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Sample records for add subtract multiply

  1. Floating Point Multiply-Add-Subtract Implementation

    DTIC Science & Technology

    2014-11-07

    implementation receives two floating point numbers Ain and Bin. The floating point number is separated into component parts for processing. For this purpose...in FIG. 2 the mantissa of Ain is identified as Aman, and the mantissa of Bin is identified as Bman. The exponent of Ain is identified as Aexp, and...unit implementation 10 receives Ain and Bin in a floating point format that can be broken up into signs, mantissas, and exponents. These numbers

  2. A multiply-add engine with monolithically integrated 3D memristor crossbar/CMOS hybrid circuit.

    PubMed

    Chakrabarti, B; Lastras-Montaño, M A; Adam, G; Prezioso, M; Hoskins, B; Cheng, K-T; Strukov, D B

    2017-02-14

    Silicon (Si) based complementary metal-oxide semiconductor (CMOS) technology has been the driving force of the information-technology revolution. However, scaling of CMOS technology as per Moore's law has reached a serious bottleneck. Among the emerging technologies memristive devices can be promising for both memory as well as computing applications. Hybrid CMOS/memristor circuits with CMOL (CMOS + "Molecular") architecture have been proposed to combine the extremely high density of the memristive devices with the robustness of CMOS technology, leading to terabit-scale memory and extremely efficient computing paradigm. In this work, we demonstrate a hybrid 3D CMOL circuit with 2 layers of memristive crossbars monolithically integrated on a pre-fabricated CMOS substrate. The integrated crossbars can be fully operated through the underlying CMOS circuitry. The memristive devices in both layers exhibit analog switching behavior with controlled tunability and stable multi-level operation. We perform dot-product operations with the 2D and 3D memristive crossbars to demonstrate the applicability of such 3D CMOL hybrid circuits as a multiply-add engine. To the best of our knowledge this is the first demonstration of a functional 3D CMOL hybrid circuit.

  3. A multiply-add engine with monolithically integrated 3D memristor crossbar/CMOS hybrid circuit

    NASA Astrophysics Data System (ADS)

    Chakrabarti, B.; Lastras-Montaño, M. A.; Adam, G.; Prezioso, M.; Hoskins, B.; Cheng, K.-T.; Strukov, D. B.

    2017-02-01

    Silicon (Si) based complementary metal-oxide semiconductor (CMOS) technology has been the driving force of the information-technology revolution. However, scaling of CMOS technology as per Moore’s law has reached a serious bottleneck. Among the emerging technologies memristive devices can be promising for both memory as well as computing applications. Hybrid CMOS/memristor circuits with CMOL (CMOS + “Molecular”) architecture have been proposed to combine the extremely high density of the memristive devices with the robustness of CMOS technology, leading to terabit-scale memory and extremely efficient computing paradigm. In this work, we demonstrate a hybrid 3D CMOL circuit with 2 layers of memristive crossbars monolithically integrated on a pre-fabricated CMOS substrate. The integrated crossbars can be fully operated through the underlying CMOS circuitry. The memristive devices in both layers exhibit analog switching behavior with controlled tunability and stable multi-level operation. We perform dot-product operations with the 2D and 3D memristive crossbars to demonstrate the applicability of such 3D CMOL hybrid circuits as a multiply-add engine. To the best of our knowledge this is the first demonstration of a functional 3D CMOL hybrid circuit.

  4. A multiply-add engine with monolithically integrated 3D memristor crossbar/CMOS hybrid circuit

    PubMed Central

    Chakrabarti, B.; Lastras-Montaño, M. A.; Adam, G.; Prezioso, M.; Hoskins, B.; Cheng, K.-T.; Strukov, D. B.

    2017-01-01

    Silicon (Si) based complementary metal-oxide semiconductor (CMOS) technology has been the driving force of the information-technology revolution. However, scaling of CMOS technology as per Moore’s law has reached a serious bottleneck. Among the emerging technologies memristive devices can be promising for both memory as well as computing applications. Hybrid CMOS/memristor circuits with CMOL (CMOS + “Molecular”) architecture have been proposed to combine the extremely high density of the memristive devices with the robustness of CMOS technology, leading to terabit-scale memory and extremely efficient computing paradigm. In this work, we demonstrate a hybrid 3D CMOL circuit with 2 layers of memristive crossbars monolithically integrated on a pre-fabricated CMOS substrate. The integrated crossbars can be fully operated through the underlying CMOS circuitry. The memristive devices in both layers exhibit analog switching behavior with controlled tunability and stable multi-level operation. We perform dot-product operations with the 2D and 3D memristive crossbars to demonstrate the applicability of such 3D CMOL hybrid circuits as a multiply-add engine. To the best of our knowledge this is the first demonstration of a functional 3D CMOL hybrid circuit. PMID:28195239

  5. A phase retrieval method of interferograms add-subtracting based on two-step phase shifting.

    PubMed

    Xu, Yuanyuan; Wang, Yawei; Ji, Ying; Jin, Weifeng; Bu, Min; Shang, Xuefu

    2014-01-01

    A phase retrieval method is introduced in quantitative phase imaging (QPI) based on two-step phase-shifting technique. By acquiring two measured interferograms and calculating the addition and subtraction between them, the quantitative phase information can be directly retrieved. This method is illustrated by both theory and simulation experiments of a ball. The results of the simulation and the experiment of the red blood cell show a good agreement, demonstrating its application for studying cells.

  6. Add neurons, subtract anxiety

    PubMed Central

    Kheirbek, Mazen A.; Hen, René

    2014-01-01

    IN BRIEF To keep memories from becoming jumbled, the brain must encode the distinct features of events and situations in a way that allows them to be distinguished from one another—a process called pattern separation. Pattern separation enables us to distinguish dangerous situations from similar ones that pose no risk. People with defects in this ability may be prone to anxiety disorders. The process occurs in one of the two regions of the brain that generate neurons throughout life. These fledgling cells seem to be critical to pattern separation. Interventions that specifically boost the ranks of rookie neurons could provide new ways to regulate mood and possibly treat conditions such as post-traumatic stress disorder. PMID:24974712

  7. Hardware multiplier processor

    DOEpatents

    Pierce, P.E.

    A hardware processor is disclosed which in the described embodiment is a memory mapped multiplier processor that can operate in parallel with a 16 bit microcomputer. The multiplier processor decodes the address bus to receive specific instructions so that in one access it can write and automatically perform single or double precision multiplication involving a number written to it with or without addition or subtraction with a previously stored number. It can also, on a single read command automatically round and scale a previously stored number. The multiplier processor includes two concatenated 16 bit multiplier registers, two 16 bit concatenated 16 bit multipliers, and four 16 bit product registers connected to an internal 16 bit data bus. A high level address decoder determines when the multiplier processor is being addressed and first and second low level address decoders generate control signals. In addition, certain low order address lines are used to carry uncoded control signals. First and second control circuits coupled to the decoders generate further control signals and generate a plurality of clocking pulse trains in response to the decoded and address control signals.

  8. Hardware multiplier processor

    DOEpatents

    Pierce, Paul E.

    1986-01-01

    A hardware processor is disclosed which in the described embodiment is a memory mapped multiplier processor that can operate in parallel with a 16 bit microcomputer. The multiplier processor decodes the address bus to receive specific instructions so that in one access it can write and automatically perform single or double precision multiplication involving a number written to it with or without addition or subtraction with a previously stored number. It can also, on a single read command automatically round and scale a previously stored number. The multiplier processor includes two concatenated 16 bit multiplier registers, two 16 bit concatenated 16 bit multipliers, and four 16 bit product registers connected to an internal 16 bit data bus. A high level address decoder determines when the multiplier processor is being addressed and first and second low level address decoders generate control signals. In addition, certain low order address lines are used to carry uncoded control signals. First and second control circuits coupled to the decoders generate further control signals and generate a plurality of clocking pulse trains in response to the decoded and address control signals.

  9. MULTIPLIER CIRCUIT

    DOEpatents

    Chase, R.L.

    1963-05-01

    An electronic fast multiplier circuit utilizing a transistor controlled voltage divider network is presented. The multiplier includes a stepped potentiometer in which solid state or transistor switches are substituted for mechanical wipers in order to obtain electronic switching that is extremely fast as compared to the usual servo-driven mechanical wipers. While this multiplier circuit operates as an approximation and in steps to obtain a voltage that is the product of two input voltages, any desired degree of accuracy can be obtained with the proper number of increments and adjustment of parameters. (AEC)

  10. MULTIPLIER CIRCUIT

    DOEpatents

    Thomas, R.E.

    1959-01-20

    An electronic circuit is presented for automatically computing the product of two selected variables by multiplying the voltage pulses proportional to the variables. The multiplier circuit has a plurality of parallel resistors of predetermined values connected through separate gate circults between a first input and the output terminal. One voltage pulse is applied to thc flrst input while the second voltage pulse is applied to control circuitry for the respective gate circuits. Thc magnitude of the second voltage pulse selects the resistors upon which the first voltage pulse is imprcssed, whereby the resultant output voltage is proportional to the product of the input voltage pulses

  11. Tuckshop Subtraction

    ERIC Educational Resources Information Center

    Duke, Roger; Graham, Alan; Johnston-Wilder, Sue

    2007-01-01

    This article describes a recent and successful initiative on teaching place value and the decomposition method of subtraction to pupils having difficulty with this technique in the 9-12-year age range. The aim of the research was to explore whether using the metaphor of selling chews (i.e., sweets) in a tuck shop and developing this into an iconic…

  12. ELECTRONIC MULTIPLIER

    DOEpatents

    Collier, D.M.; Meeks, L.A.; Palmer, J.P.

    1961-01-31

    S>An electronic multiplier is described for use in analog computers. Two electrical input signals are received; one controls the slope of a saw-tooth voltage wave while the other controls the time duration of the wave. A condenser and diode clamps are provided to sustain the crest voltage reached by the wave, and for storing that voltage to provide an output signal which is a steady d-c voltage.

  13. Elementary subtraction.

    PubMed

    Seyler, Donald J; Kirk, Elizabeth P; Ashcraft, Mark H

    2003-11-01

    Four experiments examined performance on the 100 "basic facts" of subtraction and found a discontinuous "stair step" function for reaction times and errors beginning with 11 - n facts. Participants' immediate retrospective reports of nonretrieval showed the same pattern in Experiment 3. The degree to which elementary subtraction depends on working memory (WM) was examined in a dual-task paradigm in Experiment 4. The reconstructive processing used with larger basic facts was strongly associated with greater WM disruption, as evidenced by errors in the secondary task: this was especially the case for participants with lower WM spans. The results support the R. S. Siegler and E. Jenkins (1989) distribution of associations model, although discriminating among the alternative solution processes appears to be a serious challenge.

  14. Behavior subtraction.

    PubMed

    Jodoin, Pierre-Marc; Saligrama, Venkatesh; Konrad, Janusz

    2012-09-01

    Background subtraction has been a driving engine for many computer vision and video analytics tasks. Although its many variants exist, they all share the underlying assumption that photometric scene properties are either static or exhibit temporal stationarity. While this works in many applications, the model fails when one is interested in discovering changes in scene dynamics instead of changes in scene's photometric properties; the detection of unusual pedestrian or motor traffic patterns are but two examples. We propose a new model and computational framework that assume the dynamics of a scene, not its photometry, to be stationary, i.e., a dynamic background serves as the reference for the dynamics of an observed scene. Central to our approach is the concept of an event, which we define as short-term scene dynamics captured over a time window at a specific spatial location in the camera field of view. Unlike in our earlier work, we compute events by time-aggregating vector object descriptors that can combine multiple features, such as object size, direction of movement, speed, etc. We characterize events probabilistically, but use low-memory, low-complexity surrogates in a practical implementation. Using these surrogates amounts to behavior subtraction, a new algorithm for effective and efficient temporal anomaly detection and localization. Behavior subtraction is resilient to spurious background motion, such as due to camera jitter, and is content-blind, i.e., it works equally well on humans, cars, animals, and other objects in both uncluttered and highly cluttered scenes. Clearly, treating video as a collection of events rather than colored pixels opens new possibilities for video analytics.

  15. Pipeline active filter utilizing a booth type multiplier

    NASA Technical Reports Server (NTRS)

    Nathan, Robert (Inventor)

    1987-01-01

    Multiplier units of the modified Booth decoder and carry-save adder/full adder combination are used to implement a pipeline active filter wherein pixel data is processed sequentially, and each pixel need only be accessed once and multiplied by a predetermined number of weights simultaneously, one multiplier unit for each weight. Each multiplier unit uses only one row of carry-save adders, and the results are shifted to less significant multiplier positions and one row of full adders to add the carry to the sum in order to provide the correct binary number for the product Wp. The full adder is also used to add this product Wp to the sum of products .SIGMA.Wp from preceding multiply units. If m.times.m multiplier units are pipelined, the system would be capable of processing a kernel array of m.times.m weighting factors.

  16. ELECTRONIC MULTIPLIER CIRCUIT

    DOEpatents

    Thomas, R.E.

    1959-08-25

    An electronic multiplier circuit is described in which an output voltage having an amplitude proportional to the product or quotient of the input signals is accomplished in a novel manner which facilitates simplicity of circuit construction and a high degree of accuracy in accomplishing the multiplying and dividing function. The circuit broadly comprises a multiplier tube in which the plate current is proportional to the voltage applied to a first control grid multiplied by the difference between voltage applied to a second control grid and the voltage applied to the first control grid. Means are provided to apply a first signal to be multiplied to the first control grid together with means for applying the sum of the first signal to be multiplied and a second signal to be multiplied to the second control grid whereby the plate current of the multiplier tube is proportional to the product of the first and second signals to be multiplied.

  17. SECONDARY ELECTRON MULTIPLIERS

    DOEpatents

    Morton, G.A.; Green, M.W.

    1959-01-01

    A secondary emission multiplier having exceptionally high output signal current is described. In previous multiplier tubes the output signal current was limited by the space charge surrounding the electrodes. The present multiplier tubes provides a source of ions within the tube adjacent the anode to neutralize the space charge effect, and the dynode voltage is switched on intermittently for periods of time so brief that the ions do not move towards the cathode.

  18. Pressure multiplying dispenser

    DOEpatents

    DeFord, Henry S.; Moss, Owen R.

    1986-01-01

    A pressure multiplying dispenser for delivering fluid, preferably as a spray to the atmosphere, from a source of fluid, preferably a spray bottle, is described. The dispenser includes in combination a hollow cylindrical member, a nozzle delivery tube within the cylindrical member and a hollow actuator piston slideable within the cylindrical member which acts to multiply the pressure of a squeeze applied to the spray bottle.

  19. The Multiply Handicapped Child.

    ERIC Educational Resources Information Center

    Wolf, James M., Ed.; Anderson, Robert M., Ed.

    Articles presented in the area of the medical and educational challenge of the multiply handicapped child are an overview of the problem, the increasing challenge, congenital malformations, children whose mothers had rubella, prematurity and deafness, the epidemiology of reproductive casualty, and new education for old problems. Discussions of…

  20. Omega, the final multiplier

    NASA Astrophysics Data System (ADS)

    Buckley, T. N.

    2008-12-01

    The application of optimisation theory to vegetation processes has rarely extended beyond the context of diurnal to intra-annual gas exchange of individual leaves and crowns. One reason is that the Lagrange multipliers in the leaf-scale solutions, which are marginal products for allocatable photosynthetic resource inputs (water and nitrogen), are mysterious in origin, and their numerical values are difficult to measure -- let alone to predict or interpret in concrete physiological or ecological terms. These difficulties disappear, however, when the optimisation paradigm itself is extended to encompass carbon allocation and growth at the lifespan scale. The trajectories of leaf (and canopy) level marginal products are then implicit in the trajectory of plant and stand structure predicted by optimal carbon allocation. Furthermore, because the input and product are the same resource -- carbon -- in the whole plant optimisation, the product in one time step defines the input constraint, and hence implicitly the marginal product for carbon, in the next time step. This effectively converts the problem from a constrained optimisation of a definite integral, in which the multipliers are undetermined, to an unconstrained maximisation of a state, in which the multipliers are all implicit. This talk will explore how the marginal products for photosynthetic inputs as well as the marginal product for carbon -- i.e., the 'final multiplier,' omega -- are predicted to vary over time and in relation to environmental change during tree growth.

  1. Suppression subtractive hybridization.

    PubMed

    Ghorbel, Mohamed T; Murphy, David

    2011-01-01

    Comparing two RNA populations that differ from the effects of a single independent variable, such as a drug treatment or a specific genetic defect, can establish differences in the abundance of specific transcripts that vary in a population dependent manner. There are different methods for identifying differentially expressed genes. These methods include microarray, Serial Analysis of Gene Expression (SAGE), and quantitative Reverse-Transcriptase Polymerase Chain Reaction (qRT-PCR). Herein, the protocol describes an easy and cost-effective alternative that does not require prior knowledge of the transcriptomes under examination. It is specifically relevant when low levels of RNA starting material are available. This protocol describes the use of Switching Mechanism At RNA Termini Polymerase Chain Reaction (SMART-PCR) to amplify cDNA from small amounts of RNA. The amplified cDNA populations under comparison are then subjected to Suppression Subtractive Hybridization (SSH-PCR). SSH-PCR is a technique that couples subtractive hybridization with suppression PCR to selectively amplify fragments of differentially expressed genes. The resulting products are cDNA populations enriched for significantly overrepresented transcripts in either of the two input RNAs. These cDNA populations can then be cloned to generate subtracted cDNA library. Microarrays made with clones from the subtracted forward and reverse cDNA libraries are then screened for differentially expressed genes using targets generated from tester and driver total RNAs.

  2. Subtraction at NNLO

    NASA Astrophysics Data System (ADS)

    Frixione, Stefano; Grazzini, Massimiliano

    2005-06-01

    We propose a framework for the implementation of a subtraction formalism at NNLO in QCD, based on an observable- and process-independent cancellation of infrared singularities. As a first simple application, we present the calculation of the contribution to the e+e- dijet cross section proportional to CFTR.

  3. Why Multiply by "g"?

    ERIC Educational Resources Information Center

    Nelson, Jane Bray

    2012-01-01

    As a new physics teacher, I was explaining how to find the weight of an object sitting on a table near the surface of the Earth. It bothered me when a student asked, "The object is not accelerating so why do you multiply the mass of the object by the acceleration due to gravity?" I answered something like, "That's true, but if the table were not…

  4. Monolithic THz Frequency Multipliers

    NASA Technical Reports Server (NTRS)

    Erickson, N. R.; Narayanan, G.; Grosslein, R. M.; Martin, S.; Mehdi, I.; Smith, P.; Coulomb, M.; DeMartinez, G.

    2001-01-01

    Frequency multipliers are required as local oscillator sources for frequencies up to 2.7 THz for FIRST and airborne applications. Multipliers at these frequencies have not previously been demonstrated, and the object of this work was to show whether such circuits are really practical. A practical circuit is one which not only performs as well as is required, but also can be replicated in a time that is feasible. As the frequency of circuits is increased, the difficulties in fabrication and assembly increase rapidly. Building all of the circuit on GaAs as a monolithic circuit is highly desirable to minimize the complexity of assembly, but at the highest frequencies, even a complete monolithic circuit is extremely small, and presents serious handling difficulty. This is compounded by the requirement for a very thin substrate. Assembly can become very difficult because of handling problems and critical placement. It is very desirable to make the chip big enough to that it can be seen without magnification, and strong enough that it may be picked up with tweezers. Machined blocks to house the chips present an additional challenge. Blocks with complex features are very expensive, and these also imply very critical assembly of the parts. It would be much better if the features in the block were as simple as possible and non-critical to the function of the chip. In particular, grounding and other electrical interfaces should be done in a manner that is highly reproducible.

  5. Pediatric digital subtraction angiography

    SciTech Connect

    Amundson, G.M.; Wesenberg, R.L.; Mueller, D.L.; Reid, R.H.

    1984-12-01

    Experience with intravenous digital subtraction angiography (DSA) in infants and children is limited, although its relative rate of performance, low complication rate, and diagnostic accuracy indicate great potential. The authors performed 87 DSA examinations (74 patients) and obtained sufficient detail to facilitate diagnosis in most cases. The major problems of patient movement and overlapping vessels can be minimized by judicious use of sedation and strict attention to technique. Exposure of patients to radiation has not been a limiting factor since our system uses low exposure factors. Our results demonstrate that DSA has wide applicability to many organ systems and is especially useful in intracranial disease and for preoperative evaluation of neoplasms.

  6. Multiplier operator algebras and applications

    PubMed Central

    Blecher, David P.; Zarikian, Vrej

    2004-01-01

    The one-sided multipliers of an operator space X are a key to “latent operator algebraic structure” in X. We begin with a survey of these multipliers, together with several of the applications that they have had to operator algebras. We then describe several new results on one-sided multipliers, and new applications, mostly to one-sided M-ideals. PMID:14711990

  7. Hardware Implementation of a Bilateral Subtraction Filter

    NASA Technical Reports Server (NTRS)

    Huertas, Andres; Watson, Robert; Villalpando, Carlos; Goldberg, Steven

    2009-01-01

    its position in the window as well as the pixel value for the central pixel of the window. The absolute difference between these two pixel values is calculated and used as an address in a lookup table. Each processing element has a lookup table, unique for its position in the window, containing the weight coefficients for the Gaussian function for that position. The pixel value is multiplied by the weight, and the outputs of the processing element are the weight and pixel-value weight product. The products and weights are fed to the adder tree. The sum of the products and the sum of the weights are fed to the divider, which computes the sum of products the sum of weights. The output of the divider is denoted the bilateral smoothed image. The smoothing function is a simple weighted average computed over a 3 3 subwindow centered in the 9 9 window. After smoothing, the image is delayed by an additional amount of time needed to match the processing time for computing the bilateral smoothed image. The bilateral smoothed image is then subtracted from the 3 3 smoothed image to produce the final output. The prototype filter as implemented in a commercially available FPGA processes one pixel per clock cycle. Operation at a clock speed of 66 MHz has been demonstrated, and results of a static timing analysis have been interpreted as suggesting that the clock speed could be increased to as much as 100 MHz.

  8. Torque multiplier subsea tool

    SciTech Connect

    Leicht, F. M.; Baugh, B. F.; Palany, H. C.

    1985-10-22

    A torque multiplier subsea tool for setting a seal between a casing hanger and a subsea wellhead includes a mandrel having a sun gear with axial elongate teeth. An outer barrel is disposed around the mandrel forming an annulus therebetween. A planetary gear assembly is disposed in the annulus between the barrel and the sun gear to transmit to the barrel a torque which is higher in magnitude than that applied to the mandrel. A connector body disposed around the mandrel, below the planetary gear assembly, includes radially movable dogs for engaging the casing hanger. The barrel engages the sealing assembly and transmits the increased torque thereto to advance the sealing assembly downwards and to set the seal. The mandrel advances downwards with the sealing assembly and releases the dogs from the casing hanger. An emergency release mechanism is provided to advance the mandrel downwards to release the dogs in the event such downward movement is prevented during normal seal setting operation.

  9. Multiplying with Neurons

    NASA Astrophysics Data System (ADS)

    Gabbiani, F.; Krapp, H.; Koch, C.; Laurent, G.

    1998-03-01

    LGMD and DCMD are a pair of identified neurons in the locust brain thought to be involved in visually triggered escape behavior. LGMD integrates visual inputs in its dendritic arbor, converts them into spikes transmitted in a 1:1 manner to DCMD which relays this information to motor centers. We measured the spike activity of DCMD during simulated object approach and observed that its peak occured prior to the expected collision. The time difference between peak activity and collision depended linearly on the ratio of object size to approach velocity, as expected if LGMD/DCMD were detecting the moment in time when the approaching object reaches a fixed angular threshold θ_thresh on the locust's retina. The response of LGMD/DCMD could be fitted by multiplying the angular velocity at which an approaching object is increasing in size over the retina, dot θ, with an exponential function of the object's angular size, θ: f(t) = g(dot θ(t-δ) e^-α θ(t-δ)) where g is a static non-linearity, α a constant related to the angular threshold detected by LGMD/DCMD (θ_thresh = arctan (2/α)) and δ denotes the lag of the neuronal response with respect to the stimulus. This suggests that LGMD/DCMD derives its angular threshold sensitivity by multiplying dot θ with an exponential of θ. A biophysical implementation would be through linear summation of excitatory and inhibitory inputs proportional to log(dot θ) and -α θ, followed by a conversion to spike rate according to the static non-linearity (g circ exp). We have performed several experiments to test this hypothesis.

  10. Pulse subtraction Doppler

    NASA Astrophysics Data System (ADS)

    Mahue, Veronique; Mari, Jean Martial; Eckersley, Robert J.; Caro, Colin G.; Tang, Meng-Xing

    2010-01-01

    Recent advances have demonstrated the feasibility of molecular imaging using targeted microbubbles and ultrasound. One technical challenge is to selectively detect attached bubbles from those freely flowing bubbles and surrounding tissue. Pulse Inversion Doppler is an imaging technique enabling the selective detection of both static and moving ultrasound contrast agents: linear scatterers generate a single band Doppler spectrum, while non-linear scatterers generate a double band spectrum, one being uniquely correlated with the presence of contrast agents and non-linear tissue signals. We demonstrate that similar spectrums, and thus the same discrimination, can be obtained through a Doppler implementation of Pulse Subtraction. This is achieved by reconstructing a virtual echo using the echo generated from a short pulse transmission. Moreover by subtracting from this virtual echo the one generated from a longer pulse transmission, it is possible to fully suppress the echo from linear scatterers, while for non-linear scatterers, a signal will remain, allowing classical agent detection. Simulations of a single moving microbubble and a moving linear scatterer subject to these pulses show that when the virtual echo and the long pulse echo are used to perform pulsed Doppler, the power Doppler spectrum allows separation of linear and non-linear moving scattering. Similar results are obtained on experimental data acquired on a flow containing either microbubble contrast agents or linear blood mimicking fluid. This new Doppler method constitutes an alternative to Pulse Inversion Doppler and preliminary results suggest that similar dual band spectrums could be obtained by the combination of any non-linear detection technique with Doppler demodulation.

  11. UWB delay and multiply receiver

    SciTech Connect

    Dallum, Gregory E.; Pratt, Garth C.; Haugen, Peter C.; Romero, Carlos E.

    2013-09-10

    An ultra-wideband (UWB) delay and multiply receiver is formed of a receive antenna; a variable gain attenuator connected to the receive antenna; a signal splitter connected to the variable gain attenuator; a multiplier having one input connected to an undelayed signal from the signal splitter and another input connected to a delayed signal from the signal splitter, the delay between the splitter signals being equal to the spacing between pulses from a transmitter whose pulses are being received by the receive antenna; a peak detection circuit connected to the output of the multiplier and connected to the variable gain attenuator to control the variable gain attenuator to maintain a constant amplitude output from the multiplier; and a digital output circuit connected to the output of the multiplier.

  12. Whole Number Subtraction -- An Analysis.

    ERIC Educational Resources Information Center

    Gilpin, John B.

    This document is intended as a resource for persons using, designing, or evaluating instructional materials in whole number subtraction. Its purpose is to provide conceptual machinery: (1) for describing/specifying subtraction tests and exercises and (2) for formulating related questions and conjectures. It is mainly a logical analysis subject to…

  13. Optical Sidebands Multiplier

    NASA Technical Reports Server (NTRS)

    Strekalov, Dmitry V.; Yu, Nan

    2010-01-01

    Optical sidebands have been generated with relative frequency tens to hundreds of GHz by using optical sidebands that are generated in a cascade process in high-quality optical resonators with Kerr nonlinearity, such as whispering gallery mode (WGM) resonators. For this purpose, the WGM resonator needs to be optically pumped at two frequencies matching its resonances. These two optical components can be one or several free spectral ranges (FSRs), equal to approximately 12 GHz, in this example, apart from each other, and can be easily derived from a monochromatic pump with an ordinary EOM (electro-optic modulation) operating at half the FSR frequency. With sufficient nonlinearity, an optical cascade process will convert the two pump frequencies into a comb-like structure extending many FSRs around the carrier frequency. This has a demonstratively efficient frequency conversion of this type with only a few milliwatt optical pump power. The concept of using Kerr nonlinearity in a resonator for non-degenerate wave mixing has been discussed before, but it was a common belief that this was a weak process requiring very high peak powers to be observable. It was not thought possible for this approach to compete with electro-optical modulators in CW applications, especially those at lower optical powers. By using the high-Q WGM resonators, the effective Kerr nonlinearity can be made so high that, using even weak seeding bands available from a conventional EOM, one can effectively multiply the optical sidebands, extending them into an otherwise inaccessible frequency range.

  14. Inverse reference in subtraction performance: an analysis from arithmetic word problems.

    PubMed

    Orrantia, Josetxu; Rodríguez, Laura; Múñez, David; Vicente, Santiago

    2012-01-01

    Studies of elementary calculation have shown that adults solve basic subtraction problems faster with problems presented in addition format (e.g., 6 ± = 13) than in standard subtraction format (e.g., 13 - 6 = ). Therefore, it is considered that adults solve subtraction problems by reference to the inverse operation (e.g., for 13 - 6 = 7, "I know that 13 is 6 + 7") because presenting the subtraction problem in addition format does not require the mental rearrangement of the problem elements into the addition format. In two experiments, we examine whether adults' use of addition to solve subtractions is modulated by the arrangement of minuend and subtrahend, regardless of format. To this end, we used arithmetic word problems since single-digit problems in subtraction format would not allow the subtrahend to appear before the minuend. In Experiment 1, subtractions were presented by arranging minuend and subtrahend according to previous research. In Experiment 2, operands were reversed. The overall results showed that participants benefited from word problems where the subtrahend appears before the minuend, including subtractions in standard subtraction format. These findings add to a growing body of literature that emphasizes the role of inverse reference in adults' performance on subtractions.

  15. ADD: How Does It Add Up in the Classroom?

    ERIC Educational Resources Information Center

    Sumpter, R. David; Kidd, Libby

    1998-01-01

    Gives a short history of attention-deficit disorder (ADD), describes characteristics of ADD, discusses a four-step plan for identification of ADD, and presents four types of management techniques: medical, environmental, classroom activity, and behavioral management. Stresses importance of cooperation and communication among teacher, parent, and…

  16. NULL convention floating point multiplier.

    PubMed

    Albert, Anitha Juliette; Ramachandran, Seshasayanan

    2015-01-01

    Floating point multiplication is a critical part in high dynamic range and computational intensive digital signal processing applications which require high precision and low power. This paper presents the design of an IEEE 754 single precision floating point multiplier using asynchronous NULL convention logic paradigm. Rounding has not been implemented to suit high precision applications. The novelty of the research is that it is the first ever NULL convention logic multiplier, designed to perform floating point multiplication. The proposed multiplier offers substantial decrease in power consumption when compared with its synchronous version. Performance attributes of the NULL convention logic floating point multiplier, obtained from Xilinx simulation and Cadence, are compared with its equivalent synchronous implementation.

  17. NULL Convention Floating Point Multiplier

    PubMed Central

    Ramachandran, Seshasayanan

    2015-01-01

    Floating point multiplication is a critical part in high dynamic range and computational intensive digital signal processing applications which require high precision and low power. This paper presents the design of an IEEE 754 single precision floating point multiplier using asynchronous NULL convention logic paradigm. Rounding has not been implemented to suit high precision applications. The novelty of the research is that it is the first ever NULL convention logic multiplier, designed to perform floating point multiplication. The proposed multiplier offers substantial decrease in power consumption when compared with its synchronous version. Performance attributes of the NULL convention logic floating point multiplier, obtained from Xilinx simulation and Cadence, are compared with its equivalent synchronous implementation. PMID:25879069

  18. Effective switching frequency multiplier inverter

    DOEpatents

    Su, Gui-Jia; Peng, Fang Z.

    2007-08-07

    A switching frequency multiplier inverter for low inductance machines that uses parallel connection of switches and each switch is independently controlled according to a pulse width modulation scheme. The effective switching frequency is multiplied by the number of switches connected in parallel while each individual switch operates within its limit of switching frequency. This technique can also be used for other power converters such as DC/DC, AC/DC converters.

  19. Microwave Frequency Multiplier

    NASA Astrophysics Data System (ADS)

    Velazco, J. E.

    2017-02-01

    High-power microwave radiation is used in the Deep Space Network (DSN) and Goldstone Solar System Radar (GSSR) for uplink communications with spacecraft and for monitoring asteroids and space debris, respectively. Intense X-band (7.1 to 8.6 GHz) microwave signals are produced for these applications via klystron and traveling-wave microwave vacuum tubes. In order to achieve higher data rate communications with spacecraft, the DSN is planning to gradually furnish several of its deep space stations with uplink systems that employ Ka-band (34-GHz) radiation. Also, the next generation of planetary radar, such as Ka-Band Objects Observation and Monitoring (KaBOOM), is considering frequencies in the Ka-band range (34 to 36 GHz) in order to achieve higher target resolution. Current commercial Ka-band sources are limited to power levels that range from hundreds of watts up to a kilowatt and, at the high-power end, tend to suffer from poor reliability. In either case, there is a clear need for stable Ka-band sources that can produce kilowatts of power with high reliability. In this article, we present a new concept for high-power, high-frequency generation (including Ka-band) that we refer to as the microwave frequency multiplier (MFM). The MFM is a two-cavity vacuum tube concept where low-frequency (2 to 8 GHz) power is fed into the input cavity to modulate and accelerate an electron beam. In the second cavity, the modulated electron beam excites and amplifies high-power microwaves at a frequency that is a multiple integer of the input cavity's frequency. Frequency multiplication factors in the 4 to 10 range are being considered for the current application, although higher multiplication factors are feasible. This novel beam-wave interaction allows the MFM to produce high-power, high-frequency radiation with high efficiency. A key feature of the MFM is that it uses significantly larger cavities than its klystron counterparts, thus greatly reducing power density and arcing

  20. Tumor volume, luxury perfusion, and regional blood volume changes in man visualized by subtraction computerized tomography.

    PubMed

    Penn, R D; Walser, R; Kurtz, D; Ackerman, L

    1976-04-01

    Computer and photographic methods for producing subtractions of computerized axial tomographic (CAT) scans have been developed. By subtracting point for point a normal scan from one taken after intravenous infusion of contrast material, a picture of the contrast in the cerebral vessels is created. By this method, tumor size and degree of vascularity may be assessed. Furthermore, abnormalities in perfusion and changes in blood volume due to mass effects and edema may be detected. Subtracting scans should add to the diagnostic potential of CAT and provide a noninvasive way to study vascular changes in cerebral disease.

  1. Bandpass x-ray diode and x-ray multiplier detector

    DOEpatents

    Wang, C.L.

    1982-09-27

    An absorption-edge of an x-ray absorption filter and a quantum jump of a photocathode determine the bandpass characteristics of an x-ray diode detector. An anode, which collects the photoelectrons emitted by the photocathode, has enhanced amplification provided by photoelectron-multiplying means which include dynodes or a microchannel-plate electron-multiplier. Suppression of undesired high frequency response for a bandpass x-ray diode is provided by subtracting a signal representative of energies above the passband from a signal representative of the overall response of the bandpass diode.

  2. Color Addition and Subtraction Apps

    NASA Astrophysics Data System (ADS)

    Ruiz, Frances; Ruiz, Michael J.

    2015-10-01

    Color addition and subtraction apps in HTML5 have been developed for students as an online hands-on experience so that they can more easily master principles introduced through traditional classroom demonstrations. The evolution of the additive RGB color model is traced through the early IBM color adapters so that students can proceed step by step in understanding mathematical representations of RGB color. Finally, color addition and subtraction are presented for the X11 colors from web design to illustrate yet another real-life application of color mixing.

  3. ADD: Does It Really Exist?

    ERIC Educational Resources Information Center

    Armstrong, Thomas

    1996-01-01

    Questions the existence of attention deficit disorder (ADD), a commonly diagnosed "disease" based on behavioral characteristics. There may be no medical or physiological basis for ADD. The National Association of School Psychologists deplores labeling children and creating categories of exclusion. Instead, educators should respond to individual…

  4. Color Addition and Subtraction Apps

    ERIC Educational Resources Information Center

    Ruiz, Frances; Ruiz, Michael J.

    2015-01-01

    Color addition and subtraction apps in HTML5 have been developed for students as an online hands-on experience so that they can more easily master principles introduced through traditional classroom demonstrations. The evolution of the additive RGB color model is traced through the early IBM color adapters so that students can proceed step by step…

  5. "Subtractive" Bilingualism in Northern Belize.

    ERIC Educational Resources Information Center

    Rubinstein, Robert A.

    "Subtractive" bilingualism in Northern Belize is analyzed based on an extension of a model by Wallace Lambert. The impact of English language instruction on Spanish speaking children in Corozal Town, the northernmost urban center in the British colony of Belize, Central America, is described. This description extends an earlier account…

  6. Fostering First Graders' Fluency with Basic Subtraction and Larger Addition Combinations via Computer-Assisted Instruction

    ERIC Educational Resources Information Center

    Baroody, Arthur J.; Purpura, David J.; Eiland, Michael D.; Reid, Erin E.

    2014-01-01

    Achieving fluency with basic subtraction and add-with-8 or -9 combinations is difficult for primary grade children. A 9-month training experiment entailed evaluating the efficacy of software designed to promote such fluency via guided learning of reasoning strategies. Seventy-five eligible first graders were randomly assigned to one of three…

  7. Switched-Capacitor Voltage Multiplier

    NASA Technical Reports Server (NTRS)

    Sridharan, Govind

    1991-01-01

    Dc-to-dc power converter multiplies input supply potential by factor of nearly 40. Design does not make use of transformers or inductors but effects voltage boost-up by capacitive energy transfer. Circuit primarily made up of banks of capacitors, connected by network of integrated-circuit relays. Converter functionally linear voltage amplifier with fixed gain figure. Bipolar in operation. Output fully floating, and excellent dc isolation between input and output terminals.

  8. The multipliers of multiple trigonometric Fourier series

    NASA Astrophysics Data System (ADS)

    Ydyrys, Aizhan; Sarybekova, Lyazzat; Tleukhanova, Nazerke

    2016-11-01

    We study the multipliers of multiple Fourier series for a regular system on anisotropic Lorentz spaces. In particular, the sufficient conditions for a sequence of complex numbers {λk}k∈Zn in order to make it a multiplier of multiple trigonometric Fourier series from Lp[0; 1]n to Lq[0; 1]n , p > q. These conditions include conditions Lizorkin theorem on multipliers.

  9. Planar diode multiplier chains for THz spectroscopy

    NASA Technical Reports Server (NTRS)

    Maiwald, Frank W.; Drouin, Brian J.; Pearson, John C.; Mehdi, Imran; Lewena, Frank; Endres, Christian; Winnewisser, Gisbert

    2005-01-01

    High-resolution laboratory spectroscopy is utilized as a diagnostic tool to determine noise and harmonic content of balanced [9]-[11] and unbalanced [12]-[14] multiplier designs. Balanced multiplier designs suppress unintended harmonics more than -20dB. Much smaller values were measured on unbalanced multipliers.

  10. Preschoolers' Understanding of Subtraction-Related Principles

    ERIC Educational Resources Information Center

    Baroody, Arthur J.; Lai, Meng-lung; Li, Xia; Baroody, Alison E.

    2009-01-01

    Little research has focused on an informal understanding of subtractive negation (e.g., 3 - 3 = 0) and subtractive identity (e.g., 3 - 0 = 3). Previous research indicates that preschoolers may have a fragile (i.e., unreliable or localized) understanding of the addition-subtraction inverse principle (e.g., 2 + 1 - 1 = 2). Recognition of a small…

  11. Sky subtraction with fiber spectrographs

    NASA Astrophysics Data System (ADS)

    Lissandrini, C.; Cristiani, S.; La Franca, F.

    1994-11-01

    The sky-subtraction performance of multifiber spectrographs is discussed, analyzing in detail the case of the OPTOPUS system at the 3.6-m European Space Observatory (ESO) telescope at La Silla. A standard technique, based on flat fields obtained with a uniformly illuminated screen on the dome, provides poor results. A new method has been developed, using the (O I) emission line at 5577 A as a calibrator of the fiber transmittance, taking into account the diffuse light and the influence of each fiber on the adjacent ones, and correcting for the effects of the image distortions on the sky sampling. In this way the accuracy of the sky subtraction improves from 2%-8% to 1.3%-1.6%.

  12. Children's Use of Subtraction by Addition on Large Single-Digit Subtractions

    ERIC Educational Resources Information Center

    Peters, Greet; De Smedt, Bert; Torbeyns, Joke; Ghesquiere, Pol; Verschaffel, Lieven

    2012-01-01

    Subtractions of the type M - S = ? can be solved by various strategies, including subtraction by addition. In this study, we investigated children's use of subtraction by addition by means of reaction time analyses. We presented 106 third to sixth graders with 32 large non-tie single-digit problems in both subtraction (12 - 9 = .) and addition…

  13. Canonical forms of unconditionally convergent multipliers.

    PubMed

    Stoeva, D T; Balazs, P

    2013-03-01

    Multipliers are operators that combine (frame-like) analysis, a multiplication with a fixed sequence, called the symbol, and synthesis. They are very interesting mathematical objects that also have a lot of applications for example in acoustical signal processing. It is known that bounded symbols and Bessel sequences guarantee unconditional convergence. In this paper we investigate necessary and equivalent conditions for the unconditional convergence of multipliers. In particular, we show that, under mild conditions, unconditionally convergent multipliers can be transformed by shifting weights between symbol and sequence, into multipliers with symbol (1) and Bessel sequences (called multipliers in canonical form).

  14. Add and Subtract: Dual Enrollment as a State Strategy to Increase Postsecondary Success for Underrepresented Students

    ERIC Educational Resources Information Center

    Hoffman, Nancy

    2005-01-01

    Dual enrollment--the arrangements by which high school students take college courses during the junior and senior year--is a promising "next best thing" for states wishing to increase the number of underrepresented students gaining a postsecondary credential. Dual enrollment also has the potential to save money for families and taxpayers…

  15. Digital subtraction angiography in children

    SciTech Connect

    Wagner, M.L.; Singleton, E.B.; Egan, M.E.

    1983-01-01

    Preliminary results with digital subtraction angiography in infants and children have shown this to be an excellent screening procedure and often diagnostic. The examination can be performed satisfactorily on outpatients. Sixty patients have undergone this examination for evaluation of suspected abnormalities of the aortic arch and its branches, intracranial arteries, pulmonary arteries, abdominal aorta and its branches, and peripheral vessels. Adequate sedation is mandatory to prevent motion artifacts. While the literature reports increasing use of central venous catheters for delivery of contrast material, the use of short catheters placed in an antecubital vein is satisfactory for the pediatric patient. Techniques of the procedures are described along with seven appropriate case examples.

  16. High frequency capacitor-diode voltage multiplier dc-dc converter development

    NASA Technical Reports Server (NTRS)

    Kisch, J. J.; Martinelli, R. M.

    1977-01-01

    A power conditioner was developed which used a capacitor diode voltage multiplier to provide a high voltage without the use of a step-up transformer. The power conditioner delivered 1200 Vdc at 100 watts and was operated from a 120 Vdc line. The efficiency was in excess of 90 percent. The component weight was 197 grams. A modified boost-add circuit was used for the regulation. A short circuit protection circuit was used which turns off the drive circuit upon a fault condition, and recovers within 5 ms after removal of the short. High energy density polysulfone capacitors and high speed diodes were used in the multiplier circuit.

  17. A CMOS floating point multiplier

    NASA Astrophysics Data System (ADS)

    Uya, M.; Kaneko, K.; Yasui, J.

