flowing gas. Convective cooling caused by the gas flow results in a change in the oscillator frequency. A 73-MHz oscillator fabricated on 128 degrees rotated Y-cut lithium niobate substrate and heated to 55 degrees C above ambient shows a frequency variation greater than 142 kHz for flow-rate variation from 0 to 1000 cm(3)/min. The output of the sensor can be calibrated to provide a measurement of volume flow rate, pressure differential across channel ports, or mass flow rate. High sensitivity, wide dynamic range, and direct digital output are among the attractive features of this sensor. Theoretical expressions for the sensitivity and response time of the sensor are derived. It is shown that by using ultrasonic Lamb waves, propagating in thin membranes, a flow sensor with faster response than a SAW sensor can be realized. PMID:18267569

  1. Surface-acoustic-wave (SAW) flow sensor

    NASA Astrophysics Data System (ADS)

    Joshi, Shrinivas G.

    1991-03-01

    The use of a surface-acoustic-wave (SAW) device to measure the rate of gas flow is described. A SAW oscillator heated to a suitable temperature above ambient is placed in the path of a flowing gas. Convective cooling caused by the gas flow results in a change in the oscillator frequency. A 73-MHz oscillator fabricated on 128 deg rotated Y-cut lithium niobate substrate and heated to 55 C above ambient shows a frequency variation greater than 142 kHz for flow-rate variation from 0 to 1000 cu cm/min. The output of the sensor can be calibrated to provide a measurement of volume flow rate, pressure differential across channel ports, or mass flow rate. High sensitivity, wide dynamic range, and direct digital output are among the attractive features of this sensor. Theoretical expressions for the sensitivity and response time of the sensor are derived. It is shown that by using ultrasonic Lamb waves propagating in thin membranes, a flow sensor with faster response than a SAW sensor can be realized.

  2. Sawing performance comparison of brazed and sintered diamond wires

    NASA Astrophysics Data System (ADS)

    Huang, Guoqin; Xu, Xipeng

    2013-03-01

    Great attention has been paid on fabricating diamond wire by using the brazing diamond because of its strong chemical bonding strength and controllability of grits distribution. Although several serving performances of brazed diamond wire have been reported, seldom do these studies refer to its process characteristics. Sawing performances of a brazed diamond wire are investigated and compared with those of a sintered diamond wire on a wire saw machine. The surface topographies of beads selected from the two wires are micro observed before sawing. The sawing tests are carried out in constant feed rate feeding(CFF) and constant normal force feeding(CNFF). In CFF test, sawing force, power, and the cut depths of positions on contact curve are measured. Then, coupled with the observations of beads topographies, sawing force and its ratio, relations of power against material removal rate, and contact curve linearity are compared and discussed. In CNFF test, the sawing rates of the two wires are investigated. The results indicate that the brazed wire performs with lower sawing force(less 16% of tangential force and 28% of normal force), more energy efficiency(nearly one-fifth of sawing power is saved), at a higher sawing rate (the rate is doubled) and with better contact curve linearity as compared with the sintered wire. This proposed research experimentally evaluates the sawing performances of brazed diamond wire from the aspect of process parameters, which can provide a basis for popularizing the brazed diamond wire.

  3. Noise reduction of a table saw

    NASA Astrophysics Data System (ADS)

    Carlson, John

    2002-05-01

    The National Institute for Occupational Safety and Health (NIOSH) is sponsoring a design project to address the noise levels that commonly exist at construction worksites. Through engineering control, the problem of noise emission from a table saw will be addressed. The noise emitting sources will be pinpointed using a sound pressure level meter. With this knowledge, the next step will be to reduce the sound pressure levels at the noise sources. This will be done by using noise reduction techniques such as insulation, and vibration dampening. The goal is to reduce the noise emission to a level between 85 and 90 dB(A).

  4. Thermal Imaging of Medical Saw Blades and Guides

    SciTech Connect

    Dinwiddie, Ralph Barton; Steffner, Thomas E

    2007-01-01

    Better Than New, LLC., has developed a surface treatment to reduce the friction and wear of orthopedic saw blades and guides. The medical saw blades were thermally imaged while sawing through fresh animal bone and an IR camera was used to measure the blade temperature as it exited the bone. The thermal performance of as-manufactured saw blades was compared to surface-treated blades, and a freshly used blade was used for temperature calibration purposes in order to account for any emissivity changes due to organic transfer layers. Thermal imaging indicates that the treated saw blades cut faster and cooler than untreated blades. In orthopedic surgery, saw guides are used to perfectly size the bone to accept a prosthesis. However, binding can occur between the blade and guide because of misalignment. This condition increases the saw blade temperature and may result in tissue damage. Both treated ad untreated saw guides were also studied. The treated saw guide operated at a significantly lower temperature than untreated guide. Saw blades and guides that operate at a cooler temperature are expected to reduce the amount of tissue damage (thermal necrosis) and may reduce the number of post-operative complications.

  5. A new surface acoustic wave (SAW) delay line sensor

    NASA Astrophysics Data System (ADS)

    Jha, Shashank S.; Yadava, R. D. S.

    2013-06-01

    We propose a new configuration for SAW chemical sensing. A polymer coated SAW delay line device provides the coupling for synchronization of two stable self-sustained limit cycle oscillators. The dependence of synchronization frequency on the SAW delay time has been made the basis for chemical sensing. The analysis has carried out under conditions of weak phase coupling [1]. The dependence of synchronization modes on coupling parameters is analyzed. The sensitivity of a synchronization branch for vapor sorption induced delay perturbations is analyzed. This analysis shows the possibility of realizing high performance SAW sensors by this approach.

  6. Building SAWE Capability as an ANSI Accredited Standards Developer

    NASA Technical Reports Server (NTRS)

    Cerro, Jeffrey A.; Davis, Ed; Peterson, Eric; Griffiths, William T.; Brooks, Andy; Stratton, Bonnie; Attar, Jose

    2014-01-01

    This paper presents a 2014 status of the Society of Allied Weight Engineers' process towards becoming an Accredited Standards Developer (ASD) under certification by the United States American National Standards Institute (ANSI). Included is material from the committee's 2013 International presentation, current status, and additional general background material. The document strives to serve as a reference point to assist SAWE Recommended Practice and Standards developers in negotiating United States Standards Strategy, international standards strategy, and the association of SAWE standards and recommended practices to those efforts. Required procedures for SAWE to develop and maintain Recommended Practices and ANSI/SAWE Standards are reviewed.

  7. Programmable SAW development :Sandia/NASA project final report.

    SciTech Connect

    Brocato, Robert Wesley

    2004-10-01

    This report describes a project to develop both fixed and programmable surface acoustic wave (SAW) correlators for use in a low power space communication network. This work was funded by NASA at Sandia National Laboratories for fiscal years 2004, 2003, and the final part of 2002. The role of Sandia was to develop the SAW correlator component, although additional work pertaining to use of the component in a system and system optimization was also done at Sandia. The potential of SAW correlator-based communication systems, the design and fabrication of SAW correlators, and general system utilization of those correlators are discussed here.

  8. [The morphological features of skin wounds inflicted by joinery hand saws designed for different types of sawing].

    PubMed

    Sarkisian, B A; Azarov, P A

    2014-01-01

    The objective of the present work was to study the morphological features of skin wounds inflicted by joinery hand saws designed for longitudinal, transverse, and mixed sawing. A total of 60 injuries to the thigh skin inflicted by the recurring and reciprocating saw movements were simulated. The hand saws had 5 mm high "sharp" and "blunt"-tipped teeth. The analysis of the morphological features of the wounds revealed differences in their length and depth, shape of edge cuts and defects, and the relief of the walls depending on the sawtooth sharpness and the mode of sawing. It is concluded that morphological features of the wounds may be used to determine the type of the saw, the sharpness of its teeth, the direction and frequency of its movements. PMID:25269171

  9. Impact of gin saw tooth design on textile processing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Toothed gin saws have been used to separate cotton fiber from the seed for over 200 years. There have been many saw tooth designs developed over the years. Most of these designs were developed by trial and error. A complete and scientific analysis of tooth design has never been done. It is not k...

  10. New developments for SAW channelization for mobile satellite payloads

    NASA Technical Reports Server (NTRS)

    Peach, R. C.; Mabson, P.

    1995-01-01

    The use of SAW technology in mobile communication payloads is becoming widely accepted by the industry since being pioneered by Inmarsat for its third generation of satellites. This paper presents new developments in this area, including broadband processors of the Inmarsat 3 type, and the use of SAW filters at L-band. It is demonstrated that SAW processors have considerable potential for increasing the capacity of future communications payloads, while allowing fully transparent operation without any restriction on traffic type or modulation format. In addition to the evolutionary development of Inmarsat type processors, new SAW applications have also emerged recently. Therefore, despite the rapid changes in the industry, it is predicted that SAW processing has a strong future in satellite communications.

  11. Wireless SAW sensors for surface and subsurface sensing applications

    NASA Astrophysics Data System (ADS)

    Stelzer, Andreas; Schimetta, Gernot; Reindl, Leonhard; Springer, Andreas; Weigel, Robert

    2001-11-01

    Surface acoustic wave (SAW) devices, used as filters or diplexers, are well established components in communications applications like in mobile handsets or television sets. The characteristics of SAW devices make them also well suitable for the application of wireless sensors or wireless identification tags. A great advantage of SAW sensors is their completely passive operation without the need for additional power supplies. SAW sensors can be designed to sense several physical or chemical quantities like temperature, pressure, stress, or gas concentration. During operation of the wireless sensor the energy delivered from an RF pulse sent by an interrogation unit is picked up by the antenna, stored in the surface acoustic wave, modified by the sensor effect and is finally transmitted back to the interrogation unit. In this paper the basic operating principles of SAW devices are reviewed and two applications, a state-of-the-art tire pressure sensor and a moisture sensor, are presented.

  12. Preliminary experiments on SAW based magnetization switching of nanomagnets

    NASA Astrophysics Data System (ADS)

    Sampath, Vimal; D'Souza, Noel; Bandyopadhyay, Supriyo; Atulasimha, Jayasimha

    2015-03-01

    Magnetization rotation in micron-sized ferromagnetic elements, using Surface Acoustic Waves (SAW), has been demonstrated experimentally while the use of SAW to lower the energy dissipation in switching of nanomagnets with spin transfer torque has been studied theoretically. Furthermore, SAW can be used to ``Bennett clock'' an array of nanomagnets in nanomagnetic logic without requiring lithographic contacts to individual nanomagnets. We report preliminary experiments on use of SAW to switch magnetostrictive Co nanomagnets grown on bulk 128 Y-cut lithium niobate. Switching is studied by imaging the nanomagnets' magnetic states with Magnetic Force Microscopy (MFM) before and after the SAW waves interact with them. Switching of single, isolated nanomagnets of various sizes, and dipole coupled nanomagnets implementing a Boolean NOT gate, is studied. This work is supported by the US National Science Foundation under the SHF-Small Grant CCF-1216614, CAREER Grant CCF-1253370, NEB 2020 Grant ECCS-1124714 and SRC under NRI Task 2203.001.

  13. Three-step approach for wafer sawing lane inspection

    NASA Astrophysics Data System (ADS)

    Wang, Jing-Wein; Wang, Chia-Nan; Chen, Wen-Yuan

    2009-11-01

    Wafer sawing performance must be closely monitored to ensure a satisfactory integrated circuits manufacturing yield. The inspection must allow the GO/NG decision to be fast and reliable, while also assuring that the training of the inspector is simple and not time consuming. The traditional neural-network approach to inspect images, while simple to implement, presents some disadvantages, including training efficiency and model effectiveness. Based on contour detection of the sawing lane, this work proposes a novel method combined with cross-center localization of sawing lanes, detection of sawing track, and four signatures to detect the abnormality of sawing effectively and timely. Our method does not need pretraining but runs faster and provides a better method with more effectiveness, higher flexibility, and immediate feedback to the sawing operation. An experiment using real data collected from an international semiconductor package factory is conducted to validate the performance of the proposed framework. The accurate acceptance rate and the accurate rejection rate are both 100%, while the false acceptance rate and false rejection rate are both zero as well. The results demonstrate that the proposed method is sound and useful for sawing inspection in industries.

  14. Development of Novel Atomization System Based on SAW Streaming

    NASA Astrophysics Data System (ADS)

    Chono, Katsumi; Shimizu, Norifumi; Matsui, Yoshikazu; Kondoh, Jun; Shiokawa, Showko

    2004-05-01

    In this paper, we describe a novel atomization system using surface acoustic wave (SAW) devices. The SAW radiates its energy into a liquid, if the liquid is loaded on the SAW propagating surface. The various liquid motions, such as vibration, flow and droplet formation, due to interaction between SAW and liquid are called SAW streaming. The liquid dynamics depends on the SAW input power. First, the relationships between input voltage to the SAW device and water dynamics are observed. For atomization, an input voltage larger than 30 VP-P is required. Second, a stable method of generating a mist is discussed. The thin liquid layer plays an important role in continuous mist generation. The fundamental properties, such as the angle and height of mist, are measured using a filter paper to keep a thin liquid layer on the surface. We also demonstrate the control of mist direction with an electrostatic field. Based on these fundamental experiments, a practical atomization system is designed and performed.

  15. Predictive force model for haptic feedback in bone sawing.

    PubMed

    James, Thomas P; Pearlman, John J; Saigal, Anil

    2013-11-01

    Bone sawing simulators with force feedback represent a cost effective means of training orthopedic surgeons in various surgical procedures, such as total knee arthroplasty. To develop a machine with accurate haptic feedback, giving a sensation of both cutting force and rate of material removal, algorithms are required to forecast bone sawing forces based on user input. Presently, studies on forces generated while machining bone are not representative of the high cutting speeds and low depths of cut common to the bone sawing process. The objective of this research was to quantify sawing forces in cortical bone as a function of blade speed and depth of cut. A fixture was developed to simulate linear bone sawing over a range of speeds comparable to surgical reciprocating and oscillating (sagittal) bone saws. A single saw blade tooth was isolated and used to create a slotted cut in bovine cortical bone. Over a range in linear sawing speed from 1700 to 7000 mm/s, a t-test (?=0.05) revealed there was no statistically significant effect of blade speed on either cutting or thrust force. However, an increase in depth of cut from 2 to 10 ?m resulted in a 30% increase in thrust force, while cutting force remained constant. The increase in thrust force with depth of cut was relatively linear, R(2)=0.80. Using a two factor, two level design of experiments approach, regression equations were developed to relate sawing forces to changes in blade speed and depth of cut. These equations can be used to predict forces in a haptic feedback model. PMID:23806417

  16. [A reciprocating saw for micro-surgery (author's transl)].

    PubMed

    Feldmann, H

    1977-09-01

    A reciprocating saw for osteoplastic microsurgery of the ear is presented. An electromagnetic oscillator of a common electric razor, used as motor, drives the saw with 100 oscillations per second. The amplitude of the vibrations can be adjusted by a special device within the range of 0.5 to 3 mm. The saw blades are 0.2 mm thick and not set. They perform very smooth straight cuts of 0.2 to 0.3 mm width and can easily be applied in the narrow operative field of the middle ear. PMID:143575

  17. ISS Asset Tracking Using SAW RFID Technology

    NASA Technical Reports Server (NTRS)

    Schellhase, Amy; Powers, Annie

    2004-01-01

    A team at the NASA Johnson Space Center (JSC) is undergoing final preparations to test Surface Acoustic Wave (SAW) Radio Frequency Identification (RFID) technology to track assets aboard the International Space Station (ISS). Currently, almost 10,000 U.S. items onboard the ISS are tracked within a database maintained by both the JSC ground teams and crew onboard the ISS. This barcode-based inventory management system has successfully tracked the location of 97% of the items onboard, but its accuracy is dependant on the crew to report hardware movements, taking valuable time away from science and other activities. With the addition of future modules, the volume of inventory to be tracked is expected to increase significantly. The first test of RFID technology on ISS, which will be conducted by the Expedition 16 crew later this year, will evaluate the ability of RFID technology to track consumable items. These consumables, which include office supplies and clothing, are regularly supplied to ISS and can be tagged on the ground. Automation will eliminate line-of-sight auditing requirements, directly saving crew time. This first step in automating an inventory tracking system will pave the way for future uses of RFID for inventory tracking in space. Not only are there immediate benefits for ISS applications, it is a crucial step to ensure efficient logistics support for future vehicles and exploration missions where resupplies are not readily available. Following a successful initial test, the team plans to execute additional tests for new technology, expanded operations concepts, and increased automation.

  18. Imprinted laminate wafer-level packaging for SAW ID-tags and SAW delay line sensors.

    PubMed

    Kuypers, Jan H; Tanaka, Shuji; Esashi, Masayoshi

    2011-02-01

    We have developed a wafer-level packaging solution for surface acoustic wave devices using imprinted dry film resist (DFR). The packaging process involves the preparation of an imprinted dry film resist that is aligned and laminated to the device wafer and requires one additional lithography step to define the package outline. Two commercial dry film solutions, SU-8 and TMMF, have been evaluated. Compared with traditional ceramic packages, no detectable RF parasitics are introduced by this packaging process. At the same time, the miniature package dimensions allow for wafer-level probing. The packaging process has the great advantage that the cavity formation does not require any sacrificial layer and no liquids, and therefore prevents contamination or stiction of the packaged device. This non-hermetic packaging process is ideal for passive antenna modules using polymer technology for low-cost SAW identification (ID)-tags or lidding in low-temperature cofired ceramic (LTCC) antenna substrates for high-performance wireless sensors. This technique is also applicable to SAW filters and duplexers for module integration in cellular phones using flip-chip mounting and hermetic overcoating. PMID:21342826

  19. 5. View of north elevation, including saw dust collector and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. View of north elevation, including saw dust collector and brick addition, looking south east. - General Dynamics Corporation Shipyard, Joiner & Sheet Metal Shops, 97 East Howard Street, Quincy, Norfolk County, MA

  20. 21. William E. Barrett, Photographer, August 1975. EDGER SAWS FOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. William E. Barrett, Photographer, August 1975. EDGER SAWS FOR RIPPING BOARD TO VARIOUS WIDTHS. BLADES VISIBLE BEHIND ROLLERS. - Meadow River Lumber Company, Highway 60, Rainelle, Greenbrier County, WV

  1. 19. William E. Barrett, Photographer, August 1975. LOWER BAND SAW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. William E. Barrett, Photographer, August 1975. LOWER BAND SAW PULLEYS OF RIGHT-HAND MILL. DRIVE PULLEY IN BELOW TENSION PULLEY. - Meadow River Lumber Company, Highway 60, Rainelle, Greenbrier County, WV

  2. Determining See-Saw Parameters from Weak Scale Measurements?

    E-print Network

    Sacha Davidson; Alejandro Ibarra

    2001-09-18

    The see-saw mechanism is a very attractive explanation for small neutrino masses, parametrized at the GUT scale by the right-handed Majorana mass matrix, ${\\cal M}$, and the neutrino Yukawa matrix, ${\\bf Y_\

  3. DNA Barcode Authentication of Saw Palmetto Herbal Dietary Supplements

    PubMed Central

    Little, Damon P.; Jeanson, Marc L.

    2013-01-01

    Herbal dietary supplements made from saw palmetto (Serenoa repens; Arecaceae) fruit are commonly consumed to ameliorate benign prostate hyperplasia. A novel DNA mini–barcode assay to accurately identify [specificity = 1.00 (95% confidence interval = 0.74–1.00); sensitivity = 1.00 (95% confidence interval = 0.66–1.00); n = 31] saw palmetto dietary supplements was designed from a DNA barcode reference library created for this purpose. The mini–barcodes were used to estimate the frequency of mislabeled saw palmetto herbal dietary supplements on the market in the United States of America. Of the 37 supplements examined, amplifiable DNA could be extracted from 34 (92%). Mini–barcode analysis of these supplements demonstrated that 29 (85%) contain saw palmetto and that 2 (6%) supplements contain related species that cannot be legally sold as herbal dietary supplements in the United States of America. The identity of 3 (9%) supplements could not be conclusively determined. PMID:24343362

  4. Chapter 9.06 Disco Automatic Dicing Saw

    E-print Network

    Healy, Kevin Edward

    Dicing Saw operation Manual (available in the office). 4.0 Definitions & Process Terminology 4.1 Cut Mode spindle index ranges from 0 mm to 210 mm in 0.0001 mm increments. 2.0 Manual Scope 2.1 This manual describes the standard setup and use of the DAD3240 dicing saw. 3.0 Applicable Documents 3.1 Automatic Disco

  5. Investigation of SAW frequency filters with diffraction gratings

    NASA Astrophysics Data System (ADS)

    Grankin, I. M.; Nelin, E. A.

    1984-04-01

    A theoretical and experimental study is made of a method for enhancing the selectivity of SAW frequency filters by means of acoustic diffraction gratings. It is shown that the frequency-response characteristics of these gratings and the SAW field distribution at the grating output are related by the Fourier transformation. The high efficiency of the proposed selectivity-enhancement method is validated theoretically and confirmed experimentally.

  6. See-saw nystagmus and brainstem infarction: MRI findings

    NASA Technical Reports Server (NTRS)

    Kanter, D. S.; Ruff, R. L.; Leigh, R. J.; Modic, M.

    1987-01-01

    A patient with see-saw nystagmus had a lesion localized by Magnetic Resonance Imaging (MRI) to the paramedian ventral midbrain with involvement of the right interstitial nucleus of Cajal. This the first MRI study of see-saw nystagmus associated with a presumed brainstem vascular event. Our findings support animal and human studies suggesting that dysfunction of the interstitial nucleus of Cajal or its connections is central in this disorder.

  7. Effect of critical dimension variation on SAW correlator energy.

    SciTech Connect

    Skinner, Jack L.

    2005-04-01

    The effect of critical dimension (CD) variation and metallization ratio on the efficiency of energy conversion of a surface acoustic wave (SAW) correlator is examined. We find that a 10% variation in the width of finger electrodes predicts only a 1% decrease in the efficiency of energy conversion. Furthermore, our model predicts that a metallization ratio of 0.74 represents an optimum value for energy extraction from the SAW by the interdigitated transducer (IDT).

  8. The Type-II Singular See-Saw Mechanism

    E-print Network

    Kristian. L. McDonald; B. H. J. McKellar

    2007-05-09

    The singular see-saw mechanism is a variation of the see-saw mechanism whereby the right-chiral neutrino Majorana mass matrix is singular. Previous works employing the singular see-saw mechanism have assumed a vanishing left-chiral Majorana mass matrix. We study the neutrino spectrum obtained under a singular see-saw mechanism when the left-chiral neutrinos possess a non-zero Majorana mass matrix. We refer to this as the type-II singular see-saw mechanism. The resulting neutrino spectrum is found to be sensitive to the hierarchy of the Dirac and Majorana mass scales used and we explore the phenomenological consequences of the candidate hierarchies. The compatibility of the resulting spectra with the body of neutrino oscillation data is discussed. It is found that neutrino mass matrices with this structure result in 3+1 or 2+2 neutrino spectra, making it unlikely that this mass matrix structure is realized in nature. If the left-chiral Majorana mass matrix is also singular we show that a type-II singular see-saw mechanism can realize a spectrum of one active-sterile pseudo-Dirac neutrino in conjunction with two active Majorana neutrinos effectively decoupled from the sterile sector. This realizes a scheme discussed in the literature in relation to astrophysical neutrino fluxes.

  9. Notes on SAW Tag Interrogation Techniques

    NASA Technical Reports Server (NTRS)

    Barton, Richard J.

    2010-01-01

    We consider the problem of interrogating a single SAW RFID tag with a known ID and known range in the presence of multiple interfering tags under the following assumptions: (1) The RF propagation environment is well approximated as a simple delay channel with geometric power-decay constant alpha >/= 2. (2) The interfering tag IDs are unknown but well approximated as independent, identically distributed random samples from a probability distribution of tag ID waveforms with known second-order properties, and the tag of interest is drawn independently from the same distribution. (3) The ranges of the interfering tags are unknown but well approximated as independent, identically distributed realizations of a random variable rho with a known probability distribution f(sub rho) , and the tag ranges are independent of the tag ID waveforms. In particular, we model the tag waveforms as random impulse responses from a wide-sense-stationary, uncorrelated-scattering (WSSUS) fading channel with known bandwidth and scattering function. A brief discussion of the properties of such channels and the notation used to describe them in this document is given in the Appendix. Under these assumptions, we derive the expression for the output signal-to-noise ratio (SNR) for an arbitrary combination of transmitted interrogation signal and linear receiver filter. Based on this expression, we derive the optimal interrogator configuration (i.e., transmitted signal/receiver filter combination) in the two extreme noise/interference regimes, i.e., noise-limited and interference-limited, under the additional assumption that the coherence bandwidth of the tags is much smaller than the total tag bandwidth. Finally, we evaluate the performance of both optimal interrogators over a broad range of operating scenarios using both numerical simulation based on the assumed model and Monte Carlo simulation based on a small sample of measured tag waveforms. The performance evaluation results not only provide guidelines for proper interrogator design, but also provide some insight on the validity of the assumed signal model. It should be noted that the assumption that the impulse response of the tag of interest is known precisely implies that the temperature and range of the tag are also known precisely, which is generally not the case in practice. However, analyzing interrogator performance under this simplifying assumption is much more straightforward and still provides a great deal of insight into the nature of the problem.

  10. Diamond Wire Saw for Precision Machining of Laser Target Components

    SciTech Connect

    Bono, M J; Bennett, D W

    2005-08-08

    The fabrication of precision laser targets requires a wide variety of specialized mesoscale manufacturing techniques. The diamond wire saw developed in this study provides the capability to precisely section meso-scale workpieces mounted on the assembly stations used by the Target Fabrication Group. This new capability greatly simplifies the fabrication of many types of targets and reduces the time and cost required to build the targets. A variety of materials are used to fabricate targets, including metals, plastics with custom designed chemical formulas, and aerogels of various densities. The materials are usually provided in the form of small pieces or cast rods that must be machined to the required shape. Many of these materials, such as metals and some plastics, can be trimmed using a parting tool on a diamond turning machine. However, other materials, such as aerogels and brittle materials, cannot be adequately cut with a parting tool. In addition, the geometry of the parts often requires that the workpieces be held in a special assembly station, which excludes the use of a parting tool. In the past, these materials were sectioned using a small, handheld coping saw that used a diamond-impregnated wire as a blade. This miniature coping saw was effective, but it required several hours to cut through certain materials. Furthermore, the saw was guided by hand and often caused significant damage to fragile aerogels. To solve these problems, the diamond wire saw shown in Figure 1 was developed. The diamond wire saw is designed to machine through materials that are mounted in the Target Fabrication Group's benchtop assembly stations. These assembly stations are the primary means of aligning and assembling target components, and there is often a need to machine materials while they are mounted in the assembly stations. Unfortunately, commercially available saws are designed for very different applications and are far too large to be used with the assembly stations. Therefore, a custom diamond wire saw was designed and constructed. The diamond wire saw cuts through workpieces using a continuous loop of diamond-impregnated wire of length 840 mm. The wire loop runs around several idler pulleys and is driven by a simple geared DC motor that rotates at 17 rpm. The linear speed of the wire is 107 inches/minute. The saw is oriented at an angle of 20{sup o} from horizontal, so the operator can view the wire through the cutout at the front end of the saw. When looking through a microscope or camera with a horizontal line of sight, the operator can clearly see the wire as it cuts through the workpiece, as shown in the right side of Figure 1. The saw is mounted on a two-axis stage that allows the operator to align the wire with the workpiece. To cut through the workpiece, the operator drives the wire through the workpiece by turning the feed micrometer. An image of the interior of the diamond wire saw appears in Figure 2. This picture was taken after removing the protective cover plate from the saw.

  11. Tip stabilizer for a chain saw. Final report

    SciTech Connect

    Morabit, V.D.

    1993-09-10

    Prior to receiving the grant, Utilitip was faced with an idea that truly worked, however only a very limited line of component parts would fit various types of chain saws on the market. It also suffered from a severe problem when engaged in the ground of soil penetrating the saw chain area, thus eliminating one of the major benefits of keeping the chain sharp. Consequently, the grant funding was directed towards extending the tooling capabilities to produce parts for a much wider variety of chain saws that are on the market, and further by developing an effective flexible soil shield to prevent abrasive soil entry into the saw chain. Utilitip was able to complete a full set of design for a wide variety of large and small chain saws. This incorporated a design and fabrication of a small Utilitip, as well as a small anti-kickback device. In addition, tooling was also further developed for the large Utilitip and the large anti-kickback device. Accordingly, multiple tools are available for all combinations, as well as back-up provisions. Utilitip, Inc. invented a special, flexible attachment to be glued and/or molded to the tip guard. The soil shield prevents abrasive soil from coming into the chain area. In addition, it allows a flexible arrangement to allow the chain saw to be released from brush without binding. Otherwise, a larger, rigid soil shield would hold or restrict the saw in heavy brush. The rubber shield will flex out of the say and reduce, if not eliminate, this harmful binding.

  12. Vibration syndrome in Forestry Commission chain saw operators

    PubMed Central

    Taylor, W.; Pearson, J.; Kell, R. L.; Keighley, G. D.

    1971-01-01

    Taylor, W., Pearson, J., Kell, R. L., and Keighley, G. D. (1971). Brit. J. industr. Med., 28, 83-89. Vibration syndrome in Forestry Commission chain saw operators. A preliminary investigation has been made into the prevalence of the vibration syndrome in the employees of the Forestry Commission (Britain). A questionnaire covered 20 randomly selected employees for each of 40 forests chosen at random, giving a total sample of 800 out of 9 600 employees. Of the 756 employees still with the Forestry Commission, 732 responded (97%). The analyses were confined to the 711 male employees, of whom 142 were chain saw operators. In this number, the prevalence of the vibration syndrome was 44% whereas in men who did not handle the chain saw the prevalence was significantly lower at 18% (0·005 level of significance). A regional difference was found. South England showed the highest rate at 69% compared with North England at 31% and Scotland at 33%. An increase in prevalence with years of chain saw usage was found, starting at around two years with a marked increase (73%) at over eight years. In part, this effect explains the regional differences. Men with the syndrome were significantly more affected by chilling at work, during rest periods, and while sheltering from bad weather, with blanching of the fingers (89%) most affected by the weather, followed by sensory loss (84%). During the survey vibration levels were measured on 18 chain saws. The major vibration component from each saw fell within the 125 Hz octave band and the vibration levels considerably exceeded the criterion of Axelsson (1968). In 16 of the saws the amplitudes were greater on the lower (trigger) handle. PMID:5543631

  13. SAW atomization application on inhaled pulmonary drug delivery

    NASA Astrophysics Data System (ADS)

    Qi, Aisha; Friend, James; Yeo, Leslie

    2008-12-01

    Pulmonary drug delivery transports the drug formulations directly to the respiratory tract in the form of inhaled particles or droplets. Because of the direct target treatment, it has significant advantages in the treatment of respiratory diseases, for example asthma. However, it is difficult to produce monodispersed particles/droplets in the 1-10 micron range, which is necessary for deposition in the targeted lung area or lower respiratory airways, in a controllable fashion. We demonstrate the use of surface acoustic waves (SAWs) as an efficient method for the generation of monodispersed micron dimension aerosols for the treatment of asthma. SAWs are ten nanometer order amplitude electroacoustic waves generated by applying an oscillating electric field to an interdigital transducer patterned on a piezoelectric substrate. The acoustic energy in the waves induces atomization of the working fluid, which contains a model drug, albuterol. Laser diffraction techniques employed to characterize the aerosols revealed mean diameter of the aerosol was around 3-4 ?m. Parallel experiments employing a one-stage (glass) twin impinger as a lung model demonstrated a nearly 80% of atomized drug aerosol was deposited in the lung. The aerosol size distribution is relatively independent of the SAW frequency, which is consistent with our predictive scaling theory which accounts for the dominant balance between viscous and capillary stresses. Moreover, only 1-3 W powers consumption of SAW atomization suggests that the SAW atomizer can be miniaturized into dimensions commensurate with portable consumer devices.

  14. Wide vacuum pressure range monitoring by Pirani SAW sensor.

    PubMed

    Nicolay, Pascal; Elmazria, Omar; Sarry, Frederic; Bouvot, Laurent; Kambara, Hisanori; Singh, Kanwar J; Alnot, Patrick

    2010-03-01

    A new kind of surface acoustic wave (SAW) sensor has been developed to measure sub-atmospheric pressure below 100 mtorr with accuracy better than 0.1 mtorr. It provides an efficient measuring solution in the pressure range inaccessible in past by conventional diaphragm-based SAW sensors. Indeed, because of the small bending force in lower pressure and limited sensitivity, diaphragm-based SAW sensors are only suited to monitor relatively high pressure with a precision hardly better than 0.5 torr. To reach precision level better than 1 mtorr at sub-atmospheric pressure for vacuum technology applications, a radically different SAW-based solution is necessary. Our device aims to measure sub-atmospheric pressure less than 100 mtorr with a threshold resolution better than 0.1 mtorr. The concept is similar to the one used by Pirani pressure gauges. However, it is claimed that a heated and suspended SAW device should have better sensitivity. A theoretical model based on the basic concepts of gas kinetic theory and thermodynamics is presented. The validity of the model is checked by comparison between theoretical and experimental results. PMID:20211788

  15. Exit chipping in ID sawing of silicon crystals

    NASA Technical Reports Server (NTRS)

    Dyer, L. D.

    1982-01-01

    The processes involved in exit chipping which may occur in the internal diameter diamond sawing of silicon crystals were examined. An interpretation of chipping observations is given in terms of crack propagation as acted upon by the sawing stresses. Since the exit chips are roughly parallel to saw marks, the general locus of the crack must be determined by contact stresses although the exact locus depends on already existing subfractures located in the kerf region which are caused by more than one abrasive particle. The crack starts at either edge since these are weak areas in flexure. In the more extensive "saw fracture", the fracture plane often changes part-way across the slice to be other than parallel to the saw mark because the speed of the crack accelerates beyond the speed of the blade travel; i.e., outstrips the advance of the contact stress field. The influences of various external factors on the opening of the crack are divided into two types: factors that wedge the crack apart and those that bend the slice away from the crystal. From a consideration of these factors, conditions for minimizing exit chipping are defined.

  16. High-Temperature SAW Wireless Strain Sensor with Langasite.

    PubMed

    Shu, Lin; Peng, Bin; Yang, Zhengbing; Wang, Rui; Deng, Senyang; Liu, Xingzhao

    2015-01-01

    Two Surface acoustic wave (SAW) resonators were fabricated on langasite substrates with Euler angle of (0°, 138.5°, 117°) and (0°, 138.5°, 27°). A dipole antenna was bonded to the prepared SAW resonator to form a wireless sensor. The characteristics of the SAW sensors were measured by wireless frequency domain interrogation methods from 20 °C to 600 °C. Different temperature behaviors of the sensors were observed. Strain sensing was achieved using a cantilever configuration. The sensors were measured under applied strain from 20 °C to 500 °C. The shift of the resonance frequency contributed merely by strain is extracted from the combined effects of temperature and strain. Both the strain factors of the two SAW sensors increase with rising ambient temperature, and the SAW sensor deposited on (0°, 138.5°, 117°) cut is more sensitive to applied strain. The measurement errors of the two sensors are also discussed. The relative errors of the two sensors are between 0.63% and 2.09%. Even at 500 °C, the hysteresis errors of the two sensors are less than 5%. PMID:26569255

  17. Efficient transport of droplet sandwiched between saw-tooth plates.

    PubMed

    Wang, Liya; Wu, Hengan; Wang, Fengchao

    2016-01-15

    The transport of droplet sandwiched between smooth and saw-tooth plates was investigated using molecular dynamics method. The repeated opening and closing of the plates result in sequential stretching and squeezing of the droplet, which provide the driving force. The asymmetrical saw tooth obstructs the backward motion of the droplet, and gives rise to a net forward displacement of the droplet in every opening and closing cycle. This unidirectional motion facilitates the efficient droplet transport, which is referred to as the ratchet-like effect in this work. Our simulations also reveal that the influence of the surface wettability on the droplet transport is different for saw-tooth and smooth plates. Droplet transport efficiency exhibits monotonic decrease with the increase of the solid-liquid interactions for saw-tooth plates. While for smooth plates, unidirectional droplet movement was only observed for certain solid-liquid interactions. Taken together these simulation results and theoretical analysis, we demonstrate that hydrophobic saw-tooth plates can improve the transport efficiency significantly. These findings not only enhance our understanding of the droplet transport from atomistic scale, but also are beneficial to practical applications in designing of micro- and nano-fluidic systems. PMID:26473277

  18. Effect of lubricant environment on saw damage in silicon wafers

    NASA Technical Reports Server (NTRS)

    Kuan, T. S.; Shih, K. K.; Vanvechten, J. A.; Westdorp, W. A.

    1982-01-01

    The chemomechanical effect of lubricant environments on the inner diameter (ID) sawing induced surface damage in Si wafers was tested for four different lubricants: water, dielectric oil, and two commercial cutting solutions. The effects of applying different potential on Si crystals during the sawing were also tested. It is indicated that the number and depth of surface damage are sensitive to the chemical nature of the saw lubricant. It is determined that the lubricants that are good catalysts for breaking Si bonds can dampen the out of plane blade vibration more effectively and produce less surface damage. Correlations between the applied potential and the depth of damage in the dielectric oil and one of the commercial cutting solutions and possible mechanisms involved are discussed.

  19. Sawing hardwoods in five tropical countries. Forest Service research note

    SciTech Connect

    Loehnertz, S.P.; Vazquez Cooz, I.; Guerrero, J.

    1994-09-01

    In this study, hardwood sawing technology was identified in five tropical countries: Ghana, Brazil, Venezuela, Indonesia, and Malaysia. The density of wood and presence of silica make it a challenge to saw many tropical hardwoods. The handsaw is the most commonly used machine and is employed in many sizes and configurations. Sawblade parameters and operating procedures vary according to the nature of the species being sawn and are influenced as much by local custom as technical knowledge of the process. The most commonly reported problems include poor saw maintenance, lack of trained personnel, obsolete equipment, and inadequate sawtooth geometry and wear resistance. Some problems can be addressed by technology transfer, others must be addressed by research.

  20. SAW chemical sensor arrays using new thin-film materials

    SciTech Connect

    Ricco, A.J.; Xu, Chuanjing; Crooks, R.M.; Allred, R.E.

    1994-05-01

    We have used two classes of materials, self-assembled monolayers (SAMs) and plasma-grafted films (PGFs), as new chemically sensitive layers for an array of 97-MHz surface acoustic wave (SAW) delay-line-based devices. Responses of these materials to each of 14 different analytes, representing the classes of saturated alkane, aromatic hydrocarbon, chlorinated hydrocarbon, alcohol, ketone, organophosphonate, and water, have been evaluated using our six-SAW device array. Results reveal a qualitative ``chemical orthogonality`` of the films that is very promising for pattern recognition analysis.

  1. SAW dispersion measurements for ultrasonic characterization of surface-

    E-print Network

    Nagy, Peter B.

    -treated metals. KEYWORDS: Ultrasonic Surface Waves, Spectroscopy, Nondestructive Testing, Shot Peening. #12SAW dispersion measurements for ultrasonic characterization of surface- treated metals Alberto Ruiz complicated by the accompanying surface roughness and cold work. A high-precision laser-ultrasonic technique

  2. Wafer Slicing and Wire Saw Manufacturing Technology I. Kao (PI)

    E-print Network

    Kao, Imin

    Wafer Slicing and Wire Saw Manufacturing Technology I. Kao (PI) and V. Prasad, J. Li, M. Bhagavat to cut very thin wafers from large diameter crystalline ingots of semiconductor materials, has emerged as a leading technology for wafer production in semiconductor and photovoltaic industry. Nevertheless, the wire

  3. Surface Acoustic Wave (SAW) Resonators for Monitoring Conditioning Film Formation

    PubMed Central

    Hohmann, Siegfried; Kögel, Svea; Brunner, Yvonne; Schmieg, Barbara; Ewald, Christina; Kirschhöfer, Frank; Brenner-Weiß, Gerald; Länge, Kerstin

    2015-01-01

    We propose surface acoustic wave (SAW) resonators as a complementary tool for conditioning film monitoring. Conditioning films are formed by adsorption of inorganic and organic substances on a substrate the moment this substrate comes into contact with a liquid phase. In the case of implant insertion, for instance, initial protein adsorption is required to start wound healing, but it will also trigger immune reactions leading to inflammatory responses. The control of the initial protein adsorption would allow to promote the healing process and to suppress adverse immune reactions. Methods to investigate these adsorption processes are available, but it remains difficult to translate measurement results into actual protein binding events. Biosensor transducers allow user-friendly investigation of protein adsorption on different surfaces. The combination of several transduction principles leads to complementary results, allowing a more comprehensive characterization of the adsorbing layer. We introduce SAW resonators as a novel complementary tool for time-resolved conditioning film monitoring. SAW resonators were coated with polymers. The adsorption of the plasma proteins human serum albumin (HSA) and fibrinogen onto the polymer-coated surfaces were monitored. Frequency results were compared with quartz crystal microbalance (QCM) sensor measurements, which confirmed the suitability of the SAW resonators for this application. PMID:26007735

  4. INTRODUCTION TO MACHINING 1.4 METAL CUTTING BAND SAWS

    E-print Network

    Sun, Yu

    in standardized forms and sizes, such as round, rectangular or square bar stock or in the form of large sheets (plates). Bar stock normally is available in lengths of up to 4 [m], sheets in dimensions up to 1.2 [m] x done using band saws. Sheets are pre-cut using flame or plasma cutting machines or shearing machines

  5. Overview of Cannery Building, note the saw tooth monitors with ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Overview of Cannery Building, note the saw tooth monitors with glazing and with corrugated fiberglass and screens, view facing north - Kahului Cannery, Plant No. 28, Cannery Building and Dryer House/Feed Storage Building, 120 Kane Street, Kahului, Maui County, HI

  6. A Novel Wireless and Temperature-Compensated SAW Vibration Sensor

    PubMed Central

    Wang, Wen; Xue, Xufeng; Huang, Yangqing; Liu, Xinlu

    2014-01-01

    A novel wireless and passive surface acoustic wave (SAW) based temperature-compensated vibration sensor utilizing a flexible Y-cut quartz cantilever beam with a relatively substantial proof mass and two one-port resonators is developed. One resonator acts as the sensing device adjacent to the clamped end for maximum strain sensitivity, and the other one is used as the reference located on clamped end for temperature compensation for vibration sensor through the differential approach. Vibration directed to the proof mass flex the cantilever, inducing relative changes in the acoustic propagation characteristics of the SAW travelling along the sensing device, and generated output signal varies in frequency as a function of vibration. A theoretical mode using the Rayleigh method was established to determine the optimal dimensions of the cantilever beam. Coupling of Modes (COM) model was used to extract the optimal design parameters of the SAW devices prior to fabrication. The performance of the developed SAW sensor attached to an antenna towards applied vibration was evaluated wirelessly by using the precise vibration table, programmable incubator chamber, and reader unit. High vibration sensitivity of ?10.4 kHz/g, good temperature stability, and excellent linearity were observed in the wireless measurements. PMID:25372617

  7. 28. MODIFIED CHAIN SAW FOR CUTTING ROCK CORES; BRUNTON COMPASS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. MODIFIED CHAIN SAW FOR CUTTING ROCK CORES; BRUNTON COMPASS STAND FOR DETERMINING CORE'S FIELD ORIENTATION; INSECTICIDE DISPENSER MODIFIED TO LUBRICATE CORE DRILLING PROCESS. - U.S. Geological Survey, Rock Magnetics Laboratory, 345 Middlefield Road, Menlo Park, San Mateo County, CA

  8. 222. View of the Mabry Grist and saw mill before ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    222. View of the Mabry Grist and saw mill before the NPS dredged the pond and razed the Mabry House in 1947, replacing it with the Matthews Cabin in 1956-57. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  9. 77 FR 8751 - Table Saw Blade Contact Injuries; Reopening of the Comment Period

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-15

    ...CPSC-2011-0074] Table Saw Blade Contact Injuries; Reopening of the Comment Period...injury associated with table saw blade contact, regulatory alternatives, other possible...including any personal identifiers, contact information, or other personal...

  10. 76 FR 75504 - Table Saw Blade Contact Injuries; Notice of Extension of Time for Comments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-02

    ...CPSC-2011-0074] Table Saw Blade Contact Injuries; Notice of Extension of Time...injury associated with table saw blade contact, regulatory alternatives, other possible...including any personal identifiers, contact information, or other personal...

  11. Roughening and smoothing behavior of Al/Zr multilayers grown on flat and saw-tooth substrates

    E-print Network

    Voronov, Dmitriy

    2012-01-01

    the observed decay of the PSD of saw-tooth substrates duringthe decay of PSD peaks during deposition on a saw-toothdecay assuming both n=2 and n=4 process presenting during the smoothing of the saw-tooth

  12. Impact of a Saw-type Lint Cleaner's Operation on Fiber Quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The saw-type lint cleaner is the primary method of cleaning lint at gins. Two one-year studies were conducted to examine fiber quality properties produced by a saw-type lint cleaner in response to variations in: feed rate, saw speed, combing ratio, variety and lint moisture. One hairy-leaf and two...

  13. Wire-sawing defects on multicrystalline silicon wafers grown by a directional solidification method

    NASA Astrophysics Data System (ADS)

    Du, Guoping; Chen, Nan; Rossetto, Pietro

    2008-05-01

    In the industrial production of multicrystalline silicon (mc-Si) wafers used for solar cells, linear wire-sawing defects are sometimes generated on the surfaces of mc-Si wafers. The presence of such wire-sawing defects makes the mc-Si wafers unsuitable for the fabrication of solar cells. In this work, we first studied the nature of the linear wire-sawing defects on the mc-Si wafers, and then investigated how these wire-sawing defects were generated during the wire-sawing process. It has been found that the linear wire-sawing defects are sawing ridges and ditches on the wafer surfaces, and direct evidence has suggested that they are generated due to the presence of SiC particles embedded within mc-Si. The SiC particles form an obstacle to the movement of the sawing wire during the wire-sawing process, and the sawing wire tends to climb over the SiC obstacle, resulting in the generation of the wire-sawing defects. A model for the generation of the wire-sawing defects has been proposed. This work will be of much practical interest to the commercial mc-Si wafer production communities for solar cells.

  14. STUDY OF A WIRE BRUSH GRID BAR REPLACEMENT FOR SAW-TYPE LINT CLEANERS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Saw type lint cleaners are commonly used to improve the overall quality of ginned lint through the removal of non-lint material and short fibers. A standard saw type lint cleaner is made up of several components: the feed works, saws, and grid bars. Slover Manufacturing (Lamesa, TX) has designed an...

  15. Hydrogen-Bond Basic Siloxane Phosphonate Polymers for Surface Acoustic Wave (Saw) Sensors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A surface acoustic wave (SAW) sensor coated with a novel hydrogen-bond basic siloxane phosphonate SAW polymer gave excellent initial response and long-term performance when tested against phenol vapor and compared with polyethyleneimine (PEI), a conventional hydrogent-bond basic SAW polymer....

  16. Passive hybrid sensing tag with flexible substrate saw device

    DOEpatents

    Skinner, Jack L.; Chu, Eric Y.; Ho, Harvey

    2012-12-25

    The integration of surface acoustic wave (SAW) filters, microfabricated transmission lines, and sensors onto polymer substrates in order to enable a passive wireless sensor platform is described herein. Incident microwave pulses on an integrated antenna are converted to an acoustic wave via a SAW filter and transmitted to an impedance based sensor, which for this work is a photodiode. Changes in the sensor state induce a corresponding change in the impedance of the sensor resulting in a reflectance profile. Data collected at a calibrated receiver is used to infer the state of the sensor. Based on this principal, light levels were passively and wirelessly demonstrated to be sensed at distances of up to about 12 feet.

  17. Isothermal measurement and thermal desorption using SAW devices

    NASA Astrophysics Data System (ADS)

    Martin, S. J.; Ricco, A. J.; Zipperian, T. E.

    The conventional implementation of surface acoustic wave (SAW) devices is departed from as gas sensors to describe how they may be used to measure adsorption isotherms and to perform thermal desorption spectroscopy. Adsorption isotherms are measurements, made at constant temperature, of surface coverage as a function of gas or vapor partial pressure for the species of interest. It was shown that by incorporating a heater as an integral part of a SAW device, a sensor can be constructed which is capable of measuring thermal desorption spectra. A greater spread in the temperatures at which molecules are desorbed, and thus greater discrimination between species, could be obtained by using coatings which form stronger chemical bonds rather than relying on physisorption.

  18. BAW and SAW sensors for in situ analysis

    NASA Astrophysics Data System (ADS)

    Sherrit, Stewart; Bao, Xiaoqi; Bar-Cohen, Yoseph; Chang, Zensheu

    2003-07-01

    In-situ planetary sample analysis is a major goal in current and future NASA exploration missions. In general in-situ analysis experiments are designed to investigate chemical, biological or geological markers or properties to determine the complex history of the body being studied or for use as a pre-screening measurement to increase the scientific value of samples selected for sample return. In order to expand the number of applicable sensor schemes and the available capability an investigation into piezoelectric bulk acoustic wave (BAW) and surface acoustic wave (SAW) resonators has been initiated with emphasis on applications to future NASA missions. In general, BAW and SAW sensors can be configured to directly measure mass, acoustic impedance, density and elastic property changes. Indirectly they can be designed to measure or monitor pressure, temperature, dew/melting point, curing, adsorption/desorption, and viscosity and be configured with the appropriate reaction layers as chemical sensors or as Immunosensors. The various models used to describe these sensors will be presented and the measurand sensitivity and importance of cross sensitivities will be discussed. Recent advances in passive wireless RF interrogated SAW technology has increased the scope of these sensor systems to remote sensing (10m) and to applications which may have been deemed previously inaccessible. Examples include SAW stress sensors buried in large structures that once assembled are inaccessible for measurement that can be interrogated with wireless RF signals to determine the health of the structure. In addition, this technology has recently been coupled with other sensor technology allowing for an expansion of the possibilities for remote sensing. On the basis of the cost, range, versatility and ease of array fabrication of these sensors offer significant potential for future NASA missions.

  19. SAW parameters on Y-cut langasite structured materials.

    PubMed

    Puccio, Derek; Malocha, Donald C; Saldanha, Nancy; da Cunha, Mauricio Pereira

    2007-09-01

    This paper presents results and investigations of several new, man-made piezoelectric single crystal, Czochralski-grown substrate materials for surface acoustic waves (SAW) applications. These materials, langanite (LGN), langatate (LGT), Sr3TaGa3Si2O14 (STGS), Sr3NbGa3Si2O14 (SNGS), Ca3TaGa3Si2O14 (CTGS), and Ca3NbGa3Si2O14 (CNGS), have the same structure as langasite (LGS) and are of the same crystal class as quartz. These compounds are denser than quartz, resulting in lower phase velocities. They also have higher coupling. Unlike quartz and lithium niobate, there is no degradation of material properties below the material melting points resulting in the possibility of extreme high-temperature operation (> 1000 degrees C). This paper gives a summary of extracted SAW material parameters for various propagation angles on Y-cut substrates of the six materials. Parameters included are electromechanical coupling, phase velocity, transducer capacitance, metal strip reflectivity, and temperature coefficient of frequency. Using previously published fundamental material constants, extracted parameters are compared with predictions for LGT and LGN. In addition, power flow angle and fractional frequency curvature data are reported for propagation angles on CTGS and CNGS Y-cut substrates that exhibit temperature compensation near room temperature. Detailed descriptions of the SAW parameter extraction techniques are given. A discussion of the results is provided, including a comparison of extracted parameters and an overview of possible SAW applications. PMID:17941393

  20. Technology towards a SAW based phononic crystal sensor

    NASA Astrophysics Data System (ADS)

    Schmidt, Marc-Peter; Oseev, Aleksandr; Lucklum, Ralf; Hirsch, Soeren

    2015-05-01

    Phononic crystals (PnC) with a specifically designed defect have been recently introduced as novel sensor platform. Those sensors feature a band gap covering the typical input span of the measurand as well as a narrow transmission peak within the band gap where the frequency of maximum transmission is governed by the measurand. This innovative approach has been applied for determination of compounds in liquids [1]. Improvement of sensitivity requires higher probing frequencies around 100 MHz and above. In this range surface acoustic wave devices (SAW) provide a promising basis for PnC based microsensors [2]. The respective feature size of the PnC SAW sensor has dimensions in the range of 100 ?m and below. Whereas those dimensions are state of the art for common MEMS materials, etching of holes and cavities in piezoelectric materials having an aspect ratio diameter/depth is challenging. In this contribution we describe an improved technological process to manufacture considerably deep and uniform phononic crystal structures inside of SAW substrates.