    1984-10-01

    This paper describes a 32-bit CMOS floating point multiplier. The chip can perform 32-bit floating point multiplication (based on the proposed IEEE Standard format) and 24-bit fixed point multiplication (two's complement format) in less than 78.7 and 71.1 ns, respectively, and the typical power dissipation is 195 mW at 10 million operations per second. High-speed multiplication techniques - a modified Booth's allgorithm, a carry save adder scheme, a high-speed CMOS full adder, and a modified carry select adder - are used to achieve the above high performance. The chip is designed for compatibility with 16-bit microcomputer systems, and is fabricated in 2 micron n-well CMOS technology; it contains about 23000 transistors of 5.75 x 5.67 sq mm in size.

  18. Contexts for Column Addition and Subtraction

    ERIC Educational Resources Information Center

    Lopez Fernandez, Jorge M.; Velazquez Estrella, Aileen

    2011-01-01

    In this article, the authors discuss their approach to column addition and subtraction algorithms. Adapting an original idea of Paul Cobb and Erna Yackel's from "A Contextual Investigation of Three-Digit Addition and Subtraction" related to packing and unpacking candy in a candy factory, the authors provided an analogous context by…

  19. Addition and Subtraction, and Algorithms in General

    ERIC Educational Resources Information Center

    Fielker, David

    2007-01-01

    The juxtaposition of articles by Ian Thompson and Ian Sugarman in "MT202" on addition and subtraction respectively engendered some bemused thoughts in this author, who for some years has been sheltered from controversy by retirement. In this article, Fielker shares some thoughts on addition and subtraction raised by Thompson and Sugarman in their…

  20. Digital subtraction angiography of the heart and lungs

    SciTech Connect

    Moodie, D.S.; Yiannikas, J.

    1986-01-01

    This book contains 12 chapters. Some of the chapter titles are: Physical Principles of Cardiac Digital Subtraction Angiography, The Use of Intravenous Digital Subtraction Angiography in Evaluating Patients with Complex Congenital Heart Disease, Exercise Intravenous Digital Subtraction Angiograpny, Cardiomyopathic and Cardiac Neoplastic Disease, Digital Subtraction Angiography in the Catheterization Laboratory, and Cardiac Digital Subtraction Angiography - Future Directions.

  1. A geometric approach to spectral subtraction

    PubMed Central

    Lu, Yang; Loizou, Philipos C.

    2008-01-01

    The traditional power spectral subtraction algorithm is computationally simple to implement but suffers from musical noise distortion. In addition, the subtractive rules are based on incorrect assumptions about the cross terms being zero. A new geometric approach to spectral subtraction is proposed in the present paper that addresses these shortcomings of the spectral subtraction algorithm. A method for estimating the cross terms involving the phase differences between the noisy (and clean) signals and noise is proposed. Analysis of the gain function of the proposed algorithm indicated that it possesses similar properties as the traditional MMSE algorithm. Objective evaluation of the proposed algorithm showed that it performed significantly better than the traditional spectral subtractive algorithm. Informal listening tests revealed that the proposed algorithm had no audible musical noise. PMID:19122867

  2. Keynesian multiplier versus velocity of money

    NASA Astrophysics Data System (ADS)

    Wang, Yougui; Xu, Yan; Liu, Li

    2010-08-01

    In this paper we present the relation between Keynesian multiplier and the velocity of money circulation in a money exchange model. For this purpose we modify the original exchange model by constructing the interrelation between income and expenditure. The random exchange yields an agent's income, which along with the amount of money he processed determines his expenditure. In this interactive process, both the circulation of money and Keynesian multiplier effect can be formulated. The equilibrium values of Keynesian multiplier are demonstrated to be closely related to the velocity of money. Thus the impacts of macroeconomic policies on aggregate income can be understood by concentrating solely on the variations of money circulation.

  3. Serial multiplier arrays for parallel computation

    NASA Technical Reports Server (NTRS)

    Winters, Kel

    1990-01-01

    Arrays of systolic serial-parallel multiplier elements are proposed as an alternative to conventional SIMD mesh serial adder arrays for applications that are multiplication intensive and require few stored operands. The design and operation of a number of multiplier and array configurations featuring locality of connection, modularity, and regularity of structure are discussed. A design methodology combining top-down and bottom-up techniques is described to facilitate development of custom high-performance CMOS multiplier element arrays as well as rapid synthesis of simulation models and semicustom prototype CMOS components. Finally, a differential version of NORA dynamic circuits requiring a single-phase uncomplemented clock signal introduced for this application.

  4. Entanglement entropy of subtracted geometry black holes

    NASA Astrophysics Data System (ADS)

    Cvetič, Mirjam; Saleem, Zain H.; Satz, Alejandro

    2014-09-01

    We compute the entanglement entropy of minimally coupled scalar fields on subtracted geometry black hole backgrounds, focusing on the logarithmic corrections. We notice that matching between the entanglement entropy of original black holes and their subtracted counterparts is only at the order of the area term. The logarithmic correction term is not only different but also, in general, changes sign in the subtracted case. We apply Harrison transformations to the original black holes and find out the choice of the Harrison parameters for which the logarithmic corrections vanish.

  5. Multipliers for continuous frames in Hilbert spaces

    NASA Astrophysics Data System (ADS)

    Balazs, P.; Bayer, D.; Rahimi, A.

    2012-06-01

    In this paper, we examine the general theory of continuous frame multipliers in Hilbert space. These operators are a generalization of the widely used notion of (discrete) frame multipliers. Well-known examples include anti-Wick operators, STFT multipliers or Calderón-Toeplitz operators. Due to the possible peculiarities of the underlying measure spaces, continuous frames do not behave quite as their discrete counterparts. Nonetheless, many results similar to the discrete case are proven for continuous frame multipliers as well, for instance compactness and Schatten-class properties. Furthermore, the concepts of controlled and weighted frames are transferred to the continuous setting. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Coherent states: mathematical and physical aspects’.

  6. Open-loop digital frequency multiplier

    NASA Technical Reports Server (NTRS)

    Moore, R. C.

    1977-01-01

    Monostable multivibrator is implemented by using digital integrated circuits where multiplier constant is too large for conventional phase-locked-loop integrated circuit. A 400 Hz clock is generated by divide-by-N counter from 1 Hz timing reference.

  7. Attention Deficit Disorder (ADD). Digest #445.

    ERIC Educational Resources Information Center

    Scott, Mary E.

    The term "attention deficit disorder" (ADD) is defined, criteria used by the American Psychiatric Association in diagnosing ADD are listed, and possible causes noted. Remediation needs of children with ADD include attention skills, self-esteem, and social skills. Early diagnosis is important, and teachers and parents need to identify…

  8. Fingerprinting ordered diffractions in multiply diffracted waves

    NASA Astrophysics Data System (ADS)

    Meles, Giovanni Angelo; Curtis, Andrew

    2014-09-01

    We show how to `fingerprint' individual diffractors inside an acoustic medium using interrogative wave energy from arrays of sources and receivers. For any recorded multiply diffracted wave observed between any source and any receiver, the set of such fingerprints is sufficient information to identify all diffractors involved in the corresponding diffraction path, and the sequential order in which diffractors are encountered. The method herein thus decomposes complex, multiply diffracted wavefields into constituent, single-diffraction interactions.

  9. Minimal subtraction and momentum subtraction in quantum chromodynamics at two-loop order

    SciTech Connect

    Braaten, E.; Leveille, J.P.

    1981-09-01

    The momentum-subtraction coupling constant ..cap alpha../sub MOM/ yields consistently smaller one-loop corrections to many quantum-chromodynamics (QCD) processes than the minimal-subtraction couplings ..cap alpha../sub MS/ and ..cap alpha../sub M/S. By shifting the renormalization scale ..mu.. of ..cap alpha../sub MS/(..mu..), we obtain a minimal-subtraction coupling with the same small one-loop corrections. It is shown, by studying the effective charges of QCD, that at two-loop order this coupling constant will continue to yield corrections to physical quantities that are comparable to those obtained by momentum subtraction. We also introduce a momentum-subtraction scheme which treats the triple-gluon, quark, and ghost vertices equally at one-loop order and is more convenient for higher-order calculations than the MOM scheme.

  10. Problem of Electromagnetoviscoelasticity for Multiply Connected Plates

    NASA Astrophysics Data System (ADS)

    Kaloerov, S. A.; Samodurov, A. A.

    2015-11-01

    A method for solving the problem of electromagnetoviscoelasticity for multiply connected plates is proposed. The small-parameter method is used to reduce this problem to a recursive sequence of problems of electromagnetoelasticity, which are solved by using complex potentials. A procedure is developed to determine, using complex potentials, approximations of the basic characteristics (stresses, electromagnetic-field strength, electromagnetic-flux density) of the electromagnetoelastic state at any time after application of a load. A plate with an elliptic hole is considered as an example. The variation in the electromagnetoelastic state of the multiply connected plate with time is studied

  11. WIDE BAND REGENERATIVE FREQUENCY DIVIDER AND MULTIPLIER

    DOEpatents

    Laine, E.F.

    1959-11-17

    A regenerative frequency divider and multiplier having wide band input characteristics is presented. The circuit produces output oscillations having frequencies related by a fixed ratio to input oscillations over a wide band of frequencies. In accomplishing this end, the divider-multiplier includes a wide band input circuit coupled by mixer means to a wide band output circuit having a pass band related by a fixed ratio to that of the input circuit. A regenerative feedback circuit derives a fixed frequency ratio feedback signal from the output circuit and applies same to the mixer means in proper phase relation to sustain fixed frequency ratio oscillations in the output circuit.

  12. Magnitude subtraction vs. complex subtraction in dynamic contrast-enhanced 3D-MR angiography: basic experiments and clinical evaluation.

    PubMed

    Naganawa, S; Ito, T; Iwayama, E; Fukatsu, H; Ishiguchi, T; Ishigaki, T; Ichinose, N

    1999-11-01

    Magnitude subtraction and complex subtraction in dynamic contrast-enhanced three-dimensional magnetic resonance (3D-MR) angiography were compared using a phantom and 23 human subjects. In phantom studies, complex subtraction showed far better performance than magnitude subtraction, especially for longer echo times, with thicker slices, and without fat suppression. With complex subtraction, non-fat-suppressed studies showed contrast-to-noise ratios comparable to those in fat-suppressed studies. In human subjects, complex subtraction was superior to magnitude subtraction in 9 subjects, but comparable to magnitude subtraction in 14 subjects. There were no cases in which magnitude subtraction was superior to complex subtraction. Although the differences observed in human studies when complex subtraction was applied with thinner slices, shorter echo times, and the fat-suppression technique were not as pronounced as those seen in phantom studies, complex subtraction should be performed in dynamic contrast-enhanced 3D-MR angiography because there are no drawbacks in complex subtraction. Further research is necessary to assess the feasibility of dynamic contrast-enhanced 3D-MR angiography without fat suppression in human subjects using complex subtraction, as suggested by the results of phantom studies. If it is found to be feasible, dynamic contrast-enhanced 3D-MR angiography without fat suppression using complex subtraction may prove to be a robust technique that eliminates the need for shimming and can reduce the acquisition time. J. Magn. Reson. Imaging 1999;10:813-820.

  13. Inviting Calm Within: ADD, Neurology, and Mindfulness

    ERIC Educational Resources Information Center

    Riner, Phillip S.; Tanase, Madalina

    2014-01-01

    The fourth edition of the "Diagnostic and Statistical Manual of Mental Disorders" ("DSM IV") describes ADD as behaviorally observed impairments in attention, impulsivity, and hyperactivity. Officially known as AD/HD, we use ADD here because we are dealing primarily with attention, organizational, and impulsivity issues. A more…

  14. ADD: Acronym for Any Dysfunction or Difficulty.

    ERIC Educational Resources Information Center

    Goodman, Gay; Poillion, Mary Jo

    1992-01-01

    Review of 48 articles and books on attention deficit disorder (ADD) found a total of 69 characteristics and 38 causes cited, evidencing no clearcut pattern for identifying the condition and little agreement for what causes ADD. The label appears to have limited value for communication, planning, decision making, or research efforts. (Author/DB)

  15. Temperature Effects in Varactors and Multipliers

    NASA Technical Reports Server (NTRS)

    East, J.; Mehdi, Imran

    2001-01-01

    Varactor diode multipliers are a critical part of many THz measurement systems. The power and efficiencies of these devices limit the available power for THz sources. Varactor operation is determined by the physics of the varactor device and a careful doping profile design is needed to optimize the performance. Higher doped devices are limited by junction breakdown and lower doped structures are limited by current saturation. Higher doped structures typically have higher efficiencies and lower doped structures typically have higher powers at the same operating frequency and impedance level. However, the device material properties are also a function of the operating temperature. Recent experimental evidence has shown that the power output of a multiplier can be improved by cooling the device. We have used a particle Monte Carlo simulation to investigate the temperature dependent velocity vs. electric field in GaAs. This information was then included in a nonlinear device circuit simulator to predict multiplier performance for various temperatures and device designs. This paper will describe the results of this analysis of temperature dependent multiplier operation.

  16. Strategies in Subtraction Problem Solving in Children

    ERIC Educational Resources Information Center

    Barrouillet, Pierre; Mignon, Mathilde; Thevenot, Catherine

    2008-01-01

    The aim of this study was to investigate the strategies used by third graders in solving the 81 elementary subtractions that are the inverses of the one-digit additions with addends from 1 to 9 recently studied by Barrouillet and Lepine. Although the pattern of relationship between individual differences in working memory, on the one hand, and…

  17. Simple circuit performs binary addition and subtraction

    NASA Technical Reports Server (NTRS)

    Cliff, R. A.; Schaefer, D. H.

    1965-01-01

    Ripple adder reduces the number of logic circuits required to preform binary addition and subtraction. The adder uses dual input and delayed output flip-flops in one register. The contents of this register are summed with those of a standard register through conventional AND/gates.

  18. Polygon Subtraction in 2 or 3 Dimensions

    SciTech Connect

    Wilson, John E.

    2013-10-01

    When searching for computer code to perform the ubiquitous task of subtracting one polygon from another, it is difficult to find real examples and detailed explanations. This paper outlines the step-by-step process necessary to accomplish this basic task.

  19. Children's Understanding of Addition and Subtraction Concepts

    ERIC Educational Resources Information Center

    Robinson, Katherine M.; Dube, Adam K.

    2009-01-01

    After the onset of formal schooling, little is known about the development of children's understanding of the arithmetic concepts of inversion and associativity. On problems of the form a+b-b (e.g., 3+26-26), if children understand the inversion concept (i.e., that addition and subtraction are inverse operations), then no calculations are needed…

  20. An experimental implementation of chemical subtraction.

    PubMed

    Chen, Shao-Nong; Turner, Allison; Jaki, Birgit U; Nikolic, Dejan; van Breemen, Richard B; Friesen, J Brent; Pauli, Guido F

    2008-03-13

    A preparative analytical method was developed to selectively remove ("chemically subtract") a single compound from a complex mixture, such as a natural extract or fraction, in a single step. The proof of concept is demonstrated by the removal of pure benzoic acid (BA) from cranberry (Vaccinium macrocarpon Ait.) juice fractions that exhibit anti-adhesive effects versus uropathogenic Escherichia coli. Chemical subtraction of BA, representing a major constituent of the fractions, eliminates the potential in vitro interference of the bacteriostatic effect of BA on the E. coli anti-adherence action measured in bioassays. Upon BA removal, the anti-adherent activity of the fraction was fully retained, 36% inhibition of adherence in the parent fraction at 100mug/mL increased to 58% in the BA-free active fraction. The method employs countercurrent chromatography (CCC) and operates loss-free for both the subtracted and the retained portions as only liquid-liquid partitioning is involved. While the high purity (97.47% by quantitative (1)H NMR) of the subtracted BA confirms the selectivity of the method, one minor impurity was determined to be scopoletin by HR-ESI-MS and (q)HNMR and represents the first coumarin reported from cranberries. A general concept for the selective removal of phytoconstituents by CCC is presented, which has potential broad applicability in the biological evaluation of medicinal plant extracts and complex pharmaceutical preparations.

  1. Diagnosis of Subtraction Bugs Using Bayesian Networks

    ERIC Educational Resources Information Center

    Lee, Jihyun; Corter, James E.

    2011-01-01

    Diagnosis of misconceptions or "bugs" in procedural skills is difficult because of their unstable nature. This study addresses this problem by proposing and evaluating a probability-based approach to the diagnosis of bugs in children's multicolumn subtraction performance using Bayesian networks. This approach assumes a causal network relating…

  2. Children's Profiles of Addition and Subtraction Understanding

    ERIC Educational Resources Information Center

    Canobi, Katherine H.

    2005-01-01

    The current research explored children's ability to recognize and explain different concepts both with and without reference to physical objects so as to provide insight into the development of children's addition and subtraction understanding. In Study 1, 72 7- to 9-year-olds judged and explained a puppet's activities involving three conceptual…

  3. Transactional Algorithm for Subtracting Fractions: Go Shopping

    ERIC Educational Resources Information Center

    Pinckard, James Seishin

    2009-01-01

    The purpose of this quasi-experimental research study was to examine the effects of an alternative or transactional algorithm for subtracting mixed numbers within the middle school setting. Initial data were gathered from the student achievement of four mathematics teachers at three different school sites. The results indicated students who…

  4. Congruence of Behavioral Symptomatology in Children with ADD/H, ADD/WO, and Learning Disabilities.

    ERIC Educational Resources Information Center

    Stanford, Lisa D.; Hynd, George W.

    1994-01-01

    This study compared parent and teacher behavioral ratings for 77 children (ages 5-16) diagnosed as having attention deficit disorder with hyperactivity (ADD/H), attention deficit disorder without hyperactivity (ADD/WO), or learning disabilities (LD). ADD/WO and LD children were rated similarly on symptoms of withdrawal and impulsivity but differed…

  5. 76 FR 49508 - ``Add Us In'' Initiative

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Office of Disability Employment Program ``Add Us In'' Initiative AGENCY: Office of Disability Employment Policy, Department of Labor. ACTION: Correction to the Funding Opportunity Number and Closing...

  6. Instabilities in a Layer-Multiplying Device

    NASA Astrophysics Data System (ADS)

    Sollogoub, Cyrille; Grandmontagne, Anne; Guinault, Alain

    2011-01-01

    The application of a layer-multiplying device to coextrusion has resulted in a process, called microlayer coextrusion, producing films with ten to thousands of layers of two different polymers. It was shown that this device is quite versatile and can be used to produce new layered systems with improved mechanical, optical, electrical and barrier properties. However, instabilities may occur in the feedblock and/or the layer multiplying unit, affecting the uniformity and the continuity of the created layers. Those instabilities have been widely studied for classical systems with three to five layer structures, while very few studies deal with microlayer coextrusion process. The aim of this paper is to study the flow instabilities in multilayered films. In particular, the role of polymer properties and the effect of some parameters, such as the viscosity ratio, will be investigated.

  7. Low-Jitter Digital Rate Multiplier

    NASA Technical Reports Server (NTRS)

    Katz, Richard B.; Rakow, Glenn P.

    1993-01-01

    Jitter in digital rate multiplier reduced by improved method involving use of two slightly different minor clock periods. Original application to divide measured period of spin of spacecraft into large number of equal subintervals, by counting cycles of master oscillator running at high frequency. Method also used to reduce jitter in other situations necessary to generate equal subintervals from synchronizing clock signal of arbitrary period. Particularly valuable in situations where synchronizing signals lost temporarily and where drift in analog circuit unacceptable.

  8. Lagrange multipliers in theories of gravitation

    SciTech Connect

    Kichenassamy, S.

    1986-05-01

    In gravitatinal theories, P-italic-variation (independepent variation of metric and connection) and H-variation (variation of the metric alone) may be reconciled through C-italic-variation (use of Lagrange multipliers ..lambda.. in P-italic-variation). We extend C-italic-variation to fields coupled with gravitational field and elucidate the cases of vanishing ..lambda... We show that the interpretation of ..lambda.. as constraint reaction forces sheds new light on the structure of these theories; we are thus led to question the necessary of relating torsion to spin, and as an alternative to the theory of Dirac particles in Einstein-Cartan space-time, we propose in a Lorentzian space-time a theory in which Lagrange multipliers corresponding to the vanishing of torsion lead to the symmetrization of canonical energy-momentum tensor and avoid the Heisenberg-Pauli-type terms. Lagrange multipliers also serve to reduce the fourth-order differential equations of gravitational quadratic Lagrangians to second-order ones with additional field variables (a scalar P-italic and a traceless tensor P-italic-tilde/sub i//sub j/); this reduction helps to make precise the compatibility of these theories with General Relativity. Simple derivations are also given for Chern and Euler characteristics c-italic/sub 2/ and /sub Chi//sub 2/, and for other identities.

  9. Yeast peroxisomes multiply by growth and division.

    PubMed

    Motley, Alison M; Hettema, Ewald H

    2007-07-30

    Peroxisomes can arise de novo from the endoplasmic reticulum (ER) via a maturation process. Peroxisomes can also multiply by fission. We have investigated how these modes of multiplication contribute to peroxisome numbers in Saccharomyces cerevisiae and the role of the dynamin-related proteins (Drps) in these processes. We have developed pulse-chase and mating assays to follow the fate of existing peroxisomes, de novo-formed peroxisomes, and ER-derived preperoxisomal structures. We find that in wild-type (WT) cells, peroxisomes multiply by fission and do not form de novo. A marker for the maturation pathway, Pex3-GFP, is delivered from the ER to existing peroxisomes. Strikingly, cells lacking peroxisomes as a result of a segregation defect do form peroxisomes de novo. This process is slower than peroxisome multiplication in WT cells and is Drp independent. In contrast, peroxisome fission is Drp dependent. Our results show that peroxisomes multiply by growth and division under our assay conditions. We conclude that the ER to peroxisome pathway functions to supply existing peroxisomes with essential membrane constituents.

  10. Automobile Industry Retail Price Equivalent and Indirect Cost Multipliers

    EPA Science Inventory

    This report develops a modified multiplier, referred to as an indirect cost (IC) multiplier, which specifically evaluates the components of indirect costs that are likely to be affected by vehicle modifications associated with environmental regulation. A range of IC multipliers a...

  11. Liquid-Crystal-Television Image Subtracters

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin; Liu, Hua-Kuang

    1988-01-01

    Two image-subtraction systems from output images that show differences between input images of two objects. First: differences appear as bright regions in otherwise dark output image. Second: differences and similarities shown by colors. All parts of two images processed simultaneously by optical components only; digital electronic processing of data not required. Concept offers potential for rapid, inexpensive comparison of images in such applications as automatic inspection, medical diagnosis, and robotic vision.

  12. Subtractive Structural Modification of Morpho Butterfly Wings.

    PubMed

    Shen, Qingchen; He, Jiaqing; Ni, Mengtian; Song, Chengyi; Zhou, Lingye; Hu, Hang; Zhang, Ruoxi; Luo, Zhen; Wang, Ge; Tao, Peng; Deng, Tao; Shang, Wen

    2015-11-11

    Different from studies of butterfly wings through additive modification, this work for the first time studies the property change of butterfly wings through subtractive modification using oxygen plasma etching. The controlled modification of butterfly wings through such subtractive process results in gradual change of the optical properties, and helps the further understanding of structural optimization through natural evolution. The brilliant color of Morpho butterfly wings is originated from the hierarchical nanostructure on the wing scales. Such nanoarchitecture has attracted a lot of research effort, including the study of its optical properties, its potential use in sensing and infrared imaging, and also the use of such structure as template for the fabrication of high-performance photocatalytic materials. The controlled subtractive processes provide a new path to modify such nanoarchitecture and its optical property. Distinct from previous studies on the optical property of the Morpho wing structure, this study provides additional experimental evidence for the origination of the optical property of the natural butterfly wing scales. The study also offers a facile approach to generate new 3D nanostructures using butterfly wings as the templates and may lead to simpler structure models for large-scale man-made structures than those offered by original butterfly wings.

  13. Electrical Characterization of Silicon Photo-Multipliers

    NASA Astrophysics Data System (ADS)

    Mwathi, John; Woody, Craig; Stoll, Sean

    2014-09-01

    Silicon photo-multipliers (SiPM) also known as Multi-Pixel Photon Counters (MPPC) are single photon sensitive, semiconductor devices built from Avalanche Photo Diodes (APDs) working in the Geiger mode. The SiPM detectors provide an attractive solution for the detection of signals with low numbers of photons and are suitable candidates to replace Vacuum Photo-Multiplier Tubes (PMTs). They offer advantages over both PMTs and the APDs, including compactness, insensitivity to magnetic fields, high gain (105), ability to be operated at moderate bias voltage (normally lower than 100 volts), and excellent timing properties these characteristics make them suitable for applications in several fields of high energy physics and medical imaging. At Brookhaven National Laboratory, silicon photo-multipliers have been suggested as the readout device to be used in the upgraded sPHENIX in the area of high-energy physics calorimetry and future Positron Emission Tomography (PET) medical imaging systems. Despite all these advantages SiPMs have several drawbacks such as crosstalk, after pulse rate and dark-count rate, exposure to radiation damages the detector and greatly affects its efficiency. We characterized SiPMs of different pixel sizes from SensL and Hamamatsu to determine the SiPM's performance and which of these detectors would best be suited for application. We characterized these SiPM samples using lab instruments including a Picometer and a digital oscilloscope. A Lab view program controlling and reading out the Keithley Picometer via an IEEE-GPIB interface was developed to automate the dark current as a function of bias voltage measurement. Silicon photo-multipliers (SiPM) also known as Multi-Pixel Photon Counters (MPPC) are single photon sensitive, semiconductor devices built from Avalanche Photo Diodes (APDs) working in the Geiger mode. The SiPM detectors provide an attractive solution for the detection of signals with low numbers of photons and are suitable candidates

  14. Nonreciprocal photonic crystal add-drop filter

    SciTech Connect

    Tao, Keyu; Xiao, Jun-Jun; Yin, Xiaobo

    2014-11-24

    We present a versatile add-drop integrated photonic filter (ADF) consisting of nonreciprocal waveguides in which the propagation of light is restricted in one predetermined direction. With the bus and add/drop waveguides symmetrically coupled through a cavity, the four-port device allows each individual port to add and/or drop a signal of the same frequency. The scheme is general and we demonstrate the nonreciprocal ADF with magneto-optical photonic crystals. The filter is immune to waveguide defects, allowing straightforward implementation of multi-channel ADFs by cascading the four-port designs. The results should find applications in wavelength-division multiplexing and related integrated photonic techniques.

  15. The association between children's numerical magnitude processing and mental multi-digit subtraction.

    PubMed

    Linsen, Sarah; Verschaffel, Lieven; Reynvoet, Bert; De Smedt, Bert

    2014-01-01

    Children apply various strategies to mentally solve multi-digit subtraction problems and the efficient use of some of them may depend more or less on numerical magnitude processing. For example, the indirect addition strategy (solving 72-67 as "how much do I have to add up to 67 to get 72?"), which is particularly efficient when the two given numbers are close to each other, requires to determine the proximity of these two numbers, a process that may depend on numerical magnitude processing. In the present study, children completed a numerical magnitude comparison task and a number line estimation task, both in a symbolic and nonsymbolic format, to measure their numerical magnitude processing. We administered a multi-digit subtraction task, in which half of the items were specifically designed to elicit indirect addition. Partial correlational analyses, controlling for intellectual ability and motor speed, revealed significant associations between numerical magnitude processing and mental multi-digit subtraction. Additional analyses indicated that numerical magnitude processing was particularly important for those items for which the use of indirect addition is expected to be most efficient. Although this association was observed for both symbolic and nonsymbolic tasks, the strongest associations were found for the symbolic format, and they seemed to be more prominent on numerical magnitude comparison than on number line estimation.

  16. Gas Electron Multiplier Tracking Telescopes for OLYMPUS

    NASA Astrophysics Data System (ADS)

    McMahon, Joshua; Campbell, Miles

    2011-10-01

    The OLYMPUS collaboration is conducting an experiment to measure two-photon contributions to elastic electron scattering. The experiment is taking place at the DORIS storage ring at DESY, Hamburg, Germany using the upgraded BLAST detector from the MIT-Bates Linear Accelerator Center. Gas Electron Multiplier (GEM) telescopes are used to detect scattered leptons at a forward angle to monitor the luminosity. The GEM detectors have been commissioned at the test facility at DESY and were installed along with the main detector in the DORIS storage ring. With the testbeam the performance characteristics such as gain, efficiency, multiplicity, and resolution of the GEMs were studied.

  17. Spectral Multipliers for Schrodinger Operators: 1

    DTIC Science & Technology

    2007-01-18

    harmonic analysis and PDEs. It is closely related to the study of the associated function spaces and Littlewood -Paley theory. Let H = −∆ + V be a...Secondary: 35J10, 35P25, 35Q40. Key words and phrases. spectral multiplier, Schrödinger operator, Littlewood - Paley theory. The author is supported...to the identity, so that ρ ∈ L1(Rn) is positive and decreasing, then sup t>0 |ρt ∗ f(x)| ≤Mf(x) where M denotes the Hardy- Littlewood maximal function

  18. Shift-and-add for astronomical imaging

    NASA Technical Reports Server (NTRS)

    Ribak, Erez; Hege, E. Keith; Strobel, Nicolas V.; Christou, Julian C.

    1989-01-01

    Diffraction-limited astronomical images have been obtained utilizing a variant of the shift-and-add method. It is shown that the matched filter approach for extending the weighted shift-and-add method reduces specklegrams from extended objects and from an object dominated by photon noise. The method is aberration-insensitive and yields very high dynamic range results. The iterative method for arriving at the matched filter does not automatically converge in the case of photon-noisy specklegrams for objects with more than one maximum.

  19. Digital subtraction angiography of the thoracic aorta

    SciTech Connect

    Grossman, L.B.; Buonocore, E.; Modic, M.T.; Meaney, T.F.

    1984-02-01

    Forty-three patients with acquired and congenital abnormalities of the thoracic aorta were studied using digital subtraction angiography (DSA) after an intravenous bolus injection of 40 ml of contrast material. Abnormalities studied included coarctation, pseudocoarctation, Marfan syndrome, cervical aorta, double aortic arch, aneurysm, dissection, and tumor. Twenty-four patients also had conventional angiography. DSA was accurate in 95% of cases; in the other 5%, involving patients with acute type I dissection, the coronary arteries could not be seen. The authors concluded that in 92% of their patients, DSA could have replaced the standard aortogram.

  20. Digital subtraction angiography of the kidney.

    PubMed

    Gattoni, F; Avogadro, A; Baldini, U; Pozzato, C; Bonfanti, M T; Gandini, D; Franch, L; Uslenghi, C

    1988-09-01

    Intravenous and intra-arterial digital subtraction angiography (DSA) was performed in 88 patients: 34 with tumours, 10 with renal trauma, 26 with suspected renovascular hypertension, 6 with vascular impression on the renal pelvis, 8 with nephrolithiasis and 4 with sonographically abnormal kidneys. Venous and arterial DSA always gave diagnostically useful images. Intravenous DSA is valuable in patients with suspected renovascular hypertension or after vascular surgery, percutaneous transluminal angioplasty and transcatheter embolisation. Arterial DSA is preferable to venous DSA in other clinical situations, particularly in the evaluation of renal tumours, and may be recommended in preference to conventional angiography.

  1. Dynamic powerline interference subtraction from biosignals.

    PubMed

    Christov, I I

    2000-01-01

    The performance of a previously developed and widely used method for powerline interference subtraction from the ECG is slightly reduced in the presence of continuous well-expressed EMG noise. Applying automatic adaptation of the 'linearity criterion' value in accordance to the ECG/noise ratio, the best conditions for application of the procedure can be obtained. The proposed method allows for reduction of possible distortions when applied on noise-free ECG and enhances its efficiency in the presence of non-powerline noise. Apart from ECG, it is applicable to impedance-cardiogram, plethysmogram, EEG and other biosignals.

  2. 76 FR 47240 - ``Add Us In'' Initiative

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-04

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Office of Disability Employment Policy ``Add Us In'' Initiative AGENCY: Office of Disability Employment Policy, Department of Labor. Announcement Type: New Notice of Availability of Funds and Solicitation for Grant Applications (SGA) for...

  3. 75 FR 45164 - ``Add Us In'' Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-02

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Office of the Assistant Secretary for Office of Disability Employment Policy ``Add Us In'' Program AGENCY: Office of Disability Employment Policy, Department of Labor. Announcement Type: New Notice of Availability of Funds and Solicitation for...

  4. Shift Would Add Burden on Principals

    ERIC Educational Resources Information Center

    Killion, Joellen

    2004-01-01

    In this article, the author describes how the transition from district-centered to school-based staff development can add to the burden on principals. This column first presents a brief review of the efforts of Braxton Hinsdale, a staff development director who advocated for moving professional development resources from the district level to the…

  5. Selected Perspectives on ADD and ADHD.

    ERIC Educational Resources Information Center

    Porter, Louise

    1997-01-01

    Offers an overview of ADD and ADHD, their causes and long-term prognoses, including the complexities of the conditions, the incomplete knowledge about them, and the difficulties of diagnosis during early childhood. Summarizes assessment and treatment options and concludes that the conditions have so many secondary effects that designing an…

  6. Educational Interventions for Students with ADD.

    ERIC Educational Resources Information Center

    Salend, Spencer J.; Elhoweris, Hala; van Garderen, Delinda

    2003-01-01

    Principles of educational interventions for students with attention deficit disorder (ADD) include: (1) giving complete and thorough directions; (2) individualizing in-class and homework assignments; (3) motivating students; (4) promoting active responding and monitoring understanding; (5) employing content enhancements; (6) offering learning…

  7. A Mathematical Model for Suppression Subtractive Hybridization

    PubMed Central

    Gadgil, Chetan; Rink, Anette; Beattie, Craig

    2002-01-01

    Suppression subtractive hybridization (SSH) is frequently used to unearth differentially expressed genes on a whole-genome scale. Its versatility is based on combining cDNA library subtraction and normalization, which allows the isolation of sequences of varying degrees of abundance and differential expression. SSH is a complex process with many adjustable parameters that affect the outcome of gene isolation.We present a mathematical model of SSH based on DNA hybridization kinetics for assessing the effect of various parameters to facilitate its optimization. We derive an equation for the probability that a particular differentially expressed species is successfully isolated and use this to quantify the effect of the following parameters related to the cDNA sample: (a) mRNA abundance; (b) partial sequence complementarity to other species; and (3) degree of differential expression. We also evaluate the effect of parameters related to the process, including: (a) reaction times; and (b) extent of driver excess used in the two hybridization reactions. The optimum set of process parameters for successful isolation of differentially expressed species depends on transcript abundance. We show that the reaction conditions have a significant effect on the occurrence of false-positives and formulate strategies to isolate specific subsets of differentially expressed genes. We also quantify the effect of non-specific hybridization on the false-positive results and present strategies for spiking cDNA sequences to address this problem. PMID:18629052

  8. Additive and subtractive transparent depth displays

    NASA Astrophysics Data System (ADS)

    Kooi, Frank L.; Toet, Alexander

    2003-09-01

    Image fusion is the generally preferred method to combine two or more images for visual display on a single screen. We demonstrate that perceptual image separation may be preferable over perceptual image fusion for the combined display of enhanced and synthetic imagery. In this context image separation refers to the simultaneous presentation of images on different depth planes of a single display. Image separation allows the user to recognize the source of the information that is displayed. This can be important because synthetic images are more liable to flaws. We have examined methods to optimize perceptual image separation. A true depth difference between enhanced and synthetic imagery works quite well. A standard stereoscopic display based on convergence is less suitable since the two images tend to interfere: the image behind is masked (occluded) by the image in front, which results in poor viewing comfort. This effect places 3D systems based on 3D glasses, as well as most autostereoscopic displays, at a serious disadvantage. A 3D display based on additive or subtractive transparency is acceptable: both the perceptual separation and the viewing comfort are good, but the color of objects depends on the color in the other depth layer(s). A combined additive and subtractive transparent display eliminates this disadvantage and is most suitable for the combined display of enhanced and synthetic imagery. We suggest that the development of such a display system is of a greater practical value than increasing the number of depth planes in autostereoscopic displays.

  9. Children's understanding of addition and subtraction concepts.

    PubMed

    Robinson, Katherine M; Dubé, Adam K

    2009-08-01

    After the onset of formal schooling, little is known about the development of children's understanding of the arithmetic concepts of inversion and associativity. On problems of the form a+b-b (e.g., 3+26-26), if children understand the inversion concept (i.e., that addition and subtraction are inverse operations), then no calculations are needed to solve the problem. On problems of the form a+b-c (e.g., 3+27-23), if children understand the associativity concept (i.e., that the addition and subtraction can be solved in any order), then the second part of the problem can be solved first. Children in Grades 2, 3, and 4 solved both types of problems and then were given a demonstration of how to apply both concepts. Approval of each concept and preference of a conceptual approach versus an algorithmic approach were measured. Few grade differences were found on either task. Conceptual understanding was greater for inversion than for associativity on both tasks. Clusters of participants in all grades showed that some had strong understanding of both concepts, some had strong understanding of the inversion concept only, and others had weak understanding of both concepts. The findings highlight the lack of developmental increases and the large individual differences in conceptual understanding on two arithmetic concepts during the early school years.

  10. Multiplier Accounting of Indian Mining Industry--The Concept

    NASA Astrophysics Data System (ADS)

    Hussain, A.; Karmakar, N. C.

    2015-04-01

    Input-output multipliers are indicators used for predicting the total impact on an economy due to the changes in its industrial demand and output. Also, input-output tables provide detailed dissection of the intermediate transactions in an economy. The aim of the paper is to put forward a basic framework of input-output economics as well as the multiplier concept. The outline of the methodology for calculating the multiplier associated with Indian mining industry is also presented.

  11. Topological Interactions in Multiply Linked DNA Rings

    NASA Astrophysics Data System (ADS)

    Otto, M.; Vilgis, T. A.

    1998-01-01

    The elasticity of DNA catenanes, i.e., multiply linked DNA rings, is investigated using the Gauss invariant as a minimal model for topology conservation. An effective elastic free energy as a function of the distance R between segments located on different rings is obtained. An anharmonic part at large distances, growing as R4, if R>>RG ( RG being the radius of gyration), is found, for R<

  12. Capacitance multiplier and filter synthesizing network

    NASA Technical Reports Server (NTRS)

    Kline, A. J. (Inventor)

    1974-01-01

    A circuit using a differential amplifier multiplies the capacitance of a discrete interating capacitor by (r sub 1 + R sub 2)/R sub 2, where R sub 1 and R sub 2 are values of discrete resistor coupling an input signal e sub 1 of the amplifier inputs. The output e sub 0 of the amplifier is fed back and added to the signal coupled by the resistor R sub 2 to the amplifier through a resistor of value R sub 1. A discrete resistor R sub x may be connected in series for a lag filter, and a discrete resistor may be connected in series with the capacitor for a lead-lag filter. Voltage dividing resistors R sub a and R sub b may be included in the feedback circuit of the amplifier output e sub o to independently adjust the circuit gain e sub i/e sub o.

  13. Analysis of Variance of Multiply Imputed Data.

    PubMed

    van Ginkel, Joost R; Kroonenberg, Pieter M

    2014-01-01

    As a procedure for handling missing data, Multiple imputation consists of estimating the missing data multiple times to create several complete versions of an incomplete data set. All these data sets are analyzed by the same statistical procedure, and the results are pooled for interpretation. So far, no explicit rules for pooling F-tests of (repeated-measures) analysis of variance have been defined. In this paper we outline the appropriate procedure for the results of analysis of variance for multiply imputed data sets. It involves both reformulation of the ANOVA model as a regression model using effect coding of the predictors and applying already existing combination rules for regression models. The proposed procedure is illustrated using three example data sets. The pooled results of these three examples provide plausible F- and p-values.

  14. Four-gate transistor analog multiplier circuit

    NASA Technical Reports Server (NTRS)

    Mojarradi, Mohammad M. (Inventor); Blalock, Benjamin (Inventor); Cristoloveanu, Sorin (Inventor); Chen, Suheng (Inventor); Akarvardar, Kerem (Inventor)

    2011-01-01

    A differential output analog multiplier circuit utilizing four G.sup.4-FETs, each source connected to a current source. The four G.sup.4-FETs may be grouped into two pairs of two G.sup.4-FETs each, where one pair has its drains connected to a load, and the other par has its drains connected to another load. The differential output voltage is taken at the two loads. In one embodiment, for each G.sup.4-FET, the first and second junction gates are each connected together, where a first input voltage is applied to the front gates of each pair, and a second input voltage is applied to the first junction gates of each pair. Other embodiments are described and claimed.

  15. Astronomical Image Subtraction by Cross-Convolution

    NASA Astrophysics Data System (ADS)

    Yuan, Fang; Akerlof, Carl W.

    2008-04-01

    In recent years, there has been a proliferation of wide-field sky surveys to search for a variety of transient objects. Using relatively short focal lengths, the optics of these systems produce undersampled stellar images often marred by a variety of aberrations. As participants in such activities, we have developed a new algorithm for image subtraction that no longer requires high-quality reference images for comparison. The computational efficiency is comparable with similar procedures currently in use. The general technique is cross-convolution: two convolution kernels are generated to make a test image and a reference image separately transform to match as closely as possible. In analogy to the optimization technique for generating smoothing splines, the inclusion of an rms width penalty term constrains the diffusion of stellar images. In addition, by evaluating the convolution kernels on uniformly spaced subimages across the total area, these routines can accommodate point-spread functions that vary considerably across the focal plane.

  16. [Myocardial perfusion imaging by digital subtraction angiography].

    PubMed

    Kadowaki, H; Ishikawa, K; Ogai, T; Katori, R

    1986-03-01

    Several methods of digital subtraction angiography (DSA) were compared to determine which could better visualize regional myocardial perfusion using coronary angiography in seven patients with myocardial infarction, two with angina pectoris and five with normal coronary arteries. Satisfactory DSA was judged to be achieved if the shape of the heart on the mask film was identical to that on the live film and if both films were exactly superimposed. To obtain an identical mask film in the shape of each live film, both films were selected from the following three phases of the cardiac cycle; at the R wave of the electrocardiogram, 100 msec before the R wave, and 200 msec before the R wave. The last two were superior for obtaining mask and live films which were similar in shape, because the cardiac motion in these phases was relatively small. Using these mask and live films, DSA was performed either with the continuous image mode (CI mode) or the time interval difference mode (TID mode). The overall perfusion of contrast medium through the artery to the vein was adequately visualized using the CI mode. Passage of contrast medium through the artery, capillary and vein was visualized at each phase using TID mode. Subtracted images were displayed and photographed, and the density of the contrast medium was adequate to display contour lines as in a relief map. Using this DSA, it was found that regional perfusion of the contrast medium was not always uniform in normal subjects, depending on the typography of the coronary artery.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. An Efficient 16-Bit Multiplier based on Booth Algorithm

    NASA Astrophysics Data System (ADS)

    Khan, M. Zamin Ali; Saleem, Hussain; Afzal, Shiraz; Naseem, Jawed

    2012-11-01

    Multipliers are key components of many high performance systems such as microprocessors, digital signal processors, etc. Optimizing the speed and area of the multiplier is major design issue which is usually conflicting constraint so that improving speed results mostly in bigger areas. A VHDL designed architecture based on booth multiplication algorithm is proposed which not only optimize speed but also efficient on energy use.

  18. Renormalization of quark bilinear operators in a momentum-subtraction scheme with a nonexceptional subtraction point

    SciTech Connect

    Sturm, C.; Soni, A.; Aoki, Y.; Christ, N. H.; Izubuchi, T.; Sachrajda, C. T. C.

    2009-07-01

    We extend the Rome-Southampton regularization independent momentum-subtraction renormalization scheme (RI/MOM) for bilinear operators to one with a nonexceptional, symmetric subtraction point. Two-point Green's functions with the insertion of quark bilinear operators are computed with scalar, pseudoscalar, vector, axial-vector and tensor operators at one-loop order in perturbative QCD. We call this new scheme RI/SMOM, where the S stands for 'symmetric'. Conversion factors are derived, which connect the RI/SMOM scheme and the MS scheme and can be used to convert results obtained in lattice calculations into the MS scheme. Such a symmetric subtraction point involves nonexceptional momenta implying a lattice calculation with substantially suppressed contamination from infrared effects. Further, we find that the size of the one-loop corrections for these infrared improved kinematics is substantially decreased in the case of the pseudoscalar and scalar operator, suggesting a much better behaved perturbative series. Therefore it should allow us to reduce the error in the determination of the quark mass appreciably.

  19. Evolutionary Processes in the Development of Errors in Subtraction Algorithms

    ERIC Educational Resources Information Center

    Fernandez, Ricardo Lopez; Garcia, Ana B. Sanchez

    2008-01-01

    The study of errors made in subtraction is a research subject approached from different theoretical premises that affect different components of the algorithmic process as triggers of their generation. In the following research an attempt has been made to investigate the typology and nature of errors which occur in subtractions and their evolution…

  20. Developing a Model to Support Students in Solving Subtraction

    ERIC Educational Resources Information Center

    Murdiyani, Nila Mareta; Zulkardi; Putri, Ratu Ilma Indra; van Eerde, Dolly; van Galen, Frans

    2013-01-01

    Subtraction has two meanings and each meaning leads to the different strategies. The meaning of "taking away something" suggests a direct subtraction, while the meaning of "determining the difference between two numbers" is more likely to be modeled as indirect addition. Many prior researches found that the second meaning and…

  1. Gain of a single gas electron multiplier

    NASA Astrophysics Data System (ADS)

    Nemallapudi, Mythra Varun

    Gas Electron Multiplier (GEM) is a gaseous detector used in particle detection and is known for its high rate capability. Ever since its invention in 1997, GEM was applied in many areas and recently has been proposed to be installed in the CMS high η regions for upgrade at LHC, CERN. A complete understanding of the working and gain behaviour does not exist. GEM gain is influenced by charging up and this has been variedly interpreted in literature lacking consensus. I have attempted in this work through simulations and measurements to achieve a better understanding of single GEM gain and how it is affected by various factors. Specific experimental methods which evolved with subsequent measurements were employed to systematically study the charging up effect. Information from simulations was applied to characterize measurements thereby enabling the development of a model for charging up. Conductivity mechanism of the dielectric used in GEM was analyzed and the resistivity measured. Gain free of charging up effects was measured and this is appropriate for comparison with simulations.

  2. Synthesis and characterization of multiply-tyrosinated, multiply-iodinated somatostatin analogs

    SciTech Connect

    Woltering, E A.; O'Dorisio, M S.; Murphy, W A.; Chen, F; Drouant, G J.; Espenan, G D.; Fisher, Darrell R.; Sharma, C; Diaco, D S.; Maloney, T M.; Fuselier, J A.; Nelson, J A.; O'Dorisio, T M.; Coy, D H.

    1999-02-01

    Radio-labeled somatostatin analogs have recently gained popularity as agents useful in intraoperative tumor localization, external scintigraphy and in situ radiotherapy. We have synthesized and characterized a series of novel N-terminally extended multiply-tyrosinated somatostatin analogs that possess high binding affinity for somatostatin receptors, exhibit biological activity comparable to the native peptide and retain these characteristics after iodination. These analogs can be radio-iodinated to high specific activities. Following radio-iodination, these analogs exhibit minimal radiolysis and may be clinically useful for tumor localization, scanning and therapy.

  3. User's manual for Axisymmetric Diffuser Duct (ADD) code. Volume 1: General ADD code description

    NASA Technical Reports Server (NTRS)

    Anderson, O. L.; Hankins, G. B., Jr.; Edwards, D. E.

    1982-01-01

    This User's Manual contains a complete description of the computer codes known as the AXISYMMETRIC DIFFUSER DUCT code or ADD code. It includes a list of references which describe the formulation of the ADD code and comparisons of calculation with experimental flows. The input/output and general use of the code is described in the first volume. The second volume contains a detailed description of the code including the global structure of the code, list of FORTRAN variables, and descriptions of the subroutines. The third volume contains a detailed description of the CODUCT code which generates coordinate systems for arbitrary axisymmetric ducts.

  4. User's manual for Axisymmetric Diffuser Duct (ADD) code. Volume 3: ADD code coordinate generator

    NASA Technical Reports Server (NTRS)

    Anderson, O. L.; Hankins, G. B., Jr.; Edwards, D. E.

    1982-01-01

    This User's Manual contains a complete description of the computer codes known as the Axisymmetric Diffuser Duct (ADD) code. It includes a list of references which describe the formulation of the ADD code and comparisons of calculation with experimental flows. The input/output and general use of the code is described in the first volume. The second volume contains a detailed description of the code including the global structure of the code, list of FORTRAN variables, and descriptions of the subroutines. The third volume contains a detailed description of the CODUCT code which generates coordinate systems for arbitrary axisymmetric ducts.

  5. Planar Monolithic Schottky Varactor Diode Millimeter-Wave Frequency Multipliers

    DTIC Science & Technology

    1992-06-01

    power 175 of the 80/160 GHz doubler. 6.23 The output power versus frequency for three 176 80/160 GHz chips. 6.24 The multiplier efficiency for...versions of the 31/94 GHz tripler. (iteration one). 8.33 Multiplier efficiency versus available 249 input power for the four versions of the 31/94 GHz ...8.48 Output power versus available input power 267 for the four versions of the 31/94 GHz tripler. (interation two). 22 8.49 Multiplier

  6. Using Joint Interviews to Add Analytic Value.

    PubMed

    Polak, Louisa; Green, Judith

    2016-10-01

    Joint interviewing has been frequently used in health research, and is the subject of a growing methodological literature. We review this literature, and build on it by drawing on a case study of how people make decisions about taking statins. This highlights two ways in which a dyadic approach to joint interviewing can add analytic value compared with individual interviewing. First, the analysis of interaction within joint interviews can help to explicate tacit knowledge and to illuminate the range of often hard-to-access resources that are drawn upon in making decisions. Second, joint interviews mitigate some of the weaknesses of interviewing as a method for studying practices; we offer a cautious defense of the often-tacit assumption that the "naturalness" of joint interviews strengthens their credibility as the basis for analytic inferences. We suggest that joint interviews are a particularly appropriate method for studying complex shared practices such as making health decisions.

  7. Independents add gas reserves, forego romance

    SciTech Connect

    Gill, D.

    1981-08-01

    Incentive pricing for low-permeability reservoirs and tax advantages for drilling them are 2 big reasons why more independents may start making a special effort to add gas reserves to their inventories. If so, it will be a change from past practices, which saw independents build up big gas positions by circumstance rather than by intention. There are always major refiners ready and willing to buy whole crude oil reservoirs from small producers, but purchasers willing to take gas fields in a single investment are few and far between. Lower-than-normal return on equity during the first 20 years, plus the heavy front-end cost of a frac necessary to produce the tight gas might dissuade independents from drilling tight gas sands, but those liabilities are offset by the higher price tight gas gets and the peculiar tax advantages of exploring for it that make a nice fit with the small operator's way of doing business.

  8. Technical innovation: Multidimensional computerized software enabled subtraction computed tomographic angiography.

    PubMed

    Bhatia, Mona; Rosset, Antoine; Platon, Alexandra; Didier, Dominique; Becker, Christoph D; Poletti, Pierre-Alexandre

    2010-01-01

    Computed tomographic angiography (CTA) is a frequent noninvasive alternative to digital subtraction angiography. We previously reported the development of a new subtraction software to overcome limitations of adjacent bone and calcification in CT angiographic subtraction. Our aim was to further develop and improve this fast and automated computerized software, universally available for free use and compatible with most CT scanners, thus enabling better delineation of vascular structures, artifact reduction, and shorter reading times with potential clinical benefits. This computer-based free software will be available as an open source in the next release of OsiriX at the Web site http://www.osirix-viewer.com.

  9. Prokaryotic suppression subtractive hybridization PCR cDNA subtraction, a targeted method to identify differentially expressed genes.

    PubMed

    De Long, Susan K; Kinney, Kerry A; Kirisits, Mary Jo

    2008-01-01

    Molecular biology tools can be used to monitor and optimize biological treatment systems, but the application of nucleic acid-based tools has been hindered by the lack of available sequences for environmentally relevant biodegradation genes. The objective of our work was to extend an existing molecular method for eukaryotes to prokaryotes, allowing us to rapidly identify differentially expressed genes for subsequent sequencing. Suppression subtractive hybridization (SSH) PCR cDNA subtraction is a technique that can be used to identify genes that are expressed under specific conditions (e.g., growth on a given pollutant). While excellent methods for eukaryotic SSH PCR cDNA subtraction are available, to our knowledge, no methods previously existed for prokaryotes. This work describes our methodology for prokaryotic SSH PCR cDNA subtraction, which we validated using a model system: Pseudomonas putida mt-2 degrading toluene. cDNA from P. putida mt-2 grown on toluene (model pollutant) or acetate (control substrate) was subjected to our prokaryotic SSH PCR cDNA subtraction protocol to generate subtraction clone libraries. Over 90% of the sequenced clones contained gene fragments encoding toluene-related enzymes, and 20 distinct toluene-related genes from three key operons were sequenced. Based on these results, prokaryotic SSH PCR cDNA subtraction shows promise as a targeted method for gene identification.

  10. Children with Attention Deficit Disorders. ADD Fact Sheet.

    ERIC Educational Resources Information Center

    Parker, Harvey C.

    This fact sheet summarizes basic information on Attention Deficit Disorders (ADD), including prevalence and characteristics, causes, identification, treatment, outcomes, and suggestions. Children with ADD comprise approximately 3-5 percent of the school age population, with boys significantly outnumbering girls. Of 14 characteristics of ADD, the…

  11. Sociophysics of sexism: normal and anomalous petrie multipliers

    NASA Astrophysics Data System (ADS)

    Eliazar, Iddo

    2015-07-01

    A recent mathematical model by Karen Petrie explains how sexism towards women can arise in organizations where male and female are equally sexist. Indeed, the Petrie model predicts that such sexism will emerge whenever there is a male majority, and quantifies this majority bias by the ‘Petrie multiplier’: the square of the male/female ratio. In this paper—emulating the shift from ‘normal’ to ‘anomalous’ diffusion—we generalize the Petrie model to a stochastic Poisson model that accommodates heterogeneously sexist men and woman, and that extends the ‘normal’ quadratic Petrie multiplier to ‘anomalous’ non-quadratic multipliers. The Petrie multipliers span a full spectrum of behaviors which we classify into four universal types. A variation of the stochastic Poisson model and its Petrie multipliers is further applied to the context of cyber warfare.

  12. Multiplier less high-speed squaring circuit for binary numbers

    NASA Astrophysics Data System (ADS)

    Sethi, Kabiraj; Panda, Rutuparna

    2015-03-01

    The squaring operation is important in many applications in signal processing, cryptography etc. In general, squaring circuits reported in the literature use fast multipliers. A novel idea of a squaring circuit without using multipliers is proposed in this paper. Ancient Indian method used for squaring decimal numbers is extended here for binary numbers. The key to our success is that no multiplier is used. Instead, one squaring circuit is used. The hardware architecture of the proposed squaring circuit is presented. The design is coded in VHDL and synthesised and simulated in Xilinx ISE Design Suite 10.1 (Xilinx Inc., San Jose, CA, USA). It is implemented in Xilinx Vertex 4vls15sf363-12 device (Xilinx Inc.). The results in terms of time delay and area is compared with both modified Booth's algorithm and squaring circuit using Vedic multipliers. Our proposed squaring circuit seems to have better performance in terms of both speed and area.

  13. Operational Safety Requirements Neutron Multiplier Facility in 329 Building

    SciTech Connect

    EA. Lepel

    1992-10-01

    The operational safety requirements (OSRs) presented in this report define the conditions, safe boundaries and management control needed for safely operating the Neutron Multiplier Facility in the 329 Building Annex.

  14. Auditory Reinforcement in Profoundly Retarded Multiply Handicapped Children

    ERIC Educational Resources Information Center

    Remington, R. E.; And Others

    1977-01-01

    Four profoundly retarded multiply handicapped children (with a mean age of 12 years) were placed in a situation where auditory stimulation was made contingent on a visually directed lever-pulling response. (Author/MH)

  15. Radial Fourier multipliers of Lp(R2)

    PubMed Central

    Carbery, Anthony; Gasper, George; Trebels, Walter

    1984-01-01

    We give sufficient conditions (in terms of differentiability and growth properties) for a radial function to be an Lp(R2) Fourier multiplier. These conditions are in the nature of best possible. PMID:16593468

  16. Morbidity of Early Spine Surgery in the Multiply Injured Patient

    DTIC Science & Technology

    2014-07-31

    Rivera JD, Gre- nier ES, Lehman RA, et al. (2012) Spinal column injuries among Americans in the global war on terrorism. J Bone Joint Surg Am 94:e135...surgery for multiply injured patients with operative spinal injuries remains unknown. The purported benefits of early intervention must be weighed...morbidity of early surgery on military casualties. The objective is to compare surgical morbidity of early spinal surgery in multiply injured patients

  17. Soft-collinear factorization and zero-bin subtractions

    SciTech Connect

    Chiu Juiyu; Fuhrer, Andreas; Kelley, Randall; Manohar, Aneesh V.; Hoang, Andre H.

    2009-03-01

    We study the Sudakov form factor for a spontaneously broken gauge theory using a (new) {delta}-regulator. To be well defined, the effective theory requires zero-bin subtractions for the collinear sectors. The zero-bin subtractions depend on the gauge boson mass M and are not scaleless. They have both finite and 1/{epsilon} contributions and are needed to give the correct anomalous dimension and low-scale matching contributions. We also demonstrate the necessity of zero-bin subtractions for soft-collinear factorization. We find that after zero-bin subtractions the form factor is the sum of the collinear contributions minus a soft mass-mode contribution, in agreement with a previous result of Idilbi and Mehen in QCD. This appears to conflict with the method-of-regions approach, where one gets the sum of contributions from different regions.

  18. Improvements in floating point addition/subtraction operations

    DOEpatents

    Farmwald, P.M.

    1984-02-24

    Apparatus is described for decreasing the latency time associated with floating point addition and subtraction in a computer, using a novel bifurcated, pre-normalization/post-normalization approach that distinguishes between differences of floating point exponents.

  19. High speed multiplier using Nikhilam Sutra algorithm of Vedic mathematics

    NASA Astrophysics Data System (ADS)

    Pradhan, Manoranjan; Panda, Rutuparna

    2014-03-01

    This article presents the design of a new high-speed multiplier architecture using Nikhilam Sutra of Vedic mathematics. The proposed multiplier architecture finds out the compliment of the large operand from its nearest base to perform the multiplication. The multiplication of two large operands is reduced to the multiplication of their compliments and addition. It is more efficient when the magnitudes of both operands are more than half of their maximum values. The carry save adder in the multiplier architecture increases the speed of addition of partial products. The multiplier circuit is synthesised and simulated using Xilinx ISE 10.1 software and implemented on Spartan 2 FPGA device XC2S30-5pq208. The output parameters such as propagation delay and device utilisation are calculated from synthesis results. The performance evaluation results in terms of speed and device utilisation are compared with earlier multiplier architecture. The proposed design has speed improvements compared to multiplier architecture presented in the literature.

  20. Advanced Background Subtraction Applied to Aeroacoustic Wind Tunnel Testing

    NASA Technical Reports Server (NTRS)

    Bahr, Christopher J.; Horne, William C.

    2015-01-01

    An advanced form of background subtraction is presented and applied to aeroacoustic wind tunnel data. A variant of this method has seen use in other fields such as climatology and medical imaging. The technique, based on an eigenvalue decomposition of the background noise cross-spectral matrix, is robust against situations where isolated background auto-spectral levels are measured to be higher than levels of combined source and background signals. It also provides an alternate estimate of the cross-spectrum, which previously might have poor definition for low signal-to-noise ratio measurements. Simulated results indicate similar performance to conventional background subtraction when the subtracted spectra are weaker than the true contaminating background levels. Superior performance is observed when the subtracted spectra are stronger than the true contaminating background levels. Experimental results show limited success in recovering signal behavior for data where conventional background subtraction fails. They also demonstrate the new subtraction technique's ability to maintain a proper coherence relationship in the modified cross-spectral matrix. Beam-forming and de-convolution results indicate the method can successfully separate sources. Results also show a reduced need for the use of diagonal removal in phased array processing, at least for the limited data sets considered.

  1. Comparison of iodine K-edge subtraction and fluorescence subtraction imaging in an animal system

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Zhu, Y.; Bewer, B.; Zhang, L.; Korbas, M.; Pickering, I. J.; George, G. N.; Gupta, M.; Chapman, D.

    2008-09-01

    K-Edge Subtraction (KES) utilizes the discontinuity in the X-ray absorption across the absorption edge of the selected contrast element and creates an image of the projected density of the contrast element from two images acquired just above and below the K-edge of the contrast element. KES has proved to be powerful in coronary angiography, micro-angiography, bronchography, and lymphatic imaging. X-ray fluorescence imaging is a successful technique for the detection of dilute quantities of elements in specimens. However, its application at high X-ray energies (e.g. at the iodine K-edge) is complicated by significant Compton background, which may enter the energy window set for the contrast material's fluorescent X-rays. Inspired by KES, Fluorescence Subtraction Imaging (FSI) is a technique for high-energy (>20 keV) fluorescence imaging using two different incident beam energies just above and below the absorption edge of a contrast element (e.g. iodine). The below-edge image can be assumed as a "background" image, which includes Compton scatter and fluorescence from other elements. The above-edge image will contain nearly identical spectral content as the below-edge image but will contain the additional fluorescence of the contrast element. This imaging method is especially promising with thick objects with dilute contrast materials, significant Compton background, and/or competing fluorescence lines from other materials. A quality factor is developed to facilitate the comparison. The theoretical value of the quality factor sets the upper limit that an imaging method can achieve when the noise is Poisson limited. The measured value of this factor makes two or more imaging methods comparable. Using the Hard X-ray Micro-Analysis (HXMA) beamline at the Canadian Light Source (CLS), the techniques of FSI and KES were critically compared, with reference to radiation dose, image acquisition time, resolution, signal-to-noise ratios, and quality factor.

  2. Four-quadrant analogue multiplier using operational amplifier

    NASA Astrophysics Data System (ADS)

    Riewruja, Vanchai; Rerkratn, Apinai

    2011-04-01

    A method to realise a four-quadrant analogue multiplier using general-purpose operational amplifiers (opamps) as only the active elements is described in this article. The realisation method is based on the quarter-square technique, which utilises the inherent square-law characteristic of class AB output stage of the opamp. The multiplier can be achieved from the proposed structure with using either bipolar or complementary metal-oxide-semiconductor (CMOS) opamps. The operation principle of the proposed multiplier has been confirmed by PSPICE analogue simulation program. Simulation results reveal that the principle of proposed scheme provides an adequate performance for a four-quadrant analogue multiplier. Experimental implementations of the proposed multiplier using bipolar and CMOS opamps are performed to verify the circuit performances. Measured results of the experimental proposed schemes based on the use of bipolar and CMOS opamps with supply voltage ±2.4 V show the worst-case relative errors of 0.32% and 0.47%, and the total harmonic distortions of 0.47% and 0.98%, respectively.

  3. Representation of the inverse of a frame multiplier.

    PubMed

    Balazs, P; Stoeva, D T

    2015-02-15

    Certain mathematical objects appear in a lot of scientific disciplines, like physics, signal processing and, naturally, mathematics. In a general setting they can be described as frame multipliers, consisting of analysis, multiplication by a fixed sequence (called the symbol), and synthesis. In this paper we show a surprising result about the inverse of such operators, if any, as well as new results about a core concept of frame theory, dual frames. We show that for semi-normalized symbols, the inverse of any invertible frame multiplier can always be represented as a frame multiplier with the reciprocal symbol and dual frames of the given ones. Furthermore, one of those dual frames is uniquely determined and the other one can be arbitrarily chosen. We investigate sufficient conditions for the special case, when both dual frames can be chosen to be the canonical duals. In connection to the above, we show that the set of dual frames determines a frame uniquely. Furthermore, for a given frame, the union of all coefficients of its dual frames is dense in [Formula: see text]. We also introduce a class of frames (called pseudo-coherent frames), which includes Gabor frames and coherent frames, and investigate invertible pseudo-coherent frame multipliers, allowing a classification for frame-type operators for these frames. Finally, we give a numerical example for the invertibility of multipliers in the Gabor case.

  4. Blind Source Separation Algorithms for PSF Subtraction from Direct Imaging

    NASA Astrophysics Data System (ADS)

    Shapiro, Jacob; Ranganathan, Nikhil; Savransky, Dmitry; Ruffio, Jean-Baptise; Macintosh, Bruce; GPIES Team

    2017-01-01

    The principal difficulty with detecting planets via direct imaging is that the target signal is similar in magnitude, or fainter, than the noise sources in the image. To compensate for this, several methods exist to subtract the PSF of the host star and other confounding noise sources. One of the most effective methods is Karhunen-Loève Image Processing (KLIP). The core algorithm within KLIP is Principal Component Analysis, which is a member of a class of algorithms called Blind Source Separation (BSS).We examine three other BSS algorithms that may potentially also be used for PSF subtraction: Independent Component Analysis, Stationary Subspace Analysis, and Common Spatial Pattern Filtering. The underlying principles of each of the algorithms is discussed, as well as the processing steps needed to achieve PSF subtraction. The algorithms are examined both as primary PSF subtraction techniques, as well as additional postprocessing steps used with KLIP.These algorithms have been used on data from the Gemini Planet Imager, analyzing images of β Pic b. To build a reference library, both Angular Differential Imaging and Spectral Differential Imaging were used. To compare to KLIP, three major metrics are examined: computation time, signal-to-noise ratio, and astrometric and photometric biases in different image regimes (e.g., speckle-dominated compared to Poisson-noise dominated). Preliminary results indicate that these BSS algorithms improve performance when used as an enhancement for KLIP, and that they can achieve similar SNR when used as the primary method of PSF subtraction.

  5. Inverse Jacobi multipliers and first integrals for nonautonomous differential systems

    NASA Astrophysics Data System (ADS)

    Buică, Adriana; García, Isaac A.

    2015-06-01

    In this paper, we consider nonautonomous differential systems of arbitrary dimension and first find expressions for their inverse Jacobi multipliers and first integrals in some nonautonomous invariant set in terms of the solutions of the differential system. Given an inverse Jacobi multiplier V, we find a relation between the Poincaré translation map Π at time T that extends to arbitrary dimensions the fundamental relation for scalar equations, , found in García et al. (Trans Am Math Soc 362:3591-3612, 2010). The main result guarantees the existence of continua of T-periodic solutions for T-periodic systems in the presence of T-periodic first integrals and inverse Jacobi multipliers.

  6. MULTIPLY: Development of a European HSRL Airborne Facility

    NASA Astrophysics Data System (ADS)

    Binietoglou, Ioannis; Serikov, Ilya; Nicolae, Doina; Amiridis, Vassillis; Belegante, Livio; Boscornea, Andrea; Brugmann, Bjorn; Costa Suros, Montserrat; Hellmann, David; Kokkalis, Panagiotis; Linne, Holger; Stachlewska, Iwona; Vajaiac, Sorin-Nicolae

    2016-08-01

    MULTIPLY is a novel airborne high spectral resolution lidar (HSRL) currently under development by a consortium of European institutions from Romania, Germany, Greece, and Poland. Its aim is to contribute to calibration and validations activities of the upcoming ESA aerosol sensing missions like ADM-Aeolus, EarthCARE and the Sentinel-3/-4/-5/-5p which include products related to atmospheric aerosols. The effectiveness of these missions depends on independent airborne measurements to develop and test the retrieval methods, and validate mission products following launch. The aim of ESA's MULTIPLY project is to design, develop, and test a multi-wavelength depolarization HSRL for airborne applications. The MULTIPLY lidar will deliver the aerosol extinction and backscatter coefficient profiles at three wavelengths (355nm, 532nm, 1064nm), as well as profiles of aerosol intensive parameters (Ångström exponents, extinction- to-backscatter ratios, and linear particle depolarization ratios).

  7. Multiply-Twisted Helices of Various Inter-Round Couplings

    NASA Astrophysics Data System (ADS)

    Ugajin, R.; Watanabe, Y.; Mori, Y.

    Multiply-twisted helices in which a helical chain of components, i.e. atoms or nanoclusters, is twisted, producing a doubly-twisted helix, which if itself is twisted produces a triply-twisted helix, and so on, are characterized by inter-round couplings, through which electrons in the structure transit between adjacent rounds. The multiply-twisted helix of inter-round couplings via a chain of sites and that of inter-round couplings through a single site are compared with that of the direct inter-round couplings previously reported by R. Ugajin [J. Nanosci. Nanotechnol. 1, 227 (2001)]. Monte Carlo simulations of classical spins suggest that the multiply-twisted helix of inter-round couplings through a single site, in which the Curie temperature of ferromagnetic transition is robust against the change of a basal helix, might be critical among these three types.

  8. Multiplier Accounting of Indian Mining Industry: The Application

    NASA Astrophysics Data System (ADS)

    Hussain, Azhar; Karmakar, Netai Chandra

    2016-10-01

    In the previous paper (Hussain and Karmakar in Inst Eng India Ser, 2014. doi: 10.1007/s40033-014-0058-0), the concepts of input-output transaction matrix and multiplier were explained in detail. Input-output multipliers are indicators used for predicting the total impact on an economy due to changes in its industrial demand and output which is calculated using transaction matrix. The aim of this paper is to present an application of the concepts with respect to the mining industry, showing progress in different sectors of mining with time and explaining different outcomes from the results obtained. The analysis shows that a few mineral industries saw a significant growth in their multiplier values over the years.

  9. Spatial frequency multiplier with active linearly tapered slot antenna array

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.; Lee, Richard Q.

    1994-01-01

    A frequency multiplier with active linearly tapered slot antennas (LTSA's) has been demonstrated at the second harmonic frequency. In each antenna element, a GaAs monolithic microwave integrated circuit (MMIC) distributed amplifier is integrated with two LTSA's. The multiplier has a very wide bandwidth and large dynamic range. The fundamental-to-second harmonic conversion efficiency is 8.1 percent. The spatially combined second harmonic signal is 50 dB above the noise level. The design is suitable for constructing a large array using monolithic integration techniques.

  10. Californium Multiplier Part I: design for neutron radiography

    SciTech Connect

    Crosbie, K.L.; Preskitt, C.A.; John, J.; Hastings, J.D.

    1982-01-01

    The Californium Multiplier (CFX) is a subcritical assembly of enriched uranium surrounding a californium-252 neutron source. The function of the CFX is to multiply the neutrons emitted by the source to a number sufficient for neutron radiography. The CFX is designed to provide a collimated beam of thermal neutrons from which the gamma radiation is filtered, and the scattered neutrons are reduced to make it suitable for high resolution radiography. The entire system has inherent safety features, which provide for system and personnel safety, and it operates at moderate cost. In Part I, the CFX and the theory of its operation are described in detail.

  11. Proposed smart integrated-optical preprocessor using holographic subtraction

    NASA Technical Reports Server (NTRS)

    Verber, C. M.; Vahey, D. W.

    1979-01-01

    The paper presents a proposed integrated-optical preprocessor with a holographic subtraction. It is based on an optical analog of a set of N analog voltages formed by passing an optical plane wave, confined in an electrooptic waveguide, under a set of N electrodes to which the voltages are applied; in the limit in which diffraction is ignored, the wavefront of the emerging guided wave will have superimposed upon it N discrete phase shifts. Processors which operate upon voltages encoded in this manner are being fabricated; they include a comparator in which incoming data are compared to a holographic record of the optical analog of a reference set, and a 'smart' system based upon holographic self-subtraction, in which the processor can independently adapt to changes in background information. The preprocessor operation is described in the screening, identification, and the self-subtraction modes, and implementation of devices in an integrated optical configuration is discussed.

  12. Sky background subtraction with fiber-fed spectrographs

    NASA Astrophysics Data System (ADS)

    Puech, M.; Rodrigues, M.; Yang, Y.; Flores, H.; Royer, F.; Disseau, K.; Gonçalves, T.; Hammer, F.; Cirasuolo, M.; Evans, C. J.; Li Causi, G.; Maiolino, R.; Melo, C.

    2014-08-01

    Fiber-fed spectrographs can now have throughputs equivalent to slit spectrographs. However, the sky subtraction accuracy that can be reached on such instruments has often been pinpointed as one of their major issues, in relation to difficulties in scattered light and flat-field corrections or throughput losses associated with fibers. Using technical time observations with FLAMES-GIRAFFE, two observing techniques, namely dual staring and cross beam switching modes, were tested and the resulting sky subtraction accuracy reached in both cases was quantified. Results indicate that an accuracy of 0.6% on the sky subtraction can be reached, provided that the cross beam switching mode is used. This is very encouraging regarding the detection of very faint sources with future fiber-fed spectrographs such as VLT/MOONS or E-ELT/MOSAIC.

  13. pyKLIP: PSF Subtraction for Exoplanets and Disks

    NASA Astrophysics Data System (ADS)

    Wang, Jason J.; Ruffio, Jean-Baptise; De Rosa, Robert J.; Aguilar, Jonathan; Wolff, Schuyler G.; Pueyo, Laurent

    2015-06-01

    pyKLIP subtracts out the stellar PSF to search for directly-imaged exoplanets and disks using a Python implementation of the Karhunen-Loève Image Projection (KLIP) algorithm. pyKLIP supports ADI, SDI, and ADI+SDI to model the stellar PSF and offers a large array of PSF subtraction parameters to optimize the reduction. pyKLIP relies on a minimal amount of dependencies (numpy, scipy, and astropy) and parallelizes the KLIP algorithm to speed up the reduction. pyKLIP supports GPI and P1640 data and can interface with other data sources with the addition of new modules. It also can inject simulated planets and disks as well as automatically search for point sources in PSF-subtracted data.

  14. Digital Subtraction Fluoroscopic System With Tandem Video Processing Units

    NASA Astrophysics Data System (ADS)

    Gould, Robert G.; Lipton, Martin J.; Mengers, Paul; Dahlberg, Roger

    1981-07-01

    A real-time digital fluoroscopic system utilizing two video processing units (Quantex) in tandem to produce continuous subtraction images of peripheral and internal vessels following intravenous contrast media injection has been inves-tigated. The first processor subtracts a mask image consisting of an exponentially weighted moving average of N1 frames (N1 = 2k where k = 0.7) from each incoming video frame, divides by N1, and outputs the resulting difference image to the second processor. The second unit continuously averages N2 incoming frames (N2 = 2k) and outputs to a video monitor and analog disc recorder. The contrast of the subtracted images can be manipulated by changing gain or by a non-linear output transform. After initial equipment adjustments, a subtraction sequence can be produced without operator interaction with the processors. Alternatively, the operator can freeze the mask and/or the subtracted output image at any time during the sequence. Raw data is preserved on a wide band video tape recorder permitting retrospective viewing of an injection sequence with different processor settings. The advantage of the tandem arrangement is that it has great flexibility in varying the duration and the time of both the mask and injection images thereby minimizing problems of registration between them. In addition, image noise is reduced by compiling video frames rather than by using a large radiation dose for a single frame, which requires a wide dynamic range video camera riot commonly available in diagnostic x-ray equipment. High quality subtraction images of arteries have been obtained in 15 anesthetized dogs using relatively low exposure rates (10-12 μR/video frame) modest volumes of contrast medium (0.5-1 ml/kg), and low injection flow rates (6-10 ml/sec). The results/ achieved so far suggest that this system has direct clinical applications.

  15. Digital subtraction angiography: principles and pitfalls of image improvement techniques.

    PubMed

    Levin, D C; Schapiro, R M; Boxt, L M; Dunham, L; Harrington, D P; Ergun, D L

    1984-09-01

    The technology of imaging methods in digital subtraction angiography (DSA) is discussed in detail. Areas covered include function of the video camera in both interlaced and sequential scan modes, digitization by the analog-to-digital converter, logarithmic signal processing, dose rates, and acquisition of images using frame integration and pulsed-sequential techniques. Also discussed are various methods of improving image content and quality by both hardware and software modifications. These include the development of larger image intensifiers, larger matrices, video camera improvements, reregistration, hybrid subtraction, matched filtering, recursive filtering, DSA tomography, and edge enhancement.

  16. Social Capital: Does It Add to the Health Inequalities Debate?

    ERIC Educational Resources Information Center

    Chappell, Neena L.; Funk, Laura M.

    2010-01-01

    This paper empirically examines the relationship between advantage, social capital and health status to assess (a) whether social capital adds explanatory power to what we already know about the relationship between advantage and health and (b) whether social capital adds anything beyond its component parts, namely social participation and trust.…

  17. Discovering Focus: Helping Students with ADD (Attention Deficit Disorder)

    ERIC Educational Resources Information Center

    Valkenburg, Jim

    2012-01-01

    Attention Deficit Disorder (ADD) is a neurological disorder which effects learning and that has a confusing set of diagnostic symptoms and an even more confusing set of remedies ranging from medication to meditation to nothing at all. Current neurological research suggests, however, that there are strategies that the individual with ADD can use to…

  18. Dyslexia and ADD: 20 Questions Parents Ask. Children with Disabilities.

    ERIC Educational Resources Information Center

    Pickering, Joyce S.

    2002-01-01

    This article uses a question-answer format to present information for parents on dyslexia and attention deficit disorders (ADD). Information includes typical behaviors and skills of children with dyslexia or ADD, how parents can help their children, and the use of medication to control hyperactivity. (KB)

  19. Capability and Schur multiplier of a pair of Lie algebras

    NASA Astrophysics Data System (ADS)

    Johari, Farangis; Parvizi, Mohsen; Niroomand, Peyman

    2017-04-01

    The aim of this work is to find some criteria for detecting the capability of a pair of Lie algebras. We characterize the exact structure of all pairs of capable Lie algebras in the class of abelian and Heisenberg ones. Among the other results, we also give some exact sequences on the Schur multiplier and exterior product of Lie algebras.

  20. Fixed-Tuned Submillimeter Waveguide Multipliers Using MMIC Technology

    NASA Technical Reports Server (NTRS)

    Bruston, J.; Kim, M.; Martin, S. C.; Pease, A.; Smith, R. P.; Siegel, P. H.

    1997-01-01

    In preparation for the insturment ammouncement of opportunity for the Far Infrared and Submillimeter Space Telescope, and ESA/NASA space astrophysics observatory mission, local oscillator sources at high frequencies (1200 GHz) are being developed. As part of a multiplier chain beginning at 100 GHz we are developing single and multiple diode waveguide circuits up to 640 GHz.

  1. Gilles de la Tourette Disease in Multiply Disabled Children.

    ERIC Educational Resources Information Center

    Kerbeshian, Jacob; And Others

    1985-01-01

    Giles de La Tourette disease (TD) is characterized by multiform changing vocal and motor tics with a wide range of accompanying behavioral symptoms. The range of tics and behavioral problems seen in TD is described along with a typcial case report in a multiply disabled child. Diagnostic criteria, and treatment recommendations are also given.…

  2. Familiar Sports and Activities Adapted for Multiply Impaired Persons.

    ERIC Educational Resources Information Center

    Schilling, Mary Lou, Ed.

    1984-01-01

    Means of adapting some familiar and popular physical activities for multiply impaired persons are described. Games reviewed are dice baseball, one base baseball, in-house bowling, wheelchair bowling, ramp bowling, swing-ball bowling, table tennis, shuffleboard, beanbag bingo and tic-tac-toe, balloon basketball, circle football, and wheelchair…

  3. Multiplying Is More than Math--It's Also Good Management

    ERIC Educational Resources Information Center

    Foster, Elise; Wiseman, Liz

    2015-01-01

    Studying more than 400 educational leaders, the authors propose a new model for leadership and management rooted in the belief that there is latent intelligence inside schools and educational organizations. Their findings suggest two dramatically different types of leaders, Multipliers and Diminishers. The five disciplines that distinguish…

  4. Multiply-Impaired Blind Children: A National Problem.

    ERIC Educational Resources Information Center

    Graham, Milton D.

    In 1966, a national survey reported on 8,887 multiply impaired (MI) blind children. About 56% were boys; 85% had been blind since before age 3, and half were totally blind. The principal causes of blindness were retrolental fibroplasia and congenital cataracts. Almost 63% had two or more additional disabilities (86.8% of those under age 6), such…

  5. The structure of Airy's stress function in multiply connected regions

    NASA Technical Reports Server (NTRS)

    Grioli, Giusippe

    1951-01-01

    In solving two-dimensional problems using Airy's stress function for multiply connected regions, the form of the function depends on the dislocations and boundary forces present. The structure of Airy's function is shown to consist of a part expressible in terms of boundary forces and a part expressible in the manner of Poincare. Meanings of the constants occurring in Poincare's expression are discussed.

  6. Medium power voltage multipliers with a large number of stages

    NASA Technical Reports Server (NTRS)

    Harrigill, W. T.; Myers, I. T.

    1978-01-01

    Voltage multiplier techniques are extended at medium power levels to larger multiplication ratios. A series of dc-dc converters were built, with from 20 to 45 stages and with power levels up to 100 watts. Maximum output voltages were about 10,000 volts.

  7. Multiply-Constrained Semantic Search in the Remote Associates Test

    ERIC Educational Resources Information Center

    Smith, Kevin A.; Huber, David E.; Vul, Edward

    2013-01-01

    Many important problems require consideration of multiple constraints, such as choosing a job based on salary, location, and responsibilities. We used the Remote Associates Test to study how people solve such multiply-constrained problems by asking participants to make guesses as they came to mind. We evaluated how people generated these guesses…

  8. Problems with Accurate Atomic Lfetime Measurements of Multiply Charged Ions

    SciTech Connect

    Trabert, E

    2009-02-19

    A number of recent atomic lifetime measurements on multiply charged ions have reported uncertainties lower than 1%. Such a level of accuracy challenges theory, which is a good thing. However, a few lessons learned from earlier precision lifetime measurements on atoms and singly charged ions suggest to remain cautious about the systematic errors of experimental techniques.

  9. Treatment of multiply controlled destructive behavior with food reinforcement.

    PubMed

    Adelinis, J D; Piazza, C C; Goh, H L

    2001-01-01

    We evaluated the extent to which the positive reinforcement of communication would reduce multiply controlled destructive behavior in the absence of relevant extinction components. When edible reinforcement for appropriate communication and nonfood reinforcers for problem behavior were available simultaneously, responding was allocated almost exclusively toward the behavior that produced edible reinforcement.

  10. Treatment of multiply controlled destructive behavior with food reinforcement.

    PubMed Central

    Adelinis, J D; Piazza, C C; Goh, H L

    2001-01-01

    We evaluated the extent to which the positive reinforcement of communication would reduce multiply controlled destructive behavior in the absence of relevant extinction components. When edible reinforcement for appropriate communication and nonfood reinforcers for problem behavior were available simultaneously, responding was allocated almost exclusively toward the behavior that produced edible reinforcement. PMID:11317997

  11. Hybrid Voltage-Multipliers Based Switching Power Converters

    NASA Astrophysics Data System (ADS)

    Rosas-Caro, Julio C.; Mayo-Maldonado, Jonathan C.; Vazquez-Bautista, Rene Fabian; Valderrabano-Gonzalez, Antonio; Salas-Cabrera, Ruben; Valdez-Resendiz, Jesus Elias

    2011-08-01

    This work presents a derivation of PWM DC-DC hybrid converters by combining traditional converters with the Cockcroft-Walton voltage multiplier, the voltage multiplier of each converter is driven with the same transistor of the basic topology; this fact makes the structure of the new converters very simple and provides high-voltage gain. The traditional topologies discussed are the boost, buck-boost, Cuk and SEPIC. They main features of the discussed family are: (i) high-voltage gain without using extreme duty cycles or transformers, which allow high switching frequency and (ii) low voltage stress in switching devices, along with modular structures, and more output levels can be added without modifying the main circuit, which is highly desirable in some applications such as renewable energy generation systems. It is shown how a multiplier converter can become a generalized topology and how some of the traditional converters and several state-of-the-art converters can be derived from the generalized topologies and vice-versa. All the discussed converters were simulated, additionally experimental results are provided with an interleaved multiplier converter.

  12. Isolation of ultrasonic scattering by wavefield baseline subtraction

    NASA Astrophysics Data System (ADS)

    Dawson, Alexander J.; Michaels, Jennifer E.; Michaels, Thomas E.

    2016-03-01

    Wavefield imaging generally refers to the measurement of signals over a two-dimensional rectilinear grid that originate from a spatially fixed source. Subtraction of such wavefields is investigated as a means of separating scattered signals from the total wavefield; that is, baseline wavefield data acquired from a defect-free specimen are subtracted from analogous data acquired after introduction of a defect. The wavefields considered here are generated by a 5 MHz angle-beam probe and measured over an area of the accessible specimen surface using a laser vibrometer. The primary challenge in isolating the scattered waves is imperfect temporal and spatial alignment of the two wavefields. Two methods for aligning the wavefields in space and time prior to performing baseline subtraction are presented and their efficacy is evaluated using data acquired before and after introducing notches that originate from a through-hole. Although perfect baseline subtraction is not achieved, the improvement in performance after alignment using either method allows for scattered waves from small defects to be separated and visualized, even when their amplitudes are much smaller than those of the incident waves.

  13. Teaching Addition and Subtraction Facts: A Chinese Perspective.

    ERIC Educational Resources Information Center

    Sun, Wei; Zhang, Joanne Y.

    2001-01-01

    Presents an issue that arises in every country: How can teachers best help children master basic addition and subtraction facts? Discusses how this is handled in China and highlights the impact that language has on how children think about numbers. (KHR)

  14. Teaching Children about the Inverse Relation between Addition and Subtraction

    ERIC Educational Resources Information Center

    Nunes, Terezinha; Bryant, Peter; Hallett, Darcy; Bell, Daniel; Evans, Deborah

    2009-01-01

    Two intervention studies are described. Both were designed to study the effects of teaching children about the inverse relation between addition and subtraction. The interventions were successful with 8-year-old children in Study 1 and to a limited extent with 5-year-old children in Study 2. In Study 1 teaching children about inversion increased…

  15. Children's Understanding of the Addition/Subtraction Complement Principle

    ERIC Educational Resources Information Center

    Torbeyns, Joke; Peters, Greet; De Smedt, Bert; Ghesquière, Pol; Verschaffel, Lieven

    2016-01-01

    Background: In the last decades, children's understanding of mathematical principles has become an important research topic. Different from the commutativity and inversion principles, only few studies have focused on children's understanding of the addition/subtraction complement principle (if a - b = c, then c + b = a), mainly relying on verbal…

  16. On the Standard Rounding Rule for Addition and Subtraction.

    ERIC Educational Resources Information Center

    Lee, Wei; Mulliss, Christopher L.; Chu, Hung-Chih

    2000-01-01

    Investigates the commonly suggested rounding rule for addition and subtraction including its derivation from a basic assumption. Uses Monte-Carlo simulations to show that this rule predicts the minimum number of significant digits needed to preserve precision 100% of the time. (Author/KHR)

  17. Addition and Subtraction by Students with Down Syndrome

    ERIC Educational Resources Information Center

    Herrera, Aurelia Noda; Bruno, Alicia; Gonzalez, Carina; Moreno, Lorenzo; Sanabria, Hilda

    2011-01-01

    We present a research report on addition and subtraction conducted with Down syndrome students between the ages of 12 and 31. We interviewed a group of students with Down syndrome who executed algorithms and solved problems using specific materials and paper and pencil. The results show that students with Down syndrome progress through the same…

  18. A New Sky Subtraction Technique for Low Surface Brightness Data

    NASA Astrophysics Data System (ADS)

    Katkov, I. Y.; Chilingarian, I. V.