  1. Orthogonal frequency coding for SAW tagging and sensors.

    PubMed

    Puccio, Derek; Malocha, Donald C; Saldanha, Nancy; Gallagher, Daniel R; Hines, Jacqueline H

    2006-02-01

    Surface acoustic wave (SAW)-based sensors can offer wireless, passive operation in numerous environments, and various device embodiments are used for retrieval of the sensed data information. Single sensor systems typically can use a single carrier frequency and a simple device embodiment because tagging is not required. In a multisensor environment, it is necessary to both identify the sensor and retrieve the sensed information. This paper presents the concept of orthogonal frequency coding (OFC) for applications to SAW sensor technology. The OFC offers all advantages inherent to spread spectrum communications, including enhanced processing gain and lower interrogation power spectral density (PSD). It is shown that the time ambiguity in the OFC compressed pulse is significantly reduced as compared with a single frequency tag having the same code length, and additional coding can be added using a pseudo-noise (PN) sequence. The OFC approach is general and should be applicable to many differing SAW sensors for temperature, pressure, liquid, gases, etc. Device embodiments are shown, and a potential transceiver is described. Measured device results are presented and compared with coupling of modes (COM) model predictions to demonstrate performance. Devices then are used in computer simulations of the proposed transceiver design, and the results of an OFC sensor system are discussed. PMID:16529112

  2. Characterization of graphene oxide nanofilms obtained by the SAW atomization

    NASA Astrophysics Data System (ADS)

    Balachova, O. V.; Balashov, S. M.; Kubota, L. T.; Timm, R. A.; Nascimento, P. H.; Pavani Filho, A.; Moshkalev, S.

    2015-03-01

    Due to its ability to absorb water molecules, graphene oxide (GO) is considered a promising material for sensitive coatings in fast surface acoustic wave (SAW) humidity sensors. In this work, we characterize GO films obtained by the SAW atomization technique. It is shown that the atomized submicroliter droplets of aqueous suspension of GO can be deposited onto the surface of Si, LiNbO3 or quartz substrates forming discrete or continuous films of nanometer thickness. The deposited films were examined using AFM and electron microscopy. We discuss the dependence of thickness and structure of the obtained GO films on the parameters of deposition: the number of atomized droplets, a volume of the initial droplet, a distance between the atomizer and the sample, etc. To evaluate the adsorption characteristics of the obtained GO films, we used them as sensitive coatings of the SAW humidity sensors. We found that the adsorption characteristics of the GO films are determined by fast adsorption on the surface of GO sheets and slow adsorption, attributed to limited penetration of water molecules between the sheets, and depend on the number of deposited layers.

  3. 1st Order Modeling of a SAW Delay Line using MathCAD(Registered)

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Atkinson, Gary M.

    2007-01-01

    To aid in the development of SAW sensors for Integrated Vehicle Health Monitoring applications, a first order model of a SAW Delay line has been created using MathCadA. The model implements the Impulse Response method to calculate the frequency response, impedance, and insertion loss. This paper presents the model and the results from the model for a SAW delay line design. Integrated Vehicle Health Monitoring (IVHM) of aerospace vehicles requires rugged sensors having reduced volume, mass, and power that can be used to measure a variety of phenomena. Wireless systems are preferred when retro-fitting sensors onto existing vehicles [1]. Surface Acoustic Wave (SAW) devices are capable of sensing: temperature, pressure, strain, chemical species, mass loading, acceleration, and shear stress. SAW technology is low cost, rugged, lightweight, and extremely low power. Passive wireless sensors have been developed using SAW technology. For these reasons new SAW sensors are being investigated for aerospace applications.

  4. If you saw Tom Cruise smiling like Jack Nicolson, you would still recognize the person as Tom Cruise. However, if you saw

    E-print Network

    If you saw Tom Cruise smiling like Jack Nicolson, you would still recognize the person as Tom Cruise. However, if you saw a face that looked like a mixture between the shapes of Tom Cruises' and Jack¨lthoff Could you recognize Jack Nicolson or Tom Cruise by their smiles? Would you realize, if Tom Cruise smiled

  5. Can LHC Test the See-Saw Mechanism?

    E-print Network

    Joern Kersten

    2007-10-19

    We discuss the prospects for detecting right-handed neutrinos which are introduced in the see-saw mechanism at future colliders. This requires a very accurate cancellation between contributions from different right-handed neutrinos to the light neutrino mass matrix. We search for possible symmetries behind this cancellation and find that they have to include lepton number conservation. Light neutrino masses can be generated as a result of small symmetry-breaking perturbations. The impact of these perturbations on LHC physics is negligible, so that the mechanism of neutrino mass generation and LHC physics are decoupled in general. In constrained cases, accelerator observables and neutrino masses and mixings can be correlated.

  6. Novel SH-SAW gas sensor based on graphene

    NASA Astrophysics Data System (ADS)

    Nikolaou, I.; Hallil, H.; Deligeorgis, G.; Conedera, V.; Garcia, H.; Dejous, C.; Rebière, D.

    2015-05-01

    In this article, a novel gas sensor platform has been studied. Several layers of graphene have been deposited on a SH-SAW, as a sensitive layer. Innovative methods of graphene solutions have been prepared in order to explore gas sensing applications. The real time detection measurement of the coated sensor under ethanol and humidity is presented. The adsorption of vapors leads to a frequency shift of 10.5 kHz and 22.7 kHz, at exposure of 100 ppm of ethanol and 6.22% of Relative Humidity, respectively. The experiments have been realized at room temperature; rapid response and recovery time were observed.

  7. Silicon saw-tooth refractive lens for high-energy x-rays made using a diamond saw.

    SciTech Connect

    Said, A. H.; Shastri, S. D.; X-Ray Science Division

    2010-01-01

    Silicon is a material well suited for refractive lenses operating at high X-ray energies (>50 keV), particularly if implemented in a single-crystal form to minimize small-angle scattering. A single-crystal silicon saw-tooth refractive lens, fabricated by a dicing process using a thin diamond wheel, was tested with 115 keV X-rays, giving an ideal 17 {mu}m line focus width in a long focal length, 2:1 ratio demagnification geometry, with a source-to-focus distance of 58.5 m. The fabrication is simple, using resources typically available at any synchrotron facility's optics shop.

  8. Palestine Saw-scaled Vipers hunt disadvantaged avian migrants.

    PubMed

    Yosef, Reuven; Zduniak, Piotr

    2015-11-01

    The selection of an ambush-cum-foraging site and proper prey are indispensable for maintaining an adequate energy intake by sit-and-wait predators to optimize survival and future fitness. This is important for snakes, where an ambush site has suitable ambience. We studied the foraging strategy of the Palestine Saw-scaled Viper (Echis coloratus) at an avian migratory stopover site. Following initial observations, we hypothesized that vipers are able to discern the body mass of a perched bird and hunt accordingly. We implemented an experiment where vipers chose between four groups of migratory Blackcaps with different body mass. Prey choice by vipers of both age classes was not random and adults focused on Blackcaps with the lightest body mass. Juveniles displayed a variability of prey choice but selected mainly birds from the lightest categories. We concluded that Saw-scaled Vipers hunt prey based on thermal cues; juveniles practice on different prey groups prior to perfecting their foraging techniques i.e., hunting is a learned process; and that they prefer birds with the lowest body mass. The last because Blackcaps, when on migration, save energy by entering a state of deep torpor in which they sacrifice their vigilance capabilities. PMID:26319368

  9. Modelling Sawing of Metal Tubes Through FEM Simulation

    NASA Astrophysics Data System (ADS)

    Bort, C. M. Giorgio; Bosetti, P.; Bruschi, S.

    2011-05-01

    The paper presents the development of a numerical model of the sawing process of AISI 304 thin tubes, which is cut through a circular blade with alternating roughing and finishing teeth. The numerical simulation environment is the three-dimensional FEM software Deform™ v.10.1. The teeth actual trajectories were determined by a blade kinematics analysis developed in Matlab™. Due to the manufacturing rolling steps and subsequent welding stage, the tube material is characterized by a gradient of properties along its thickness. Consequently, a simplified cutting test was set up and carried out in order to identify the values of relevant material parameters to be used in the numerical model. The dedicated test was the Orthogonal Tube Cutting test (OTC), which was performed on an instrumented lathe. The proposed numerical model was validated by comparing numerical results and experimental data obtained from sawing tests carried out on an industrial machine. The following outputs were compared: the cutting force, the chip thickness, and the chip contact area.

  10. Silicon sawing waste treatment by electrophoresis and gravitational settling.

    PubMed

    Tsai, Tzu-Hsuan

    2011-05-15

    In silicon wafer manufacturing for solar cells, a great amount of hazardous sawing waste with tiny Si particles is produced, resulting in serious environmental problems. Recycling Si and abrasives from the waste is regarded as an effective solution. Based on the view of recycling, Al(2)O(3) might be good abrasives for cutting Si ingot due to its larger density and higher isoelectric point than SiC. This study reports the separation of Si/SiC and Si/Al(2)O(3) mixtures by electrophoresis and gravitational settling. At pH 9, nearly uncharged Al(2)O(3) settled quickly and the negatively charged Si moved toward the anode, leading to an obvious Si distribution on the cell bottom. The experimental results show the separation performance of Si and Al(2)O(3) at pH 9 was better than at pH 2.5, and the performance was higher than that between Si and SiC. The minimum and maximum Al(2)O(3) contents remaining in Si/Al(2)O(3) mixture were 9 wt% and 90 wt% after applying 1 V/cm for 24h at pH 9. The recovered material with high Si content can be considered as a new Si source for solar cell, and the abrasives can be reused in the sawing process. PMID:21402439

  11. A Passive Wireless Multi-Sensor SAW Technology Device and System Perspectives

    PubMed Central

    Malocha, Donald C.; Gallagher, Mark; Fisher, Brian; Humphries, James; Gallagher, Daniel; Kozlovski, Nikolai

    2013-01-01

    This paper will discuss a SAW passive, wireless multi-sensor system under development by our group for the past several years. The device focus is on orthogonal frequency coded (OFC) SAW sensors, which use both frequency diversity and pulse position reflectors to encode the device ID and will be briefly contrasted to other embodiments. A synchronous correlator transceiver is used for the hardware and post processing and correlation techniques of the received signal to extract the sensor information will be presented. Critical device and system parameters addressed include encoding, operational range, SAW device parameters, post-processing, and antenna-SAW device integration. A fully developed 915 MHz OFC SAW multi-sensor system is used to show experimental results. The system is based on a software radio approach that provides great flexibility for future enhancements and diverse sensor applications. Several different sensor types using the OFC SAW platform are shown. PMID:23666124

  12. Impact of micromechanical parameters on wire sawing: a 3D discrete element analysis

    NASA Astrophysics Data System (ADS)

    Nassauer, B.; Kuna, M.

    2015-05-01

    Wire sawing is one of the most prominent technologies for producing solar wafers. In the following paper a numerical model for the simulation of the wire sawing process at microlevel using the discrete element method is presented. The abrasive particles are represented by convex polyhedra. Based on the contact forces on the ingot, local material removal rates are calculated. These local material removal rates are then used to update the shape of the ingot in a stepwise simulation. The model allows for detailed analysis of the influence of different parameters on the micromechanical processes during wire sawing. In particular the influence of wire speed, lapping pressure, particle concentration, particle size, particle shape and debris on the sawing process is investigated. In a post-processing macroscopic process characteristics like kerf width, depth of surface cracks or sawing rate are calculated. Thus, the processes at the microlevel are related to the macroscopic process characteristics, which are of interest when applying wire sawing in practice.

  13. Mixed Modeling of a SAW Delay Line Using VHDL-AMS

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Atkinson, Gary M.

    2006-01-01

    To aid in the development of SAW sensors for aerospace applications we have created a model of a SAW Delay line using VHDL. The model implements the Impulse Response method to calculate the frequency response, impedance, and insertion loss. The model includes optimization for the number of finger pairs in the IDTs and for the aperture height. This paper presents the model and the results from the model for a SAW delay line design.

  14. An Improved Performance Frequency Estimation Algorithm for Passive Wireless SAW Resonant Sensors

    PubMed Central

    Liu, Boquan; Zhang, Chenrui; Ji, Xiaojun; Chen, Jing; Han, Tao

    2014-01-01

    Passive wireless surface acoustic wave (SAW) resonant sensors are suitable for applications in harsh environments. The traditional SAW resonant sensor system requires, however, Fourier transformation (FT) which has a resolution restriction and decreases the accuracy. In order to improve the accuracy and resolution of the measurement, the singular value decomposition (SVD)-based frequency estimation algorithm is applied for wireless SAW resonant sensor responses, which is a combination of a single tone undamped and damped sinusoid signal with the same frequency. Compared with the FT algorithm, the accuracy and the resolution of the method used in the self-developed wireless SAW resonant sensor system are validated. PMID:25429410

  15. Cold response of digital arteries in chain saw operators

    PubMed Central

    Olsen, N; Nielsen, S L; Voss, P

    1982-01-01

    ABSTRACT In a study of vibration-induced white finger (VWF) 39 chain saw operators, being representative of 365 lumberjacks according to a completed questionnaire, underwent clinical investigation. In a medical interview 13 of the 39 had VWF and 26 were without finger symptoms. In the subjects with VWF both hands were equally affected, the third and fourth finger most frequently; the thumbs were always normal. A cold provocation test, measuring the finger systolic blood pressure with a cuff technique during combined body cooling and finger cooling to 30, 15, and 6°C, was applied to the 39 chain saw operators and to 20 age-matched outdoor workers who had not used vibrating hand tools. The finger most often showing Raynaud's phenomenon was cold provoked, and a non-affected finger was used as a reference. The systolic pressure gradient measured at 30°C from the upper arm to the cooled finger was increased in the chain sawyers most severely affected by VWF compared with the control group and with the chain sawyers without VWF (p <0·02). Raynaud's phenomenon was verified by digital arterial closure (zero pressure in the finger) at 15 or 6°C in 12 of 13 chain sawyers having anamnestic and clinical evidence of VWF. Chain sawyers without VWF had an increased digital arterial response to cold at 15 and 6°C compared with the control group (p <0·05) and had a decreased cold response compared with chain sawyers with VWF (p <0·05). In chain sawyers without VWF 13 subjects with an exposure period of 10-23 years had an increased cold response at 6°C compared with 13 subjects with an exposure period of one to three years (p <0·05). Only one of 38 chain saws did not exceed the exposure limit proposed by the International Standardisation Organisation. The results of the present study indicate that vibrations induce hyperresponsiveness to cold in the exposed arteries, even in chain sawyers without finger symptoms. The exposure to vibration therefore should be reduced to eliminate this damage. The presented cold provocation test may be used to diagnose Raynaud's phenomenon and to disclose an abnormal digital arterial cold response before subjective symptoms have appeared. Images PMID:7066225

  16. Conformal Neutrinos: an Alternative to the See-saw Mechanism

    E-print Network

    Gero von Gersdorff; Mariano Quiros

    2009-02-19

    We analyze a scenario where the right-handed neutrinos make part of a strongly coupled conformal field theory and acquire an anomalous dimension \\gammaconformal invariance. We derive an upper bound on \\gamma from loop-induced flavor changing neutral currents. Neutrino Yukawa couplings can be sizable at electroweak scales and therefore the invisible decay of the Higgs in the neutrino channel can be comparable to the c\\bar c and \\tau\\bar\\tau modes and predict interesting Higgs phenomenology. If lepton number is violated in the conformal theory an irrelevant Majorana mass operator for right-handed neutrinos appears for \\gamma>1/2 giving rise to an inverse see-saw mechanism. In this case light sterile neutrinos do appear and neutrino oscillation experiments are able to probe our model.

  17. Investigation of crossed SAW fields by scanning acoustic force microscopy.

    PubMed

    Behme, G; Hesjedal, T

    2001-07-01

    We used multimode scanning acoustic force microscopy (SAFM) for studying noncollinearly propagating Rayleigh and Love wave fields. By analyzing torsion and bending movement of SAFM cantilever, normal and in-plane wave oscillation components are accessible. The SAFM principle is the down-conversion of surface oscillations into cantilever vibrations caused by the nonlinearity of the tip-sample interaction. Through mixing of complementary oscillation components, phase velocities of crossed Rayleigh waves on GaAs and crossed Rayleigh and Love waves on the layered system SiO2/ST-cut quartz were obtained simultaneously. Now, it is possible to investigate elastic properties of submicron areas through multimode SAFM measurements. Finally, we present mixing experiments of four SAWs on GaAs and discuss the various influences on the measured SAFM amplitude and phase contrast. PMID:11477772

  18. Corrosion inhibitors for water-base slurry in multiblade sawing

    NASA Technical Reports Server (NTRS)

    Chen, C. P.; Odonnell, T. P.

    1982-01-01

    The use of a water-base slurry instead of the standard PC oil vehicle was proposed for multiblade sawing (MBS) silicon wafering technology. Potential cost savings were considerable; however, significant failures of high-carbon steel blades were observed in limited tests using a water-based slurry during silicon wafering. Failures were attributed to stress corrosion. A specially designed fatigue test of 1095 steel blades in distilled water with various corrosion inhibitor solutions was used to determine the feasibility of using corrosion inhibitors in water-base MBS wafering. Fatigue tests indicate that several corrosion inhibitors have significant potential for use in a water-base MBS operation. Blade samples tested in these specific corrosion-inhibitor solutions exhibited considerably greater lifetime than those blades tested in PC oil.

  19. Field portable detection of VOCs using a SAW/GC system

    SciTech Connect

    Staples, E.J.

    1995-12-31

    This paper describes research on a fast gas chromatography (GC) vapor analysis system which uses a new type of surface acoustic wave (SAW) detector technology to characterize organic compounds in soils and groundwater. Field testing of GC/SAW was performed at the Savannah River plant.

  20. Separation of biological cells in a microfluidic device using surface acoustic waves (SAWs)

    NASA Astrophysics Data System (ADS)

    Ai, Ye; Marrone, Babetta L.

    2014-03-01

    In this study, a surface acoustic wave (SAW)-based microfluidic device has been developed to separate heterogeneous particle or cell mixtures in a continuous flow using acoustophoresis. The microfluidic device is comprised of two components, a SAW transducer and a microfluidic channel made of polydimethylsiloxane (PDMS). The SAW transducer was fabricated by patterning two pairs of interdigital electrodes on a lithium niobate (LiNbO3) piezoelectric substrate. When exciting the SAW transducer by AC signals, a standing SAW is generated along the cross-section of the channel. Solid particles immersed in the standing SAW field are accordingly pushed to the pressure node arising from the acoustic radiation force acting on the particles, referring to the acoustic particle-focusing phenomenon. Acoustic radiation force highly depends on the particle properties, resulting in different acoustic responses for different types of cells. A numerical model, coupling the piezoelectric effect in the solid substrate and acoustic pressure in the fluid, was developed to provide a better understanding of SAW-based particle manipulation. Separation of two types of fluorescent particles has been demonstrated using the developed SAW-based microfluidic device. An efficient separation of E. coli bacteria from peripheral blood mononuclear cell (PBMC) samples has also been successfully achieved. The purity of separated E. coli bacteria and separated PBMCs were over 95% and 91%, respectively, obtained by a flow cytometric analysis. The developed microfluidic device can efficiently separate E. coli bacteria from biological samples, which has potential applications in biomedical analysis and clinical diagnosis.

  1. 78 FR 31897 - Agency Information Collection Activities; Proposed Collection; Comment Request; CPSC Table Saw...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-28

    ... (ANPR) for table saws, under the Consumer Product Safety Act (CPSA), 15 U.S.C. 2051-2084. (76 FR 62678... injuries. 76 FR 62683. Currently, the CPSC does not know how consumers are using the new modular blade... on a survey of table saw users to determine the effectiveness of modular blade guards. DATES:...

  2. Cutting crime: the analysis of the "uniqueness" of saw marks on bone.

    PubMed

    Saville, P A; Hainsworth, S V; Rutty, G N

    2007-09-01

    Witness marks produced on bone by the use of saws have traditionally been examined using stereomicroscopy. The marks are typically found on the kerf wall or floor and give important information about the implement that made them. This paper describes a new approach to the analysis of witness marks left on kerf walls and floors from crimes involving dismemberment. Previously, two types of marks have been identified: deep furrows formed during the pull stroke and fine striations formed on the push stroke. These types of striation allow the class of saw to be identified, but not an individual saw. With the advent of environmental scanning electron microscopy (ESEM), insulating materials can now be examined without the need for conductive coatings to be applied. This allows materials to be examined at higher magnifications than those available with stereomicroscopy. Here we report on a new, third type of striation that is visible at higher magnifications on ESEM images. These striations are formed from the imperfections on the cutting teeth of saws and give real possibilities of uniquely identifying whether or not a particular saw was used to cause the mark. In blind trials conducted on sawing of nylon 6.6, different individual saws could be successfully identified even if different people used the saw. We discuss ways in which these results can be extended to bone and how this may assist in the investigation of the act of dismemberment. PMID:17021897

  3. Finite Element Modelling of the Sawing of DC Cast AA2024 Aluminium Alloy Slabs

    NASA Astrophysics Data System (ADS)

    Drezet, J.-M.; Ludwig, O.; Heinrich, B.

    2007-04-01

    In the semi-continuous casting of large cross-section rolling sheet ingots of high-strength aluminum alloys (2xxx and 7xxx series), the control of the residual (internal) stresses generated by the non-uniform cooling becomes a necessity. These stresses must be relieved by a thermal treatment before the head and foot of the ingot can be cut. Otherwise, the saw can be caught owing to compressive stresses or cut parts may be ejected thus injuring people or damaging equipment. These high added-value ingots need to be produced in secure conditions. Moreover, a better control of the sawing procedure could allow the suppression of the thermal treatment and therefore save time and energy. By studying the stress build-up during casting and the stress relief during sawing, key parameters for the control and optimization of the processing steps, can be derived. To do so, the direct chill (DC) casting of the AA2024 alloy is modeled with ABAQUS 6.5 with special attention to the thermo-mechanical properties of the alloy. The sawing operation is then simulated by removing mesh elements so as to reproduce the progression of the saw in the ingot. Preliminary results showing the stress relief during sawing accompanied by the risk of saw blocking due to compression or initiating a crack ahead of the saw, are analyzed with an approach based on the rate of strain energy release.

  4. Real-time SAW measurements of NVR in cleanroom and in microenvironment

    SciTech Connect

    Liang, A.Y.; McIntyre, D.C.; Lujan, R.D.; Thornberg, S.M.; Bender, S.F.A.

    1994-05-01

    Using a real-time, Surface Acoustic Wave (SAW) sensing instrument supplied by Femtometrics, we have measured organic contamination, or nonvolatile residues (NVR), in both a cleanroom and a microenvironment. To demonstrate the {open_quotes}real-time{close_quotes} NVR detectability and sensitivity of the SAW instrument, controlled contamination experiments with photoresist material were also conducted. In addition, two cleaning methods for removing contamination from used sensors have been evaluated. One technique uses the on-board temperature varying capability of the SAW instrument, while the other technique utilizes a uv-ozone cleaner for the sensor cleaning. Preliminary results from SAW measurements in the cleanroom and in a microenvironment and tests to evaluate sensor cleaning techniques are presented in this report. A concluding summary with an assessment of the current SAW instrument and potential future applications for this technology is also presented.

  5. Calibration of the QCM/SAW Cascade Impactor for Measurement of Ozone in the Stratosphere

    NASA Technical Reports Server (NTRS)

    Wright, Cassandra K.; Sims, S. C.; Peterson, C. B.; Morris, V. R.

    1997-01-01

    The Quartz Crystal Microbalance Surface Acoustic Wave (QCM/SAW) cascade impactor collects size-fractionated distributions of aerosols on a series of 10 MHz quartz crystals and employs SAW devices coated with chemical sensors for gas detection. Presently, we are calibrating the ER-2 certified QCM/SAW cascade impactor in the laboratory for the detection of ozone. Experiments have been performed to characterize the QCM and SAW mass loading, saturation limits, mass frequency relationships, and sensitivity. We are also characterizing sampling efficiency by measuring the loss of ozone on different materials. There are parallel experiments underway to measure the variations in the sensitivity and response of the QCM/SAW crystals as a function of temperature and pressure. Results of the work to date will be shown.

  6. 76 FR 62678 - Table Saw Blade Contact Injuries; Advance Notice of Proposed Rulemaking; Request for Comments and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-11

    ...CPSC-2011-0074] Table Saw Blade Contact Injuries; Advance Notice of Proposed...injury associated with table saw blade contact, the regulatory alternatives discussed...including any personal identifiers, contact information, or other personal...

  7. Method and apparatus for improved wire saw slurry

    DOEpatents

    Costantini, Michael A. (Hudson, NH); Talbott, Jonathan A. (Amherst, NH); Chandra, Mohan (Merrimack, NH); Prasad, Vishwanath (East Setauket, NY); Caster, Allison (Nashua, NH); Gupta, Kedar P. (Merrimack, NH); Leyvraz, Philippe (Nashua, NH)

    2000-09-05

    A slurry recycle process for use in free-abrasive machining operations such as for wire saws used in wafer slicing of ingots, where the used slurry is separated into kerf-rich and abrasive-rich components, and the abrasive-rich component is reconstituted into a makeup slurry. During the process, the average particle size of the makeup slurry is controlled by monitoring the condition of the kerf and abrasive components and making necessary adjustments to the separating force and dwell time of the separator apparatus. Related pre-separator and post separator treatments, and feedback of one or the other separator slurry output components for mixing with incoming used slurry and recirculation through the separator, provide further effectiveness and additional control points in the process. The kerf-rich component is eventually or continually removed; the abrasive-rich component is reconstituted into a makeup slurry with a controlled, average particle size such that the products of the free-abrasive machining method using the recycled slurry process of the invention are of consistent high quality with less TTV deviation from cycle to cycle for a prolonged period or series of machining operations.

  8. Wireless telemetry system for a SAW based microvalve

    NASA Astrophysics Data System (ADS)

    Tikka, Ajay C.; Al-Sarawi, Said F.; Jamali, Behnam; Abbott, Derek

    2008-12-01

    Inductively coupled RF telemetry is an optimal method for both power supply and data transmission in long term artificial implants due to small size, high reliability, and extended life span of the device. In this research, we propose the use of the same technique for secure remote interrogation and powering of a human implantable, Surface Acoustic Wave (SAW) correlation based, passive microvalve. This is carried out by interrogating the microvalve with a Barker sequence encoded BPSK signal. In this paper we present the development of a FEM model for the derivation of the induced voltage on a miniature (2.5×2.5×1 mm), inductively coupled, biocompatible spiral antenna/coil, interrogated by a 7.5×7.5×0.2 cm spiral antenna/coil in the near field. The amount of power transferred at a 30-160 MHz range was derived using the S21 coupling response when the two antennas are separated by a human body simulant of 5 cm depth. Furthermore, the effect of varying magnetic coupling on the induced voltage, due to the misorientation of coils/antennas is analysed.

  9. A radiation detector design mitigating problems related to sawed edges

    NASA Astrophysics Data System (ADS)

    Aurola, A.; Marochkin, V.; Tuuva, T.

    2014-12-01

    In pixelated silicon radiation detectors that are utilized for the detection of UV, visible, and in particular Near Infra-Red (NIR) light it is desirable to utilize a relatively thick fully depleted Back-Side Illuminated (BSI) detector design providing 100% Fill Factor (FF), low Cross-Talk (CT), and high Quantum Efficiency (QE). The optimal thickness of such detectors is typically less than 300?m and above 40?m and thus it is more or less mandatory to thin the detector wafer from the backside after the front side of the detector has been processed and before a conductive layer is formed on the backside. A TAIKO thinning process is optimal for such a thickness range since neither a support substrate on the front side nor lithographic steps on the backside are required. The conductive backside layer should, however, be homogenous throughout the wafer and it should be biased from the front side of the detector. In order to provide good QE for blue and UV light the conductive backside layer should be of opposite doping type than the substrate. The problem with a homogeneous backside layer being of opposite doping type than the substrate is that a lot of leakage current is typically generated at the sawed chip edges, which may increase the dark noise and the power consumption. These problems are substantially mitigated with a proposed detector edge arrangement which 2D simulation results are presented in this paper.

  10. Hybrid Surface Acoustic Wave- Electrohydrodynamic Atomization (SAW-EHDA) For the Development of Functional Thin Films

    PubMed Central

    Choi, Kyung Hyun; Kim, Hyun Bum; Ali, Kamran; Sajid, Memoon; Uddin Siddiqui, Ghayas; Chang, Dong Eui; Kim, Hyung Chan; Ko, Jeong Beom; Dang, Hyun Woo; Doh, Yang Hoi

    2015-01-01

    Conventional surface acoustic wave - electrostatic deposition (SAW-ED) technology is struggling to compete with other thin film fabrication technologies because of its limitation in atomizing high density solutions or solutions with strong inter-particle bonding that requires very high frequency (100?MHz) and power. In this study, a hybrid surface acoustic wave - electrohydrodynamic atomization (SAW-EHDA) system has been introduced to overcome this problem by integrating EHDA with SAW to achieve the deposition of different types of conductive inks at lower frequency (19.8?MHZ) and power. Three materials, Poly [2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene] (MEH-PPV), Zinc Oxide (ZnO), and Poly(3, 4-ethylenedioxythiophene):Polystyrene Sulfonate (PEDOT:PSS) have been successfully deposited as thin films through the hybrid SAW-EHDA. The films showed good morphological, chemical, electrical, and optical characteristics. To further evaluate the characteristics of deposited films, a humidity sensor was fabricated with active layer of PEDOT:PSS deposited using the SAW-EHDA system. The response of sensor was outstanding and much better when compared to similar sensors fabricated using other manufacturing techniques. The results of the device and the films’ characteristics suggest that the hybrid SAW-EHDA technology has high potential to efficiently produce wide variety of thin films and thus predict its promising future in certain areas of printed electronics. PMID:26478189

  11. Hybrid Surface Acoustic Wave- Electrohydrodynamic Atomization (SAW-EHDA) For the Development of Functional Thin Films

    NASA Astrophysics Data System (ADS)

    Choi, Kyung Hyun; Kim, Hyun Bum; Ali, Kamran; Sajid, Memoon; Uddin Siddiqui, Ghayas; Chang, Dong Eui; Kim, Hyung Chan; Ko, Jeong Beom; Dang, Hyun Woo; Doh, Yang Hoi

    2015-10-01

    Conventional surface acoustic wave - electrostatic deposition (SAW-ED) technology is struggling to compete with other thin film fabrication technologies because of its limitation in atomizing high density solutions or solutions with strong inter-particle bonding that requires very high frequency (100?MHz) and power. In this study, a hybrid surface acoustic wave - electrohydrodynamic atomization (SAW-EHDA) system has been introduced to overcome this problem by integrating EHDA with SAW to achieve the deposition of different types of conductive inks at lower frequency (19.8?MHZ) and power. Three materials, Poly [2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene] (MEH-PPV), Zinc Oxide (ZnO), and Poly(3, 4-ethylenedioxythiophene):Polystyrene Sulfonate (PEDOT:PSS) have been successfully deposited as thin films through the hybrid SAW-EHDA. The films showed good morphological, chemical, electrical, and optical characteristics. To further evaluate the characteristics of deposited films, a humidity sensor was fabricated with active layer of PEDOT:PSS deposited using the SAW-EHDA system. The response of sensor was outstanding and much better when compared to similar sensors fabricated using other manufacturing techniques. The results of the device and the films’ characteristics suggest that the hybrid SAW-EHDA technology has high potential to efficiently produce wide variety of thin films and thus predict its promising future in certain areas of printed electronics.

  12. Comparative ecology of the Flammulated Owl and Northern Saw-whet Owl during fall migration

    USGS Publications Warehouse

    Stock, S.L.; Heglund, P.J.; Kaltenecker, G.S.; Carlisle, J.D.; Leppert, L.

    2006-01-01

    We compared the migration ecology of two owl species that exhibit different migration strategies: the Flammulated Owl (Otus flammeolus) and the Northern Saw-whet Owl (Aegolius acadicus). During fall 1999-2004, we captured 117 Flammulated Owls and 1433 Northern Saw-whet Owls in the southern Boise Mountains of southwestern Idaho. These owl species exhibited contrasting seasonal timing and body condition. Flammulated Owl captures peaked in mid-September and Northern Saw-whet Owl captures peaked in early to mid-October. Flammulated Owls displayed greater body condition than Northern Saw-whet Owls and increasing condition scores during the season, whereas Northern Saw-whet Owls had no apparent seasonal condition patterns. Based on seasonal timing of captures, both species showed unimodal movement patterns characteristic of fall migrants. However, in 1999 both species' capture rates were at least double those in other years of this study. Flammulated Owls' earlier arrival and departure, coupled with superior body condition, were consistent among years and typical of a long-distance migration strategy. In contrast, the Northern Saw-whet Owls' later arrival, more lengthy passage, and variable body condition were more characteristic of a short-distance migrant strategy. Furthermore, Northern Saw-whet Owls' body condition was significantly lower during the irruptive year than during nonirruptive years, supporting the notion that population density affects their migratory condition. ?? 2006 The Raptor Research Foundation, Inc.

  13. Development of a Wireless and Passive SAW-Based Chemical Sensor for Organophosphorous Compound Detection.

    PubMed

    Xu, Fang-Qian; Wang, Wen; Xue, Xu-Feng; Hu, Hao-Liang; Liu, Xin-Lu; Pan, Yong

    2015-01-01

    A new wireless and passive surface acoustic wave (SAW)-based chemical sensor for organophosphorous compound (OC) detection is presented. A 434 MHz reflective delay line configuration composed by single phase unidirectional transducers (SPUDTs) and three shorted reflectors was fabricated on YZ LiNbO? piezoelectric substrate as the sensor element. A thin fluoroalcoholpolysiloxane (SXFA) film acted as the sensitive interface deposited onto the SAW propagation path between the second and last reflectors of the SAW device. The first reflector was used for the temperature compensation utilizing the difference method. The adsorption between the SXFA and OC molecules modulates the SAW propagation, especially for the time delay of the SAW, hence, the phase shifts of the reflection peaks from the corresponding reflectors can be used to characterize the target OC. Prior to the sensor fabrication, the coupling of modes (COM) and perturbation theory were utilized to predict the SAW device performance and the gas adsorption. Referring to a frequency-modulated continuous wave (FMCW)-based reader unit, the developed SAW chemical sensor was wirelessly characterized in gas exposure experiments for dimethylmethylphosphonate (DMMP) detection. Sensor performance parameters such as phase sensitivity, repeatability, linearity, and temperature compensation were evaluated experimentally. PMID:26633419

  14. Assessment of Present State-of-the-art Sawing Technology of Large Diameter Ingots for Solar Sheet Material

    NASA Technical Reports Server (NTRS)

    Yoo, H. I.

    1978-01-01

    Work is reported on: (1) slicing of the ingots with the multiblade slurry saw, the multiwire slurry saw and the I.D. saw, (2) characterization of the sliced wafers, and (3) analysis of add-on slicing cost based on Solar Array Manufacturing Industry Costing Standard.

  15. [Determination of the power jigsaw sawing velocity from the morphological properties of the affected human skin].

    PubMed

    Nazarov, Iu V; Tolmachev, I A

    2014-01-01

    The objective of the present work was to elucidate the characteristic morphological features of the injuries inflicted to the human skin by a power jigsaw depending on the sawing velocity. The study has demonstrated the possibility of mathematical analysis of the sawing velocity based on the morphological peculiarities of the injury to the skin. The data obtained indicate that forensic medical expertise of the injuries inflicted by a power jigsaw can be based on the study of the width of the abraded edges of the wound in order to determine the sawing velocity. PMID:25796928

  16. Noise source identification and control of a contractor grade table saw

    NASA Astrophysics Data System (ADS)

    Bleedorn, Kristin; McKee, Matthew; Yarbough, Dale; Yu, Chen; Zechmann, Edward L.; Mann, J. Adin

    2002-05-01

    Sponsored by the National Institute for Occupational Safety and Health (NIOSH) as part of their initiative to explore noise reduction strategies for construction equipment, a team of engineering students at Iowa State University studied a contractor grade table saw. Based on standards, published work, and preliminary tests, a repeatable noise measurement procedure was developed for the table saw operation. The wood-feed rate and force were measured. With the saw operating in a standard and consistent manner, noise sources on the saw were identified using sound intensity measurement techniques and through the application of noise control strategies to individual sources. At this stage, noise control strategies, such as enclosing the motor, are effective for noise source identification but not practical. The effectiveness of both approaches to identifying the noise sources will be discussed. Based on rank ordering the contribution of each noise source to the overall sound levels, permanent noise control strategies are suggested.

  17. Development of a hydrogen gas sensor using a double SAW resonator system at room temperature.

    PubMed

    Yunusa, Zainab; Hamidon, Mohd Nizar; Ismail, Alyani; Mohd Isa, Maryam; Yaacob, Mohd Hanif; Rahmanian, Saeed; Ibrahim, Siti Azlida; Shabaneh, Arafat A A

    2015-01-01

    A double SAW resonator system was developed as a novel method for gas sensing applications. The proposed system was investigated for hydrogen sensing. Commercial Surface Acoustic Wave (SAW) resonators with resonance frequencies of 433.92 MHz and 433.42 MHz were employed in the double SAW resonator system configuration. The advantages of using this configuration include its ability for remote measurements, and insensitivity to vibrations and other external disturbances. The sensitive layer is composed of functionalized multiwalled carbon nanotubes and polyaniline nanofibers which were deposited on pre-patterned platinum metal electrodes fabricated on a piezoelectric substrate. This was mounted into the DSAWR circuit and connected in parallel. The sensor response was measured as the difference between the resonance frequencies of the SAW resonators, which is a measure of the gas concentration. The sensor showed good response towards hydrogen with a minimum detection limit of 1%. PMID:25730480

  18. Method for nondestructive testing of the film coating behavior of surface acoustic wave (SAW) sensors

    NASA Astrophysics Data System (ADS)

    Taslakov, M. A.; Avramov, I. D.

    2010-04-01

    This paper presents a practical non-destructive method for studying the film coating behavior of SAW devices by using a water soluble dielectric film (manitol) deposited on the SAW device surface by resistive evaporation. After measuring the electrical parameters of the film coated SAW device, the film can easily be removed from its surface by water rinsing without causing any damage to it. The SAW device can then be used over and over again in a large number of film depositions. The method was tested on a 1 GHz surface transverse wave (STW) resonator coated with manitol of varying thickness. After each coating and evaluation, the STW device was successfully recovered without significant performance degradation. Data is presented on the electrical changes of the STW device as a result of depositing manitol coatings of various thicknesses.

  19. Feasibility of ultra-wideband SAW RFID tags meeting FCC rules.

    PubMed

    Härmä, Sanna; Plessky, Victor P; Li, Xianyi; Hartogh, Paul

    2009-04-01

    We discuss the feasibility of surface acoustic wave (SAW) radio-frequency identification (RFID) tags that rely on ultra-wideband (UWB) technology. We propose a design of a UWB SAW tag, carry out numerical experiments on the device performance, and study signal processing in the system. We also present experimental results for the proposed device and estimate the potentially achievable reading distance. UWB SAW tags will have an extremely small chip size (<0.5 x 1 mm(2)) and a low cost. They also can provide a large number of different codes. The estimated read range for UWB SAW tags is about 2 m with a reader radiating as low as <0.1 mW power levels with an extremely low duty factor. PMID:19406710

  20. Study of a high-precision SAW-MOEMS strain sensor with laser optics

    NASA Astrophysics Data System (ADS)

    Liu, Xinwei; Chen, Shufen; Li, Honglang; Zou, Zhengfeng; Fu, Lei; Meng, Yanbin

    2015-02-01

    A novel structure design of a surface acoustic wave (SAW) micro-optic-electro-mechanical-system (MOEMS) strain sensor with a light readout unit is presented in this paper. By measuring the polarization intensity ratio of the TE/TM mode outputted from the waveguide, the strain produced from an object can be measured precisely. The basic working principle of the SAW MOEMS strain sensor is introduced and the mathematical model of the strain sensor system is established. The SAW characteristics effected by the strain sensor are mathematically deduced. The coupling coefficient between the SAW modes and light modes can be calculated based on the theory of coupling modes. The conversion coefficient of polarized light modes is obtained. Due to the restrictions of the specific parameters of the device, the level of technology and the material characteristics, the sensitivity of the strain sensor system is calculated through simulation as 0.1???, with a dynamic range of 0 ~ ±50???.

  1. Modeling electrical response of polymer-coated SAW resonators by equivalent circuit representation.

    PubMed

    Kshetrimayum, Roshan; Yadava, R D S; Tandon, R P

    2011-07-01

    The paper presents an equivalent circuit model of the polymer coated surface acoustic wave (SAW) resonators by combining coupling-of-mode (COM) description of SAW resonators and perturbation calculation of SAW propagation under polymer loading. An expression for the motional load produced by polymer coating is deduced in terms of COM parameters and polymer characteristics. In addition, expressions for the shifts in resonance frequency and attenuation due to polymer loading are obtained. Simulation results are presented for one-port and two-port resonator devices coated with viscoelastic thin polymer film. The influence of polymer film on resonator response is studied with regard to variations in film thickness and shear modulus. The model simplifies understanding of polymer-coated SAW sensors. PMID:21236460

  2. Resonant frequency characteristics of a SAW device attached to resonating micropillars.

    PubMed

    Ramakrishnan, N; Nemade, Harshal B; Palathinkal, Roy Paily

    2012-01-01

    Recently we reported experimental and simulation results on an increase in resonance frequency of a SAW resonator caused by mass loading of micropillars made of SU-8, attached normal to the surface of the resonator. We concluded that SAW resonator and the SU-8 micropillars in unison form a system of coupled resonators. We have now extended this work and performed a finite element method simulation to study the resonance frequency characteristics of the SAW-based coupled resonator. In this paper we report the effect of the resonance frequency of the micropillars on the resonance frequency of the system of coupled resonators, and observe the coupling of micropillar resonance and the propagating SAW as described in the well known Dybwad system of coupled resonators. PMID:22666001

  3. Voltage controlled SAW velocity in GaAs/LiNbO(3)-hybrids.

    PubMed

    Rotter, M; Ruile, W; Wixforth, A; Kotthaus, J P

    1999-01-01

    The combination of the electronic properties of semiconductor heterojunctions and the acoustic properties of piezoelectric materials yields very promising surface acoustic wave (SAW) hybrid systems. Quasi-monolithical integration of thin GaAs/InGaAs/AlGaAs-quantum well structures on LiNbO(3) SAW devices is achieved using the epitaxial lift-off (ELO) technique. The conductivity of the two-dimensional electron system in the quantum well, which can be controlled via field effect, modifies the velocity of the SAW. Due to the high electromechanical coupling coefficient of LiNbO(3) a large phase shift can be obtained. As an example for this new class of voltage-tunable single chip SAW devices, a voltage-controlled oscillator (VCO) is presented in which the output frequency can be tuned by an applied gate voltage. PMID:18238405

  4. Development of a Hydrogen Gas Sensor Using a Double Saw Resonator System at Room Temperature

    PubMed Central

    Yunusa, Zainab; Hamidon, Mohd Nizar; Ismail, Alyani; Isa, Maryam Mohd; Yaacob, Mohd Hanif; Rahmanian, Saeed; Ibrahim, Siti Azlida; Shabaneh, Arafat A.A

    2015-01-01

    A double SAW resonator system was developed as a novel method for gas sensing applications. The proposed system was investigated for hydrogen sensing. Commercial Surface Acoustic Wave (SAW) resonators with resonance frequencies of 433.92 MHz and 433.42 MHz were employed in the double SAW resonator system configuration. The advantages of using this configuration include its ability for remote measurements, and insensitivity to vibrations and other external disturbances. The sensitive layer is composed of functionalized multiwalled carbon nanotubes and polyaniline nanofibers which were deposited on pre-patterned platinum metal electrodes fabricated on a piezoelectric substrate. This was mounted into the DSAWR circuit and connected in parallel. The sensor response was measured as the difference between the resonance frequencies of the SAW resonators, which is a measure of the gas concentration. The sensor showed good response towards hydrogen with a minimum detection limit of 1%. PMID:25730480

  5. PEPPER (BELL) : Capsicum annuum (L.) 'Enterprise' Southern armyworm (SAW); Spodoptera eridania (Stoll)

    E-print Network

    Ma, Lena

    (E62) PEPPER (BELL) : Capsicum annuum (L.) 'Enterprise' Southern armyworm (SAW); Spodoptera ARMYWORM IN BELL PEPPER, 1997: The number of biorational products including Bacillus thuringiensis of such selective materials against two Spodoptera species attacking bell pepper in south Florida. Greenhouse

  6. Early development of rostrum saw-teeth in a fossil ray tests classical theories of the evolution of vertebrate dentitions.

    PubMed

    Smith, Moya Meredith; Riley, Alex; Fraser, Gareth J; Underwood, Charlie; Welten, Monique; Kriwet, Jürgen; Pfaff, Cathrin; Johanson, Zerina

    2015-10-01

    In classical theory, teeth of vertebrate dentitions evolved from co-option of external skin denticles into the oral cavity. This hypothesis predicts that ordered tooth arrangement and regulated replacement in the oral dentition were also derived from skin denticles. The fossil batoid ray Schizorhiza stromeri (Chondrichthyes; Cretaceous) provides a test of this theory. Schizorhiza preserves an extended cartilaginous rostrum with closely spaced, alternating saw-teeth, different from sawfish and sawsharks today. Multiple replacement teeth reveal unique new data from micro-CT scanning, showing how the 'cone-in-cone' series of ordered saw-teeth sets arrange themselves developmentally, to become enclosed by the roots of pre-existing saw-teeth. At the rostrum tip, newly developing saw-teeth are present, as mineralized crown tips within a vascular, cartilaginous furrow; these reorient via two 90° rotations then relocate laterally between previously formed roots. Saw-tooth replacement slows mid-rostrum where fewer saw-teeth are regenerated. These exceptional developmental data reveal regulated order for serial self-renewal, maintaining the saw edge with ever-increasing saw-tooth size. This mimics tooth replacement in chondrichthyans, but differs in the crown reorientation and their enclosure directly between roots of predecessor saw-teeth. Schizorhiza saw-tooth development is decoupled from the jaw teeth and their replacement, dependent on a dental lamina. This highly specialized rostral saw, derived from diversification of skin denticles, is distinct from the dentition and demonstrates the potential developmental plasticity of skin denticles. PMID:26423843

  7. Early development of rostrum saw-teeth in a fossil ray tests classical theories of the evolution of vertebrate dentitions

    PubMed Central

    Smith, Moya Meredith; Riley, Alex; Fraser, Gareth J.; Underwood, Charlie; Welten, Monique; Kriwet, Jürgen; Pfaff, Cathrin; Johanson, Zerina

    2015-01-01

    In classical theory, teeth of vertebrate dentitions evolved from co-option of external skin denticles into the oral cavity. This hypothesis predicts that ordered tooth arrangement and regulated replacement in the oral dentition were also derived from skin denticles. The fossil batoid ray Schizorhiza stromeri (Chondrichthyes; Cretaceous) provides a test of this theory. Schizorhiza preserves an extended cartilaginous rostrum with closely spaced, alternating saw-teeth, different from sawfish and sawsharks today. Multiple replacement teeth reveal unique new data from micro-CT scanning, showing how the ‘cone-in-cone’ series of ordered saw-teeth sets arrange themselves developmentally, to become enclosed by the roots of pre-existing saw-teeth. At the rostrum tip, newly developing saw-teeth are present, as mineralized crown tips within a vascular, cartilaginous furrow; these reorient via two 90° rotations then relocate laterally between previously formed roots. Saw-tooth replacement slows mid-rostrum where fewer saw-teeth are regenerated. These exceptional developmental data reveal regulated order for serial self-renewal, maintaining the saw edge with ever-increasing saw-tooth size. This mimics tooth replacement in chondrichthyans, but differs in the crown reorientation and their enclosure directly between roots of predecessor saw-teeth. Schizorhiza saw-tooth development is decoupled from the jaw teeth and their replacement, dependent on a dental lamina. This highly specialized rostral saw, derived from diversification of skin denticles, is distinct from the dentition and demonstrates the potential developmental plasticity of skin denticles. PMID:26423843

  8. [Forensic medical characteristic of sawed injuries inflicted to the long tubular bones by a power jigsaw].

    PubMed

    Nazarov, Iu V; Tolmachev, I A

    2013-01-01

    The main aspects of investigations devoted to forensic medical characteristic of sawed injuries inflicted to the long tubular bones by a power jigsaw are considered. The mathematical model has been developed making it possible to determine the frequency of backward and forward movements of the jigsaw blade from the morphological features of the injuries to long tubular bones of man and to estimate the sawing rate for the further identification of the instrument of crime. PMID:23789407

  9. Optimal selection of piezoelectric substrates and crystal cuts for SAW-based pressure and temperature sensors.

    PubMed

    Zhang, Xiangwen; Wang, Fei-Yue; Li, Li

    2007-06-01

    In this paper, the perturbation method is used to study the velocity shift of surface acoustic waves (SAW) caused by surface pressure and temperature variations of piezoelectric substrates. Effects of pressures and temperatures on elastic, piezoelectric, and dielectric constants of piezoelectric substrates are fully considered as well as the initial stresses and boundary conditions. First, frequency pressure/temperature coefficients are introduced to reflect the relationship between the SAW resonant frequency and the pressure/temperature of the piezoelectric substrates. Second, delay pressure/temperature coefficients are introduced to reflect the relationship among the SAW delay time/phase and SAW delay line-based sensors' pressure and temperature. An objective function for performance evaluation of piezoelectric substrates is then defined in terms of their effective SAW coupling coefficients, power flow angles (PFA), acoustic propagation losses, and pressure and temperature coefficients. Finally, optimal selections of piezo-electric substrates and crystal cuts for SAW-based pressure, temperature, and pressure/temperature sensors are derived by calculating the corresponding objective function values among the range of X-cut, Y-cut, Z-cut, and rotated Y-cut quartz, lithium niobate, and lithium tantalate crystals in different propagation directions. PMID:17571819

  10. Ultra-wideband communication system prototype using orthogonal frequency coded SAW correlators.

    PubMed

    Gallagher, Daniel R; Kozlovski, Nikolai Y; Malocha, Donald C

    2013-03-01

    This paper presents preliminary ultra-wideband (UWB) communication system results utilizing orthogonal frequency coded SAW correlators. Orthogonal frequency coding (OFC) and pseudo-noise (PN) coding provides a means for spread-spectrum UWB. The use of OFC spectrally spreads a PN sequence beyond that of CDMA; allowing for improved correlation gain. The transceiver approach is still very similar to that of the CDMA approach, but provides greater code diversity. Use of SAW correlators eliminates many of the costly components that are typically needed in the intermediate frequency (IF) section in the transmitter and receiver, and greatly reduces the signal processing requirements. Development and results of an experimental prototype system with center frequency of 250 MHz are presented. The prototype system is configured using modular RF components and benchtop pulse generator and frequency source. The SAW correlation filters used in the test setup were designed using 7 chip frequencies within the transducer. The fractional bandwidth of approximately 29% was implemented to exceed the defined UWB specification. Discussion of the filter design and results are presented and are compared with packaged device measurements. A prototype UWB system using OFC SAW correlators is demonstrated in wired and wireless configurations. OFC-coded SAW filters are used for generation of a transmitted spread-spectrum UWB and matched filter correlated reception. Autocorrelation and cross-correlation system outputs are compared. The results demonstrate the feasibility of UWB SAW correlators for use in UWB communication transceivers. PMID:23475929

  11. An interrogation unit for passive wireless SAW sensors based on fourier transform.

    PubMed

    Hamsch, Matthias; Hoffmann, Rene; Buff, Werner; Binhack, Michael; Klett, Stefan

    2004-11-01

    The application of surface acoustic wave (SAW) resonators as sensor elements for different physical parameters such as temperature, pressure, and force has been well-known for several years. The energy storage in the SAW and the direct conversion from physical parameter to a parameter of the wave, such as frequency or phase, enables the construction of a passive sensor that can be interrogated wireless. This paper presents a temperature-measurement system based on passive wireless SAW sensors. The principle of SAW sensors and SAW sensor interrogation is discussed briefly. A new measurement device developed for analyzing the sensor signals is introduced. Compared to former interrogation units that detect resonance frequency of the SAW resonator by comparing amplitudes of sensor response signals related to different stimulating frequencies, the new equipment is able to measure the resonance frequency directly by calculating a Fourier transformation of the resonator response signal. Measurement results of an experimental setup and field tests are presented and discussed. PMID:15600089

  12. Mass sensitivity calculation of the protein layer using love wave SAW biosensor.

    PubMed

    Lee, Sangdae; Kim, Ki Bok; Il Kim, Yong

    2012-07-01

    Love waves, a variety of surface acoustic waves (SAWs), can be used to detect very small biological surface interactions and so have a wide range of potential applications. To demonstrate the practicality of a Love wave SAW biosensor, we fabricated a 155-MHz Love wave SAW biosensor and compared it with a commercial surface Plasmon resonance (SPR) using glycerol-water solution with known densities and viscosities to calibrate the response signals of the biosensors. And the mass per unit area of anti-mouse IgG bound with protein G onto the sensitive layer of the biosensor was calculated on the basis of the calibration result. The sensitivity of the Love wave SAW biosensor was the same as or greater than that of the SPR biosensor. Furthermore, the Love wave SAW biosensor was capable of measuring a much wider range of viscosities than the SPR biosensor. Although the operating principle of the Love wave SAW biosensor is completely different from that of the SPR biosensor, the subtle changes in the viscoelastic properties of the biological layer that accompany biological binding reactions on the sensitive layer can be monitored and measured in the same ways as with the SPR biosensor. PMID:22966717

  13. Considerations for Dynamic Temperature Compensation of Wideband Ladder-type SAW Filter

    NASA Astrophysics Data System (ADS)

    Nakamura, Nobuyuki; Komatsu, Tomoya; Omori, Tatsuya; Hashimoto, Ken-Ya; Yamaguchi, Masatsune

    Because of there excellent features such as small-size, wide bandwidth, and low insertion loss, the ladder-type filters based on surface acoustic wave (SAW) technology have been widely used as radio-frequency (RF) filters in mobile communications. We can make wide bandwidth, and low insertion loss, the ladder-type SAW filters on a Cu-grating/15°LiNbO3 substrate structure. On the other hand, it is said that wide bandwidth filters is bad temperature characteristic. So this paper discusses dynamic temperature compensation of wideband ladder-type SAW filters. First, we investigate how wide tunability is achievable using variable capacitors parallel- and/or series-connectted to SAW resonators in the filter configuration. Second, we measured the temperature characteristic of resonator. Finally, we simulated temperature compensation of wideband ladder-type SAW filters. As a result, we were able to compensate the change of the characteristic with the ladder-type SAW filter connected variable capacitors.