    2011-07-01

    We present a new approach to the sky subtraction for long-slit spectra that is suitable for low-surface brightness objects based on the controlled reconstruction of the night sky spectrum in the Fourier space using twilight or arc-line frames as references. It can be easily adopted for FLAMINGOS-type multi-slit data. Compared to existing sky subtraction algorithms, our technique is taking into account variations of the spectral line spread along the slit thus qualitatively improving the sky subtraction quality for extended targets. As an example, we show how the stellar metallicity and stellar velocity dispersion profiles in the outer disc of the spiral galaxy NGC5440 are affected by the sky subtraction quality. Our technique is used in the survey of early-type galaxies carried out at the Russian 6-m telescope, and it strongly increases the scientific potential of large amounts of long-slit data for nearby galaxies available in major data archives.

  19. Enriching Addition and Subtraction Fact Mastery through Games

    ERIC Educational Resources Information Center

    Bay-Williams, Jennifer M.; Kling, Gina

    2014-01-01

    The learning of "basic facts"--single-digit combinations for addition, subtraction, multiplication, and division--has long been a focus of elementary school mathematics. Many people remember completing endless worksheets, timed tests, and flash card drills as they attempted to "master" their basic facts as children. However,…

  20. Children's Understanding of the Relationship between Addition and Subtraction

    ERIC Educational Resources Information Center

    Gilmore, Camilla K.; Spelke, Elizabeth S.

    2008-01-01

    In learning mathematics, children must master fundamental logical relationships, including the inverse relationship between addition and subtraction. At the start of elementary school, children lack generalized understanding of this relationship in the context of exact arithmetic problems: they fail to judge, for example, that 12 + 9 - 9 yields…

  1. The Use of Taught and Invented Methods of Subtraction.

    ERIC Educational Resources Information Center

    Perry, A. D.; Stacey, Kaye

    1994-01-01

    Attempted to establish the incidence of using taught algorithms versus invented methods of subtraction in (n=1,370) male secondary school students and to relate the use of invented methods to age, mathematical achievement, and lateral thinking ability. Use of invented algorithms increased with age. (23 references) (MKR)

  2. Adding and Subtracting Vectors: The Problem with the Arrow Representation

    ERIC Educational Resources Information Center

    Heckler, Andrew F.; Scaife, Thomas M.

    2015-01-01

    A small number of studies have investigated student understanding of vector addition and subtraction in generic or introductory physics contexts, but in almost all cases the questions posed were in the vector arrow representation. In a series of experiments involving over 1000 students and several semesters, we investigated student understanding…

  3. "Abuelita" Epistemologies: Counteracting Subtractive Schools in American Education

    ERIC Educational Resources Information Center

    Gonzales, Sandra M.

    2015-01-01

    This autoethnographic inquiry examines the intersection of elder epistemology and subtractive education, exploring how one "abuelita" countered her granddaughter's divestment of Mexican-ness. I demonstrate how the grandmother used "abuelita" epistemologies to navigate this tension and resist the assimilative pressures felt…

  4. 'Pokemon Go' Players Add 2,000 Steps a Day

    MedlinePlus

    ... Pokemon Go' Players Add 2,000 Steps a Day Smartphone game benefits overweight, sedentary people most, researchers ... as likely to walk 10,000 steps a day than they were before taking up the game, ...

  5. Top 5 Ways to Help Students with ADD/ADHD

    ERIC Educational Resources Information Center

    Johnson, Kathy

    2011-01-01

    This article suggests five ways to help students with ADD/ADHD. These are: (1) Integrate the primitive reflexes; (2) Diet; (3) Visual attention; (4) Help for auditory attention; and (5) Cognitive training.

  6. TDRS-K to Add to Vital Space Network

    NASA Video Gallery

    NASA officials discuss the launch of the TDRS-K spacecraft to add to the space network that enables communications between the International Space Station and Earth-orbiting satellites and ground c...

  7. Proton Transfer Reactivity of Large Multiply Charged Ions

    PubMed Central

    Williams, Evan R.

    2005-01-01

    Charge-charge interactions dramatically influence the dissociation and proton transfer reactivity of large multiply protonated ions. In combination with tandem mass spectrometry, proton transfer reactions have been used to determine the charge state of an ion and to increase the effective mass resolution of electrospray ionization mass spectra. A model for the proton transfer reactivity of multiply protonated ions, in which protons are assigned to specific sites in an ion based on the intrinsic reactivity of the site and the sum of point-charge Coulomb interactions between charges, is discussed. In combination with experimentally measured rates of proton transfer to bases of known gas-phase basicity, information about the intramolecular electrostatic interactions, gas-phase ion conformation and maximum charge state of an ion produced by electrospray ionization can be obtained. PMID:8799309

  8. Californium Multiplier. Part I. Design for neutron radiography

    SciTech Connect

    Crosbie, K.L.; Preskitt, C.A.; John, J.; Hastings, J.D.

    1982-04-01

    The Californium Multiplier (CFX) is a subcritical assembly of enriched uranium surrounding a californium-252 neutron source. The function of the CFX is to multiply the neutrons emitted by the source to a number sufficient for neutron radiography. The CFX is designed to provide a collimated beam of thermal neutrons from which the gamma radiation is filtered, and the scattered neutrons are reduced to make it suitable for high resolution radiography. The entire system has inherent safety features, which provide for system and personnel safety, and it operates at moderate cost. In Part I, the CFX and the theory of its operation are described in detail. Part II covers the performance of the Mound Facility CFX.

  9. Mass-dependent channel electron multiplier operation. [for ion detection

    NASA Technical Reports Server (NTRS)

    Fields, S. A.; Burch, J. L.; Oran, W. A.

    1977-01-01

    The absolute counting efficiency and pulse height distributions of a continuous-channel electron multiplier used in the detection of hydrogen, argon and xenon ions are assessed. The assessment technique, which involves the post-acceleration of 8-eV ion beams to energies from 100 to 4000 eV, provides information on counting efficiency versus post-acceleration voltage characteristics over a wide range of ion mass. The charge pulse height distributions for H2 (+), A (+) and Xe (+) were measured by operating the experimental apparatus in a marginally gain-saturated mode. It was found that gain saturation occurs at lower channel multiplier operating voltages for light ions such as H2 (+) than for the heavier ions A (+) and Xe (+), suggesting that the technique may be used to discriminate between these two classes of ions in electrostatic analyzers.

  10. Photoelectron Angular Distribution and Molecular Structure in Multiply Charged Anions

    SciTech Connect

    Xing, Xiaopeng; Wang, Xue B.; Wang, Lai S.

    2009-02-12

    Photoelectrons emitted from multiply charged anions (MCAs) carry information of the intramolecular Coulomb repulsion (ICR), which is dependent on molecular structures. Using photoelectron imaging, we observed the effects of ICR on photoelectron angular distributions (PAD) of the three isomers of benzene dicarboxylate dianions C6H4(CO2)22– (o-, m- and p-BDC2–). Photoelectrons were observed to peak along the laser polarization due to the ICR, but the anisotropy was the largest for p-BDC2–, followed by the m- and o-isomer. The observed anisotropy is related to the direction of the ICR or the detailed molecular structures, suggesting that photoelectron imaging may allow structural information to be obtained for complex multiply charged anions.

  11. Cleaning and activation of beryllium-copper electron multiplier dynodes.

    NASA Technical Reports Server (NTRS)

    Pongratz, M. B.

    1972-01-01

    Description of a cleaning and activation procedure followed in preparing beryllium-copper dynodes for electron multipliers used in sounding-rocket experiments to detect auroral electrons. The initial degreasing step involved a 5-min bath in trichloroethylene in an ultrasonic cleaner. This was followed by an ultrasonic rinse in methanol and by a two-step acid pickling treatment to remove the oxides. Additional rinsing in water and methanol was followed by activation in a stainless-steel RF induction oven.

  12. Mesh quality control for multiply-refined tetrahedral grids

    NASA Technical Reports Server (NTRS)

    Biswas, Rupak; Strawn, Roger

    1994-01-01

    A new algorithm for controlling the quality of multiply-refined tetrahedral meshes is presented in this paper. The basic dynamic mesh adaption procedure allows localized grid refinement and coarsening to efficiently capture aerodynamic flow features in computational fluid dynamics problems; however, repeated application of the procedure may significantly deteriorate the quality of the mesh. Results presented show the effectiveness of this mesh quality algorithm and its potential in the area of helicopter aerodynamics and acoustics.

  13. Study of the electric field inside microchannel plate multipliers

    SciTech Connect

    Gatti, E.; Oba, K.; Rehak, P.

    1982-01-01

    Electric field inside high gain microchannel plate multipliers was studied. The calculations were based directly on the solution of the Maxwell equations applied to the microchannel plate (MCP) rather than on the conventional lumped RC model. The results are important to explain the performance of MCP's, (1) under a pulsed bias tension and, (2) at high rate conditions. The results were tested experimentally and a new method of MCP operation free from the positive ion feedback was demonstrated.

  14. High performance pipelined multiplier with fast carry-save adder

    NASA Technical Reports Server (NTRS)

    Wu, Angus

    1990-01-01

    A high-performance pipelined multiplier is described. Its high performance results from the fast carry-save adder basic cell which has a simple structure and is suitable for the Gate Forest semi-custom environment. The carry-save adder computes the sum and carry within two gate delay. Results show that the proposed adder can operate at 200 MHz for a 2-micron CMOS process; better performance is expected in a Gate Forest realization.

  15. Comparison of indirect cost multipliers for vehicle manufacturing

    SciTech Connect

    Vyas, A.; Santini, D.; Cuenca, R.

    2000-05-16

    In the process of manufacturing and selling vehicles, a manufacturer incurs certain costs. Among these costs are those incurred directly as a part of manufacturing operations and those incurred indirectly in the processes of manufacturing and selling. The indirect costs may be production-related, such as R and D and engineering; business-related, such as corporate staff salaries and pensions; or retail-sales-related, such as dealer support and marketing. These indirect costs are recovered by allocating them to each vehicle. Under a stable, high-volume production process, the allocation of these indirect costs can be approximated as multipliers (or factors) applied to the direct cost of manufacturing. A manufacturer usually allocates indirect costs to finished vehicles according to a corporation-specific pricing strategy. Because the volumes of sales and production vary widely by model within a corporation, the internal corporate percent allocation of various accounting categories (such as profit or corporate overheat) can vary widely among individual models. Approaches also vary across corporations. For these purposes, an average value is constructed, by means of a generic representative method, for vehicle models produced at high volume. To accomplish this, staff at Argonne National Laboratory's (ANL's) Center for Transportation Research analyzed the conventional vehicle cost structure and developed indirect cost multipliers for passenger vehicles. This memorandum summarizes the results of an effort to compare and put on a common basis the cost multipliers used in ANL's electric and hybrid electric vehicle cost estimation procedures with those resulting from two other methodologies. One of the two compared methodologies is derived from a 1996 presentation by Dr. Chris Borroni-Bird of Chrysler Corporation, the other is by Energy and Environmental Analysis, Inc. (EEA), as described in a 1995 report by the Office of Technology Assessment (OTA), Congress of the United

  16. Number Words in Young Children's Conceptual and Procedural Knowledge of Addition, Subtraction and Inversion

    ERIC Educational Resources Information Center

    Canobi, Katherine H.; Bethune, Narelle E.

    2008-01-01

    Three studies addressed children's arithmetic. First, 50 3- to 5-year-olds judged physical demonstrations of addition, subtraction and inversion, with and without number words. Second, 20 3- to 4-year-olds made equivalence judgments of additions and subtractions. Third, 60 4- to 6-year-olds solved addition, subtraction and inversion problems that…

  17. Subtraction of Positive and Negative Numbers: The Difference and Completion Approaches with Chips

    ERIC Educational Resources Information Center

    Flores, Alfinio

    2008-01-01

    Diverse contexts such as "take away," comparison," and "completion" give rise to subtraction problems. The take-away interpretation of subtraction has been explored using two-colored chips to help students understand addition and subtraction of integers. This article illustrates how the difference and completion (or missing addend) interpretations…

  18. Female Stick Insects Mate Multiply to Find Compatible Mates.

    PubMed

    Arbuthnott, Devin; Crespi, Bernard J; Schwander, Tanja

    2015-10-01

    Why females of many species mate multiply in the absence of direct benefits remains an open question in evolutionary ecology. Interacting and mating with multiple males can be costly to females in terms of time, resources, predation risk, and disease transmission. A number of indirect genetic benefits have been proposed to explain such behaviors, but the relative importance of these mechanisms in natural systems remains unclear. We tested for several direct and indirect benefits of polyandry in the walking stick Timema cristinae. We found no evidence of direct benefits with respect to longevity or fecundity. However, male × female genotypic interactions affected egg-hatching success and offspring production independent of relatedness, suggesting that mating with certain males benefits females and that the best male may differ for each female. Furthermore, multiply mated females biased paternity toward one or few males, and the extent of this bias was positively correlated to egg-hatching success. Our data, therefore, provide evidence for indirect benefits through compatibility effects in this species. By mating multiply, females may improve their chances of mating with a compatible male if compatibility cannot be assessed before mating. Such compatibility effects can explain the evolution and maintenance of polyandry in Timema and many other species.

  19. Self-mixing differential vibrometer based on electronic channel subtraction.

    PubMed

    Donati, Silvano; Norgia, Michele; Giuliani, Guido

    2006-10-01

    An instrument for noncontact measurement of differential vibrations is developed, based on the self-mixing interferometer. As no reference arm is available in the self-mixing configuration, the differential mode is obtained by electronic subtraction of signals from two (nominally equal) vibrometer channels, taking advantage that channels are servo stabilized and thus insensitive to speckle and other sources of amplitude fluctuation. We show that electronic subtraction is nearly as effective as field superposition. Common-mode suppression is 25-30 dB, the dynamic range (amplitude) is in excess of 100 microm, and the minimum measurable (differential) amplitude is 20 nm on a B = 10 kHz bandwidth. The instrument has been used to measure vibrations of two metal samples kept in contact, revealing the hysteresis cycle in the microslip and gross-slip regimes, which are of interest in the study of friction induced vibration damping of gas turbine blades for aircraft applications.

  20. Removing Cardiac Artefacts in Magnetoencephalography with Resampled Moving Average Subtraction

    PubMed Central

    Ahlfors, Seppo P.; Hinrichs, Hermann

    2016-01-01

    Magnetoencephalography (MEG) signals are commonly contaminated by cardiac artefacts (CAs). Principle component analysis and independent component analysis have been widely used for removing CAs, but they typically require a complex procedure for the identification of CA-related components. We propose a simple and efficient method, resampled moving average subtraction (RMAS), to remove CAs from MEG data. Based on an electrocardiogram (ECG) channel, a template for each cardiac cycle was estimated by a weighted average of epochs of MEG data over consecutive cardiac cycles, combined with a resampling technique for accurate alignment of the time waveforms. The template was subtracted from the corresponding epoch of the MEG data. The resampling reduced distortions due to asynchrony between the cardiac cycle and the MEG sampling times. The RMAS method successfully suppressed CAs while preserving both event-related responses and high-frequency (>45 Hz) components in the MEG data. PMID:27503196

  1. ZAP - enhanced PCA sky subtraction for integral field spectroscopy

    NASA Astrophysics Data System (ADS)

    Soto, Kurt T.; Lilly, Simon J.; Bacon, Roland; Richard, Johan; Conseil, Simon

    2016-05-01

    We introduce Zurich Atmosphere Purge (ZAP), an approach to sky subtraction based on principal component analysis (PCA) that we have developed for the Multi Unit Spectrographic Explorer (MUSE) integral field spectrograph. ZAP employs filtering and data segmentation to enhance the inherent capabilities of PCA for sky subtraction. Extensive testing shows that ZAP reduces sky emission residuals while robustly preserving the flux and line shapes of astronomical sources. The method works in a variety of observational situations from sparse fields with a low density of sources to filled fields in which the target source fills the field of view. With the inclusion of both of these situations, the method is generally applicable to many different science cases and should also be useful for other instrumentation. ZAP is available for download at http://muse-vlt.eu/science/tools.

  2. Robust Background Subtraction with Foreground Validation for Urban Traffic Video

    SciTech Connect

    Cheung, S S; Kamath, C

    2004-01-15

    Identifying moving objects in a video sequence is a fundamental and critical task in many computer-vision applications. Background subtraction techniques are commonly used to separate foreground moving objects from the background. Most background subtraction techniques assume a single rate of adaptation, which is inadequate for complex scenes such as a traffic intersection where objects are moving at different and varying speeds. In this paper, we propose a foreground validation algorithm that first builds a foreground mask using a slow-adapting Kalman filter, and then validates individual foreground pixels by a simple moving object model, built using both the foreground and background statistics as well as the frame difference. Ground-truth experiments with urban traffic sequences show that our proposed algorithm significantly improves upon results using only Kalman filter or frame-differencing, and outperforms other techniques based on mixture of Gaussians, median filter, and approximated media filter.

  3. Realization of arithmetic addition and subtraction in a quantum system

    NASA Astrophysics Data System (ADS)

    Um, Mark; Zhang, Junhua; Lv, Dingshun; Lu, Yao; An, Shuoming; Zhang, Jing-Ning; Kim, Kihwan; Kim, M. S.; Nha, Hyunchul

    2015-05-01

    We report an experimental realization of the conventional arithmetic on a bosonic system, in particular, phonons of a 171Yb+ ion trapped in a harmonic potential. The conventional addition and subtraction are totally different from the quantum operations of creation ↠and annihilation â that have the modification of √{ n } factor due to the symmetric nature of bosons. In our realization, the addition and subtraction do not depend on the number of particles originally in the system and nearly deterministically bring a classical state into a non-classical state. We implement such operations by applying the scheme of transitionless shortcuts to adiabaticity on anti-Jaynes-Cummings transition. This technology enables quantum state engineering and can be applied to many other experimental platforms. This work was supported by the National Basic Research Program of China under Grants No. 2011CBA00300 (No. 2011CBA00301), the National Natural Science Foundation of China 11374178.

  4. Digital subtraction angiography in pediatric cerebrovascular occlusive disease

    SciTech Connect

    Faerber, E.N.; Griska, L.A.B.; Swartz, J.D.; Capitanio, M.A.; Popky, G.L.

    1984-08-01

    While conventional angiography has been used to demonstrate cerebrovascular occlusive disease in the past, digital subtraction angiography (DSA) is capable of showing progressive vascular involvement with ease, simplicity, and extremely low morbidity, making it particularly well suited for children and outpatients either alone or coordinated with computed tomography. The authors discuss the usefulness and advantages of DSA as demonstrated in 7 infants and children with hemiplegia, 4 of whom had sickle-cell disease.

  5. Subtraction Radiography for the Diagnosis of Bone Lesions in Dogs.

    DTIC Science & Technology

    1984-05-31

    Avail ander Journal of Periodontology Dist Special Ř 211 East Chicago Avenue Room 924 Chicago, IL 60611 Dear Sirs: I m submitting an original...research article titled "Subtraction Radiography for the Diagnosis of Bone Lesions in Dogs" solely to the Journal of Periodontology for review and... clinical practice in our area. 60-70 Kvp would have produced more contrast in the radiographic films used for the conventional technique, but likely

  6. Subtractive Renormalization Group Invariance: Pionless EFT at NLO

    SciTech Connect

    Timoteo, Varese S.; Szpigel, Sergio; Duraes, Francisco O.

    2010-11-12

    We show some results concerning the renormalization group (RG) invariance of the nucleon-nucleon (NN) interaction in pionless effective field theory at next-to-leading order (NLO), using a non-relativistic Callan-Symanzik equation (NRCS) for the driving term of the Lippmann-Schwinger (LS) equation with three recursive subtractions. The phase-shifts obtained for the RG evolved potential are same as those for the original potential, apart from relative differences of order 10{sup -15}.

  7. Subtractive Renormalization Group Invariance: Pionless EFT at NLO

    NASA Astrophysics Data System (ADS)

    Timóteo, Varese S.; Szpigel, Sérgio; Durães, Francisco O.

    2010-11-01

    We show some results concerning the renormalization group (RG) invariance of the nucleon-nucleon (NN) interaction in pionless effective field theory at next-to-leading order (NLO), using a non-relativistic Callan-Symanzik equation (NRCS) for the driving term of the Lippmann-Schwinger (LS) equation with three recursive subtractions. The phase-shifts obtained for the RG evolved potential are same as those for the original potential, apart from relative differences of order 10-15.

  8. ROBUST TECHNIQUES FOR BACKGROUND SUBTRACTION IN URBAN TRAFFIC VIDEO

    SciTech Connect

    Kamath, C; Cheung, S S

    2003-10-28

    Identifying moving objects from a video sequence is a fundamental and critical task in many computer-vision applications. A common approach is to perform background subtraction, which identifies moving objects from the portion of a video frame that differs significantly from a background model. There are many challenges in developing a good background subtraction algorithm. First, it must be robust against changes in illumination. Second, it should avoid detecting non-stationary background objects such as swinging leaves, rain, snow, and shadow cast by moving objects. Finally, its internal background model should react quickly to changes in background such as starting and stopping of vehicles. In this paper, we compare various background subtraction algorithms for detecting moving vehicles and pedestrians in urban traffic video sequences. We consider approaches varying from simple techniques such as frame differencing and adaptive median filtering, to more sophisticated probabilistic modeling techniques. While complicated techniques often produce superior performance, our experiments show that simple techniques such as adaptive median filtering can produce good results with much lower computational complexity.

  9. Addition and subtraction in wild New Zealand robins.

    PubMed

    Garland, Alexis; Low, Jason

    2014-11-01

    This experiment aimed to investigate proto-arithmetic ability in a wild population of New Zealand robins. We investigated numerical competence from the context of computation: behavioural responses to arithmetic operations over small numbers of prey objects (mealworms). Robins' behavioural responses (such as search time) to the simple addition and subtraction problems presented in a Violation of Expectancy (VoE) paradigm were measured. Either a congruent (expected) or incongruent (unexpected) quantity of food items were hidden in a trap door out of view of the subject. Within view of the subject, a quantity of items were added into (and in some cases subtracted from) the apparatus which was either the same as that hidden, or different. Robins were then allowed them to find a quantity that either preserved or violated addition and subtraction outcomes. Robins searched around the apparatus longer when presented with an incongruent scenario violating arithmetic rules, demonstrating potential proto-arithmetic awareness of changes in prey quantity. This article is part of a Special Issue entitled: Cognition in the wild.

  10. Temporal subtraction contrast-enhanced dedicated breast CT

    NASA Astrophysics Data System (ADS)

    Gazi, Peymon M.; Aminololama-Shakeri, Shadi; Yang, Kai; Boone, John M.

    2016-09-01

    The development of a framework of deformable image registration and segmentation for the purpose of temporal subtraction contrast-enhanced breast CT is described. An iterative histogram-based two-means clustering method was used for the segmentation. Dedicated breast CT images were segmented into background (air), adipose, fibroglandular and skin components. Fibroglandular tissue was classified as either normal or contrast-enhanced then divided into tiers for the purpose of categorizing degrees of contrast enhancement. A variant of the Demons deformable registration algorithm, intensity difference adaptive Demons (IDAD), was developed to correct for the large deformation forces that stemmed from contrast enhancement. In this application, the accuracy of the proposed method was evaluated in both mathematically-simulated and physically-acquired phantom images. Clinical usage and accuracy of the temporal subtraction framework was demonstrated using contrast-enhanced breast CT datasets from five patients. Registration performance was quantified using normalized cross correlation (NCC), symmetric uncertainty coefficient, normalized mutual information (NMI), mean square error (MSE) and target registration error (TRE). The proposed method outperformed conventional affine and other Demons variations in contrast enhanced breast CT image registration. In simulation studies, IDAD exhibited improvement in MSE (0-16%), NCC (0-6%), NMI (0-13%) and TRE (0-34%) compared to the conventional Demons approaches, depending on the size and intensity of the enhancing lesion. As lesion size and contrast enhancement levels increased, so did the improvement. The drop in the correlation between the pre- and post-contrast images for the largest enhancement levels in phantom studies is less than 1.2% (150 Hounsfield units). Registration error, measured by TRE, shows only submillimeter mismatches between the concordant anatomical target points in all patient studies. The algorithm was

  11. Auditing the multiply-related concepts within the UMLS

    PubMed Central

    Mougin, Fleur; Grabar, Natalia

    2014-01-01

    Objective This work focuses on multiply-related Unified Medical Language System (UMLS) concepts, that is, concepts associated through multiple relations. The relations involved in such situations are audited to determine whether they are provided by source vocabularies or result from the integration of these vocabularies within the UMLS. Methods We study the compatibility of the multiple relations which associate the concepts under investigation and try to explain the reason why they co-occur. Towards this end, we analyze the relations both at the concept and term levels. In addition, we randomly select 288 concepts associated through contradictory relations and manually analyze them. Results At the UMLS scale, only 0.7% of combinations of relations are contradictory, while homogeneous combinations are observed in one-third of situations. At the scale of source vocabularies, one-third do not contain more than one relation between the concepts under investigation. Among the remaining source vocabularies, seven of them mainly present multiple non-homogeneous relations between terms. Analysis at the term level also shows that only in a quarter of cases are the source vocabularies responsible for the presence of multiply-related concepts in the UMLS. These results are available at: http://www.isped.u-bordeaux2.fr/ArticleJAMIA/results_multiply_related_concepts.aspx. Discussion Manual analysis was useful to explain the conceptualization difference in relations between terms across source vocabularies. The exploitation of source relations was helpful for understanding why some source vocabularies describe multiple relations between a given pair of terms. PMID:24464853

  12. ProADD: A database on Protein Aggregation Diseases

    PubMed Central

    Shobana, Ramesh; Pandaranayaka, Eswari PJ

    2014-01-01

    ProADD, a database for protein aggregation diseases, is developed to organize the data under a single platform to facilitate easy access for researchers. Diseases caused due to protein aggregation and the proteins involved in each of these diseases are integrated. The database helps in classification of proteins involved in the protein aggregation diseases based on sequence and structural analysis. Analysis of proteins can be done to mine patterns prevailing among the aggregating proteins. Availability http://bicmku.in/ProADD PMID:25097386

  13. Magnetic states in multiply-connected flat nanoelements

    NASA Astrophysics Data System (ADS)

    Bogatyrev, Andrei B.; Metlov, Konstantin L.

    2015-10-01

    Flat magnetic nanoelements are an essential component of current and future spintronic devices. By shaping an element it is possible to select and stabilize chosen metastable magnetic states, control its magnetization dynamics. Here, using a recent significant development in mathematics of conformal mapping, complex variable based approach to the description of magnetic states in planar nanoelements is extended to the case when elements are multiply-connected (that is, contain holes or magnetic antidots). We show that presence of holes implies a certain restriction on the set of magnetic states of nanoelement.

  14. Monolithic millimeter-wave diode grid frequency multiplier arrays

    NASA Technical Reports Server (NTRS)

    Liu, Hong-Xia L.; Qin, X.-H.; Sjogren, L. B.; Wu, W.; Chung, E.; Domier, C. W.; Luhmann, N. C., Jr.

    1992-01-01

    Monolithic diode frequency multiplier arrays, including barrier-N-N(+) (BNN) doubler, multi-quantum-barrier-varactor (MQBV) tripler, Schottky-quantum-barrier-varactor (SQBV) tripler, and resonant-tunneling-diode (RTD) tripler arrays, have been successfully fabricated with yields between 85 and 99 percent. Frequency doubling and/or tripling have been observed for all the arrays. Output powers of 2.4-2.6 W (eta = 10-18 percent) at 66 GHz with the BNN doubler and 3.8-10 W (eta = 1.7-4 percent) at 99 GHz with the SQBV tripler have been achieved.

  15. Multiply-agile encryption in high speed communication networks

    SciTech Connect

    Pierson, L.G.; Witzke, E.L.

    1997-05-01

    Different applications have different security requirements for data privacy, data integrity, and authentication. Encryption is one technique that addresses these requirements. Encryption hardware, designed for use in high-speed communications networks, can satisfy a wide variety of security requirements if that hardware is key-agile, robustness-agile and algorithm-agile. Hence, multiply-agile encryption provides enhanced solutions to the secrecy, interoperability and quality of service issues in high-speed networks. This paper defines these three types of agile encryption. Next, implementation issues are discussed. While single-algorithm, key-agile encryptors exist, robustness-agile and algorithm-agile encryptors are still research topics.

  16. An Accelerated Linearized Alternating Direction Method of Multipliers

    DTIC Science & Technology

    2014-02-01

    The idea of analyzing (1.8) in order to solve (1.1) is essentially the augmented Lagrangian method ( ALM ) by Hestenes [26] and Powell [44] (It is...originally called the method of multipliers in [26, 44]; see also the textbooks, e.g., [5, 41, 6]). The ALM is a special case of the Douglas-Rachford...splitting method [19, 16, 32], which is also an instance of the proximal point algorithm [17, 46]. The iteration complexity of an inexact version of ALM

  17. Calculation evaluation of multiplying properties of LWR with thorium fuel

    NASA Astrophysics Data System (ADS)

    Shamanin, I. V.; Grachev, V. M.; Knyshev, V. V.; Bedenko, S. V.; Novikova, N. G.

    2017-01-01

    The results of multiplying properties design research of the unit cell and LWR fuel assembly with the high temperature gas-cooled thorium reactor fuel pellet are presented in the work. The calculation evaluation showed the possibility of using thorium in LWR effectively. In this case the amount of fissile isotope is 2.45 times smaller in comparison with the standard loading of LWR. The research and numerical experiments were carried out using the verified accounting code of the program MCU5, modern libraries of evaluated nuclear data and multigroup approximations.

  18. Convergence of a Substructuring Method with LaGrange Multipliers

    NASA Technical Reports Server (NTRS)

    Mandel, Jan; Tezaur, Radek

    1996-01-01

    We analyze the convergence of a substructuring iterative method with Lagrange multipliers, proposed recently by Farhat and Roux. The method decomposes finite element discretization of an elliptic boundary value problem into Neumann problems on the subdomains and a coarse problem for the subdomain nullspace components. For linear conforming elements and preconditioning by the Dirichlet problems on the subdomains, we prove the asymptotic bound on the condition number C(1 + log(H/h))(sup gamma), gamma = 2 or 3, where h is the characteristic element size and H is the subdomain size.

  19. Maternal MCG Interference Cancellation Using Splined Independent Component Subtraction

    PubMed Central

    Yu, Suhong

    2011-01-01

    Signal distortion is commonly observed when using independent component analysis (ICA) to remove maternal cardiac interference from the fetal magnetocardiogram. This can be seen even in the most conservative case where only the independent components dominated by maternal interference are subtracted from the raw signal, a procedure we refer to as independent component subtraction (ICS). Distortion occurs when the subspaces of the fetal and maternal signals have appreciable overlap. To overcome this problem, we employed splining to remove the fetal signal from the maternal source component. The maternal source components were downsampled and then interpolated to their original sampling rate using a cubic spline. A key aspect of the splining procedure is that the maternal QRS complexes are downsampled much less than the rest of the maternal signal so that they are not distorted, despite their higher bandwidth. The splined maternal source components were projected back onto the magnetic field measurement space and then subtracted from the raw signal. The method was evaluated using data from 24 subjects. We compared the results of conventional, i.e., unsplined, ICS with our method, splined ICS, using matched filtering as a reference. Correlation and subjective assessment of the P-wave and QRS complex were used to assess the performance. Using ICS, we found that the P-wave was adversely affected in 7 of 24 (29%) subjects, all having correlations less than 0.8. Splined ICS showed negligible distortion and improved the signal fidelity to some extent in all subjects. We also demonstrated that maternal T-wave interference could be problematic when the fetal and maternal heartbeats were synchronous. In these instances, splined ICS was more effective than matched filtering. PMID:21712157

  20. Suppressive Subtractive Hybridization Detects Extensive Genomic Diversity in Thermotoga maritima

    PubMed Central

    Nesbø, Camilla L.; Nelson, Karen E.; Doolittle, W. Ford

    2002-01-01

    Comparisons between genomes of closely related bacteria often show large variations in gene content, even between strains of the same species. Such studies have focused mainly on pathogens; here, we examined Thermotoga maritima, a free-living hyperthermophilic bacterium, by using suppressive subtractive hybridization. The genome sequence of T. maritima MSB8 is available, and DNA from this strain served as a reference to obtain strain-specific sequences from Thermotoga sp. strain RQ2, a very close relative (∼96% identity for orthologous protein-coding genes, 99.7% identity in the small-subunit rRNA sequence). Four hundred twenty-six RQ2 subtractive clones were sequenced. One hundred sixty-six had no DNA match in the MSB8 genome. These differential clones comprise, in sum, 48 kb of RQ2-specific DNA and match 72 genes in the GenBank database. From the number of identical clones, we estimated that RQ2 contains 350 to 400 genes not found in MSB8. Assuming a similar genome size, this corresponds to 20% of the RQ2 genome. A large proportion of the RQ2-specific genes were predicted to be involved in sugar transport and polysaccharide degradation, suggesting that polysaccharides are more important as nutrients for this strain than for MSB8. Several clones encode proteins involved in the production of surface polysaccharides. RQ2 encodes multiple subunits of a V-type ATPase, while MSB8 possesses only an F-type ATPase. Moreover, an RQ2-specific MutS homolog was found among the subtractive clones and appears to belong to a third novel archaeal type MutS lineage. Southern blot analyses showed that some of the RQ2 differential sequences are found in some other members of the order Thermotogales, but the distribution of these variable genes is patchy, suggesting frequent lateral gene transfer within the group. PMID:12142418

  1. Adding and subtracting vectors: The problem with the arrow representation

    NASA Astrophysics Data System (ADS)

    Heckler, Andrew F.; Scaife, Thomas M.

    2015-06-01

    A small number of studies have investigated student understanding of vector addition and subtraction in generic or introductory physics contexts, but in almost all cases the questions posed were in the vector arrow representation. In a series of experiments involving over 1000 students and several semesters, we investigated student understanding of vector addition and subtraction in both the arrow and algebraic notation (using i ^, j ^, k ^) in generic mathematical and physics contexts. First, we replicated a number of previous findings of student difficulties in the arrow format and discovered several additional difficulties, including the finding that different relative arrow orientations can prompt different solution paths and different kinds of mistakes, which suggests that students need to practice with a variety of relative orientations. Most importantly, we found that average performance in the i j k format was typically excellent and often much better than performance in the arrow format in either the generic or physics contexts. Further, while we find that the arrow format tends to prompt students to a more physically intuitive solution path, we also find that, when prompted, student solutions in the i j k format also display significant physical insights into the problem. We also find a hierarchy in correct answering between the two formats, with correct answering in the i j k format being more fundamental than for the arrow format. Overall, the results suggest that many student difficulties with these simple vector problems lie with the arrow representation itself. For instruction, these results imply that introducing the i j k notation (or some equivalent) with the arrow notation concurrently may be a very useful way to improve student performance as well as help students to learn physics concepts involving vector addition and subtraction.

  2. Quantitative Digital Subtraction Angiography in Pediatric Moyamoya Disease

    PubMed Central

    2015-01-01

    Moyamoya disease is a unique cerebrovascular disorder characterized by idiopathic progressive stenosis at the terminal portion of the internal carotid artery (ICA) and fine vascular network. The aim of this review is to present the clinical application of quantitative digital subtraction angiography (QDSA) in pediatric moyamoya disease. Using conventional angiographic data and postprocessing software, QDSA provides time-contrast intensity curves and then displays the peak time (Tmax) and area under the curve (AUC). These parameters of QDSA can be used as surrogate markers for the hemodynamic evaluation of disease severity and quantification of postoperative neovascularization in moyamoya disease. PMID:26180611

  3. Peripheral NN scattering from subtractive renormalization of chiral interactions

    SciTech Connect

    Batista, E. F.; Szpigel, S.; Timóteo, V. S.

    2014-11-11

    We apply five subtractions in the Lippman-Schwinger (LS) equation in order to perform a non-perturbative renormalization of chiral N3LO nucleon-nucleon interactions. Here we compute the phase shifts for the uncoupled peripheral waves at renormalization scales between 0.1 fm{sup −1} and 1 fm{sup −1}. In this range, the results are scale invariant and provide an overall good agreement with the Nijmegen partial wave analysis up to at least E{sub lab} = 150 MeV, with a cutoff at Λ = 30 fm{sup −1}.

  4. WFPC2 photometry from subtraction of TinyTim PSFs

    NASA Technical Reports Server (NTRS)

    Remy, M.; Surdej, J.; Baggett, S.; Wiggs, M.

    1997-01-01

    Based upon the subtraction of TinyTim Point Spread Function (PSFs) from Principle Component Image (PC1) point-like objects, a method has been developed to determine the optimal values for the telescope jitter and the Z4 relative focus during calibration or science observations. Using these jitter and focus values, an optimal TinyTim PSF, computed over a resampled grid, is then iteratively fitted to the object, yielding an improvement in the PSF centering, more accurate photometric results and a better detection of underlying structures. Preliminary results seem to indicate that appropriate synthetic TinyTim PSFs perform as well as observed PSFs.

  5. Addition and subtraction by students with Down syndrome

    NASA Astrophysics Data System (ADS)

    Noda Herrera, Aurelia; Bruno, Alicia; González, Carina; Moreno, Lorenzo; Sanabria, Hilda

    2011-01-01

    We present a research report on addition and subtraction conducted with Down syndrome students between the ages of 12 and 31. We interviewed a group of students with Down syndrome who executed algorithms and solved problems using specific materials and paper and pencil. The results show that students with Down syndrome progress through the same procedural levels as those without disabilities though they have difficulties in reaching the most abstract level (numerical facts). The use of fingers or concrete representations (balls) appears as a fundamental process among these students. As for errors, these vary widely depending on the students, and can be attributed mostly to an incomplete knowledge of the decimal number system.

  6. Additive and subtractive scrambling in optional randomized response modeling.

    PubMed

    Hussain, Zawar; Al-Sobhi, Mashail M; Al-Zahrani, Bander

    2014-01-01

    This article considers unbiased estimation of mean, variance and sensitivity level of a sensitive variable via scrambled response modeling. In particular, we focus on estimation of the mean. The idea of using additive and subtractive scrambling has been suggested under a recent scrambled response model. Whether it is estimation of mean, variance or sensitivity level, the proposed scheme of estimation is shown relatively more efficient than that recent model. As far as the estimation of mean is concerned, the proposed estimators perform relatively better than the estimators based on recent additive scrambling models. Relative efficiency comparisons are also made in order to highlight the performance of proposed estimators under suggested scrambling technique.

  7. A Highly Linear and Wide Input Range Four-Quadrant CMOS Analog Multiplier Using Active Feedback

    NASA Astrophysics Data System (ADS)

    Huang, Zhangcai; Jiang, Minglu; Inoue, Yasuaki

    Analog multipliers are one of the most important building blocks in analog signal processing circuits. The performance with high linearity and wide input range is usually required for analog four-quadrant multipliers in most applications. Therefore, a highly linear and wide input range four-quadrant CMOS analog multiplier using active feedback is proposed in this paper. Firstly, a novel configuration of four-quadrant multiplier cell is presented. Its input dynamic range and linearity are improved significantly by adding two resistors compared with the conventional structure. Then based on the proposed multiplier cell configuration, a four-quadrant CMOS analog multiplier with active feedback technique is implemented by two operational amplifiers. Because of both the proposed multiplier cell and active feedback technique, the proposed multiplier achieves a much wider input range with higher linearity than conventional structures. The proposed multiplier was fabricated by a 0.6µm CMOS process. Experimental results show that the input range of the proposed multiplier can be up to 5.6Vpp with 0.159% linearity error on VX and 4.8Vpp with 0.51% linearity error on VY for ±2.5V power supply voltages, respectively.

  8. Interatomic Coulombic decay cascades in multiply excited neon clusters

    PubMed Central

    Nagaya, K.; Iablonskyi, D.; Golubev, N. V.; Matsunami, K.; Fukuzawa, H.; Motomura, K.; Nishiyama, T.; Sakai, T.; Tachibana, T.; Mondal, S.; Wada, S.; Prince, K. C.; Callegari, C.; Miron, C.; Saito, N.; Yabashi, M.; Demekhin, Ph. V.; Cederbaum, L. S.; Kuleff, A. I.; Yao, M.; Ueda, K.

    2016-01-01

    In high-intensity laser light, matter can be ionized by direct multiphoton absorption even at photon energies below the ionization threshold. However on tuning the laser to the lowest resonant transition, the system becomes multiply excited, and more efficient, indirect ionization pathways become operative. These mechanisms are known as interatomic Coulombic decay (ICD), where one of the species de-excites to its ground state, transferring its energy to ionize another excited species. Here we show that on tuning to a higher resonant transition, a previously unknown type of interatomic Coulombic decay, intra-Rydberg ICD occurs. In it, de-excitation of an atom to a close-lying Rydberg state leads to electron emission from another neighbouring Rydberg atom. Moreover, systems multiply excited to higher Rydberg states will decay by a cascade of such processes, producing even more ions. The intra-Rydberg ICD and cascades are expected to be ubiquitous in weakly-bound systems exposed to high-intensity resonant radiation. PMID:27917867

  9. Interatomic Coulombic decay cascades in multiply excited neon clusters

    NASA Astrophysics Data System (ADS)

    Nagaya, K.; Iablonskyi, D.; Golubev, N. V.; Matsunami, K.; Fukuzawa, H.; Motomura, K.; Nishiyama, T.; Sakai, T.; Tachibana, T.; Mondal, S.; Wada, S.; Prince, K. C.; Callegari, C.; Miron, C.; Saito, N.; Yabashi, M.; Demekhin, Ph. V.; Cederbaum, L. S.; Kuleff, A. I.; Yao, M.; Ueda, K.

    2016-12-01

    In high-intensity laser light, matter can be ionized by direct multiphoton absorption even at photon energies below the ionization threshold. However on tuning the laser to the lowest resonant transition, the system becomes multiply excited, and more efficient, indirect ionization pathways become operative. These mechanisms are known as interatomic Coulombic decay (ICD), where one of the species de-excites to its ground state, transferring its energy to ionize another excited species. Here we show that on tuning to a higher resonant transition, a previously unknown type of interatomic Coulombic decay, intra-Rydberg ICD occurs. In it, de-excitation of an atom to a close-lying Rydberg state leads to electron emission from another neighbouring Rydberg atom. Moreover, systems multiply excited to higher Rydberg states will decay by a cascade of such processes, producing even more ions. The intra-Rydberg ICD and cascades are expected to be ubiquitous in weakly-bound systems exposed to high-intensity resonant radiation.

  10. Low voltage electron multiplying CCD in a CMOS process

    NASA Astrophysics Data System (ADS)

    Dunford, Alice; Stefanov, Konstantin; Holland, Andrew

    2016-07-01

    Low light level and high-speed image sensors as required for space applications can suffer from a decrease in the signal to noise ratio (SNR) due to the photon-starved environment and limitations of the sensor's readout noise. The SNR can be increased by the implementation of Time Delay Integration (TDI) as it allows photoelectrons from multiple exposures to be summed in the charge domain with no added noise. Electron Multiplication (EM) can further improve the SNR and lead to an increase in device performance. However, both techniques have traditionally been confined to Charge Coupled Devices (CCD) due to the efficient charge transfer required. With the increase in demand for CMOS sensors with equivalent or superior functionality and performance, this paper presents findings from the characterisation of a low voltage EMCCD in a CMOS process using advanced design features to increase the electron multiplying gain. By using the CMOS process, it is possible to increase chip integration and functionality and achieve higher readout speeds and reduced pixel size. The presented characterisation results include analysis of the photon transfer curve, the dark current, the electron multiplying gain and analysis of the parameters' dependence on temperature and operating voltage.