  14. Evolutionary origins and development of saw-teeth on the sawfish and sawshark rostrum (Elasmobranchii; Chondrichthyes)

    PubMed Central

    Welten, Monique; Smith, Moya Meredith; Underwood, Charlie; Johanson, Zerina

    2015-01-01

    A well-known characteristic of chondrichthyans (e.g. sharks, rays) is their covering of external skin denticles (placoid scales), but less well understood is the wide morphological diversity that these skin denticles can show. Some of the more unusual of these are the tooth-like structures associated with the elongate cartilaginous rostrum ‘saw’ in three chondrichthyan groups: Pristiophoridae (sawsharks; Selachii), Pristidae (sawfish; Batoidea) and the fossil Sclerorhynchoidea (Batoidea). Comparative topographic and developmental studies of the ‘saw-teeth’ were undertaken in adults and embryos of these groups, by means of three-dimensional-rendered volumes from X-ray computed tomography. This provided data on development and relative arrangement in embryos, with regenerative replacement in adults. Saw-teeth are morphologically similar on the rostra of the Pristiophoridae and the Sclerorhynchoidea, with the same replacement modes, despite the lack of a close phylogenetic relationship. In both, tooth-like structures develop under the skin of the embryos, aligned with the rostrum surface, before rotating into lateral position and then attaching through a pedicel to the rostrum cartilage. As well, saw-teeth are replaced and added to as space becomes available. By contrast, saw-teeth in Pristidae insert into sockets in the rostrum cartilage, growing continuously and are not replaced. Despite superficial similarity to oral tooth developmental organization, saw-tooth spatial initiation arrangement is associated with rostrum growth. Replacement is space-dependent and more comparable to that of dermal skin denticles. We suggest these saw-teeth represent modified dermal denticles and lack the ‘many-for-one’ replacement characteristic of elasmobranch oral dentitions. PMID:26473044

  15. Evolutionary origins and development of saw-teeth on the sawfish and sawshark rostrum (Elasmobranchii; Chondrichthyes).

    PubMed

    Welten, Monique; Smith, Moya Meredith; Underwood, Charlie; Johanson, Zerina

    2015-09-01

    A well-known characteristic of chondrichthyans (e.g. sharks, rays) is their covering of external skin denticles (placoid scales), but less well understood is the wide morphological diversity that these skin denticles can show. Some of the more unusual of these are the tooth-like structures associated with the elongate cartilaginous rostrum 'saw' in three chondrichthyan groups: Pristiophoridae (sawsharks; Selachii), Pristidae (sawfish; Batoidea) and the fossil Sclerorhynchoidea (Batoidea). Comparative topographic and developmental studies of the 'saw-teeth' were undertaken in adults and embryos of these groups, by means of three-dimensional-rendered volumes from X-ray computed tomography. This provided data on development and relative arrangement in embryos, with regenerative replacement in adults. Saw-teeth are morphologically similar on the rostra of the Pristiophoridae and the Sclerorhynchoidea, with the same replacement modes, despite the lack of a close phylogenetic relationship. In both, tooth-like structures develop under the skin of the embryos, aligned with the rostrum surface, before rotating into lateral position and then attaching through a pedicel to the rostrum cartilage. As well, saw-teeth are replaced and added to as space becomes available. By contrast, saw-teeth in Pristidae insert into sockets in the rostrum cartilage, growing continuously and are not replaced. Despite superficial similarity to oral tooth developmental organization, saw-tooth spatial initiation arrangement is associated with rostrum growth. Replacement is space-dependent and more comparable to that of dermal skin denticles. We suggest these saw-teeth represent modified dermal denticles and lack the 'many-for-one' replacement characteristic of elasmobranch oral dentitions. PMID:26473044

  16. Metabolomics study of Saw palmetto extracts based on 1H NMR spectroscopy.

    PubMed

    de Combarieu, Eric; Martinelli, Ernesto Marco; Pace, Roberto; Sardone, Nicola

    2015-04-01

    Preparations containing Saw palmetto extracts are used in traditional medicine to treat benign prostatic hyperplasia. According to the European and the American Pharmacopoeias, the extract is obtained from comminuted Saw palmetto berries by a suitable extracting procedure using ethanol or supercritical carbon dioxide or a mixture of n-hexane and methylpentanes. In the present study an approach to metabolomics profiling using nuclear magnetic resonance (NMR) has been used as a finger-printing tool to assess the overall composition of the extracts. The phytochemical analysis coupled with principal component analysis (PCA) showed the same composition of the Saw palmetto extracts obtained with carbon dioxide and hexane with minor not significant differences for extracts obtained with ethanol. In fact these differences are anyhow lower than the batch-to-batch variability ascribable to the natural-occurring variability in the Saw palmetto fruits' phytochemical composition. The fingerprinting analysis combined with chemometric method, is a technique, which would provide a tool to comprehensively assess the quality control of Saw palmetto extracts. PMID:25707588

  17. SAW characteristics of AlN films sputtered on silicon substrates.

    PubMed

    Clement, M; Vergara, L; Sangrador, J; Iborra, E; Sanz-Hervás, A

    2004-04-01

    This article is focused on the analysis of the electroacoustic response of surface acoustic wave (SAW) filters made of aluminium nitride (AlN) thin films on various types of Si wafers. AlN films with (00.2) orientation were deposited by RF reactive sputtering of an Al target in Ar and N(2) admixtures on Si(100) and (111) wafers with resistivities ranging between 10 and 2000 Omega cm. The electroacoustic response of SAW filters with an acoustic wavelength of 40 microm was analysed by measuring the Sij parameters with a network analyser. We have determined that the out-of-band loss is directly related to the Si substrate resistivity, varying from 26 dB for 10 Omega cm to 55 dB for 2000 Omega cm. The SAW velocity depends on the orientation of the Si wafer, being approximately 4700 m/s for Si(111) and 5100 m/s for Si(100). The electroacoustic responses of the SAW filters were fitted by computations based on a simple circuital model that takes into account parasitic effects such as airborne electromagnetic coupling and conduction through the substrate. This procedure provides accurate values of the electromechanical coupling factor k2 even for devices with poor characteristics. Good quality SAW filters of AlN on high resistivity Si(100) wafers with k2 larger than 0.12% are demonstrated. PMID:15047319

  18. Effect of multiblade slurry saw induced damage on silicon solar cells

    NASA Technical Reports Server (NTRS)

    Daud, T.; Liu, J. K.; Pollock, G. A.; Koliwad, K. M.

    1978-01-01

    A correlation between the optimum etch loss and the depth of damage is established using wafers produced by the Multiblade Slurry (MBS) and the Internal Diameter (ID) saws. The observations are based on the measurement of the performance of solar cells fabricated on these wafers. Sample preparation and test results are described and the following conclusions are made: (1) the amount of silicon removal necessary for optimum solar cell performance coincides with the depth of saw-induced damage; (2) optimization of cell performance is not affected by the method of silicon removal; (3) sawing conditions should be optimized to minimize the extent of saw-induced damage; (4) the MBS saw is found to induce damage to a lesser extent; (5) since the extent of damage in MBS-sawn wafers is in the limit of etch loss required in texture etching, it is possible to achieve optimum improvement in cell performance by merely texture etching the surface of as-sawn wafers.

  19. Comparison of saw ginning and high-speed roller ginning with different lint cleaners of mid-south grown cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four cotton cultivars were ginned with a saw-gin equipment line and also with a high-speed roller-gin line. The saw-gin line using an air-jet and controlled-batt saw-type lint cleaner was compared to the high-speed roller-gin line using two versions of an experimental lint cleaner, of a basic design...

  20. Assessment of present state-of-the-art sawing technology of large diameter ingots for solar sheet material

    NASA Technical Reports Server (NTRS)

    Yoo, H. I.

    1977-01-01

    The objective of this program is to assess the present state-of-the-art sawing technology of large diameter silicon ingots (3 inch and 4 inch diameter) for solar sheet materials. During this period, work has progressed in three areas: (1) slicing of the ingots with the multiblade slurry saw and the I.D. saw, (2) characterization of the sliced wafers, and (3) analysis of direct labor, expendable material costs, and wafer productivity.

  1. Enhanced spectral efficiency using bandwidth switchable SAW filtering for mobile satellite communications systems

    NASA Technical Reports Server (NTRS)

    Peach, Robert; Malarky, Alastair

    1990-01-01

    Currently proposed mobile satellite communications systems require a high degree of flexibility in assignment of spectral capacity to different geographic locations. Conventionally this results in poor spectral efficiency which may be overcome by the use of bandwidth switchable filtering. Surface acoustic wave (SAW) technology makes it possible to provide banks of filters whose responses may be contiguously combined to form variable bandwidth filters with constant amplitude and phase responses across the entire band. The high selectivity possible with SAW filters, combined with the variable bandwidth capability, makes it possible to achieve spectral efficiencies over the allocated bandwidths of greater than 90 percent, while retaining full system flexibility. Bandwidth switchable SAW filtering (BSSF) achieves these gains with a negligible increase in hardware complexity.

  2. Relationship between acceleration and the scattering matrix in a SAW-MEMS accelerometer.

    PubMed

    Guerra-Pulido, Jaime Octavio; Pérez-Alcázar, Pablo Roberto

    2011-07-01

    Phase velocity of a surface acoustic wave (SAW) varies when the electric field associated with the wave interacts with a conductive material located above the propagation plane. In this paper, we propose a general method to approximate the scattering matrix when the conductive structure has a specific geometry. This structure has reflective properties of SAW. As an example, we considered a previously reported SAW-MEMS microaccelerometer which mainly consists of a slotted beam. By applying this method, we obtained the relationship between acceleration and the reflection and transmission coefficients. The dynamic of the slotted beam was studied using the finite element method (FEM). It was observed that relatively small variations in the size of the microstructure could cause significant changes in the reflection and transmission coefficients. We also show that the slotted beam acts as an acoustic wave bandpass filter, and its response is similar to that of reflective gratings, but with linear phase. PMID:21768030

  3. Objective classification of performance in the use of a piercing saw in jewellery making.

    PubMed

    Baber, Chris; Cengiz, Tulin Gunduz; Starke, Sandra; Parekh, Manish

    2015-11-01

    Data from 15 jewellery students, in their 1st and 3rd years of training, were analysed to show how data collected from work settings can be used to objectively evaluate performance in the use of tools. Participants were asked to use a piercing saw to cut 5 lines in a piece of metal. Performance was categorised in terms of functional dynamics. Data from strain gauges and a tri-axial accelerometer (built into the handle of the saw) were recorded and thirteen metrics derived from these data. The key question for this paper is which metrics could be used to distinguish levels of ability. Principal Components Analysis identified five components: sawing action; grasp of handle; task completion time; lateral deviation of strokes; and quality of lines cut. Using representative metrics for these components, participants could be ranked in terms of performance (low, medium, high) and statistical analysis showed significant differences between participants on key metrics. PMID:26154220

  4. Modelling of contact regimes in wire sawing with dissipative particle dynamics.

    PubMed

    Bierwisch, C; Kübler, R; Kleer, G; Moseler, M

    2011-06-28

    Optimization of the wire sawing process of silicon ingots requires a profound understanding of the dynamic interaction of wire, slurry and silicon material. In this paper, the influence of wire velocity and applied wire stress on the process is investigated using dissipative particle dynamics and discrete element simulations for modelling the fluid and the grains in the abrasive suspension. In our simulations, different contact regimes occur depending on grain shape and a stress balance within the system. We observed semi-contact for high wire stress and low wire velocity and non-contact for low stress and high velocities in agreement with predictions from elasto-hydrodynamic modelling. Our simulations suggest the usage of sharp grains, since in this case, stress localization on the base of the sawing groove occurs even in the non-contact regime. These insights are likely to provide a scientific base for the optimization of sawing rates and reduction of kerf loss. PMID:21576156

  5. Maintenance of stellite and tungsten carbide saw tips: respiratory health and exposure-response evaluations.

    PubMed Central

    Kennedy, S M; Chan-Yeung, M; Marion, S; Lea, J; Teschke, K

    1995-01-01

    OBJECTIVE--To study exposure to cobalt and chromium in saw maintenance rooms and test respiratory health among saw filers at lumber mills. Hard-metal lung disease is associated with cobalt in the manufacture of tungsten carbide tools; recently it has also been reported among tool maintenance workers. Lumber mills often use saws tipped with tungsten carbide or with a newer alloy, stellite (containing more cobalt, as well as chromium). METHODS--A cross sectional study of 118 saw filers at eight lumber mills was carried out that included a standardised questionnaire, spirometry, personal air sampling, and examination of tasks every 10 minutes (by observation). Comparison data were from a study of bus mechanics tested with similar methods. RESULTS AND CONCLUSION--Cobalt exposure was associated with tungsten carbide grinding but not with stellite grinding. Chromium exposure was associated mainly with stellite welding. Saw filers had a twofold increase in phlegm and wheeze (P < 0.01) and a threefold increase in cough, phlegm, and wheeze related to work (P < 0.001), but no increase in breathlessness. Stellite welding was associated with a significant increase in nasal symptoms and cough related to work and a small decrease in airflow (forced expiratory volume in one second/forced vital capacity (FEV1/FVC%), P < 0.05). Saw filers wet grinding with tungsten carbide had significant reductions in forced expiratory lung volumes (FEV1 and FVC, P < 0.05) and were significantly more likely to have FEV1 and FVC values in the abnormal range. Cobalt exposure (in wet grinding) and duration of work that involved tungsten carbide grinding were both associated with significant reductions in FEV1 and FVC. Average cobalt exposures in this study were about 5 micrograms/m3, well below the currently accepted permissible concentration, which suggests that the current workplace limit for cobalt may be too high. PMID:7735392

  6. Modeling and performance analysis of SAW reader systems for delay-line sensors.

    PubMed

    Scheiblhofer, Stefan; Schuster, Stefan; Stelzer, Andreas

    2009-10-01

    In this contribution, we present a comprehensive modeling approach for delay line-based surface acoustic wave (SAW) sensor reader systems, which provides valuable insight into the interaction of the individual system parameters. A parametric analysis of signal strength, noise, and quantization effects and consideration of important signal processing parameters, such as data windows and averaging, allows prediction of the achievable statistical measurement accuracy by closed-form solutions. The performance and capabilities of the derived model are verified on system design examples as well as multiple practical measurement scenarios, using a prototype 2.45-GHz frequency-stepped continuous-wave SAW reader system. PMID:19942515

  7. Optimization of frequency characteristics for SAW device using apodization weighting method

    NASA Astrophysics Data System (ADS)

    Zhou, Lei; Zhang, Kai-liang; Wang, Fang; Han, Ye-mei; Miao, Yin-ping; Li, Dong-mei; Liang, Sheng-fa

    2015-03-01

    In this paper, the positive influence of apodization weighting method on frequency characteristics of surface acoustic wave (SAW) temperature sensor is investigated. Simulation and experiment results show that side lobe suppression abilities of the sensor can be improved by using apodization weighting which is based on Chebyshev window. Meanwhile, we find that the side lobe of the sensor can be further restrained, when the dummy electrodes are removed. Frequency-temperature characteristics of the devices are independent of the inclusion of dummy electrodes. The apodization weighted SAW temperature sensor shows great application potential in occasions with strong electromagnetic interference.

  8. Clustering-based pattern recognition applied to chemical recognition using SAW array signals

    SciTech Connect

    Osbourn, G.C.; Bartholomew, J.W.; Frye, G.C.; Ricco, A.J.

    1994-05-01

    We present a new patter recognition (PR) technique for chemical identification using arrays of microsensors. The technique relies on a new empirical approach to k-dimensional cluster analysis which incorporates measured human visual perceptions of difficult 2- dimensional clusters. The method can handle nonlinear SAW array data, detects both unexpected (outlier) and unreliable array responses, and has no user-adjustable parameters. We use this technique to guide the development of arrays of thin-film-coated SAW (Surface Acoustic Wave) devices that produce optimal PR performance for distinguishing a variety of volatile organic compounds, organophosphonates and water.

  9. Aberrations in saw-tooth refractive lenses in short focal length x-ray focusing

    NASA Astrophysics Data System (ADS)

    Antimonov, Mikhail A.; Khounsary, Ali M.; Shastri, Sarvjit D.

    2013-10-01

    Saw-tooth refractive lenses (SRL) provide a comparatively attractive option for X-ray focusing for various reasons, including their simple, continuous tunability in energy and focal length. Optimal focusing of a conventional SRL at short focal lengths is limited by the SRL's length in relation to the focal length. Three approaches to overcome this limitation are described. Analytical solutions verified with ray-tracing are presented. These are bending, variation of the saw-tooth tip angles, and variation of the period.

  10. 76 FR 75504 - Table Saw Blade Contact Injuries; Notice of Extension of Time for Comments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-02

    ... protect the user from accidental contact with the blade. In the Federal Register of July 9, 2003 (68 FR... rule requiring specified warnings and instructions to address table saw blade contact injuries (76 FR... Act (``CPSA''), 15 U.S.C. 2051-2084. In the Federal Register of October 11, 2011 (76 FR 62678),...

  11. 77 FR 8751 - Table Saw Blade Contact Injuries; Reopening of the Comment Period

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-15

    ... accidental contact with the blade. In the Federal Register of July 9, 2003 (68 FR 40912) and September 5... blade contact injuries in the Federal Register of October 11, 2011 (76 FR 62678). CPSC staff also... warnings and instructions to address table saw blade contact injuries (76 FR at 62683). The ANPR...

  12. Langasite SAW temperature and oxygen multi-sensor P. Zheng,1,2

    E-print Network

    Greve, David.W.

    a langasite SAW device suitable for sensing temperature and oxygen concentration, with applications with conductivity dependent on the oxygen defect concentration. In metal oxides with predominant electron conductionO is the concentration of oxygen atoms on an oxygen site, oV is the concentration of doubly-negative oxygen vacancies, e

  13. On the Modeling of Electrical Response of SAW Resonator-based Sensors Versus Temperature

    NASA Astrophysics Data System (ADS)

    Ballandras, S.; Laroche, T.; Courjon, E.; Daniau, W.; Baron, T.; Garcia, J.; Alzuaga, S.

    Surface acoustic wave (SAW) resonators built on Langasite (LGS) are capable to withstand temperature in excess of 900? C and demonstration of wireless interrogation of packaged sensors up to 700? C has been achieved for several tens of hours. These promising results emphasize the need for an accurate characterization of the raw material in order to design SAW resonators with a high level of confidence in the prediction, particularly concerning the temperature coefficient of frequency (TCF). Several data set have been published for LGS, offering prediction capabilities but also a significant level of data dispersion. Therefore, the evaluation of the effective thermal properties of SAW under periodic gratings turns out less robust than expected. Based also on published data and on measurements achieved within the SAWHOT project, harmonic admittance calculations have been achieved for deriving the evolution of mixed matrix parameters allowing for accurate SAW device simulation at any temperature. Adjusting the temperature coefficients then yield improved sets of material coefficients for design purpose. Using these data, we have demonstrated the possibility to develop a differential temperature sensor operating at temperature up to 600°C.

  14. Single-atom manipulation mechanisms during a quantum corral construction Saw-Wai Hla*

    E-print Network

    Hla, Saw-Wai

    Single-atom manipulation mechanisms during a quantum corral construction Saw-Wai Hla* Nanoscale.2 Å. The experimental atom manipulation signals reveal remark- ably detailed atom movement behaviors on an atom-by-atom basis. Manipulation with a scanning tunneling microscope STM tip allows engineer- ing

  15. SAW COM-parameter extraction in AlN/diamond layered structures.

    PubMed

    Iriarte, Gonzalo F; Engelmark, Fredrik; Katardjiev, Ilia V; Plessky, Viktor; Yantchev, Ventsislav

    2003-11-01

    Highly c-axis oriented aluminum nitride (AlN) thin piezoelectric films have been grown on polycrystalline diamond substrates by pulsed direct current (DC) magnetron reactive sputter-deposition. The films were deposited at a substrate temperature below 50 degrees C (room temperature) and had a typical full width half maximum (FWHM) value of the rocking curve of the AlN-002-peak of 2.1 degrees. A variety of one-port surface acoustic wave (SAW) resonators have been designed and fabricated on top of the AlN films. The measurements indicate that various SAW modes are excited. The SAW phase velocities of up to 11.800 m/s have been measured. These results are in agreement with calculated dispersion curves of the AlN/diamond structure. Finally, the coupling of modes parameters have been extracted from S11 measurements using curve fitting for the first SAW mode, which indicate an effective coupling K2 of 0.91% and a Q factor of about 600 at a frequency of 1050 MHz. PMID:14682637

  16. SAW/GC detection of taggants and other volatile compounds associated with contraband materials

    NASA Astrophysics Data System (ADS)

    Staples, Edward J.; Watson, Gary W.; McGuirre, David S.; Williams, Dudley

    1997-02-01

    Research on a Surface Acoustic Wave (SAW) Gas Chromatography (GC) non-intrusive inspection system has demonstrated the ability to identify and quantify the presence of non- volatile contraband vapors in less than 10 seconds. The technique can be used to detect volatile compounds associated with the contraband compound as well. This is important because volatile taggants in explosives make them easy to detect and volatile organic compounds are routinely used in the manufacturing of illicit drugs. The results of tests with volatile organic compounds associated with drugs of abuse, and volatile taggants for explosives are presented. The latter materials are particularly useful in detecting plastic explosives and results for Semtex and C-4 spiked with a taggant show that detectability is improved. Similar testing protocols and methods for drugs, currency, organo-phosphate agents, and taggant compounds have also been demonstrated. The SAW/GC method needs no high voltages, utilizes essentially all solid state devices, and involves no radioactive or hazardous materials SAW detection systems have demonstrated dynamic ranges greater than 1,000,000 and the ability to selectively screen for vapors from explosive and drugs of abuse at the part per billion level with little or no interference. Most important for law-enforcement, SAW/GC devices can be produced in small packages at low cost.

  17. Recent results and trends in health monitoring with surface acoustic waves (SAW)

    NASA Astrophysics Data System (ADS)

    Tittmann, Bernhard R.

    2003-07-01

    This paper presents recent results based on the use of Surface Acoustic Waves (SAWs) for active sensors for health monitoring of a variety of structures. In the first example, SAWs were used in an acoustic waveguide effect in the fluid filled space between two surfaces. The effect was demonstrated for flat plates and for concentric cylinders. Pressure vessels with concentric cylinders are used in the power industry, where the position of an industrial lead screw is an improtant parameter. Wave travel over a length of up to 2 meters could be observed with little energy loss into the fluid. The second example, presents the use of Electromagnetic Acoustic Transducers (EMAT) for the rapid health monitoring of railroad wheels. In the third example, surface hugging wedges were used with conventional transducers to launch and detect SAWs for crack detection and mapping measurements on pressure vessel valve stems. The fourth example deals with health monitoring of living biomedical cells. In this case SAWs at hypersonic frequencies (1 GHz) were employed to image and monitor the health of the cells as the temperatures were raised. While these examples are still laboratory projects, some of them are finding their way into industrial applications.

  18. Development of fuzzy logic system to predict the SAW weldment shape profiles

    NASA Astrophysics Data System (ADS)

    Narang, H. K.; Mahapatra, M. M.; Jha, P. K.; Biswas, P.

    2012-09-01

    A fuzzy model was presented to predict the weldment shape profile of submerged arc welds (SAW) including the shape of heat affected zone (HAZ). The SAW bead-on-plates were welded by following a full factorial design matrix. The design matrix consisted of three levels of input welding process parameters. The welds were cross-sectioned and etched, and the zones were measured. A mapping technique was used to measure the various segments of the weld zones. These mapped zones were used to build a fuzzy logic model. The membership functions of the fuzzy model were chosen for the accurate prediction of the weld zone. The fuzzy model was further tested for a set of test case data. The weld zone predicted by the fuzzy logic model was compared with the experimentally obtained shape profiles and close agreement between the two was noted. The mapping technique developed for the weld zones and the fuzzy logic model can be used for on-line control of the SAW process. From the SAW fuzzy logic model an estimation of the fusion and HAZ can also be developed.

  19. SAW: System-Assisted Wear Leveling on the Write Endurance of NAND Flash Devices

    E-print Network

    Wong, Weng Fai

    - dates due to the physical characteristics of flash cells. It has to be erased first. Programming a pageSAW: System-Assisted Wear Leveling on the Write Endurance of NAND Flash Devices Chundong Wang@comp.nus.edu.sg} ABSTRACT The write endurance of NAND flash memory adversely im- pacts the lifetime of flash devices

  20. NON-RECIPROCAL SAW DEVICES FOR RF APPLICATIONS M. Rotter, W. Ruile

    E-print Network

    Ludwig-Maximilians-Universität, München

    employing the 'epitaxial lift-off' process described elsewhere [1,2]. A thin metal electrode on top. The epitaxial lift-off (ELO) technique was used for this purpose. Here, however, we would like to focus is propagating strongly influence the propagation parameters of the SAW itself. In the literature, the limiting

  1. Interpreting the effects of burning on pre-incineration saw marks in bone.

    PubMed

    Robbins, Samantha C; Fairgrieve, Scott I; Oost, Tracy S

    2015-01-01

    This study examined the effects of fire on the features associated with saw marks in bone. Both class and individual characteristics were examined using stereomicroscopy and scanning electron microscopy (SEM). Twenty-four semifleshed Sus scrofa L. tibiae were sawed into three sections with the middle section having deep and shallow false starts. Twelve saw blades of varying age and type were each used to cut two tibiae. In each case, the first tibia was burned in an outdoor open fire to the point of partial calcination. The second tibia, our control, was macerated using a heated enzyme solution. Controls and burned specimens were examined for the following characteristics: breakaway spur, tooth hop, false start, exit chipping, tooth imprint, breakaway notch, pull out striae, kerf flare, and blade drift. In general, there was parity in the observed characteristics in the burned samples using the SEM and the stereomicroscope. SEM observation, however, provided enhanced images, with the addition of observing individual tooth imprints, previously not visible. Therefore, this study recommends using an SEM for the examination of saw cuts in burnt bone. PMID:25088190

  2. The Income Volatility See-Saw: Implications for School Lunch. ERS Report Summary

    ERIC Educational Resources Information Center

    Newman, Constance

    2006-01-01

    Income volatility challenges the functioning of the safety net provided by U.S. Department of Agriculture (USDA) food assistance programs for low-income families in time of need. Low-income families may be on a see-saw of income changes that make it difficult for program administrators to accurately target benefits and to define sensible…

  3. Production Machine Shop Employment Competencies. Part Two: Saws, Drills, and Grinders.

    ERIC Educational Resources Information Center

    Bishart, Gus; Werner, Claire

    Competencies for production machine shop are provided for the second of four topic areas: saws, drills, and grinders. Each competency appears in a one-page format. It is presented as a goal statement followed by one or more "indicator" statements, which are performance objectives describing an ability that, upon attainment, will establish…

  4. Effects of Friction Reduction on Fiber Damage in a Saw-Type Lint Cleaner

    Technology Transfer Automated Retrieval System (TEKTRAN)

    U.S. cotton is at a competitive disadvantage from a fiber-quality standpoint, because lint cleaning is required for mechanically harvested cotton, and lint cleaning causes fiber damage. Lint-cleaning research has focused mainly on modifying saw-type lint cleaners, but the work reported here focuses...

  5. Observing the motion of seed coat fragments on a saw-type lint cleaner

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to observe how seed coat fragments (in ginned lint) reacted after colliding with grid bars mounted on a full-size saw-type lint cleaner. A high-speed video camera recorded the collision. A 45° and 105° grid bar were used in the study. The grid bars were labeled to describe t...

  6. Orientational anisotropy in oxygen dissociation on Rh,,110... Saw Wai Hla

    E-print Network

    Hla, Saw-Wai

    Orientational anisotropy in oxygen dissociation on Rh,,110... Saw Wai Hla ICTP, Strada Costiera 11 Scanning tunneling microscopy study of O2 dissociation on Rh 110 at 170 K shows a low-energy disso- ciation-9 Dissociative adsorption of O2 on Rh 110 occurs at tem- peratures above 100 K and leads to a variety of ordered

  7. Advances in SAW Gas Sensors Based on the Condensate-Adsorption Effect

    PubMed Central

    Liu, Jiuling; Wang, Wen; Li, Shunzhou; Liu, Minghua; He, Shitang

    2011-01-01

    A surface-acoustic-wave (SAW) gas sensor with a low detection limit and fast response for volatile organic compounds (VOCs) based on the condensate-adsorption effect detection is developed. In this sensor a gas chromatography (GC) column acts as the separator element and a dual-resonator oscillator acts as the detector element. Regarding the surface effective permittivity method, the response mechanism analysis, which relates the condensate-adsorption effect, is performed, leading to the sensor performance prediction prior to fabrication. New designs of SAW resonators, which act as feedback of the oscillator, are devised in order to decrease the insertion loss and to achieve single-mode control, resulting in superior frequency stability of the oscillator. Based on the new phase modulation approach, excellent short-term frequency stability (±3 Hz/s) is achieved with the SAW oscillator by using the 500 MHz dual-port resonator as feedback element. In a sensor experiment investigating formaldehyde detection, the implemented SAW gas sensor exhibits an excellent threshold detection limit as low as 0.38 pg. PMID:22247697

  8. Granular dampers for the reduction of vibrations of an oscillatory saw

    NASA Astrophysics Data System (ADS)

    Heckel, Michael; Sack, Achim; Kollmer, Jonathan E.; Pöschel, Thorsten

    2012-10-01

    Instruments for surgical and dental application based on oscillatory mechanics submit unwanted vibrations to the operator's hand. Frequently the weight of the instrument's body is increased to dampen its vibration. Based on recent research regarding the optimization of granular damping we developed a prototype granular damper that attenuates the vibrations of an oscillatory saw twice as efficiently as a comparable solid mass.

  9. MTR, TRA603. INCANAL CONVEYOR TABLE, SAW TABLE, AND STORAGE AREA ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    MTR, TRA-603. IN-CANAL CONVEYOR TABLE, SAW TABLE, AND STORAGE AREA RACKS. DISCHARGE MECHANISM. BLAW-KNOX 3150-579-1, 12/1950. INL INDEX NO. 531-603-40-098-100302, REV. 3. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  10. Polygons Cuttable by a Circular Saw Erik D. Demaine \\Lambda Martin L. Demaine \\Lambda Craig S. Kaplan y

    E-print Network

    Demaine, Erik

    are slow and can be expensive even for straight cuts. For stained glass and ceramic tiles it is common the two saws is illustrated by looking at the blades. The key is that the blades have ``teeth'' to cut a path wider than the blade itself. A circular saw has teeth all around the circle, and hence the cut

  11. “Buzz-saw” noise: Prediction of the rotor-alone pressure field

    NASA Astrophysics Data System (ADS)

    McAlpine, A.; Schwaller, P. J. G.; Fisher, M. J.; Tester, B. J.

    2012-10-01

    Public expectations of lower environmental noise levels, and increasingly stringent legislative limits on aircraft noise, result in noise being a critical technical issue in the development of jet engines. Noise at take-off, when the engines are at high-power operating conditions, is a key reference level for engine noise certification. "Buzz-saw" noise is the dominant fan tone noise from modern high-bypass-ratio turbofan aircraft engines during take-off. Rotor-alone tones are the key component of buzz-saw noise. The rotor-alone pressure field is cut-off at subsonic fan tip speeds; buzz-saw noise is associated with supersonic fan tip speeds, or equivalently, high power engine operating conditions. A recent series of papers has described new work concerning the prediction of buzz-saw noise. The prediction method is based on modelling the nonlinear propagation of one-dimensional sawtooth waveforms. A sawtooth waveform is a simplified representation of the rotor-alone pressure field. Previous validation of the prediction method focussed entirely on reproducing the spectral characteristics of buzz-saw noise; this was dictated at that time by the availability of spectral data only for comparison between measurement and prediction. In this paper, full validation of the method by comparing measurement and prediction of the rotor-alone pressure field is published for the first time. It is shown that results from the modelling based on a one-dimensional sawtooth waveform capture the essential features of the rotor-alone pressure field as it propagates upstream inside a hard-walled inlet duct. This verifies that predictions of the buzz-saw noise spectrum, which are in good agreement with the measured data, are based on a model which reproduces the key physics of the noise generation process. Validation results for the rotor-alone pressure field in an acoustically lined inlet duct are also shown. Comparisons of the measured and predicted rotor-alone pressure field are more difficult to interpret because the acoustic lining significantly modifies the sawtooth waveform, but there remains good agreement with the measured spectral data. The buzz-saw noise prediction code used to generate the simulations in this paper has been used by the Rolls-Royce Noise Department since 2004.

  12. Room temperature fabrication of ZnO/ST-cut quartz SAW UV photodetector with small temperature coefficient.

    PubMed

    Tsai, Wen-Che; Kao, Hui-Ling; Liao, Kun-Hsu; Liu, Yu-Hao; Lin, Tzu-Ping; Jeng, Erik S

    2015-02-01

    Room-temperature fabricated ZnO/ST-cut quartz is adopted for SAW ultraviolet (UV) photodetector. The ST-cut quartz substrate and ZnO layer are used for SAW excitation and photodetection, respectively. High resolution x-ray diffraction (XRD) and photoluminescence (PL) measurement indicate that high quality ZnO films can be deposited on ST-cut quartz using radio frequency (RF) sputtering. As the SAW devices under UV illumination (6 mW/cm(2)), a downshift in frequency of about 35 KHz can be observed. The observed small temperature coefficient of frequency (TCF) indicates that SAW devices exhibit good temperature stability. The results present feasibility of using ZnO/ST-cut quartz SAW photodetectors in ultraviolet region. PMID:25836089

  13. Simulation and evaluation of a bone sawing procedure for orthognathic surgery based on an experimental force model.

    PubMed

    Yanping, Lin; Dedong, Yu; Xiaojun, Chen; Xudong, Wang; Guofang, Shen; Chengtao, Wang

    2014-03-01

    Bone sawing is widely used in orthognathic surgery to correct maxillary deformities. Successful execution of bone sawing requires a high level of dexterity and experience. A virtual reality (VR) surgical simulator can provide a safe, cost-effective, and repeatable training method. In this study, we developed a VR training simulator with haptic functions to simulate bone-sawing force, which was generated by the experimental force model. Ten human skulls were obtained in this study for the determination of surgical bone-sawing force. Using a 5-DOF machining center and a micro-reciprocating saw, bone specimens with different bone density were sawed at different feed rates (20, 40, and 60?mm/min) and spindle speeds (9800, 11,200 and 12,600 cycles per minute). The sawing forces were recorded with a piezoelectric dynamometer and a signal acquisition system. Linear correlation analysis of all experimental data indicates that there were significant positive linear correlations between bone-sawing force and bone density and tool feed rate and a moderate negative linear correlation with tool spindle rate. By performing multiple regression analysis, the prediction models for the bone-sawing procedure were determined. By employing Omega.6 as a haptic device, a medical simulator for the Lefort I osteotomy was developed based on an experimental force model. Comparison of the force-time curve acquired through experiments and the curve computed from the simulator indicate that the obtained forces based on the experimental force model and the acquired data had the same trend for the bone-sawing procedure of orthognathic surgery. PMID:24292329

  14. Wireless sensing using oscillator circuits locked to remote high-Q SAW resonators.

    PubMed

    Pohl, A; Ostermayer, G; Seifert, F

    1998-01-01

    This paper introduces a method of wireless read out of high Q surface acoustic wave (SAW) resonator sensors. The resonator is excited by a short RF pulse and decays after switching off the interrogating signal. In the measurement system, a gated phase locked loop (GPLL) locks to the resonance frequency of the SAW resonator within a few bursts. Then the frequency of the GPLL oscillator is synchronized to the resonance of the sensor and can be measured easily. The concept is intended to yield an alternative to interrogators with expensive signal processing. Considering the inherent limitations, the proposed system presents a low cost solution for temperature, force, torque, etc. measurements. We describe the sensors, the signals, and the implemented system. Results of temperature measurements using quartz resonators are presented, and merits and disadvantages are discussed. PMID:18244275

  15. Simulation research on cutting brittle optical material with diamond wire saw based on LS-DYNA

    NASA Astrophysics Data System (ADS)

    Wang, Jian; Liu, Jianbo; Xiao, Yonghao; Zhao, Shicao

    2014-08-01

    The quality of optical material cutting affects the efficiency and quality of follow-up polishing processing directly. Among various ways of cutting, the diamond wire saw cutting of fixed abrasive has advantages of narrow cutting seam, efficient cutting, high chip quality, little pollution to environment, ability to process bigger diameter workpiece, etc. So it has been used widely in optical material processing. In this paper, the coupled algorithm of FEM/SPH has been used to simulate deformation, fracture of brittle optical material in diamond grain cutting. The influence of workpiece feeding rate, cutting speed and cutting depth on the surface roughness are then analyzed in detail. Numerical simulation results show that the coupled algorithm efficiently explains the mechanism of material removal. From these results, we can not only determine optimum technology parameters for the manufacture of diamond wire saw, but also provide basis for improving the wire cutting efficiency and finished-product rate of optical material.

  16. Design and Fabrication of Passive Wireless SAW Sensor for Pressure Measurement

    NASA Astrophysics Data System (ADS)

    Hashimoto, Shuhei; Kuypers, Jan H.; Tanaka, Shuji; Esashi, Masayoshi

    This paper mainly presents the design and fabrication of a TDMA (time division multiple access) passive wireless pressure sensor using 2.45 GHz surface acoustic wave (SAW) delay lines. The SAW pressure sensor consists of two LiNbO3 substrates. The first layer is a pressure-detective thin substrate, on which an interdigital transducer (IDT) and reflectors are fabricated. The second layer is a support substrate, in which a reference pressure cavity is etched. These two substrates are directly bonded. The pressure measurement was successfully demonstrated in a pressure range of 20?280 kPa with good repeatability. In addition, the influence of a tire on the wireless interrogation of the sensor was investigated. Automobile tires have little negative influence on wireless communication, at least if they do not rotate.

  17. Chemical class specificity using self-assembled monolayers on SAW devices

    SciTech Connect

    Thomas, R.C.; Ricco, A.J.; Yang, H.C.; Dermody, D.; Crooks, R.M.

    1996-06-01

    We have studied the chemical selectivity and sensitivity of surface acoustic wave (SAW) sensors covered by (COO{sup {minus}}){sub 2}/Cu{sup 2+}-terminated interfaces by examining the response of self-assembled monolayer (SAM) films formed from the solution phase for 36, 84, and 180 h adsorption times. These organomercaptan SAMs were prepared on thin-film Au surfaces having variable, controlled grain size. The SAW response from the carboxylate coordinated Cu{sup 2+}-terminated SAM is compared to that from methyl-terminated SAM, as these films interact with a vapor-phase organophosphonate analyte and the vapors of common organic solvents. Results have implications for designing and reliably fabricating chemical sensors that respond to specific organic analytes.

  18. Higgs Decays in the Low Scale Type I See-Saw Model

    E-print Network

    C. Garcia Cely; A. Ibarra; E. Molinaro; S. T. Petcov

    2012-11-15

    The couplings of the low scale type I see-saw model are severely constrained by the requirement of reproducing the correct neutrino mass and mixing parameters, by the non-observation of lepton number and charged lepton flavour violating processes and by electroweak precision data. We show that all these constraints still allow for the possibility of an exotic Higgs decay channel into a light neutrino and a heavy neutrino with a sizable branching ratio. We also estimate the prospects to observe this decay at the LHC and discuss its complementarity to the indirect probes of the low scale type I see-saw model from experiments searching for the $\\mu\\to e\\gamma$ decay.

  19. New materials and multidimensional cluster analysis for SAW chemical sensor arrays

    SciTech Connect

    Ricco, A.J.; Osbourn, G.C.; Bartholomew, J.W.; Crooks, R.M.; Chuanjing, Xu; Allred, R.E.

    1994-05-01

    We use six-element arrays of 97-MHz ST-quartz surface acoustic wave (SAW) devices to detect changes in thin-film mass and mechanical properties resulting from sorption of analytes by films representing two new classes of chemical sensor interface: self-assembled monolayers (SAMs) and plasma-grafted films (PGFs). While these materials do not display exceptional chemical selectivity, various combinations of the 7 different SAMs and 8 PGFs examined to produce distinct response patterns for each of 13 analytes. The analytes include aliphatic, aromatic, and chlorinated hydrocarbons; alcohols; ketones; organophosphonates; and water. Evaluation of the SAW array data using multidimensional cluster analysis techniques show that each chemical species can be correctly identified 100% of the time over the 9%- to 49%-of-saturation range using data from many combinations of four or more films.

  20. Improved structure of CdS monolithic SAW convolver with high photoenhancement

    NASA Astrophysics Data System (ADS)

    Ueda, Z.; Shirafuji, J.; Inuishi, Y.

    1980-09-01

    The improved photoenhancement of the SAW convolution effect in monolithic convolvers with high-resistivity surface layer has been discussed. CdS monolithic convolvers with one or a half acoustical wavelength thick high-resistivity layer formed on semiconductive substrate are prepared in order to check the expected behavior. Due to much reduction of the acoustoelectric loss of SAW, the convolver with a half acoustical wavelength thick high-resistivity layer shows a remarkable photoenhancement, 20 times the value in the dark, when photo-carriers are generated uniformly in the high-resistivity layer. Nonlinear capacitance mechanism can also induce photoenhancement of the convolution effect. It is first found that further enhancement of the convolution can be achieved by applying positive pulsed bias to the gate electrode under illumination with a light of high absorption coefficient.

  1. Design and use of multiple blade slurry sawing in a production atmosphere

    NASA Technical Reports Server (NTRS)

    Lynah, F. P., Jr.; Ross, J. B.

    1982-01-01

    The technique and uses of the multiple blade slurry (MBS) saw are considered. Multiple bands of steel are arranged in a frame and the frame is reciprocated with the steel bands to a workpiece, while simultaneously applying abrasive at the point of contact. The blades wear slots in the workpiece and progress through the piece resulting in several parts of wafers. The transition to MBA from diamond slicing is justified by savings resulting from minimized kerf losses, minimized subsurface damage, and improved surface quality off the saw. This allows wafering much closer to finished thickness specifications. The current state of the art MBS technology must be significantly improved if the low cost solar array (LSA) goals are to be attained. It is concluded that although MBS will never be the answer to every wafering requirement, the economical production of wafers to LSA project specifications will be achieved.

  2. Pseudo-orthogonal frequency coded wireless SAW RFID temperature sensor tags.

    PubMed

    Saldanha, Nancy; Malocha, Donald C

    2012-08-01

    SAW sensors are ideal for various wireless, passive multi-sensor applications because they are small, rugged, radiation hard, and offer a wide range of material choices for operation over broad temperature ranges. The readable distance of a tag in a multi-sensor environment is dependent on the insertion loss of the device and the processing gain of the system. Single-frequency code division multiple access (CDMA) tags that are used in high-volume commercial applications must have universal coding schemes and large numbers of codes. The use of a large number of bits at the common center frequency to achieve sufficient code diversity in CDMA tags necessitates reflector banks with >30 dB loss. Orthogonal frequency coding is a spread-spectrum approach that employs frequency and time diversity to achieve enhanced tag properties. The use of orthogonal frequency coded (OFC) SAW tags reduces adjacent reflector interactions for low insertion loss, increased range, complex coding, and system processing gain. This work describes a SAW tag-sensor platform that reduces device loss by implementing long reflector banks with optimized spectral coding. This new pseudo-OFC (POFC) coding is defined and contrasted with the previously defined OFC coding scheme. Auto- and cross-correlation properties of the chips and their relation to reflectivity per strip and reflector length are discussed. Results at 250 MHz of 8-chip OFC and POFC SAW tags will be compared. The key parameters of insertion loss, cross-correlation, and autocorrelation of the two types of frequency-coded tags will be analyzed, contrasted, and discussed. It is shown that coded reflector banks can be achieved with near-zero loss and still maintain good coding properties. Experimental results and results predicted by the coupling of modes model are presented for varying reflector designs and codes. A prototype 915-MHz POFC sensor tag is used as a wireless temperature sensor and the results are shown. PMID:22899121

  3. Some Fundamental Limits on SAW RFID Tag Information Capacity and Collision Resolution

    NASA Technical Reports Server (NTRS)

    Barton, Richard J.

    2013-01-01

    In this paper, we apply results from multi-user information theory to study the limits of information capacity and collision resolution for SAW RFID tags. In particular, we derive bounds on the achievable data rate per tag as a function of fundamental parameters such as tag time-bandwidth product, tag signal-to-noise ratio (SNR), and number of tags in the environment. We also discuss the implications of these bounds for tag waveform design and tag interrogation efficiency

  4. Selective detection of elemental mercury vapor using a surface acoustic wave (SAW) sensor.

    PubMed

    Kabir, K M Mohibul; Sabri, Ylias M; Matthews, Glenn I; Jones, Lathe A; Ippolito, Samuel J; Bhargava, Suresh K

    2015-08-21

    The detection of elemental mercury (Hg(0)) within industrial processes is extremely important as it is the first major step in ensuring the efficient operation of implemented mercury removal technologies. In this study, a 131 MHz surface acoustic wave (SAW) delay line sensor with gold electrodes was tested towards Hg(0) vapor (24 to 365 ppbv) with/without the presence of ammonia (NH3) and humidity (H2O), as well as volatile organic compounds (VOCs) such as acetaldehyde (MeCHO), ethylmercaptan (EM), dimethyl disulfide (DMDS) and methyl ethyl ketone (MEK), which are all common interfering gas species that co-exist in many industrial applications requiring mercury monitoring. The developed sensor exhibited a detection limit of 0.7 ppbv and 4.85 ppbv at 35 and 55 °C, respectively. Furthermore, a repeatability of 97% and selectivity of 92% in the presence of contaminant gases was exhibited by the sensor at the chosen operating temperature of 55 °C. The response magnitude of the developed SAW sensor towards different concentrations of Hg(0) vapor fitted well with the Langmuir extension isotherm (otherwise known as loading ratio correlation (LRC)) which is in agreement with our basic finite element method (FEM) work where an LRC isotherm was observed for a simplified model of the SAW sensor responding to different Hg contents deposited on the Au based electrodes. Overall, the results indicate that the developed SAW sensor can be a potential solution for online selective detection of low concentrations of Hg(0) vapor found in industrial stack effluents. PMID:26065560

  5. Beveled osteotomies in lateral orbitotomy using a customized rotating bone saw for orbital neoplasms.

    PubMed

    Santiago, Maria Donna Damo; Tuano, Prospero Maria

    2015-06-01

    This study aims to develop a novel method of beveled osteotomy for lateral orbitotomy using a customized 21-mm stainless steel rotating saw in lateral orbitotomy and to evaluate the outcome of a novel beveled osteotomy in lateral orbitotomy. This article presents a case series (19 orbits from 18 patients) of lateral orbitotomies for excision biopsy of orbital neoplasms, over a 10-year period (from September 2001 to October 2011). It is a retrospective observational study. The surgeries were performed under the primary service of one surgeon (M. D. D. S.), the author of this study. All patients were treated via beveled osteotomies in lateral orbitotomy using a stainless steel, 21?mm diameter, customized rotating bone saw. Preoperative and postoperative measurements were tabulated and statistically analyzed. The case series demonstrated that beveled osteotomies in lateral orbitotomy using a stainless steel, 21?mm diameter, customized rotating bone saw was technically possible and provided access to lateral subperiorbital, peripheral, and central surgical spaces. The exposure was ample for excision biopsy of all neoplasms in this study. No patient needed the use of miniplate hardware in repositioning the lateral orbital wall nor complained of a palpable deformity of the lateral orbital wall. The wound healing was rapid, with minimal tissue distortion or scars. There were two patients who developed skin burns, but neither required a cosmetic surgery to correct scarring from the burn. It was concluded that the modified technique of beveled osteotomies in lateral orbitotomy provides excellent access to the lateral subperiorbital, peripheral and central surgical spaces. The exposure was adequate for excision biopsy of all neoplasms in this study. The technique promotes osseous union without the use of miniplate hardware. The use of a stainless steel 21?mm diameter customized rotating bone saw facilitated the successful outcome of the beveled technique. PMID:26000087

  6. Mind your hand during the energy crunch: Functional Outcome of Circular Saw Hand Injuries

    PubMed Central

    2010-01-01

    Background Although injuries due to circular saws are very common all over the world, there is surprisingly little information available about their functional outcomes. As the socioeconomic impact of these injuries is immense and determined by the casualties' disability and impairment, it is the objective of this study to present data on the functional outcome, disability, and impairment of hand injuries due to electric circular saws. Methods Patients treated from 1999 through 2007 for circular saw-related hand injuries were contacted and asked for clinical follow-up assessment. The clinical follow-up protocol consisted of a physical examination and an assessment of static muscle power (grip and pinch strength). For assessment of the subjective experience of the patients regarding their injury-related disability and impairment, the DASH follow-up questionnaire was used. The occupational impact of these injuries was measured by number of lost working days. Finally, safety-related behaviour of the patients was investigated. Results 114 Patients were followed-up on average 52 months after the injury. Average in-house treatment was 8.8 days. Average time lost from work was 14.8 weeks. A significant reduction of static muscle testing parameters compared with the uninjured hand was revealed for grip strength, tip pinch, key pinch, and palmar pinch. Average DASH score was 17.4 (DASH work 15.8, DASH sports/music 17.7). Most patients had more than ten years experience in using these power tools. Conclusion The everyday occurrence of circular saw-related hand injuries followed by relatively short periods of in-house treatment might distort the real dimension of the patients' remaining disability and impairment. While the trauma surgeon's view is generally confined to the patients' clinical course, the outcome parameters in this follow-up investigation, with loss of working time as the key factor, confirm that the whole socioeconomic burden is much greater than the direct cost of treatment. PMID:20819215

  7. Advances in SXFA-coated SAW chemical sensors for organophosphorous compound detection.

    PubMed

    Wang, Wen; He, Shitang; Li, Shunzhou; Liu, Minghua; Pan, Yong

    2011-01-01

    A polymer-coated surface acoustic wave (SAW)-based chemical sensor for organophosphorous compound sensing at extremely low concentrations was developed, in which a dual-delay-line oscillator coated with fluoroalcoholpolysiloxane (SXFA) acted as the sensor element. Response mechanism analysis was performed on the SXFA-coated chemical sensor, resulting in the optimal design parameters. The shear modulus of the SXFA, which is the key parameter for theoretical simulation, was extracted experimentally. New designs were done on the SAW devices to decrease the insertion loss. Referring to the new phase modulation approach, superior short-term frequency stability (±2 Hz in seconds) was achieved from the SAW oscillator using the fabricated 300 MHz delay line as the feedback element. In the sensor experiment on dimethylmethylphosphonate (DMMP) detection, the fabricated SXFA-coated chemical sensor exhibited an excellent threshold detection limit up to 0.004 mg/m(3) (0.7 ppb) and good sensitivity (?485 Hz/mg/m(3) for a DMMP concentration of 2?14 mg/m(3)). PMID:22319366

  8. Measurement and FEM/BEM simulation of transverse effects in SAW resonators on lithium tantalate.

    PubMed

    Solal, Marc; Chen, Li; Gratier, Julien

    2013-11-01

    It is well known that transverse effects contribute significantly to the loss of SAW resonators on lithium tantalate. In particular, for frequencies above resonance, the surface wave is not guided inside the transducer and radiates into the busbars. In addition, because bulk modes can also be excited, scalar models are not sufficient to accurately predict transverse effects. It is also known that the layout of a SAW resonator (electrode gaps and dummy electrodes) has a strong impact on the transverse effects. In this paper, a periodic FEM/BEM model is presented and is used to simulate the transverse effects for various SAW resonator layouts. Test devices matching those simulated are fabricated and measured; the measured results are compared with the simulated results and show good agreement. By analyzing the dispersion curves produced from the FEM/BEM model in the different regions of the device, several frequency bands corresponding to different transverse behaviors are identified. These results are consistent with the elastic displacements, also computed by the FEM/BEM model. It is further shown that guided conditions in the gap between the transducer and the busbar occur for a frequency range above resonance. This result is in agreement with measurements showing that resonators with smaller gaps exhibit smaller spurious responses in their admittance. PMID:24158295

  9. An A4-based see-saw model for realistic neutrino mass and mixing

    E-print Network

    Pramanick, Soumita

    2015-01-01

    We present an $A4$-based model where neutrino masses arise from a combination of see-saw mechanisms. The model is motivated by several small mixing and mass parameters indicated by the data. These are $\\theta_{13}$, the solar mass splitting, and the small deviation of $\\theta_{23}$ from maximal mixing (= $\\pi/4$). We take the above as indications that at some level the small quantities are well-approximated by zero. In particular the mixing angles, to a zero order, should be either 0 or $\\pi/4$. Accordingly, in this model the Type-II see-saw dominates and generates the larger atmospheric mass splitting and sets $\\theta_{23} = \\pi/4$. The other mixing angles are vanishing as is the solar splitting. We show how the $A4$ assignment for the lepton doublets leads to this form. We also specify the $A4$ properties of the right-handed neutrinos which result in a smaller Type-I see-saw contribution that acts as a perturbation and shifts the angles $\\theta_{12}$ and $\\theta_{13}$ into the correct range and the desired ...

  10. Sezawa mode SAW pressure sensors based on ZnO/Si structure.

    PubMed

    Talbi, Abdelkrim; Sarry, Frederic; Le Brizoual, Laurent; Elmazria, Omar; Alnot, Patrick

    2004-11-01

    Surface acoustic wave (SAW) devices have been shown to be suitable for many sensor applications. One of these applications is pressure sensor. In this study we investigate the performance of SAW pressure sensors formed with ZnO/Si(001) structure. The pressure sensitivities of Rayleigh mode as well as the Sezawa mode are studied as a function of normalized thickness (kh = 2pihZnO/lambda). The experimental results show an opposite strain effect in the ZnO layer and Si substrate. A theoretical approach based on the perturbation method has been developed for the evaluation of pressure sensitivity in the Sezawa mode. Experimental and theoretical results obtained for the ZnO/Si SAW sensor prepared with kh = 1.18 are in good agreement. For kh < or = 1.2, the ZnO contribution to the sensor sensitivity can be neglected in the Sezawa mode in which ZnO acts mainly as an electromechanical conversion layer. PMID:15600085

  11. Recent developments on surface acoustic wave (SAW) sensors for harsh conditions

    NASA Astrophysics Data System (ADS)

    Schiopu, Paul; Chilibon, Irinela; Grosu, Neculai; Craciun, Alexandru

    2015-02-01

    The results of research into Surface Acoustic Waves (SAW) devices have been recognized for their efficiency and versatility in the electrical signals processing. Actual progress in the industrial application of piezoelectric materials such as Lithium Niobate (LiNbO3), Langasite (LGS), Lanthanum-Gallium Silicate La3Ga5SiO14 and Gallium Orthophosphate (GaPO4), allows the manufacturing of devices with piezoelectric performances, which overcome the limits obtained with quartz crystals. The single crystal materials have a long term high stability - near to infinite - and moreover, some of these have an excellent behavior with temperature variation. Today, GaPO4 with its properties is by far the best suited piezoelectric material to be used in sensor applications for machine monitoring and pressure measurements, at high temperatures. SAW micro devices based on GaPO4 operate at temperatures of up to 8000C. For a particular case, of harsh-environment applications, additional challenges need to be overcome, relating to substrate integrity and operation, thin film electrode fabrication, device packaging, and sensor interrogation. This paper reviews the novel progres in the area of (SAW) sensors for harsh conditions.

  12. Evaluation of Relative Sensitivity of SAW and Flexural Plate Wave Devices for Atmospheric Sensing

    NASA Technical Reports Server (NTRS)

    White, Richard M.; Black, Justin; Chen, Bryan

    1998-01-01

    The objective of this project is to evaluate the suitability of the ultrasonic flexural plate wave (FPW) device as the detector in a gas chromatograph (GC). Of particular interest is the detection of nitrous oxide (N2O). From experimental results we conclude analyte detection is achieved through two mechanisms: changes in gas density, and mass loading of the device membrane due to the sorption of gas molecules. Reducing the dead volume of the FPW chamber increased the FPW response. A comparison of the FPW response to that of the surface acoustic wave (SAW) detector provided with the GC (made by MSI, Microsensor Technologies, Inc.), shows that for unseparated N2O in N2, the FPW exhibits a sensitivity that is at least 550 times greater than that of the SAW device. A Porapak Q column was found to separate N2O from its carrier gas, N2 or He. With the Porapak Q column, a coated FPW detected 1 ppm N2O in N2 or He, with a response magnitude of 7 Hz. A coated SAW exhibited a response of 25 Hz to pure N2O. The minimal detectable N2O concentrations of the sensors were not evaluated.

  13. Maximum Measurement Range and Accuracy of SAW Reflective Delay Line Sensors

    PubMed Central

    Zheng, Zehua; Han, Tao; Qin, Peng

    2015-01-01

    In a surface acoustic wave (SAW) wireless sensor with a reflective delay line structure, three reflectors are often used to eliminate 2? ambiguity of phase measurement. The maximum range of the measured parameter and the maximum accuracy have recently been attracting much research attention. In this paper, an analytical formula for all the factors influencing the measurement range and accuracy of the delay line SAW sensor are deduced for the first time. The factors include: the sensor sensitivity, the topology of the delay line, the available wireless bandwidth and the allowed maximum phase measuring error of the reading system, which is easier to retrieve and more fully describes the possible noises than SNR. Additionally, many designers believe that increasing the reflector could improve accuracy continuously or realize multi-resolution measurement. However, they ignore some certain criteria that the reflector location must satisfy. The reachable maximum accuracy by every increase of a reflector is also presented. A SAW temperature sensor system using 128° YX-LiNbO3 is designed to verify the above theoretical analysis. PMID:26492251

  14. Surface morphology of ultrathin graphene oxide films obtained by the SAW atomization

    NASA Astrophysics Data System (ADS)

    Balachova, Olga V.; Balashov, Sergey M.; Costa, Carlos A. R.; Pavani Filho, A.

    2015-08-01

    Lately, graphene oxide (GO) thin films have attracted much attention: they can be used as humidity-sensitive coatings in the surface acoustic wave (SAW) sensors; being functionalized, they can be used in optoelectronic or biodevices, etc. In this research we study surface morphology of small-area thin GO films obtained on Si and quartz substrates by deposition of very small amounts of H2O-GO aerosols produced by the SAW atomizer. An important feature of this method is the ability to work with submicrovolumes of liquids during deposition that provides relatively good control over the film thickness and quality, in particular, minimization of the coffee ring effect. The obtained films were examined using AFM and electron microscopy. Image analysis showed that the films consist of GO sheets of different geometry and sizes and may form discrete or continuous coatings at the surface of the substrates with the minimum thickness of 1.0-1.8 nm which corresponds to one or two monolayers of GO. The thickness and quality of the deposited films depend on the parameters of the SAW atomization (number of atomized droplets, a volume of the initial droplet, etc.) and on sample surface preparation (activation in oxygen plasma). We discuss the structure of the obtained films, uniformity and the surface coverage as a function of parameters of the film deposition process and sample preparation. Qualitative analysis of adhesion of GO films is made by rinsing the samples in DI water and subsequent evaluation of morphology of the remained films.

  15. Saw cuts in unicompartmental knee arthroplasty: an analysis of Sawbone preparations.

    PubMed

    Clarius, Michael; Aldinger, Peter R; Bruckner, Thomas; Seeger, Joern B

    2009-10-01

    Unicompartmental knee arthroplasty (UKA) has become a frequently used treatment option for anteromedial osteoarthritis (OA) of the knee due to good clinical and functional results. However, serious complications like tibial plateau fractures have been reported. These can be associated with saw cuts during surgery. The purpose of this study was to analyse saw cuts during Sawbone preparations at instructional unicompartmental knee courses and to identify potential sources of surgical error. One hundred Sawbone preparations were performed by knee surgeons inexperienced with UKA. Sawing errors during preparation were analysed and quantified. Tibial and femoral errors can occur during preparation. At the proximal tibia three errors can be found: extended vertical cuts (A), extended horizontal cuts (B) and perforation of the posterior cortex. An ascending cut at the posterior femoral condyle (C) is possible during femoral preparation. Errors type A were found at a mean length of 2.4 mm+/-2.3 mm with a maximum value of 10.1 mm. In 18% errors of more than 4.0 mm were found. Type B errors showed an average value of 2.0 mm+/-1.7 mm with maximum values of 7.4 mm. Type C errors were found at a mean of 1.3 mm+/-1.0 mm (maximum value 5.1 mm). Our data showed that in 18% of the cases, vertical cutting errors of more than 4.0 mm occurred in inexperienced surgeons. PMID:19196514

  16. Rounded cutting edge model for the prediction of bone sawing forces.

    PubMed

    James, Thomas P; Pearlman, John J; Saigal, Anil

    2012-07-01

    A new analytical model to predict bone sawing forces is presented. Development of the model was based on the concept of a single tooth sawing at a depth of cut less than the cutting edge radius. A variable friction model was incorporated as well as elastic Hertzian contact stress to determine a lower bound for the integration limits. A new high speed linear apparatus was developed to simulate cutting edge speeds encountered with sagittal and reciprocating bone saws. Orthogonal cutting experiments in bovine cortical bone were conducted for comparison to the model. A design of the experiment's approach was utilized with linear cutting speeds between 2600 and 6200 mm/s for depths of cut between 2.5 and 10 ?m. Resultant forces from the design of experiments were in the range of 8 to 11 N, with higher forces at greater depths of cut. Model predictions for resultant force magnitude were generally within one standard deviation of the measured force. However, the model consistently predicted a thrust to cutting force ratio that was greater than measured. Consequently, resultant force angles predicted by the model were generally 20 deg higher than calculated from experimental thrust and cutting force measurements. PMID:24763623

  17. Detection, Identification, Location, and Remote Sensing Using SAW RFID Sensor Tags

    NASA Technical Reports Server (NTRS)

    Barton, Richard J.; Kennedy, Timothy F.; Williams, Robert M.; Fink, Patrick W.; Ngo, Phong H.

    2009-01-01

    The Electromagnetic Systems Branch (EV4) of the Avionic Systems Division at NASA Johnson Space Center in Houston, TX is studying the utility of surface acoustic wave (SAW) radiofrequency identification (RFID) tags for multiple wireless applications including detection, identification, tracking, and remote sensing of objects on the lunar surface, monitoring of environmental test facilities, structural shape and health monitoring, and nondestructive test and evaluation of assets. For all of these applications, it is anticipated that the system utilized to interrogate the SAW RFID tags may need to operate at fairly long range and in the presence of considerable multipath and multiple-access interference. Towards that end, EV4 is developing a prototype SAW RFID wireless interrogation system for use in such environments called the Passive Adaptive RFID Sensor Equipment (PARSED) system. The system utilizes a digitally beam-formed planar receiving antenna array to extend range and provide direction-of-arrival information coupled with an approximate maximum-likelihood signal processing algorithm to provide near-optimal estimation of both range and temperature. The system is capable of forming a large number of beams within the field of view and resolving the information from several tags within each beam. The combination of both spatial and waveform discrimination provides the capability to track and monitor telemetry from a large number of objects appearing simultaneously within the field of view of the receiving array. In this paper, we will consider the application of the PARSEQ system to the problem of simultaneous detection, identification, localization, and temperature estimation for multiple objects. We will summarize the overall design of the PARSEQ system and present a detailed description of the design and performance of the signal detection and estimation algorithms incorporated in the system. The system is currently configured only to measure temperature (jointly with range and tag ID), but future versions will be revised to measure parameters other than temperature as SAW tags capable of interfacing with external sensors become available. It is anticipated that the estimation of arbitrary parameters measured using SAW-based sensors will be based on techniques very similar to the joint range and temperature estimation techniques described in this paper.

  18. Thin, High Lifetime Silicon Wafers with No Sawing; Re-crystallization in a Thin Film Capsule

    SciTech Connect

    Emanuel Sachs Tonio Buonassisi

    2013-01-16

    The project fits within the area of renewable energy called photovoltaics (PV), or the generation of electricity directly from sunlight using semiconductor devices. PV has the greatest potential of any renewable energy technology. The vast majority of photovoltaic modules are made on crystalline silicon wafers and these wafers accounts for the largest fraction of the cost of a photovoltaic module. Thus, a method of making high quality, low cost wafers would be extremely beneficial to the PV industry The industry standard technology creates wafers by casting an ingot and then sawing wafers from the ingot. Sawing rendered half of the highly refined silicon feedstock as un-reclaimable dust. Being a brittle material, the sawing is actually a type of grinding operation which is costly both in terms of capital equipment and in terms of consumables costs. The consumables costs associated with the wire sawing technology are particularly burdensome and include the cost of the wire itself (continuously fed, one time use), the abrasive particles, and, waste disposal. The goal of this project was to make wafers directly from molten silicon with no sawing required. The fundamental concept was to create a very low cost (but low quality) wafer of the desired shape and size and then to improve the quality of the wafer by a specialized thermal treatment (called re-crystallization). Others have attempted to create silicon sheet by recrystallization with varying degrees of success. Key among the difficulties encountered by others were: a) difficulty in maintaining the physical shape of the sheet during the recrystallization process and b) difficulty in maintaining the cleanliness of the sheet during recrystallization. Our method solved both of these challenges by encapsulating the preform wafer in a protective capsule prior to recrystallization (see below). The recrystallization method developed in this work was extremely effective at maintaining the shape and the cleanliness of the wafer. In addition, it was found to be suitable for growing very large crystals. The equipment used was simple and inexpensive to operate. Reasonable solar cells were fabricated on re-crystallized material.

  19. Saw Palmetto

    MedlinePLUS

    ... hard-of-hearing callers): 1-866-464-3615 Web site: nccih.nih.gov E-mail: info@nccih. ... summaries of articles from scientific and medical journals. Web site: www.ncbi.nlm.nih.gov/pubmed Office ...

  20. Deep-UV sensors based on SAW oscillators using low-temperature-grown AlN films on sapphires.

    PubMed

    Laksana, Chipta; Chen, Meei-Ru; Liang, Yen; Tzou, An-Jyeg; Kao, Hui-Ling; Jeng, Erik; Chen, Jyh; Chen, Hou-Guang; Jian, Sheng-Rui

    2011-08-01

    High-quality epitaxial AlN films were deposited on sapphire substrates at low growth temperature using a helicon sputtering system. SAW filters fabricated on the AlN films exhibited excellent characteristics, with center frequency of 354.2 MHz, which corresponds to a phase velocity of 5667 m/s. An oscillator fabricated using AlN-based SAW devices is presented and applied to deep-UV light detection. A frequency downshift of about 43 KHz was observed when the surface of SAW device was illuminated by a UV source with dominant wavelength of around 200 nm. The results indicate the feasibility of developing remote sensors for deep-UV measurement using AlN-based SAW oscillators. PMID:21859589

  1. Chemically sensitive polymer-mediated nanoporous alumina SAW sensors for the detection of vapor-phase analytes 

    E-print Network

    Perez, Gregory Paul

    2005-08-29

    We have investigated the chemical sensitivity of nanoporous (NP) alumina-coated surface acoustic wave (SAW) devices that have been surface-modified with polymeric mediating films. The research in this dissertation covers the refinement of the NP...

  2. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - ADAMANT CIRCULAR SAW OENHP{number_sign}: 2001-05, VERSION A

    SciTech Connect

    Unknown

    2002-01-01

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting up specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactive contaminated glove boxes at the Department of Energy's (DOE) Los Alamos facility. The Adamant circular saw was assessed on August 14, 2001. During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Adamant was only used during a limited ''test'' on a regular plywood crate due to safety considerations of the tool for this application. The Adamant circular saw, a counter-rotating twin-cutter, constructed with blades that work differently than conventional cutting wheels with twin blades, each rotating in opposite directions. It is used to cut wood and metals. Each blade is approximately 8 3/4 inches in diameter with a maximum cutting depth of 2 1/2 inches. The machine has two rotation speeds: 1,900 and 2,900 rotations per minute (rpm). The saw is operated with an interlocked, guarded trigger switch located at the end of the saw opposite the cutting blades. To operate the saw, the safety interlock must be depressed prior to powering the saw with the trigger control. The saw is supported by a handle at the front of the saw near the cutting blades. The top part of the blades is guarded near the handle, with approximately three-fourths of the face of the blades exposed. The Adamant circular saw is an innovative technology used to cut metals and wood. Its safety features include: interlocking switch for powering the saw, overload indicator and shutoff, and an electronic brake that stops the engine immediately when the start button is released. The top part of the blades is guarded near the motor. With approximately three-fourths of the face of the blades open, the operator is exposed to the potential risk of serious and minor cuts and abrasions when using and handling the saw. There is also potential for damage to the blades if the saw is not stored properly. Without guarding on the lower part of the blades, these can be damaged if the saw is dropped or rested on the cutting blades. Based upon the industrial hygiene sampling conducted for the other four saws demonstrated at FIU, noise levels, nuisance dust, and airborne fiberglass may be a problem when using this technology for the cutting of fiberglass-reinforced plywood crates. No industrial hygiene sampling was conducted while the Adamant saw was in use. Engineering controls should be used to eliminate these problems whenever possible. Where this is not possible, administrative controls, training, and proper personal protective equipment (PPE) should be used. Respirators should be used if engineering controls do not sufficiently control the dust or fiberglass generated. Respirators should be equipped with an organic vapor and acid gas cartridge with High Efficiency Particulate Air (HEPA) filter, since during the demonstration, the workers complained of an odd smell, which may have been the breakdown of the fiberglass.

  3. Prototype of Cutting Machine by Wire-sawing in Vacuum for In-Situ Investigation of Rocks

    NASA Astrophysics Data System (ADS)

    Furutani, K.; Ikeda, E.; Okada, T.; Saiki, K.; Ohue, H.

    2009-03-01

    Cutting characteristics of rocks in air and vacuum were investigated for the preprocess of the scientific inspection. The machining amount of basalt with a wire saw in vacuum was saturated in a short time due to loading of pulverized debris.

  4. Piezoelectric shunt damping of a circular saw blade with autonomous power supply for noise and vibration reduction

    NASA Astrophysics Data System (ADS)

    Pohl, Martin; Rose, Michael

    2016-01-01

    Circular saws are widespread tools for machining metal, wood or even ceramics. Due to the thin blade and excitation by the workpiece contact of the cutting edges, circular saws are prone to vibration and intense noise emission. Damping the blade will lower the hearing protection requirements of the users and possibly increase precision. Therefore a new damping concept for circular saw blades is presented in this paper. It is based on negative capacitance shunted piezoelectric transducers which are applied to the saw blade core. The required energy for the electronics is harvested from the rotation by a generator, so that no change of the machine tool is required. All components are integrated into an autonomous saw tool. Finally, the system is experimentally investigated without rotation, in idling and in cutting condition in a circular saw test stand in the Institute for Machine Tools and Production Engineering (IWF) at TU Braunschweig. The experimental investigation shows a good reduction of the vibration amplitude over a wide frequency range in the non-rotating condition. When rotating, the damping effect is lower and limited to some narrow frequency bands. The proposed reason for the reduced damping effect in rotating condition consists in the saturation of the electronic circuits due to the limited supply voltage capabilities.

  5. iSAW: Integrating Structure, Actors, and Water to study socio-hydro-ecological systems

    NASA Astrophysics Data System (ADS)

    Hale, Rebecca L.; Armstrong, Andrea; Baker, Michelle A.; Bedingfield, Sean; Betts, David; Buahin, Caleb; Buchert, Martin; Crowl, Todd; Dupont, R. Ryan; Ehleringer, James R.; Endter-Wada, Joanna; Flint, Courtney; Grant, Jacqualine; Hinners, Sarah; Horsburgh, Jeffery S.; Jackson-Smith, Douglas; Jones, Amber S.; Licon, Carlos; Null, Sarah E.; Odame, Augustina; Pataki, Diane E.; Rosenberg, David; Runburg, Madlyn; Stoker, Philip; Strong, Courtenay

    2015-03-01

    Urbanization, climate, and ecosystem change represent major challenges for managing water resources. Although water systems are complex, a need exists for a generalized representation of these systems to identify important components and linkages to guide scientific inquiry and aid water management. We developed an integrated Structure-Actor-Water framework (iSAW) to facilitate the understanding of and transitions to sustainable water systems. Our goal was to produce an interdisciplinary framework for water resources research that could address management challenges across scales (e.g., plot to region) and domains (e.g., water supply and quality, transitioning, and urban landscapes). The framework was designed to be generalizable across all human-environment systems, yet with sufficient detail and flexibility to be customized to specific cases. iSAW includes three major components: structure (natural, built, and social), actors (individual and organizational), and water (quality and quantity). Key linkages among these components include: (1) ecological/hydrologic processes, (2) ecosystem/geomorphic feedbacks, (3) planning, design, and policy, (4) perceptions, information, and experience, (5) resource access and risk, and (6) operational water use and management. We illustrate the flexibility and utility of the iSAW framework by applying it to two research and management problems: understanding urban water supply and demand in a changing climate and expanding use of green storm water infrastructure in a semi-arid environment. The applications demonstrate that a generalized conceptual model can identify important components and linkages in complex and diverse water systems and facilitate communication about those systems among researchers from diverse disciplines.

  6. Effect of operating parameters on the removal of bone cement by a sawing process.

    PubMed

    James, Thomas P; Sheehan, Brian; Sagar, Amrit

    2014-03-01

    The number of total knee arthroplasty revision surgeries is increasing each year, driven by the wide availability and general acceptance of the procedure accompanied by an aging population of implants. Metal implants are often secured to the tibial plateau by a mantle of poly(methyl methacrylate) bone cement. During revision surgery, a power oscillating saw is used to remove bone cement while preparing the boney bed. Presently, there are no published studies on the mechanics of bone cement removal by a sawing process. The aim of this research was to quantify the effect of blade speed and applied thrust force on the volumetric cutting rate of bone cement. A custom reciprocating saw with variable stroke length was used to conduct a three-factor design of experiments. Two levels, without center-points, were sufficient to model the effect of stroke length (6.75, 10.13 mm), thrust force (11, 19 N), and reciprocating speed in strokes per minute (6000, 8000 SPM) on cutting rate. The results indicate that each of the three parameters had a significant impact on cutting rate (p < 0.001), with a linear relationship between both force and cutting rate (r = 0.98) and blade speed and cutting rate (r = 0.98). For the parameters considered, increasing the reciprocating speed had the most significant effect on cutting rate. For example, while holding force and stroke length constant (11 N, 10.13 mm), an increase in speed from 6000 to 8000 SPM nearly doubled the cutting rate of bone cement. A cutting rate model was developed by regression analysis of the experimental data and validated through additional experiments. The model has applications in haptic feedback for surgical simulators to differentiate between the cutting rates of bone and bone cement during virtual training of resident surgeons. PMID:24562099

  7. Achievable Performance and Effective Interrogator Design for SAW RFID Sensor Tags

    NASA Technical Reports Server (NTRS)

    Barton, Richard J.

    2011-01-01

    For many NASA missions, remote sensing is a critical application that supports activities such as environmental monitoring, planetary science, structural shape and health monitoring, non-destructive evaluation, etc. The utility of the remote sensing devices themselves is greatly increased if they are passive that is, they do not require any on-board power supply such as batteries and if they can be identified uniquely during the sensor interrogation process. Additional passive sensor characteristics that enable greater utilization in space applications are small size and weight, long read ranges with low interrogator power, ruggedness, and operability in extreme environments (vacuum, extreme high/low temperature, high radiation, etc.) In this paper, we consider one very promising passive sensor technology, called surface acoustic wave (SAW) radio-frequency identification (RFID), that satisfies all of these criteria. Although SAW RFID tags have great potential for use in numerous space-based remote sensing applications, the limited collision resolution capability of current generation tags limits the performance in a cluttered sensing environment. That is, as more SAW-based sensors are added to the environment, numerous tag responses are superimposed at the receiver and decoding all or even a subset of the telemetry becomes increasingly difficult. Background clutter generated by reflectors other than the sensors themselves is also a problem, as is multipath interference and signal distortion, but the limiting factor in many remote sensing applications can be expected to be tag mutual interference. This problem may be greatly mitigated by proper design of the SAW tag waveform, but that remains an open research problem, and in the meantime, several other related questions remain to be answered including: What are the fundamental relationships between tag parameters such as bit-rate, time-bandwidth-product, SNR, and achievable collision resolution? What are the differences in optimal or near-optimal interrogator designs between noise-limited environments and interference-limited environments? What are the performance characteristics of different interrogator designs in term of parameters such as transmitter power level, range, and number of interfering tags? In this paper, we present the results of a research effort aimed at providing at least partial answers to all of these questions.

  8. Sensitivities of SAW oscillators to temperature, forces and pressure Application to sensors

    NASA Astrophysics Data System (ADS)

    Hauden, D.; Rousseau, S.; Gagnepain, J. J.

    The sensitivity of SAW oscillators to external thermal and mechanical perturbations is examined. A method is presented, which calculates the static bias in the thin plate approximation by means of Mindlin's polynomial method, and calculates the nonlinear coupling coefficients. Temperature, force and pressure sensors are studied, and influences of bending and uniaxial forces on rectangular quartz-plates, and of diametrically applied forces on circular plates as a function of the azimuthal angle are examined. The sensitivity to hydrostatic pressure is also investigated in the cases of bulky plates and a thin diaphragm. It is found that when plate sensitivity is small, the diaphragm exhibits very large frequency shifts.

  9. Self-avoiding-walks (SAW's) on diluted lattices, a Monte Carlo analysis

    NASA Astrophysics Data System (ADS)

    Kremer, Kurt

    1981-06-01

    A Monte Carlo study of SAW's on a diluted diamond lattice is presented. We find that the exponent v does not change by dilution, v?0.59 as in the undiluted case, in contrast to the original conclusion of Chakrabarti and Kertész. This result cannot be understood by the Harris criterion. At the percolation concentration p c of the lattice we find a higher exponent v pc ?2/3. A scaling form of the crossover between these exponents near p c is proposed and found to be consistent with the Monte Carlo results.

  10. Exotic see-saw mechanism for neutrini and leptogenesis in a Pati-Salam model

    E-print Network

    Addazi, Andrea; Ricciardi, Giulia

    2015-01-01

    We discuss non-perturbative corrections to the neutrino sector, in the context of a D-brane Pati-Salam-like model, that can be obtained as a simple alternative to $SO(10)$ GUT's in theories with open and unoriented strings. In such D-brane models, exotic stringy instantons can correct the right-handed neutrino mass matrix in a calculable way, thus affecting mass hierarchies and modifying the see-saw mechanism to what we name exotic see-saw. For a wide range of parameters, a compact spectrum of right-handed neutrino masses can occur that gives rise to a predictive scenario for low energy observables. This model also provides a viable mechanism for Baryon Asymmetry in the Universe (BAU) through leptogenesis. Finally, a Majorana mass for the neutron is naturally predicted in the model, leading to potentially testable neutron-antineutron oscillations. Combined measurements in neutrino and neutron-antineutron sectors could provide precious informations on physics at the quantum gravity scale.

  11. Safety and security monitoring of dams using nano-micromachined-based surface acoustic wave (SAW) sensors

    NASA Astrophysics Data System (ADS)

    Ross, Wayne, Jr.; Saafi, Mohamed; Romine, Peter; Xiao, Zhigang; Pett, Dave

    2006-03-01

    Concerns about the safety of concrete dams have increased during recent years, partly because the population at risk in locations downstream of major dams continues to expand and also because these old dams are experiencing long-term damage and the seismic design concepts used to build them were inadequate. Reliable techniques for continuous monitoring of certain key parameters affecting the dams' integrity are currently nonexistent and this is because of the lack of sensing technology capable to function in a hostile environment such as low temperatures and high moisture level. This paper presents new low cost, passive and wireless micro-machined SAW-based sensors to monitor the safety and security of dams. These SAW sensors are composed of MEMS transducers, Nano-polymer actuators and an antenna, and are deposited on a thin film substrate. The sensors are passive, do not require power on-board and can be interrogated wireless using a radar. When embedded into concrete dams, the devices will be able to detect and locate internal cracks and measure certain key parameters affecting the durability of dams such as temperature, moisture, pH, chloride and carbon dioxide.

  12. A novel 440 MHz wireless SAW microsensor integrated with pressure temperature sensors and ID tag

    NASA Astrophysics Data System (ADS)

    Lee, Keekeun; Wang, Wen; Kim, Taehyun; Yang, Sangsik

    2007-03-01

    This paper presents the development of a 440 MHz range surface acoustic wave (SAW)-based microsensor integrated with pressure-temperature sensors and ID tag. Two piezoelectric substrates were bonded, in which a ~150 µm air gap was structured by metal poles. The pressure sensor was placed on the top substrate, whereas the ID tag and temperature sensor were located on the bottom substrate. Coupling of modes (COM) modeling was used to find optimal design parameters. Using the extracted optimal design parameters, the SAW device was fabricated. In wireless device testing using a network analyzer, sharp reflection peaks with high S/N ratio, small signal attenuation and small spurious peaks were observed in the time domain. All the reflection peaks were well matched with the predicted values from the simulation. With 10 mW RF power from the network analyzer, a ~1 m readout distance was observed. Depending on applied external pressure, the phase shifts of the reflection peaks were linearly varied. The evaluated sensitivity was about ~2.9° kPa-1. Eight sharp ON reflection peaks were observed for the ID tag. The temperature sensor was characterized from 20 °C to 200 °C. A large phase shift per unit temperature change was observed.

  13. SAW-based fluid atomization using mass-producible chip devices.

    PubMed

    Winkler, A; Harazim, S M; Menzel, S B; Schmidt, H

    2015-09-21

    Surface acoustic wave (SAW)-based fluid atomizers are ideally suited to generate micrometer-sized droplets without any moving parts or nozzles. Versatile application fields can be found for instance in biomedical, aerosol or thin film technology, including medical inhalators or particle deposition for advanced surface treatment. Such atomizers also show great potential for on-chip integration and can lead to economic production of hand-held and even disposable devices, with either a single functionality or integrated in more complex superior systems. However, this potential was limited in the past by fluid supply mechanisms inadequate for mass production, accuracy and reliability. In this work, we briefly discuss existing fluid supply methods and demonstrate a straightforward new approach suited for reliable and cost-effective mass-scale manufacturing of SAW atomizer chips. Our approach is based on a fluid supply at the boundary of the acoustic beam via SU-8 microchannels produced by a novel one-layer/double-exposure photolithography method. Using this technique, we demonstrate precise and stable fluid atomization with almost ideal aerosol plume geometry from a dynamically stabilized thin fluid film. Additionally, we demonstrate the possibility of in situ altering the droplet size distribution by controlling the amount of fluid available in the active region of the chip. PMID:26262577

  14. Lepton Number Violation in TeV Scale See-Saw Extensions of the Standard Model

    E-print Network

    A. Ibarra; E. Molinaro; S. T. Petcov

    2011-02-02

    The low-energy neutrino physics constraints on the TeV scale type I see-saw scenarios of neutrino mass generation are revisited. It is shown that lepton charge (L) violation, associated to the production and decays of heavy Majorana neutrinos N_{j} having masses in the range of M_j \\sim (100 \\div 1000) GeV and present in such scenarios, is hardly to be observed at ongoing and future particle accelerator experiments, LHC included, because of very strong constraints on the parameters and couplings responsible for the corresponding |\\Delta L| = 2 processes. If the heavy Majorana neutrinos N_j are observed and they are associated only with the type I mechanism, they will behave effectively like pseudo-Dirac fermions. Conversely, the observation of effects proving the Majorana nature of N_j would imply that these heavy neutrinos have additional relatively strong couplings to the Standard Model particles or that light neutrino masses compatible with the observations are generated by a mechanism other than see-saw (e.g., radiatively at one or two loop level) in which the heavy Majorana neutrinos N_j are nevertheless involved.

  15. Approximate Green's function representations for the analysis of SAW and leaky wave devices.

    PubMed

    Peach, Robert C

    2009-10-01

    The Green's function or boundary element method (BEM) is the preferred technique for rigorous SAW device analysis. However, because of its computational cost, its principal application is the analysis of mode propagation in periodic structures to determine parameters that can then be used in simplified coupling of modes (COM) or P-matrix models. In this paper, rigorous representations are derived that express the Green's function in terms of a continuous superposition of modes. The derivations include detailed analysis of the Green's function properties as a function of both frequency and wavenumber, and representations are obtained for both the slowness and spatial domains. Approximate forms are then generated by replacing the continuous mode superposition by a discrete one. The Green's function can be approximated to any required degree of accuracy, and the resulting approximations are applicable to any type of wave on any type of substrate. The long-range spatial components in the approximate forms are represented by exponential terms. The separable properties of these terms allow this class of approximation to be applied to general SAW and leaky wave device analysis in such a way that the computational effort increases only linearly with device size. PMID:19942513

  16. SoilSaw{trademark} demonstration. Final report, September 1992--January 1995

    SciTech Connect

    Saugier, K.; Isaac, R.E.

    1996-02-01

    The US Department of Energy (DOE) has identified leaking underground storage tanks and buried mixed waste at numerous sites within the DOE complex. Preventing these wastes from entering the environment is a challenging task. One method of preventing waste migration is to isolate the contaminants using subsurface containment barriers. Isolation and containment can be accomplished by both in situ and ex situ methods. This report describes a novel in situ construction method of forming vertical containment barriers (slurry walls) using the SoilSaw{trademark} Barrier System. The SoilSaw{trademark} Barrier System is shown to be a feasible process for constructing subsurface vertical containment barriers to depths of fifty feet. The process is most efficient in sandy soil (including free flowing sand) with barrier construction rates of over 130 square feet per minute. Productivity diminishes to approximately 30 square feet per minute as soils become harder and more cohesive. The present hardware is designed to form a barrier of approximately 12 inch in width. Additional barrier widths can be constructed with this technology by application of wider jet heads. The requirement for a varied arrangement of barrier widths is an increase in hydraulic horse power and additional jet heads.

  17. SAW arrays using dendrimers and pattern recognition to detect volatile organics

    SciTech Connect

    Ricco, A.J.; Osbourn, G.C.; Bartholomew, J.W.; Martinez, R.F.; Crooks, R.M.; Garcia, M.E.; Peez, R.; Spindler, R.; Kaiser, M.E.

    1998-08-01

    chemical sensor arrays eliminate the need to develop a high-selectivity material for every analyte. The application of pattern recognition to the simultaneous responses of different microsensors enables the identification and quantification of multiple analytes with a small array. Maximum materials diversity is the surest means to create an effective array for many analytes, but using a single material family simplifies coating development. Here the authors report the successful combination of an array of six dendrimer films with mass-sensitive SAW (surface acoustic wave) sensors to correctly identify 18 organic analytes over wide concentration ranges, with 99.5% accuracy. The set of materials for the array is selected and the results evaluated using Sandia`s Visual-Empirical Region of Influence (VERI) pattern recognition (PR) technique. The authors evaluated eight dendrimer films and one self-assembled monolayer (SAM) as potential SAW array coatings. The 18 organic analytes they examined were: cyclohexane, n-hexane, i-octane, kerosene, benzene, toluene, chlorobenzene, carbon tetrachloride, trichloroethylene, methanol, n-propanol, pinacolyl alcohol, acetone, methyl isobutyl ketone, dimethylmethylphosphate, diisopropylmethylphosphonate, tributylphosphate, and water.

  18. Buzz-saw noise : propagation of shock waves in aero-engine inlet ducts

    NASA Astrophysics Data System (ADS)

    Fernando, Rasika; Marchiano, Régis; Coulouvrat, François; Druon, Yann

    2008-06-01

    For supersonic flows relative to turbo-engine fan blades, measured acoustic spectra near the inlet present tones at fan blade passing frequency (BPF), engine shaft rotation frequency, or Engine Order (EO), and their respective harmonics. The latter are responsible for the Buzz-saw noise and are thus referred to as "Buzz-saw" or "multiple pure" tones. This work first attempts to reformulate McAlpine and Fisher's frequency domain model (2001) for the propagation of a unidimensional sawtooth waveform spiralling inside a hard-walled cylindrical duct in the presence of a uniform flow. The non-dissipative Burgers equation is solved using a shock fitting method, and modal attenuation and dispersion are added using a split-step computational method. In practice, shocks do not only occur at blade tips but on a significant portion of the blade span. The plane wave hypothesis being no longer valid, a new three dimensional model is required. This model is based on the computation of the axially varying amplitudes of the modal solutions, in order to take into account the nonlinear modal interactions.

  19. Design and fabrication of passive wireless sensor array system using composite coding resonant SAW transducer

    NASA Astrophysics Data System (ADS)

    Li, Ping; Wen, Yumei

    2006-02-01

    This paper presents a novel composite SAW (surface acoustic wave) passive wireless sensor system involving a resonator and a delay line. While the interrogational signal is a sinusoidal burst, the response is a delayed and damped oscillation. The frequency and the delay time of response are related to the measurand and the coding of the sensor element, respectively. The composite sensor consists of a SAW resonator and a delay line. It combines the advantages of these two devices and can be used as elements of multiple sensors for longer distance passive wireless measurements. As the wireless sensing response is weak and transient, in order to get the response with the maximum signal-to-noise ratio, the interrogational frequency is designed to be adjustable according to the result of frequency estimation. As a result, an optimal sensing result is achieved. In the transceiver set-up, the software DDS (direct digital synthesis) source with a rather high resolution is implemented to track the passive wireless sensor. An isolated switch is set in transmitter to depress the correlation leakage noise after switching off the wireless RF (radio frequency) interrogation signal. In this paper, the characteristics of the response, the working procedure of the signal processing, sensor temperature test results and the system error analyses are elaborated. A prototype instrument is built. Experimental results show the effectiveness of the instrumentation and the advantages of the composite sensor system.

  20. Occupational Injuries in Ohio Wood Product Manufacturing: A Descriptive Analysis With Emphasis on Saw-Related Injuries and Associated Causes

    PubMed Central

    Beery, Lindsay; Harris, James R.; Collins, James W.; Current, Richard S.; Amendola, Alfred A.; Meyers, Alysha R.; Wurzelbacher, Steven J.; Lampl, Mike; Bertke, Stephen J.

    2015-01-01

    Background Stationary sawing machinery is often a basic tool in the wood product manufacturing industry and was the source for over 2,500 injury/illness events that resulted in days away from work in 2010. Methods We examined 9 years of workers’ compensation claims for the state of Ohio in wood product manufacturing with specific attention to saw-related claims. For the study period, 8,547 claims were evaluated; from this group, 716 saw-related cases were examined. Results The sawmills and wood preservation sub-sector experienced a 71% reduction in average incidence rate and an 87% reduction in average lost-time incidence rate from 2001 to 2009. The top three injury category descriptions for lost-time incidents within saw-related claims were fracture (35.8%), open wounds (29.6%), and amputation (14.8%). Conclusions For saw-related injuries, preventing blade contact remains important but securing the work piece to prevent kickback is also important. PMID:25123487

  1. Achievable Performance and Effective Interrogator Design for SAW RFID Sensor Tags

    NASA Technical Reports Server (NTRS)

    Barton Richard J.

    2012-01-01

    For many NASA missions, remote sensing is a critical application that supports activities such as environmental monitoring, planetary science, structural shape and health monitoring, non-destructive evaluation, etc. The utility of the remote sensing devices themselves is greatly increased if they are passive V that is, they do not require any on-board power supply such as batteries V and if they can be identified uniquely during the sensor interrogation process. Additional passive sensor characteristics that enable greater utilization in space applications are small size and weight, long read ranges with low interrogator power, ruggedness, and operability in extreme environments (vacuum, extreme high/low temperature, high radiation, etc.) In this paper, we consider one very promising passive sensor technology, called surface acoustic wave (SAW) radio-frequency identification (RFID), that satisfies all of these criteria. In general, RFID is a method of identifying items using radio waves to interrogate tags encoded with a unique identifier that are affixed to the items of interest. In the case of passive tags, only the interrogator, which transmits power to the tags in the form of radio-frequency electromagnetic radiation, requires access to a power supply. Passive RFID technologies are used today in many applications, including asset tracking and management, security and access control, and remote sensing. To date, most of the development and application in RFID technology has focused on either asset/inventory tracking and control or security and access control because these are the largest commercial application areas. Recently however, there has been growing interest in using passive RFID technology for remote sensing applications, and SAW devices are at the forefront of RFID sensing technology development. Although SAW RFID tags have great potential for use in numerous space-based remote sensing applications, the limited collision resolution capability of current generation tags limits the performance in a cluttered sensing environment. That is, as more SAW-based sensors are added to the environment, numerous tag responses are superimposed at the receiver and decoding all or even a subset of the telemetry becomes increasingly difficult. Background clutter generated by reflectors other than the sensors themselves is also a problem, as is multipath interference and signal distortion, but the limiting factor in many remote sensing applications can be expected to be tag mutual interference. This problem may be greatly mitigated by proper design of the SAW tag waveform, but that remains an open research problem, and in the meantime, several other related questions remain to be answered including: (1) What are the fundamental relationships between tag parameters such as bit-rate, time-bandwidth-product, SNR, and achievable collision resolution? (2) What are the differences in optimal or near-optimal interrogator designs between noise-limited environments and interference-limited environments? (3) What are the performance characteristics of different interrogator designs in term of parameters such as transmitter power level, range, and number of interfering tags? In this paper, we will present the results of a research effort aimed at providing at least partial answers to all of these questions.

  2. A numerical method to derive accurate temperature coefficients of material constants from high-temperature SAW measurements: application to langasite.

    PubMed

    Nicolay, Pascal; Aubert, Thierry

    2013-10-01

    The design of wireless SAW sensors for high-temperature applications requires accurate knowledge of the constitutive materials' physical properties in the desired temperature range. In particular, it is crucial to use reliable temperature coefficients of the stiffness, piezoelectric, dielectric, and expansion constants of the propagation medium to achieve correct simulations of the considered devices. Currently, the best-suited piezoelectric material for high-temperature SAW applications is langasite (LGS). Unfortunately, the available coefficients do not allow for precise prediction of the temperature dependence of LGS-based SAW devices above 300°C. A novel method, based on a simulated annealing algorithm coupled with a Rayleigh wave simulation program, was developed to find optimal LGS temperature coefficients. This approach has proven to yield accurate results up to at least 800°C. PMID:24081262

  3. Comparison of the sensitive property between soman and its simulant DMMP by hydrogen-bond acidic polymer coated SAW sensor

    NASA Astrophysics Data System (ADS)

    Wang, Yang; Du, Xiaosong; Long, Yin; Jiang, Yadong

    2014-08-01

    Hydrogen-bond acidic (HBA) polymers are widely used for the detection of dimethyl methyl phosphonate (DMMP, a simulant of real nerve agents) based on surface acoustic wave (SAW) sensors. This paper presented an HBA polymer PLF, and subsequently the polymer was dissolved into chloroform and spray-coated on a SAW device to fabricate a gas sensor. Then the sensor was equipped into a SAW test platform to investigate its sensitive property to soman vapor and its simulant DMMP at the concentrations below 20 mg/m3. Results revealed that the sensor showed high sensitivity to the analyte vapors, furthermore, the response of the sensor to soman vapor was relatively smaller and slower than that to DMMP. Tests to some common interference vapors were studied at the concentration of 10 mg/m3, and the results indicated that the sensor showed a good selective property.

  4. Effect of applied force and blade speed on histopathology of bone during resection by sagittal saw.

    PubMed

    James, Thomas P; Chang, Gerard; Micucci, Steven; Sagar, Amrit; Smith, Eric L; Cassidy, Charles

    2014-03-01

    A sagittal saw is commonly used for resection of bone during joint replacement surgery. During sawing, heat is generated that can lead to an increase in temperature at the resected surface. The aim of this study was to determine the effect of applied thrust force and blade speed on generating heat. The effect of these factors and their interactions on cutting temperature and bone health were investigated with a full factorial Design of Experiments approach for two levels of thrust force, 15 N and 30 N, and for two levels of blade oscillation rate, 12,000 and 18,000 cycles per minute (cpm). In addition, a preliminary study was conducted to eliminate blade wear as a confounding factor. A custom sawing fixture was used to crosscut samples of fresh bovine cortical bone while temperature in the bone was measured by thermocouple (n=40), followed by measurements of the depth of thermal necrosis by histopathological analysis (n=200). An analysis of variance was used to determine the significance of the factor effects on necrotic depth as evidenced by empty lacunae. Both thrust force and blade speed demonstrated a statistically significant effect on the depth of osteonecrosis (p<0.05), while the interaction of thrust force with blade speed was not significant (p=0.22). The minimum necrotic depth observed was 0.50mm, corresponding to a higher level of force and blade speed (30 N, 18,000 cpm). Under these conditions, a maximum temperature of 93°C was measured at 0.3mm from the kerf. With a decrease in both thrust force and blade speed (15N, 12,000 cpm), the temperature in the bone increased to 109°C, corresponding to a nearly 50% increase in depth of the necrotic zone to 0.74 mm. A predictive equation for necrotic depth in terms of thrust force and blade speed was determined through regression analysis and validated by experiment. The histology results imply that an increase in applied thrust force is more effective in reducing the depth of thermal damage to surrounding bone than an increase in blade speed. PMID:24405736

  5. Measurements of Streams Agitated by Fluid Loaded SAW-devices Using a Volumetric 3-component Measurement Technique (V3V)

    NASA Astrophysics Data System (ADS)

    Kiebert, Florian; König, Jörg; Kykal, Carsten; Schmidt, Hagen

    Utilizing surface acoustic waves (SAW) to induce tailored fluid motion via the acoustic streaming requires detailed knowledge about the acoustic bulk wave excitation. For the first time, the Defocus Digital Particle Image Velocimetry is used to measure the fluid motion originating from a fluid loaded SAW-device. With this flow measurement technique, the acoustic streaming-induced fluid motion can be observed volumetrically, which is attractive not only for application, but also for simulation in order to gain deeper insights regarding three-dimensional acoustic effects.

  6. [Dispersion of the nematodes belonging to the Bursaphelenchus xylophilus species group with saw timber in Russian Federation].

    PubMed

    Akhmatovich, N A; Ryss, A Iu

    2009-01-01

    Four new records of Bursaphelenchus mucronatus in saw-timbers from the Asian part of Russia (Irkutsk Oblast and Krasnoyarsk Krai, larch, pine and spruce wood) intercepted in St. Petersburg, are described, measured and illustrated. The diagnosis of B. mucronatus is amended and its relationships within species group xylophilus, and especially its differences from a quarantine pests B. xylophilus, are given. The record of the B. mucronatus transition from Asiatic into European part of Russia suggests possible transcontinental way of the xylophilus group penetration with saw-timber. Pest risk analysis of B. xylophilus for the European part of Russia is discussed in scope of the global warming. PMID:20198962

  7. Constraint on the heavy sterile neutrino mixing angles in the SO(10) model with double see-saw mechanism

    E-print Network

    Takeshi Fukuyama; Tatsuru Kikuchi; Koichi Matsuda

    2008-04-22

    Constraints on the heavy sterile neutrino mixing angles are studied in the framework of a minimal supersymmetric ${\\rm SO}(10)$ model with {\\it double see-saw mechanism}. A new singlet matter in addition to the right-handed neutrinos is introduced to realize the double see-saw mechanism. The minimal ${\\rm SO}(10)$ model gives an unambiguous Dirac neutrino mass matrix, which enables us to predict the masses and the mixing angles in the enlarged $9 \\times 9$ neutrino mass matrix. Mixing angles between the light Majorana neutrinos and the heavy sterile neutrinos are shown to be within the LEP experimental bound on all ranges of the Majorana phases.

  8. Light composite scalar boson from a see-saw mechanism in two-scale TC models

    NASA Astrophysics Data System (ADS)

    Doff, A.; Natale, A. A.

    2015-09-01

    We consider the possibility of a light composite scalar boson arising from mass mixing between a relatively light and heavy scalar singlets in a see-saw mechanism expected to occur in two-scale Technicolor (TC) models. A light composite scalar boson can be generated when the TC theory features two technifermions species in different representations, R1 and R2, under a single technicolor gauge group, with characteristic scales ?1 and ?2. We determine the final composite scalar fields, ?1 and ?2, effective theory using the effective potential for composite operators approach. To generate a light composite scalar it is enough to have a walking (or quasi-conformal) behavior just for one of the technifermions representations.

  9. Light composite scalar boson from a see-saw mechanism in two-scale TC models

    E-print Network

    A. Doff; A. A. Natale

    2015-06-25

    We consider the possibility of a light composite scalar boson arising from mass mixing between a relatively light and heavy scalar singlets in a see-saw mechanism expected to occur in two-scale Technicolor (TC) models. A light composite scalar boson can be generated when the TC theory features two technifermions species in different representations, $R_1$ and $R_2$, under a single technicolor gauge group, with characteristic scales $\\Lambda_1$ and $\\Lambda_2$. We determine the final composite scalar fields, $\\Phi_1$ and $\\Phi_2$, effective theory using the effective potential for composite operators approach. To generate a light composite scalar it is enough to have a walking (or quasi-conformal) behavior just for one of the technifermions representations.

  10. Light composite scalar boson from a see-saw mechanism in two-scale TC models

    E-print Network

    Doff, A

    2015-01-01

    We consider the possibility of a light composite scalar boson arising from mass mixing between a relatively light and heavy scalar singlets in a see-saw mechanism expected to occur in two-scale Technicolor (TC) models. A light composite scalar boson can be generated when the TC theory features two technifermions species in different representations, $R_1$ and $R_2$, under a single technicolor gauge group, with characteristic scales $\\Lambda_1$ and $\\Lambda_2$. We determine the final composite scalar fields, $\\Phi_1$ and $\\Phi_2$, effective theory using the effective potential for composite operators approach. To generate a light composite scalar it is enough to have a walking (or quasi-conformal) behavior just for one of the technifermions representations.

  11. Behavior of platinum/tantalum as interdigital transducers for SAW devices in high-temperature environments.

    PubMed

    Aubert, Thierry; Elmazria, Omar; Assouar, Badreddine; Bouvot, Laurent; Hehn, Michel; Weber, Sylvain; Oudich, Mourad; Genève, Damien

    2011-03-01

    In this paper, we report on the use of tantalum as adhesion layer for platinum electrodes used in high-temperature SAW devices based on langasite substrates (LGS). Tantalum exhibits a great adhesive strength and a very low mobility through the Pt film, ensuring a device lifetime at 900°C of about one hour in an air atmosphere and at least 20 h under vacuum. The latter is limited by morphological modifications of platinum, starting with the apparition of crystallites on the surface, followed by important terracing and breaking of the film continuity. Secondary neutral mass spectroscopy (SNMS), Auger electron spectroscopy (AES), X-ray diffraction (XRD) measurements, and comparison with iridium-based electrodes allowed us to show that this deterioration is likely intrinsic to platinum film, consisting of agglomeration phenomena. Finally, based on these results, we present a solution that could significantly enhance the lifetime of Pt-based IDTs placed in high-temperature conditions. PMID:21429851

  12. Los Alamos National Laboratory corregated metal pipe saw facility preliminary safety analysis report. Volume I

    SciTech Connect

    1990-09-19

    This Preliminary Safety Analysis Report addresses site assessment, facility design and construction, and design operation of the processing systems in the Corrugated Metal Pipe Saw Facility with respect to normal and abnormal conditions. Potential hazards are identified, credible accidents relative to the operation of the facility and the process systems are analyzed, and the consequences of postulated accidents are presented. The risk associated with normal operations, abnormal operations, and natural phenomena are analyzed. The accident analysis presented shows that the impact of the facility will be acceptable for all foreseeable normal and abnormal conditions of operation. Specifically, under normal conditions the facility will have impacts within the limits posted by applicable DOE guidelines, and in accident conditions the facility will similarly meet or exceed the requirements of all applicable standards. 16 figs., 6 tabs.

  13. SAW RFID-Tags for Mass-Sensitive Detection of Humidity and Vapors.

    PubMed

    Lieberzeit, Peter A; Palfinger, Christian; Dickert, Franz L; Fischerauer, Gerhard

    2009-01-01

    One-port surface acoustic wave (SAW) devices with defined reflector patterns give characteristic signal patterns in the time domain making them identifiable and leading to so-called RFID-Tags. Each sensor responds with a burst of signals, their timed positions giving the identification code, while the amplitudes can be related to the analyte concentration. This paper presents the first combination of such a transducer with chemically sensitive layer materials. These include crosslinked polyvinyl alcohol for determining relative humidity and tert-butylcalix[4]arene for detecting solvent vapors coated on the free space between the reflectors. In going from the time domain to the frequency domain by Fourier transformation, changes in frequency and phase lead to sensor responses. Hence, it is possible to measure the concentration of tetrachloroethene in air down to 50 ppm, as well as 1% changes in relative humidity. PMID:22303149

  14. Evaluation of Residual Stresses Using Laser-Generated SAWs on Surface of Laser-Welding Plates

    NASA Astrophysics Data System (ADS)

    Dong, Li-ming; Li, Jia; Ni, Chen-yin; Shen, Zhong-hua; Ni, Xiao-wu

    2013-06-01

    In this paper, residual stresses in laser-welding plates are studied by both numerical simulation and experiment based on laser ultrasonics. First, a three-dimensional finite-element model is developed to predict temperature distributions and thermo-structure response during the laser-welding process of an aluminum alloy plate, and the residual stresses around the joint are described from structure analysis. After that, experiments based on surface acoustic waves generated by a pulsed laser are carried out to determine the velocity distribution of SAWs around the joint, from which the distribution of main residual stresses are calculated according to acoustoelastic theory. By comparing the thermal-structure model results with the measurements, it is found that the numerical simulation results are in good agreement with the experimental data.

  15. Ultra low-power hybrid spintronics-straintronics clocked with Surface Acoustic Waves (SAW)

    NASA Astrophysics Data System (ADS)

    Salehi Fashami, Mohammad; Bandyopadhyay, Supriyo; Atulasimha, Jayasimha

    2014-03-01

    The study of magnetization dynamics in magnetostrictive materials triggered with surface acoustic waves (SAWs) is of great interest not only from a fundamental point of view, but also for potential applications in energy efficient nanomagnetic computing. In this presentation, we model magnetization dynamics in dipole coupled arrays of nanomagnets clocked by acoustic waves. Specifically, this theoretical work demonstrates the feasibility of sequential logic devices such as flip-flops by showing that NAND gates and information propagation with cross-over of nanomagnet ``wires'' can be implemented and synchronously clocked with surface acoustic waves. We acknowledge support of the National Science Foundation (NSF) under NSF CAREER grant CCF-1253370, the NEB2020 Grant ECCS-1124714 and SHF grant CCF-1216614 as well as the Semiconductor Research Company (SRC) under NRI task 2203.001.