  11. Multiplying optical tweezers force using a micro-lever.

    PubMed

    Lin, Chih-Lang; Lee, Yi-Hsiung; Lin, Chin-Te; Liu, Yi-Jui; Hwang, Jiann-Lih; Chung, Tien-Tung; Baldeck, Patrice L

    2011-10-10

    This study presents a photo-driven micro-lever fabricated to multiply optical forces using the two-photon polymerization 3D-microfabrication technique. The micro-lever is a second class lever comprising an optical trapping sphere, a beam, and a pivot. A micro-spring is placed between the short and long arms to characterize the induced force. This design enables precise manipulation of the micro-lever by optical tweezers at the micron scale. Under optical dragging, the sphere placed on the lever beam moves, resulting in torque that induces related force on the spring. The optical force applied at the sphere is approximately 100 to 300 pN, with a laser power of 100 to 300 mW. In this study, the optical tweezers drives the micro-lever successfully. The relationship between the optical force and the spring constant can be determined by using the principle of leverage. The arm ratio design developed in this study multiplies the applied optical force by 9. The experimental results are in good agreement with the simulation of spring property.

  12. Compliant displacement-multiplying apparatus for microelectromechanical systems

    DOEpatents

    Kota, Sridhar; Rodgers, M. Steven; Hetrick, Joel A.

    2001-01-01

    A pivotless compliant structure is disclosed that can be used to increase the geometric advantage or mechanical advantage of a microelectromechanical (MEM) actuator such as an electrostatic comb actuator, a capacitive-plate electrostatic actuator, or a thermal actuator. The compliant structure, based on a combination of interconnected flexible beams and cross-beams formed of one or more layers of polysilicon or silicon nitride, can provide a geometric advantage of from about 5:1 to about 60:1 to multiply a 0.25-3 .mu.m displacement provided by a short-stroke actuator so that such an actuator can be used to generate a displacement stroke of about 10-34 .mu.m to operate a ratchet-driven MEM device or a microengine. The compliant structure has less play than conventional displacement-multiplying devices based on lever arms and pivoting joints, and is expected to be more reliable than such devices. The compliant structure and an associated electrostatic or thermal actuator can be formed on a common substrate (e.g. silicon) using surface micromachining.

  13. Enhancing Teaching using MATLAB Add-Ins for Excel

    ERIC Educational Resources Information Center

    Hamilton, Paul V.

    2004-01-01

    In this paper I will illustrate how to extend the capabilities of Microsoft Excel spreadsheets with add-ins created by MATLAB. Excel provides a broad array of fundamental tools but often comes up short when more sophisticated scenarios are involved. To overcome this short-coming of Excel while retaining its ease of use, I will describe how…

  14. Four Simple Ways to Add Movement in Daily Lessons

    ERIC Educational Resources Information Center

    Helgeson, John

    2011-01-01

    Adding movement to classroom activities not only engages students, but also may improve the classroom climate and reduce disruptions. In this article, the author discusses four simple activities to add movement in daily lessons. These activities are: (1) Vocabulary/Notes around the Room; (2) Cooperative Learning: Posting Task Assignments; (3)…

  15. Accommodating College Students with Learning Disabilities: ADD, ADHD, and Dyslexia

    ERIC Educational Resources Information Center

    Vickers, Melana Zyla

    2010-01-01

    Universities are providing extra time on tests, quiet exam rooms, in-class note-takers, and other assistance to college students with modest learning disabilities. But these policies are shrouded in secrecy. This paper, "Accommodating College Students with Learning Disabilities: ADD, ADHD, and Dyslexia," by Melana Zyla Vickers, examines…

  16. Medicalised Pupils: The Case of ADD/ADHD

    ERIC Educational Resources Information Center

    Kristjansson, Kristjan

    2009-01-01

    Recent decades have seen an increasing number of life's problems conceptualised and interpreted through the prism of disease; among them are those affecting pupils at school. Witness the cases of hyperactivity and deficient attention, so often diagnosed as ADD/ADHD. Research indicates that there is at least some tendency towards overdiagnosis of…

  17. Water Softeners: How Much Sodium Do They Add?

    MedlinePlus

    ... healthy eating I'm trying to watch the sodium in my diet. Should I be concerned about sodium from water softeners? Answers from Sheldon G. Sheps, M.D. Regular tap water contains very little sodium. The amount of sodium a water softener adds ...

  18. Face equipment lighting: integrated vs. add-on

    SciTech Connect

    Scott, F.E.

    1982-10-01

    The problems of providing lighting on face equipment are examined. In the US, some equipment manufacturers are building-in lighting systems to their machinery; others will install lighting systems as add-on or retrofitted items. The pros and cons of each method are examined and the views of manufacturers are quoted.

  19. Mode-routed fiber-optic add-drop filter

    NASA Technical Reports Server (NTRS)

    Moslehi, Behzad (Inventor); Black, Richard James (Inventor); Shaw, Herbert John (Inventor)

    2000-01-01

    New elements mode-converting two-mode grating and mode-filtering two-mode coupler are disclosed and used as elements in a system for communications, add-drop filtering, and strain sensing. Methods of fabrication for these new two-mode gratings and mode-filtering two-mode couplers are also disclosed.

  20. ADD and ADHD: An Overview for School Counselors. ERIC Digest.

    ERIC Educational Resources Information Center

    Pledge, Deanna S.

    School counselors are often consultants for parents and teachers on problems that children and adolescents face. Attention deficit disorder (ADD) is one such problem. It is frequently misunderstood, presenting a challenge for parents and teachers alike. The counselor is a resource for initial identification and interventions at home and in the…

  1. Serving Students Diagnosed with ADD: Avoiding Deficits in Professional Attention.

    ERIC Educational Resources Information Center

    Stoner, Gary; Carey, Sean P.

    1992-01-01

    Responds to previous article (Hakola, this issue) on legal rights of students with Attention Deficit Disorder (ADD). Presents contrasting perspective on educational services for children diagnosed with Attention Deficit Hyperactivity Disorder, linked more closely to professional research and practice than to law. Concerns discussed are grounded in…

  2. Meeting Learning Challenges: Working with the Child Who Has ADD

    ERIC Educational Resources Information Center

    Greenspan, Stanley I.

    2006-01-01

    The terms ADD (Attention Deficit Disorder) and ADHD (Attention Deficit Hyperactivity Disorder) are applied to several symptoms, including: difficulty in paying attention, distractibility, having a hard time following through on things, and sometimes over-activity and impulsivity. There are many different reasons why children have these symptoms.…

  3. Diamond Heat-Spreader for Submillimeter-Wave Frequency Multipliers

    NASA Technical Reports Server (NTRS)

    Lin, Robert H.; Schlecht, Erich T.; Chattopadhyay, Goutam; Gill, John J.; Mehdi, Imran; Siegel, Peter H.; Ward, John S.; Lee, Choonsup; Thomas, Bertrand C.; Maestrini, Alain

    2010-01-01

    The planar GaAs Shottky diode frequency multiplier is a critical technology for the local oscillator (LO) for submillimeter- wave heterodyne receivers due to low mass, tenability, long lifetime, and room-temperature operation. The use of a W-band (75-100 GHz) power amplifier followed by a frequency multiplier is the most common for submillimeter-wave sources. Its greatest challenge is to provide enough input power to the LO for instruments onboard future planetary missions. Recently, JPL produced 800 mW at 92.5 GHz by combining four MMICs in parallel in a balanced configuration. As more power at W-band is available to the multipliers, their power-handling capability be comes more important. High operating temperatures can lead to degradation of conversion efficiency or catastrophic failure. The goal of this innovation is to reduce the thermal resistance by attaching diamond film as a heat-spreader on the backside of multipliers to improve their power-handling capability. Polycrystalline diamond is deposited by hot-filament chemical vapor deposition (CVD). This diamond film acts as a heat-spreader to both the existing 250- and 300-GHz triplers, and has a high thermal conductivity (1,000-1,200 W/mK). It is approximately 2.5 times greater than copper (401 W/mK) and 20 times greater than GaAs (46 W/mK). It is an electrical insulator (resistivity approx. equals 10(exp 15) Ohms-cm), and has a low relative dielectric constant of 5.7. Diamond heat-spreaders reduce by at least 200 C at 250 mW of input power, compared to the tripler without diamond, according to thermal simulation. This superior thermal management provides a 100-percent increase in power-handling capability. For example, with this innovation, 40-mW output power has been achieved from a 250-GHz tripler at 350-mW input power, while the previous triplers, without diamond, suffered catastrophic failures. This breakthrough provides a stepping-stone for frequency multipliers-based LO up to 3 THz. The future work

  4. Four-Quadrant Analog Multipliers Using G4-FETs

    NASA Technical Reports Server (NTRS)

    Mojarradi, Mohammad; Blalock, Benjamin; Christoloveanu, Sorin; Chen, Suheng; Akarvardar, Kerem

    2006-01-01

    Theoretical analysis and some experiments have shown that the silicon-on-insulator (SOI) 4-gate transistors known as G4-FETs can be used as building blocks of four-quadrant analog voltage multiplier circuits. Whereas a typical prior analog voltage multiplier contains between six and 10 transistors, it is possible to construct a superior voltage multiplier using only four G4-FETs. A G4-FET is a combination of a junction field-effect transistor (JFET) and a metal oxide/semiconductor field-effect transistor (MOSFET). It can be regarded as a single transistor having four gates, which are parts of a structure that affords high functionality by enabling the utilization of independently biased multiple inputs. The structure of a G4-FET of the type of interest here (see Figure 1) is that of a partially-depleted SOI MOSFET with two independent body contacts, one on each side of the channel. The drain current comprises of majority charge carriers flowing from one body contact to the other that is, what would otherwise be the side body contacts of the SOI MOSFET are used here as the end contacts [the drain (D) and the source (S)] of the G4-FET. What would otherwise be the source and drain of the SOI MOSFET serve, in the G4-FET, as two junction-based extra gates (JG1 and JG2), which are used to squeeze the channel via reverse-biased junctions as in a JFET. The G4-FET also includes a polysilicon top gate (G1), which plays the same role as does the gate in an accumulation-mode MOSFET. The substrate emulates a fourth MOS gate (G2). By making proper choices of G4-FET device parameters in conjunction with bias voltages and currents, one can design a circuit in which two input gate voltages (Vin1,Vin2) control the conduction characteristics of G4-FETs such that the output voltage (Vout) closely approximates a value proportional to the product of the input voltages. Figure 2 depicts two such analog multiplier circuits. In each circuit, there is the following: The input and output

  5. Motion compensation in digital subtraction angiography using graphics hardware.

    PubMed

    Deuerling-Zheng, Yu; Lell, Michael; Galant, Adam; Hornegger, Joachim

    2006-07-01

    An inherent disadvantage of digital subtraction angiography (DSA) is its sensitivity to patient motion which causes artifacts in the subtraction images. These artifacts could often reduce the diagnostic value of this technique. Automated, fast and accurate motion compensation is therefore required. To cope with this requirement, we first examine a method explicitly designed to detect local motions in DSA. Then, we implement a motion compensation algorithm by means of block matching on modern graphics hardware. Both methods search for maximal local similarity by evaluating a histogram-based measure. In this context, we are the first who have mapped an optimizing search strategy on graphics hardware while paralleling block matching. Moreover, we provide an innovative method for creating histograms on graphics hardware with vertex texturing and frame buffer blending. It turns out that both methods can effectively correct the artifacts in most case, as the hardware implementation of block matching performs much faster: the displacements of two 1024 x 1024 images can be calculated at 3 frames/s with integer precision or 2 frames/s with sub-pixel precision. Preliminary clinical evaluation indicates that the computation with integer precision could already be sufficient.

  6. Robust baseline subtraction for ultrasonic full wavefield analysis

    NASA Astrophysics Data System (ADS)

    Alguri, K. Supreet; Michaels, Jennifer E.; Harley, Joel B.

    2017-02-01

    Full wavefield analysis is used to study and characterize the interaction between waves and structural damage. Yet, as wavefields are measured and as damage evolves in a structure, environmental and operational variations can significantly affect wave propagation. Several approaches, including time-stretching and optimal baseline selection methods, can reduce variations, but these methods are often limited to specific effects, are ineffective for large environmental variations, or require an impractical number of prior baseline measurements. This paper presents a robust methodology for subtracting wavefields and isolating wave-damage interactions. The method is based on dictionary learning. It is robust to multiple types of environmental and operational variations and requires only one initial baseline. We learn the dictionary, which describes wave propagation for a particular wavefield, based on multiple frequencies of a baseline wavefield. We then use the dictionary and sparse regression to create new baselines for measurements with different environmental and operational conditions. The new baseline is then subtracted from the new wavefield to isolate damage wavefield.

  7. Background Subtraction Based on Three-Dimensional Discrete Wavelet Transform.

    PubMed

    Han, Guang; Wang, Jinkuan; Cai, Xi

    2016-03-30

    Background subtraction without a separate training phase has become a critical task, because a sufficiently long and clean training sequence is usually unavailable, and people generally thirst for immediate detection results from the first frame of a video. Without a training phase, we propose a background subtraction method based on three-dimensional (3D) discrete wavelet transform (DWT). Static backgrounds with few variations along the time axis are characterized by intensity temporal consistency in the 3D space-time domain and, hence, correspond to low-frequency components in the 3D frequency domain. Enlightened by this, we eliminate low-frequency components that correspond to static backgrounds using the 3D DWT in order to extract moving objects. Owing to the multiscale analysis property of the 3D DWT, the elimination of low-frequency components in sub-bands of the 3D DWT is equivalent to performing a pyramidal 3D filter. This 3D filter brings advantages to our method in reserving the inner parts of detected objects and reducing the ringing around object boundaries. Moreover, we make use of wavelet shrinkage to remove disturbance of intensity temporal consistency and introduce an adaptive threshold based on the entropy of the histogram to obtain optimal detection results. Experimental results show that our method works effectively in situations lacking training opportunities and outperforms several popular techniques.

  8. Background Subtraction Based on Three-Dimensional Discrete Wavelet Transform

    PubMed Central

    Han, Guang; Wang, Jinkuan; Cai, Xi

    2016-01-01

    Background subtraction without a separate training phase has become a critical task, because a sufficiently long and clean training sequence is usually unavailable, and people generally thirst for immediate detection results from the first frame of a video. Without a training phase, we propose a background subtraction method based on three-dimensional (3D) discrete wavelet transform (DWT). Static backgrounds with few variations along the time axis are characterized by intensity temporal consistency in the 3D space-time domain and, hence, correspond to low-frequency components in the 3D frequency domain. Enlightened by this, we eliminate low-frequency components that correspond to static backgrounds using the 3D DWT in order to extract moving objects. Owing to the multiscale analysis property of the 3D DWT, the elimination of low-frequency components in sub-bands of the 3D DWT is equivalent to performing a pyramidal 3D filter. This 3D filter brings advantages to our method in reserving the inner parts of detected objects and reducing the ringing around object boundaries. Moreover, we make use of wavelet shrinkage to remove disturbance of intensity temporal consistency and introduce an adaptive threshold based on the entropy of the histogram to obtain optimal detection results. Experimental results show that our method works effectively in situations lacking training opportunities and outperforms several popular techniques. PMID:27043570

  9. Fast Image Subtraction Using Multi-cores and GPUs

    NASA Astrophysics Data System (ADS)

    Hartung, Steven; Shukla, H.

    2013-01-01

    Many important image processing techniques in astronomy require a massive number of computations per pixel. Among them is an image differencing technique known as Optimal Image Subtraction (OIS), which is very useful for detecting and characterizing transient phenomena. Like many image processing routines, OIS computations increase proportionally with the number of pixels being processed, and the number of pixels in need of processing is increasing rapidly. Utilizing many-core graphical processing unit (GPU) technology in a hybrid conjunction with multi-core CPU and computer clustering technologies, this work presents a new astronomy image processing pipeline architecture. The chosen OIS implementation focuses on the 2nd order spatially-varying kernel with the Dirac delta function basis, a powerful image differencing method that has seen limited deployment in part because of the heavy computational burden. This tool can process standard image calibration and OIS differencing in a fashion that is scalable with the increasing data volume. It employs several parallel processing technologies in a hierarchical fashion in order to best utilize each of their strengths. The Linux/Unix based application can operate on a single computer, or on an MPI configured cluster, with or without GPU hardware. With GPU hardware available, even low-cost commercial video cards, the OIS convolution and subtraction times for large images can be accelerated by up to three orders of magnitude.

  10. Nonclassicality and decoherence of photon-subtracted squeezed states

    NASA Astrophysics Data System (ADS)

    Biswas, Asoka; Agarwal, Girish S.

    2007-03-01

    Single-photon subtracted squeezed vacuum states are equivalent to Schrodinger kitten states and show non-Gaussian nature in phase space. Such states are useful in entanglement distillation, loophole-free test of Bell's inequality, and quantum computing. We discuss nonclassical properties of these states in terms of the sub-Poissonian statistics and the negativity of the Wigner function. We derive a compact expression for the Wigner function from which we find the region of phase space where Wigner function is negative. We find an upper bound on the squeezing parameter for the state to exhibit sub-Poissonian statistics. We then study the effect of decoherence on the single-photon subtracted squeezed states. We present results for two different models of decoherence, viz. amplitude decay model and the phase diffusion model. In each case we give analytical results for the time evolution of the state. We discuss the loss of nonclassicality as a result of decoherence. We show through the study of their phase-space properties how these states decay to vacuum due to the decay of photons. We show that phase damping leads to very slow decoherence than the photon-number decay and the state remains nonclassical at long times.

  11. Cadmium Subtraction Method for the Active Albedo Neutron Interrogation of Uranium

    SciTech Connect

    Worrall, Louise G.; Croft, Stephen

    2015-02-01

    This report describes work performed under the Next Generation Safeguards Initiative (NGSI) Cadmium Subtraction Project. The project objective was to explore the difference between the traditional cadmium (Cd) ratio signature and a proposed alternative Cd subtraction (or Cd difference) approach. The thinking behind the project was that a Cd subtraction method would provide a more direct measure of multiplication than the existing Cd ratio method. At the same time, it would be relatively insensitive to changes in neutron detection efficiency when properly calibrated. This is the first published experimental comparison and evaluation of the Cd ratio and Cd subtraction methods.

  12. Evaluation of interventions to reduce multiply controlled vocal stereotypy.

    PubMed

    Scalzo, Rachel; Henry, Kelsey; Davis, Tonya N; Amos, Kally; Zoch, Tamara; Turchan, Sarah; Wagner, Tara

    2015-07-01

    This study examined four interventions targeted at decreasing multiply controlled vocal stereotypy for a 12-year-old boy diagnosed with autism spectrum disorder and a severe intellectual disability. These interventions included Noncontingent Music, Differential Reinforcement of Other Behaviors, Self-Recording, and Functional Communication Training (FCT). In addition to measuring vocal stereotypy during each condition, task engagement and challenging behavior were also monitored. Across conditions, vocal stereotypy did not vary significantly from baseline except in FCT, when it decreased significantly. Task engagement was higher in this condition as well. It is hypothesized that FCT provided an enriched environment by increasing social interaction and access to desired items as well as removal of less preferred activities. For these reasons, there was a decrease in the need for the participant to engage in vocal stereotypy and challenging behavior and increase in his ability to engage in a task.

  13. Slow Interatomic Coulombic Decay of Multiply Excited Neon Clusters

    NASA Astrophysics Data System (ADS)

    Iablonskyi, D.; Nagaya, K.; Fukuzawa, H.; Motomura, K.; Kumagai, Y.; Mondal, S.; Tachibana, T.; Takanashi, T.; Nishiyama, T.; Matsunami, K.; Johnsson, P.; Piseri, P.; Sansone, G.; Dubrouil, A.; Reduzzi, M.; Carpeggiani, P.; Vozzi, C.; Devetta, M.; Negro, M.; Calegari, F.; Trabattoni, A.; Castrovilli, M. C.; Faccialà, D.; Ovcharenko, Y.; Möller, T.; Mudrich, M.; Stienkemeier, F.; Coreno, M.; Alagia, M.; Schütte, B.; Berrah, N.; Kuleff, A. I.; Jabbari, G.; Callegari, C.; Plekan, O.; Finetti, P.; Spezzani, C.; Ferrari, E.; Allaria, E.; Penco, G.; Serpico, C.; De Ninno, G.; Nikolov, I.; Diviacco, B.; Di Mitri, S.; Giannessi, L.; Prince, K. C.; Ueda, K.

    2016-12-01

    Ne clusters (˜5000 atoms ) were resonantly excited (2 p →3 s ) by intense free electron laser (FEL) radiation at FERMI. Such multiply excited clusters can decay nonradiatively via energy exchange between at least two neighboring excited atoms. Benefiting from the precise tunability and narrow bandwidth of seeded FEL radiation, specific sites of the Ne clusters were probed. We found that the relaxation of cluster surface atoms proceeds via a sequence of interatomic or intermolecular Coulombic decay (ICD) processes while ICD of bulk atoms is additionally affected by the surrounding excited medium via inelastic electron scattering. For both cases, cluster excitations relax to atomic states prior to ICD, showing that this kind of ICD is rather slow (picosecond range). Controlling the average number of excitations per cluster via the FEL intensity allows a coarse tuning of the ICD rate.

  14. Imaging With Nature: Compressive Imaging Using a Multiply Scattering Medium

    PubMed Central

    Liutkus, Antoine; Martina, David; Popoff, Sébastien; Chardon, Gilles; Katz, Ori; Lerosey, Geoffroy; Gigan, Sylvain; Daudet, Laurent; Carron, Igor

    2014-01-01

    The recent theory of compressive sensing leverages upon the structure of signals to acquire them with much fewer measurements than was previously thought necessary, and certainly well below the traditional Nyquist-Shannon sampling rate. However, most implementations developed to take advantage of this framework revolve around controlling the measurements with carefully engineered material or acquisition sequences. Instead, we use the natural randomness of wave propagation through multiply scattering media as an optimal and instantaneous compressive imaging mechanism. Waves reflected from an object are detected after propagation through a well-characterized complex medium. Each local measurement thus contains global information about the object, yielding a purely analog compressive sensing method. We experimentally demonstrate the effectiveness of the proposed approach for optical imaging by using a 300-micrometer thick layer of white paint as the compressive imaging device. Scattering media are thus promising candidates for designing efficient and compact compressive imagers. PMID:25005695

  15. Multiplying steady-state culture in multi-reactor system.

    PubMed

    Erm, Sten; Adamberg, Kaarel; Vilu, Raivo

    2014-11-01

    Cultivation of microorganisms in batch experiments is fast and economical but the conditions therein change constantly, rendering quantitative data interpretation difficult. By using chemostat with controlled environmental conditions the physiological state of microorganisms is fixed; however, the unavoidable stabilization phase makes continuous methods resource consuming. Material can be spared by using micro scale devices, which however have limited analysis and process control capabilities. Described herein are a method and a system combining the high throughput of batch with the controlled environment of continuous cultivations. Microorganisms were prepared in one bioreactor followed by culture distribution into a network of bioreactors and continuation of independent steady state experiments therein. Accelerostat cultivation with statistical analysis of growth parameters demonstrated non-compromised physiological state following distribution, thus the method effectively multiplied steady state culture of microorganisms. The theoretical efficiency of the system was evaluated in inhibitory compound analysis using repeated chemostat to chemostat transfers.

  16. Multigroup diffusion preconditioners for multiplying fixed-source transport problems

    NASA Astrophysics Data System (ADS)

    Roberts, Jeremy A.; Forget, Benoit

    2014-10-01

    Several preconditioners based on multigroup diffusion are developed for application to multiplying fixed-source transport problems using the discrete ordinates method. By starting from standard, one-group, diffusion synthetic acceleration (DSA), a multigroup diffusion preconditioner is constructed that shares the same fine mesh as the transport problem. As a cheaper but effective alternative, a two-grid, coarse-mesh, multigroup diffusion preconditioner is examined, for which a variety of homogenization schemes are studied to generate the coarse mesh operator. Finally, a transport-corrected diffusion preconditioner based on application of the Newton-Shulz algorithm is developed. The results of several numerical studies indicate the coarse-mesh, diffusion preconditioners work very well. In particular, a coarse-mesh, transport-corrected, diffusion preconditioner reduced the computational time of multigroup GMRES by up to a factor of 17 and outperformed best-case Gauss-Seidel results by over an order of magnitude for all problems studied.

  17. A Gas Electron Multiplier (GEM) Detector for Fast Neutron Imaging

    NASA Astrophysics Data System (ADS)

    Jewett, C. C.; McMahan, M.; Cerny, J.; Heilbronn, L.; Johnson, M.

    2008-10-01

    We have built a Gas Electron Multiplier (GEM) detector for detection of fast neutrons at Lawrence Berkeley National Laboratory. The detector consists of a 0.0625 inch thick polypropylene neutron converter, three GEM foils and a grid of 16 readout pads on a printed circuit board. In this talk, we present images of the GEM detector, the results of tests with ^60Co, AmBe sources and our neutron beam, and a comparison between the proposed fast neutron GEM detector and a fast neutron ^238U fission chamber we purchased. One of the advantages of the GEM detector over the fission chamber is the fact that it provides the x-y position information of the neutrons.

  18. Multiply-warped product metrics and reduction of Einstein equations

    NASA Astrophysics Data System (ADS)

    Gholami, Fateme; Darabi, Farhad; Haji-Badali, Ali

    It is shown that for every multidimensional metric in the multiply-warped product form M¯ = K ×f1M1 ×f2M2 with warp functions f1, f2, associated to the submanifolds M1, M2 of dimensions n1, n2 respectively, one can find the corresponding Einstein equations ḠAB = -Λ¯ḡAB, with cosmological constant Λ¯, which are reducible to the Einstein equations Gαβ = -Λ1gαβ and Gij = -Λ2hij on the submanifolds M1, M2, with cosmological constants Λ1 and Λ2, respectively, where Λ¯, Λ1 and Λ2 are functions of f1, f2 and n1, n2.

  19. Characterization of Silicon PhotoMultipliers at LNS-INFN

    SciTech Connect

    Cosentino, L.; Finocchiaro, P.; Pappalardo, A.

    2011-12-13

    The Silicon PhotoMultipliers (SiPMs) are a new generation of photodetectors having high sensitivity, excellent time resolution, compactness, low power supply, and insensitivity to magnetic fields. Their properties make them a valid alternative to the PMTs in several fields, such as particle physics, medicine, and space technology. At Laboratori Nazionali del Sud (LNS), a complete characterization of samples developed by different companies (Hamamatsu, STM, SensL) has been performed in order to measure the most significant properties, consisting of the dark noise, cross talk probability, photon detection efficiency, and charge and timing resolutions. Measurements have also been performed coupling the SiPMs with scintillating fibres and small size LYSO scintillators in order to investigate possible applications in Positron Emission Tomography (PET) diagnostics and in the monitoring of nuclear waste sites.

  20. Development of a thick gas electron multiplier for microdosimetry

    NASA Astrophysics Data System (ADS)

    Orchard, G. M.; Chin, K.; Prestwich, W. V.; Waker, A. J.; Byun, S. H.

    2011-05-01

    A new tissue-equivalent proportional counter based on a thick gas electron multiplier (THGEM) was developed and tested for microdosimetry. A systematic test was conducted at the McMaster Accelerator Laboratory to investigate the overall performance of the prototype detector. A mixed neutron-gamma-ray radiation field was generated using the 7Li(p,n) reaction. The detector was operated at low voltage initially to test the stability and then the relative multiplication gain was measured as a function of the operating high voltage. A drift potential of 100 V and a THGEM bias of 727 V generated a multiplication gain sufficient for the detection of both neutron and gamma-ray radiation. A consistent microdosimetric pattern was observed between the THGEM detector and standard TEPC for microdosimetry.

  1. Characterization of Silicon PhotoMultipliers at LNS-INFN

    NASA Astrophysics Data System (ADS)

    Cosentino, L.; Finocchiaro, P.; Pappalardo, A.

    2011-12-01

    The Silicon PhotoMultipliers (SiPMs) are a new generation of photodetectors having high sensitivity, excellent time resolution, compactness, low power supply, and insensitivity to magnetic fields. Their properties make them a valid alternative to the PMTs in several fields, such as particle physics, medicine, and space technology. At Laboratori Nazionali del Sud (LNS), a complete characterization of samples developed by different companies (Hamamatsu, STM, SensL) has been performed in order to measure the most significant properties, consisting of the dark noise, cross talk probability, photon detection efficiency, and charge and timing resolutions. Measurements have also been performed coupling the SiPMs with scintillating fibres and small size LYSO scintillators in order to investigate possible applications in Positron Emission Tomography (PET) diagnostics and in the monitoring of nuclear waste sites.

  2. Add Control: plant virtualization for control solutions in WWTP.

    PubMed

    Maiza, M; Bengoechea, A; Grau, P; De Keyser, W; Nopens, I; Brockmann, D; Steyer, J P; Claeys, F; Urchegui, G; Fernández, O; Ayesa, E

    2013-01-01

    This paper summarizes part of the research work carried out in the Add Control project, which proposes an extension of the wastewater treatment plant (WWTP) models and modelling architectures used in traditional WWTP simulation tools, addressing, in addition to the classical mass transformations (transport, physico-chemical phenomena, biological reactions), all the instrumentation, actuation and automation & control components (sensors, actuators, controllers), considering their real behaviour (signal delays, noise, failures and power consumption of actuators). Its ultimate objective is to allow a rapid transition from the simulation of the control strategy to its implementation at full-scale plants. Thus, this paper presents the application of the Add Control simulation platform for the design and implementation of new control strategies at the WWTP of Mekolalde.

  3. Planar varactor frequency multiplier devices with blocking barrier

    NASA Technical Reports Server (NTRS)

    Lieneweg, Udo (Inventor); Frerking, Margaret A. (Inventor); Maserjian, Joseph (Inventor)

    1994-01-01

    The invention relates to planar varactor frequency multiplier devices with a heterojunction blocking barrier for near millimeter wave radiation of moderate power from a fundamental input wave. The space charge limitation of the submillimeter frequency multiplier devices of the BIN(sup +) type is overcome by a diode structure comprising an n(sup +) doped layer of semiconductor material functioning as a low resistance back contact, a layer of semiconductor material with n-type doping functioning as a drift region grown on the back contact layer, a delta doping sheet forming a positive charge at the interface of the drift region layer with a barrier layer, and a surface metal contact. The layers thus formed on an n(sup +) doped layer may be divided into two isolated back-to-back BNN(sup +) diodes by separately depositing two surface metal contacts. By repeating the sequence of the drift region layer and the barrier layer with the delta doping sheet at the interfaces between the drift and barrier layers, a plurality of stacked diodes is formed. The novelty of the invention resides in providing n-type semiconductor material for the drift region in a GaAs/AlGaAs structure, and in stacking a plurality of such BNN(sup +) diodes stacked for greater output power with and connected back-to-back with the n(sup +) GaAs layer as an internal back contact and separate metal contact over an AlGaAs barrier layer on top of each stack.

  4. Randomized Controlled Trials of Add-On Antidepressants in Schizophrenia

    PubMed Central

    Joffe, Grigori; Stenberg, Jan-Henry

    2015-01-01

    Background: Despite adequate treatment with antipsychotics, a substantial number of patients with schizophrenia demonstrate only suboptimal clinical outcome. To overcome this challenge, various psychopharmacological combination strategies have been used, including antidepressants added to antipsychotics. Methods: To analyze the efficacy of add-on antidepressants for the treatment of negative, positive, cognitive, depressive, and antipsychotic-induced extrapyramidal symptoms in schizophrenia, published randomized controlled trials assessing the efficacy of adjunctive antidepressants in schizophrenia were reviewed using the following parameters: baseline clinical characteristics and number of patients, their on-going antipsychotic treatment, dosage of the add-on antidepressants, duration of the trial, efficacy measures, and outcomes. Results: There were 36 randomized controlled trials reported in 41 journal publications (n=1582). The antidepressants used were the selective serotonin reuptake inhibitors, duloxetine, imipramine, mianserin, mirtazapine, nefazodone, reboxetin, trazodone, and bupropion. Mirtazapine and mianserin showed somewhat consistent efficacy for negative symptoms and both seemed to enhance neurocognition. Trazodone and nefazodone appeared to improve the antipsychotics-induced extrapyramidal symptoms. Imipramine and duloxetine tended to improve depressive symptoms. No clear evidence supporting selective serotonin reuptake inhibitors’ efficacy on any clinical domain of schizophrenia was found. Add-on antidepressants did not worsen psychosis. Conclusions: Despite a substantial number of randomized controlled trials, the overall efficacy of add-on antidepressants in schizophrenia remains uncertain mainly due to methodological issues. Some differences in efficacy on several schizophrenia domains seem, however, to exist and to vary by the antidepressant subgroups—plausibly due to differences in the mechanisms of action. Antidepressants may not worsen

  5. Family nurse practitioners: "value add" in outpatient chronic disease management.

    PubMed

    Stephens, Lynn

    2012-12-01

    Nurse practitioners are capable leaders in primary care design as practices nationwide move to consider and adopt the patient-centered medical home. The chronic care model provides a structure to enhance the care of chronic illness. Nurse practitioners are instrumental in many areas of this model as both leaders and caregivers. Safety and quality are basic medical home goals; nurse practitioners enhance both. The addition of a nurse practitioner to a practice is an effective "value add" in every way.

  6. Stereovision Imaging in Smart Mobile Phone Using Add on Prisms

    NASA Astrophysics Data System (ADS)

    Bar-Magen Numhauser, Jonathan; Zalevsky, Zeev

    2014-03-01

    In this work we present the use of a prism-based add on component installed on top of a smart phone to achieve stereovision capabilities using iPhone mobile operating system. Through these components and the combination of the appropriate application programming interface and mathematical algorithms the obtained results will permit the analysis of possible enhancements for new uses to such system, in a variety of areas including medicine and communications.

  7. Higher Curvature Effects in the ADD and RS Models

    SciTech Connect

    Rizzo, Thomas G.; /SLAC

    2006-07-05

    Over the last few years several extra-dimensional models have been introduced in attempt to deal with the hierarchy problem. These models can lead to rather unique and spectacular signatures at Terascale colliders such as the LHC and ILC. The ADD and RS models, though quite distinct, have many common feature including a constant curvature bulk, localized Standard Model(SM) fields and the assumption of the validity of the EH action as a description of gravitational interactions.

  8. Add-on unidirectional elastic metamaterial plate cloak

    PubMed Central

    Lee, Min Kyung; Kim, Yoon Young

    2016-01-01

    Metamaterial cloaks control the propagation of waves to make an object invisible or insensible. To manipulate elastic waves in space, a metamaterial cloak is typically embedded in a base system that includes or surrounds a target object. The embedding is undesirable because it structurally weakens or permanently alters the base system. In this study, we propose a new add-on metamaterial elastic cloak that can be placed over and mechanically coupled with a base structure without embedding. We designed an add-on type annular metamaterial plate cloak through conformal mapping, fabricated it and performed cloaking experiments in a thin-plate with a hole. Experiments were performed in a thin plate by using the lowest symmetric Lamb wave centered at 100 kHz. As a means to check the cloaking performance of the add-on elastic plate cloak, possibly as a temporary stress reliever or a so-called “stress bandage”, the degree of stress concentration mitigation and the recovery from the perturbed wave field due to a hole were investigated. PMID:26860896

  9. Optical add/drop filter for wavelength division multiplexed systems

    DOEpatents

    Deri, Robert J.; Strand, Oliver T.; Garrett, Henry E.

    2002-01-01

    An optical add/drop filter for wavelength division multiplexed systems and construction methods are disclosed. The add/drop filter includes a first ferrule having a first pre-formed opening for receiving a first optical fiber; an interference filter oriented to pass a first set of wavelengths along the first optical fiber and reflect a second set of wavelengths; and, a second ferrule having a second pre-formed opening for receiving the second optical fiber, and the reflected second set of wavelengths. A method for constructing the optical add/drop filter consists of the steps of forming a first set of openings in a first ferrule; inserting a first set of optical fibers into the first set of openings; forming a first set of guide pin openings in the first ferrule; dividing the first ferrule into a first ferrule portion and a second ferrule portion; forming an interference filter on the first ferrule portion; inserting guide pins through the first set of guide pin openings in the first ferrule portion and second ferrule portion to passively align the first set of optical fibers; removing material such that light reflected from the interference filter from the first set of optical fibers is accessible; forming a second set of openings in a second ferrule; inserting a second set of optical fibers into the second set of openings; and positioning the second ferrule with respect to the first ferrule such that the second set of optical fibers receive the light reflected from the interference filter.

  10. Add-on unidirectional elastic metamaterial plate cloak.

    PubMed

    Lee, Min Kyung; Kim, Yoon Young

    2016-02-10

    Metamaterial cloaks control the propagation of waves to make an object invisible or insensible. To manipulate elastic waves in space, a metamaterial cloak is typically embedded in a base system that includes or surrounds a target object. The embedding is undesirable because it structurally weakens or permanently alters the base system. In this study, we propose a new add-on metamaterial elastic cloak that can be placed over and mechanically coupled with a base structure without embedding. We designed an add-on type annular metamaterial plate cloak through conformal mapping, fabricated it and performed cloaking experiments in a thin-plate with a hole. Experiments were performed in a thin plate by using the lowest symmetric Lamb wave centered at 100 kHz. As a means to check the cloaking performance of the add-on elastic plate cloak, possibly as a temporary stress reliever or a so-called "stress bandage", the degree of stress concentration mitigation and the recovery from the perturbed wave field due to a hole were investigated.

  11. 40 CFR 75.34 - Units with add-on emission controls.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Units with add-on emission controls... add-on emission controls. (a) The owner or operator of an affected unit equipped with add-on SO2 and... which the add-on emission controls are documented to be operating properly, as described in the...

  12. 24 CFR 990.190 - Other formula expenses (add-ons).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false Other formula expenses (add-ons... formula expenses (add-ons). In addition to calculating operating subsidy based on the PEL and UEL, a PHA's eligible formula expenses shall be increased by add-ons. The allowed add-ons are: (a) Self-sufficiency....

  13. 40 CFR 75.34 - Units with add-on emission controls.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Units with add-on emission controls... add-on emission controls. (a) The owner or operator of an affected unit equipped with add-on SO2 and... which the add-on emission controls are documented to be operating properly, as described in the...

  14. 40 CFR 75.34 - Units with add-on emission controls.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 17 2012-07-01 2012-07-01 false Units with add-on emission controls... add-on emission controls. (a) The owner or operator of an affected unit equipped with add-on SO2 and... which the add-on emission controls are documented to be operating properly, as described in the...

  15. 24 CFR 990.190 - Other formula expenses (add-ons).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 4 2012-04-01 2012-04-01 false Other formula expenses (add-ons... formula expenses (add-ons). In addition to calculating operating subsidy based on the PEL and UEL, a PHA's eligible formula expenses shall be increased by add-ons. The allowed add-ons are: (a) Self-sufficiency....

  16. 40 CFR 75.34 - Units with add-on emission controls.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Units with add-on emission controls... add-on emission controls. (a) The owner or operator of an affected unit equipped with add-on SO2 and... which the add-on emission controls are documented to be operating properly, as described in the...

  17. 24 CFR 990.190 - Other formula expenses (add-ons).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 4 2014-04-01 2014-04-01 false Other formula expenses (add-ons... formula expenses (add-ons). In addition to calculating operating subsidy based on the PEL and UEL, a PHA's eligible formula expenses shall be increased by add-ons. The allowed add-ons are: (a) Self-sufficiency....

  18. 24 CFR 990.190 - Other formula expenses (add-ons).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Other formula expenses (add-ons... formula expenses (add-ons). In addition to calculating operating subsidy based on the PEL and UEL, a PHA's eligible formula expenses shall be increased by add-ons. The allowed add-ons are: (a) Self-sufficiency....

  19. 40 CFR 75.34 - Units with add-on emission controls.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Units with add-on emission controls... add-on emission controls. (a) The owner or operator of an affected unit equipped with add-on SO2 and... which the add-on emission controls are documented to be operating properly, as described in the...

  20. Multinuclide digital subtraction imaging in symptomatic prostnetic joints

    SciTech Connect

    Chafetz, N.; Hattner, R.S.; Ruarke, W.C.; Helms, C.A.; Genant, H.K.; Murray, W.R.

    1985-06-01

    One hundred eleven patients with symptomatic prosthetic joints (86 hips, 23 knees, and two shoulders) were evaluated for prosthetic loosening and infection by combined technetium-99m-MDP/gallium-67 digital subtraction imaging. Clinical correlation was based on the assessment of loosening and bacterial cultures obtained at the time of surgery in 54 patients, joint aspiration cultures obtained in 37 patients, and long-term clinical follow-up for greater than 1.5 years in an additional 15 patients. Results revealed an 80-90% predictive value of a positive test for loosening, and a 95% predictive value of a negative test for infection. However, because of the low sensitivities and specificities observed, this approach to the evaluation of symptomatic prosthetic joints does not seem cost effective.

  1. Intermediate Palomar Transient Factory: Realtime Image Subtraction Pipeline

    NASA Astrophysics Data System (ADS)

    Cao, Yi; Nugent, Peter E.; Kasliwal, Mansi M.

    2016-11-01

    A fast-turnaround pipeline for realtime data reduction plays an essential role in discovering and permitting follow-up observations to young supernovae and fast-evolving transients in modern time-domain surveys. In this paper, we present the realtime image subtraction pipeline in the intermediate Palomar Transient Factory. By using high-performance computing, efficient databases, and machine-learning algorithms, this pipeline manages to reliably deliver transient candidates within 10 minutes of images being taken. Our experience in using high-performance computing resources to process big data in astronomy serves as a trailblazer to dealing with data from large-scale time-domain facilities in the near future.

  2. Ambient-Light-Canceling Camera Using Subtraction of Frames

    NASA Technical Reports Server (NTRS)

    Morookian, John Michael

    2004-01-01

    The ambient-light-canceling camera (ALCC) is a proposed near-infrared electronic camera that would utilize a combination of (1) synchronized illumination during alternate frame periods and (2) subtraction of readouts from consecutive frames to obtain images without a background component of ambient light. The ALCC is intended especially for use in tracking the motion of an eye by the pupil center corneal reflection (PCCR) method. Eye tracking by the PCCR method has shown potential for application in human-computer interaction for people with and without disabilities, and for noninvasive monitoring, detection, and even diagnosis of physiological and neurological deficiencies. In the PCCR method, an eye is illuminated by near-infrared light from a lightemitting diode (LED). Some of the infrared light is reflected from the surface of the cornea. Some of the infrared light enters the eye through the pupil and is reflected from back of the eye out through the pupil a phenomenon commonly observed as the red-eye effect in flash photography. An electronic camera is oriented to image the user's eye. The output of the camera is digitized and processed by algorithms that locate the two reflections. Then from the locations of the centers of the two reflections, the direction of gaze is computed. As described thus far, the PCCR method is susceptible to errors caused by reflections of ambient light. Although a near-infrared band-pass optical filter can be used to discriminate against ambient light, some sources of ambient light have enough in-band power to compete with the LED signal. The mode of operation of the ALCC would complement or supplant spectral filtering by providing more nearly complete cancellation of the effect of ambient light. In the operation of the ALCC, a near-infrared LED would be pulsed on during one camera frame period and off during the next frame period. Thus, the scene would be illuminated by both the LED (signal) light and the ambient (background) light

  3. Suppression Subtractive Hybridization (SSH) and its modifications in microbiological research.

    PubMed

    Huang, Xiaowei; Li, Yunxia; Niu, Qiuhong; Zhang, Keqin

    2007-09-01

    Suppression subtractive hybridization (SSH) is an effective approach to identify the genes that vary in expression levels during different biological processes. It is often used in higher eukaryotes to study the molecular regulation in complex pathogenic progress, such as tumorigenesis and other chronic multigene-associated diseases. Because microbes have relatively smaller genomes compared with eukaryotes, aside from the analysis at the mRNA level, SSH as well as its modifications have been further employed to isolate specific chromosomal locus, study genomic diversity related with exceptional bacterial secondary metabolisms or genes with special microbial function. This review introduces the SSH and its associated methods and focus on their applications to detect specific functional genes or DNA markers in microorganisms.