  16. Strict Authentication Watermarking with JPEG Compression (SAW-JPEG) for Medical Images

    E-print Network

    Zain, Jasni Mohamad

    2011-01-01

    This paper proposes a strict authentication watermarking for medical images. In this scheme, we define region of interest (ROI) by taking the smallest rectangle around an image. The watermark is generated from hashing the area of interest. The embedding region is considered to be outside the region of interest as to preserve the area from distortion as a result from watermarking. The strict authentication watermarking is robust to some degree of JPEG compression (SAW-JPEG). JPEG compression will be reviewed. To embed a watermark in the spatial domain, we have to make sure that the embedded watermark will survive JPEG quantization process. The watermarking scheme, including data embedding, extracting and verifying procedure were presented. Experimental results showed that such a scheme could embed and extract the watermark at a high compression rate. The watermark is robust to a high compression rate up to 90.6%. The JPEG image quality threshold is 60 for the least significant bit embedding. The image quality ...

  17. A simple phenomenological model of tunable SAW devices using magnetostrictive thin films.

    PubMed

    Robbins, W P; Hietala, A

    1988-01-01

    A simple phenomenological model has been developed that is useful for the approximate design of tunable SAW (surface acoustic wave) devices using magnetostrictive thin films. The model formulation, based on perturbation theory, relates the maximum magnetic-field-dependent velocity change or tunability range to the frequency of operation, film thickness, elastic properties of the film and substrate, and magnetic properties of the film. Iron-terbium-boron films deposited on quartz and lithium niobate substrates were used to verify the formula. A significant variability in the magnetic properties of the films was obtained by varying the amount of terbium (0-5 at.%) in the film (80% Fe and 15-20% B). A simple figure of merit for comparing various film-substrate combinations, independent of device dimensions, was derived and experimentally checked. PMID:18290208

  18. Shape-Selectivity with Liquid Crystal and Side-Chain Liquid Crystalline Polymer SAW Sensor Interfaces

    SciTech Connect

    FRYE-MASON,GREGORY CHARLES; OBORNY,MICHAEL C.; PUGH,COLEEN; RICCO,ANTONIO; THOMAS,ROSS C.; ZELLERS,EDWARD T.; ZHANG,GUO-ZHENG

    1999-09-23

    A liquid crystal (LC) and a side-chain liquid crystalline polymer (SCLCP) were tested as surface acoustic wave (SAW) vapor sensor coatings for discriminating between pairs of isomeric organic vapors. Both exhibit room temperature smectic mesophases. Temperature, electric-field, and pretreatment with self-assembled monolayers comprising either a methyl-terminated or carboxylic acid-terminated alkane thiol anchored to a gold layer in the delay path of the sensor were explored as means of affecting the alignment and selectivity of the LC and SCLCP films. Results for the LC were mixed, while those for the SCLCP showed a consistent preference for the more rod-like isomer of each isomer pair examined.

  19. Transverse waveguide mode suppression for Pt-electrode SAW resonators on quartz and LGS.

    PubMed

    Meulendyk, Bennett J; Pereira da Cunha, Mauricio

    2011-12-01

    SAW resonators on ST-X quartz and langasite (LGS) [0°, 144°, 24°] are currently being used for hydrogen fluoride (HF) vapor sensing and high-temperature sensing, respectively. For these applications, the use of Pt-based electrodes allows the resonators to withstand the targeted harsh environments. This work reveals that for Pt-electrode resonators with conventional short-circuit gratings on the aforementioned quartz and LGS orientations, acoustic energy leaks from the grating region to the bus bars, thus degrading the resonator response. To resolve this problem, this paper proposes and implements open-circuit gratings for resonators fabricated with these substrate/metal combinations. The open-circuit gratings guide the acoustic energy within the grating region, resulting in greater quality factors and reduced losses in the resonator response. In addition, scalar potential theory is utilized in this work to identify transverse waveguide modes in the responses of open-circuit grating resonators on quartz and LGS. A transverse waveguide mode dispersion relation was derived to extend the scalar potential theory to account for asymmetry in the slowness curve around the propagation direction. This is the case for several commonly used LGS orientations, in particular LGS [0°, 144°, 24°]. Finally, this work addresses spurious transverse mode mitigation by scaling both the transducer's grating aperture and electrode overlap width. Open circuit grating resonators with appropriately scaled transducer designs were fabricated and tested, resulting in a 71% increase in quality factor and a spurious mode rejection of over 26 dBc for Pt-electrode devices on ST-X quartz. This progress directly translates into better frequency resolution and increased dynamic range for HF vapor sensors and high-temperature SAW devices. PMID:23443708

  20. New Mass Properties Engineers Aerospace Ballasting Challenge Facilitated by the SAWE Community

    NASA Technical Reports Server (NTRS)

    Cutright, Amanda; Shaughnessy, Brendan

    2010-01-01

    The discipline of Mass Properties Engineering tends to find the engineers; not typically vice versa. In this case, two engineers quickly found their new responsibilities deep in many aspects of mass properties engineering and required to meet technical challenges in a fast paced environment. As part of NASA's Constellation Program, a series of flight tests will be conducted to evaluate components of the new spacecraft launch vehicles. One of these tests is the Pad Abort 1 (PA-1) flight test which will test the Launch Abort System (LAS), a system designed to provide escape for astronauts in the event of an emergency. The Flight Test Articles (FTA) used in this flight test are required to match mass properties corresponding to the operational vehicle, which has a continually evolving design. Additionally, since the structure and subsystems for the Orion Crew Module (CM) FTA are simplified versions of the final product, thousands of pounds of ballast are necessary to achieve the desired mass properties. These new mass properties engineers are responsible for many mass properties aspects in support of the flight test, including meeting the ballasting challenge for the CM Boilerplate FTA. SAWE expert and experienced mass properties engineers, both those that are directly on the team and many that supported via a variety of Society venues, significantly contributed to facilitating the success of addressing this particular mass properties ballasting challenge, in addition to many other challenges along the way. This paper discusses the details regarding the technical aspects of this particular mass properties challenge, as well as identifies recommendations for new mass properties engineers that were learned from the SAWE community along the way.

  1. 76 FR 62678 - Table Saw Blade Contact Injuries; Advance Notice of Proposed Rulemaking; Request for Comments and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-11

    ... accidental contact with the blade. In the Federal Register of July 9, 2003 (68 FR 40912) and September 5, 2003 (68 FR 52753), we invited comments on the issues raised by the petition (Petition No. CP03-2). We... COMMISSION 16 CFR Chapter II Table Saw Blade Contact Injuries; Advance Notice of Proposed Rulemaking;...

  2. Acoustoelectric Effect on the Responses of SAW Sensors Coated with Electrospun ZnO Nanostructured Thin Film

    PubMed Central

    Tasaltin, Cihat; Ebeoglu, Mehmet Ali; Ozturk, Zafer Ziya

    2012-01-01

    In this study, zinc oxide (ZnO) was a very good candidate for improving the sensitivity of gas sensor technology. The preparation of an electrospun ZnO nanostructured thin film on a 433 MHz Rayleigh wave based Surface Acoustic Wave (SAW) sensor and the investigation of the acoustoelectric effect on the responses of the SAW sensor are reported. We prepared an electrospun ZnO nanostructured thin film on the SAW devices by using an electrospray technique. To investigate the dependency of the sensor response on the structure and the number of the ZnO nanoparticles, SAW sensors were prepared with different coating loads. The coating frequency shifts were adjusted to fall between 100 kHz and 2.4 MHz. The sensor measurements were performed against VOCs such as acetone, trichloroethylene, chloroform, ethanol, n-propanol and methanol vapor. The sensor responses of n-propanol have opposite characteristics to the other VOCs, and we attributed these characteristics to the elastic effect/acoustoelectric effect.

  3. The last century saw an explosion in activity in every avenue of materials science. As the understanding

    E-print Network

    Rubloff, Gary W.

    The last century saw an explosion in activity in every avenue of materials science materials chips' by Xiang and Schultz6, and the field of combinatorial materials science still appearsDepartment of Materials Science and Engineering and Center for Superconductivity Research, University

  4. AlN films deposited by dc magnetron sputtering and high power impulse magnetron sputtering for SAW applications

    NASA Astrophysics Data System (ADS)

    Ait Aissa, K.; Achour, A.; Elmazria, O.; Simon, Q.; Elhosni, M.; Boulet, P.; Robert, S.; Djouadi, M. A.

    2015-04-01

    In this work, aluminium nitride (AlN) films were deposited on silicon substrates buffered by an epitaxial AlN thin film for surface acoustic wave (SAW) applications. The films were deposited by dc magnetron sputtering (dcMS) and high power impulse magnetron sputtering (HiPIMS) deposition techniques. The structural properties of AlN films were investigated using x-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy and atomic force microscopy. In both cases of films deposited by dcMS and HiPIMS, the XRD results showed that the obtained films are oriented, with full width at half maximum rocking curves of around 1°. Raman spectroscopy revealed higher residual stress relaxation in the AlN epilayers grown by HiPIMS compared to AlN grown by dcMS, highlighted by a blue shift in the E2(high) Raman mode. The SAW measurements indicated an insertion loss of AlN-SAW devices of about 53 and 35?dB for the AlN films deposited by dcMS and HiPIMS respectively. The relation between the structural properties of AlN and the characteristics of AlN-SAW devices were correlated and discussed.

  5. KU releases 2014 crime statistics LAWRENCE --Crime at the University of Kansas saw a 24 percent increase in 2014,

    E-print Network

    KU releases 2014 crime statistics LAWRENCE -- Crime at the University of Kansas saw a 24 percent increase in 2014, KU's Public Safety Office announced today with the release of its annual crime statistics Ralph Oliver, director of Public Safety. Violent crime -- defined by the FBI as murder, rape, robbery

  6. On the Old Saw That Dialogue Is a Socratic but Not an Aristotelian Method of Moral Education

    ERIC Educational Resources Information Center

    Kristjánsson, Kristján

    2014-01-01

    Kristján Kristjánsson's aim in this article is to bury the old saw that dialogue is exclusively a Socratic but not an Aristotelian method of education for moral character. Although the truncated discussion in Aristotle's "Nicomachean Ethics" of the character development of the young may indicate that it is merely the result of…

  7. Surface Acoustic Waves (SAW)-Based Biosensing for Quantification of Cell Growth in 2D and 3D Cultures.

    PubMed

    Wang, Tao; Green, Ryan; Nair, Rajesh Ramakrishnan; Howell, Mark; Mohapatra, Subhra; Guldiken, Rasim; Mohapatra, Shyam Sundar

    2015-01-01

    Detection and quantification of cell viability and growth in two-dimensional (2D) and three-dimensional (3D) cell cultures commonly involve harvesting of cells and therefore requires a parallel set-up of several replicates for time-lapse or dose-response studies. Thus, developing a non-invasive and touch-free detection of cell growth in longitudinal studies of 3D tumor spheroid cultures or of stem cell regeneration remains a major unmet need. Since surface acoustic waves (SAWs) permit mass loading-based biosensing and have been touted due to their many advantages including low cost, small size and ease of assembly, we examined the potential of SAW-biosensing to detect and quantify cell growth. Herein, we demonstrate that a shear horizontal-surface acoustic waves (SH-SAW) device comprising two pairs of resonators consisting of interdigital transducers and reflecting fingers can be used to quantify mass loading by the cells in suspension as well as within a 3D cell culture platform. A 3D COMSOL model was built to simulate the mass loading response of increasing concentrations of cells in suspension in the polydimethylsiloxane (PDMS) well in order to predict the characteristics and optimize the design of the SH-SAW biosensor. The simulated relative frequency shift from the two oscillatory circuit systems (one of which functions as control) were found to be concordant to experimental data generated with RAW264.7 macrophage and A549 cancer cells. In addition, results showed that SAW measurements per se did not affect viability of cells. Further, SH-SAW biosensing was applied to A549 cells cultured on a 3D electrospun nanofiber scaffold that generate tumor spheroids (tumoroids) and the results showed the device's ability to detect changes in tumor spheroid growth over the course of eight days. Taken together, these results demonstrate the use of SH-SAW device for detection and quantification of cell growth changes over time in 2D suspension cultures and in 3D cell culture models, which may have potential applications in both longitudinal 3D cell cultures in cancer biology and in regenerative medicine. PMID:26703604

  8. A phytochemical comparison of saw palmetto products using gas chromatography and 1H nuclear magnetic resonance spectroscopy metabolomic profiling

    PubMed Central

    Booker, Anthony; Suter, Andy; Krnjic, Ana; Strassel, Brigitte; Zloh, Mire; Said, Mazlina; Heinrich, Michael

    2014-01-01

    Objectives Preparations containing saw palmetto berries are used in the treatment of benign prostatic hyperplasia (BPH). There are many products on the market, and relatively little is known about their chemical variability and specifically the composition and quality of different saw palmetto products notwithstanding that in 2000, an international consultation paper from the major urological associations from the five continents on treatments for BPH demanded further research on this topic. Here, we compare two analytical approaches and characterise 57 different saw palmetto products. Methods An established method – gas chromatography – was used for the quantification of nine fatty acids, while a novel approach of metabolomic profiling using 1H nuclear magnetic resonance (NMR) spectroscopy was used as a fingerprinting tool to assess the overall composition of the extracts. Key findings The phytochemical analysis determining the fatty acids showed a high level of heterogeneity of the different products in the total amount and of nine single fatty acids. A robust and reproducible 1H NMR spectroscopy method was established, and the results showed that it was possible to statistically differentiate between saw palmetto products that had been extracted under different conditions but not between products that used a similar extraction method. Principal component analysis was able to determine those products that had significantly different metabolites. Conclusions The metabolomic approach developed offers novel opportunities for quality control along the value chain of saw palmetto and needs to be followed further, as with this method, the complexity of a herbal extract can be better assessed than with the analysis of a single group of constituents. PMID:24417505

  9. Predicting the Relationship Between System Vibration with Rock Brittleness Indexes in Rock Sawing Process

    NASA Astrophysics Data System (ADS)

    Mikaeil, Reza; Ataei, Mohammad; Ghadernejad, Saleh; Sadegheslam, Golsa

    2014-03-01

    The system vibration is a very significant measure of the sawing performance, because it indicates the amount of energy required to saw the rock. The maintenance cost of system is also dependant on system vibration. A few increases in system vibration cause a huge increase in the maintenance cost of the system. In this paper, the vibration of system in terms of RMSa was investigated and models for estimation of vibration by means of rock brittleness indexes and operational specifications were designed via statistical models and multiple curvilinear regression analysis. In this study, the relationships between rock brittleness indexes and operational specifications were investigated by regression analysis in statistical package for social science (SPSS) and the results of determination coefficients have been presented. In the second part, the diagrams show that a point lying on the line indicates an exact estimation. In the plot for model, the points are scattered uniformly about the diagonal line, suggesting that the models are good. It is very useful to evaluate the vibration of system and select the suitable operational characteristics by only some mechanical properties of rock. Drgania uk?adu uwa?ane s? za miernik wydajno?ci procesu urabiania, poniewa? pokazuj? ilo?? energii niezb?dnej do urabiania ska?y. Od poziomu drga? zale?? tak?e koszty eksploatacji systemu. Nieznaczny nawet wzrost poziomu drga? prowadzi do znacznego zwi?kszenia kosztów eksploatacyjnych urz?dzenia. W pracy tej przeprowadzono analiz? drga? (ich warto?ci skutecznych) i opracowano model estymacji poziomu drga? w oparciu o wspó?czynnik krucho?ci ska? i parametry eksploatacyjne urz?dzenia. W pracy wykorzystano modele statystyczne i wielokrotn? analiz? metod? regresji krzywoliniowej. W pracy obecnej zwi?zek pomi?dzy wspó?czynnikiem krucho?ci ska? a parametrami eksploatacyjnymi urz?dzenia badano z wykorzystaniem analizy metod? regresji dost?pnej w statystycznym pakiecie oprogramowania dla nauk spo?ecznych (SPSS) a wyniki podano w postaci wyznaczonych wspó?czynników. W drugiej cz??ci pracy przedstawiono wykres pokazuj?cy, ze punkt le??cy na linii oznacza dok?adne oszacowanie. W wykresie wykonanym dla modelu punkty rozrzucone s? równomiernie wokó? linii przek?tnej, co sugeruje ?e modele s? w?a?ciwe. Okre?lenie poziomu drga? urz?dzenia jest niezwykle korzystnym zabiegiem pozwalaj?cym na dobór parametrów pracy urz?dzenia jedynie w oparciu o mechaniczne w?a?ciwo?ci ska?.

  10. TALSPEAK CURVE: AN ILLUSTRATION OF A SEE-SAW EFFECT IN SEPARATIONS

    SciTech Connect

    Peter Zalupski; Leigh Martin

    2010-11-01

    A superbly balanced thermodynamic struggle for metal ion coordination by aqueous aminopolycarboxylate reagent, DTPA, and non-aqueous organophosphorous phase transfer reagent, HDEHP, affords the separation of trivalent actinides from trivalent lanthanides under the umbrella of the Talspeak liquid-liquid distribution process. This thermodynamic relationship has been linked to an analogous “see-saw” behavior, where the balance is distorted when either of the key complexing players is subject to adverse conditions that interfere with their optimal operation. The thermodynamic balance is tipped in favour of HDEHP whenever increased acidity of the aqueous solution out-competes the metal ion complexation by aqueous complexing agent. Also enhanced steric crowding may switch-off efficient coordination of the metal ion. When HDEHP is depolymerised due to the presence of aliphatic alcohol in the organic phase its phase transferring power is diminished. Such complication paves way for DTPA to establish its dominance on the distribution of trivalent metal ions in the 2-phase system. The illustrated sensitivity of the thermodynamic balance between DTPA and HDEHP in Talspeak-type systems may serve as informative tool when studying less-predictable realms of Talspeak chemistry.

  11. Comparison of dust release from epoxy and paint nanocomposites and conventional products during sanding and sawing.

    PubMed

    Gomez, Virginia; Levin, Marcus; Saber, Anne T; Irusta, Silvia; Dal Maso, Miikka; Hanoi, Roberto; Santamaria, Jesus; Jensen, Keld A; Wallin, Håkan; Koponen, Ismo K

    2014-10-01

    The release of dust generated during sanding or sawing of nanocomposites was compared with conventional products without nanomaterials. Epoxy-based polymers with and without carbon nanotubes, and paints with different amounts of nano-sized titanium dioxide, were machined in a closed aerosol chamber. The temporal evolution of the aerosol concentration and size distribution were measured simultaneously. The morphology of collected dust by scanning electron microscopy was different depending on the type of nanocomposites: particles from carbon nanotubes (CNTs) nanocomposites had protrusions on their surfaces and aggregates and agglomerates are attached to the paint matrix in particles emitted from alkyd paints. We observed no significant differences in the particle size distributions when comparing sanding dust from nanofiller containing products with dust from conventional products. Neither did we observe release of free nanomaterials. Instead, the nanomaterials were enclosed or partly enclosed in the matrix. A source strength term Si (cm(-3) s(-1)) that describes particle emission rates from continuous sources was introduced. Comparison between the Si parameters derived from sanding different materials allows identification of potential effects of addition of engineered nanoparticles to a composite. PMID:25030708

  12. Phenomenological Consequences of See-Saw in S4 Based Models

    E-print Network

    F. Bazzocchi; L. Merlo; S. Morisi

    2009-08-07

    It was proposed a flavour model based on the symmetry group S4, managing to describe fermion masses and mixings. The Weinberg operator has been used in order to provide the smallness of the neutrino masses, while a set of scalar fields, getting non-vanishing vacuum expectation values, spontaneously breaks down S4 and provides the Tri-Bimaximal pattern as the lepton mixing matrix. Restricting to this setting, in this paper we analyze possible origins for the effective terms: the type I See-Saw mechanism is the best known approach, but also the type II and III are discussed. The phenomenology related to these models is various and the next future experiments could in principle discriminate among these proposals. Furthermore, we compare our realizations to two relevant A4 based models, also predicting the Tri-Bimaximal lepton mixing, and we find that an analysis on the neutrinoless double beta decay parameters could distinguish among all these realizations. Furthermore a combined measurement of the effective mass and of the lightest neutrino mass could indicate in the next future which is the preferred flavour symmetry group. The introduction of new physics beyond the Standard Model, like heavy right-handed neutrinos, scalar triplets and fermion triplets, let us investigate on leptogenesis and this provides constraints in the realization of the models.

  13. Chemical quality of the Saw Mill River, Westchester County, New York, 1981-83

    USGS Publications Warehouse

    Rogers, R.J.

    1984-01-01

    Surface waters, bottom sediments and coatings formed on artificial substrates (ceramic tiles) were analyzed to evaluate the chemical quality of the Saw Mill River, New York. Heavy metals, nutrients, and organic contaminants were studied. Dissolved orthophosphate concentrations were highest in the lower third of the river. Dissolved manganese was the only metal to exceed U.S. Environmental Protection Agency water-quality criteria. Arsenic, cadmium, copper, lead, and zinc concentrations were highest in waters from the lowest 4 river miles. Concentrations of copper, lead, and zinc in bottom sediments from the lowest 3 river miles were greater than in upstream sediments. Concentrations of nine heavy metals were higher on tiles emplaced below river mile 3 than on tiles upstream. Few organic compounds were detected in the water column; none persisted at all sites. Chlordane, DDD, DDE, DDT, dieldrin, and polychlorinated biphenyls (PCB's) were found in bottom sediments throughout the basin. PCB concentrations were highest in the lowest 6 river miles; the other organic compounds exhibited no spatial patterns. Polynuclear aromatic hydrocarbons were most abundant in bottom sediments from the lowest 2 river miles. Collectively the distribution of contaminants indicates that river quality deteriorates in the lower, more heavily urbanized reach. (USGS)

  14. Continuous in vivo blood pressure measurements using a fully implantable wireless SAW sensor.

    PubMed

    Murphy, Olive H; Bahmanyar, Mohammad Reza; Borghi, Alessandro; McLeod, Christopher N; Navaratnarajah, Manoraj; Yacoub, Magdi H; Toumazou, Christofer

    2013-10-01

    In this paper, the development of a fully implantable wireless sensor able to provide continuous real-time accurate pressure measurements is presented. Surface Acoustic Wave (SAW) technology was used to deposit resonators on crystalline quartz wafers; the wafers were then assembled to produce a pressure sensitive device. Excitation and reading via a miniature antenna attached to the pressure sensor enables continuous external interrogation. The main advantages of such a configuration are the long term stability of quartz and the low power necessary for the interrogation, which allows 24/7 interrogation by means of a hand-held, battery powered device. Such data are of vital importance to clinicians monitoring and treating the effects of hypertension and heart failure. A prototype was designed and tested using both a bio-phantom test rig and an animal model. The pressure traces for both compare very well with a commercially available catheter tip pressure transducer. The work presented in this paper is the first known wireless pressure data from the left ventricle of the heart of a living swine. PMID:23559403

  15. Low Energy Signatures of the TeV Scale See-Saw Mechanism

    E-print Network

    A. Ibarra; E. Molinaro; S. T. Petcov

    2011-06-21

    We study a type I see-saw scenario where the right-handed (RH) neutrinos, responsible for the light neutrino mass generation, lie at the electroweak scale. Under certain conditions, the strength of the charged and neutral current weak interactions of the Standard Model particles with the heavy RH neutrinos can be large enough to allow their production at the LHC, opening also the possibility of observing other low energy signatures of the new physics in the electroweak precision observables as well as in searches for rare leptonic decays or neutrinoless double beta decay. We argue that in this scenario the flavour structure of the neutrino Yukawa couplings is essentially determined by the low energy neutrino parameters, leading to fairly strong correlations among the new phenomena. In particular, we show that the present bound on the $\\mu \\to e +\\gamma$ decay rate makes very difficult the observation of the heavy RH neutrinos at the LHC or the observation of deviations from the Standard Model predictions in the electroweak precision data. We also argue that all present experimental constraints on this scenario still allow i) for an enhancement of the rate of neutrinoless double beta decay, which thus can be in the range of sensitivity of the GERDA experiment even when the light Majorana neutrinos possess a normal hierarchical mass spectrum, and ii) for the predicted $\\mu \\to e+ \\gamma$ decay rate to be within the sensitivity range of the MEG experiment.

  16. The numerical analysis of general SAW and leaky wave devices using approximate Green's function representations.

    PubMed

    Peach, Robert C

    2009-10-01

    The Green's function or boundary element method (BEM) is the best available technique for rigorous surface acoustic wave (SAW) device analysis. However, its computational cost usually means that it cannot be applied directly to devices with complex, nonperiodic electrode structures. In this paper, approximate forms for the Green's function are employed. They are based on rigorous representations, they can represent the Green's function to any required degree of accuracy, and they can be applied to any type of substrate and acoustic wave. The use of this type of approximation for practical device analysis is considered, and computational procedures are presented that can exploit the special approximate Green's function structure. It is shown that highly efficient computational algorithms can be constructed, in which the computational effort increases linearly with the number of electrodes in the device. These methods can be applied to any type of device structure, and they do not require any empirically derived parameters. The practical application of the methods is illustrated by examples of longitudinally coupled resonator filter (LCRF) designs implemented using leaky wave cuts of lithium tantalate. Agreement between theory and experiment is excellent, even for devices of this complexity. PMID:19942514

  17. Characterizing components of the Saw Palmetto Berry Extract (SPBE) on prostate cancer cell growth and traction

    SciTech Connect

    Scholtysek, Carina; Krukiewicz, Aleksandra A.; Alonso, Jose-Luis; Goldmann, Wolfgang H.

    2009-02-13

    Saw Palmetto Berry Extract (SPBE) is applied for prostate health and treatment of urinary tract infections, nonbacterial prostitis and Benign Prostatic Hyperplasia (BPH) in man. An assumption is that SPBE affects tumor cell progression and migration in breast and prostate tissue. In this work, DU-145 cells were used to demonstrate that SPBE and its sterol components, {beta}-sitosterol and stigmasterol, inhibit prostate cancer growth by increasing p53 protein expression and also inhibit carcinoma development by decreasing p21 and p27 protein expression. In the presence of cholesterol, these features are not only reversed but increased significantly. The results show for the first time the potential of SPBE, {beta}-sitosterol and stigmasterol as potential anti-tumor agents. Since the protein p53 is also regarded as nuclear matrix protein facilitating actin cytoskeletal binding, 2D tractions were measured. The cell adhesion strength in the presence of SPBE, {beta}-sitosterol and cholesterol and the observation was that the increase in p53 expression triggered an increase in the intracellular force generation. The results suggest a dual function of p53 in cells.

  18. Saw-tooth refractive lens for high energy x-ray focusing

    NASA Astrophysics Data System (ADS)

    Antimonov, Mikhail A.; Khounsary, Ali M.

    2014-09-01

    Saw-tooth refractive lens (SRL) provides a comparatively attractive option for X-ray focusing. An SRL assembly consists of two parts, each with an array of triangular structures (prisms), set tilted symmetrically with respect to the incoming beam. Its main advantage is a simple, continuous tunability in energy and focal length. SRLs can be used for both long and short focal length focusing. Long focal distance focusing of an SRL can accurately be predicted using simple analytical relations. However, the focus size at short focal distances focusing may deviate appreciably from the expected demagnified source size when: (1) the length of the SRL is comparable with the focusing distance, (2) the incident beam is not monochromatic, and (3) and the distance between adjacent prism tips, the tip step, is large . The first factor was considered in a previous work while the other two are addressed is this paper. This preliminary work is aimed at a better understanding of the SRL lenses for focusing an undulator beamline at the Advanced Photon Source (APS).

  19. Expression of the bipolar see-saw in Antarctic climate records during the last deglaciation

    NASA Astrophysics Data System (ADS)

    Stenni, B.; Buiron, D.; Frezzotti, M.; Albani, S.; Barbante, C.; Bard, E.; Barnola, J. M.; Baroni, M.; Baumgartner, M.; Bonazza, M.; Capron, E.; Castellano, E.; Chappellaz, J.; Delmonte, B.; Falourd, S.; Genoni, L.; Iacumin, P.; Jouzel, J.; Kipfstuhl, S.; Landais, A.; Lemieux-Dudon, B.; Maggi, V.; Masson-Delmotte, V.; Mazzola, C.; Minster, B.; Montagnat, M.; Mulvaney, R.; Narcisi, B.; Oerter, H.; Parrenin, F.; Petit, J. R.; Ritz, C.; Scarchilli, C.; Schilt, A.; Schüpbach, S.; Schwander, J.; Selmo, E.; Severi, M.; Stocker, T. F.; Udisti, R.

    2011-01-01

    Ice-core records of climate from Greenland and Antarctica show asynchronous temperature variations on millennial timescales during the last glacial period. The warming during the transition from glacial to interglacial conditions was markedly different between the hemispheres, a pattern attributed to the thermal bipolar see-saw. However, a record from the Ross Sea sector of East Antarctica has been suggested to be synchronous with Northern Hemisphere climate change. Here we present a temperature record from the Talos Dome ice core, also located in the Ross Sea sector. We compare our record with ice-core analyses from Greenland, based on methane synchronization, and find clearly asynchronous temperature changes during the deglaciation. We also find distinct differences in Antarctic records, pointing to differences in the climate evolution of the Indo-Pacific and Atlantic sectors of Antarctica. In the Atlantic sector, we find that the rate of warming slowed between 16,000 and 14,500years ago, parallel with the deceleration of the rise in atmospheric carbon dioxide concentrations and with a slight cooling over Greenland. In addition, our chronology supports the hypothesis that the cooling of the Antarctic Cold Reversal is synchronous with the Bølling-Allerød warming in the northern hemisphere 14,700years ago.

  20. 2F2 IGEC TRANSACTIONS ON UI;I'RASONICS, FERROELECTRICS, AND FREQUENCY CONI'ItOI,, VOI,. 48, NO. 1, JANTJARY 2001 Dual SAW Sensor Technique for Determining

    E-print Network

    Brinker, C. Jeffrey

    changes [a], [6],pressure and temperature changes [7],and stress changcs [8],[9].SAW sensors have also, JANTJARY 2001 Dual SAW Sensor Technique for Determining Mass and Modulus Changes Susan L. Hietala, Member (SAW) sensors, which are sensitive to a variety of surface changes, have been widely used for chemical

  1. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - PORTER-CABLE CIRCULAR SAW OENHP: 2001-04, VERSION A

    SciTech Connect

    Unknown

    2002-01-15

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated glove boxes at the Department of Energy's (DOE) Los Alamos facility. The Porter-Cable circular saw was assessed on August 15-16, 2001 (Porter-Cable No.1 and Porter-Cable No.2, respectively). During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Porter-Cable saw is a straightforward machine for cutting wood of varying thickness. The blade is fully guarded with a fixed upper and a lower retractable guard. The lower guard retracts as the blade engages the work piece. The unit is operated with an on/off guarded trigger switch and is supported with a handgrip mounted near the front of the saw. The saw is equipped with a directional nozzle, which aims sawdust away from the operator and the line of cut. An optional vacuum system, attached to the directional nozzle, is used to remove and collect dust. During the demonstration of Porter-Cable No.1, personal noise sampling indicated that one worker was under and one was at the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) with time-weighted averages (TWA's) of 82.7 and 84.6 dBA, respectively. During the demonstration of Porter-Cable No.2, however, both workers did exceed the Action Level with TWA's of 89.7 and 90.0 dBA. These data are not entirely representative as they were gathered during a simulation and not at the actual worksite. Additional sampling should be conducted on-site, but the workers should wear hearing protection until it is determined that it is no longer necessary. The total nuisance dust sample for Porter-Cable No.1 was 3.53 milligrams per cubic meter (mg/m{sup 3}), which is lower than the OSHA Permissible Exposure Limit (PEL) of 15 mg/m{sup 3} and the American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold Limit Value (TLV) of 10 mg/m{sup 3}. Porter-Cable No.2's nuisance dust results yielded a value of 22.05 mg/m{sup 3}, which is over the PEL and TLV. The fiber analysis for the first demonstration yielded 12.9 fibers per cubic centimeter (f/cc), which is much higher than the PEL of 1 f/cc. Galson Laboratories considered the fiber analysis for the second demonstration void due to the overloading of dust on the filter. Kickback, the sudden reaction to a pinched blade, is possible with this saw and could cause the saw to lift up and out of the work piece and toward the operator. Proper work position and firm control of the saw minimizes the potential for a sprain or strain. Care needs to be exercised to support the work piece properly and to not force the tool.

  2. Dual SAW sensor technique for determining mass and modulus changes in thin silicate films during gas adsorption

    SciTech Connect

    Hietala, S.L.; Hietala, V.M.; Brinker, C.J.

    2000-01-10

    Surface acoustic wave (SAW) sensors, which are sensitive to a variety of surface changes, have been widely used for chemical and physical sensing. The ability to control or compensate for the many surface forces has been instrumental in collecting valid data. In cases where it is not possible to neglect certain effects, such as frequency drift with temperature, methods such as the dual sensor technique have been utilized. This paper describes a novel use of a dual sensor technique, using two sensor materials, Quartz and GaAs, to separate out the contributions of mass and modulus of the frequency change during gas adsorption experiments. The large modulus change in the film calculated using this technique, and predicted by the Gassmann equation, provide a greater understanding of the challenges of SAW sensing.

  3. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - EVOLUTION 180 CIRCULAR SAW OENHP: 2001-03, VERSION A

    SciTech Connect

    Unknown

    2002-01-25

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated gloveboxes at the Department of Energy's (DOE) Los Alamos facility. The Evolution 180 circular saw was assessed on August 14, 2001. During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Evolution 180 is a portable, metal cutting circular saw with a 7-inch diameter blade. The blade is contained within the main housing and has a retractable lower blade guard to prevent operator access to the blade during operation and shutdown. The saw is equipped with a chip collector. The maximum cutting thickness for metal is one-quarter inch and can cut steel tubing and pipe 2 inches in diameter. The unit is operated with an on/off guarded trigger switch and is supported with the hand guide mounted to the side of the saw. An adjustable lever sets the depth of the cut. The machine's circuitry will automatically shut the saw motor off if excessive overload is detected during operation. The one-half hour demonstration involved vertical and horizontal cuts and blade changes. During this process, operators experienced binding of the saw. This caused the blade to become hot, causing the sawdust collected in the chip collector to smoke. Care should be exercised to use the appropriate blade for the application, operator training, and personal protective equipment (PPE). Personal noise sampling indicated that neither worker was over the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) with time-weighted averages (TWA's) of 69.1 and 68.8 dBA. The personal noise sample taken during the special demonstration with the stainless steel plate had a TWA of 69.8 dBA. These data are not entirely representative as they were gathered during a simulation and not at the actual worksite. Additional sampling should be conducted on-site, but the workers should wear hearing protection until it is determined that it is no longer necessary. The total nuisance dust sample for the Evolution 180 circular saw was 3.5 milligrams per cubic meter (mg/m{sup 3}), which is lower than the OSHA Permissible Exposure Limit (PEL) of 15 mg/m{sup 3} and the American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold Limit Value (TLV) of 10 mg/m{sup 3}. The fiber analysis yielded 1.74 fibers per cubic centimeter (f/cc), which is above the PEL of 1 f/cc. Although the nuisance dust levels were low, fiberglass dust levels were higher than the PEL. Since fiberglass dust is known to be a strong skin irritant and a possible human carcinogen, the workers should continue to wear appropriate suits and gloves, as well as a full-face air-purifying respirator. The respirator should be equipped with a combination organic vapor and acid gas cartridge in combination with a High Particulate Air (HEPA) filter, since particulate filter, since during the demonstration, the workers complained of an odd smell, which may have been from the breakdown of the fiberglass.

  4. Control of surface mobility for conformal deposition of Mo-Si multilayers on saw-tooth substrates

    NASA Astrophysics Data System (ADS)

    Voronov, D. L.; Anderson, E. H.; Gullikson, E. M.; Salmassi, F.; Warwick, T.; Yashchuk, V. V.; Padmore, H. A.

    2013-11-01

    Multilayer-coated blazed gratings (MBG) are the most promising solution for ultra-high resolution soft X-ray spectroscopy, since they can have very high groove density and provide high-order operation and very high diffraction efficiency. The performance of MBGs however depends critically on the conformal deposition of the multilayer (ML) stack on a saw-tooth substrate and the minimization of roughness. We present an analysis of the roughening and smoothing processes during growth of Mo/Si multilayers deposited over a range of pressures of Ar sputtering gas on flat and saw-tooth substrates. A Linear Continuum Model (LCM) of the film growth was used to understand the interplay between smoothing and roughening of the ML films and to predict the optimum conditions for deposition. The MBG coated under the optimal deposition conditions demonstrated high diffraction efficiency in the EUV and soft X-ray wavelength ranges

  5. Survey of blood parasites in two forest owls, Northern Saw-whet Owls and Flammulated Owls, of western North America.

    PubMed

    Leppert, Lynda L; Dufty, Alfred M; Stock, Sarah; Oleyar, M David; Kaltenecker, Greg S

    2008-04-01

    Except for a few studies in the eastern United States, little has been published on hemoparasites in owls. We surveyed the blood parasites of 108 Northern Saw-whet Owls (Aegolius acadicus) and 24 Flammulated Owls (Otus flammeolus) in Idaho during autumn migration in 1999 and 2000. We also surveyed 15 Flammulated Owls (FLOW) during breeding season in Utah from 2000. Leucocytozoon ziemanni, Haemoproteus syrnii, Haemoproteus noctuae, and Trypanosoma avium were identified. The overall prevalence of infection was 53% (78/147) and for the combined species, prevalences of Haemoproteus, Leucocytozoon, and Trypanosoma species were 20%, 39%, and 4%, respectively. Northern Saw-whet Owls (NSWO) had an overall prevalence of 51% (55/108), with prevalences of 6%, 47%, and 4% by hemoparasite genus, respectively. Flammulated Owls had an overall prevalence of 59% (23/39), with prevalences of 56%, 18%, and 5% by genus, respectively. This study provides baseline hematozoa information for two boreal owl species. PMID:18436683

  6. Performance Prediction of Large-Diameter Circular Saws Based on Surface Hardness Tests for Mugla (Turkey) Marbles

    NASA Astrophysics Data System (ADS)

    Güney, Avni

    2011-05-01

    Surface hardness tests such as Shore hardness (SH) and Schmidt hammer rebound hardness (SR) may provide a quick and inexpensive measure of rock hardness, which may be widely used for estimating the mechanical properties of rock material such as strength, sawability, drillability and cuttability. In the marble industry, circular sawing with diamond sawblades constitutes a major cost in the processing. Therefore, several models based on the relations between hourly slab production ( P hs), rock surface hardness (SH and SR) and mineral grain size ( S cr) were developed using the data obtained from field and laboratory measurements on five different marbles quarried in the Mugla Province of Turkey. The models which include surface hardness and crystal size may as well be used for the prediction of sawability (hourly slab production) of carbonate rocks using large-diameter circular saws.

  7. Effects of pumpkin seed oil and saw palmetto oil in Korean men with symptomatic benign prostatic hyperplasia.

    PubMed

    Hong, Heeok; Kim, Chun-Soo; Maeng, Sungho

    2009-01-01

    This study was to investigate the role of complementary and alternative medicine in the prevention and treatment of benign prostatic hyperplasia. For this purpose, a randomized, double-blind, placebo-controlled trial was performed over 12 months on 47 benign prostatic hyperplasia patients with average age of 53.3 years and international prostate symptom score over 8. Subjects received either sweet potato starch (group A, placebo, 320 mg/day), pumpkin seed oil (group B, 320 mg/day), saw palmetto oil (group C, 320 mg/day) or pumpkin seed oil plus saw palmetto oil (group D, each 320 mg/day). International prostate symptom score, quality of life, serum prostate specific antigen, prostate volume and maximal urinary flow rate were measured. In groups B, C and D, the international prostate symptom score were reduced by 3 months. Quality of life score was improved after 6 months in group D, while those of groups B and C were improved after 3 months, compared to the baseline value. Serum prostate specific antigen was reduced only in group D after 3 months, but no difference was observed in prostate volume in all treatment groups. Maximal urinary flow rate were gradually improved in groups B and C, with statistical significance after 6 months in group B and after 12 months in group C. None of the parameters were significantly improved by combined treatment with pumpkin seed oil and saw palmetto oil. From these results, it is suggested that administrations of pumpkin seed oil and saw palmetto oil are clinically safe and may be effective as complementary and alternative medicine treatments for benign prostatic hyperplasia. PMID:20098586

  8. Material property evaluations of bimetallic welds, stainless steel saw fusion lines, and materials affected by dynamic strain aging

    SciTech Connect

    Rudland, D.; Scott, P.; Marschall, C.; Wilkowski, G.

    1997-04-01

    Pipe fracture analyses can often reasonably predict the behavior of flawed piping. However, there are material applications with uncertainties in fracture behavior. This paper summarizes work on three such cases. First, the fracture behavior of bimetallic welds are discussed. The purpose of the study was to determine if current fracture analyses can predict the response of pipe with flaws in bimetallic welds. The weld joined sections of A516 Grade 70 carbon steel to F316 stainless steel. The crack was along the carbon steel base metal to Inconel 182 weld metal fusion line. Material properties from tensile and C(T) specimens were used to predict large pipe response. The major conclusion from the work is that fracture behavior of the weld could be evaluated with reasonable accuracy using properties of the carbon steel pipe and conventional J-estimation analyses. However, results may not be generally true for all bimetallic welds. Second, the toughness of austenitic steel submerged-arc weld (SAW) fusion lines is discussed. During large-scale pipe tests with flaws in the center of the SAW, the crack tended to grow into the fusion line. The fracture toughness of the base metal, the SAW, and the fusion line were determined and compared. The major conclusion reached is that although the fusion line had a higher initiation toughness than the weld metal, the fusion-line J-R curve reached a steady-state value while the SAW J-R curve increased. Last, carbon steel fracture experiments containing circumferential flaws with periods of unstable crack jumps during steady ductile tearing are discussed. These instabilities are believed to be due to dynamic strain aging (DSA). The paper discusses DSA, a screening criteria developed to predict DSA, and the ability of the current J-based methodologies to assess the effect of these crack instabilities. The effect of loading rate on the strength and toughness of several different carbon steel pipes at LWR temperatures is also discussed.

  9. Safe fronto-orbito-zygomatic osteotomy using a diamond-coated threadwire saw in orbito-zygomatic craniotomy

    PubMed Central

    Wada, Kojiro; Mori, Kentaro; Toyooka, Terushige; Otani, Naoki; Fujii, Kazuya; Ueno, Hideaki; Tomura, Satoshi; Tomiyama, Arata

    2015-01-01

    Orbito-zygomatic craniotomy is a widely accepted skull-based technique, but osteotomy at the malar eminence (ME) is complicated. We have developed a safe fronto-orbito-zygomatic (FOZ) osteotomy by creating small guide burr holes in the superior and lateral parts of the orbital wall and cutting the bone using a diamond-coated threadwire saw. This method involves standard two-piece osteotomy by creating small superior and lateral guide orbital burr holes instead of sectioning into the superior and inferior orbital fissures. The guide burr holes are connected using a diamond-coated threadwire saw to create the FOZ bar. This method was applied to the treatment of four patients with skull-based tumors or internal carotid and basilar artery aneurysms. Postoperative three-dimensional bone density computed tomography showed minimum bone gap in the ME. No craniotomy-related complication has occurred. FOZ osteotomy by creating guide burr holes in the orbital wall and cutting the bone using a diamond-coated threadwire saw is safe and results in minimum bone gap in the ME. PMID:26396621

  10. Modelling based on Spatial Impulse Response Model for Optimization of Inter Digital Transducers (SAW Sensors) for Non Destructive Testing

    NASA Astrophysics Data System (ADS)

    Fall, D.; Duquennoy, M.; Ouaftouh, M.; Piwakowski, B.; Jenot, F.

    This study deals with modelling SAW-IDT transducers for their optimization. These sensors are specifically developed to characterize properties of thin layers, coatings and functional surfaces. Among the methods of characterization, the ultrasonic methods using Rayleigh surface waves are particularly interesting because the propagation of these waves is close to the surface of material and the energy is concentrated within a layer under the surface of about one wavelength thick. In order to characterize these coatings and structures, it is necessary to work in high frequencies, this is why in this study, SAW-IDT sensors are realized for surface acoustic wave generation. For optimization of these SAW-IDT sensors, particularly their band-width, it is necessary to study various IDT configurations by varying the number of electrodes, dimensions of the electrodes, their shapes and spacings. Thus it is necessary to implement effective and rapid technique for modelling. The originality of this study is to develop simulation tools based on Spatial Impulse Response model. Therefore it will be possible to reduce considerably computing time and results are obtained in a few seconds, instead of several hours (or days) by using finite element method. In order to validate this method, theoretical and experimental results are compared with finite element method and Interferometric measurements. The results obtained show a good overall concordance and confirm effectiveness of suggested method.

  11. Detection, Identification, Location, and Remote Sensing using SAW RFID Sensor Tags

    NASA Technical Reports Server (NTRS)

    Barton, Richard J.

    2009-01-01

    In this presentation, we will consider the problem of simultaneous detection, identification, location estimation, and remote sensing for multiple objects. In particular, we will describe the design and testing of a wireless system capable of simultaneously detecting the presence of multiple objects, identifying each object, and acquiring both a low-resolution estimate of location and a high-resolution estimate of temperature for each object based on wireless interrogation of passive surface acoustic wave (SAW) radiofrequency identification (RFID) sensor tags affixed to each object. The system is being studied for application on the lunar surface as well as for terrestrial remote sensing applications such as pre-launch monitoring and testing of spacecraft on the launch pad and monitoring of test facilities. The system utilizes a digitally beam-formed planar receiving antenna array to extend range and provide direction-of-arrival information coupled with an approximate maximum-likelihood signal processing algorithm to provide near-optimal estimation of both range and temperature. The system is capable of forming a large number of beams within the field of view and resolving the information from several tags within each beam. The combination of both spatial and waveform discrimination provides the capability to track and monitor telemetry from a large number of objects appearing simultaneously within the field of view of the receiving array. In the presentation, we will summarize the system design and illustrate several aspects of the operational characteristics and signal structure. We will examine the theoretical performance characteristics of the system and compare the theoretical results with results obtained from experiments in both controlled laboratory environments and in the field.

  12. See-saw rocking: an in vitro model for mechanotransduction research.

    PubMed

    Tucker, R P; Henningsson, P; Franklin, S L; Chen, D; Ventikos, Y; Bomphrey, R J; Thompson, M S

    2014-08-01

    In vitro mechanotransduction studies, uncovering the basic science of the response of cells to mechanical forces, are essential for progress in tissue engineering and its clinical application. Many varying investigations have described a multitude of cell responses; however, as the precise nature and magnitude of the stresses applied are infrequently reported and rarely validated, the experiments are often not comparable, limiting research progress. This paper provides physical and biological validation of a widely available fluid stimulation device, a see-saw rocker, as an in vitro model for cyclic fluid shear stress mechanotransduction. This allows linkage between precisely characterized stimuli and cell monolayer response in a convenient six-well plate format. Models of one well were discretized and analysed extensively using computational fluid dynamics to generate convergent, stable and consistent predictions of the cyclic fluid velocity vectors at a rocking frequency of 0.5 Hz, accounting for the free surface. Validation was provided by comparison with flow velocities measured experimentally using particle image velocimetry. Qualitative flow behaviour was matched and quantitative analysis showed agreement at representative locations and time points. Maximum shear stress of 0.22 Pa was estimated near the well edge, and time-average shear stress ranged between 0.029 and 0.068 Pa. Human tenocytes stimulated using the system showed significant increases in collagen and GAG secretion at 2 and 7 day time points. This in vitro model for mechanotransduction provides a versatile, flexible and inexpensive method for the fluid shear stress impact on biological cells to be studied. PMID:24898022

  13. See-saw rocking: an in vitro model for mechanotransduction research

    PubMed Central

    Tucker, R. P.; Henningsson, P.; Franklin, S. L.; Chen, D.; Ventikos, Y.; Bomphrey, R. J.; Thompson, M. S.

    2014-01-01

    In vitro mechanotransduction studies, uncovering the basic science of the response of cells to mechanical forces, are essential for progress in tissue engineering and its clinical application. Many varying investigations have described a multitude of cell responses; however, as the precise nature and magnitude of the stresses applied are infrequently reported and rarely validated, the experiments are often not comparable, limiting research progress. This paper provides physical and biological validation of a widely available fluid stimulation device, a see-saw rocker, as an in vitro model for cyclic fluid shear stress mechanotransduction. This allows linkage between precisely characterized stimuli and cell monolayer response in a convenient six-well plate format. Models of one well were discretized and analysed extensively using computational fluid dynamics to generate convergent, stable and consistent predictions of the cyclic fluid velocity vectors at a rocking frequency of 0.5 Hz, accounting for the free surface. Validation was provided by comparison with flow velocities measured experimentally using particle image velocimetry. Qualitative flow behaviour was matched and quantitative analysis showed agreement at representative locations and time points. Maximum shear stress of 0.22 Pa was estimated near the well edge, and time-average shear stress ranged between 0.029 and 0.068 Pa. Human tenocytes stimulated using the system showed significant increases in collagen and GAG secretion at 2 and 7 day time points. This in vitro model for mechanotransduction provides a versatile, flexible and inexpensive method for the fluid shear stress impact on biological cells to be studied. PMID:24898022

  14. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - DEWALT RECIPROCATING SAW OENHP{number_sign}: 2001-01, VERSION A

    SciTech Connect

    Unknown

    2002-01-31

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated glove boxes at the Department of Energy's (DOE) Los Alamos facility. The DeWalt reciprocating saw was assessed on August 13, 2001. During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The DeWalt reciprocating saw is a hand-held industrial tool used for cutting numerous materials, including wood and various types of metals depending upon the chosen blade. Its design allows for cutting close to floors, corners, and other difficult areas. An adjustable shoe sets the cut at three separate depths. During the demonstration for the dismantling of the fiberglass-reinforced plywood crate, the saw was used for extended continuous cutting, over a period of approximately two hours. The dismantling operation involved vertical and horizontal cuts, saw blade changes, and material handling. During this process, operators experienced vibration to the hand and arm in addition to a temperature rise on the handgrip. The blade of the saw is partially exposed during handling and fully exposed during blade changes. Administrative controls, such as duty time of the operators and the machine, operator training, and personal protective equipment (PPE), such as gloves, should be considered when using the saw in this application. Personal noise sampling indicated that both workers were exposed to noise levels exceeding the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) with time-weighted averages (TWA's) of 88.3 and 90.6 dBA. Normally, a worker would be placed in a hearing conservation program if his TWA was greater than the Action Level. In this case, however, monitoring was conducted during a simulation, not during the actual work conducted at the worksite. Additional sampling should be conducted at the worksite to determine the actual noise levels for the workers. Until it is determined that the actual TWA's are less than the Action Level, the workers should use PPE. A training program on the proper use and wearing of the selected PPE should be provided to each worker. Nuisance dust monitoring yielded a concentration of 10.69 milligrams per cubic meter (mg/m{sup 3}). Although this is less than the OSHA Permissible Exposure Limit (PEL) of 15 mg/m{sup 3}, it is above the American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold Limit Value (TLV) of 10 mg/m{sup 3}. Fiberglass dust monitoring yielded a fiber count of 1.7 fibers per cubic centimeter (f/cc). This is above the PEL and the TLV of 1.0 f/cc. Therefore, controls should be implemented (engineering or PPE) to reduce the workers' exposure to the dust. Respirators should be used if engineering controls do not sufficiently control the dust or fiberglass generated. Respirators should be equipped with an organic vapor and acid gas cartridge with a High Efficiency Particulate Air (HEPA) filter, since during the demonstration, the workers complained of an odd smell, which may have been from the breakdown of the fiberglass.

  15. A SAW-Based Chemical Sensor for Detecting Sulfur-Containing Organophosphorus Compounds Using a Two-Step Self-Assembly and Molecular Imprinting Technology

    PubMed Central

    Pan, Yong; Yang, Liu; Mu, Ning; Shao, Shengyu; Wang, Wen; Xie, Xiao; He, Shitang

    2014-01-01

    This paper presents a new effective approach for the sensitive film deposition of surface acoustic wave (SAW) chemical sensors for detecting organophosphorus compounds such as O-ethyl-S-2-diisopropylaminoethyl methylphosphonothiolate (VX) containing sulfur at extremely low concentrations. To improve the adsorptive efficiency, a two-step technology is proposed for the sensitive film preparation on the SAW delay line utilizing gold electrodes. First, mono[6-deoxy-6-[(mercaptodecamethylene)thio

  16. Deep Sub-micro mol{\\cdot }{mol}^{-1} Water-Vapor Measurement by Dual-Ball SAW Sensors for Temperature Compensation

    NASA Astrophysics Data System (ADS)

    Takeda, N.; Oizumi, T.; Tsuji, T.; Akao, S.; Takayanagi, K.; Nakaso, N.; Yamanaka, K.

    2015-08-01

    A collimated surface acoustic wave (SAW) circles around the equator of a sphere hundreds of times. Because of the long distance travel of the collimated SAW, a small change in the SAW propagation caused by the environment of the sphere can be accumulated as a measurable range in amplitude and/or in delay time. So, a spherical SAW device enables highly sensitive water-vapor measurements. In this paper, deep sub \\upmu mol{\\cdot }mol^{-1} water-vapor detection by 1 mm diameter quartz crystal ball SAW sensors is described. To measure such a low water-vapor concentration in real time, it is necessary to compensate the temperature dependence of the ball SAW sensor, which is about 20 ppm{\\cdot }° C^{-1} in delay time change. A dual-frequency burst analog detector was developed for the temperature compensation in real time. By using a harmonic SAW sensor, which was excited by 80 MHz and 240 MHz at the same time, it was confirmed that the delay time drift for a temperature range of 21.0°C ± 1.0°C became less than 0.05 ppm in delay time change. By using dual-ball SAW sensors (which included a 150 MHz sensor with a water-vapor sensitive layer and a 240 MHz sensor as a reference), water-vapor concentrations from 0.1 \\upmu mol{\\cdot }mol^{-1} to 5 \\upmu mol{\\cdot }mol^{-1} were successfully measured. It appears that the delay time change is proportional to the square root of the water-vapor concentration. The detection limit determined by the electrical noise of the system was estimated at 0.01 \\upmu mol{\\cdot }mol^{-1}.

  17. A SAW-based chemical sensor for detecting sulfur-containing organophosphorus compounds using a two-step self-assembly and molecular imprinting technology.

    PubMed

    Pan, Yong; Yang, Liu; Mu, Ning; Shao, Shengyu; Wang, Wen; Xie, Xiao; He, Shitang

    2014-01-01

    This paper presents a new effective approach for the sensitive film deposition of surface acoustic wave (SAW) chemical sensors for detecting organophosphorus compounds such as O-ethyl-S-2-diisopropylaminoethyl methylphosphonothiolate (VX) containing sulfur at extremely low concentrations. To improve the adsorptive efficiency, a two-step technology is proposed for the sensitive film preparation on the SAW delay line utilizing gold electrodes. First, mono[6-deoxy-6-[(mercaptodecamethylene)thio

  18. Dynamics of vegetation and soils of oak/saw palmetto scrub after fire: Observations from permanent transects

    NASA Technical Reports Server (NTRS)

    Schmalzer, Paul A.; Hinkle, G. Ross

    1991-01-01

    Ten permanent 15 m transects previously established in two oak/saw palmetto scrub stands burned in December 1986, while two transects remained unburned. Vegetation in the greater than 0.5 m and the less than 0.5 m layers on these transects was sampled at 6, 12, 18, 24, and 36 months postburn and determined structural features of the vegetation (height, percent bare ground, total cover). The vegetation data were analyzed from each sampling by height layer using detrended correspondence analysis ordination. Vegetation data for the greater than 0.5 m layer for the entire time sequence were combined and analyzed using detrended correspondence analysis ordination. Soils were sampled at 6, 12, 18, and 24 months postburn and analyzed for pH, conductivity, organic matter, exchangeable cations (Ca, Mg, K, Na), NO3-N, NH4-N, Al, available metals (Cu, Fe, Mn, Zn), and PO4-P. Shrub species recovered at different rates postfire with saw palmetto reestablishing cover greater than 0.5 m within one year, but the scrub oaks had not returned to preburn cover greater than 0.5 m in 3 years after the fire. These differences in growth rates resulted in dominance shifts after the fire with saw palmetto increasing relative to the scrub oaks. Overall changes in species richness were minor, although changes occurred in species richness by height layers due to different growth rates. Soils of well drained and poorly drained sites differed markedly. Soil responses to the fire appeared minor. Soil pH increased at 6 and 12 months postfire; calcium increased at 6 months postburn. Nitrate-nitrogen increased at 12 months postburn. Low values of conductivity, PO4-P, Mg, K, Na, and Fe at 12 months postburn may be related to heavy rainfall the preceding month. Seasonal variability in some soil parameters appeared to occur.

  19. Local heat transfer distribution in a square channel with 90 continuous, 90 saw tooth profiled and 60 broken ribs

    SciTech Connect

    Gupta, Abhishek; SriHarsha, V.; Prabhu, S.V.; Vedula, R.P.

    2008-02-15

    Internal channel cooling is employed in advanced gas turbines blade to allow high inlet temperatures so as to achieve high thrust/weight ratios and low specific fuel consumption. The objective of the present study is to measure the local heat transfer distributions in a double wall ribbed square channel with 90 continuous, 90 saw tooth profiled and 60 V-broken ribs. Comparison is made between the 90 continuous ribs (P/e = 7 and 10 for a e/D = 0.15) and 90 saw tooth profiled rib configurations (P/e = 7 for an e/D = 0.15) for the same rib height to the hydraulic diameter ratio (e/D). The effect of pitch to rib height ratio (P/e = 7.5,10 and 12) of 60 V-broken ribbed channel with a constant rib height to hydraulic diameter ratio (e/D) of 0.0625 on the local heat transfer distribution is studied. The Reynolds number based on duct hydraulic diameter is ranging from 10,000 to 30,000. A thin stainless steel foil of 0.05 mm thickness is used as heater and infrared thermography technique is used to obtain the local temperature distribution on the surface. The images are captured in the periodically fully developed region of the channel. It is observed that the heat transfer augmentations in the channel with 90 saw tooth profiled ribs are comparable with those of 90 continuous ribs. The enhancements caused by 60 V-broken ribs are higher than those of 90 continuous ribs. The effect of pitch to the rib height ratio (P/e) is not significant for channel with 60 V-broken ribs for a given rib height to hydraulic diameter ratio (e/D = 0.0625). (author)

  20. Effect of particle bombardment on the orientation and the residual stress of sputtered AlN films for SAW devices.

    PubMed

    Iborra, Enrique; Clement, Marta; Sangrador, Jesús; Sanz-Hervás, Alfredo; Vergara, Lucía; Aguilar, Miguel

    2004-03-01

    We present a study of the effect of particle bombardment on the preferred orientation and the residual stress of polycrystalline aluminum nitride (AlN) thin films for surface acoustic wave (SAW) applications. Films were deposited on silicon (100) substrates by radio frequency (RF) sputtering of an aluminum target in an argon and nitrogen gas mixture. The main deposition parameters were changed as follows: the total pressure from 4 mTorr to 11 mTorr, the N2 content in the gas mixture from 20% to 80%, and the substrate self-bias voltage from -10 V to -30 V. If a sufficiently high negative substrate self-bias voltage is induced, (00.2)-oriented films are obtained over the full ranges of pressure and N2 content. Such films have values of residual stress ranging from -3 GPa to +1 GPa, depending on the deposition conditions. Our results suggest that the energy of the Ar ions colliding with the substrate controls the preferred orientation of the films, whereas the directionality of the ions (for the same energy) is the main factor determining the residual stress. To demonstrate the suitability of our material for the intended application, SAW filters with good electroacoustic response have been fabricated using AlN thin films with optimized (00.2) orientation and controlled residual stress. PMID:15128222

  1. Constraints on the rare tau decays from mu --> e gamma in the supersymmetric see-saw model

    E-print Network

    Alejandro Ibarra; Cristoforo Simonetto

    2008-03-03

    It is now a firmly established fact that all family lepton numbers are violated in Nature. In this paper we discuss the implications of this observation for future searches for rare tau decays in the supersymmetric see-saw model. Using the two loop renormalization group evolution of the soft terms and the Yukawa couplings we show that there exists a lower bound on the rate of the rare process mu --> e gamma of the form BR(mu --> e gamma) > C BR(tau --> mu gamma) BR(tau --> e gamma), where C is a constant that depends on supersymmetric parameters. Our only assumption is the absence of cancellations among the high-energy see-saw parameters. We also discuss the implications of this bound for future searches for rare tau decays. In particular, for large regions of the mSUGRA parameter space, we show that present B-factories could discover either tau --> mu gamma or tau --> e gamma, but not both.

  2. Highly sensitive room-temperature surface acoustic wave (SAW) ammonia sensors based on Co?O?/SiO? composite films.

    PubMed

    Tang, Yong-Liang; Li, Zhi-Jie; Ma, Jin-Yi; Su, Hai-Qiao; Guo, Yuan-Jun; Wang, Lu; Du, Bo; Chen, Jia-Jun; Zhou, Weilie; Yu, Qing-Kai; Zu, Xiao-Tao

    2014-09-15

    Surface acoustic wave (SAW) sensors based on Co3O4/SiO2 composite sensing films for ammonia detection were investigated at room temperature. The Co3O4/SiO2 composite films were deposited onto ST-cut quartz SAW resonators by a sol-gel method. SEM and AFM characterizations showed that the films had porous structures. The existence of SiO2 was found to enhance the ammonia sensing property of the sensor significantly. The sensor based on a Co3O4/SiO2 composite film, with 50% Co3O4 loading, which had the highest RMS value (3.72), showed the best sensing property. It exhibited a positive frequency shift of 3500 Hz to 1 ppm ammonia as well as excellent selectivity, stability and reproducibility at room temperature. Moreover, a 37% decrease in the conductance of the composite film as well as a positive frequency shift of 12,500 Hz were observed when the sensor was exposed to 20 ppm ammonia, indicating the positive frequency shift was derived from the decrease in film conductance. PMID:25151235

  3. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - MILWAUKEE WORM DRIVE CIRCULAR SAW OENHP{number_sign}: 2001-02, VERSION A

    SciTech Connect

    Unknown

    2002-01-05

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated glove boxes at the Department of Energy's (DOE) Los Alamos facility. The Milwaukee worm drive circular saw was assessed on August 14, 2001. During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Milwaukee worm drive circular saw is a hand-held tool with a 7 1/4-inch diameter circular blade for cutting wood. The saw contains a fixed upper and a retractable lower blade guard to prevent access to the blade during use. The unit is operated with an on/off guarded trigger switch; and is supported with a handgrip mounted on top of the saw. An adjustable lever sets the depth of cut. The retractable blade guard permits blind or plunge cuts and protects from blade access during shutdown and blade coast. Kickback, the sudden reaction to a pinched blade, is possible when using this saw and could cause the saw to lift up and out of the work piece toward the operator. Proper work position and firm control of the saw minimizes the potential for a sprain or strain. Care needs to be exercised to support the work piece properly and to not force the tool. Personal noise sampling indicated that one worker was near the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) while the other was at the Action Level with time-weighted averages (TWA's) of 82.7 and 84.6 dBA, respectively. These data are not entirely representative as they were gathered during a simulation and not at the actual worksite. Additional sampling should be conducted on-site, but the workers should wear hearing protection until it is determined that it is no longer necessary. Air sampling was performed while the workers dismantled the fiberglass-reinforced crates. The total nuisance dust sample for the Milwaukee circular saw was 36.07 milligrams per cubic meter (mg/m{sup 3}), which is much higher than the OSHA Permissible Exposure Limit (PEL) of 15 mg/m{sup 3} and the American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold Limit Value (TLV) of 10 mg/m{sup 3}. Galson Laboratories considered the fiber analysis void due to the overloading of the filter. The PEL for fiberglass is 1 fiber per cubic centimeter (f/cc).

  4. Effect of saw dust on borate removal from groundwater in bench-scale simulation of permeable reactive barriers including magnesium oxide.

    PubMed

    Sasaki, K; Takamori, H; Moriyama, S; Yoshizaka, H; Hirajima, T

    2011-01-30

    Effective immobilization of boron in groundwater is a major challenge. Permeable reactive barrier (PRB) column tests for removal of borate have been investigated using MgO agglomerates as the primary reactive material over 40 weeks. Additionally, saw dust was also blended with MgO agglomerates to facilitate for borate removal in this system. Boron accumulation was more than 1.6 times greater in the presence of saw dust, although MgO alone performed well. Increased boron accumulation in the presence of saw dust was primarily due to higher porosity of the PRB column, decreasing the impact of secondary Mg(OH)(2) passivating layers and leaving more reactive sites on MgO agglomerates. In addition, Mg(2+) ions released from MgO agglomerates are complexed with carboxylic acids leached from saw dusts. This sequestration prevents the formation of bulky Mg(OH)(2) which is an ineffective sorbent for borate and covers the surfaces and passivating reactive sites on the MgO agglomerates. The morphologies of Mg(OH)(2) precipitated in the PRB column were also significantly affected by the presence of saw dust, with crystallization of needle-like particles of Mg(OH)(2) was prevented by Mg(2+) ions-organic ligand complexation. PMID:21075515

  5. Suppression of transverse mode responses in ultra-wideband SAW resonators fabricated on a Cu-grating/15 degrees YX-linbO3 structure.

    PubMed

    Omori, Tatsuya; Matsuda, Kenji; Yokoyama, Naofumi; Hashimoto, Ken-ya; Yamaguchi, Masatsune

    2007-10-01

    This paper discusses a technique to suppress spurious transverse mode responses appearing in ultra-wideband SAW resonators fabricated on a Cu-grating/15 degrees YX-LiNbO3 structure. The basic idea of the technique is inserting length- and width-weighted dummy electrodes between a bus-bar and interdigital electrodes. For practical device design, an analysis was made to show how the profile (field distribution) of both dominant and spurious transverse modes depends on the length and width (equivalent to SAW velocity) of the dummy electrodes. IDT-type SAW resonators were fabricated on a Cu-grating/15 degrees YX-LiNbO3 structure using the length- and width-weighted dummy electrodes. The experimental results were in good agreement with the theoretical analysis and prediction, showing that the proposed technique is effective in suppressing the spurious responses caused by the transverse modes. PMID:18019230

  6. Performance, kinetics, and equilibrium of methylene blue adsorption on biochar derived from eucalyptus saw dust modified with citric, tartaric, and acetic acids.

    PubMed

    Sun, Lei; Chen, Dongmei; Wan, Shungang; Yu, Zebin

    2015-12-01

    Biochar derived from eucalyptus saw dust modified with citric, tartaric, and acetic acids at low temperatures was utilized as adsorbent to remove methylene blue (MB) from aqueous solutions. Fourier transform infrared spectroscopy analysis showed that the carboxyl group was introduced on the biochar surface. Adsorption experiment data indicated that eucalyptus saw dust modified with citric acid showed higher MB adsorption efficiency than that modified with tartaric and acetic acids. Pseudo-second-order kinetics was the most suitable model for describing MB adsorption on biochar compared with pseudo-first-order, Elovich, and intraparticle diffusion models. The calculated values of ?G(0) and ?H(0) indicated the spontaneous and endothermic nature of the adsorption process. MB adsorption on biochar followed the Langmuir isotherm. The maximum adsorption capacities for eucalyptus saw dust modified with citric, tartaric, and acetic acids were 178.57, 99.01, and 29.94mgg(-1), respectively, at 35°C. PMID:26402873

  7. Development of Methods of Producing Large Areas of Silicon Sheet by the Slicing of Silicon Ingots Using Inside Diameter (I.D.) Saws

    NASA Technical Reports Server (NTRS)

    Aharonyan, P.

    1979-01-01

    Methods of producing large areas of silicon sheets were developed by using inside diameter (I.D.) saws to slice silicon ingots. A 16 inch automated I.D. slicing machine was modified to accept programmable electric feed system, a crystal rotating system and a dyna-track blade monitoring and control system. The saw and accessories were used to slice 75 mm diameter single crystal silicon ingots while rotating them. The automated saw automatically recovered the wafers and loaded them into a cassette. The amount of material lost during slicing was reduced by using smaller blades than ones normally used to slice the wafers. Slicing runs on 100 mm diameter silicon is the next goal.

  8. Enhancing chemical identification efficiency by SAW sensor transients through a data enrichment and information fusion strategy—a simulation study

    NASA Astrophysics Data System (ADS)

    Singh, Prashant; Yadava, R. D. S.

    2013-05-01

    The paper proposes a new approach for improving the odor recognition efficiency of a surface acoustic wave (SAW) transient sensor system based on a single polymer coating. The vapor identity information is hidden in transient response shapes through dependences on specific vapor solvation and diffusion parameters in the polymer coating. The variations in the vapor exposure and purge durations and the sensor operating frequency have been used to create diversity in transient shapes via termination of the vapor-polymer equilibration process up to different stages. The transient signals were analyzed by the discrete wavelet transform using Daubechies-4 mother wavelet basis. The wavelet approximation coefficients were then processed by principal component analysis for creating feature space. The set of principal components define the vapor identity information. In an attempt to enhance vapor class separability we analyze two types of information fusion methods. In one, the sensor operation frequency is fixed and the sensing and purge durations are varied, and in the second, the sensing and purge durations are fixed and the sensor operating frequency is varied. The fusion is achieved by concatenation of discrete wavelet coefficients corresponding to various transients prior to the principal component analysis. The simulation experiments with polyisobutylene SAW sensor coating for operation frequencies over [55-160] MHz and sensing durations over [5-60] s were analyzed. The target vapors are seven volatile organics: chloroform, chlorobenzene, o-dichlorobenzene, n-heptane, toluene, n-hexane and n-octane whose concentrations were varied over [10-100] ppm. The simulation data were generated using a SAW sensor transient response model that incorporates the viscoelastic effects due to polymer coating and an additive noise source in the output. The analysis reveals that: (i) in single transient analysis the class separability increases with sensing duration for a given frequency of operation, and also with frequency for a given sensing duration, and (ii) the information fusion based on both the multiple sensing cycles and the multiple sensing frequencies enhances the class separability by nearly an order of magnitude.

  9. Chemical class specificity using self-assembled monolayers on SAW devices: Effects of adsorption time and substrate grain size

    SciTech Connect

    Thomas, R.C.; Ricco, A.J.; DiRubio, C.R.; Yang, H.C.; Crooks, R.M.

    1997-07-01

    The authors report selectivity and sensitivity for 97-MHz SAW (surface acoustic wave) sensors functionalized with (COO{sup {minus}}){sub 2}/Cu{sup 2+}-terminated, organomercaptan-based, self-assembled monolayers (SAMs). Responses were obtained as a function of SAM formation time on thin Au films of controlled grain size. The authors find that the SAM films (1) preferentially adsorb classes of organic analytes according to simple chemical interaction concepts, (2) reversibly adsorb multilayers of some analytes well below their saturation vapor pressure, (3) adsorb more diisopropylmethylphosphonate (DIMP) at a given partial pressure as SAM solution-phase adsorption time increases, and (4) adsorb more DIMP at a given partial pressure as the grain size of the supporting Au film decreases.

  10. Inspection of processes during silicon wafer sawing using low coherence interferometry in the near infrared wavelength region

    NASA Astrophysics Data System (ADS)

    Gastinger, Kay; Johnsen, Lars; Simonsen, Ove; Aksnes, Astrid

    2011-05-01

    Multi-wire sawing of silicon wafers is a tribological process. Slurry consisting of small silicon carbide particles embedded in polyethyleneglycol carries out the abrasive material removal process. During this process small silicon chips are removed from the bulk material. Low coherence interferometry (LCI) is widely used for high accuracy surface topography measurements of materials. This paper presents an application of LCI where the surface of a material (silicon) is inspected from the inside. Light in the near infrared (NIR) wavelength region is used. High spatial resolution is necessary to be able to observe the processes on the micro scale. Therefore a modified solid immersion approach is suggested. That makes it possible to reach a spatial resolution in the range of the illumination wavelength. The topography changes produced by the chippings are in the range of some micrometers. To be able to estimate the volumes of the Si chippings interferometric phase measurements are applied.

  11. See-Saw Composite Higgses at the LHC: Linking Naturalness to the $750$ GeV Di-Photon Resonance

    E-print Network

    No, Jose Miguel; Setford, Jack

    2015-01-01

    We explore the possibility of explaining the recent $\\sim 750$ GeV excesses observed by ATLAS and CMS in the $\\gamma\\gamma$ spectrum in the context of a compelling theory of Naturalness. The potential spin-zero resonance responsible for the excesses also requires the existence of new heavy charged states. We show that both such features are naturally realized in a see-saw Composite Higgs model for EWSB, where the new pseudo-Goldstone bosons are expected to be comparatively heavier than the SM Higgs, and the new fermions have masses in the TeV range. If confirmed, the existence of this new resonance could be the first stone in the construction of a new theory of Naturalness.

  12. See-Saw Composite Higgses at the LHC: Linking Naturalness to the $750$ GeV Di-Photon Resonance

    E-print Network

    Jose Miguel No; Veronica Sanz; Jack Setford

    2015-12-17

    We explore the possibility of explaining the recent $\\sim 750$ GeV excesses observed by ATLAS and CMS in the $\\gamma\\gamma$ spectrum in the context of a compelling theory of Naturalness. The potential spin-zero resonance responsible for the excesses also requires the existence of new heavy charged states. We show that both such features are naturally realized in a see-saw Composite Higgs model for EWSB, where the new pseudo-Goldstone bosons are expected to be comparatively heavier than the SM Higgs, and the new fermions have masses in the TeV range. If confirmed, the existence of this new resonance could be the first stone in the construction of a new theory of Naturalness.

  13. Single-monolayer in situ modulus measurements using a SAW device: Photocrosslinking of a diacetylenic thiol-based monolayer

    SciTech Connect

    Ricco, A.J.; Staton, A.W.; Crooks, R.M.; Kim, Taisun

    1997-10-01

    We report direct measurement of the modulus change that accompanies the crosslinking of a single molecular monolayer. We measured a change in elastic modulus of 5 x 10{sup 10} dyn/cm{sup 2} as a result of ultraviolet-induced photocrosslinking of a single surface-confined monolayer of the conjugated diacetylenic thiol HS(CH{sub 2}){sub 10}C{triple_bond}CC{triple_bond}C(CH{sub 2}){sub 10}COOH, designated {open_quotes}DAT{close_quotes} hereafter. The modulus measurement was made on a monolayer of DAT chemisorbed upon a gold film on the surface of a 97-MHz ST-quartz surface acoustic wave delay line. The ratio of the changes recorded in SAW velocity and attenuation, approximately 4:1, suggests that the measured effect is mainly a change in the elastic (real) component of the complex shear modulus, viscous changes playing a lesser role. In relation to typical polymer modulus values, the change of 5 x 10{sup 10} dyn/cm{sup 2} is consistent with a change from a rubbery material (G{prime} {approximately} 10{sup 7} - 10{sup 8} dyn/cm{sup 2}) to a fairly rigid, glassy material (G{prime} {approximately} 10{sup 10} dyn/cm{sup 2}), reasonable for comparison of the monolayer in its as-adsorbed and crosslinked forms. This report of the direct SAW-based measurement of the modulus change associated with the crosslinking of a single molecular monolayer is complementary to and consistent with previous in-situ measurements of this process using thickness-shear mode resonators.

  14. Evaluation of a gas chromatograph with a novel surface acoustic wave detector (SAW GC) for screening of volatile organic compounds in Hanford waste tank samples

    SciTech Connect

    Lockrem, L.L.

    1998-01-12

    A novel instrument, a gas chromatograph with a Surface Acoustic Wave Detector (SAW GC), was evaluated for the screening of organic compounds in Hanford tank headspace vapors. Calibration data were developed for the most common organic compounds, and the accuracy and precision were measured with a certified standard. The instrument was tested with headspace samples collected from seven Hanford waste tanks.

  15. Approaching sub-50 nanoradian measurements by reducing the saw-tooth deviation of the autocollimator in the Nano-Optic-Measuring Machine

    NASA Astrophysics Data System (ADS)

    Qian, Shinan; Geckeler, Ralf D.; Just, Andreas; Idir, Mourad; Wu, Xuehui

    2015-06-01

    Since the development of the Nano-Optic-Measuring Machine (NOM), the accuracy of measuring the profile of an optical surface has been enhanced to the 100-nrad rms level or better. However, to update the accuracy of the NOM system to sub-50 nrad rms, the large saw-tooth deviation (269 nrad rms) of an existing electronic autocollimator, the Elcomat 3000/8, must be resolved. We carried out simulations to assess the saw-tooth-like deviation. We developed a method for setting readings to reduce the deviation to sub-50 nrad rms, suitable for testing plane mirrors. With this method, we found that all the tests conducted in a slowly rising section of the saw-tooth show a small deviation of 28.8 to <40 nrad rms. We also developed a dense-measurement method and an integer-period method to lower the saw-tooth deviation during tests of sphere mirrors. Further research is necessary for formulating a precise test for a spherical mirror. We present a series of test results from our experiments that verify the value of the improvements we made.

  16. The effect of purification of single-walled carbon nanotube bundles on the alcohol sensitivity of nanocomposite Langmuir Blodgett films for SAW sensing applications

    NASA Astrophysics Data System (ADS)

    Penza, M.; Tagliente, M. A.; Aversa, P.; Re, M.; Cassano, G.

    2007-05-01

    HiPco (high-pressure CO dissociation process) single-walled carbon nanotube (SWCNT) bundles containing Fe particles were purified in a two-step purification process by thermal annealing in oxygen and post-treatment in HCl. Nanocomposite films of pristine and purified SWCNTs embedded in an organic matrix of cadmium arachidate (CdA) were prepared by a Langmuir-Blodgett (LB) molecular engineering technique with a fixed weight filler content of 75 wt% onto a surface acoustic wave (SAW) transducer operating as an oscillator at a frequency of 433 MHz. The raw and purified samples were characterized at various stages of the purification process using thermogravimetric analysis (TGA), high-resolution transmission electron microscopy (HR-TEM), along with energy-dispersive x-ray spectroscopy (EDS), field emission scanning electron microscopy (FE-SEM) and x-ray diffraction (XRD). Functional characterizations of the SWCNT-nanocomposite-based SAW sensors were investigated towards methanol, isopropanol and ethanol, and demonstrated high sensitivity, reversibility, fast response and ppm level detection at room temperature. Results indicate that the sensitivity of the SAW sensors based on a nanocomposite film of oxygen-annealed SWCNTs is enhanced to the alcohols tested at room temperature. Purification of the SWCNTs in the nanocomposite film affects the SAW sensitivity to alcohol by modulating the sensing properties. The sensing mechanisms are analysed and discussed.

  17. Fatty acid analysis of saw palmetto (Serenoa repens) and pygeum (Prunus africanum) in dietary supplements by mass spectrometry in the selected ion monitoring mode

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Saw palmetto and pygeum are natural products commonly used in dietary supplements for the treatment of enlarged prostate glands. These plant materials are rich in fatty acids, and the fatty acid compositions of both plants are similar. The goal of this study was to develop a gas chromatography-mass ...

  18. 3/18/13 Oracle BI Interactive Dashboards https://ira.dartmouth.edu/analytics/saw.dll?Dashboard&_scid=LHKAECHkLEg 1/5

    E-print Network

    Campbell, Andrew T.

    3/18/13 Oracle BI Interactive Dashboards https://ira.dartmouth.edu/analytics/saw.dll?Dashboard&_scid=LHKAECHkLEg 1/5 Welcome, Andrew T. Campbell! Dashboards - Answers - My Account - Log Out Course: COSC 050 Not Complete Assessment: 3 My Dashboard Course Assessment Course Assessment Page Options

  19. TeV Scale See-Saw Mechanisms of Neutrino Mass Generation, the Majorana Nature of the Heavy Singlet Neutrinos and $\\betabeta$-Decay

    E-print Network

    A. Ibarra; E. Molinaro; S. T. Petcov

    2010-07-14

    It is shown that the Majorana nature of the heavy neutrinos $N_j$ having masses in the range of $M_j \\sim (100 - 1000)$ GeV and present in the TeV scale type I and inverse see-saw scenarios of neutrino mass generation, is unlikely to be observable in the currently operating and future planned accelerator experiments (including LHC) due to the existence of very strong constraints on the parameters and couplings responsible for the corresponding $|\\Delta L| = 2$ processes, $L$ being the total lepton charge. If the heavy Majorana neutrinos $N_j$ are observed and they are associated only with the type I or inverse see-saw mechanisms and no additional TeV scale "new physics", they will behave like Dirac fermions to a relatively high level of precision, being actually pseudo-Dirac particles. The observation of effects proving the Majorana nature of $N_j$ would imply that these heavy neutrinos have additional relatively strong couplings to the Standard Model particles (as, e.g. in the type III see-saw scenario), or that light neutrino masses compatible with the observations are generated by a mechanism other than see-saw (e.g., radiatively at one or two loop level) in which the heavy Majorana neutrinos $N_j$ are nevertheless involved.

  20. Facile synthesis of silver nano/micro-ribbons or saws assisted by polyoxomolybdate as mediator agent and vanadium(IV) as reducing agent.

    PubMed

    Marchal-Roch, Catherine; Mayer, Cédric R; Michel, Aude; Dumas, Eddy; Liu, Feng-Xian; Sécheresse, Francis

    2007-09-28

    Original and effective syntheses of crystalline silver wires and saw bundles, using reduced Keggin polyoxomolybdovanadate (POM) as mediator and reducing agent, were performed in acetonitrile at room temperature; several parameters influencing the final silver 1D-structures, with micrometric length and nanometric thickness, were varied: the nature of the POM, silver salts, vanadium(iv) source and the mild conditions. PMID:17851616

  1. Identification and Affinity-Quantification of ß-Amyloid and ?-Synuclein Polypeptides Using On-Line SAW-Biosensor-Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Slamnoiu, Stefan; Vlad, Camelia; Stumbaum, Mihaela; Moise, Adrian; Lindner, Kathrin; Engel, Nicole; Vilanova, Mar; Diaz, Mireia; Karreman, Christiaan; Leist, Marcel; Ciossek, Thomas; Hengerer, Bastian; Vilaseca, Marta; Przybylski, Michael

    2014-08-01

    Bioaffinity analysis using a variety of biosensors has become an established tool for detection and quantification of biomolecular interactions. Biosensors, however, are generally limited by the lack of chemical structure information of affinity-bound ligands. On-line bioaffinity-mass spectrometry using a surface-acoustic wave biosensor (SAW-MS) is a new combination providing the simultaneous affinity detection, quantification, and mass spectrometric structural characterization of ligands. We describe here an on-line SAW-MS combination for direct identification and affinity determination, using a new interface for MS of the affinity-isolated ligand eluate. Key element of the SAW-MS combination is a microfluidic interface that integrates affinity-isolation on a gold chip, in-situ sample concentration, and desalting with a microcolumn for MS of the ligand eluate from the biosensor. Suitable MS- acquisition software has been developed that provides coupling of the SAW-MS interface to a Bruker Daltonics ion trap-MS, FTICR-MS, and Waters Synapt-QTOF- MS systems. Applications are presented for mass spectrometric identifications and affinity (KD) determinations of the neurodegenerative polypeptides, ß-amyloid (Aß), and pathophysiological and physiological synucleins (?- and ß-synucleins), two key polypeptide systems for Alzheimer's disease and Parkinson's disease, respectively. Moreover, first in vivo applications of ?Syn polypeptides from brain homogenate show the feasibility of on-line affinity-MS to the direct analysis of biological material. These results demonstrate on-line SAW-bioaffinity-MS as a powerful tool for structural and quantitative analysis of biopolymer interactions.

  2. Saw-tooth structures and curved veins related to folds in the south-central Pyrenees (Spain)

    NASA Astrophysics Data System (ADS)

    Bastida, F.; Aller, J.; Lisle, R. J.; Bobillo-Ares, N. C.; Menéndez, C. O.

    2012-01-01

    Two generation of folds ( F1 and F2) and associated structures, developed in the Eocene turbidites of the south-central Pyrenees, are analyzed in this paper. F1 folds are close, have sub-horizontal axes and southwards vergence. They have an associated cleavage S1. Competent layers were folded by layer-parallel shortening, tangential longitudinal strain, some possible flexural flow and an obliquely superimposed homogeneous strain due mainly to simple shear. Flexural slip is also an important mechanism in the whole multilayer. F2 folds are gentle and scarce; they fold the S1 cleavage. Among the structures associated with F1 folds, there are sets of veins with curved form in the competent layers. The displacement of each vein gave rise usually to a step in the layer boundary, so that a set of veins produces a structure that is named "saw-tooth structure". The veins initiated as small faults that made flexural slip difficult and gave rise to a concentration of stress on the steps, leading to an opening of the fractures and a propagation of them along a curved path, as suggested by a simple mechanical model. This propagation agrees with finite element models developed by other authors.

  3. Noise-induced generation of saw-tooth type transitions between climate attractors and stochastic excitability of paleoclimate

    NASA Astrophysics Data System (ADS)

    Alexandrov, Dmitri V.; Bashkirtseva, Irina A.; Ryashko, Lev B.

    2015-11-01

    Motivated by important paleoclimate applications we study a three dimensional model of the Quaternary climatic variations in the presence of stochastic forcing. It is shown that the deterministic system exhibits a limit cycle and two stable system equilibria. We demonstrate that the closer paleoclimate system to its bifurcation points (lying either in its monostable or bistable zone) the smaller noise generates small or large amplitude stochastic oscillations, respectively. In the bistable zone with two stable equilibria, noise induces a complex multimodal stochastic regime with intermittency of small and large amplitude stochastic fluctuations. In the monostable zone, the small amplitude stochastic oscillations localized in the vicinity of unstable equilibrium appear along with the large amplitude oscillations near the stable limit cycle. For the analysis of these noise-induced effects, we develop the stochastic sensitivity technique and use the Mahalanobis metric in the three-dimensional case. To approximate the distribution of random trajectories in Poincare sections, we use a method of confidence ellipses. A spatial configuration of these ellipses is defined by the stochastic sensitivity and noise intensity. The glaciation/deglaciation transitions going between two polar Earth's states with the warm and cold climate become easier and quicker with increasing the noise intensity. Our stochastic analysis demonstrates a near 100 ky saw-tooth type climate self fluctuations known from paleoclimate records. In addition, the enhancement of noise intensity blurs the sharp climate cycles and reduces the glaciation-deglaciation periods of the Earth's paleoclimate.

  4. Field portable detection of VOCs using a SAW/GC system. Final report, June 21, 1994--September 21, 1996

    SciTech Connect

    Chang, F.; Staples, E.J.

    1998-06-01

    This report describes research on a fast GC vapor analysis system which uses a new type of Surface Acoustic Wave detector technology to characterize organic contamination in soil and groundwater. The project was sponsored by the Department of Energy, Morgantown Energy Technology Center, whose mission, in addition to other goals, is the development of tools and methods for characterization, remediation, and monitoring of underground environmental conditions. The research tasks were to demonstrate detectability and specificity of a Surface Acoustic Wave Gas Chromatograph (SAW/GC) to a representative number of VOC materials followed by field demonstrations of the new technology at a DOE site. All tasks of the project were successfully carried out and a fast vapor analysis system based upon a new type of Surface Acoustic Wave detector technology was developed. The prototype analyzer has the ability to characterize organic contamination in soil and groundwater at the part per billion level in less than 10 seconds. The detector is unique because it utilized an uncoated quartz crystal, contrary to current developments of using coated crystals.

  5. Development of Predictive Models for the Specific Energy of Circular Diamond Sawblades in the Sawing of Granitic Rocks

    NASA Astrophysics Data System (ADS)

    Aydin, Gokhan; Karakurt, Izzet; Aydiner, Kerim

    2013-07-01

    This paper presents an experimental study on the sawing of granitic rocks by circular diamond sawblades. The influence of the operating variables and rock properties on the specific energy were initially investigated and analyzed. To determine the most significant operating variables and rock properties influencing the specific energy, statistical analyses were then employed and the models were built for the estimation of specific energy depending on the operating variables and the rock properties. Moreover, the derived models were validated through statistical tests such as the determination coefficient, t-test, F-test, and residuals. The results indicated that the specific energy decreased with the decreasing of peripheral speed and the increasing of traverse speed, cutting depth, and flow rate of cooling fluid, respectively. It was concluded that, rather than the physico-mechanical properties, the mineralogical properties were the dominant rock properties affecting the specific energy. Additionally, the peripheral speed was statistically determined as the most significant operating variable affecting the specific energy. The peripheral speed was followed by the cutting depth, traverse speed, and flow rate of cooling fluid with respect to their level of significance on the specific energy. Furthermore, the model results revealed that the developed models have high potentials as a guidance for practical applications.

  6. Air cavity-based Fabry-Perot interferometer sensor fabricated using a sawing technique for refractive index measurement

    NASA Astrophysics Data System (ADS)

    Jung, Eun Joo; Lee, Woo-Jin; Kim, Myoung Jin; Hwang, Sung Hwan; Rho, Byung Sup

    2014-01-01

    We have demonstrated a refractive index sensor based on a fiber optic Fabry-Perot (FP) interferometer with an open air cavity fabricated using a one-step mechanical sawing technique. The sensor head consists of a short FP cavity near the fiber patch cord tip, which was assembled by joining a ceramic ferrule and a single-mode fiber together. Owing to the open air cavity in the sensor head, various liquid samples with different refractive index can fill in-line air cavity, which makes the device usable as a refractometer. Moreover, due to the sensor head encircled with the robust ceramic ferrule, the device is attractive for sensing measurement in harsh environments. The sensor was tested in different refractive index solutions. The experimental result shows that the attenuation peak wavelength of the sensor is shifted toward a shorter wavelength with increasing refractive index, and the refractive index sensitivity is ˜92.5 nm/refractive index unit (RIU) and 73.75 dB/RIU. The proposed sensor can be used as an in-line refractometer for many potential applications in the sensing field.

  7. Nursing Homes That Increased The Proportion Of Medicare Days Saw Gains In Quality Outcomes For Long-Stay Residents.

    PubMed

    Lepore, Michael; Leland, Natalie E

    2015-12-01

    Nursing homes are increasingly providing rehabilitative care to short-stay residents under Medicare's skilled nursing facility coverage, which is much more generous than Medicaid's coverage for long-stay residents. This shift creates the potential for both beneficial and detrimental effects on outcomes for such residents. Examining nationwide facility-level nursing home data for the period 2007-10, we found that increasing the proportion of Medicare-covered patient days in a nursing home was significantly associated with improvements in the quality of the three outcomes we considered for long-stay residents. We saw significant decreases in the percentages of long-stay residents with daily pain (from 5.1 percent to 3.4 percent), with worsening pressure ulcers (from 2.5 percent to 2.0 percent), and with a decline in performing activities of daily living (from 15.9 percent to 14.9 percent). These findings reinforce previous research indicating that quality outcomes tend to be superior in nursing homes with greater financial resources. They also bolster arguments for financial investments in nursing homes, including increases in Medicaid payment rates, to support better care for long-stay residents. PMID:26643633

  8. Reduction in airborne contamination levels at the 9201-5 Arc Melt sawing operation. A Y-12 Plant 1982 ALARA goal

    SciTech Connect

    Beck, D.E.; West, C.M.

    1983-02-01

    Lowering the uranium airborne contamination level at the two saws in the 9201-5 Arc Melt Area was chosen as a Y-12 Plant As-Low-As-Reasonably-Achievable (ALARA) goal for 1982. This priority was convincingly communicated to those involving by giving specific instructions to suspend saw operations any time there was evidence of a problem until that problem could be corrected. Using control charts on air flow rates into the saw enclosures and pressure drops across filters in the saw ventilation (Delta Phase I) exhaust system, it was possible to decide when filter changes or other adjustments were necessary to maintain the exhaust flow rates needed for improved airborne contamination control. The keeping of these charts, along with the actions taken on the basis of the data gathered, made it possible to meet the goal of reducing airborne contamination levels in 1982, as compared with 1981, although production in the Arc Melt Area increased significantly. These data also showed that use of one brand of filter in the prefilter system resulted in the need to change filters more frequently than when another brand was used. This fact triggered an investigation which revealed the cause for the shorter useful life of that filter and a request that only specifically approved filters be purchased for use in this system. Use of these control data also made it possible to establish that the exhaust system operated more effectively without the Roto-clone hydrostatic pecipitators because exhaust air flow was increased without reduction in filter life.

  9. An Acoustic Charge Transport Imager for High Definition Television Applications: Low-Voltage SAW Amplifiers on Multilayer GaAs/ZnO Substrates

    NASA Technical Reports Server (NTRS)

    Hunt, W. D.; Brennan, K. F.; Summers, C. J.; Cameron, Thomas P.

    1996-01-01

    This thesis addresses the acoustoelectric issues concerning the amplification of surface acoustic waves (SAWs) and the reflection of SAWs from slanted reflector gratings on GaAs, with application to a novel acoustic charge transport (ACT) device architecture. First a simple model of the SAWAMP was developed, which was subsequently used to define the epitaxially grown material structure necessary to provide simultaneously high resistance and high electron mobility. In addition, a segmented SAWAMP structure was explored with line widths on the order of an acoustic wavelength. This resulted in the demonstration of SAWAMPS with an order of magnitude less voltage and power requirements than previously reported devices. A two-dimensional model was developed to explain the performance of devices with charge confinement layers less then 0.5 mm, which was experimentally verified. This model was extended to predict a greatly increased gain from the addition of a ZnO overlay. These overlays were experimentally attempted, but no working devices were reported due to process incompatibilities. In addition to the SAWAMP research, the reflection of SAWs from slanted gratings on GaAs was also studied and experimentally determined reflection coefficients for both 45 deg grooves and Al stripes on GaAs have been reported for the first time. The SAWAMp and reflector gratings were combined to investigate the integrated ring oscillator for application to the proposed ACT device and design parameters for this device have been provided.

  10. The mu - e Conversion in Nuclei, mu --> e gamma, mu --> 3e Decays and TeV Scale See-Saw Scenarios of Neutrino Mass Generation

    E-print Network

    D. N. Dinh; A. Ibarra; E. Molinaro; S. T. Petcov

    2013-08-12

    We perform a detailed analysis of lepton flavour violation (LFV) within minimal see-saw type extensions of the Standard Model (SM), which give a viable mechanism of neutrino mass generation and provide new particle content at the electroweak scale. We focus, mainly, on predictions and constraints set on each scenario from mu --> e gamma, mu --> 3e and mu - e conversion in the nuclei. In this class of models, the flavour structure of the Yukawa couplings between the additional scalar and fermion representations and the SM leptons is highly constrained by neutrino oscillation measurements. In particular, we show that in some regions of the parameters space of type I and type II see-saw models, the Dirac and Majorana phases of the neutrino mixing matrix, the ordering and hierarchy of the active neutrino mass spectrum as well as the value of the reactor mixing angle theta_{13} may considerably affect the size of the LFV observables. The interplay of the latter clearly allows to discriminate among the different low energy see-saw possibilities.

  11. Eating with a saw for a jaw: functional morphology of the jaws and tooth-whorl in Helicoprion davisii.

    PubMed

    Ramsay, Jason B; Wilga, Cheryl D; Tapanila, Leif; Pruitt, Jesse; Pradel, Alan; Schlader, Robert; Didier, Dominique A

    2015-01-01

    The recent reexamination of a tooth-whorl fossil of Helicoprion containing intact jaws shows that the symphyseal tooth-whorl occupies the entire length of Meckel's cartilage. Here, we use the morphology of the jaws and tooth-whorl to reconstruct the jaw musculature and develop a biomechanical model of the feeding mechanism in these early Permian predators. The jaw muscles may have generated large bite-forces; however, the mechanics of the jaws and whorl suggest that Helicoprion was better equipped for feeding on soft-bodied prey. Hard shelled prey would tend to slip anteriorly from the closing jaws due to the curvature of the tooth-whorl, lack of cuspate teeth on the palatoquadrate (PQ), and resistance of the prey. When feeding on soft-bodied prey, deformation of the prey traps prey tissue between the two halves of the PQ and the whorl. The curvature of the tooth-whorl and position of the exposed teeth relative to the jaw joint results in multiple tooth functions from anterior to posterior tooth that aid in feeding on soft-bodied prey. Posterior teeth cut and push prey deeper into the oral cavity, while middle teeth pierce and cut, and anterior teeth hook and drag more of the prey into the mouth. Furthermore, the anterior-posterior edges of the teeth facilitate prey cutting with jaw closure and jaw depression. The paths traveled by each tooth during jaw depression are reminiscent of curved pathways used with slashing weaponry such as swords and knifes. Thus, the jaws and tooth-whorl may have formed a multifunctional tool for capturing, processing, and transporting prey by cyclic opening and closing of the lower jaw in a sawing fashion. PMID:25181366

  12. Nonlinear smooth orthogonal decomposition of kinematic features of sawing reconstructs muscle fatigue evolution as indicated by electromyography.

    PubMed

    Segala, David B; Gates, Deanna H; Dingwell, Jonathan B; Chelidze, David

    2011-03-01

    Tracking or predicting physiological fatigue is important for developing more robust training protocols and better energy supplements and/or reducing muscle injuries. Current methodologies are usually impractical and/or invasive and may not be realizable outside of laboratory settings. It was recently demonstrated that smooth orthogonal decomposition (SOD) of phase space warping (PSW) features of motion kinematics can identify fatigue in individual muscle groups. We hypothesize that a nonlinear extension of SOD will identify more optimal fatigue coordinates and provide a lower-dimensional reconstruction of local fatigue dynamics than the linear SOD. Both linear and nonlinear SODs were applied to PSW features estimated from measured kinematics to reconstruct muscle fatigue dynamics in subjects performing a sawing motion. Ten healthy young right-handed subjects pushed a weighted handle back and forth until voluntary exhaustion. Three sets of joint kinematic angles were measured from the right upper extremity in addition to surface electromyography (EMG) recordings. The SOD coordinates of kinematic PSW features were compared against independently measured fatigue markers (i.e., mean and median EMG spectrum frequencies of individual muscle groups). This comparison was based on a least-squares linear fit of a fixed number of the dominant SOD coordinates to the appropriate local fatigue markers. Between subject variability showed that at most four to five nonlinear SOD coordinates were needed to reconstruct fatigue in local muscle groups, while on average 15 coordinates were needed for the linear SOD. Thus, the nonlinear coordinates provided a one-order-of-magnitude improvement over the linear ones. PMID:21303185

  13. Conventional sawing window Earlysawing

    E-print Network

    Materials Silicates in the SCMs react with the CH from the cement reactions to form additional C-S-H, thus is controlling aluminate* reactions. Little heat is generated, and little physical change occurs in the concrete heat and stiffening of the cement paste mark the beginning of hydration acceleration, which lasts

  14. VITA.SAW

    E-print Network

    ... Class, Race, Life Events and Blood Pressure 1980 - 1981 Research Assistant, ... Validation 1984 - 1985 Principal Investigator, Job Satisfaction in a Changing .... ACADEMIC ADVISEMENT Arbuckle, S. "Noise Levels in Neonatal Nurseries".

  15. Prediction of Performance of Diamond Wire Saw with Respect to Texture Characteristics of Rock / Prognozowanie Wydajno?ci Pracy Strunowej Pi?y Diamentowej W Odniesieniu Do Charakterystyki Tekstury Ska?

    NASA Astrophysics Data System (ADS)

    Ghaysari, N.; Ataei, M.; Sereshki, F.; Mikaiel, R.

    2012-12-01

    In this study, prediction of production rate in diamond wire saw has been investigated. Performance measurements of diamond wire saw carried out in 7 different quarries of carbonate rocks in Iran. For determination textural properties, rock samples were collected from these quarries. At first, a thin section was prepared for each rock and then 5 digital photographs were taken from each section. After this, all images were digitized using AutoCAD software. Then, area, perimeter, longest diameter and shortest diameter were assigned. According to these parameters, all of the other textural characteristics and texture coefficient were determined too. The correlation between sawing rate and textural characteristics were evaluated using multiple and simple regression analyses. Then developed model was validated by P-value test. It was concluded that area, perimeter, diameter equivalent and index of grain size homogeneity are very effective on production rate. Production rate using diamond wire saw can reliably be predicted using developed model.

  16. The Effect of Intraoperative Sounds of Saw and Hammer on Psychological Condition in Patients with Total Knee Arthroplasty: Prospective Randomized Study

    PubMed Central

    Kömürcü, Erkam; Kaymaz, Burak; Gölge, Umut Hatay; Nusran, Gürdal; Göksel, Ferdi; ?ahin, Hasan; Ömür, Dilek; Hanc?, Volkan

    2015-01-01

    Purpose. Surgical procedures are likely to be stressful for patients and their families. Total knee arthroplasty (TKA) is a major surgical procedure used in the treatment of osteoarthritis. During this procedure the sounds of the saw and hammer may irritate the patient and adversely affect mood. The present study examines the effect of these intraoperative sounds during TKA on postoperative mood and anxiety, by comparing two different anesthetic procedures. Methods. A total of 40 patients who underwent TKA for grade IV gonarthrosis participated in the study. Patients were randomly divided into two groups: 20 patients in the general anesthesia group and 20 patients in the spinal anesthesia group. Mood and anxiety changes were evaluated using the Profile of Mood States (POMS) and State-Trait Anxiety Inventory (STAI) instruments, respectively. Results. The postoperative POMS value in the spinal anesthesia group was definitively higher than the general anesthesia group, though the difference in preoperative and postoperative POMS and STAI scores between the two groups was not significant. Conclusion. It would seem that sounds of hammer and saw have no evident negative effect on patient's mood. Regional anesthesia is advisable for TKA patients and appropriate sedation can be administered during the operation if needed. PMID:25793222

  17. An Evaluation of an Aftermarket Local Exhaust Ventilation Device for Suppressing Respirable Dust and Respirable Crystalline Silica Dust from Powered Saws

    PubMed Central

    Garcia, Alberto; Jones, Erica; Echt, Alan S.; Hall, Ronald M.

    2015-01-01

    The objective of this study was to quantify the respirable dust and respirable silica exposures of roofing workers using an electric powered circular saw with an aftermarket local exhaust ventilation attachment to cut concrete roofing tiles. The study was conducted to determine whether the local exhaust ventilation attachment was able to control respirable dust and respirable silica exposure below occupational exposure limits. Time-integrated filter samples and direct reading respirable dust concentrations were evaluated. The local exhaust ventilation consisted of a shroud attached to the cutting plane of the saw; the shroud was then connected to a small electric axial fan, which is intended to collect dust at the point of generation. All sampling was conducted with the control in use. Roofers are defined as those individuals who solely lay tiles. Cutters/roofers are defined as those workers who operate the powered saw to cut tiles and also lay tiles. Respirable dust from this evaluation ranged from 0.13 to 6.59 milligrams per cubic meter (mg/m3) with a geometric mean of 0.38 mg/m3 for roofers and from 0.45 to 3.82 mg/m3 with a geometric mean of 1.84 mg/m3 for cutters/roofers. Cutters/roofers usually handle areas close to crevices, edges, or tips of the roof whereas roofers handle areas where complete tiles can be placed. The respirable dust exposures for all cutters/roofers indicated concentrations exceeding the Occupational Safety and Health Administration’s (OSHA) permissible exposure limit (PEL) for respirable dust containing silica; it was also exceeded for some of the roofers. The respirable silica concentrations ranged from 0.04 to 0.15 mg/m3 with an average of 0.09 mg/m3 for roofers, and from 0.13 to 1.21 mg/m3 with an average of 0.48 mg/m3 for cutters/roofers. As with respirable dust, the respirable silica exposures to cutters/roofers were higher than the exposures for roofers. PMID:25148513

  18. An evaluation of an aftermarket local exhaust ventilation device for suppressing respirable dust and respirable crystalline silica dust from powered saws.

    PubMed

    Garcia, Alberto; Jones, Erica; Echt, Alan S; Hall, Ronald M

    2014-01-01

    The objective of this study was to quantify the respirable dust and respirable silica exposures of roofing workers using an electric-powered circular saw with an aftermarket local exhaust ventilation attachment to cut concrete roofing tiles. The study was conducted to determine whether the local exhaust ventilation attachment was able to control respirable dust and respirable silica exposure below occupational exposure limits (OELs). Time-integrated filter samples and direct reading respirable dust concentrations were evaluated. The local exhaust ventilation consisted of a shroud attached to the cutting plane of the saw; the shroud was then connected to a small electric axial fan, which is intended to collect dust at the point of generation. All sampling was conducted with the control in use. Roofers are defined as those individuals who only lay tiles. Cutters/roofers are defined as those workers who operate the powered saw to cut tiles and also lay tiles. Respirable dust from this evaluation ranged from 0.13 to 6.59 milligrams per cubic meter (mg/m(3)) with a geometric mean of 0.38 mg/m(3) for roofers and from 0.45 to 3.82 mg/m(3) with a geometric mean of 1.84 mg/m(3) for cutters/roofers. Cutters/roofers usually handle areas close to crevices, edges, or tips of the roof whereas roofers handle areas where complete tiles can be placed. The respirable dust exposures for all cutters/roofers indicated concentrations exceeding the Occupational Safety and Health Administration's (OSHA) permissible exposure limit (PEL) for respirable dust containing silica; it was also exceeded for some of the roofers. The respirable silica concentrations ranged from 0.04 to 0.15 mg/m(3) with a geometric mean of 0.09 mg/m(3) for roofers, and from 0.13 to 1.21 mg/m(3) with a geometric mean of 0.48 mg/m(3) for cutters/roofers. As with respirable dust, the respirable silica exposures for cutters/roofers were higher than the exposures for roofers. PMID:25148513

  19. Using Nano-mechanics and Surface Acoustic Wave (SAW) for Disease Monitoring and Diagnostics at a Cellular Level in Red Blood Cells

    NASA Astrophysics Data System (ADS)

    Sivanantha, Ninnuja; Ma, Charles; Collins, David J.; Sesen, Muhsincan; Brenker, Jason; Coppel, Ross L.; Neild, Adrian; Alan, Tuncay

    A popular approach to monitoring diseases and their diagnosis is through biological, pathological or immunological characterization. However, at a cellular level progression of certain diseases manifests itself through mechanical effects as well. Here, we present a method which exploits localised flow; surface acoustic wave (SAW) induced acoustic streaming in a 9 ?L droplet to characterize the adhesive properties of red blood cells (healthy, gluteraldehyde treated and malaria infected) in approximately 50 seconds. Our results show a 79% difference in cell mobilization between healthy malaria infected RBCs (and a 39% difference between healthy and treated ones), indicating that the method can serve as a platform for rapid clinical diagnosis; where separation of two or more different cell populations in a mixed solution is desirable. It can also act as a key biomarker for monitoring some diseases offering quantitative measures of disease progression and response to therapy.