  4. Digital subtraction angiography for preoperative evaluation of extremity tumors

    SciTech Connect

    Paushter, D.M.; Borkowski, G.R.; Buonocore, E.; Belhobek, G.H.; Marks, K.E.

    1983-07-01

    A retrospective study was undertaken to evaluate the role of digital subtraction angiography (DSA) in the surgical planning of musculoskeletal neoplasms. Thirteen patients with primary bone and soft-tissue tumors were examined by CT and DSA. Three patients also had conventional angiography. DSA yielded surgically useful information in 10 patients, comparable to that expected from conventional angiography. DSA was most helpful in demonstrating the presence or absence of major vessel involvement by tumor when this could not be ascertained definitely on CT. Demonstration of mass extent by CT was accurate in 11 patients. Results of this study suggest that the combination of CT and DSA is useful in the preoperative evaluation of selected extremity tumors and should diminish the need for conventional angiography.

  5. Real-time image subtraction using phase reversal technique

    NASA Astrophysics Data System (ADS)

    Venkateswara Rao, Vuyyuru; Krishna Mohan, Nandigana K.

    1999-10-01

    A simple coherent interferometric processing method for image subtraction in real-time is presented. The proposed method is based on interferometric principle using Mach- Zehnder interferometer. The phase reversal is accomplished by varying the pressure within an air-filled quartz cell inserted in one of the arms of the interferometer. Initially, the interferometer is aligned to obtain broad interference fringes in the cell region. Then the input imageries are introduced in both the arms of the interferometer and adjusted for exact registration as seen in the plane of observation. By introducing a phase change of (pi) -rad between the two arms of the interferometer, the difference between the inputs is detected in real-time on the monitor. Phase shift calibration and information processing of the proposed method is presented with the results.

  6. Background Subtraction Based on Color and Depth Using Active Sensors

    PubMed Central

    Fernandez-Sanchez, Enrique J.; Diaz, Javier; Ros, Eduardo

    2013-01-01

    Depth information has been used in computer vision for a wide variety of tasks. Since active range sensors are currently available at low cost, high-quality depth maps can be used as relevant input for many applications. Background subtraction and video segmentation algorithms can be improved by fusing depth and color inputs, which are complementary and allow one to solve many classic color segmentation issues. In this paper, we describe one fusion method to combine color and depth based on an advanced color-based algorithm. This technique has been evaluated by means of a complete dataset recorded with Microsoft Kinect, which enables comparison with the original method. The proposed method outperforms the others in almost every test, showing more robustness to illumination changes, shadows, reflections and camouflage. PMID:23857259

  7. An Improved Spectral Background Subtraction Method Based on Wavelet Energy.

    PubMed

    Zhao, Fengkui; Wang, Jian; Wang, Aimin

    2016-12-01

    Most spectral background subtraction methods rely on the difference in frequency response of background compared with characteristic peaks. It is difficult to extract accurately the background components from the spectrum when characteristic peaks and background have overlaps in frequency domain. An improved background estimation algorithm based on iterative wavelet transform (IWT) is presented. The wavelet entropy principle is used to select the best wavelet basis. A criterion based on wavelet energy theory to determine the optimal iteration times is proposed. The case of energy dispersive X-ray spectroscopy is discussed for illustration. A simulated spectrum with a prior known background and an experimental spectrum are tested. The processing results of the simulated spectrum is compared with non-IWT and it demonstrates the superiority of the IWT. It has great significance to improve the accuracy for spectral analysis.

  8. Plasma tomographic reconstruction from tangentially viewing camera with background subtraction

    SciTech Connect

    Odstrčil, M.; Mlynář, J.; Weinzettl, V.; Háček, P.; Verdoolaege, G.; Berta, M.

    2014-01-15

    Light reflections are one of the main and often underestimated issues of plasma emissivity reconstruction in visible light spectral range. Metallic and other specular components of tokamak generate systematic errors in the optical measurements that could lead to wrong interpretation of data. Our analysis is performed at data from the tokamak COMPASS. It is a D-shaped tokamak with specular metallic vessel and possibility of the H-mode plasma. Data from fast visible light camera were used for tomographic reconstruction with background reflections subtraction to study plasma boundary. In this article, we show that despite highly specular tokamak wall, it is possible to obtain a realistic reconstruction. The developed algorithm shows robust results despite of systematic errors in the optical measurements and calibration. The motivation is to obtain an independent estimate of the plasma boundary shape.

  9. Model Evaluation and Multiple Strategies in Cognitive Diagnosis: An Analysis of Fraction Subtraction Data

    ERIC Educational Resources Information Center

    de la Torre, Jimmy; Douglas, Jeffrey A.

    2008-01-01

    This paper studies three models for cognitive diagnosis, each illustrated with an application to fraction subtraction data. The objective of each of these models is to classify examinees according to their mastery of skills assumed to be required for fraction subtraction. We consider the DINA model, the NIDA model, and a new model that extends the…

  10. Efficiency and Flexibility of Indirect Addition in the Domain of Multi-Digit Subtraction

    ERIC Educational Resources Information Center

    Torbeyns, Joke; Ghesquiere, Pol; Verschaffel, Lieven

    2009-01-01

    This article discusses the characteristics of the indirect addition strategy (IA) in the domain of multi-digit subtraction. In two studies, adults' use of IA on three-digit subtractions with a small, medium, or large difference between the integers was analysed using the choice/no-choice method. Results from both studies indicate that adults…

  11. Putting Essential Understanding of Addition and Subtraction into Practice: Pre-K-2

    ERIC Educational Resources Information Center

    Caldwell, Janet H.; Kobett, Beth; Karp, Karen

    2014-01-01

    Do your students have the incorrect idea that addition "makes numbers bigger" and subtraction "makes numbers smaller"? Do they believe that subtraction is always "taking away"? What tasks can you offer--what questions can you ask--to determine what your students know or don't know--and move them forward in their…

  12. Mental Computation or Standard Algorithm? Children's Strategy Choices on Multi-Digit Subtractions

    ERIC Educational Resources Information Center

    Torbeyns, Joke; Verschaffel, Lieven

    2016-01-01

    This study analyzed children's use of mental computation strategies and the standard algorithm on multi-digit subtractions. Fifty-eight Flemish 4th graders of varying mathematical achievement level were individually offered subtractions that either stimulated the use of mental computation strategies or the standard algorithm in one choice and two…

  13. Toddler Subtraction with Large Sets: Further Evidence for an Analog-Magnitude Representation of Number

    ERIC Educational Resources Information Center

    Slaughter, Virginia; Kamppi, Dorian; Paynter, Jessica

    2006-01-01

    Two experiments were conducted to test the hypothesis that toddlers have access to an analog-magnitude number representation that supports numerical reasoning about relatively large numbers. Three-year-olds were presented with subtraction problems in which initial set size and proportions subtracted were systematically varied. Two sets of cookies…

  14. How Do Manipulatives Help Students Communicate Their Understanding of Double-Digit Subtraction?

    ERIC Educational Resources Information Center

    Abi-Hanna, Rabab

    2016-01-01

    Multi-digit subtraction is difficult for students to learn. The purpose of this study is to explore how second-grade students communicate their understanding of double-digit subtraction through the use of manipulatives/tools. This qualitative study reports on six case studies of second-grade students where clinical interviews were the main source…

  15. On-Chip Power-Combining for High-Power Schottky Diode Based Frequency Multipliers

    NASA Technical Reports Server (NTRS)

    Siles Perez, Jose Vicente (Inventor); Chattopadhyay, Goutam (Inventor); Lee, Choonsup (Inventor); Schlecht, Erich T. (Inventor); Jung-Kubiak, Cecile D. (Inventor); Mehdi, Imran (Inventor)

    2015-01-01

    A novel MMIC on-chip power-combined frequency multiplier device and a method of fabricating the same, comprising two or more multiplying structures integrated on a single chip, wherein each of the integrated multiplying structures are electrically identical and each of the multiplying structures include one input antenna (E-probe) for receiving an input signal in the millimeter-wave, submillimeter-wave or terahertz frequency range inputted on the chip, a stripline based input matching network electrically connecting the input antennas to two or more Schottky diodes in a balanced configuration, two or more Schottky diodes that are used as nonlinear semiconductor devices to generate harmonics out of the input signal and produce the multiplied output signal, stripline based output matching networks for transmitting the output signal from the Schottky diodes to an output antenna, and an output antenna (E-probe) for transmitting the output signal off the chip into the output waveguide transmission line.

  16. Add/Compare/Select Circuit For Rapid Decoding

    NASA Technical Reports Server (NTRS)

    Budinger, James M.; Becker, Neal D.; Johnson, Peter N.

    1993-01-01

    Prototype decoding system operates at 200 Mb/s. ACS (add/compare/select) gate array is highly integrated emitter-coupled-logic circuit implementing arithmetic operations essential to Viterbi decoding of convolutionally encoded data signals. Principal advantage of circuit is speed. Operates as single unit performing eight additions and finds minimum of eight sums, or operates as two independent units, each performing four additions and finding minimum of four sums. Flexibility enables application to variety of different codes. Includes built-in self-testing circuitry, enabling unit to be tested at full speed with help of only simple test fixture.

  17. Astronomical imaging by filtered weighted-shift-and-add technique

    NASA Technical Reports Server (NTRS)

    Ribak, Erez

    1986-01-01

    The weighted-shift-and-add speckle imaging technique is analyzed using simple assumptions. The end product is shown to be a convolution of the object with a typical point-spread function (psf) that is similar in shape to the telescope psf and depends marginally on the speckle psf. A filter can be applied to each data frame before locating the maxima, either to identify the speckle locations (matched filter) or to estimate the instantaneous atmospheric psf (Wiener filter). Preliminary results show the power of the technique when applied to photon-limited data and to extended objects.

  18. Image restoration by the shift-and-add algorithm.

    PubMed

    Bagnuolo, W G

    1985-05-01

    A new method for image restoration based on the shift-and-add (SAA) algorithm is presented, the main advantages of which appear to be speed and simplicity. The SAA pattern produced by an object is given by the object correlated by a nonlinear replica of itself whose intensity distribution is strongly weighted toward the brighter pixels. A method of successive substitutions analogous to Fienup's algorithm can then be used to decorrelate the SAA pattern and recover the object. The method is applied to the case of the extended chromosphere of Betelgeuse.

  19. Multiply-ionized Atoms at Low Energy for Precise Measurements

    NASA Astrophysics Data System (ADS)

    Fogwell Hoogerheide, Shannon; Tan, Joseph N.

    2014-05-01

    Recent work at NIST introduced a new system for the slowing, capture and manipulation of multiply-ionized atoms in a controlled environment suitable for precision measurements. As a demonstration of its potentials, we have measured the lifetimes of metastable states in krypton and argon (gases), and are now extending this technique to metals such as iron. Work is also underway on a table-top apparatus that incorporates a miniature electron-beam ion trap (EBIT) coupled to a cryo-cooled, compact Penning trap to enable spectroscopic studies of interest for atomic physics, astrophysics, and metrology. This apparatus will allow charge exchange between laser-excited Rydberg rubidium atoms and isolated bare nuclei, opening the way for precision spectroscopy of one-electron ions in Rydberg states using optical frequency comb technology. Earlier theoretical work at NIST has shown that such measurements would provide a new determination of the Rydberg constant that was independent of the proton radius. Such a measurement could help resolve the proton-radius puzzle. Additional applications could include the study of very-long-lived atomic states proposed for new atomic frequency standards or laboratory studies of potential time variation of the fine structure constant. SFH acknowledges funding through a National Research Council Reseach Associateship award.

  20. Development of Resistive Electrode Gas Electron Multiplier (RE-GEM)

    NASA Technical Reports Server (NTRS)

    Yoshikawa, A.; Tamagawa, T.; Iwahashi, T.; Asami, F.; Takeuchi, Y.; Hayato, A.; Hamagaki, H.; Gunji, T.; Akimoto, R.; Nukariya, A.; Hayashi, S.; Ueno, K.; Ochi, A.; Oliveria, R.

    2012-01-01

    We successfully produced Resistive-Electrode Gas Electron Multiplier (RE-GEM) which has resistive electrodes instead of the metal ones which are employed for the standard GEM foils. RE-GEM has a resistive electrode of 25 micron-thick and an insulator layer of 100 micron-thick. The hole structure of RE-GEM is a single conical with the wider and narrower hole diameters of 80 micron and 60 micron, respectively. A hole pitch of RE-GEM is 140 micron. We obtained the maximum gain of about 600 and the typical energy resolution of about 20% (FWHM) at an applied voltage between the resistive electrodes of 620 V, using a collimated 8 keV X-rays from a generator in a gas mixture of 70% Ar and 30% CO2 by volume at the atmospheric pressure. We measured the effective gain as a function of the electric field of the drift region and obtained the maximum gain at an drift field of 0.5 kV/cm.

  1. Alternating Direction Method of Multiplier for Tomography With Nonlocal Regularizers

    PubMed Central

    Dewaraja, Yuni K.; Fessler, Jeffrey A.

    2015-01-01

    The ordered subset expectation maximization (OSEM) algorithm approximates the gradient of a likelihood function using a subset of projections instead of using all projections so that fast image reconstruction is possible for emission and transmission tomography such as SPECT, PET, and CT. However, OSEM does not significantly accelerate reconstruction with computationally expensive regularizers such as patch-based nonlocal (NL) regularizers, because the regularizer gradient is evaluated for every subset. We propose to use variable splitting to separate the likelihood term and the regularizer term for penalized emission tomographic image reconstruction problem and to optimize it using the alternating direction method of multiplier (ADMM). We also propose a fast algorithm to optimize the ADMM parameter based on convergence rate analysis. This new scheme enables more sub-iterations related to the likelihood term. We evaluated our ADMM for 3-D SPECT image reconstruction with a patch-based NL regularizer that uses the Fair potential function. Our proposed ADMM improved the speed of convergence substantially compared to other existing methods such as gradient descent, EM, and OSEM using De Pierro’s approach, and the limited-memory Broyden–Fletcher–Goldfarb–Shanno algorithm. PMID:25291351

  2. Fabrication of an electron multiplier utilizing diamond films

    NASA Technical Reports Server (NTRS)

    Mearini, G. T.; Krainsky, I. L.; Wang, Y. X.; Dayton, JR., J. a.; Ramesham, R.; Rose, M. F.

    1994-01-01

    High secondary electron yields (sigma=14-27) from polycrystalline diamond films on Mo substrates have been reported previously. We observed that continuous exposure to an electron beam degraded the secondary yield in vacuum as a function of fluence owing to a loss of surface hydrogen. However, the hydrogen partial pressure could be adjusted such that the high secondary yield remained stable during beam exposure. We have constructed a prototype electron multiplier using these diamond films for use in ultrahigh vacuum. A gain of 0.9 times 10(exp 5) has been measured in a d.c. mode. Palladium, titanium and aluminum nitride have been studied for possible dynode substrate materials which might eliminate the need for hydrogen during operation. Total secondary yields as high as 50 were measured from diamond on palladium and sigma was stable at 25 during heating at 700 K in vacuum. Raman spectroscopy and scanning electron microscopy showed that variations in sigma from diamond films on Pd were due to differing concentrations of non-diamond carbon.

  3. THz frequency multiplier chains base on planar Schottky diodes

    NASA Technical Reports Server (NTRS)

    Maiwald, F.; Schlecht, E.; Maestrini, A.; Chattopadhyay, G.; Pearson, J.; Pukala, D.; Mehdi, I.

    2002-01-01

    The Herschel Space Observatory (HSO), an ESA cornerstone mission with NASA contribution, will enable a comprehensive study of the galactic as well as the extra galactic universe. At the heart of this exploration are ultra sensitive coherent detectors that can allow for high-resolution spectroscopy. Successful operation of these receivers is predicated on providing a sufficiently powerful local oscillator (LO) source. Historically, a versatile space qualified LO source for frequencies beyond 500 GHz has been difficult if not impossible. This paper will focus on the effort under way to develop, build, characterize and qualify a LO chain to 1200 GHz (Band 5 on HSO) that is based on planar GaAs diodes mounted in waveguide circuits. State-of-the-art performance has been obtained from a three-stage ( x2 x 2 x 3 ) multiplier chain that can provide a peak output power of 120 uW (1178 GHz) at room temperature and a peak output power of 190 uW at 1183 GHz when cooled to 113 K. Implementation of this LO source for the Heterodyne Instrument for Far Infrared (HIFI) on HSO will be discussed in detail.

  4. Suborbital Soft X-Ray Spectroscopy with Gaseous Electron Multipliers

    NASA Astrophysics Data System (ADS)

    Rogers, Thomas D.

    This thesis consists of the design, fabrication, and launch of a sounding rocket payload to observe the spectrum of the soft X-ray emission (0.1-1 keV) from the Cygnus Loop supernova remnant. This instrument, designated the Off-plane Grating Rocket for Extended Source Spectroscopy (OGRESS), was launched from White Sands Missile Range on May 2nd, 2015. The X-ray spectrograph incorporated a wire-grid focuser feeding an array of gratings in the extreme off-plane mount which dispersed the spectrum onto Gaseous Electron Multiplier (GEM) detectors. The gain characteristics of OGRESS's GEM detectors were fully characterized with respect to applied voltage and internal gas pressure, allowing operational settings to be optimized. The GEMs were optimized to operate below laboratory atmospheric pressure, allowing lower applied voltages, thus reducing the risk of both electrical arcing and tearing of the thin detector windows. The instrument recorded 388 seconds of data and found highly uniform count distributions over both detector faces, in sharp contrast to the expected thermal line spectrum. This signal is attributed to X-ray fluorescence lines generated inside the spectrograph. The radiation is produced when thermal ionospheric particles are accelerated into the interior walls of the spectrograph by the high voltages of the detector windows. A fluorescence model was found to fit the flight data better than modeled supernova spectra. Post-flight testing and analysis revealed that electrons produce distinct signal on the detectors which can also be successfully modeled as fluorescence emission.

  5. Measurement Of Gas Electron Multiplier (GEM) Detector Characteristics

    NASA Astrophysics Data System (ADS)

    Park, Seongtae; Baldelomar, Edwin; Park, Kwangjune; Sosebee, Mark; White, Andy; Yu, Jaehoon

    2011-06-01

    The High Energy Physics group of the University of Texas at Arlington has been developing gas electron multiplier detectors to use them as sensitive gap detectors in digital hadron calorimeters for the International Linear Collider, a future high energy particle accelerator. For this purpose, we constructed numerous GEM detectors that employ double GEM layers. In this study, two kinds of prototype GEM detectors were tested; one with 28×28 cm2 active area double GEM structure with a 3 mm drift gap, a 1 mm transfer gap and a 1 mm induction gap and the other with two 3×3 cm2 GEM foils in the amplifier stage with a 5 mm drift gap, a 2 mm transfer gap and a 1 mm induction gap. The detectors' characteristics from exposure to high-energy charged particles and other radiations were measured using cosmic rays and 55Fe radioactive source. From the 55Fe tests, we observed two well separated characteristic X-ray emission peaks and confirmed the detectors' functionality. We also measured chamber gains to be over 6000 at a high voltage of 395 V across each GEM electrode. The responses to cosmic rays show the spectra that fit well to Landau distributions as expected from minimum ionizing particles.

  6. Proximity effects in cold gases of multiply charged atoms (Review)

    NASA Astrophysics Data System (ADS)

    Chikina, I.; Shikin, V.

    2016-07-01

    Possible proximity effects in gases of cold, multiply charged atoms are discussed. Here we deal with rarefied gases with densities nd of multiply charged (Z ≫ 1) atoms at low temperatures in the well-known Thomas-Fermi (TF) approximation, which can be used to evaluate the statistical properties of single atoms. In order to retain the advantages of the TF formalism, which is successful for symmetric problems, the external boundary conditions accounting for the finiteness of the density of atoms (donors), nd ≠ 0, are also symmetrized (using a spherical Wigner-Seitz cell) and formulated in a standard way that conserves the total charge within the cell. The model shows that at zero temperature in a rarefied gas of multiply charged atoms there is an effective long-range interaction Eproxi(nd), the sign of which depends on the properties of the outer shells of individual atoms. The long-range character of the interaction Eproxi is evaluated by comparing it with the properties of the well-known London dispersive attraction ELond(nd) < 0, which is regarded as a long-range interaction in gases. For the noble gases argon, krypton, and xenon Eproxi>0 and for the alkali and alkaline-earth elements Eproxi < 0. At finite temperatures, TF statistics manifests a new, anomalously large proximity effect, which reflects the tendency of electrons localized at Coulomb centers to escape into the continuum spectrum. The properties of thermal decay are interesting in themselves as they determine the important phenomenon of dissociation of neutral complexes into charged fragments. This phenomenon appears consistently in the TF theory through the temperature dependence of the different versions of Eproxi. The anomaly in the thermal proximity effect shows up in the following way: for T ≠ 0 there is no equilibrium solution of TS statistics for single multiply charged atoms in a vacuum when the effect is present. Instability is suppressed in a Wigner-Seitz model under the assumption that

  7. Electron interactions with positively and negatively multiply charged biomolecular clusters

    NASA Astrophysics Data System (ADS)

    Feketeová, Linda

    2012-07-01

    Interactions of positively and negatively multiply charged biomolecular clusters with low-energy electrons, from ~ 0 up to 50 eV of electron energy, were investigated in a high resolution Fourier-Transform Ion Cyclotron Resonance mass spectrometer equipped with an electrospray ionisation source. Electron-induced dissociation reactions of these clusters depend on the energy of the electrons, the size and the charge state of the cluster. The positively charged clusters [Mn+2H]2+ of zwitterionic betaines, M = (CH3)2XCH2CO2 (X = NCH3 and S), do capture an electron in the low electron energy region (< 10 eV). At higher electron energies neutral evaporation from the cluster becomes competitive with Coulomb explosion. In addition, a series of singly charged fragments arise from bond cleavage reactions, including decarboxylation and CH3 group transfer, due to the access of electronic excited states of the precursor ions. These fragmentation reactions depend on the type of betaine (X = NCH3 or S). For the negative dianionic clusters of tryptophan [Trp9-2H]2-, the important channel at low electron energies is loss of a neutral. Coulomb explosion competes from 19.8 eV and dominates at high electron energies. A small amount of [Trp2-H-NH3]- is observed at 21.8 eV.

  8. Does Chiropractic ‘Add Years to Life’?

    PubMed Central

    Morgan, Lon

    2004-01-01

    The chiropractic cliché “Chiropractic Adds Life to Years and Years to Life” was examined for validity. It was assumed that chiropractors themselves would be the best informed about the health benefits of chiropractic care. Chiropractors would therefore be most likely to receive some level of chiropractic care, and do so on a long-term basis. If chiropractic care significantly improves general health then chiropractors themselves should demonstrate longer life spans than the general population. Two separate data sources were used to examine chiropractic mortality rates. One source used obituary notices from past issues of Dynamic Chiropractic from 1990 to mid-2003. The second source used biographies from Who Was Who in Chiropractic – A Necrology covering a ten year period from 1969–1979. The two sources yielded a mean age at death for chiropractors of 73.4 and 74.2 years respectively. The mean ages at death of chiropractors is below the national average of 76.9 years and is below their medical doctor counterparts of 81.5. This review of mortality date found no evidence to support the claim that chiropractic care “Adds Years to Life.” PMID:17549121

  9. Subtractive transcriptomics : establishing polarity drives human endothelial morphogenesis

    SciTech Connect

    Glesne, D. A.; Zhang, W.; Mandava, S.; Ursos, L.; Buell, M. E.; Makowski, L.; Rodi, D. J.; Biosciences Division

    2006-04-15

    Although investigations of mature normal and tumor-derived capillaries have resulted in characterization of these structures at the phenotypic level, less is known regarding the initial molecular cues for cellular assembly of endothelial cells into human capillaries. Here, we employ a novel combination of microenvironmental manipulation and microarray data filtration over narrowly delineated temporal data series to identify the morphogenesis component apart from the proliferation component, as pooled human microvascular-derived endothelial cells are induced to form capillary-like structures in vitro in a murine tumor-derived matrix. The 217 morphogenesis-specific genes identified using this subtractive transcriptomics approach are mostly independent of the angiogenic proteins currently used as therapeutic targets for aberrant angiogenesis. Quantitative real-time PCR was used to validate 20% of these transcripts. Immunofluorescent analysis of proliferating and tube-forming cells validates at the protein level the morphogenesis-specific expression pattern of 16 of the 217 gene products identified. The transcripts that are selectively up-regulated in tube-forming endothelial cells reveal a temporal expression pattern of genes primarily associated with intracellular trafficking, guided migration, cytoskeletal reorganization, cellular adhesion, and proliferation inhibition. These data show that a sequential upregulation of genes that establish and maintain polarity occurs during migration and morphogenesis of in vitro human endothelial cells undergoing tubulogenesis; some of which may well be effective as novel antiangiogenic drug targets.

  10. Linear model for fast background subtraction in oligonucleotide microarrays

    PubMed Central

    2009-01-01

    Background One important preprocessing step in the analysis of microarray data is background subtraction. In high-density oligonucleotide arrays this is recognized as a crucial step for the global performance of the data analysis from raw intensities to expression values. Results We propose here an algorithm for background estimation based on a model in which the cost function is quadratic in a set of fitting parameters such that minimization can be performed through linear algebra. The model incorporates two effects: 1) Correlated intensities between neighboring features in the chip and 2) sequence-dependent affinities for non-specific hybridization fitted by an extended nearest-neighbor model. Conclusion The algorithm has been tested on 360 GeneChips from publicly available data of recent expression experiments. The algorithm is fast and accurate. Strong correlations between the fitted values for different experiments as well as between the free-energy parameters and their counterparts in aqueous solution indicate that the model captures a significant part of the underlying physical chemistry. PMID:19917117

  11. Removal of interference from fetal MEG by frequency dependent subtraction

    PubMed Central

    Vrba, J.; McCubbin, J.; Govindan, R.B.; Vairavan, S.; Murphy, P.; Preissl, H.; Lowery, C.L.; Eswaran, H.

    2011-01-01

    Fetal magnetoencephalography (fMEG) recordings are contaminated by maternal and fetal magnetocardiography (MCG) signals and by other biological and environmental interference. Currently, all methods for the attenuation of these signals are based on a time-domain approach. We have developed and tested a frequency dependent procedure for removal of MCG and other interference from the fMEG recordings. The method uses a set of reference channels and performs subtraction of interference in the frequency domain (SUBTR). The interference-free frequency domain signals are converted back to the time domain. We compare the performance of the frequency dependent approach with our present approach for MCG attenuation based on orthogonal projection (OP). SUBTR has an advantage over OP and similar template approaches because it removes not only the MCG but also other small amplitude biological interference, avoids the difficulties with inaccurate determination of the OP operator, provides more consistent and stable fMEG results, does not cause signal redistribution, and if references are selected judiciously, it does not reduce fMEG signal amplitude. SUBTR was found to perform well in simulations and on real fMEG recordings, and has a potential to improve the detection of fetal brain signals. The SUBTR removes interference without the need for a model of the individual interference sources. The method may be of interest for any sensor array noise reduction application where signal-free reference channels are available. PMID:21930216

  12. Dual energy subtraction method for breast calcification imaging

    NASA Astrophysics Data System (ADS)

    Koukou, Vaia; Martini, Niki; Fountos, George; Michail, Christos; Sotiropoulou, Panagiota; Bakas, Athanasios; Kalyvas, Nektarios; Kandarakis, Ioannis; Speller, Robert; Nikiforidis, George

    2017-03-01

    The aim of this work was to present an experimental dual energy (DE) method for the visualization of microcalcifications (μCs). A modified radiographic X-ray tube combined with a high resolution complementary metal-oxide-semiconductor (CMOS) active pixel sensor (APS) X-ray detector was used. A 40/70 kV spectral combination was filtered with 100 μm cadmium (Cd) and 1000 μm copper (Cu) for the low/high-energy combination. Homogenous and inhomogeneous breast phantoms and two calcification phantoms were constructed with various calcification thicknesses, ranging from 16 to 152 μm . Contrast-to-noise ratio (CNR) was calculated from the DE subtracted images for various entrance surface doses. A calcification thickness of 152 μm was visible, with mean glandular doses (MGD) in the acceptable levels (below 3 mGy). Additional post-processing on the DE images of the inhomogeneous breast phantom resulted in a minimum visible calcification thickness of 93 μm (MGD=1.62 mGy). The proposed DE method could potentially improve calcification visibility in DE breast calcification imaging.

  13. SPECKLE NOISE SUBTRACTION AND SUPPRESSION WITH ADAPTIVE OPTICS CORONAGRAPHIC IMAGING

    SciTech Connect

    Ren Deqing; Dou Jiangpei; Zhang Xi; Zhu Yongtian

    2012-07-10

    Future ground-based direct imaging of exoplanets depends critically on high-contrast coronagraph and wave-front manipulation. A coronagraph is designed to remove most of the unaberrated starlight. Because of the wave-front error, which is inherit from the atmospheric turbulence from ground observations, a coronagraph cannot deliver its theoretical performance, and speckle noise will limit the high-contrast imaging performance. Recently, extreme adaptive optics, which can deliver an extremely high Strehl ratio, is being developed for such a challenging mission. In this publication, we show that barely taking a long-exposure image does not provide much gain for coronagraphic imaging with adaptive optics. We further discuss a speckle subtraction and suppression technique that fully takes advantage of the high contrast provided by the coronagraph, as well as the wave front corrected by the adaptive optics. This technique works well for coronagraphic imaging with conventional adaptive optics with a moderate Strehl ratio, as well as for extreme adaptive optics with a high Strehl ratio. We show how to substrate and suppress speckle noise efficiently up to the third order, which is critical for future ground-based high-contrast imaging. Numerical simulations are conducted to fully demonstrate this technique.

  14. Microwave detection of breast tumors: comparison of skin subtraction algorithms

    NASA Astrophysics Data System (ADS)

    Fear, Elise C.; Stuchly, Maria A.

    2000-07-01

    Early detection of breast cancer is an important part of effective treatment. Microwave detection of breast cancer is of interest due to the contrast in dielectric properties of normal and malignant breast tissues. We are investigating a confocal microwave imaging system that adapts ideas from ground penetrating radar to breast cancer detection. In the proposed system, the patient lies prone with the breast extending through a hole in the examining table and encircled by an array of antennas. The breast is illuminated sequentially by each antenna with an ultrawideband signal, and the returns are recorded at the same antenna. Because the antennas are offset from the breast, the dominant component of the recorded returns is the reflection from the thin layer of breast skin. Two methods of reducing this reflection are compared, namely approximation of the signal with two time shifted, scaled and summed returns from a cylinder of skin, and subtraction of the mean of the set of aligned returns. Both approaches provide effective decrease of the skin signal, allowing for tumor detection.

  15. Expansion of capabilities of the short-duration wind tunnel with an opposing pressure multiplier

    NASA Astrophysics Data System (ADS)

    Shumskii, V. V.; Yaroslavtsev, M. I.

    2016-11-01

    A method for raising the maximum settling-chamber pressure in a short-duration wind tunnel equipped with pressure multipliers arranged in opposition to each other for stabilization of test gas parameters is proposed. For this purpose, a wind-tunnel design with an additional third pressure multiplier attached to the body of the second pressure multiplier was developed. The rod of the additional multiplier contacts the large-area piston stage of the second multiplier, and the pre-piston space being connected to the receiver. The inclusion of an additional pressure multiplier in the wind-tunnel design at the maximum attainable driver-gas pressure of 150-170 bar, defined by the standard industrial pressure of air used for filling wind-tunnel receivers with the driver gas, allows a two-fold increase in the maximum settling-chamber pressure, from 1100 to 2000-2200 bar. For raising the maximum settling-chamber pressure above 2000-2200 bar, the use of one additional pressure multiplier proved to be insufficient because, in the latter case, its becomes necessary to simultaneously raise the driver-gas pressure over 150-170 bar.

  16. The Origins of the SPAR-H Method's Performance Shaping Factor Multipliers

    SciTech Connect

    Ronald L. Boring; Harold S. Blackman

    2007-08-01

    The Standardized Plant Analysis Risk-Human Reliability Analysis (SPAR-H) method has proved to be a reliable, easy-to-use method for human reliability analysis. Calculation of human error probability (HEP) rates is especially straightforward, starting with pre-defined nominal error rates for cognitive vs. action oriented tasks, and incorporating performance shaping factor (PSF) multipliers upon those nominal error rates. SPAR-H uses eight PSFs with multipliers typically corresponding to nominal, degraded, and severely degraded human performance for individual PSFs. Additionally, some PSFs feature multipliers to reflect enhanced performance. Although SPAR-H enjoys widespread use among industry and regulators, current source documents on SPAR-H such as NUREG/CR-6883 do not provide a clear account of the origin of these multipliers. The present paper redresses this shortcoming and documents the historic development of the SPAR-H PSF multipliers, from the initial use of nominal error rates, to the selection of the eight PSFs, to the mapping of multipliers to available data sources such as a Technique for Human Error Rate Prediction (THERP). Where error rates were not readily derived from THERP and other sources, expert judgment was used to extrapolate appropriate values. In documenting key background information on the multipliers, this paper provides a much needed cross-reference for human reliability practitioners and researchers of SPAR-H to validate analyses and research findings.

  17. The functional architectures of addition and subtraction: Network discovery using fMRI and DCM.

    PubMed

    Yang, Yang; Zhong, Ning; Friston, Karl; Imamura, Kazuyuki; Lu, Shengfu; Li, Mi; Zhou, Haiyan; Wang, Haiyuan; Li, Kuncheng; Hu, Bin

    2017-03-27

    The neuronal mechanisms underlying arithmetic calculations are not well understood but the differences between mental addition and subtraction could be particularly revealing. Using fMRI and dynamic causal modeling (DCM), this study aimed to identify the distinct neuronal architectures engaged by the cognitive processes of simple addition and subtraction. Our results revealed significantly greater activation during subtraction in regions along the dorsal pathway, including the left inferior frontal gyrus (IFG), middle portion of dorsolateral prefrontal cortex (mDLPFC), and supplementary motor area (SMA), compared with addition. Subsequent analysis of the underlying changes in connectivity - with DCM - revealed a common circuit processing basic (numeric) attributes and the retrieval of arithmetic facts. However, DCM showed that addition was more likely to engage (numeric) retrieval-based circuits in the left hemisphere, while subtraction tended to draw on (magnitude) processing in bilateral parietal cortex, especially the right intraparietal sulcus (IPS). Our findings endorse previous hypotheses about the differences in strategic implementation, dominant hemisphere, and the neuronal circuits underlying addition and subtraction. Moreover, for simple arithmetic, our connectivity results suggest that subtraction calls on more complex processing than addition: auxiliary phonological, visual, and motor processes, for representing numbers, were engaged by subtraction, relative to addition. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc.

  18. Redefining the Whole: Common Errors in Elementary Preservice Teachers' Self-Authored Word Problems for Fraction Subtraction

    ERIC Educational Resources Information Center

    Dixon, Juli K.; Andreasen, Janet B.; Avila, Cheryl L.; Bawatneh, Zyad; Deichert, Deana L.; Howse, Tashana D.; Turner, Mercedes Sotillo

    2014-01-01

    A goal of this study was to examine elementary preservice teachers' (PSTs) ability to contextualize and decontextualize fraction subtraction by asking them to write word problems to represent fraction subtraction expressions and to choose prewritten word problems to support given fraction subtraction expressions. Three themes emerged from the…

  19. Ending up with Less: The Role of Working Memory in Solving Simple Subtraction Problems with Positive and Negative Answers

    ERIC Educational Resources Information Center

    Robert, Nicole D.; LeFevre, Jo-Anne

    2013-01-01

    Does solving subtraction problems with negative answers (e.g., 5-14) require different cognitive processes than solving problems with positive answers (e.g., 14-5)? In a dual-task experiment, young adults (N=39) combined subtraction with two working memory tasks, verbal memory and visual-spatial memory. All of the subtraction problems required…

  20. Toxic effect on tissues and differentially expressed genes in hepatopancreas identified by suppression subtractive hybridization of freshwater pearl mussel (Hyriopsis cumingii) following microcystin-LR challenge.

    PubMed

    Yang, Ziyan; Wu, Hongjuan; Li, Yuan

    2012-07-01

    Microcystins are a family of potent hepatotoxins produced by freshwater cyanobacteria and can cause animal intoxications and human diseases. In this study, the effect of microcystin-LR (MC-LR) on the tissues of freshwater pearl mussel (Hyriopsis cumingii) was evaluated and differentially expressed genes in the hepatopancreas of the mussel exposed to MC-LR were identified. HPLC analysis of cell extracts from various tissues of the mussel indicated that the hepatopancreas had the highest MC-LR levels (55.78 ± 6.73 μg g⁻¹ DW) after 15-day exposure. The MC-LR concentration in gill or muscle was an order of magnitude less than in hepatopancreas or gonad. Subtractive cDNA library was constructed by suppression subtractive hybridization (SSH), and ∼400 positive clones were sequenced, from which 98 high quality sequences were obtained by BLAST analysis. The screening identified numerous genes involved in apoptosis, signal transduction, cytoskeletal remodel, innate immunity, material and energy metabolism, translation and transcription which were extensively discussed. The results of this study add large amount of information to the mussel genome data, and for the first time present the basic data on toxicity effect of MC-LR on mussel.

  1. Configurable multiplier modules for an adaptive computing system

    NASA Astrophysics Data System (ADS)

    Pfänder, O. A.; Pfleiderer, H.-J.; Lachowicz, S. W.

    2006-09-01

    The importance of reconfigurable hardware is increasing steadily. For example, the primary approach of using adaptive systems based on programmable gate arrays and configurable routing resources has gone mainstream and high-performance programmable logic devices are rivaling traditional application-specific hardwired integrated circuits. Also, the idea of moving from the 2-D domain into a 3-D design which stacks several active layers above each other is gaining momentum in research and industry, to cope with the demand for smaller devices with a higher scale of integration. However, optimized arithmetic blocks in course-grain reconfigurable arrays as well as field-programmable architectures still play an important role. In countless digital systems and signal processing applications, the multiplication is one of the critical challenges, where in many cases a trade-off between area usage and data throughput has to be made. But the a priori choice of word-length and number representation can also be replaced by a dynamic choice at run-time, in order to improve flexibility, area efficiency and the level of parallelism in computation. In this contribution, we look at an adaptive computing system called 3-D-SoftChip to point out what parameters are crucial to implement flexible multiplier blocks into optimized elements for accelerated processing. The 3-D-SoftChip architecture uses a novel approach to 3-dimensional integration based on flip-chip bonding with indium bumps. The modular construction, the introduction of interfaces to realize the exchange of intermediate data, and the reconfigurable sign handling approach will be explained, as well as a beneficial way to handle and distribute the numerous required control signals.

  2. Computation of Floquet Multipliers Using an Iterative Method for Variational Equations

    NASA Astrophysics Data System (ADS)

    Nureki, Yu; Murashige, Sunao

    This paper proposes a new method to numerically obtain Floquet multipliers which characterize stability of periodic orbits of ordinary differential equations. For sufficiently smooth periodic orbits, we can compute Floquet multipliers using some standard numerical methods with enough accuracy. However, it has been reported that these methods may produce incorrect results under some conditions. In this work, we propose a new iterative method to compute Floquet multipliers using eigenvectors of matrix solutions of the variational equations. Numerical examples show effectiveness of the proposed method.

  3. A subsurface add-on for standard atomic force microscopes.

    PubMed

    Verbiest, G J; van der Zalm, D J; Oosterkamp, T H; Rost, M J

    2015-03-01

    The application of ultrasound in an Atomic Force Microscope (AFM) gives access to subsurface information. However, no commercially AFM exists that is equipped with this technique. The main problems are the electronic crosstalk in the AFM setup and the insufficiently strong excitation of the cantilever at ultrasonic (MHz) frequencies. In this paper, we describe the development of an add-on that provides a solution to these problems by using a special piezo element with a lowest resonance frequency of 2.5 MHz and by separating the electronic connection for this high frequency piezo element from all other connections. In this sense, we support researches with the possibility to perform subsurface measurements with their existing AFMs and hopefully pave also the way for the development of a commercial AFM that is capable of imaging subsurface features with nanometer resolution.

  4. A subsurface add-on for standard atomic force microscopes

    SciTech Connect

    Verbiest, G. J.; Zalm, D. J. van der; Oosterkamp, T. H.; Rost, M. J.

    2015-03-15

    The application of ultrasound in an Atomic Force Microscope (AFM) gives access to subsurface information. However, no commercially AFM exists that is equipped with this technique. The main problems are the electronic crosstalk in the AFM setup and the insufficiently strong excitation of the cantilever at ultrasonic (MHz) frequencies. In this paper, we describe the development of an add-on that provides a solution to these problems by using a special piezo element with a lowest resonance frequency of 2.5 MHz and by separating the electronic connection for this high frequency piezo element from all other connections. In this sense, we support researches with the possibility to perform subsurface measurements with their existing AFMs and hopefully pave also the way for the development of a commercial AFM that is capable of imaging subsurface features with nanometer resolution.

  5. Add-on gabapentin in the treatment of opiate withdrawal.

    PubMed

    Martínez-Raga, José; Sabater, Ana; Perez-Galvez, Bartolome; Castellano, Miguel; Cervera, Gaspar

    2004-05-01

    Gabapentin is an antiepileptic drug shown to be effective in the treatment of pain disorders and appears to be useful as well for several psychiatric disorders, including bipolar disorder, anxiety disorders, alcohol withdrawal and cocaine dependence. Gabapentin, at a dose of 600 mg three times a day, was evaluated as an add-on medication to a standard detoxification regime in seven heroin dependent individuals undergoing outpatient opiate withdrawal treatment. All seven patients successfully completed opiate detoxification and commenced opiate antagonist treatment with naltrexone on day five of withdrawal treatment, as scheduled. No adverse event was noted. Gabapentin appeared to lead a reduction in symptomatic medication and an overall beneficial effect on symptoms of heroin withdrawal.

  6. A clinical audit of thallium-technetium subtraction parathyroid scans.

    PubMed Central

    Samanta, A.; Wilson, B.; Iqbal, J.; Burden, A. C.; Walls, J.; Cosgriff, P.