  20. Precision distance measurement using a two-photon absorption process in a silicon avalanche photodiode with saw-tooth phase modulation.

    PubMed

    Tanaka, Yosuke; Tominaka, Seiji; Kurokawa, Takashi

    2015-10-01

    We present a novel configuration of a precision laser distance measurement based on the two-photon absorption (TPA) photocurrent from a silicon avalanche photodiode (Si-APD). The proposed system uses saw-tooth phase modulation, known as serrodyne modulation, in order to shift the frequency of the reference light from that of the probe light. It suppresses the coherent interference noise between the probe and the reference. The serrodyne modulation also enables lock-in detection of the TPA photocurrent. Furthermore, it contributes to the reduction of the system components. The precision measurement is experimentally demonstrated by measuring a fiber length difference of 2.6 m with a standard deviation of 27 ?m under constant temperature. The high-precision displacement measurement is also demonstrated by measuring the temperature-induced change in the optical path length difference of a fiber interferometer. PMID:26479662

  1. The visual response properties of neurons in the nucleus of the basal optic root of the northern saw-whet owl (Aegolius acadicus).

    PubMed

    Wylie, D R; Shaver, S W; Frost, B J

    1994-01-01

    The nucleus of the basal optic root (nBOR) in birds is a component of the accessory optic system (AOS) which is involved in the analysis of visual flowfields normally resulting from self-motion. Using standard extracellular techniques, we recorded from 81 single-unit and multi-unit clusters in the nBOR of the northern saw-whet owl, Aegolius acadicus, an avian species that has a visual system with frontal emphasis. These cells responded best to large patterns of random dots moving either upward (52%), downward (31%) or nasal to temporal (N-T; contralateral visual field; 15%). Only 2 units (2%) preferred temporal to nasal motion. 'Up' units were found in the dorsal portion of the nucleus whereas 'Down' units were located more ventrally. The N-T units were found in both the lateral margin of the nucleus and ventral to the Down units in the lateral half of the nucleus. About half of the units tested (10/19) responded to stimulation of the ipsilateral as well as the contralateral eye. For all but one cell, the direction preference of both eyes was the same in visual space. When compared with previous studies of pigeons (Columba livia) and chickens (Gallus domesticus), these findings reveal that the nBOR in all three avian species have important similarities with respect to direction preference and functional compartmentalization. Furthermore, the high proportion of binocular neurons found in the nBOR of the saw-whet owl is similar to the condition generally reported in frontal eyed mammals and hence may reflect adaptation. PMID:8306188

  2. Investigations of AlN thin film crystalline properties in a wide temperature range by in situ X-ray diffraction measurements: Correlation with AlN/sapphire-based SAW structure performance.

    PubMed

    Aït Aïssa, Keltouma; Elmazria, Omar; Boulet, Pascal; Aubert, Thierry; Legrani, Ouadra; Mangin, Denis

    2015-07-01

    Aluminum nitride on sapphire is a promising substrate for SAW sensors operating at high temperatures and high frequencies. To get a measure of the suitability and temperature stability of such devices, an experimental relationship between the SAW performance and the structural properties of the AlN thin films was investigated in the temperature range between the ambient temperature and 1000°C. The crystalline structure of the AlN films was examined in situ versus temperature by X-ray diffraction. The results reveal that the AlN films remain (002) oriented even at high temperatures. A gradual increase of the tensile stress in the film due to the thermal expansion mismatch with the substrate has been observed. This increase accelerates around 600°C as the AlN film crystalline quality improves. This phenomenon could explain the amelioration in the SAW performance of AlN/sapphire devices observed previously between 600°C and 850°C. At higher temperatures, surface oxidation of the AlN films reduces the SAW performance. The potential of ZnO thin films as protective layers was finally examined. PMID:26168184

  3. Figure 1: U.S. birds struck by aircra5 by year. 2012 saw the highest number of bird strikes on U.S. civilian aircra5s in one year: 10,343.

    E-print Network

    Brown, Sally

    Figure 1: U.S. birds struck by aircra5 by year. 2012 saw the highest number of bird strikes on U.S. civilian aircra5s in one year: 10,343. Figure and birds. ExploraIon of the InteracIons Between Seaplane Pilots and Birds. Sean

  4. A wideband multi-mode SAW filter employing pitch-modulated IDTs on Cu-grating/15 degrees YX-LiNbO3-substrate structure.

    PubMed

    Hashimoto, Ken-ya; Miyamoto, Takashi; Shimada, Ken-ta; Omori, Tatsuya; Yamaguchi, Masatsune

    2010-05-01

    This paper describes an attempt to develop extremely wideband multi-mode surface acoustic wave (MMS) filters in the gigahertz range. The Cu-grating/15 degrees YX-LiNbO3 (15-LN)-substrate structure is employed. First, a design tool developed for the present purpose is detailed. Precise simulation is performed using a modified coupling-of-modes model, in which the coupling between propagating surface and bulk acoustic waves is taken into account. Parameters necessary for the simulation are determined experimentally. Next, this simulation tool is used to design a wideband MMS filter employing pitch-modulated IDTs proposed by the authors. It is shown that a fractional bandwidth of more than 12% is achievable by successfully using six SAW resonances supported in the MMS structure. The designed MMS filter was fabricated on a Cu-grating/15-LN-substrate structure. The passband width of 12.6% and the minimum insertion loss of 1.2 dB were experimentally obtained around 850 MHz. The measured result was in good agreement with the simulation. PMID:20442030

  5. The Different Sensitive Behaviors of a Hydrogen-Bond Acidic Polymer-Coated SAW Sensor for Chemical Warfare Agents and Their Simulants

    PubMed Central

    Long, Yin; Wang, Yang; Du, Xiaosong; Cheng, Luhua; Wu, Penglin; Jiang, Yadong

    2015-01-01

    A linear hydrogen-bond acidic (HBA) linear functionalized polymer (PLF), was deposited onto a bare surface acoustic wave (SAW) device to fabricate a chemical sensor. Real-time responses of the sensor to a series of compounds including sarin (GB), dimethyl methylphosphonate (DMMP), mustard gas (HD), chloroethyl ethyl sulphide (2-CEES), 1,5-dichloropentane (DCP) and some organic solvents were studied. The results show that the sensor is highly sensitive to GB and DMMP, and has low sensitivity to HD and DCP, as expected. However, the sensor possesses an unexpected high sensitivity toward 2-CEES. This good sensing performance can’t be solely or mainly attributed to the dipole-dipole interaction since the sensor is not sensitive to some high polarity solvents. We believe the lone pair electrons around the sulphur atom of 2-CEES provide an electron-rich site, which facilitates the formation of hydrogen bonding between PLF and 2-CEES. On the contrary, the electron cloud on the sulphur atom of the HD molecule is offset or depleted by its two neighbouring strong electron-withdrawing groups, hence, hydrogen bonding can hardly be formed. PMID:26225975

  6. The Different Sensitive Behaviors of a Hydrogen-Bond Acidic Polymer-Coated SAW Sensor for Chemical Warfare Agents and Their Simulants.

    PubMed

    Long, Yin; Wang, Yang; Du, Xiaosong; Cheng, Luhua; Wu, Penglin; Jiang, Yadong

    2015-01-01

    A linear hydrogen-bond acidic (HBA) linear functionalized polymer (PLF), was deposited onto a bare surface acoustic wave (SAW) device to fabricate a chemical sensor. Real-time responses of the sensor to a series of compounds including sarin (GB), dimethyl methylphosphonate (DMMP), mustard gas (HD), chloroethyl ethyl sulphide (2-CEES), 1,5-dichloropentane (DCP) and some organic solvents were studied. The results show that the sensor is highly sensitive to GB and DMMP, and has low sensitivity to HD and DCP, as expected. However, the sensor possesses an unexpected high sensitivity toward 2-CEES. This good sensing performance can't be solely or mainly attributed to the dipole-dipole interaction since the sensor is not sensitive to some high polarity solvents. We believe the lone pair electrons around the sulphur atom of 2-CEES provide an electron-rich site, which facilitates the formation of hydrogen bonding between PLF and 2-CEES. On the contrary, the electron cloud on the sulphur atom of the HD molecule is offset or depleted by its two neighbouring strong electron-withdrawing groups, hence, hydrogen bonding can hardly be formed. PMID:26225975

  7. Understanding processing-microstructure-properties relationships in Bi2Sr2CaCu2Ox/Ag round wires and enhanced transport through saw-tooth processing

    NASA Astrophysics Data System (ADS)

    Naderi, Golsa; Liu, Xiaotao; Nachtrab, William; Schwartz, Justin

    2013-10-01

    Superconducting magnets generating magnetic fields above 25 T are needed for many scientific applications. Due to fundamental limitations in NbTi and Nb3Sn, such high-field superconducting magnets require alternative high-field conductors. One candidate conductor is round wire composites of Bi2Sr2CaCu2Ox sheathed in a Ag-alloy matrix (Bi2212/Ag). The performance of such wires is sensitive to the heat treatment, so improvements in the critical current density (Jc) require a thorough understanding of the processing-structure-properties relationships. Here we present a two-part study. In part I, a new heat treatment approach, saw-tooth processing (STP), is introduced based upon previous results showing that Bi2212 nucleation is site-saturation limited. The microstructural evolution of Bi2212 filaments during processing is discussed and results from STP are compared with those from other processes. STP is shown to increase Jc by 120% and 70% relative to partial-melt processing at 5 T and self-field respectively, and by 65% and 34% relative to split-melt processing. Yet STP also complicates the heat treatment by introducing a number of new heat treatment variables that affect the grain morphology, phase assemblage and oxygen content of the Bi2212 filaments and thus the transport properties. In part II, the effects of STP heat treatment parameters on the microstructure and transport properties are discussed. It is shown that wires with the highest transport critical current densities primarily have filaments with two types of microstructures, one comprised primarily of highly textured Bi2212 grains, and another with a noticeable amount of Bi2Sr2CuOx with the Bi2212.

  8. I ``Saw'' Newton's Three Laws

    NASA Astrophysics Data System (ADS)

    Shaw, Mike

    2012-11-01

    Would you like to build an inexpensive, highly visible, quickly assembled device that dramatically illustrates Newton's three laws of motion? This model incorporates sturdiness, high-profile visibility, and a student interest component that is sure to capture and hold their attention.

  9. SAWFAST - a SAW diffraction channelizer

    SciTech Connect

    Elliott, J.H.; Stokes, R.B.; Yen, K.H.

    1986-09-01

    One important aspect of modern electronic warfare systems is the ability to sort signals according to their frequency. This paper describes a novel surface acoustic wave channelizer to perform this sorting at IF frequencies. The operating principles are analogous to an optical diffraction grating. Prototype devices that cover a 260 MHz bandwidth with a sidelobe rejection to about 40 dB are described.

  10. Clay Swelling and Particle Redistribution in a Saw-Cut Fracture in the Paintbrush Nonwelded Unit of the Topopah Spring Tuff

    NASA Astrophysics Data System (ADS)

    Kneafsey, T. J.; Oldenburg, C. M.; Salve, R.

    2001-12-01

    Flow through the altered nonwelded tuffs of the Paintbrush unit (PTn) at Yucca Mountain, Nevada, is thought to be primarily through the highly porous rock matrix. Due to matrix flow and the sloping structure of the unit, the PTn is thought to divert downward-flowing water laterally. However, large fractures and faults in the PTn may also provide pathways for flow through the unit and these may prevent or interrupt lateral flow through the unit. In field tests where water was released directly into a fault in the altered PTn, flow rates declined over time. To evaluate processes such as matrix swelling and particle redistribution that might explain this decline, we performed a laboratory experiment using a 12 cm diameter x 21.6 cm long core with an axial saw-cut fracture. The core was extracted from the argillic Tpbt2C layer. We monitored permeability, inlet and outlet flow rate, and the volume change of the rock core (contained in a pressure vessel) while flow occurred through the fracture and matrix. Water containing various sodium chloride concentrations (1 M, 0.5 M, 0 M, and 1M) was flowed through the fracture to observe the effect of salt concentration on fracture permeability in the smectite-rich rock core. The sample swelled initially, despite the high salt concentration (1 M) of the inlet water. The permeability of the fracture decreased with declining salt concentration and increased with increasing salt concentration indicating that clay swelling decreased fracture aperture and reduced the flow rate. Particle redistribution (dispersion and flocculation) was indicated by particles in the effluent. Particles from lower salinity flows remained suspended in the effluent container, while those from higher salinity flows settled more easily, were larger, and more compact. If particle redistribution were controlling the flow, the permeability should have increased during low salinity water flow because of particle erosion. This work was supported by the Director, Office of Civilian Radioactive Waste Management, U.S. Department of Energy, through Memorandum Purchase Order EA9013MC5X between Bechtel SAIC Company, LLC and the Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley Lab). The support is provided to Berkeley Lab through the U.S. Department of Energy Contract No. DE-AC03-76SF00098.

  11. 29 CFR 570.65 - Occupations involved in the operations of circular saws, band saws, guillotine shears, chain saws...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Between 16 and 18 Years of Age or Detrimental to Their Health or Well-Being § 570.65 Occupations involved in the operations of...knives mounted on a rotating chipper disc or drum, and a power plant used to reduce to chips or shred such materials as tree...

  12. What Brown saw and you can too

    NASA Astrophysics Data System (ADS)

    Pearle, Philip; Collett, Brian; Bart, Kenneth; Bilderback, David; Newman, Dara; Samuels, Scott

    2010-12-01

    A discussion of Robert Brown's original observations of particles ejected by pollen of the plant Clarkia pulchella undergoing what is now called Brownian motion is given. We consider the nature of those particles and how he misinterpreted the Airy disk of the smallest particles to be universal organic building blocks. Relevant qualitative and quantitative investigations with a modern microscope and with a "homemade" single lens microscope similar to Brown's are presented.

  13. Wireless SAW Sensors Having Integrated Antennas

    NASA Technical Reports Server (NTRS)

    Gallagher, Mark (Inventor); Malocha, Donald C. (Inventor)

    2015-01-01

    A wireless surface acoustic wave sensor includes a piezoelectric substrate, a surface acoustic wave device formed on the substrate, and an antenna formed on the substrate. In some embodiments, the antenna is formed on the surface of the substrate using one or more of photolithography, thin film processing, thick film processing, plating, and printing.

  14. Fractional moment methods for Anderson localization with SAW representation

    NASA Astrophysics Data System (ADS)

    Suzuki, Fumika

    2013-03-01

    The Green function contains much information about physical systems. Mathematically, the fractional moment method (FMM) developed by Aizenman and Molchanov connects the Green function and the transport of electrons in the Anderson model. Recently, it has been discovered that the Green function on a graph can be represented using self-avoiding walks on a graph, which allows us to connect localization properties in the system and graph properties. We discuss FMM in terms of the self-avoiding walks on a general graph, the only general condition being that the graph has a uniform bound on the vertex degree.

  15. Pulse-mode temperature sensing with langasite SAW devices

    E-print Network

    Greve, David.W.

    an interdigitated transducer (IDT), consisting of thin metal electrode with equal spacing and width, to generate,6]. The electromechanical coefficient of langasite is about 0.4%, comparable to quartz. It has no phase transition measurement with an RF signal generator and signal analyzer offers better resolution by measuring the phase

  16. Language and Culture: Two for the See-Saw.

    ERIC Educational Resources Information Center

    Elliott, Jacqueline

    A number of ways to interweave the teaching of culture with the teaching of language skills at all levels are suggested. In considering the manners by which to present selected cultural patterns at the different levels, the article cites three methods by which teaching culture can be incorporated easily into the language teaching activities of…

  17. See What Galileo Saw - And More! With Online Telescopes

    NASA Astrophysics Data System (ADS)

    Steel, Simon J.

    2008-05-01

    This presentation introduces the Galileo activity from MicroObservatory, an online robotic telescope network that can deliver images free of charge and within 24 hours to anyone with an email address. I will describe the MicroObservatory network, its free image processing software, and examples of how users can follow in Galileo's footsteps by making their own observations and comparing them both to Galileo's sketches and images from modern space telescopes and planetary missions. I will also describe a new "Observing with NASA” portal to MicroObservatory that is being developed for IYA.

  18. See What Galileo Saw---And More! With Online Telescopes

    NASA Astrophysics Data System (ADS)

    Steel, S. J.

    2008-11-01

    This presentation introduces the Galileo activity from MicroObservatory, an online robotic telescope network that can deliver images free of charge and within 24 hours to anyone with an email address. I will describe the MicroObservatory network, its free image processing software, and examples of how users can follow in Galileo's footsteps by making their own observations and comparing them both to Galileo's sketches and images from modern space telescopes and planetary missions. I will also describe a new ``Observing with NASA'' portal to MicroObservatory that is being developed for IYA.

  19. Congenital Achiasma and See-Saw Nystagmus in VACTERL Syndrome

    E-print Network

    Dumoulin, Serge O.

    normal. Goldmann visual fields were slightly restricted bilaterally, left greater than right. Color of Ophthalmology (SP, YJL), Psychology (SD, BAW), and Radiology (NF), Stanford University School of Medicine, Stanford, California. Current affiliation of S.D.: Helmholtz Institute, Experimental Psychology, Utrecht

  20. Temperature and Strain Coefficient of Velocity for Langasite SAW Devices

    NASA Technical Reports Server (NTRS)

    Wilson, W. C.; Atkinson, G. M.

    2013-01-01

    Surface Acoustic Wave sensors on Langasite substrates are being investigated for aerospace applications. Characterization of the Langasite material properties must be performed before sensors can be installed in research vehicles. The coefficients of velocity for both strain and temperature have been determined. These values have also been used to perform temperature compensation of the strain measurements.

  1. d self-avoiding walk SAW mean square displacement exponent

    E-print Network

    Hattori, Tetsuya

    W0 L(w)=13 W0: SAP on dSG (Self-Avoiding Path) w : Z+ G L(w) = inf{i | w(j) = w(i), j i} W0 = {w, 3: Hattori-Hattori-Kusuoka dSG, d = 2, 3, dSG, d = 4, 5, 6, · · · dSG, d = 2, 3, SAP SAP path dSG SAP SAP #12;( ) (i) (path ) ( ) (ii) (iii) dSG SAP (re- cursion) #12;W(1) (1) S(1)=3 S(2)=0 W(2) (1) S

  2. Performance evaluation of algorithms for SAW-based temperature measurement.

    PubMed

    Schuster, Stefan; Scheiblhofer, Stefan; Reindl, Leonhard; Stelzer, Andreas

    2006-06-01

    Whenever harsh environmental conditions such as high temperatures, accelerations, radiation, etc., prohibit usage of standard temperature sensors, surface acoustic wave-based temperature sensors are the first choice for highly reliable wireless temperature measurement. Interrogation of these sensors is often based on frequency modulated or frequency stepped continuous wave-based radars (FMCW/FSCW). We investigate known algorithms regarding their achievable temperature accuracy and their applicability in practice. Furthermore, some general rules of thumb for FMCW/FSCW radar-based range estimation by means of the Cramer-Rao lower bound (CRLB) for frequency and phase estimation are provided. The theoretical results are verified on both simulated and measured data. PMID:16846150

  3. Surface photovoltage measurements and finite element modeling of SAW devices.

    SciTech Connect

    Donnelly, Christine

    2012-03-01

    Over the course of a Summer 2011 internship with the MEMS department of Sandia National Laboratories, work was completed on two major projects. The first and main project of the summer involved taking surface photovoltage measurements for silicon samples, and using these measurements to determine surface recombination velocities and minority carrier diffusion lengths of the materials. The SPV method was used to fill gaps in the knowledge of material parameters that had not been determined successfully by other characterization methods. The second project involved creating a 2D finite element model of a surface acoustic wave device. A basic form of the model with the expected impedance response curve was completed, and the model is ready to be further developed for analysis of MEMS photonic resonator devices.

  4. Stress Analysis of Marble Sawing Disc in Cutting Process

    NASA Astrophysics Data System (ADS)

    Ucun, Ismail; Colakoglu, Mehmet; Tasgetiren, Suleyman

    In this study, stresses in the marble cutting disc are investigated by finite element method. Normal and tangential forces in stress analysis are considered and critical stress regions are found. Depending on the chosen depth of cut, (i.e., 17.5, 40, 70 and 108 mm) these forces are applied in different values taken from an experimental study. In addition, the equivalent stress is also tried to determine under shock loading which occurs depending on working conditions and hardness of the marble. The analysis is carried out at four different cutting speeds. The results under the normal and shock loads are compared and the possible failure regions are studied.

  5. The Sun as you never saw it before

    NASA Astrophysics Data System (ADS)

    1997-02-01

    The remarkable images come from SOHO's visible-light coronagraph LASCO. It masks the intense rays from the Sun's surface in order to reveal the much fainter glow of the solar atmosphere, or corona. Operated with its widest field of view, in its C3 instrument, LASCO's unprecedented sensitivity enables it to see the thin ionized gas of the solar wind out to the edges of the picture, 22 million kilometres from the Sun's surface. Many stars are brighter than the gas, and they create the background scene. The results alter human perceptions of the Sun. Nearly 30 years ago, Apollo photographs of the Earth persuaded everyone of what until then they knew only in theory, that we live on a small planet. Similarly the new imagery shows our motion in orbit around the Sun, and depicts it as one star among - yet close enough to fill the sky emanations that engulf us. For many centuries even astrologers knew that the Sun was in Sagittarius in December and drifting towards the next zodiacal constellation, Capricornus. This was a matter of calculation only, because the Sun's own brightness prevented a direct view of the starfield. The SOHO-LASCO movie makes this elementary point of astronomy a matter of direct observation for the first time. The images are achievable only from a vantage point in space, because the blue glow of the Earth's atmosphere hides the stars during the day. A spacial allocation of observing time, and of data tranmission from the SOHO spacecraft, enabled the LASCO team to obtain large numbers of images over the period 22-28 December 1996. Since then, a sustained effort in image processing, frame by frame, has achieved a result of high technical and aesthetic quality. Only now is the leader of the LASCO team, Guenter Brueckner of the US Naval Research Laboratory, satisfied with the product and ready to authorize its release. "I spend my life examining the Sun," Brueckner says, "but this movie is a special thrill. For a moment I forget the years of effort that went into creating LASCO and SOHO, and leave aside the many points of scientific importance in the images, I am happy to marvel at a new impression of the busy star that gives us life, and which affects our environment in many ways that we are only now beginning to understand." Transatlantic cooperation The Solar and Heliospheric Observatory SOHO is a project of international cooperation between ESA and NASA. ESA and the European aerospace industry built the spacecraft, and NASA launched it on 2 December 1995. Operating 1,500,000 kilometres out on the sunward side of the Earth, near the position called Lagrangian point L1, SOHO has an uninterrupted view of the Sun from an undisturbed vantage point, and a precision of pointing which makes delicate observations possible. SOHO carries 12 sets of instruments provided by scientific teams, each led by a European or an American principal investigator. They study the solar interior by helioseismology, the solar atmosphere seen by ultraviolet and visible light, and the solar wind and energetic particles. There is much transatlantic collaboration within the various teams. Besides the Naval Research Laboratory in Washington, LASCO involves the Max-Planck-Institüt für Aeronomie at Lindau (Germany), the Unversity of Birmingham (England) and Laboratoire d'Astronomie Spatiale at Marseille (France). Sharing LASCO's electronic systems, and many operations and analyses, is SOHO's extreme ultraviolet imager EIT. This is the responsibility of a team led from Orsay (France) and it observes activity in the Sun's hot atmosphere related to the wider events seen by LASCO. Roger Bonnet, who presides over the multinational effort as ESA's Director of Science, shares the enthusiasm for the Christmas movie. "For the first time we see the Sun clearly among the stars, thanks to SOHO and LASCO," Bonnet comments. "Now when we say that the Sun is a typical star, and a key to understanding the whole Universe, that is no longer a theoretical statement but something everyone can see. The quality of the images c

  6. 29 CFR 570.65 - Occupations involved in the operations of circular saws, band saws, and guillotine shears (Order...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Between 16 and 18 Years of Age or Detrimental to Their Health or Well-Being § 570.65 Occupations involved in the operations of circular...knives mounted on a rotating chipper disc or drum, and a power plant used to reduce to chips or shred such materials as tree...

  7. 29 CFR 570.65 - Occupations involved in the operations of circular saws, band saws, and guillotine shears (Order...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS CHILD LABOR REGULATIONS, ORDERS AND... operator of or helper on the following power-driven fixed or portable machines except machines equipped... discs (Order 14). (a) * * * (2) The occupations of operator of or helper on the following...

  8. Warpage Analysis of Silicon Wafer in Ingot Slicing by Wire-Saw Machine

    NASA Astrophysics Data System (ADS)

    Yamada, Toshiro; Kinai, Fumiaki; Ichikawa, Takesh; Yokoyama, Atsushi; Fukunaga, Moritaka; Ohshita, Takashi

    2004-06-01

    It is possible thermal expansion from heat generation by slicing deforms a single-crystal silicon ingot but the authors can find no report on the point. In addition, numerical analysis is useful to clarify the mechanism of wafer warping but no paper has been reported the numerical analysis from the start to end of the wafer slicing process. The authors carried out experiments for the wafer slicing. In addition, a finite element analysis was carried out in order to solve the warping mechanism from the start to end of the wafer slicing process. The warp of wafer in the vertical direction was 6.05 ? m in the experiment whereas the warp in the finite element analysis was 5.30 ? m. The result by the finite element analysis gave good agreement with experimental one. This paper suggests that thermal expansion of the ingot has great influence on the warp of wafer.

  9. Veni,Vidi, Suffragi I came,I saw,I voted.

    E-print Network

    Filman, Robert E.

    . This is in the face of a system with a large experi- mental error -- one that lost four to six million votes from of Parliament and city coun- cilor. I, on the other hand, vote for (and this is just off the top of my head of supervi- sors, various county officials like the assessor and coroner, the city council (which elects its

  10. PSAW/MicroSWIS [Microminiature Surface Acoustic Wave (SAW) based Wirelesss Instrumentation System

    NASA Technical Reports Server (NTRS)

    Heermann, Doug; Krug, Eric

    2004-01-01

    This Final Report for the PSAW/MicroSWIS Program is provided in compliance with contract number NAS3-01118. This report documents the overall progress of the program and presents project objectives, work carried out, and results obtained. Program Conceptual Design Package stated the following objectives: To develop a sensor/transceiver network that can support networking operations within spacecraft with sufficient bandwidth so that (1) flight control data, (2) avionics data, (3) payload/experiment data, and (4) prognostic health monitoring sensory information can flow to appropriate locations at frequencies that contain the maximum amount of information content but require minimum interconnect and power: a very high speed, low power, programmable modulation, spread-spectrum radio sensor/transceiver.

  11. They saw a movie: Long-term memory for an extended audiovisual narrative

    E-print Network

    Dudai, Yadin

    -confidence recognition performance was a reliable index of memory throughout the measured time span, cued recall accuracy differential memory performance profiles according to time since encoding. We also used the data to propose are capable of simulating aspects of real-life experi- ences by fusing multimodal perception with emotional

  12. Langasite SAW Device with Gas-Sensitive Layer Peng Zheng1,2

    E-print Network

    Greve, David.W.

    University, Pittsburgh, PA, USA 4 Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, USA 4 Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA, USA 5,3 , Irving Oppenheim1,4 1 National Energy Technology Laboratory, Pittsburgh, PA, USA 2 Physics Department

  13. Properdin and Factor H: Opposing Players on the Alternative Complement Pathway “See-Saw

    PubMed Central

    Kouser, Lubna; Abdul-Aziz, Munirah; Nayak, Annapurna; Stover, Cordula M.; Sim, Robert B.; Kishore, Uday

    2013-01-01

    Properdin and factor H are two key regulatory proteins having opposite functions in the alternative complement pathway. Properdin up-regulates the alternative pathway by stabilizing the C3bBb complex, whereas factor H downregulates the pathway by promoting proteolytic degradation of C3b. While factor H is mainly produced in the liver, there are several extrahepatic sources. In addition to the liver, factor H is also synthesized in fetal tubuli, keratinocytes, skin fibroblasts, ocular tissue, adipose tissue, brain, lungs, heart, spleen, pancreas, kidney, muscle, and placenta. Neutrophils are the major source of properdin, and it is also produced by monocytes, T cells and bone marrow progenitor cell line. Properdin is released by neutrophils from intracellular stores following stimulation by N-formyl-methionine-leucine-phenylalanine (fMLP) and tumor necrosis factor alpha (TNF-?). The HEP G2 cells derived from human liver has been found to produce functional properdin. Endothelial cells also produce properdin when induced by shear stress, thus is a physiological source for plasma properdin. The diverse range of extrahepatic sites for synthesis of these two complement regulators suggests the importance and need for local availability of the proteins. Here, we discuss the significance of the local synthesis of properdin and factor H. This assumes greater importance in view of recently identified unexpected and novel roles of properdin and factor H that are potentially independent of their involvement in complement regulation. PMID:23630525

  14. Introduction `...as the dredge cleared the surface, we saw it full and

    E-print Network

    in color, and from 6 to 7 inches across the legs.' From South with Mawson by C. F. Laserson, zoologist principles that govern the evolution of body size. Body size is a key determinant of how organisms interact with the earliest expeditions to the poles, over 100years ago, scientists have compiled an impressive list of polar

  15. Iwent to the library and I saw an astronomy book. I looked at it...I

    E-print Network

    Rhoads, James

    field trips and special class- room speakers to museum visits and public events. Reaching Out Engagement.asu.edu/node/1146 Kip Hodges: The Scientist as Storyteller Watch the video: humanities.asu.edu/node/962 SESE Source heavily as they are dependent upon laboratory in- struction and educational outings, necessary outlets

  16. The Income Volatility See-Saw: Implications for School Lunch. Economic Research Report Number 23

    ERIC Educational Resources Information Center

    Newman, Constance

    2006-01-01

    Income volatility challenges the effectiveness of the safety net that USDA food assistance programs provide low-income families. This study examines income volatility among households with children and the implications of volatility for eligibility in the National School Lunch Program (NSLP). The results show that income volatility was higher for…

  17. Supporting Professionalism: See-Saw Politics and the Paradox of Deregulation

    ERIC Educational Resources Information Center

    Hillier, Yvonne; Appleby, Yvon

    2012-01-01

    How can one capture the good practice within the further education sector and identify how best to develop the workforce? This conundrum has taxed government and professionals within the sector for decades. The introduction of Preparing to Teach in the Lifelong Learning Sector (PTLLS), the Certificate (CTLLS) and Diploma (DTLLS) in 2007 was the…

  18. They Went, They Saw, They Learned: Medical Students' Reflections on Community Clinic Visits

    ERIC Educational Resources Information Center

    Beylefeld, Adriana A.

    2014-01-01

    Medicine has become a profession with increasing accountability to the needs of society. To meet this need, real-world, community-located experiences and reflection are frequently used to promote students' learning and personal growth. This article reports first-year medical students' reflective writing after visiting a primary…

  19. Are Outer Hair Cells Pressure Sensors? Basis of a SAW Model of the Cochlear Amplifier

    NASA Astrophysics Data System (ADS)

    Bell, A.

    2003-02-01

    Because outer hair cells bear stereocilia it is natural to assume that, like inner hair cells, the unique stimulus to which they react is stereociliar deflection. But is this long-standing assumption necessarily true? This work considers a number of recurring anomalies which have appeared in the literature over the years and concludes that their common underlying feature is an OHC response to pressure. At low SPLs, intracochlear fluid pressure could provide an additional, and perhaps dominant, stimulus for driving the cochlear amplifier.

  20. Utility Theory for Evaluation of Optimal Process Condition of SAW: A Multi-Response Optimization Approach

    SciTech Connect

    Datta, Saurav; Biswas, Ajay; Bhaumik, Swapan; Majumdar, Gautam

    2011-01-17

    Multi-objective optimization problem has been solved in order to estimate an optimal process environment consisting of optimal parametric combination to achieve desired quality indicators (related to bead geometry) of submerged arc weld of mild steel. The quality indicators selected in the study were bead height, penetration depth, bead width and percentage dilution. Taguchi method followed by utility concept has been adopted to evaluate the optimal process condition achieving multiple objective requirements of the desired quality weld.

  1. An eye for vulgarity : how MoMA saw color through Wild Bill's lens

    E-print Network

    Kivlan, Anna Karrer

    2007-01-01

    This thesis is an examination of the 1976 Museum of Modern Art exhibition of color photographs by William Eggleston-the second one-man show of color photography in the museum's history- with particular attention to the ...

  2. The first time ever I saw your feet: inversion effect in newborns' sensitivity to biological motion.

    PubMed

    Bardi, Lara; Regolin, Lucia; Simion, Francesca

    2014-04-01

    Inversion effect in biological motion perception has been recently attributed to an innate sensitivity of the visual system to the gravity-dependent dynamic of the motion. However, the specific cues that determine the inversion effect in naïve subjects were never investigated. In the present study, we have assessed the contribution of the local gravity-dependent motion (i.e., the orientation of individual dot trajectories) and the global configuration (i.e., the vertical location of the dots representing the feet within the display) in determining the inversion effect for biological motion in humans at birth. Results showed that 2-day-old newborns, at their 1st exposure to point-light displays, preferred a biological motion stimulus representing the legs of a walking animal compared with an identical display in which individual dot trajectories were locally inverted so that the motion violates the gravity force (Experiment 1). Interestingly, the global configuration affected the analysis of the gravity-dependent profile of dots motion. Indeed, the spontaneous preference disappeared when the local dots representing feet were embedded in a more complex global display and all the dots representing feet were located on the ground below the rest of the body (Experiment 2). Finally, results revealed that the orientation of the global configuration per se is not a crucial factor in determining newborns' preference (Experiment 3). These results suggest that humans possess an inborn predisposition about the direction of the gravity force that imprints biological motion and supports the hypothesis that a mechanism for the detection of biological motion is already at work before visual experience. PMID:24099548

  3. Lepton parameters in the see-saw model extended by one extra Higgs doublet

    E-print Network

    Alejandro Ibarra; Ana Solaguren-Beascoa

    2014-09-17

    We investigate the radiative generation of lepton masses and mixing angles in the Standard Model extended by one right-handed neutrino and one extra Higgs doublet. We assume approximate rank-1 Yukawa couplings at a high energy scale and we calculate the one loop corrected charged lepton and neutrino mass matrices at the low energy scale. We find that quantum effects generate, for typical high energy parameters, a hierarchy between the muon and the tau mass, a hierarchy between the solar and the atmospheric mass splittings, and a pattern of leptonic mixing angles in qualitative agreement with experiments.

  4. saw a ball of excess chain segments at the relaxing end until about 100 s (25).

    E-print Network

    Perkins, Thomas

    AND NOTES 1. J. D. Ferry, Viscoelastic Properties of Polymers (Wiley, New York, ed. 3,1980). 2. P. G. de in this paper allow for direct observation and controlled deformation of single DNA molecules. Using optical by hybridization. 18. Earlier work on manipulation of DNA with optical tweezers was reported by S. Chu and S. Kron

  5. Polygons Cuttable by a Circular Saw Erik D. Demaine Martin L. Demaine Craig S. Kaplan y

    E-print Network

    Demaine, Erik

    be expensive even for straight cuts. For stained glass and ceramic tiles it is common to score the material is that the blades have teeth to cut #3; Department of Computer Science, University of Waterloo, Waterloo, Ontario N2

  6. I Saw It on TV. More Vocational Educators Use PSAs and Videos to Reach Potential Students.

    ERIC Educational Resources Information Center

    Maxwell, Bruce

    1994-01-01

    Discusses how a growing number of states and school districts are using public service announcements (PSAs) to recruit students. Describes how a world-class decathlete appeared for free in a PSA for the Idaho Division of Vocational Education. (JOW)

  7. "Hey, I Saw Your Grandparents at Walmart": Teacher Education for Rural Schools and Communities

    ERIC Educational Resources Information Center

    Eppley, Karen

    2015-01-01

    This is a case study about how teacher education might better prepare rural teacher candidates for rural schools. Parents, teachers, community members, and students associated with a rural school described what is important in the preparation of teachers for today's rural schools. Their goals and wishes for their children's school and…

  8. What the Butler Saw: Lee Daniels's Studies in Biography and History

    ERIC Educational Resources Information Center

    Beck, Bernard

    2014-01-01

    The movie "Lee Daniels' The Butler" is an example of a work that is meant not only to entertain but to convey an important attitude and offer important viewpoints. The movie deals with a deep issue in the history of movies and the history of the country: racial inequality. Three issues are discussed in this article: (a) African…

  9. SAW Assessment Report Offshore Hake725 D. OFFSHORE HAKE STOCK ASSESSMENT FOR 2010

    E-print Network

    to provide a reliable definition for overfished and overfishing for this stock. SEINE and AIM modeling of Reference 1. Use models to estimate the commercial catch. Describe the uncertainty in these sources of data of abundance, recruitment, age-length data, etc.). Describe the uncertainty in these sources of data. 3

  10. Animal Intelligence66 Scientific American Presents Iused to tell students that no one ever heard, saw,

    E-print Network

    Pylyshyn, Zenon

    Animal Intelligence66 Scientific American Presents Iused to tell students that no one ever heard other animals, including a variety of primates, elephants, birds and even dolphins, have been tested Intelligence 67Can Animals Empathize? Let me begin with a point on which Gordon Gallup, Jr., and I agree

  11. One GHz leaky SAW velocity of metal layers and bilayers evaporated onto fused quartz

    NASA Technical Reports Server (NTRS)

    Walikainen, Dale

    1992-01-01

    An acoustic microscope operating at 1 GHz was used to determine the surface acoustic wave velocities v of thin film metal layers and metal bilayers deposited onto fused quartz. V(0)'s influence was reduced by gating. This produced a calibrated accuracy of 3 percent. A program was constructed from the explicitly solved 6 x 6 theoretical determinant. Single film thicknesses were decided upon by using this theory to produce a v equal to a standard. Since the single film v's were linear with respect to their thickness, half the single film thicknesses were used for the bilayered films. The velocities for these bilayered films agreed with theory. This experimentally confirms the theoretical technique used here to examine bilayered systems, or a prototype composite interphase. No discrepancy was seen for gold films as others have reported. V(z) seemed insensitive to the formation of intermetallics or CuO. Some annealed and unannealed platinum films did not change the v from that of fused quartz. Two platinum films whose v's were in agreement with theory peeled off with the tape test.

  12. Ultra Wide Band SAW Resonator Composed of Grooved Cu Electrodes and its Application to Tunable Filters

    NASA Astrophysics Data System (ADS)

    Kadota, Michio; Kimura, Tetsuya; Ida, Yasuyuki

    A cognitive radio system, which is researched to use a limited frequency resource effectively, requires a tunable filter with a wide variable frequency range. A resonator with wide band is required to realize the tunable filter. It was reported that a resonator composed of a Cu-electrode/15°YX-LiNbO3 had wide bandwidth of 12%. This time, authors attempted to fabricate an one-port resonator composed of a grooved Cu-electrode/4°YX-LiNbO3. As the result, it had a wider bandwidth of 17% of 1.3 times than that on Cu electrode/4°YX-LiNbO3. This resonator was applied to a tunable filter, and as the results, the tunable filter having tunable range of 6.8% in center frequency was experimentally realized using a band pass filter type circuit, and those having tunable range of 9 to 12% theoretically using a ladder type circuit.

  13. SMALLTOOTH SAWFISHScienti c Name: Pristis pectinata Why Are They Called Saw sh?

    E-print Network

    Species Act. A species is considered endangered when it faces a high risk of becoming extinct in the near water is mixed with seawater. Endangered: An "endangered" species can be a plant or animal that exists as a result of human activity. Endangered Species Act: The U.S. Endangered Species Act (ESA) is a Federal law

  14. Old Saws and New Materials: A Consideration of Some Ethical Problems.

    ERIC Educational Resources Information Center

    Morse, John F.

    1968-01-01

    Reports of job-hopping, opportunism, grantsmanship, and wheeling-dealing, based on the availability of federal research funds, by university faculty has created much concern in governmental and educational circles about the ethical problems these activities pose for the academic profession. In 1963, the Office of Science and Technology(OST) and…

  15. They saw a movie: Long-term memory for an extended audiovisual narrative

    PubMed Central

    Furman, Orit; Dorfman, Nimrod; Hasson, Uri; Davachi, Lila; Dudai, Yadin

    2007-01-01

    We measured long-term memory for a narrative film. During the study session, participants watched a 27-min movie episode, without instructions to remember it. During the test session, administered at a delay ranging from 3 h to 9 mo after the study session, long-term memory for the movie was probed using a computerized questionnaire that assessed cued recall, recognition, and metamemory of movie events sampled ?20 sec apart. The performance of each group of participants was measured at a single time point only. The participants remembered many events in the movie even months after watching it. Analysis of performance, using multiple measures, indicates differences between recent (weeks) and remote (months) memory. While high-confidence recognition performance was a reliable index of memory throughout the measured time span, cued recall accuracy was higher for relatively recent information. Analysis of different content elements in the movie revealed differential memory performance profiles according to time since encoding. We also used the data to propose lower limits on the capacity of long-term memory. This experimental paradigm is useful not only for the analysis of behavioral performance that results from encoding episodes in a continuous real-life-like situation, but is also suitable for studying brain substrates and processes of real-life memory using functional brain imaging. PMID:17562897

  16. Quality Comparison of Saw and Roller Ginning Three Mid-South Cultivars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three cultivars; Fibermax 960 BR, Deltapine 147 RF, and Deltapine 164 B2RF; were grown normally at Stoneville, MS and spindle harvested during the 2008 crop year. The cottons were processed with the same precleaning: dryer at 250°F, cylinder cleaner, stick machine, dryer at 240°F, and cylinder clea...

  17. "I Saw it in a Different Light": International Learning Experiences in Baccalaureate Nursing Education.

    ERIC Educational Resources Information Center

    Walsh, Linda V.; DeJoseph, Jeanne

    2003-01-01

    Ten nursing students and two faculty mentors participated in an immersion experience in Guatemala. Themes from interviews included the experience of being "other," growth as a professional nurse, and expansion of world views. (Contains 16 references.) (SK)

  18. 'I Saw You Disappear with My Own Eyes': Hidden Transcripts of New York Black Isrealite Bricolage

    E-print Network

    Dorman, Jacob S.

    2007-08-01

    To date, scholars have tended to view Black Israelites as mercenary, derivative, or imitative. However, this microhistorical reading of the public, partial, and hidden transcripts of New York Rabbi Wentworth Arthur Matthew's ...

  19. Women Saw Large Decrease In Out-Of-Pocket Spending For Contraceptives After ACA Mandate Removed Cost Sharing.

    PubMed

    Becker, Nora V; Polsky, Daniel

    2015-07-01

    The Affordable Care Act mandates that private health insurance plans cover prescription contraceptives with no consumer cost sharing. The positive financial impact of this new provision on consumers who purchase contraceptives could be substantial, but it has not yet been estimated. Using a large administrative claims data set from a national insurer, we estimated out-of-pocket spending before and after the mandate. We found that mean and median per prescription out-of-pocket expenses have decreased for almost all reversible contraceptive methods on the market. The average percentages of out-of-pocket spending for oral contraceptive pill prescriptions and intrauterine device insertions by women using those methods both dropped by 20 percentage points after implementation of the ACA mandate. We estimated average out-of-pocket savings per contraceptive user to be $248 for the intrauterine device and $255 annually for the oral contraceptive pill. Our results suggest that the mandate has led to large reductions in total out-of-pocket spending on contraceptives and that these price changes are likely to be salient for women with private health insurance. PMID:26153316

  20. SASOL SciFest saw the start of a very productive science communication rally, where 8 FABI

    E-print Network

    " afforded the perfect opportunity for us to network and relax after a long day. SciFest had an extremely presented workshops daily as well as a featured evening lecture demonstrating the physics of music and his

  1. They Know I Saw It: Evaluation Apprehension and Diffusion of Responsibility in Bystander Reactions to a Violent Crime.

    ERIC Educational Resources Information Center

    Gottlieb, Avi; Schwartz, Shalom H.

    Male and female bystanders witnessed a violent theft in the course of a bogus "ESP Experiment." In addition to the subjects' sex, two experimental manipulations were orthogonally crossed. The subject was either the only one to witness the emergency, or witnessed it with an additional participant (diffusion of responsibility), and the subject's…

  2. Oviposition Site Preference and Factors InfluencingEgg Mass Characteristics of the Saw-Combed Fishfly (Megaloptera

    E-print Network

    Pennuto, Chris

    1986). The Corydalidaeare excellent model organisms to examine oviposition site selection because),commonly called hellgrammites or fisMies, are rather long-lived holometabolousinsects common in streams and ponds oviposition site would seem paramount to ensuring successfulcompletion of the life cycle. Recruitment via

  3. Analysis of chain saw lubricating oils commonly used in Thailand's southern border provinces for forensic science purpose.

    PubMed

    Choodum, Aree; Tripuwanard, Kijja; Daeid, Niamh Nic

    2014-08-01

    In recent years, Thailand's southern border provinces (Malay-Muslim-majority border provinces) have become the scene of violence and insurgency. One of the attack patterns is the blocking of roads with perennial plants followed by planned attacks using improvised explosive devices (IEDs) or weapons on first responders. Containers of viscous dark lubricating oil and traces of lubricants on the felled trees were usually found at the scene. These were suspected to be chain oil lubricant from the chainsaws used to cut down the trees used for the roadblock. This work aimed to differentiate the chromatographic patterns of used lubricating oils available in automobile repair shops from various locations across Thailand's southern border provinces. Lubricating oils were analyzed using gas chromatography/flame ionization detector (GC/FID) every two weeks to study their variation in chemical compositions over time. The results obtained from GC/FID were normalized for differentiation. This included four two-stroke, six four-stroke, and three recycled oils. Two lubricating oils found at an incident scene were also analyzed and the results compared with the chain oil from five seized chainsaws. PMID:24875837

  4. FEM simulation of Rayleigh waves for CMOS compatible SAW devices based on AlN/SiO?/Si(100).

    PubMed

    Kaletta, Udo Christian; Wenger, Christian

    2014-01-01

    A simulation study of Rayleigh wave devices based on a stacked AlN/SiO?/Si(100) device was carried out. Dispersion curves with respect to acoustic phase velocity, reflectivity and electromechanical coupling efficiency for tungsten W and aluminium Al electrodes and different layer thicknesses were quantified by 2D FEM COMSOL simulations. Simulated acoustic mode shapes are presented. The impact of these parameters on the observed Rayleigh wave modes was discussed. High coupling factors of 2% and high velocities up to 5000 m/s were obtained by optimizing the AlN/SiO? thickness ratio. PMID:23684473

  5. TGfU--Would You Know It if You Saw It? Benchmarks from the Tacit Knowledge of the Founders

    ERIC Educational Resources Information Center

    Butler, Joy

    2014-01-01

    This paper explores the tacit expert knowledge and understanding about games curriculum and pedagogy of three men, Len Almond, David Bunker, and Rod Thorpe, credited as the founders of the Teaching Games for Understanding (TGfU) model. The model emerged from teacher practice in the late 1970s and was little theorized at the time, apart from a…

  6. 75 FR 13543 - Decision To Evaluate a Petition To Designate a Class of Employees for the Simonds Saw and Steel...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-22

    ... Occupational Safety and Health (NIOSH), Department of Health and Human Services (HHS). ACTION: Notice. SUMMARY..., National Institute for Occupational Safety and Health (NIOSH), 4676 Columbia Parkway, MS C-46, Cincinnati....GOV . John Howard, Director, National Institute for Occupational Safety and Health. BILLING CODE......

  7. The First Time Ever I Saw Your Feet: Inversion Effect in Newborns' Sensitivity to Biological Motion

    ERIC Educational Resources Information Center

    Bardi, Lara; Regolin, Lucia; Simion, Francesca

    2014-01-01

    Inversion effect in biological motion perception has been recently attributed to an innate sensitivity of the visual system to the gravity-dependent dynamic of the motion. However, the specific cues that determine the inversion effect in naïve subjects were never investigated. In the present study, we have assessed the contribution of the local…

  8. Onset and decay of the 1+1 Hawking-Unruh effect: what the derivative-coupling detector saw

    E-print Network

    Benito A. Juárez-Aubry; Jorma Louko

    2014-11-25

    We study an Unruh-DeWitt particle detector that is coupled to the proper time derivative of a real scalar field in 1+1 spacetime dimensions. Working within first-order perturbation theory, we cast the transition probability into a regulator-free form, and we show that the transition rate remains well defined in the limit of sharp switching. The detector is insensitive to the infrared ambiguity when the field becomes massless, and we verify explicitly the regularity of the massless limit for a static detector in Minkowski half-space. We then consider a massless field for two scenarios of interest for the Hawking-Unruh effect: an inertial detector in Minkowski spacetime with an exponentially receding mirror, and an inertial detector in $(1+1)$-dimensional Schwarzschild spacetime, in the Hartle-Hawking-Israel and Unruh vacua. In the mirror spacetime the transition rate traces the onset of an energy flux from the mirror, with the expected Planckian late time asymptotics. In the Schwarzschild spacetime the transition rate of a detector that falls in from infinity gradually loses thermality, diverging near the singularity proportionally to $r^{-3/2}$.

  9. A see-saw of pre-Columbian boom regions in southern Peru, determined by large-scale circulation changes

    NASA Astrophysics Data System (ADS)

    Mächtle, B.; Schittek, K.; Forbriger, M.; Schäbitz, F.; Eitel, B.

    2012-04-01

    Environmental changes and cultural transitions during several periods of Peruvian history show a strong coincidence between humid and dry climatic oscillations and the rise and decline of cultures. It is noteworthy, that alternating periods of geo-ecological fragility and stability occurred in time and space between the coastal Nasca region (14.5° S) and the high Andean northern Titicaca basin, just a few hundred kilometers to the east. Based on a multi-proxy palynological and sedimentological approach to reconstruct palaeoenvironmental changes, we found that the Nasca region received a maximum of precipitation during the archaeological boom times of the Early Horizon and the Early Intermediate Period (800 BC - 650 AD, Paracas and Nasca cultures) as well as during the late intermediate period (1150-1450 AD), whereas, in contrast, the Titicaca region further to the south-east experienced drought and cultural depression during that times. During the Middle Horizon (650 - 1150 AD), the Tiwanaku agronomy and culture boomed in the Titicaca region and expanded to the west, contemporaneous with a raised lake level and more humid conditions. In the Nasca region, runoff for irrigation purposes was reduced and less reliable due to drought. Considering a coincidence between environmental and cultural changes, we state that success and decline of civilizations were controlled by hydrological oscillations, triggering fertility as well as a critical loss of natural resources. In response to spatial changing resources, cultural foci were shifted. Therefore, the success of pre-Columbian civilizations was closely coupled to areas of geo-ecological favorability, which were directly controlled by distinct regional impacts of large-scale circulation mechanisms, including El Niño - Southern Oscillation (ENSO). Changes in the position of the intertropical convergence zone (ITCZ) and the Bolivian anticyclone determined meridional shifts in moisture transport across the Andes, which directly triggered human migration to the respective granaries.

  10. APPLICATION 2: NOUN PHRASE COREFERENCE In Chapter 4, we saw how cop-kmeans performed much better than the reg-

    E-print Network

    Wagstaff, Kiri L.

    [the world]'s [first artificial Earth satellite], [Sputnik I], on [October 4], [1957]. Mars the Red Planet its that nation the Soviet Union Sputnik I first artificial Earth satellite Figure 5.1: An excerpt

  11. Optimization of the Depth of Penetration by Welding Input Parameters in SAW Process Using Response Surface Methodology

    NASA Astrophysics Data System (ADS)

    Kazemi, Mohsen; Aghakhani, Masood; Haghshenas-Jazi, Ehsan; Behmaneshfar, Ali

    2015-11-01

    The aim of this paper is to optimize the depth of penetration with regard to the effect of MgO nanoparticles and welding input parameters. For this purpose, response surface methodology (RSM) with central composite rotatable design (CCRD) was used. The welding current, arc voltage, nozzle-to-plate distance, welding speed, and thickness of MgO nanoparticles were determined as the factors, and depth of penetration was considered as the response. Quadratic polynomial model was used for determining the relationship between the response and factors. A reduced model was obtained from the data which the values of R 2, R 2 (pred), and R 2 (adj) of this model were 92.05, 69.05, and 86.31 pct, respectively. Thus, this model was suitable, and it was used to determine the optimum levels of factors. The results show that the welding current, arc voltage, and nozzle-to-plate distance factors should be adjusted in high level, and welding speed and thickness of MgO nanoparticles factors should be adjusted in low level.

  12. "Such a smoking nation as this I never saw...": smoking, nationalism, and manliness in nineteenth-century Hungary.

    PubMed

    Maxwell, Alexander

    2006-01-01

    Tobacco smoking became an important marker of Hungarian national identity during the nineteenth century. this national symbol ultimately had an economic origin: Hungarian tobacco producers resisted the tobacco monopoly of the Habsburg central government, and led an ultimately successful consumer boycott of Austrian products. Tobacco nationalism, however, became a common theme in Hungarian popular culture in its own right, as tobacco use came to symbolize community and fraternity. The use of tobacco was also highly gendered; smoking as a metaphor for membership shows that the Hungarian nation was a gender-exclusive "national brotherhood." PMID:20058399

  13. Envenomation by Echis coloratus (Mid-East saw-scaled viper): a review of the literature and indications for treatment.