    1990-01-01

    Eighty six consecutive thallium-technetium subtraction parathyroid scans performed over a three year period for hypercalcaemia have been evaluated. Twelve had chronic renal failure, 11 had hypercalcaemia due to non-hyperparathyroid causes and in 10 the imaging study was technically inadequate. The remaining 53 technically adequate studies performed for hypercalcaemia clinically thought to be possibly due to hyperparathyroidism have been analysed. Of 20 (38%) positive scans, 13 came to surgery (10 correctly localized parathyroid adenomas, 2 with multiple gland hyperplasia, and 1 papillary carcinoma of the thyroid). Of 33 (62%) negative scans, 9 had surgical exploration on the basis of strong clinical grounds and all had parathyroid adenomas. Multiple biochemical parameters have been assessed in relation to a positive outcome on scan. The adjusted calcium-phosphate product and the ratio of the adjusted calcium-phosphate product to creatinine (Ca x P/Cr) were both significantly lower in the scan positive group (P less than 0.01). The scan positive group had a significantly higher mean level of PTH (P less than 0.001) and lower mean level of phosphate (P less than 0.001). The present experience shows that parathyroid imaging is useful in localizing parathyroid adenomas in 50% of cases (10 out of 19). This figure is at the lower end of the range of previously published results. It is less effective in demonstrating multiple gland hyperplasia. The decision as to whether to undertake surgical exploration when the scan is negative has been based successfully on clinical judgement. We feel that an analysis of this nature is important, as it gives insights into the practical relevance of parathyroid imaging in the context of routine clinical work. PMID:2170959

  7. The Source for ADD/ADHD: Attention Deficit Disorder and Attention Deficit/Hyperactivity Disorder.

    ERIC Educational Resources Information Center

    Richard, Gail J.; Russell, Joy L.

    This book is intended for professionals who are responsible for designing and implementing educational programs for children with attention deficit disorders and attention deficit/hyperactivity disorder (ADD/ADHD). Chapters address: (1) myths and realities about ADD/ADHD; (2) definitions, disorders associated with ADD/ADHD, and federal educational…

  8. 24 CFR 983.206 - HAP contract amendments (to add or substitute contract units).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false HAP contract amendments (to add or... Contract § 983.206 HAP contract amendments (to add or substitute contract units). (a) Amendment to... substitute unit and must determine the reasonable rent for such unit. (b) Amendment to add contract units....

  9. 12 CFR 502.60 - When will OTS adjust, add, waive, or eliminate a fee?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 6 2014-01-01 2012-01-01 true When will OTS adjust, add, waive, or eliminate a... ASSESSMENTS AND FEES Fees § 502.60 When will OTS adjust, add, waive, or eliminate a fee? Under unusual circumstances, the Director may deem it necessary or appropriate to adjust, add, waive, or eliminate a fee....

  10. 24 CFR 983.206 - HAP contract amendments (to add or substitute contract units).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false HAP contract amendments (to add or... Contract § 983.206 HAP contract amendments (to add or substitute contract units). (a) Amendment to... substitute unit and must determine the reasonable rent for such unit. (b) Amendment to add contract units....

  11. 24 CFR 983.206 - HAP contract amendments (to add or substitute contract units).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 4 2014-04-01 2014-04-01 false HAP contract amendments (to add or... Contract § 983.206 HAP contract amendments (to add or substitute contract units). (a) Amendment to... substitute unit and must determine the reasonable rent for such unit. (b) Amendment to add contract units....

  12. 24 CFR 983.206 - HAP contract amendments (to add or substitute contract units).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false HAP contract amendments (to add or... Contract § 983.206 HAP contract amendments (to add or substitute contract units). (a) Amendment to... substitute unit and must determine the reasonable rent for such unit. (b) Amendment to add contract units....

  13. 5 CFR 330.105 - Instructions on how to add a vacancy announcement to USAJOBS.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 1 2013-01-01 2013-01-01 false Instructions on how to add a vacancy... Service § 330.105 Instructions on how to add a vacancy announcement to USAJOBS. An agency can find the instructions to add a vacancy announcement to USAJOBS on OPM's Web site at http://www.usajobs.gov....

  14. 12 CFR 502.60 - When will OTS adjust, add, waive, or eliminate a fee?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 6 2012-01-01 2012-01-01 false When will OTS adjust, add, waive, or eliminate... TREASURY ASSESSMENTS AND FEES Fees § 502.60 When will OTS adjust, add, waive, or eliminate a fee? Under unusual circumstances, the Director may deem it necessary or appropriate to adjust, add, waive,...

  15. 24 CFR 983.206 - HAP contract amendments (to add or substitute contract units).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 4 2012-04-01 2012-04-01 false HAP contract amendments (to add or... Contract § 983.206 HAP contract amendments (to add or substitute contract units). (a) Amendment to... substitute unit and must determine the reasonable rent for such unit. (b) Amendment to add contract units....

  16. 5 CFR 330.105 - Instructions on how to add a vacancy announcement to USAJOBS.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 1 2012-01-01 2012-01-01 false Instructions on how to add a vacancy... Service § 330.105 Instructions on how to add a vacancy announcement to USAJOBS. An agency can find the instructions to add a vacancy announcement to USAJOBS on OPM's Web site at http://www.usajobs.gov....

  17. 12 CFR 502.60 - When will OTS adjust, add, waive, or eliminate a fee?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false When will OTS adjust, add, waive, or eliminate... TREASURY ASSESSMENTS AND FEES Fees § 502.60 When will OTS adjust, add, waive, or eliminate a fee? Under unusual circumstances, the Director may deem it necessary or appropriate to adjust, add, waive,...

  18. 12 CFR 502.60 - When will OTS adjust, add, waive, or eliminate a fee?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 5 2011-01-01 2011-01-01 false When will OTS adjust, add, waive, or eliminate... TREASURY ASSESSMENTS AND FEES Fees § 502.60 When will OTS adjust, add, waive, or eliminate a fee? Under unusual circumstances, the Director may deem it necessary or appropriate to adjust, add, waive,...

  19. 5 CFR 330.105 - Instructions on how to add a vacancy announcement to USAJOBS.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 1 2014-01-01 2014-01-01 false Instructions on how to add a vacancy... Service § 330.105 Instructions on how to add a vacancy announcement to USAJOBS. An agency can find the instructions to add a vacancy announcement to USAJOBS on OPM's Web site at http://www.usajobs.gov....

  20. 12 CFR 502.60 - When will OTS adjust, add, waive, or eliminate a fee?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 6 2013-01-01 2012-01-01 true When will OTS adjust, add, waive, or eliminate a... ASSESSMENTS AND FEES Fees § 502.60 When will OTS adjust, add, waive, or eliminate a fee? Under unusual circumstances, the Director may deem it necessary or appropriate to adjust, add, waive, or eliminate a fee....

  1. College Students with Attention Deficit Disorder (ADD): Implications for Learning Assistance Professionals.

    ERIC Educational Resources Information Center

    Eaton, Shevawn; Wyland, Sharon

    1996-01-01

    Examines the research and theory about attention deficit disorder (ADD) in college students and discusses how learning assistance professionals can better assist college students with ADD. Appended in this article are strategies for faculty/learning center professionals in accommodating students with ADD and a list of suggested readings. Contains…

  2. Evaluation of a Transitional Training Program for Mentally Retarded, Multiply Handicapped High School Students.

    ERIC Educational Resources Information Center

    O'Brien, Patrick J.; Schiller, William J.

    1979-01-01

    A comparative study was made of 18 mentally retarded, multiply handicapped high school students who attended a work study program and 12 students who were traditionally serviced in the academic program. (CL)

  3. Design of Pipeline Multiplier Based on Modified Booth's Algorithm and Wallace Tree

    NASA Astrophysics Data System (ADS)

    Yao, Aihong; Li, Ling; Sun, Mengzhe

    A design of 32*32 bit pipelined multiplier is presented in this paper. The proposed multiplier is based on the modified booth algorithm and Wallace tree structure. In order to improve the throughput rate of the multiplier, pipeline architecture is introduced to the Wallace tree. Carry Select Adder is deployed to reduce the propagation delay of carry signal for the final level 64-bit adder. The multiplier is fully implemented with Verilog HDL and synthesized successfully with Quartus II. The experiment result shows that the resource consumption and power consumption is reduced to 2560LE and 120mW, the operating frequency is improved from 136.21MHz to 165.07MHz.

  4. Cost-efficient design of a quantum multiplier-accumulator unit

    NASA Astrophysics Data System (ADS)

    Babu, Hafiz Md. Hasan

    2017-01-01

    This paper proposes a cost-efficient quantum multiplier-accumulator unit. The paper also presents a fast multiplication algorithm and designs a novel quantum multiplier device based on the proposed algorithm with the optimum time complexity as multiplier is the major device of a multiplier-accumulator unit. We show that the proposed multiplication technique has time complexity O((3 log2n)+1), whereas the best known existing technique has O(n log2 n), where n is the number of qubits. In addition, our design proposes three new quantum circuits: a circuit representing a quantum full-adder, a circuit known as quantum ANDing circuit, which performs the ANDing operation and a circuit presenting quantum accumulator. Moreover, the proposed quantum multiplier-accumulator unit is the first ever quantum multiplier-accumulator circuit in the literature till now, which has reduced garbage outputs and ancillary inputs to a great extent. The comparative study shows that the proposed quantum multiplier performs better than the existing multipliers in terms of depth, quantum gates, delays, area and power with the increasing number of qubits. Moreover, we design the proposed quantum multiplier-accumulator unit, which performs better than the existing ones in terms of hardware and delay complexities, e.g., the proposed (n× n)—qubit quantum multiplier-accumulator unit requires O(n2) hardware and O(log2n) delay complexities, whereas the best known existing quantum multiplier-accumulator unit requires O(n3) hardware and O((n-1)2 +1+n) delay complexities. In addition, the proposed design achieves an improvement of 13.04, 60.08 and 27.2% for 4× 4, 7.87, 51.8 and 27.1% for 8× 8, 4.24, 52.14 and 27% for 16× 16, 2.19, 52.15 and 27.26% for 32 × 32 and 0.78, 52.18 and 27.28% for 128 × 128-qubit multiplications over the best known existing approach in terms of number of quantum gates, ancillary inputs and garbage outputs, respectively. Moreover, on average, the proposed design gains an

  5. Spectral subtraction-based speech enhancement for cochlear implant patients in background noise

    NASA Astrophysics Data System (ADS)

    Yang, Li-Ping; Fu, Qian-Jie

    2005-03-01

    A single-channel speech enhancement algorithm utilizing speech pause detection and nonlinear spectral subtraction is proposed for cochlear implant patients in the present study. The spectral subtraction algorithm estimates the short-time spectral magnitude of speech by subtracting the estimated noise spectral magnitude from the noisy speech spectral magnitude. The artifacts produced by spectral subtraction (such as ``musical noise'') were significantly reduced by combining variance-reduced gain function and spectral flooring. Sentence recognition by seven cochlear implant subjects was tested under different noisy listening conditions (speech-shaped noise and 6-talker speech babble at +9, +6, +3, and 0 dB SNR) with and without the speech enhancement algorithm. For speech-shaped noise, performance for all subjects at all SNRs was significantly improved by the speech enhancement algorithm; for speech babble, performance was only modestly improved. The results suggest that the proposed speech enhancement algorithm may be beneficial for implant users in noisy listening. .

  6. Doubles counting of highly multiplying items in reflective surroundings

    SciTech Connect

    Croft, Stephen; Evans, Louise G; Schear, Melissa A; Tobin, Stephen J

    2010-11-18

    When a neutrons are counted from a spontaneously fissile multiplying item in a reflecting environment the temporal behavior of the correlated signal following neutron birth is complex. At early times the signal is dominated by prompt fission events coming from spontaneous fission bursts and also from prompt fast-neutron induced fission events. At later times neutrons 'returning' from the surroundings induce fission and give rise to an additional chain of correlated events. The prompt and returning components probe the fissile and fertile constituents of the item in different ways and it is potentially beneficial to exploit this fact. In this work we look at how the two components can be represented using a linear combination of two simple functions. Fitting of the composite function to the capture time distribution represents one way of quantifying the proportion of each contribution. Another approach however is to use a dual shift register analysis where after each triggering event two coincidence gates are opened, one close to the trigger that responds preferentially to the prompt dynamics and one later in time which is more sensitive to the returning neutron induced events. To decide on the best gate positions and gate widths and also to estimate the counting precision we can use the analytical fit to work out the necessary gate utilization factors which are required in both these calculations. In this work, we develop the approach. Illustrative examples are given using spent Low Enriched Uranium (LEU) Pressurized light Water Reactor (LWR) fuel assemblies submersed in borated water and counted in a ring of {sup 3}He gas-filled proportional counters. In this case the prompt component is dominated by {sup 244}Cm spontaneous fission and induced fast neutron fission in for example {sup 238}U while the returning low energy neutrons induce fission mainly in the fissile nuclides such as {sup 239}Pu, {sup 241}Pu and {sup 235}U. One requirement is to calculate the Random

  7. Productivity cost calculations in health economic evaluations: correcting for compensation mechanisms and multiplier effects.

    PubMed

    Krol, Marieke; Brouwer, Werner B F; Severens, Johan L; Kaper, Janneke; Evers, Silvia M A A

    2012-12-01

    Productivity costs related to paid work are commonly calculated in economic evaluations of health technologies by multiplying the relevant number of work days lost with a wage rate estimate. It has been argued that actual productivity costs may either be lower or higher than current estimates due to compensation mechanisms and/or multiplier effects (related to team dependency and problems with finding good substitutes in cases of absenteeism). Empirical evidence on such mechanisms and their impact on productivity costs is scarce, however. This study aims to increase knowledge on how diminished productivity is compensated within firms. Moreover, it aims to explore how compensation and multiplier effects potentially affect productivity cost estimates. Absenteeism and compensation mechanisms were measured in a randomized trial among Dutch citizens examining the cost-effectiveness of reimbursement for smoking cessation treatment. Multiplier effects were extracted from published literature. Productivity costs were calculated applying the Friction Cost Approach. Regular estimates were subsequently adjusted for (i) compensation during regular working hours, (ii) job dependent multipliers and (iii) both compensation and multiplier effects. A total of 187 respondents included in the trial were useful for inclusion in this study, based on being in paid employment, having experienced absenteeism in the preceding six months and completing the questionnaire on absenteeism and compensation mechanisms. Over half of these respondents stated that their absenteeism was compensated during normal working hours by themselves or colleagues. Only counting productivity costs not compensated in regular working hours reduced the traditional estimate by 57%. Correcting for multiplier effects increased regular estimates by a quarter. Combining both impacts decreased traditional estimates by 29%. To conclude, large amounts of lost production are compensated in normal hours. Productivity costs

  8. Real-time out-of-plane artifact subtraction tomosynthesis imaging using prior CT for scanning beam digital x-ray system

    SciTech Connect

    Wu, Meng; Fahrig, Rebecca

    2014-11-01

    Purpose: The scanning beam digital x-ray system (SBDX) is an inverse geometry fluoroscopic system with high dose efficiency and the ability to perform continuous real-time tomosynthesis in multiple planes. This system could be used for image guidance during lung nodule biopsy. However, the reconstructed images suffer from strong out-of-plane artifact due to the small tomographic angle of the system. Methods: The authors propose an out-of-plane artifact subtraction tomosynthesis (OPAST) algorithm that utilizes a prior CT volume to augment the run-time image processing. A blur-and-add (BAA) analytical model, derived from the project-to-backproject physical model, permits the generation of tomosynthesis images that are a good approximation to the shift-and-add (SAA) reconstructed image. A computationally practical algorithm is proposed to simulate images and out-of-plane artifacts from patient-specific prior CT volumes using the BAA model. A 3D image registration algorithm to align the simulated and reconstructed images is described. The accuracy of the BAA analytical model and the OPAST algorithm was evaluated using three lung cancer patients’ CT data. The OPAST and image registration algorithms were also tested with added nonrigid respiratory motions. Results: Image similarity measurements, including the correlation coefficient, mean squared error, and structural similarity index, indicated that the BAA model is very accurate in simulating the SAA images from the prior CT for the SBDX system. The shift-variant effect of the BAA model can be ignored when the shifts between SBDX images and CT volumes are within ±10 mm in the x and y directions. The nodule visibility and depth resolution are improved by subtracting simulated artifacts from the reconstructions. The image registration and OPAST are robust in the presence of added respiratory motions. The dominant artifacts in the subtraction images are caused by the mismatches between the real object and the prior CT

  9. Tailed pooled suppression subtractive hybridization (PSSH) adaptors do not alter efficiency.

    PubMed

    Gerrish, Robert S; Gill, Steven R

    2010-11-01

    Suppression Subtractive Hybridization (SSH) and its derivative, Pooled Suppression Subtractive hybridization (PSSH), are powerful tools used to study variances larger than ~100 bp in prokaryotic genome structure. The initial steps involve ligating an oligonucleotide of known sequence (the "adaptor") to a fragmented genome to facilitate amplification, subtraction and downstream sequencing. SSH results in the creation of a library of unique DNA fragments which have been traditionally analyzed via Sanger sequencing. Numerous next generation sequencing technologies have entered the market yet SSH is incompatible with these platforms. This is due to the high level of sequence conservation of the oligonucleotide used for SSH. This rigid adherence is partly because it has yet to be determined if alteration of this oligonucleotide will have a deleterious impact on subtraction efficiency. The subtraction occurs when non-unique fragments are inhibited by a secondary self-pairing structure which requires exact nucleotide sequence. We determine if appending custom sequence to the 5' terminal ends of these oligonucleotides during the nested PCR stages of PSSH will reduce subtraction efficiency. We compare a pool of ten S. aureus clinical isolates with a standard PSSH and custom tailed-PSSH. We detected no statistically significant difference between their subtraction efficiencies. Our observations suggest that the adaptor's terminal ends may be labeled during the nested PCR step. This produces libraries labeled with custom sequence. This does not lead to loss of subtraction efficiency and would be invaluable for groups wishing to combine SSH or PSSH with their own downstream applications, such as a high throughput sequencing platform.

  10. Subtraction radiography for the diagnosis of bone lesions in dogs. Report for 1982-1984

    SciTech Connect

    Rethman, M.P.; Ruttiman, U.E.; O'Neal, R.B.; Webber, R.L.; Davis, A.A.

    1984-05-31

    Resolution of osseous wounds utilizing conventional radiographic techniques is dependent upon favorable angulation without superimposition of dense anatomical structures. A technique of computer subtraction utilizing sequential radiographs has been demonstrated to enhance visualization of such defects in dry skulls, but usefulness in live animals had heretofore not been demonstrated. This investigation demonstrated the usefulness of computer subtraction radiography in live animals, both error rate and diagnostic time being reduced significantly.

  11. Value of blood-pool subtraction in cardiac indium-111-labeled platelet imaging

    SciTech Connect

    Machac, J.; Vallabhajosula, S.; Goldman, M.E.; Goldsmith, S.J.; Palestro, C.; Strashun, A.; Vaquer, R.; Phillips, R.A.; Fuster, V. )

    1989-09-01

    Blood-pool subtraction has been proposed to enhance {sup 111}In-labeled platelet imaging of intracardiac thrombi. We tested the accuracy of labeled platelet imaging, with and without blood-pool subtraction, in ten subjects with cardiac thrombi of varying age, eight with endocarditis being treated with antimicrobial therapy and ten normal controls. Imaging was performed early after labeled platelet injection (24 hr or less) and late (48 hr or more). Blood-pool subtraction was carried out. All images were graded subjectively by four experienced, blinded readers. Detection accuracy was measured by the sensitivity at three fixed levels of specificity estimated from receiver operator characteristic curve analysis and tested by three-way analysis of variance. Detection accuracy was generally improved on delayed images. Blood-pool subtraction did not improve accuracy. Although blood-pool subtraction increased detection sensitivity, this was offset by decreased specificity. For this population studied, blood-pool subtraction did not improve subjective detection of abnormal platelet deposition by 111In platelet imaging.

  12. ADD and the College Student: A Guide for High School and College Students with Attention Deficit Disorder. Revised Edition.

    ERIC Educational Resources Information Center

    Quinn, Patricia O., Ed.

    This handbook contains practical information and advice to help students with Attention Deficit Disorder (ADD) transition from high school to college. Part 1 provides an introduction to ADD and includes a questionnaire identifying the characteristics of a person with ADD. Part 2 describes life with ADD. It explains how ADD can affect high school…

  13. Does aquaculture add resilience to the global food system?

    PubMed

    Troell, Max; Naylor, Rosamond L; Metian, Marc; Beveridge, Malcolm; Tyedmers, Peter H; Folke, Carl; Arrow, Kenneth J; Barrett, Scott; Crépin, Anne-Sophie; Ehrlich, Paul R; Gren, Asa; Kautsky, Nils; Levin, Simon A; Nyborg, Karine; Österblom, Henrik; Polasky, Stephen; Scheffer, Marten; Walker, Brian H; Xepapadeas, Tasos; de Zeeuw, Aart

    2014-09-16

    Aquaculture is the fastest growing food sector and continues to expand alongside terrestrial crop and livestock production. Using portfolio theory as a conceptual framework, we explore how current interconnections between the aquaculture, crop, livestock, and fisheries sectors act as an impediment to, or an opportunity for, enhanced resilience in the global food system given increased resource scarcity and climate change. Aquaculture can potentially enhance resilience through improved resource use efficiencies and increased diversification of farmed species, locales of production, and feeding strategies. However, aquaculture's reliance on terrestrial crops and wild fish for feeds, its dependence on freshwater and land for culture sites, and its broad array of environmental impacts diminishes its ability to add resilience. Feeds for livestock and farmed fish that are fed rely largely on the same crops, although the fraction destined for aquaculture is presently small (∼4%). As demand for high-value fed aquaculture products grows, competition for these crops will also rise, as will the demand for wild fish as feed inputs. Many of these crops and forage fish are also consumed directly by humans and provide essential nutrition for low-income households. Their rising use in aquafeeds has the potential to increase price levels and volatility, worsening food insecurity among the most vulnerable populations. Although the diversification of global food production systems that includes aquaculture offers promise for enhanced resilience, such promise will not be realized if government policies fail to provide adequate incentives for resource efficiency, equity, and environmental protection.

  14. Does aquaculture add resilience to the global food system?

    PubMed Central

    Troell, Max; Naylor, Rosamond L.; Metian, Marc; Beveridge, Malcolm; Tyedmers, Peter H.; Folke, Carl; Arrow, Kenneth J.; Barrett, Scott; Crépin, Anne-Sophie; Ehrlich, Paul R.; Gren, Åsa; Kautsky, Nils; Levin, Simon A.; Nyborg, Karine; Österblom, Henrik; Polasky, Stephen; Scheffer, Marten; Walker, Brian H.; Xepapadeas, Tasos; de Zeeuw, Aart

    2014-01-01

    Aquaculture is the fastest growing food sector and continues to expand alongside terrestrial crop and livestock production. Using portfolio theory as a conceptual framework, we explore how current interconnections between the aquaculture, crop, livestock, and fisheries sectors act as an impediment to, or an opportunity for, enhanced resilience in the global food system given increased resource scarcity and climate change. Aquaculture can potentially enhance resilience through improved resource use efficiencies and increased diversification of farmed species, locales of production, and feeding strategies. However, aquaculture’s reliance on terrestrial crops and wild fish for feeds, its dependence on freshwater and land for culture sites, and its broad array of environmental impacts diminishes its ability to add resilience. Feeds for livestock and farmed fish that are fed rely largely on the same crops, although the fraction destined for aquaculture is presently small (∼4%). As demand for high-value fed aquaculture products grows, competition for these crops will also rise, as will the demand for wild fish as feed inputs. Many of these crops and forage fish are also consumed directly by humans and provide essential nutrition for low-income households. Their rising use in aquafeeds has the potential to increase price levels and volatility, worsening food insecurity among the most vulnerable populations. Although the diversification of global food production systems that includes aquaculture offers promise for enhanced resilience, such promise will not be realized if government policies fail to provide adequate incentives for resource efficiency, equity, and environmental protection. PMID:25136111

  15. Climatic Drivers of Past Antarctic Ice Sheet Evolution Add Nonlinearly

    NASA Astrophysics Data System (ADS)

    Tigchelaar, M.; Timmermann, A.; Pollard, D.; Friedrich, T.; Heinemann, M.

    2015-12-01

    The Antarctic ice sheet has varied substantially in shape and volume in the past, with evidence for strong regional differences in evolution history. Recent observations of change in the Antarctic environment indicate that different regions respond differently to ongoing changes in global climate -- over the West Antarctic Ice Sheet strong increases in sub-shelf melt rates indicate a sensitivity to changes in ocean temperature and circulation, while in East Antarctica the mass balance is increasingly positive due to an increase in accumulation in response to rising temperatures. Modeling the long term evolution of the Antarctic ice sheet can help address questions about its regional sensitivity to external forcing. We have conducted experiments with an established ice sheet model over the last eight glacial cycles using spatially and temporally varying climate forcing from an EMIC. These simulations indicate a glacial-interglacial amplitude of ~11m SLE. Using a series of sensitivity experiments we address the dominant climatic forcing of this evolution. While sea level changes are the main driver of grounding line movement, they alone are not sufficient to explain the full glacial amplitude. Local insolation changes contribute to the initiation of terminations, while accumulation and sub-shelf melt changes feed back positively and negatively respectively onto the ice sheet evolution. This implies that climatic drivers add nonlinearly and the full spectrum of climate forcing needs to be considered when evaluating the sensitivity of the Antarctic ice sheet to past and future climate change.

  16. Converting between [Degrees]C and [Degrees]F: A Teachable Moment

    ERIC Educational Resources Information Center

    Day, Lawrence

    2007-01-01

    Converting between degrees Celsius and degrees Fahrenheit isn't difficult. Remembering when to multiply by 5/9 or 9/5 and whether you have to add 32 or subtract 32 makes it fairly easy. Sometimes, though, fairly easy isn't easy enough. Students have trouble remembering the order of operations: "Do I add or subtract 32, and is that before or after…

  17. FamNet: A Framework to Identify Multiplied Modules Driving Pathway Expansion in Plants1

    PubMed Central

    Tohge, Takayuki; Klie, Sebastian; Fernie, Alisdair R.

    2016-01-01

    Gene duplications generate new genes that can acquire similar but often diversified functions. Recent studies of gene coexpression networks have indicated that, not only genes, but also pathways can be multiplied and diversified to perform related functions in different parts of an organism. Identification of such diversified pathways, or modules, is needed to expand our knowledge of biological processes in plants and to understand how biological functions evolve. However, systematic explorations of modules remain scarce, and no user-friendly platform to identify them exists. We have established a statistical framework to identify modules and show that approximately one-third of the genes of a plant’s genome participate in hundreds of multiplied modules. Using this framework as a basis, we implemented a platform that can explore and visualize multiplied modules in coexpression networks of eight plant species. To validate the usefulness of the platform, we identified and functionally characterized pollen- and root-specific cell wall modules that multiplied to confer tip growth in pollen tubes and root hairs, respectively. Furthermore, we identified multiplied modules involved in secondary metabolite synthesis and corroborated them by metabolite profiling of tobacco (Nicotiana tabacum) tissues. The interactive platform, referred to as FamNet, is available at http://www.gene2function.de/famnet.html. PMID:26754669

  18. An investigation of self-subtraction holography in LiNbO3

    NASA Technical Reports Server (NTRS)

    Vahey, D. W.; Kenan, R. P.; Hartman, N. F.; Sherman, R. C.

    1981-01-01

    A sample having self subtraction characteristics that were very promising was tested in depth: hologram formation times were on the order of 150 sec, the null signal was less than 2.5% of the peak signal, and no fatigue nor instability was detected over the span of the experiments. Another sample, fabricated with, at most, slight modifications did not perform nearly as well. In all samples, attempts to improve self subtraction characteristics by various thermal treatments had no effects or adverse effects, with one exception in which improvement was noted after a time delay of several days. A theory developed to describe self subtraction showed the observed decrease in beam intensity with time, but the shape of the predicted decay curve was oscillatory in contrast to the exponential like decay observed. The theory was also inadequate to account for the experimental sensitivity of self subtraction to the Bragg angle of the hologram. It is concluded that self subtraction is a viable method for optical processing systems requiring background discrimination.

  19. Speech enhancement using parametric spectral subtraction combined with generalized sidelobe canceller

    NASA Astrophysics Data System (ADS)

    Cho, Jaeyoun; Krishnamurthy, Ashok

    2003-10-01

    Speech enhancement is an important problem with applications in hearing aid design, speech recognition, speech coding, etc. Parametric spectral subtraction is a common method for speech enhancement when only a single channel of data is available. On the other hand, beamforming methods can be used when multiple channels of spatially separated data are available, such as from a microphone array. In previous work, we have shown that spectral subtraction combined with spatial averaging from multiple microphones leads to improvements in speech SNR and reduction of musical noise compared with either method used alone. In this talk, we extend the previous work to combine parametric spectral subtraction with adaptive beamforming, specifically the generalized sidelobe canceller. The proposed parametric spectral subtraction method determines the parameters adaptively so as to minimize speech distortion. In addition, it is shown that the major drawback of spectral subtraction, so-called musical noise, can be diminished by adaptive beamforming process. We show that the method leads to a reduction of musical noise and results in the enhanced speech having better quality and intelligibility.

  20. Subtraction CT angiography for the detection of intracranial aneurysms: A meta-analysis

    PubMed Central

    FENG, TIAN-YING; HAN, XUE-FENG; LANG, RUI; WANG, FEI; WU, QIONG

    2016-01-01

    The aim of this meta-analysis was to investigate the accuracy of subtraction computed tomography angiography (CTA) for diagnosing intracranial aneurysms. A systematic literature search up to January 1, 2013 was performed in PubMed. Two independent reviewers selected 8 studies that compared subtraction CTA with digital subtraction angiography. Data from the studies were used to construct a 2×2 contingency table on a per-patient basis in ≥5 diseased and 5 non-diseased patients, with additional data on a per-aneurysm basis. Overall, subtraction CTA had a pooled sensitivity of 99% [95% confidence interval (CI), 95–100%] and specificity of 94% (95% CI, 86–97%) for detecting and ruling out cerebral aneurysms, respectively, on a per-patient basis. On a per-aneurysm basis, the pooled sensitivity was 96% (95% CI, 90–99%), and the specificity was 91% (95% CI, 85–95%). In conclusion, subtraction CTA is a highly sensitive, specific and non-invasive method for the diagnosis and evaluation of intracranial aneurysms. PMID:27168830

  1. Additive-subtractive phase-modulated electronic speckle interferometry: analysis of fringe visibility.

    PubMed

    Pouet, B F; Krishnaswamy, S

    1994-10-01

    Fringe-visibility issues of additive-subtractive phase-modulated (ASPM) electronic speckle pattern interferometry (ESPI) are explored. ASPM ESPI is a three-step method in which additive-speckle images are acquired rapidly in an analog fashion in every frame of a video sequence, a speckle phase modulation is intentionally introduced between frames, and a digital subtraction of consecutive pairs of additive-speckle images is performed. We show that this scheme has the good high-frequency noise immunity associated with additive-ESPI techniques as well as the good fringe visibility associated with subtractive-ESPI techniques. The method has better fringe visibility than can be obtained with purely additive ESPI and also does not suffer from the fringe distortions that can occur with subtractive ESPI in the presence of high-frequency noise. We show that even if full speckle decorrelation were to occur between the two additive speckle images that are to be subtracted, the visibility of ASPM ESPI fringes can be made to approach unity by suitable adjustment of the reference-to-object beam-intensity ratio.

  2. Automated contralateral subtraction of dental panoramic radiographs for detecting abnormalities in paranasal sinus

    NASA Astrophysics Data System (ADS)

    Hara, Takeshi; Mori, Shintaro; Kaneda, Takashi; Hayashi, Tatsuro; Katsumata, Akitoshi; Fujita, Hiroshi

    2011-03-01

    Inflammation in the paranasal sinus is often observed in seasonal allergic rhinitis or with colds, but is also an indication for odontogenic tumors, carcinoma of the maxillary sinus or a maxillary cyst. The detection of those findings in dental panoramic radiographs is not difficult for radiologists, but general dentists may miss the findings since they focus on treatments of teeth. The purpose of this work is to develop a contralateral subtraction method for detecting the odontogenic sinusitis region on dental panoramic radiographs. We developed a contralateral subtraction technique in paranasal sinus region, consisting of 1) image filtering of the smoothing and sobel operation for noise reduction and edge extraction, 2) image registration of mirrored image by using mutual information, and 3) image display method of subtracted pixel data. We employed 56 cases (24 normal and 32 abnormal). The abnormal regions and the normal cases were verified by a board-certified radiologist using CT scans. Observer studies with and without subtraction images were performed for 9 readers. The true-positive rate at a 50% confidence level in 7 out of 9 readers was improved, but there was no statistical significance in the difference of area-under-curve (AUC) in each radiologist. In conclusion, the contralateral subtraction images of dental panoramic radiographs may improve the detection rate of abnormal regions in paranasal sinus.

  3. New perspectives for diagnosis of nodular goiter by technetium-thallium subtraction scanning

    SciTech Connect

    Katagiri, M.; Harada, T.; Fukunaga, M.; Furukawa, J.; Yamane, Y.; Yasuda, K.; Yanagimoto, S.; Tomomitsu, T.; Otsuka, N.; Morita, R. )

    1989-12-01

    To improve the scintigraphic differential diagnosis of thyroid nodules, Tc-99m pertechnetate-Tl-201 Cl subtraction scintigraphy (Tc-Tl subtraction scanning) was performed in 106 patients with various histologically proven thyroid nodules. Results were evaluated by comparison with surgical findings and preoperative ultrasonographic results. Thyroid nodules were more successfully detected by Tc-Tl subtraction scanning than by either Tc-99m pertechnetate or Tl-201 Cl scintigraphy alone. Detection of nodules was further improved when images recorded by the three methods were integrally observed (sensitivity 83%, accuracy 89%), with detectability approaching that of ultrasonography. False-positive or -negative Tc-Tl subtraction scans were obtained principally when multiple nodules were present (7 cases) or when no discrepancy existed between the accumulations of Tc-99m pertechnetate and Tl-201 Cl (18 cases). Most colloid nodules exhibited irregular margins, heterogeneous internal accumulations of Tl-201 Cl, and distorted shapes on Tc-Tl subtraction scans, while the majority of adenoma were oval-shaped with smooth margins. Carcinoma were characterized by homogeneous internal accumulation of Tl-201 Cl and distorted shapes.

  4. Embedding objects during 3D printing to add new functionalities.

    PubMed

    Yuen, Po Ki

    2016-07-01

    A novel method for integrating and embedding objects to add new functionalities during 3D printing based on fused deposition modeling (FDM) (also known as fused filament fabrication or molten polymer deposition) is presented. Unlike typical 3D printing, FDM-based 3D printing could allow objects to be integrated and embedded during 3D printing and the FDM-based 3D printed devices do not typically require any post-processing and finishing. Thus, various fluidic devices with integrated glass cover slips or polystyrene films with and without an embedded porous membrane, and optical devices with embedded Corning(®) Fibrance™ Light-Diffusing Fiber were 3D printed to demonstrate the versatility of the FDM-based 3D printing and embedding method. Fluid perfusion flow experiments with a blue colored food dye solution were used to visually confirm fluid flow and/or fluid perfusion through the embedded porous membrane in the 3D printed fluidic devices. Similar to typical 3D printed devices, FDM-based 3D printed devices are translucent at best unless post-polishing is performed and optical transparency is highly desirable in any fluidic devices; integrated glass cover slips or polystyrene films would provide a perfect optical transparent window for observation and visualization. In addition, they also provide a compatible flat smooth surface for biological or biomolecular applications. The 3D printed fluidic devices with an embedded porous membrane are applicable to biological or chemical applications such as continuous perfusion cell culture or biocatalytic synthesis but without the need for any post-device assembly and finishing. The 3D printed devices with embedded Corning(®) Fibrance™ Light-Diffusing Fiber would have applications in display, illumination, or optical applications. Furthermore, the FDM-based 3D printing and embedding method could also be utilized to print casting molds with an integrated glass bottom for polydimethylsiloxane (PDMS) device replication

  5. Fragmentation of multiply-charged intact protein ions using MALDI TOF-TOF mass spectrometry.

    PubMed

    Liu, Zhaoyang; Schey, Kevin L

    2008-02-01

    Top down proteomics in a TOF-TOF instrument was further explored by examining the fragmentation of multiply charged precursors ions generated by matrix-assisted laser desorption ionization. Evaluation of sample preparation conditions allowed selection of solvent/matrix conditions and sample deposition methods to produce sufficiently abundant doubly and triply charged precursor ions for subsequent CID experiments. As previously reported, preferential cleavage was observed at sites C-terminal to acidic residues and N-terminal to proline residues for all ions examined. An increase in nonpreferential fragmentation as well as additional low mass product ions was observed in the spectra from multiply charged precursor ions providing increased sequence coverage. This enhanced fragmentation from multiply charged precursor ions became increasingly important with increasing protein molecular weight and facilitates protein identification using database searching algorithms. The useable mass range for MALDI TOF-TOF analysis of intact proteins has been expanded to 18.2 kDa using this approach.

  6. New architecture of fast parallel multiplier using fast parallel counter with FPA (first partial product addition)

    NASA Astrophysics Data System (ADS)

    Lee, Mike M.; Cho, Byung Lok

    2001-11-01

    In this paper, we proposed a new First Partial product Addition (FPA) architecture with new compressor (or parallel counter) to CSA tree built in the process of adding partial product for improving speed in the fast parallel multiplier to improve the speed of calculating partial product by about 20% compared with existing parallel counter using full Adder. The new circuit reduces the CLA bit finding final sum by N/2 using the novel FPA architecture. A 5.14ns of multiplication speed of the 16X16 multiplier is obtained using 0.25um CMOS technology. The architecture of the multiplier is easily opted for pipeline design and demonstrates high speed performance.

  7. Multiply Confined Nickel Nanocatalysts Produced by Atomic Layer Deposition for Hydrogenation Reactions.

    PubMed

    Gao, Zhe; Dong, Mei; Wang, Guizhen; Sheng, Pei; Wu, Zhiwei; Yang, Huimin; Zhang, Bin; Wang, Guofu; Wang, Jianguo; Qin, Yong

    2015-07-27

    To design highly efficient catalysts, new concepts for optimizing the metal-support interactions are desirable. Here we introduce a facile and general template approach assisted by atomic layer deposition (ALD), to fabricate a multiply confined Ni-based nanocatalyst. The Ni nanoparticles are not only confined in Al2 O3 nanotubes, but also embedded in the cavities of Al2 O3 interior wall. The cavities create more Ni-Al2 O3 interfacial sites, which facilitate hydrogenation reactions. The nanotubes inhibit the leaching and detachment of Ni nanoparticles. Compared with the Ni-based catalyst supported on the outer surface of Al2 O3 nanotubes, the multiply confined catalyst shows a striking improvement of catalytic activity and stability in hydrogenation reactions. Our ALD-assisted template method is general and can be extended for other multiply confined nanoreactors, which may have potential applications in many heterogeneous reactions.

  8. Non-cross talk multi-channel photomultiplier using guided electron multipliers

    DOEpatents

    Gomez, J.; Majewski, S.; Weisenberger, A.G.

    1995-09-26

    An improved multi-channel electron multiplier is provided that exhibits zero cross-talk and high rate operation. Resistive material input and output masks are employed to control divergence of electrons. Electron multiplication takes place in closed channels. Several embodiments are provided for these channels including a continuous resistive emissive multiplier and a discrete resistive multiplier with discrete dynode chains interspaced with resistive layers-masks. Both basic embodiments provide high gain multiplication of electrons without accumulating surface charges while containing electrons to their proper channels to eliminate cross-talk. The invention can be for example applied to improve the performance of ion mass spectrometers, positron emission tomography devices, in DNA sequencing and other beta radiography applications and in many applications in particle physics. 28 figs.

  9. Non cross talk multi-channel photomultiplier using guided electron multipliers

    DOEpatents

    Gomez, Javier; Majewski, Stanislaw; Weisenberger, Andrew G.

    1995-01-01

    An improved multi-channel electron multiplier is provided that exhibits zero cross-talk and high rate operation. Resistive material input and output masks are employed to control divergence of electrons. Electron multiplication takes place in closed channels. Several embodiments are provided for these channels including a continuous resistive emissive multiplier and a discrete resistive multiplier with discrete dynode chains interspaced with resistive layers-masks. Both basic embodiments provide high gain multiplication of electrons without accumulating surface charges while containing electrons to their proper channels to eliminate cross-talk. The invention can be for example applied to improve the performance of ion mass spectrometers, positron emission tomography devices, in DNA sequencing and other beta radiography applications and in many applications in particle physics.

  10. A structural analysis of small vapor-deposited 'multiply twinned' gold particles

    NASA Technical Reports Server (NTRS)

    Yang, C. Y.; Heinemann, K.; Yacaman, M. J.; Poppa, H.

    1979-01-01

    High resolution selected zone dark field, Bragg reflection imaging and weak beam dark field techniques of transmission electron microscopy were used to determine the structure of small gold particles vapor deposited on NaCl substrates. Attention was focused on the analysis of those particles in the 50-150 A range that have pentagonal or hexagonal bright field profiles. These particles have been previously described as multiply twinned crystallites composed of face-centered cubic tetrahedra. The experimental evidence of the present studies can be interpreted on the assumption that the particle structure is a regular icosahedron or decahedron for the hexagonal or the pentagonal particles respectively. The icosahedron is a multiply twinned rhombohedral crystal and the decahedron is a multiply twinned body-centered orthorhombic crystal, each of which constitutes a slight distortion from the face-centered cubic structure.

  11. Coherent Raman scattering with incoherent light for a multiply resonant mixture: Theory

    NASA Astrophysics Data System (ADS)

    Kirkwood, Jason C.; Ulness, Darin J.; Stimson, Michael J.; Albrecht, A. C.

    1998-02-01

    The theory for coherent Raman scattering (CRS) with broadband incoherent light is presented for a multiply resonant, multicomponent mixture of molecules that exhibits simultaneous multiple resonances with the frequencies of the driving fields. All possible pairwise hyperpolarizability contributions to the signal intensity are included in the theoretical treatment-(resonant-resonant, resonant-nonresonant, and nonresonant-nonresonant correlations between chromophores) and it is shown how the different types of correlations manifest themselves as differently behaved components of the signal intensity. The Raman resonances are modeled as Lorentzians in the frequency domain, as is the spectral density of the incoherent light. The analytic results for this multiply resonant mixture are presented and applied to a specific binary mixture. These analytic results will be used to recover frequencies and dephasing times in a series of experiments on multiply resonant mixtures.

  12. The formation of molecules in interstellar clouds from singly and multiply ionized atoms

    NASA Technical Reports Server (NTRS)

    Langer, W. D.

    1978-01-01

    The suggestion is considered that multiply ionized atoms produced by K- and L-shell X-ray ionization and cosmic-ray ionization can undergo ion-molecule reactions and also initiate molecule production. The role of X-rays in molecule production in general is discussed, and the contribution to molecule production of the C(+) radiative association with hydrogen is examined. Such gas-phase reactions of singly and multiply ionized atoms are used to calculate molecular abundances of carbon-, nitrogen-, and oxygen-bearing species. The column densities of the molecules are evaluated on the basis of a modified version of previously developed isobaric cloud models. It is found that reactions of multiply ionized carbon with H2 can contribute a significant fraction of the observed CH in diffuse interstellar clouds in the presence of diffuse X-ray structures or discrete X-ray sources and that substantial amounts of CH(+) can be produced under certain conditions.

  13. Schedulling Economical Thermal Power Plant 500 KV Java-Bali System Using Lagrange Multiplier

    NASA Astrophysics Data System (ADS)

    Sartika, N.; Abdullah, A. G.; Hakim, D. L.

    2017-03-01

    The highest cost of electricity generation operation is fuel cost. Therefore, it is necessary to optimize the thermal generator scheduling. The present study aimed at obtaining the schedule and load sharing of the electric power generation, in order to gain the minimum fuel cost, with regard to inequality and equality constraints. The data tested was the thermal generation system of 500 kV Java-Bali using daily loads. This study employed a lagrange multiplier method to perform the economic scheduling. This method is one of mathematical techniques commonly used to solve economic dispatch problems. The results of the optimation of lagrange multiplier were compared with the real condition in the field. Based on the optimation results, it was found that the lagrange multiplier method is more economical than the real condition of system.