    PubMed

    Benbassat, J; Shalev, O

    1993-04-01

    Envenomation by the snake Echis coloratus causes a local swelling and hemostatic failure. Most cases recover uneventfully, however about one-third of the victims bleed or develop anemia, and one known death due to renal failure has been reported. Uncontrolled observations suggest that treatment by a specific antivenom reduces the duration of the hemostatic failure. Still the management of victims of E coloratus remains uncertain. Some authors advocate antivenom treatment for all patients, while others recommend its use only in the event of complications. We review reported data on the effect of the venom in vitro, in laboratory animals and in humans, and reexamine alternative treatment strategies by applying a revised version of a published decision model. The probability of bleeding and the efficacy of antivenom treatment were the main determinants in the choice between antivenom treatment and expectant management of victims of E. coloratus. Assuming a therapeutic efficacy of 32%, the decision model favored antivenom treatment when the risk of bleeding exceeded 7.5%. The estimated risk of bleeding exceeds this threshold in patients who present with either proteinuria, a blood urea of > 7 mmol/l, a platelet count of < 100,000/microliters, or a hemoglobin level of < 13 g/dl. In patients who had been exposed to antiserum in the past, or in whom the annual probability of future envenomation exceeds 0.9%, antivenom treatment was preferred only when bleeding was certain. Errors in our estimates of the efficacy of antivenom treatment, of the mortality after a bleeding event and of the risk of anaphylaxis after a repeated exposure to antiserum may have affected our conclusions. Nonetheless, they are consistent with presently available information and, pending more reliable estimates, may be considered as guidelines for treatment. PMID:8491579

  14. Onset and decay of the 1 + 1 Hawking-Unruh effect: what the derivative-coupling detector saw

    NASA Astrophysics Data System (ADS)

    Juárez-Aubry, Benito A.; Louko, Jorma

    2014-12-01

    We study an Unruh-DeWitt particle detector that is coupled to the proper time derivative of a real scalar field in 1 + 1 spacetime dimensions. Working within first-order perturbation theory, we cast the transition probability into a regulator-free form, and we show that the transition rate remains well defined in the limit of sharp switching. The detector is insensitive to the infrared ambiguity when the field becomes massless, and we verify explicitly the regularity of the massless limit for a static detector in Minkowski half-space. We then consider a massless field for two scenarios of interest for the Hawking-Unruh effect: an inertial detector in Minkowski spacetime with an exponentially receding mirror, and an inertial detector in (1+1)-dimensional Schwarzschild spacetime, in the Hartle-Hawking-Israel and Unruh vacua. In the mirror spacetime the transition rate traces the onset of an energy flux from the mirror, with the expected Planckian late time asymptotics. In the Schwarzschild spacetime the transition rate of a detector that falls in from infinity gradually loses thermality, diverging near the singularity proportionally to {{r}-3/2}.

  15. Hybrid method for the precise calculation of the general dyadic Greens functions for SAW and leaky wave substrates.

    SciTech Connect

    Branch, Darren W.

    2008-05-01

    Recently, the generalized method for calculation of the 16-element Green's function for analysis of surface acoustic waves has proven crucial to develop more sophisticated transducers. The generalized Green's function provides a precise relationship between the acoustic stresses and electric displacement on the three mechanical displacements and electric potential. This generalized method is able to account for mass loading effects which is absent in the effective permittivity approach. However, the calculation is numerically intensive and may lead to numerical instabilities when solving for both the eigenvalues and eigenvectors simultaneously. In this work, the general eigenvalue problem was modified to eliminate the numerical instabilities in the solving procedure. An algorithm is also presented to select the proper eigenvalues rapidly to facilitate analysis for all types of acoustic propagation. The 4 x 4 Green's functions and effective permittivities were calculated for materials supporting Rayleigh, leaky, and leaky longitudinal waves as demonstration of the method.

  16. Balancing the See-Saw: A Kaleidoscopic Paradigm Shift of Know-How (21st Century Education and Training Priorities).

    ERIC Educational Resources Information Center

    Lenaghan, Donna D.

    The information and service industries are and will remain the largest areas of growth/employment. Among current/projected changes in the work environment are the following: greater competition within/beyond the continental borders of the United States; increasing reliance on new equipment/processes; more/constantly changing information to be…

  17. Real-time monitoring of calcium carbonate and cationic peptide deposition on carboxylate-SAM using a microfluidic SAW biosensor

    PubMed Central

    Pohl, Anna

    2014-01-01

    Summary A microfluidic biosensor with surface acoustic wave technology was used in this study to monitor the interaction of calcium carbonate with standard carboxylate self-assembled monolayer sensor chips. Different fluids, with and without biomolecular components, were investigated. The pH-dependent surface interactions of two bio-inspired cationic peptides, AS8 and ES9, which are similar to an extracellular domain of the chitin synthase involved in mollusc shell formation, were also investigated in a biological buffer system. A range of experimental conditions are described that are suitable to study non-covalent molecular interactions in the presence of ionic substances, such as, mineral precursors below the solubility equilibrium. The peptide ES9, equal to the mollusc chitin synthase epitope, is less sensitive to changes in pH than its counterpart AS8 with a penta-lysine core, which lacks the flanking acidic residues. This study demonstrates the extraordinary potential of microfluidic surface acoustic wave biosensors to significantly expand our experimental capabilities for studying the principles underlying biomineralization in vitro. PMID:25383294

  18. The dna 󪩧saw puzzle??ructure model: the case studies of the rice and yeast genomes 

    E-print Network

    Liu, Yun-Hua

    2009-05-15

    , it is unknown whether this model is held in other species. Here we report the studies of the DNA structure model using the monocot plant model species, rice (Oryza sativa), and the single-celled model species, yeast (Saccharomyces cerevisiae). Analyses...

  19. Interfacing low-energy SAW nebulization with Liquid Chromatography-Mass Spectrometry for the analysis of biological samples

    PubMed Central

    Tveen-Jensen, Karina; Gesellchen, Frank; Wilson, Rab; Spickett, Corinne M.; Cooper, Jonathan M.; Pitt, Andrew R.

    2015-01-01

    Soft ionization methods for the introduction of labile biomolecules into a mass spectrometer are of fundamental importance to biomolecular analysis. Previously, electrospray ionization (ESI) and matrix assisted laser desorption-ionization (MALDI) have been the main ionization methods used. Surface acoustic wave nebulization (SAWN) is a new technique that has been demonstrated to deposit less energy into ions upon ion formation and transfer for detection than other methods for sample introduction into a mass spectrometer (MS). Here we report the optimization and use of SAWN as a nebulization technique for the introduction of samples from a low flow of liquid, and the interfacing of SAWN with liquid chromatographic separation (LC) for the analysis of a protein digest. This demonstrates that SAWN can be a viable, low-energy alternative to ESI for the LC-MS analysis of proteomic samples. PMID:25978651

  20. The Twentieth century saw fundamental shifts in northern Eurasian political and land-management paradigms, in Russia

    E-print Network

    Brown, Daniel G.

    in primarily forested study sites. Landsat resolved conifer, mixed, deciduous and young forest; cuts, burns during the 1974 to 1990 time period. Deciduous forest increased over both time periods. Agriculture of forest area in the three study sites was likely disturbed prior to 1974. Conifer forest decreased over

  1. Jitter-Tolerance and Blocker-Tolerance of Delta-Sigma Analog-to-Digital Converters for Saw-Less Multi-Standard Receivers 

    E-print Network

    Ahmed, Ramy 1981-

    2012-12-05

    The quest for multi-standard and software-defined radio (SDR) receivers calls for high flexibility in the receiver building-blocks so that to accommodate several wireless services using a single receiver chain in mobile ...

  2. The London Hospital 1984 Graduates 30 year reunion Saturday October 4th 2014 saw the gathering back in the East End of around ninety medics

    E-print Network

    Chittka, Lars

    it was a great success. People travelled from far and wide including Australia, North America and Chile. Lewis has very kindly uploaded the images to a Google drive at https://sites.google.com/site/lhmc30 to make the evening such a great and enjoyable success ­ here's to our 35th reunion party! (the above

  3. A review of the bipolar see-saw from synchronized and high resolution ice core water stable isotope records from Greenland and East Antarctica

    NASA Astrophysics Data System (ADS)

    Landais, A.; Masson-Delmotte, V.; Stenni, B.; Selmo, E.; Roche, D. M.; Jouzel, J.; Lambert, F.; Guillevic, M.; Bazin, L.; Arzel, O.; Vinther, B.; Gkinis, V.; Popp, T.

    2015-04-01

    Numerous ice core records are now available that cover the Last Glacial cycle both in Greenland and in Antarctica. Recent developments in coherent ice core chronologies now enable us to depict with a precision of a few centuries the relationship between climate records in Greenland and Antarctica over the millennial scale variability of the Last Glacial period. Stacks of Greenland and Antarctic water isotopic records nicely illustrate a seesaw pattern with the abrupt warming in Greenland being concomitant with the beginning of the cooling in Antarctica at the Antarctic Isotopic Maximum (AIM). In addition, from the precise estimate of chronological error bars and additional high resolution measurements performed on the EDC and TALDICE ice cores, we show that the seesaw pattern does not explain the regional variability in Antarctic records with clear two step structures occurring during the warming phase of AIM 8 and 12. Our Antarctic high resolution data also suggest possible teleconnections between changes in low latitude atmospheric circulation and Antarctic without any Greenland temperature fingerprint.

  4. ESRP 285 Climate Chart Questions: Your Name _______________________________ You saw Figure 1 in class. It shows estimates of atmospheric CO2 in black, average earth

    E-print Network

    Ford, Andrew

    in class. It shows estimates of atmospheric CO2 in black, average earth temperature in red and sea level be much higher than normal every 100,000 yrs #12;5. Figure 1 shows the average earth temperature

  5. Full lineup serves wide variety of processing needs DAD3220, 3230 or 3430 is a one-axis dicing saw for 6-inch (6-inch square)

    E-print Network

    device data, helps prevent operator error while supporting a stable and consistent flow of cutting water % smaller footprint DAD3220 W500 x 900 mm 0.45 m2 900mm 1,050mm 500 mm DAD3220/3230/3430 Specifications DAD. comsuption L/min(ANR) 170 200 Cutting water, Cleaning water Water pressure MPa 0.2 - 0.4 Max. consumption

  6. "We Actually Saw Atoms with Our Own Eyes": Conceptions and Convictions in Using the Scanning Tunneling Microscope in Junior High School

    ERIC Educational Resources Information Center

    Margel, Hannah; Eylon, Bat-Sheva; Scherz, Zahava

    2004-01-01

    The feasibility and the potential contribution of the scanning tunneling microscopy (STM) in junior high school (JHS) as an instructional tool for learning the particulate nature of matter is described. The use and power of new technologies can probably be demonstrated by the scanning tunneling microscopy (STM).

  7. that could be `cured' by lifelong oestrogen replacement. The first period saw older women through societies' `maternalist ideology'. Women were mothers, and when their reproductive

    E-print Network

    Merchant, Carolyn

    and anxiety, as feminine superstition, gossip and too much idle time for bridge produced a psychological Wilson, others praised him because he motivated women to retain control of their bodies and helped the rumblings of enormous change that affected different women in different ways. Houck even speculates

  8. In situ atomic force microscopy of laser-conditioned and laser- damaged HfO sub 2 /saw sub 2 dielectric mirror coatings

    SciTech Connect

    Staggs, M.C.; Balooch, M.; Kozlowski, M.R.; Siekhaus, W.J.

    1991-01-07

    Atomic force microscopy was used to determine in situ the nm-scale morphological changes that occur on dielectric optical coatings as a result of laser illumination. Of particular interest is a process called laser conditioning in which the damage threshold of the films is increased by a factor of 2 to 3 when the film is first illuminated at fluences below the damage threshold. The optical coating studied was a highly reflective dielectric multilayer mirror (HR) consisting of many alternating quarter-wave layers of HfO{sub 2} and SiO{sub 2} at 1.06 {mu}m. The top layer was a {lambda}/2 SiO{sub 2} overcoat. Laser beam specifications were: 1.06-{mu}m wavelength, 8- to 10-ns pulsewidth. Laser beam spot sizes ranging from 85 {mu}m to 1.4 mm in diameter. The maximum scan range of the AFM was 80 {mu}m. A survey of the as-deposited surface shows mostly hillocks approximately 200 nm in diameter and 10 nm in height. The predominant surface irregularity is {mu}m-scale domes associated with well known nodule defects. Laser illumination causes nodule defects to be easily ejected from the coating surface. Further damage may propagate from the resulting craters. These nodule defects therefore determine the damage threshold of the film. Using the AFM we have shown that for illumination at fluences below the nodule ejection threshold we observe a decrease in the surface roughness of the nodule defects and hillock structure of the as-deposited film. The subtle changes in these surface features may be an indication that the film is being mechanically stabilized, thus providing the observed conditioning effect.

  9. In situ atomic force microscopy of laser-conditioned and laser- damaged HfO{sub 2}/saw{sub 2} dielectric mirror coatings

    SciTech Connect

    Staggs, M.C.; Balooch, M.; Kozlowski, M.R.; Siekhaus, W.J.

    1991-01-07

    Atomic force microscopy was used to determine in situ the nm-scale morphological changes that occur on dielectric optical coatings as a result of laser illumination. Of particular interest is a process called laser conditioning in which the damage threshold of the films is increased by a factor of 2 to 3 when the film is first illuminated at fluences below the damage threshold. The optical coating studied was a highly reflective dielectric multilayer mirror (HR) consisting of many alternating quarter-wave layers of HfO{sub 2} and SiO{sub 2} at 1.06 {mu}m. The top layer was a {lambda}/2 SiO{sub 2} overcoat. Laser beam specifications were: 1.06-{mu}m wavelength, 8- to 10-ns pulsewidth. Laser beam spot sizes ranging from 85 {mu}m to 1.4 mm in diameter. The maximum scan range of the AFM was 80 {mu}m. A survey of the as-deposited surface shows mostly hillocks approximately 200 nm in diameter and 10 nm in height. The predominant surface irregularity is {mu}m-scale domes associated with well known nodule defects. Laser illumination causes nodule defects to be easily ejected from the coating surface. Further damage may propagate from the resulting craters. These nodule defects therefore determine the damage threshold of the film. Using the AFM we have shown that for illumination at fluences below the nodule ejection threshold we observe a decrease in the surface roughness of the nodule defects and hillock structure of the as-deposited film. The subtle changes in these surface features may be an indication that the film is being mechanically stabilized, thus providing the observed conditioning effect.

  10. Tveen-Jensen, K., Gesellchen, F., Wilson, R., Spickett, C. M., Cooper, J. M., and Pitt, A. R. (2015) Interfacing low-energy SAW nebulization with

    E-print Network

    2015-01-01

    with liquid chromatographic separation (LC) for the analysis of a protein digest. This demonstrates that SAWN) currently form the cornerstones of mass spectrometric analysis of proteins, peptides and polar metabolites oxidation in samples, even under conditions where no visible corona discharge occurs8 , and there is still

  11. 77 FR 38173 - Child Labor Regulations, Orders and Statements of Interpretation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-27

    ...Occupations involving the operation of circular saws, band saws, guillotine shears, chain saws, reciprocating saws, wood chippers, and abrasive cutting discs (Order 14). [FR Doc. 2012-15868 Filed 6-26-12; 8:45 am] BILLING CODE...

  12. 29 CFR 1910.213 - Woodworking machinery requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... be so constructed that they can be firmly secured to the table or table assembly without changing... (other than self-feed saws with a roller or wheel at back of the saw) shall be provided with a spreader... thicker than the saw disk. (f) Self-feed circular saws. (1) Feed rolls and saws shall be protected by...

  13. 3. Photocopied August 1975 from The Evolution of Modern Band ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Photocopied August 1975 from The Evolution of Modern Band Saw Mills for Sawing Logs, Dewitt Clinton Prescott, 1910. VIEW OF BAND SAW. *NOTE* 4'x 5' NEGATIVE - Meadow River Lumber Company, Highway 60, Rainelle, Greenbrier County, WV

  14. Variable depth core sampler

    DOEpatents

    Bourgeois, P.M.; Reger, R.J.

    1996-02-20

    A variable depth core sampler apparatus is described comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member. 7 figs.

  15. Variable depth core sampler

    DOEpatents

    Bourgeois, Peter M. (Hamburg, NY); Reger, Robert J. (Grand Island, NY)

    1996-01-01

    A variable depth core sampler apparatus comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member.

  16. On December 26, 2004 the world saw yet again how strains built up over hundreds of years by slow and almost imperceptible motions of tectonic plates are released with devastating effect. A

    E-print Network

    Stein, Seth

    on a seismogram. The earli- est magnitude scale, introduced by Charles Richter in 1935 for Southern California earth- quakes, is the local or "Richter" magnitude. This scale has been replaced by other magni- tude scales that

  17. About the Issue: Elective Delivery Prior to 39 Weeks of Gestation Between 1990 and 2006, the United States saw a 50% increase in deliveries at 37 to 38 weeks of

    E-print Network

    Rau, Don C.

    , allowing the baby to remain in the womb at least 39 weeks is safest for both baby and mother. Non-medically indicated deliveries between 37 and 39 weeks of gestation pose increased health risks for both mother consequences. If mother and baby are healthy, wait to deliver until at least 39 weeks of gestation. Critical

  18. 29 CFR 1910.213 - Woodworking machinery requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) Bearings shall be kept free from lost motion and shall be well lubricated. (4) Arbors of all circular saws..., so as to avoid overspeed caused by mounting a saw larger than intended. (6) Circular saw fences shall... table. (7) Circular saw gages shall be so constructed as to slide in grooves or tracks that...

  19. 29 CFR 1910.213 - Woodworking machinery requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) Bearings shall be kept free from lost motion and shall be well lubricated. (4) Arbors of all circular saws..., so as to avoid overspeed caused by mounting a saw larger than intended. (6) Circular saw fences shall... table. (7) Circular saw gages shall be so constructed as to slide in grooves or tracks that...

  20. X-ray imaging and diffraction from surface phonons on GaAs W. Sauer,a)

    E-print Network

    Ludwig-Maximilians-Universität, München

    -gap semiconductor, GaAs is a very promising material for further SAW applications,9 as well as a material for a SAW-tunable Grenoble, France Received 3 March 1999; accepted for publication 21 July 1999 Surface acoustic waves SAWs-ray diffraction techniques. Using stroboscopic topography, the SAW emission of a parallel and a focusing

  1. Friction measurement on a glass substrate using surface acoustic wave

    NASA Astrophysics Data System (ADS)

    Kotani, Hiroyuki; Takasaki, Masaya; Mizuno, Takeshi

    2010-01-01

    A method to provide human tactile sensation using surface acoustic wave (SAW) was proposed. A stator transducer material (piezoelectric material) of a SAW tactile display, however, had constraint of size and shape. Previously, to solve this problem, a new method was proposed to excite and propagate SAW on a non-piezoelectric material surface. Excitation and propagation of SAW on a non-piezoelectric material is realized by combination of a LiNbO3 plate and a glass substrate. Using the method, the glass substrate SAW tactile display could realize tactile sensation in the same manner as the conventional SAW tactile display. However, a relationship between the friction coefficient and vibration amplitude is unclear in the glass substrate SAW tactile display. To decide and optimize the control parameters of the glass substrate SAW tactile display, the relation is needed. In this research, the friction shifts was experimentally confirmed in the glass substrate SAW tactile display. Additionally, the relation was investigated.

  2. Microfluidic pumping through miniaturized channels driven by ultra-high frequency surface acoustic waves

    SciTech Connect

    Shilton, Richie J.; Travagliati, Marco; Beltram, Fabio; Cecchini, Marco

    2014-08-18

    Surface acoustic waves (SAWs) are an effective means to pump fluids through microchannel arrays within fully portable systems. The SAW-driven acoustic counterflow pumping process relies on a cascade phenomenon consisting of SAW transmission through the microchannel, SAW-driven fluid atomization, and subsequent coalescence. Here, we investigate miniaturization of device design, and study both SAW transmission through microchannels and the onset of SAW-driven atomization up to the ultra-high-frequency regime. Within the frequency range from 47.8 MHz to 754?MHz, we show that the acoustic power required to initiate SAW atomization remains constant, while transmission through microchannels is most effective when the channel widths w???10??, where ? is the SAW wavelength. By exploiting the enhanced SAW transmission through narrower channels at ultra-high frequencies, we discuss the relevant frequency-dependent length scales and demonstrate the scaling down of internal flow patterns and discuss their impact on device miniaturization strategies.

  3. 4. Photocopied August 1975 from The Evolution of Modern Band ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Photocopied August 1975 from The Evolution of Modern Band Saw Mills for Sawing Logs, Dewitt Clinton Prescott, 1910. THREE-BLOCK LOG CARRIAGE. *NOTE* 4'x 5' NEGATIVE - Meadow River Lumber Company, Highway 60, Rainelle, Greenbrier County, WV

  4. Proceedings of the Low-Cost Solar Array Wafering Workshop

    NASA Technical Reports Server (NTRS)

    Morrison, A. D.

    1982-01-01

    The technology and economics of silicon ingot wafering for low cost solar arrays were discussed. Fixed and free abrasive sawing wire, ID, and multiblade sawing, materials, mechanisms, characterization, and innovative concepts were considered.

  5. Columbia University is in the heart of New York City, and for many students, the

    E-print Network

    Rubenstein, Dustin R.

    of the invasive prickly pear cactus, drongo foraging behavior, and optimal foraging in harvester ants. Although morning, we saw four female lions eating a warthog. And the following night, we saw a leopard and two

  6. 7. INTERIOR VIEW, PATTERN MAKING WORK BENCH AREA WEST WALL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. INTERIOR VIEW, PATTERN MAKING WORK BENCH AREA WEST WALL LOOKING WEST LATHE ON LEFT DELTA BAND SAW LEFT, DELTA 6' JOINTS AND DELTA TABLE SAW ON RIGHT. - Knight Foundry, 13 Eureka Street, Sutter Creek, Amador County, CA

  7. 40 CFR 471.104 - Pretreatment standards for existing sources (PSES).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...values: (a) Metal powder production atomization wastewater...01 (b) Sizing spent emulsions. Subpart J—PSES Pollutant...Sawing or grinding spent emulsions. Subpart J—PSES Pollutant...parts sawed or ground with emulsions Copper 0.035...

  8. 40 CFR 471.101 - Effluent limitations representing the degree of effluent reduction attainable by the application...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...BPT): (a) Metal powder production atomization wastewater...times. (b) Sizing spent emulsion. Subpart J—BPT Pollutant...Sawing or grinding spent emulsion. Subpart J—BPT Pollutant...parts sawed or ground with emulsion Copper 0.035...

  9. 40 CFR 471.105 - Pretreatment standards for new sources (PSNS).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...values: (a) Metal powder production atomization wastewater...01 (b) Sizing spent emulsions. Subpart J—PSNS Pollutant...Sawing or grinding spent emulsions. Subpart J—PSNS Pollutant...parts sawed or ground with emulsions Copper 0.035...

  10. 40 CFR 471.101 - Effluent limitations representing the degree of effluent reduction attainable by the application...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...BPT): (a) Metal powder production atomization wastewater...times. (b) Sizing spent emulsion. Subpart J—BPT Pollutant...Sawing or grinding spent emulsion. Subpart J—BPT Pollutant...parts sawed or ground with emulsion Copper 0.035...

  11. 40 CFR 471.105 - Pretreatment standards for new sources (PSNS).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...values: (a) Metal powder production atomization wastewater...01 (b) Sizing spent emulsions. Subpart J—PSNS Pollutant...Sawing or grinding spent emulsions. Subpart J—PSNS Pollutant...parts sawed or ground with emulsions Copper 0.035...

  12. 40 CFR 471.104 - Pretreatment standards for existing sources (PSES).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...values: (a) Metal powder production atomization wastewater...01 (b) Sizing spent emulsions. Subpart J—PSES Pollutant...Sawing or grinding spent emulsions. Subpart J—PSES Pollutant...parts sawed or ground with emulsions Copper 0.035...

  13. Carbon Monoxide Hazards from Small Gasoline Powered Engines

    MedlinePLUS

    ... gasoline-powered tools such as high-pressure washers, concrete cutting saws (walk-behind/hand-held), power trowels, ... parking garage. A plumber used a gasoline-powered concrete saw in a basement with open doors and ...

  14. 27 CFR 555.208 - Construction of type 2 magazines.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... prevent sawing or lever action on the locks, hasps, and staples. These requirements do not apply to... constructed so as to prevent sawing or lever action on the locks, hasps, and staples. Indoor magazines...

  15. 27 CFR 555.210 - Construction of type 4 magazines.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... steel hoods constructed so as to prevent sawing or lever action on the locks, hasps, and staples. These... constructed so as to prevent sawing or lever action on the locks, hasps, and staples. Indoor magazines...

  16. 27 CFR 555.210 - Construction of type 4 magazines.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... steel hoods constructed so as to prevent sawing or lever action on the locks, hasps, and staples. These... constructed so as to prevent sawing or lever action on the locks, hasps, and staples. Indoor magazines...

  17. 27 CFR 555.208 - Construction of type 2 magazines.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... prevent sawing or lever action on the locks, hasps, and staples. These requirements do not apply to... constructed so as to prevent sawing or lever action on the locks, hasps, and staples. Indoor magazines...

  18. RAQUEL FERNANDEZ, JONATHAN GINZBURG, HOWARD GREGORY AND SHALOM LAPPIN

    E-print Network

    Lappin, Shalom

    is the resolution of fragments. Basic examples include bare NP an- swers (1a), where the bare NP John is resolved as the assertion John saw Mary, and sluicing (1b), where the wh-phrase who is interpreted as the question Which student saw John. (1) a. A: Who saw Mary? B: John b. A: A student saw John. B: Who? Either the antecedent

  19. Machining of Silicon-Ribbon-Forming Dies

    NASA Technical Reports Server (NTRS)

    Menna, A. A.

    1985-01-01

    Carbon extension for dies used in forming silicon ribbon crystals machined precisely with help of special tool. Die extension has edges beveled toward narrow flats at top, with slot precisely oriented and centered between flats and bevels. Cutting tool assembled from standard angle cutter and circular saw or saws. Angle cutters cuts bevels while slot saw cuts slot between them. In alternative version, custom-ground edges or additional circular saws also cut flats simultaneously.

  20. Air-bar cotton lint cleaner

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Saw-type lint cleaners are now the most common lint cleaners used at gins because of their higher cleaning efficiency. Saw-type lint cleaning improves the grade of the fiber and increases the market value for the farmer. However, during the cleaning process the saw-type lint cleaners damage fiber in...

  1. Influence of grid bar shape on field cleaner performance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous research has shown that the performance of sling-off type cleaning machines designed to remove foreign matter from harvested seed cotton is influenced by design factors such as grid bar to saw cylinder clearance, grid bar spacing, saw cylinder speeds, and saw cylinder arrangement. However, ...

  2. Single-chip fused hybrids for acousto-electric and acousto-optic applications

    E-print Network

    Ludwig-Maximilians-Universität, München

    Single-chip fused hybrids for acousto-electric and acousto-optic applications M. Rotter,a) C. Rocke,2 The use of surface acoustic wave SAW filters and delay lines has had a strong impact on both the dynamical conductivity ,k was probed by SAW transmission experiments. Also, SAW in- duced lateral

  3. Visualization of Protocols of the Parsing and Semantic Interpretation Steps in a Machine Translation System

    E-print Network

    for the string saw the ape with his binoculars in Figure 2 illustrates. The processes of parsing and semantic associated with it. This feature 83 #12;dominance V, V' PP V NP with his binoculars sa~w the ,ape V ~ N P precedence the ape with his binoculars Parse Sequence (simplified) Step h V --saw Step 2: NP ~ the ape Step 3

  4. A rate analysis of binominal each Linmin Zhang, NYU // 2013 MACSIM

    E-print Network

    Pylkkänen, Liina

    is the counting quantifier requirement (see Szabolcsi 2010, Ch.8.4). (1a) The boys saw {one / three / *the / *a / *every / *- / *no / *cute} monkey(s) each. (1b) The boys each saw {one / three / the / a / every analysis of a binominal each sentence: The boys saw 3 monkeys each. 1 #12;LF: [(ix) [(viii) the boys [(vii

  5. 40 CFR 471.75 - Pretreatment standards for new sources (PSNS).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Molybdenum 0.018 0.008 (h) Sawing or grinding spent emulsions. Subpart...Molybdenum 0.029 0.013 (i) Sawing or grinding contact cooling water. ...Molybdenum 0.830 0.368 (j) Sawing or grinding rinse. Subpart...

  6. 40 CFR 471.73 - New source performance standards (NSPS).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...7.5 to 10.0 at all times. (h) Sawing or grinding spent emulsions. Subpart...7.5 to 10.0 at all times. (i) Sawing or grinding contact cooling water. ...7.5 to 10.0 at all times. (j) Sawing or grinding rinse. Subpart...

  7. UNCORRECTEDPROOF 3 A delay differential equation model for surface acoustic wave sensors

    E-print Network

    Chicone, Carmen

    equation model for surface acoustic wave (SAW) devices. Closed-loop SAW delay line 13 oscillators generator and the receptor. The frequency relationship is applied to a tunable SAWoscillator to provide. Introduction 23 A surface acoustic wave (SAW) is an elastic wave, a 24 Rayleigh wave [1], whose wave

  8. THE DEPARTMENT OF ELECTRICAL ENGINEERING AND COMPUTER SCIENCE, ECE DIVISION Presents the Spring 2013 EECS Seminar Series

    E-print Network

    DeMara, Ronald F.

    ) components. SAW filters are expensive and bulky and since they are not tunable, in mul band applica ons one) of onchip inductors, the outofband filtering is tradi onally a ained by offchip Sur face Acous c Wave (SAW systems, replacing SAW filters by onchip counterparts has become the longpursued goal among circuit

  9. High-Q Micromachined Silver Passives and Filters Mina Rais-Zadeh 1

    E-print Network

    Ayazi, Farrokh

    ) tunable and fixed passives, and low insertion loss bandpass LC filters. A combination of low-chip, acoustic-resonant components, such as SAW devices. While SAW filters offer very low insertion loss (IL) and high quality factor (Q), they cannot be tuned, and therefore many transmit and receive SAW filters

  10. Modeling of a Surface Acoustic Wave Strain Sensor

    NASA Technical Reports Server (NTRS)

    Wilson, W. C.; Atkinson, Gary M.

    2010-01-01

    NASA Langley Research Center is investigating Surface Acoustic Wave (SAW) sensor technology for harsh environments aimed at aerospace applications. To aid in development of sensors a model of a SAW strain sensor has been developed. The new model extends the modified matrix method to include the response of Orthogonal Frequency Coded (OFC) reflectors and the response of SAW devices to strain. These results show that the model accurately captures the strain response of a SAW sensor on a Langasite substrate. The results of the model of a SAW Strain Sensor on Langasite are presented

  11. Enhancement of acoustic streaming induced flow on a focused surface acoustic wave device: Implications for biosensing and microfluidics

    NASA Astrophysics Data System (ADS)

    Singh, Reetu; Sankaranarayanan, Subramanian K. R. S.; Bhethanabotla, Venkat R.

    2010-01-01

    Fluid motion induced on the surface of 100 MHz focused surface acoustic wave (F-SAW) devices with concentric interdigital transducers (IDTs) based on Y-cut Z-propagating LiNbO3 substrate was investigated using three-dimensional bidirectionally coupled finite element fluid-structure interaction models. Acoustic streaming velocity fields and induced forces for the F-SAW device are compared with those for a SAW device with uniform IDTs (conventional SAW). Both, qualitative and quantitative differences in the simulation derived functional parameters, such as device displacements amplitudes, fluid velocity, and streaming forces, are observed between the F-SAW and conventional SAW device. While the conventional SAW shows maximum fluid recirculation near input IDTs, the region of maximum recirculation is concentrated near the focal point of the F-SAW device. Our simulation results also indicate acoustic energy focusing by the F-SAW device leading to maximized device surface displacements, fluid velocity, and streaming forces near the focal point located in the center of the delay path, in contrast to the conventional SAW exhibiting maximized values of these parameters near the input IDTs. Significant enhancement in acoustic streaming is observed in the F-SAW device when compared to the conventional ones; the increase in streaming velocities was computed to be 352% and 216% for tangential velocities in propagation and transverse directions, respectively, and 353% for the normal velocity. Consequently, the induced streaming force for F-SAW is 480% larger than that for conventional SAW. In biosensing applications, this allows for the removal of smaller submicron sized particles by F-SAW which are otherwise difficult to remove using the conventional SAW. The F-SAW presents an order of magnitude reduction in the smallest removable particle size compared to the conventional device. Our results indicate that the acoustic energy focusing and streaming enhancement brought about by the F-SAW device manifests itself as enhanced biofouling removal efficiency of F-SAW throughout the device delay path compared to the conventional device, thereby providing enhanced device sensitivity, selectivity, and reusability. Furthermore, contrary to the conventional SAW in which the smallest particle is removable near the input IDTs, the F-SAW device removes the smallest particle near the device focal point. The results of this work are shown to have significant implications in typical biosensing and microfluidic applications. In a broader context, the results of the present study demonstrate a technique of enhancing streaming induced flows, which is of great importance to contemporary problems involving microfluidic and sensing applications of piezoelectric devices.

  12. Amplification and directional emission of surface acoustic waves by a two-dimensional electron gas

    SciTech Connect

    Shao, Lei; Pipe, Kevin P.

    2015-01-12

    Amplification of surface acoustic waves (SAWs) by electron drift in a two-dimensional electron gas (2DEG) is analyzed analytically and confirmed experimentally. Calculations suggest that peak power gain per SAW radian occurs at a more practical carrier density for a 2DEG than for a bulk material. It is also shown that SAW emission with tunable directionality can be achieved by modulating a 2DEG's carrier density (to effect SAW generation) in the presence of an applied DC field that amplifies SAWs propagating in a particular direction while attenuating those propagating in the opposite direction.

  13. Absorption of surface acoustic waves by graphene

    NASA Astrophysics Data System (ADS)

    Zhang, S. H.; Xu, W.

    2011-06-01

    We present a theoretical study on interactions of electrons in graphene with surface acoustic waves (SAWs). We find that owing to momentum and energy conservation laws, the electronic transition accompanied by the SAW absorption cannot be achieved via inter-band transition channels in graphene. For graphene, strong absorption of SAWs can be observed in a wide frequency range up to terahertz at room temperature. The intensity of SAW absorption by graphene depends strongly on temperature and can be adjusted by changing the carrier density. This study is relevant to the exploration of the acoustic properties of graphene and to the application of graphene as frequency-tunable SAW devices.

  14. Amplification and directional emission of surface acoustic waves by a two-dimensional electron gas

    NASA Astrophysics Data System (ADS)

    Shao, Lei; Pipe, Kevin P.

    2015-01-01

    Amplification of surface acoustic waves (SAWs) by electron drift in a two-dimensional electron gas (2DEG) is analyzed analytically and confirmed experimentally. Calculations suggest that peak power gain per SAW radian occurs at a more practical carrier density for a 2DEG than for a bulk material. It is also shown that SAW emission with tunable directionality can be achieved by modulating a 2DEG's carrier density (to effect SAW generation) in the presence of an applied DC field that amplifies SAWs propagating in a particular direction while attenuating those propagating in the opposite direction.

  15. Evaluation of Various Herbicides for Saw Greenbrier [Smilax bona-nox L.] and Southern Dewberry [Rubus trivialis Michx.] Control and Bermudagrass [Cynodon dactylon (L.) Pers.] Tolerance and Sharppod Morningglory [Ipomoea trichocarpa var. trichocarpa Ell.] Control in Roundup Ready Flex® and LibertyLink® Cotton Systems 

    E-print Network

    Janak, Travis Wayne

    2012-02-14

    to decrease Tifton 85 dry matter yield at the first harvest, with no effect observed at the second harvest. In 2007, both broadcast treatments containing triclopyr + fluroxypyr and the IPT treatment of triclopyr decreased dry matter yield at the first harvest...

  16. From life in the ocean to life in our living room carpet to life sciences in general, March saw College of Agriculture and Life Sciences' experts put pen to paper in an effort to make decisionmakers aware of significant challenges to

    E-print Network

    Angenent, Lars T.

    other scientists are"urging serious scientific investigation of the indoor biome." National:"EmergencyResponsefor MarineDiseases" 03.13.2015 Drew Harvell,ecology and evolutionary biology,and 10 other scientists show their support for the Marine Disease EmergencyAct. NBCNews:NewYorkAbuzzAbout Rats

  17. Theoretical analysis of surface acoustic wave propagating properties of Y-cut nano lithium niobate film on silicon dioxide

    NASA Astrophysics Data System (ADS)

    Chen, Jing; Zhang, Qiaozhen; Han, Tao; Zhou, Liu; Tang, Gongbin; Liu, Boquan; Ji, Xiaojun

    2015-08-01

    The surface acoustic wave (SAW) propagating characteristics of Y-cut nano LiNbO3 (LN) film on SiO2/LN substrate have been theoretically calculated. The simulated results showed a shear horizontal (SH) SAW with enhanced electromechanical coupling factor K2 owing to a dimensional effect of the nanoscale LN film. However, a Rayleigh SAW and two other resonances related to thickness vibrations caused spurious responses for wideband SAW devices. These spurious waves could be fully suppressed by properly controlling structural parameters including the electrode layer height, thickness, and the Euler angle (?) of the LN thin film. Finally, a pure SH SAW was obtained with a wide ? range, from 0° to 5° and 165° to 180°. The largest K2 achieved for the pure SH SAW was about 35.1%. The calculated results demonstrate the promising application of nano LN film to the realization of ultra-wideband SAW devices.

  18. Quantum Acoustics with Surface Acoustic Waves

    E-print Network

    Thomas Aref; Per Delsing; Maria K. Ekström; Anton Frisk Kockum; Martin V. Gustafsson; Göran Johansson; Peter Leek; Einar Magnusson; Riccardo Manenti

    2015-06-04

    It has recently been demonstrated that surface acoustic waves (SAWs) can interact with superconducting qubits at the quantum level. SAW resonators in the GHz frequency range have also been found to have low loss at temperatures compatible with superconducting quantum circuits. These advances open up new possibilities to use the phonon degree of freedom to carry quantum information. In this paper, we give a description of the basic SAW components needed to develop quantum circuits, where propagating or localized SAW-phonons are used both to study basic physics and to manipulate quantum information. Using phonons instead of photons offers new possibilities which make these quantum acoustic circuits very interesting. We discuss general considerations for SAW experiments at the quantum level and describe experiments both with SAW resonators and with interaction between SAWs and a qubit. We also discuss several potential future developments.

  19. [The comparative characteristics of sawcuts across the femoral bone].

    PubMed

    Sarkisian, B A; Azarov, P A

    2014-01-01

    The objective of the present work was to study the differences between the morphological features of the wounds in the long tubular bones inflicted by joinery hand saws designed for longitudinal and transverse, sawing. The experimental injuries to the femoral bones were inflicted by the recurring and reciprocating saw movements. The hand saws had 5 mm high "sharp" and "blunt"-tipped teeth. A total of 40 experiments were carried out. It was shown that the sawcuts across the femoral bones and their edges have different size, shape, and morphological characteristics (defects, ledges, projections, bright spots) depending on the type of the saw, the sharpness of its teeth, and the mode of sawing. The results of the study may be used to improve diagnostics of injuries to the long tubular bones inflicted by different types of joinery saws. PMID:25269172

  20. Surface acoustic wave devices on bulk ZnO crystals at low temperature

    NASA Astrophysics Data System (ADS)

    Magnusson, E. B.; Williams, B. H.; Manenti, R.; Nam, M.-S.; Nersisyan, A.; Peterer, M. J.; Ardavan, A.; Leek, P. J.

    2015-02-01

    Surface acoustic wave (SAW) devices based on thin films of ZnO are a well established technology. However, SAW devices on bulk ZnO crystals are not practical at room temperature due to the significant damping caused by finite electrical conductivity of the crystal. Here, by operating at low temperatures, we demonstrate effective SAW devices on the (0001) surface of bulk ZnO crystals, including a delay line operating at SAW wavelengths of ? = 4 and 6 ?m and a one-port resonator at a wavelength of ? = 1.6 ?m. We find that the SAW velocity is temperature dependent, reaching v ? 2.68 km/s at 10 mK. Our resonator reaches a maximum quality factor of Qi ? 1.5 × 105, demonstrating that bulk ZnO is highly viable for low temperature SAW applications. The performance of the devices is strongly correlated with the bulk conductivity, which quenches SAW transmission above 200 K.

  1. Comparison of Transmission Line Methods for Surface Acoustic Wave Modeling

    NASA Technical Reports Server (NTRS)

    Wilson, William; Atkinson, Gary

    2009-01-01

    Surface Acoustic Wave (SAW) technology is low cost, rugged, lightweight, extremely low power and can be used to develop passive wireless sensors. For these reasons, NASA is investigating the use of SAW technology for Integrated Vehicle Health Monitoring (IVHM) of aerospace structures. To facilitate rapid prototyping of passive SAW sensors for aerospace applications, SAW models have been developed. This paper reports on the comparison of three methods of modeling SAWs. The three models are the Impulse Response Method (a first order model), and two second order matrix methods; the conventional matrix approach, and a modified matrix approach that is extended to include internal finger reflections. The second order models are based upon matrices that were originally developed for analyzing microwave circuits using transmission line theory. Results from the models are presented with measured data from devices. Keywords: Surface Acoustic Wave, SAW, transmission line models, Impulse Response Method.

  2. Analysis of two dimensional composite surface grating structures with applications to low loss microacoustic resonators

    NASA Astrophysics Data System (ADS)

    Yantchev, Ventsislav; Plessky, Victor

    2013-08-01

    2D composite grating building blocks with hexagonal symmetry are proposed and analyzed as efficient reflectors and transducers in the design of low loss surface acoustic wave (SAW) resonators. Eigen-frequency and frequency response finite element analyses are used to study the propagation and excitation characteristics of SAWs in the 2D composite structures. The proposed structures have the advantage of being compatible with the planar SAW technology, while introducing design principles reminiscent to the semiconductor devices. More specifically, the frequency bandgap characteristics of the various resonator building blocks can be adjusted so that losses related to the SAW diffraction, impedance mismatch, and parasitic SAW radiation from the electrical contacts can be suppressed. Three distinct types SAW resonant topologies employing 2D gratings are deduced from the analytical results.

  3. Conformal Invariance Predictions for the Three-Dimensional Self-Avoiding Walk

    NASA Astrophysics Data System (ADS)

    Kennedy, Tom

    2015-03-01

    If the three dimensional self-avoiding walk (SAW) is conformally invariant, then one can compute the hitting densities for the SAW in a half-space and in a sphere (Kennedy in Phys Rev Lett 111: 165703, 2013). The ensembles of SAW's used to define these hitting densities involve walks of arbitrary lengths, and so these ensembles cannot be directly studied by the pivot Monte Carlo algorithm for the SAW. We show that these mixed length ensembles should have the same scaling limit as certain weighted ensembles that only involve walks with a single length, thus providing a fast method for simulating these ensembles. Preliminary simulations which found good agreement between the predictions and Monte Carlo simulations for the SAW were reported in Kennedy (Phys Rev Lett 111: 165703, 2013). In this paper we present more accurate simulations testing the predictions and find even stronger support for the prediction that the SAW is conformally invariant in three dimensions.

  4. Confinement of surface acoustic waves in AlN /GaN/?-LiAlO2 acoustic wells

    NASA Astrophysics Data System (ADS)

    Takagaki, Y.; Chilla, E.; Ploog, K. H.

    2005-02-01

    We numerically investigate the characteristics of surface acoustic waves (SAWs) in AlN /GaN/?-LiAlO2 heterostructures. The markedly large sound velocity in AlN in comparison to that in GaN leads to an expulsion of SAWs from the top AlN layer and their resultant relocation to the middle GaN layer in the short-wavelength regime. The SAW velocity in the limit of zero wavelength is given by a bulk sound velocity of GaN, owing to the capping by the AlN barrier layer. The extra confinement of the SAW power in the acoustic well is advantageous in manipulating the operation of GaN-based devices by SAWs. The threshold velocity for the appearance of guided Rayleigh-like modes is found to be smaller than the bulk transverse sound velocity in the substrate. The present system exhibits furthermore unusual bowing behavior in the SAW dispersion.

  5. 41. SOUTHEAST ACROSS WOODWORKING SHOP AREA IN NORTHWESTERN QUADRANT OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. SOUTHEAST ACROSS WOODWORKING SHOP AREA IN NORTHWESTERN QUADRANT OF FACTORY SHOWING ON LEFT CIRCA 1900 CROSS-CUTOFF CIRCULAR SAW AND ON RIGHT CIRCA 1900 TABLE SAW. BEHIND THE CROSS-CUTOFF SAW IS A CIRCA 1900 SNAG GRINDER. IN THE CENTER BACKGROUND IS THE CIRCA 1900 MICHIGAN MACHINERY MFG. CO. PUNCH PRESS. - Kregel Windmill Company Factory, 1416 Central Avenue, Nebraska City, Otoe County, NE

  6. Microscopic carrier dynamics in quantum wells modulated by high-frequency lateral fields

    NASA Astrophysics Data System (ADS)

    Santos, P. V.; Alsina, F.; Zhang, S. K.; Hey, R.; García-Cristóbal, A.; Cantarero, A.

    2002-03-01

    We have investigated the dynamics of photogenerated carriers in GaAs quantum wells under the influence of high-frequency fields produced by metal gratings and by surface acoustic waves (SAW's) using spatially and time-resolved photoluminescence (PL). The frequency and phase of the PL oscillations induced by the high-frequency field yield information about the spatial distribution of the carriers and, in the case of SAW's, about the band-gap modulation induced by the SAW strain.

  7. Dynamic carrier distribution in quantum wells modulated by surface acoustic waves

    NASA Astrophysics Data System (ADS)

    Alsina, F.; Santos, P. V.; Hey, R.; García-Cristóbal, A.; Cantarero, A.

    2001-07-01

    We have investigated the dynamics of photogenerated carriers under surface acoustic wave (SAW) fields in GaAs quantum wells using spatially and time-resolved photoluminescence (PL). The frequency and phase of the PL oscillations under a SAW yield information about the carrier distribution and the band-gap modulation induced by the SAW. We directly prove that the transport properties of the carriers ultimately control their distribution, storage and, subsequent recombination in the modulated potential.

  8. Beef Cattle Management During Drouth. 

    E-print Network

    Sprott, J. Michael

    1971-01-01

    and oscillating fingers were installed to pre- vent their bending and catching on the extracting saws; 8 BULLETIN NO. 580, TEXAS AGRICULTURAL EXPERIMENT STATION Figure 3. Rear view of Texas Station Cotton Harvester and Bur Extractor showing harvested... and extracted cotton in trailer. (3) A reclaiming saw was placed below the stationary and oscillating fingers and adjacent to the main extracting saw to reclaim cotton that dropped through the fingers with the burs; (4) Stationary fingers of spring steel...

  9. 32 CFR 552.127 - Prohibitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Control of Firearms, Ammunition and Other Dangerous... shotgun. (2) Sawed-off rifle. (3) Machine gun and automatic weapons. (4) Silencers. (5)...

  10. 32 CFR 552.127 - Prohibitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Control of Firearms, Ammunition and Other Dangerous... shotgun. (2) Sawed-off rifle. (3) Machine gun and automatic weapons. (4) Silencers. (5)...

  11. 32 CFR 552.127 - Prohibitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Control of Firearms, Ammunition and Other Dangerous... shotgun. (2) Sawed-off rifle. (3) Machine gun and automatic weapons. (4) Silencers. (5)...

  12. 32 CFR 552.127 - Prohibitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Control of Firearms, Ammunition and Other Dangerous... shotgun. (2) Sawed-off rifle. (3) Machine gun and automatic weapons. (4) Silencers. (5)...

  13. 32 CFR 552.127 - Prohibitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Control of Firearms, Ammunition and Other Dangerous... shotgun. (2) Sawed-off rifle. (3) Machine gun and automatic weapons. (4) Silencers. (5)...

  14. Characterization and control of terpene emissions in Finnish sawmills.

    PubMed

    Welling, I; Mielo, T; Räisänen, J; Hyvärinen, M; Liukkonen, T; Nurkka, T; Lonka, P; Rosenberg, C; Peltonen, Y; Svedberg, U; Jäppinen, P

    2001-01-01

    This article describes an experimental study of terpene emission rates during fresh pine and spruce sawing and processing. Total terpene emission was determined by summing the product of the exhaust airflow rate and the mean concentration in the exhaust. Terpene concentrations were measured at fixed sampling points between the sawing lines. Terpene emission during pine sawing was found to be around 10 times greater than that during spruce sawing. The emission rates given here can be used to predict emission rates for various production rates. The predicted emission rates can be used in mass balance models to predict concentrations or required airflow rates to achieve the target concentration level. PMID:11331989

  15. Surface Acoustic Wave Frequency Comb

    E-print Network

    Savchenkov, A A; Ilchenko, V S; Seidel, D; Maleki, L

    2011-01-01

    We report on realization of an efficient triply-resonant coupling between two long lived optical modes and a high frequency surface acoustic wave (SAW) mode of the same monolithic crystalline whispering gallery mode resonator. The coupling results in an opto-mechanical oscillation and generation of a monochromatic SAW. A strong nonlinear interaction of this mechanical mode with other equidistant SAW modes leads to mechanical hyper-parametric oscillation and generation of a SAW pulse train and associated frequency comb in the resonator. We visualized the comb observing the modulation of the modulated light escaping the resonator.

  16. Surface acoustic wave opto-mechanical oscillator and frequency comb generator.

    PubMed

    Savchenkov, A A; Matsko, A B; Ilchenko, V S; Seidel, D; Maleki, L

    2011-09-01

    We report on realization of an efficient triply resonant coupling between two long lived optical modes and a high frequency surface acoustic wave (SAW) mode of the same monolithic crystalline whispering gallery mode resonator. The coupling results in an opto-mechanical oscillation and generation of a monochromatic SAW. A strong nonlinear interaction of this mechanical mode with other equidistant SAW modes leads to mechanical hyperparametric oscillation and generation of a SAW pulse train and associated frequency comb in the resonator. We visualized the comb by observing the modulation of the light escaping the resonator. PMID:21886203

  17. Bone-dust in autopsies: reduction of spreading.

    PubMed

    Kernbach-Wighton, G; Kuhlencord, A; Rossbach, K; Fischer, G

    1996-12-01

    During autopsies, an open oscillating saw produces large quantities of respirable bone-dust, which is able to carry microbes over several metres. Experiments were done using a modified (open) undulation saw (spray tube to moisten the saw-blade with water). Saw-dust was asservated with culture media. Colonies were identified macroscopically. Microbes in the air were quantified (per unit of time). A remarkable reduction of saw-dust is done by an integrated spray tube using water. There remains a contamination at the head of the autopsy table in the level of the table top. We found a complete decontamination 150 cm above the floor. No spreading of particles carrying microbes was seen over distances of more than 1.5 m. The risk of an airborne infection is minimal when using a manual saw (absence of grinding-dust). The modified type of an 'oscillating saw with a spray-tube' may be considered a practicable compromise between a manual saw and an unprotected undulation saw. It is necessary to complete the precautions against airborne infections by breath masks and safety-goggles. PMID:9022272

  18. Bendable ZnO thin film surface acoustic wave devices on polyethylene terephthalate substrate

    SciTech Connect

    He, Xingli; Guo, Hongwei; Chen, Jinkai; Wang, Wenbo; Xuan, Weipeng; Xu, Yang E-mail: jl2@bolton.ac.uk; Luo, Jikui E-mail: jl2@bolton.ac.uk

    2014-05-26

    Bendable surface acoustic wave (SAW) devices were fabricated using high quality c-axis orientation ZnO films deposited on flexible polyethylene terephthalate substrates at 120?°C. Dual resonance modes, namely, the zero order pseudo asymmetric (A{sub 0}) and symmetric (S{sub 0}) Lamb wave modes, have been obtained from the SAW devices. The SAW devices perform well even after repeated flexion up to 2500??? for 100 times, demonstrating its suitability for flexible electronics application. The SAW devices are also highly sensitive to compressive and tensile strains, exhibiting excellent anti-strain deterioration property, thus, they are particularly suitable for sensing large strains.

  19. 21 CFR 878.4820 - Surgical instrument motors and accessories/attachments.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... bone and soft tissue. Accessories or attachments may include a bur, chisel (osteotome), dermabrasion brush, dermatome, drill bit, hammerhead, pin driver, and saw blade. (b) Classification. Class I...

  20. Surface acoustic wave pressure transducers and accelerometers

    NASA Astrophysics Data System (ADS)

    Rokhlin, S. I.; Kornblit, L.; Gorodetsky, G.

    This study analyzes a new class of force sensors (accelerometers and pressure sensors), based on miniature surface acoustic wave (SAW) resonators. The expected performance of SAW accelerometers and pressure transducers is estimated and compared with published data. It is shown that an ideal SAW accelerometer has a performance comparable with high-quality force-balanced servo accelerometers. However, the attainment of the required dynamic range and resolution may hinder the design of a prototype. The performance of the best laboratory SAW pressure sensors is already comparable in precision with the digital-pressure transducers employing an intricately-shaped quartz resonator.