  14. Optimal fractionation and bioassay plans for isolation of synergistic chemicals: The subtractive-combination method.

    PubMed

    Byers, J A

    1992-09-01

    Studies of chemical ecology of an organism are founded on the isolation and identification of a semiochemical, often comprised of two or more synergistic compounds (each Synergist alone has little activity, but presented together they are bioactive). Chromatographie fractionation and bioassay methods of binary splitting, additive combination, and subtractive combination are compared for efficiency in isolating synergists. Formulas are derived for the latter two methods that calculate the expected number of bioassay tests required for isolation of from two to five synergists from biological extracts with any number of compounds, depending on the number of initial (major) Chromatographic fractions. A computer program based on the formulas demonstrates the superiority of the subtractive-combination method. Simulations with the program were used to determine the optimal number of initial fractions for the additive- and subtractive-combination methods when isolating two to five synergists from extracts of from 25 to 1200 compounds. Methods of bioassay, isolation, identification, and field testing of semiochemicals are discussed.

  15. Effect of relative nanohole position on colour purity of ultrathin plasmonic subtractive colour filters.

    PubMed

    Sun, L B; Hu, X L; Zeng, Beibei; Wang, L S; Yang, S M; Tai, R Z; Fecht, H J; Zhang, D X; Jiang, J Z

    2015-07-31

    Plasmonic subtractive color filters through patterning periodic nanostructures on ultrathin Ag films deposited on a glass substrate, exhibiting good durability, simple fabrication, and flexible color tunability, have attracted considerable attention due to their tremendous potential applications. While previous studies have mainly focused on their extraordinary physical mechanisms, color purity, which is another key parameter for high quality imaging applications, has been much less investigated. In this work, we demonstrate that the relative position of nanoholes patterned on ultrathin Ag films can largely affect the color purity of plasmonic subtractive color filters. The calculated results agree reasonably well with the experimental data, revealing that the purity of subtractive colors can be improved by changing the nanohole arrays from square lattice to triangular lattice without reducing transmission at visible frequencies. In addition, underlying mechanisms are clarified by systematically analyzing the dominant valley in transmission spectra.

  16. Enhancing quantum entanglement for continuous variables by a coherent superposition of photon subtraction and addition

    SciTech Connect

    Lee, Su-Yong; Kim, Ho-Joon; Ji, Se-Wan; Nha, Hyunchul

    2011-07-15

    We investigate how the entanglement properties of a two-mode state can be improved by performing a coherent superposition operation ta+ra{sup {dagger}} of photon subtraction and addition, proposed by Lee and Nha [Phys. Rev. A 82, 053812 (2010)], on each mode. We show that the degree of entanglement, the Einstein-Podolsky-Rosen-type correlation, and the performance of quantum teleportation can be all enhanced for the output state when the coherent operation is applied to a two-mode squeezed state. The effects of the coherent operation are more prominent than those of the mere photon subtraction a and the addition a{sup {dagger}} particularly in the small-squeezing regime, whereas the optimal operation becomes the photon subtraction (case of r=0) in the large-squeezing regime.

  17. [The backgroud sky subtraction around [OIII] line in LAMOST QSO spectra].

    PubMed

    Shi, Zhi-Xin; Comte, Georges; Luo, A-Li; Tu, Liang-Ping; Zhao, Yong-Heng; Wu, Fu-Chao

    2014-11-01

    At present, most sky-subtraction methods focus on the full spectrum, not the particular location, especially for the backgroud sky around [OIII] line which is very important to low redshift quasars. A new method to precisely subtract sky lines in local region is proposed in the present paper, which sloves the problem that the width of Hβ-[OIII] line is effected by the backgroud sky subtraction. The exprimental results show that, for different redshift quasars, the spectral quality has been significantly improved using our method relative to the original batch program by LAMOST. It provides a complementary solution for the small part of LAMOST spectra which are not well handled by LAMOST 2D pipeline. Meanwhile, This method has been used in searching for candidates of double-peaked Active Galactic Nuclei.

  18. Subtraction-based approach for enhancing the depth sensitivity of time-resolved NIRS

    PubMed Central

    Milej, Daniel; Abdalmalak, Androu; McLachlan, Peter; Diop, Mamadou; Liebert, Adam; St. Lawrence, Keith.

    2016-01-01

    The aim of this study was to evaluate enhancing of the depth sensitivity of time-resolved near-infrared spectroscopy with a subtraction-based approach. Due to the complexity of light propagation in a heterogeneous media, and to prove the validity of the proposed method in a heterogeneous turbid media we conducted a broad analysis taking into account a number of parameters related to the method as well as various parameters of this media. The results of these experiments confirm that the depth sensitivity of the subtraction-based approach is better than classical approaches using continuous-wave or time-resolved methods. Furthermore, the results showed that the subtraction-based approach has a unique, selective sensitivity to a layer at a specific depth. In vivo application of the proposed method resulted in a greater magnitude of the hemodynamic changes during functional activation than with the standard approach. PMID:27895992

  19. The effects of camera jitter for background subtraction algorithms on fused infrared-visible video streams

    NASA Astrophysics Data System (ADS)

    Becker, Stefan; Scherer-Negenborn, Norbert; Thakkar, Pooja; Hübner, Wolfgang; Arens, Michael

    2016-10-01

    This paper is a continuation of the work of Becker et al.1 In their work, they analyzed the robustness of various background subtraction algorithms on fused video streams originating from visible and infrared cameras. In order to cover a broader range of background subtraction applications, we show the effects of fusing infrared-visible video streams from vibrating cameras on a large set of background subtraction algorithms. The effectiveness is quantitatively analyzed on recorded data of a typical outdoor sequence with a fine-grained and accurate annotation of the images. Thereby, we identify approaches which can benefit from fused sensor signals with camera jitter. Finally conclusions on what fusion strategies should be preferred under such conditions are given.

  20. Dependence of multiply charged ions on the polarization state in nanosecond laser-benzene cluster interaction

    NASA Astrophysics Data System (ADS)

    Wang, Weiguo; Zhao, Wuduo; Hua, Lei; Hou, Keyong; Li, Haiyang

    2016-05-01

    This paper investigated the dependence of multiply charged ions on the laser polarization state when benzene cluster was irradiated with 532 and 1064 nm nanosecond laser. A circle, square and flower distribution for C2+, C3+ and C4+ were observed with 532 nm laser respectively, while flower petals for C2+, C3+ and C4+ were observed at 1064 nm as the laser polarization varied. A theoretical calculation was performed to interpret the polarization state and wavelength dependence of the multiply charged ions. The simulated results agreed well with the experimental observation with considering the contribution from the cluster disintegration.

  1. A Schottky/2-DEG varactor diode for millimeter and submillimeter wave multiplier applications

    NASA Technical Reports Server (NTRS)

    Peatman, W. C. B.; Crowe, Thomas W.; Shur, M.; Gelmont, B.

    1992-01-01

    A new Schottky diode is investigated for use as a multiplier element in the millimeter and submillimeter wavelength regions. The new diode is based on the Schottky contact at the edge of a 2-dimensional electron gas (2-DEG). As a negative voltage is applied to the Schottky contact, the depletion layer between the Schottky contact and the 2-DEG expands and the junction capacitance decreases, resulting in a nonlinear capacitance-voltage characteristic. In this paper, we outline the theory, design, fabrication, and evaluation of the new device. Recent results include devices having cutoff frequencies of 1 THz and above. Preliminary multiplier results are also presented.

  2. Design Considerations for Heavily-Doped Cryogenic Schottky Diode Varactor Multipliers

    NASA Technical Reports Server (NTRS)

    Schlecht, E.; Maiwald, F.; Chattopadhyay, G.; Martin, S.; Mehdi, I.

    2001-01-01

    Diode modeling for Schottky varactor frequency multipliers above 500 GHz is presented with special emphasis placed on simple models and fitted equations for rapid circuit design. Temperature- and doping-dependent mobility, resistivity, and avalanche current multiplication and breakdown are presented. Next is a discussion of static junction current, including the effects of tunneling as well as thermionic emission. These results have been compared to detailed measurements made down to 80 K on diodes fabricated at JPL, followed by a discussion of the effect on multiplier efficiency. Finally, a simple model of current saturation in the undepleted active layer suitable for inclusion in harmonic balance simulators is derived.

  3. Theory of a stationary microwave discharge with multiply charged ions in an expanding gas jet

    NASA Astrophysics Data System (ADS)

    Shalashov, A. G.; Abramov, I. S.; Golubev, S. V.; Gospodchikov, E. D.

    2016-08-01

    The formation of a jet of a nonequilibrium multiply charged ion plasma is studied in the inhomogeneous gas jet. It is shown that the geometrical divergence of the jet restricts the maximum ion charge state and results in the spatial localization of the discharge. Stationary solutions corresponding to such regimes are constructed. The model proposed can be used to optimize modern experiments on generation of hard UV radiation due to the line emission of multiply ionized atoms in a gas jet heated by high-power millimeter and submillimeter radiation.

  4. Effect of color coding and subtraction on the accuracy of contrast echocardiography

    NASA Technical Reports Server (NTRS)

    Pasquet, A.; Greenberg, N.; Brunken, R.; Thomas, J. D.; Marwick, T. H.

    1999-01-01

    BACKGROUND: Contrast echocardiography may be used to assess myocardial perfusion. However, gray scale assessment of myocardial contrast echocardiography (MCE) is difficult because of variations in regional backscatter intensity, difficulties in distinguishing varying shades of gray, and artifacts or attenuation. We sought to determine whether the assessment of rest myocardial perfusion by MCE could be improved with subtraction and color coding. METHODS AND RESULTS: MCE was performed in 31 patients with previous myocardial infarction with a 2nd generation agent (NC100100, Nycomed AS), using harmonic triggered or continuous imaging and gain settings were kept constant throughout the study. Digitized images were post processed by subtraction of baseline from contrast data and colorized to reflect the intensity of myocardial contrast. Gray scale MCE alone, MCE images combined with baseline and subtracted colorized images were scored independently using a 16 segment model. The presence and severity of myocardial contrast abnormalities were compared with perfusion defined by rest MIBI-SPECT. Segments that were not visualized by continuous (17%) or triggered imaging (14%) after color processing were excluded from further analysis. The specificity of gray scale MCE alone (56%) or MCE combined with baseline 2D (47%) was significantly enhanced by subtraction and color coding (76%, p<0.001) of triggered images. The accuracy of the gray scale approaches (respectively 52% and 47%) was increased to 70% (p<0.001). Similarly, for continuous images, the specificity of gray scale MCE with and without baseline comparison was 23% and 42% respectively, compared with 60% after post processing (p<0.001). The accuracy of colorized images (59%) was also significantly greater than gray scale MCE (43% and 29%, p<0.001). The sensitivity of MCE for both acquisitions was not altered by subtraction. CONCLUSION: Post-processing with subtraction and color coding significantly improves the accuracy

  5. Modeling self-subtraction in angular differential imaging: Application to the HD 32297 debris disk

    SciTech Connect

    Esposito, Thomas M.; Fitzgerald, Michael P.; Graham, James R.; Kalas, Paul

    2014-01-01

    We present a new technique for forward-modeling self-subtraction of spatially extended emission in observations processed with angular differential imaging (ADI) algorithms. High-contrast direct imaging of circumstellar disks is limited by quasi-static speckle noise, and ADI is commonly used to suppress those speckles. However, the application of ADI can result in self-subtraction of the disk signal due to the disk's finite spatial extent. This signal attenuation varies with radial separation and biases measurements of the disk's surface brightness, thereby compromising inferences regarding the physical processes responsible for the dust distribution. To compensate for this attenuation, we forward model the disk structure and compute the form of the self-subtraction function at each separation. As a proof of concept, we apply our method to 1.6 and 2.2 μm Keck adaptive optics NIRC2 scattered-light observations of the HD 32297 debris disk reduced using a variant of the 'locally optimized combination of images' algorithm. We are able to recover disk surface brightness that was otherwise lost to self-subtraction and produce simplified models of the brightness distribution as it appears with and without self-subtraction. From the latter models, we extract radial profiles for the disk's brightness, width, midplane position, and color that are unbiased by self-subtraction. Our analysis of these measurements indicates a break in the brightness profile power law at r ≈ 110 AU and a disk width that increases with separation from the star. We also verify disk curvature that displaces the midplane by up to 30 AU toward the northwest relative to a straight fiducial midplane.

  6. Intensity Weighted Subtraction Microscopy Approach for Image Contrast and Resolution Enhancement

    PubMed Central

    Korobchevskaya, Kseniya; Peres, Chiara; Li, Zhibin; Antipov, Alexei; Sheppard, Colin J. R.; Diaspro, Alberto; Bianchini, Paolo

    2016-01-01

    We propose and demonstrate a novel subtraction microscopy algorithm, exploiting fluorescence emission difference or switching laser mode and their derivatives for image enhancement. The key novelty of the proposed approach lies in the weighted subtraction coefficient, adjusted pixel-by-pixel with respect to the intensity distributions of initial images. This method produces significant resolution enhancement and minimizes image distortions. Our theoretical and experimental studies demonstrate that this approach can be applied to any optical microscopy techniques, including label free and non-linear methods, where common super-resolution techniques cannot be used. PMID:27174367

  7. Resolution and contrast enhancement of subtractive second harmonic generation microscopy with a circularly polarized vortex beam

    PubMed Central

    Tian, Nian; Fu, Ling; Gu, Min

    2015-01-01

    We extend the subtractive imaging method to label-free second harmonic generation (SHG) microscopy to enhance the spatial resolution and contrast. This method is based on the intensity difference between two images obtained with circularly polarized Gaussian and doughnut-shaped beams, respectively. By characterizing the intensity and polarization distributions of the two focused beams, we verify the feasibility of the subtractive imaging method in polarization dependent SHG microscopy. The resolution and contrast enhancement in different biological samples is demonstrated. This work will open a new avenue for the applications of SHG microscopy in biomedical research. PMID:26364733

  8. Digital subtraction cisternography: a new approach to fistula localisation in cerebrospinal fluid rhinorrhoea.

    PubMed Central

    Byrne, J V; Ingram, C E; MacVicar, D; Sullivan, F M; Uttley, D

    1990-01-01

    Positive contrast cisternography with digital subtraction of fluoroscopy images before computed tomography (CT) was employed in the investigation of eight patients with cerebrospinal fluid (CSF) rhinorrhoea. Fistulae were visualised by preliminary digital subtraction cisternography (DSC) in six patients and in five patients the sites of leakage were confirmed at surgery. Fluoroscopy facilitated interpretation of CT in all the positive studies and in two patients provided information which could not be deduced from CT cisternography (CTC) alone. The combined technique is recommended for the investigation of patients with recurrent and post operative CSF rhinorrhoea and when CTC alone fails to identify the site of leakage. Images PMID:2292701

  9. The Various Challenges of Subtracting Speckles and Planet Detection/Characterization in High Contrast Imaging

    NASA Astrophysics Data System (ADS)

    Marois, Christian

    2015-08-01

    Significant progresses have been achieved over the last 20 years in the field of speckle subtraction and planet detection. From the early days of simple “reference star subtraction”, astronomers are now using more advance observing techniques, such as the SDI and ADI, that are combined with complex image processing algorithms to gain more than two orders of magnitude of contrast. I will review the various observing techniques and algorithms now used in the field, as well as the various challenges when trying to optimize the speckle subtraction to maximize planet detection and characterization. In addition, I will review the difficult problem of identifying faint planets in noisy speckle-limited images.

  10. Intensity Weighted Subtraction Microscopy Approach for Image Contrast and Resolution Enhancement

    NASA Astrophysics Data System (ADS)

    Korobchevskaya, Kseniya; Peres, Chiara; Li, Zhibin; Antipov, Alexei; Sheppard, Colin J. R.; Diaspro, Alberto; Bianchini, Paolo

    2016-05-01

    We propose and demonstrate a novel subtraction microscopy algorithm, exploiting fluorescence emission difference or switching laser mode and their derivatives for image enhancement. The key novelty of the proposed approach lies in the weighted subtraction coefficient, adjusted pixel-by-pixel with respect to the intensity distributions of initial images. This method produces significant resolution enhancement and minimizes image distortions. Our theoretical and experimental studies demonstrate that this approach can be applied to any optical microscopy techniques, including label free and non-linear methods, where common super-resolution techniques cannot be used.

  11. Using a digital signal processor as a data stream controller for digital subtraction angiography

    SciTech Connect

    Meng, J.D.; Katz, J.E.

    1991-10-01

    High speed, flexibility, and good arithmetic abilities make digital signal processors (DSP) a good choice as input/output controllers for real time applications. The DSP can be made to pre-process data in real time to reduce data volume, to open early windows on what is being acquired and to implement local servo loops. We present an example of a DSP as an input/output controller for a digital subtraction angiographic imaging system. The DSP pre-processes the raw data, reducing data volume by a factor of two, and is potentially capable of producing real-time subtracted images for immediate display.

  12. 40 CFR 63.3966 - How do I determine the add-on control device emission destruction or removal efficiency?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 13 2012-07-01 2012-07-01 false How do I determine the add-on control... Emission Rate with Add-on Controls Option § 63.3966 How do I determine the add-on control device emission... the add-on control device emission destruction or removal efficiency as part of the performance...

  13. 40 CFR 63.4566 - How do I determine the add-on control device emission destruction or removal efficiency?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 13 2013-07-01 2012-07-01 true How do I determine the add-on control... with Add-on Controls Option § 63.4566 How do I determine the add-on control device emission destruction... add-on control device emission destruction or removal efficiency as part of the performance...

  14. 40 CFR 63.3966 - How do I determine the add-on control device emission destruction or removal efficiency?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 13 2013-07-01 2012-07-01 true How do I determine the add-on control... Emission Rate with Add-on Controls Option § 63.3966 How do I determine the add-on control device emission... the add-on control device emission destruction or removal efficiency as part of the performance...

  15. 40 CFR 63.4566 - How do I determine the add-on control device emission destruction or removal efficiency?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 13 2014-07-01 2014-07-01 false How do I determine the add-on control... with Add-on Controls Option § 63.4566 How do I determine the add-on control device emission destruction... add-on control device emission destruction or removal efficiency as part of the performance...

  16. 40 CFR 63.4566 - How do I determine the add-on control device emission destruction or removal efficiency?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 13 2012-07-01 2012-07-01 false How do I determine the add-on control... with Add-on Controls Option § 63.4566 How do I determine the add-on control device emission destruction... add-on control device emission destruction or removal efficiency as part of the performance...

  17. 40 CFR 63.3966 - How do I determine the add-on control device emission destruction or removal efficiency?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 13 2014-07-01 2014-07-01 false How do I determine the add-on control... Emission Rate with Add-on Controls Option § 63.3966 How do I determine the add-on control device emission... the add-on control device emission destruction or removal efficiency as part of the performance...

  18. 40 CFR 63.3966 - How do I determine the add-on control device emission destruction or removal efficiency?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 12 2011-07-01 2009-07-01 true How do I determine the add-on control... with Add-on Controls Option § 63.3966 How do I determine the add-on control device emission destruction... add-on control device emission destruction or removal efficiency as part of the performance...

  19. Measuring Narcissism within Add Health: The Development and Validation of a New Scale

    ERIC Educational Resources Information Center

    Davis, Mark S.; Brunell, Amy B.

    2012-01-01

    This study reports the development of a measure of narcissism within the National Longitudinal Study of Adolescent Health (Add Health) data set. In Study 1, items were selected from Wave III to form the Add Health Narcissism Scale (AHNS). These were factor analyzed, yielding a single factor comprised of five subscales. We correlated the AHNS and…

  20. 40 CFR Table 1b to Subpart Dddd of... - Add-on Control Systems Compliance Options

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 13 2013-07-01 2012-07-01 true Add-on Control Systems Compliance Options 1B Table 1B to Subpart DDDD of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Products Pt. 63, Subpt. DDDD, Table 1B Table 1B to Subpart DDDD of Part 63—Add-on Control...

  1. 40 CFR Table 1b to Subpart Dddd of... - Add-on Control Systems Compliance Options

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 13 2014-07-01 2014-07-01 false Add-on Control Systems Compliance Options 1B Table 1B to Subpart DDDD of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Products Pt. 63, Subpt. DDDD, Table 1B Table 1B to Subpart DDDD of Part 63—Add-on Control...

  2. Cognitive Control and Attentional Selection in Adolescents with ADHD versus ADD

    ERIC Educational Resources Information Center

    Carr, Laurie; Henderson, John; Nigg, Joel T.

    2010-01-01

    An important research question is whether Attention Deficit Hyperactivity Disorder (ADHD) is related to early- or late-stage attentional control mechanisms and whether this differentiates a nonhyperactive subtype (ADD). This question was addressed in a sample of 145 ADD/ADHD and typically developing comparison adolescents (aged 13-17). Attentional…

  3. 75 FR 73075 - Notice of Motion To Add Exhibit to Petition for Declaratory Order and Complaint

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-29

    ... Energy Regulatory Commission Notice of Motion To Add Exhibit to Petition for Declaratory Order and... of Pella, Iowa (Complainant) filed a motion to add a document as Exhibit P-28 to its July 2, 2010... document is added to a subscribed docket(s). For assistance with any FERC Online service, please...

  4. 40 CFR Table 1b to Subpart Dddd of... - Add-on Control Systems Compliance Options

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 13 2012-07-01 2012-07-01 false Add-on Control Systems Compliance Options 1B Table 1B to Subpart DDDD of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Products Pt. 63, Subpt. DDDD, Table 1B Table 1B to Subpart DDDD of Part 63—Add-on Control...

  5. 7 CFR 360.500 - Petitions to add a taxon to the noxious weed list.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 5 2013-01-01 2013-01-01 false Petitions to add a taxon to the noxious weed list. 360... to add a taxon to the noxious weed list. A person may petition the Administrator to have a taxon added to the noxious weeds lists in § 360.200. Details of the petitioning process for adding a taxon...

  6. Right Hemisphere Deficit Syndrome: Similarities with Subtypes of Children with Attention Deficit Disorder (ADD).

    ERIC Educational Resources Information Center

    Matazow, Gail S.; Hynd, George W.

    Children with Attention Deficit Disorder (ADD) often exhibit problems in visual spatial perception, math achievement, and social skills, and it has been postulated that this constellation of behaviors may constitute Right Hemisphere Deficit Syndrome (RHDS). This study examined 21 children with attention deficit disorder with hyperactivity (ADD/H),…

  7. 40 CFR Table 1b to Subpart Dddd of... - Add-on Control Systems Compliance Options

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 12 2011-07-01 2009-07-01 true Add-on Control Systems Compliance.... 63, Subpt. DDDD, Table 1B Table 1B to Subpart DDDD of Part 63—Add-on Control Systems Compliance... compliance options by using an emissions control system . . . Fiberboard mat dryer heated zones (at...

  8. Power Parenting for Children with ADD/ADHD: A Practical Parent's Guide for Managing Difficult Behaviors.

    ERIC Educational Resources Information Center

    Flick, Grad L.

    The first step in dealing with an attention deficit disorder (ADD/ADHD) child's difficult behavior is to understand its origins. This book presents behavior management techniques to help parents care for their ADD child while ensuring that the child continues to develop positive, healthy self-esteem. The guide shows how to: (1) ensure an accurate…

  9. Prevalence of Aggression and Defiance in Children with ADD/ADHD Tendencies

    ERIC Educational Resources Information Center

    Hill, Janella

    2011-01-01

    Attention Deficit Disorder (ADD) and Attention Deficit Hyperactivity Disorder (ADHD) appear to have become more prevalent in the past few years. Many children who display ADD/ADHD tendencies also display behaviors which cause problems in a classroom setting. Considering the fact that these behaviors could be displayed by the student population as…

  10. 20 Ways To...Collaborate with Families of Children with ADD.

    ERIC Educational Resources Information Center

    Mathur, Smita; Smith, Robin M.

    2003-01-01

    Twenty ideas for collaborating with families of children with attention deficit disorder (ADD) include: (1) providing information about ADD to families; (2) planning meetings to accommodate family members; (3) addressing the language needs of families; (4) helping family members develop their advocacy skills; and (5) helping families network with…

  11. It All ADDs Up: Help for Children with Attention Deficit Disorders.

    ERIC Educational Resources Information Center

    Anderson, Marilyn

    2000-01-01

    Suggestions for working with students with attention deficit disorders (ADD) include: seek medical evaluation; discuss treatment options with the physician and school; communicate with the child's teachers; provide feedback, praise, and consequences; help the child develop social skills; understand when ADD with hyperactivity is disabling; know…

  12. Test Review: Brown Attention-Deficit Disorder Scales and Brown ADD Diagnostic Forms.

    ERIC Educational Resources Information Center

    Muniz, Linda

    1996-01-01

    This article on the Brown Attention-Deficit Disorder (ADD) Scale for Adolescents and the Brown ADD Scale for Adults describes the tests' recommended uses, administration, components, standardization, reliability, and validity. The self-report measures are designed for initial screening, as one part of a comprehensive diagnostic assessment, and for…

  13. 12 CFR Appendix A to Subpart A of... - Method to Derive Pricing Multipliers and Uniform Amount

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Uniform Amount A Appendix A to Subpart A of Part 327 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION REGULATIONS AND STATEMENTS OF GENERAL POLICY ASSESSMENTS In General Pt. 327, Subpt. A, App. A Appendix A to Subpart A of Part 327—Method to Derive Pricing Multipliers and Uniform Amount I....

  14. 12 CFR Appendix A to Subpart A of... - Method to Derive Pricing Multipliers and Uniform Amount

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Uniform Amount A Appendix A to Subpart A of Part 327 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION REGULATIONS AND STATEMENTS OF GENERAL POLICY ASSESSMENTS In General Pt. 327, Subpt. A, App. A Appendix A to Subpart A of Part 327—Method to Derive Pricing Multipliers and Uniform Amount I....

  15. 12 CFR Appendix A to Subpart A of... - Method to Derive Pricing Multipliers and Uniform Amount

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Uniform Amount A Appendix A to Subpart A of Part 327 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION REGULATIONS AND STATEMENTS OF GENERAL POLICY ASSESSMENTS In General Pt. 327, Subpt. A, App. A Appendix A to Subpart A of Part 327—Method to Derive Pricing Multipliers and Uniform Amount I....

  16. Teaching multiply controlled intraverbals to children and adolescents with autism spectrum disorders.

    PubMed

    Kisamore, April N; Karsten, Amanda M; Mann, Charlotte C

    2016-12-01

    Reciprocal conversations, instructional activities, and other social interactions are replete with multiply controlled intraverbals, examples of which have been conceptualized in terms of conditional discriminations. Although the acquisition of conditional discriminations has been examined extensively in the behavior-analytic literature, little research has evaluated procedures to establish multiply controlled intraverbals. Thus, the purpose of this investigation was to evaluate the effects of procedures based on conditional discrimination training on the acquisition of multiply controlled intraverbals with 7 participants who had been diagnosed with autism spectrum disorders. We evaluated the effects of prompt delay with error correction, a differential observing response (DOR), and a DOR plus blocked trials on the acquisition of intraverbals using a multiple baseline design. Accuracy of intraverbal performance increased for at least 1 set of stimuli for all participants under prompt delay with error correction conditions; however, 4 participants required additional teaching (i.e., DOR, modified DOR, modified prompt delay with error correction). Based on these findings, when prompt delay with error correction is not sufficient to establish multiply controlled intraverbals, prompted DORs may be an effective alternative.

  17. Low-voltage harmonic multiplying gyrotron traveling-wave amplifier in G band

    SciTech Connect

    Yeh, Y. S.; Guo, Y. W.; Kao, B. H.; Chen, C. H.; Wang, Z. W.; Hung, C. L.; Chang, T. H.

    2015-12-15

    Harmonic multiplying operation in a gyrotron traveling-wave amplifier (gyro-TWA) permits for magnetic field reduction and frequency multiplication. Lowering a beam voltage is an important step toward miniaturization of a harmonic multiplying gyro-TWA. However, the additional degree of freedom that is provided by the multitude cyclotron harmonics in a low-voltage harmonic multiplying gyro-TWA still easily generates various competing modes. An improved mode-selective circuit, using circular waveguides with various radii, can provide the rejection points within the frequency range to suppress competing modes. Simulated results reveal that the mode-selective circuit can provide an attenuation of more than 14 dB to suppress the competing modes. Furthermore, the performance of the gyro-TWA is analyzed for studying the sensitivity of the saturated output power and full width at half maximum bandwidth of the gyro-TWA to the beam voltage and the magnetic field. A stable low-voltage harmonic multiplying gyro-TWA with the mode-selective circuit is predicted to yield a peak output power of 24 kW at 200.4 GHz, corresponding to a saturated gain of 56 dB at an interaction efficiency of 20%. The full width at half maximum bandwidth is 3.0 GHz.

  18. Regulation of a lightweight high efficiency capacitator diode voltage multiplier dc-dc converter

    NASA Technical Reports Server (NTRS)

    Harrigill, W. T., Jr.; Myers, I. T.

    1976-01-01

    A method for the regulation of a capacitor diode voltage multiplier dc-dc converter has been developed which has only minor penalties in weight and efficiency. An auxiliary inductor is used, which only handles a fraction of the total power, to control the output voltage through a pulse width modulation method in a buck boost circuit.

  19. Regulation of a lightweight high efficiency capacitor diode voltage multiplier dc-dc converter

    NASA Technical Reports Server (NTRS)

    Harrigill, W. T., Jr.; Myers, I. T.

    1976-01-01

    A method for the regulation of a capacitor diode voltage multiplier dc-dc converter has been developed which has only minor penalties in weight and efficiency. An auxiliary inductor is used, which only handles a fraction of the total power, to control the output voltage through a pulse width modulation method in a buck boost circuit.

  20. Training Pragmatic Language Skills through Alternate Strategies with a Blind Multiply Handicapped Child.

    ERIC Educational Resources Information Center

    Evans, C. J.; Johnson, C. J.

    1988-01-01

    A blind multiply handicapped preschooler was taught to respond appropriately to two adjacency pair types ("where question-answer" and "comment-acknowledgement"). The two alternative language acquisition strategies available to blind children were encouraged: echolalia to maintain communicative interactions and manual searching…

  1. Harmonic balance optimization of terahertz Schottky diode multipliers using an advanced device model

    NASA Technical Reports Server (NTRS)

    Schlecht, E. T.; Chattopadhyay, G.; Maestrini, A.; Pukala, D.; Gill, J.; Mehdi, I.

    2002-01-01

    Substantial proress has been made recently in the advancement of solid state terahertz sources using chains of Schottky diode frequency multipliers. We have developed a harmonic balance simulator and corresponding diode model that incorporates many other factors participating in the diode behavior.

  2. Focus on the Hands: A Beginning Approach to Teaching Typing to Visually Impaired, Multiply Handicapped Students.

    ERIC Educational Resources Information Center

    Dibble, Frances J. Bauer

    1984-01-01

    The author describes the value to visually impaired and multiply handicapped students of a good typewriting curriculum. She discusses hand and finger exercises and notes benefits to students from focusing on the hands as well as on the rudiments and total communicative value of typing. (CL)

  3. Cryogenic operation of GaAs based multiplier chains to 400 GHz

    NASA Technical Reports Server (NTRS)

    Maestrini, A.; Pukala, D.; Maiwald, F.; Schlecht, E.; Chattopadhyay, G.; Mehdi, I.

    2000-01-01

    The FIRST/HIFI mission allows for the local oscillator frequency multiplier chains to be cooled to 120 - 150 K in order to increase available output power. This paper will discuss the implication of cooling on GaAs based planar Schottky diode varactors for flight applications.

  4. Teaching Multiply Controlled Intraverbals to Children and Adolescents with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Kisamore, April N.; Karsten, Amanda M.; Mann, Charlotte C.

    2016-01-01

    Reciprocal conversations, instructional activities, and other social interactions are replete with multiply controlled intraverbals, examples of which have been conceptualized in terms of conditional discriminations. Although the acquisition of conditional discriminations has been examined extensively in the behavior-analytic literature, little…

  5. Highly enriched multiply-labeled stable isotopic compounds as atmospheric tracers

    DOEpatents

    Goldblatt, M.; McInteer, B.B.

    1974-01-29

    Compounds multiply-labeled with stable isotopes and highly enriched in these isotopes are readily capable of detection in tracer experiments involving high dilutions. Thus, for example, /sup 13/C/sup 18/O/sub 2/ provides a useful tracer for following atmospheric pol lution produced as a result of fossil fuel burning. (Official Gazette)

  6. A Manual for Assessment and Training of Severely Multiply Handicapped Deaf-Blind Students.

    ERIC Educational Resources Information Center

    Burton, Rosemarie A.; And Others

    Intended for teacher use, the manual provides for the assessment and training of severely multiply handicapped deaf-blind students with sections on self help, motor development, and sensory stimulation training. Included for each skill are an individual rating scale for periodic assessments, a task analysis, and an actual teaching procedure. Found…

  7. Structure of High-Speed Modulo Multiplier Suitable for Repeated Operations

    NASA Astrophysics Data System (ADS)

    Kudou, Tadamichi; Tsunekawa, Yoshitaka; Suzuki, Masayuki

    In this paper, we propose a new modulo multiplier suitable for repeated operations using redundant representations. First, we consider a computation rule for radix-2 modulo multiplications. In radix-2 operation, we show two methods to calculate (2i-1 mod n) from (2i mod n) and decide product digits sequentially from upper side. These methods make it possible to perform (2i-1 mod n) and multiplications simultaneously. Second, we attempt to apply these methods to radix-4 operations which enables us to reduce clock cycles by only shift and sign change. We propose some structures to perform each part efficiently for radix-4 modulo multiplications. The high-speed redundant binary adder/subtractor which we have already proposed is applied to these structures. By using this adder/subtractor, the longest delay path of this modulo multiplier becomes very short. Finally, by using PARTHENON which is a design system for VLSI, this modulo multiplier is designed and evaluated. As a result, we show the speed of this proposed modulo multiplier becomes over 2.5 times as compared with the conventional structures.

  8. Low-voltage harmonic multiplying gyrotron traveling-wave amplifier in G band

    NASA Astrophysics Data System (ADS)

    Yeh, Y. S.; Hung, C. L.; Chang, T. H.; Guo, Y. W.; Kao, B. H.; Chen, C. H.; Wang, Z. W.

    2015-12-01

    Harmonic multiplying operation in a gyrotron traveling-wave amplifier (gyro-TWA) permits for magnetic field reduction and frequency multiplication. Lowering a beam voltage is an important step toward miniaturization of a harmonic multiplying gyro-TWA. However, the additional degree of freedom that is provided by the multitude cyclotron harmonics in a low-voltage harmonic multiplying gyro-TWA still easily generates various competing modes. An improved mode-selective circuit, using circular waveguides with various radii, can provide the rejection points within the frequency range to suppress competing modes. Simulated results reveal that the mode-selective circuit can provide an attenuation of more than 14 dB to suppress the competing modes. Furthermore, the performance of the gyro-TWA is analyzed for studying the sensitivity of the saturated output power and full width at half maximum bandwidth of the gyro-TWA to the beam voltage and the magnetic field. A stable low-voltage harmonic multiplying gyro-TWA with the mode-selective circuit is predicted to yield a peak output power of 24 kW at 200.4 GHz, corresponding to a saturated gain of 56 dB at an interaction efficiency of 20%. The full width at half maximum bandwidth is 3.0 GHz.

  9. Identifying Current and Relevant Curricular Sequences for Multiply Involved Hearing-Impaired Learners.

    ERIC Educational Resources Information Center

    Schloss, Patrick J.

    1984-01-01

    The article provides guidelines for developing curriculum objectives for multiply involved hearing-impaired students. Emphasis is placed on procedures for establishing instructional priorities, assessing the learner against these priorities, selecting and using prosthetics to overcome learning and behavioral deficits, providing educational…

  10. Treatment of Multiply Controlled Problem Behavior with Procedural Variations of Differential Reinforcement

    ERIC Educational Resources Information Center

    Neidert, Pamela L.; Iwata, Brian A.; Dozier, Claudia L.

    2005-01-01

    We describe the assessment and treatment of 2 children with autism spectrum disorder whose problem behaviors (self-injury, aggression, and disruption) were multiply controlled. Results of functional analyses indicated that the children's problem behaviors were maintained by both positive reinforcement (attention) and negative reinforcement (escape…

  11. Wolbachia MLST marker diversity from multiply infected northern corn rootworm (Diabrotica barberi) populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The northern corn rootworm (NCR, Diabrotica barberi) in eastern and central North America exhibits at least three distinct populations with respect to Wolbachia infection: uninfected; singly infected; multiply infected. The infected states are associated with different mtDNA haplotypes and reduced m...

  12. Derivation of a tangent function using an integrated circuit four-quadrant multiplier

    NASA Technical Reports Server (NTRS)

    Bregman, B. J. (Inventor)

    1973-01-01

    A tangent function generator is provided which utilizes input signals proportionate to the sine and cosine of a given angle. The equipment accomplishes a trigonometric manipulation which forms an output signal substantially independent of the input reference voltage but proportional to the tangent of the angle. The device uses a multiplier and operational amplifier.

  13. An Exploration of Social Media Use among Multiply Minoritized LGBTQ Youth

    ERIC Educational Resources Information Center

    Lucero, Alfie Leanna

    2013-01-01

    This study responds to a need for research in a fast-growing and significant area of study, that of exploring, understanding, and documenting the numerous ways that multiply marginalized LGBTQ youth between the ages of 14 and 17 use social media. The primary research question examined whether social media provide safe spaces for multiply…

  14. An Ego-Strengthening Approach with Multiply Traumatized Children: Special Reference to the Sexually Abused

    ERIC Educational Resources Information Center

    Crenshaw, David A.; Mordock, John B.

    2004-01-01

    Seven basic tasks are presented that must be accomplished for successful residential treatment of multiply abused children, and methods are described to achieve each task. The tasks are: empowering the children, respecting their need for privacy, helping them to feel safe and creating "safety nets" for them, building and supporting their defenses,…

  15. A novel four-quadrant analog multiplier using SOI four-gate transitors (G4-FETs)

    NASA Technical Reports Server (NTRS)

    Akarvardar, K.; Chen, S.; Blalock, B. J.; Cristoloveanu, S.; Gentil, P.; Mojarradi, M.

    2005-01-01

    A novel analog muliplier using SOI four-gate transistors (G4-FETs) is presented. Thanks to the multiple inputs of the G4-FET that may be biased independently, the number of transistors in the proposed circuit is dramatically reduced, compared to conventional single-gate MOSFET based multipliers.

  16. Effective CPD on a Large Scale: Examining the Development of Multipliers

    ERIC Educational Resources Information Center

    Roesken-Winter, Bettina; Schüler, Sven; Stahnke, Rebekka; Blömeke, Sigrid

    2015-01-01

    Much research has been conducted on exploring teacher learning and constituting Continuous Professional Development (CPD) designs for teachers. Yet, little is known about appropriate design principles of CPD for teacher trainers/multipliers who in turn are supposed to provide CPD for teachers. The German Center for Mathematics Teacher Education…

  17. MCMC2 (version 1.1.1): A Monte Carlo code for multiply charged clusters

    NASA Astrophysics Data System (ADS)

    Bonhommeau, David A.

    2015-11-01

    This new version of the MCMC2 program for modeling the thermodynamic and structural properties of multiply-charged clusters fixes some minor bugs present in earlier versions. A figure representing the required RAM per replica as a function of the cluster size (N ≤ 20000) is also provided as benchmark.

  18. Radio Telescopes Will Add to Cassini-Huygens Discoveries

    NASA Astrophysics Data System (ADS)

    2004-12-01

    When the European Space Agency's Huygens spacecraft makes its plunge into the atmosphere of Saturn's moon Titan on January 14, radio telescopes of the National Science Foundation's National Radio Astronomy Observatory (NRAO) will help international teams of scientists extract the maximum possible amount of irreplaceable information from an experiment unique in human history. Huygens is the 700-pound probe that has accompanied the larger Cassini spacecraft on a mission to thoroughly explore Saturn, its rings and its numerous moons. The Green Bank Telescope The Robert C. Byrd Green Bank Telescope CREDIT: NRAO/AUI/NSF (Click on image for GBT gallery) The Robert C. Byrd Green Bank Telescope (GBT) in West Virginia and eight of the ten telescopes of the continent-wide Very Long Baseline Array (VLBA), located at Pie Town and Los Alamos, NM, Fort Davis, TX, North Liberty, IA, Kitt Peak, AZ, Brewster, WA, Owens Valley, CA, and Mauna Kea, HI, will directly receive the faint signal from Huygens during its descent. Along with other radio telescopes in Australia, Japan, and China, the NRAO facilities will add significantly to the information about Titan and its atmosphere that will be gained from the Huygens mission. A European-led team will use the radio telescopes to make extremely precise measurements of the probe's position during its descent, while a U.S.-led team will concentrate on gathering measurements of the probe's descent speed and the direction of its motion. The radio-telescope measurements will provide data vital to gaining a full understanding of the winds that Huygens encounters in Titan's atmosphere. Currently, scientists know little about Titan's winds. Data from the Voyager I spacecraft's 1980 flyby indicated that east-west winds may reach 225 mph or more. North-south winds and possible vertical winds, while probably much weaker, may still be significant. There are competing theoretical models of Titan's winds, and the overall picture is best summarized as

  19. Operational Momentum in Large-Number Addition and Subtraction by 9-Month-Olds

    ERIC Educational Resources Information Center

    McCrink, Koleen; Wynn, Karen

    2009-01-01

    Recent studies on nonsymbolic arithmetic have illustrated that under conditions that prevent exact calculation, adults display a systematic tendency to overestimate the answers to addition problems and underestimate the answers to subtraction problems. It has been suggested that this "operational momentum" results from exposure to a…

  20. Generating Scenarios of Addition and Subtraction: A Study of Japanese University Students

    ERIC Educational Resources Information Center

    Kinda, Shigehiro

    2013-01-01

    Students are presented with problems involving three scenario types of addition and subtraction in elementary mathematics: one dynamic ("Change") and two static ("Combine, Compare"). Previous studies have indicated that the dynamic type is easier for school children, whereas the static types are more difficult and comprehended only gradually…

  1. A Cognitive Tool for Teaching the Addition/Subtraction of Common Fractions: A Model of Affordances

    ERIC Educational Resources Information Center

    Kong, Siu Cheung; Kwok, Lam For

    2005-01-01

    The aim of this research is to devise a cognitive tool for meeting the diverse needs of learners for comprehending new procedural knowledge. A model of affordances on teaching fraction equivalence for developing procedural knowledge for adding/subtracting fractions with unlike denominators was derived from the results of a case study of an initial…

  2. Fostering Taiwanese Preschoolers' Understanding of the Addition-Subtraction Inverse Principle

    ERIC Educational Resources Information Center

    Lai, Meng-Lung; Baroody, Arthur J.; Johnson, Amanda R.

    2008-01-01

    The present research involved gauging preschoolers' learning potential for a key arithmetic concept, the addition-subtraction inverse principle (e.g., 2+1-1=2). Sixty 4- and 5-year-old Taiwanese children from two public preschools serving low- and middle-income families participated in the training experiment. Half were randomly assigned to an…

  3. Performance on Addition and Subtraction Problems: Results from Individual Interviews - Sandy Bay Study.

    ERIC Educational Resources Information Center

    Romberg, Thomas A.; And Others

    The purpose of this study was to relate children's cognitive processing capabilities and their grade level to their performance and to the strategies they used when working addition and subtraction problems. From two sets of data which assessed memory capacity and cognitive processing capacities, six groups of children with different cognitive…

  4. Helping Students to Connect Subtraction Strategies Improves Mathematical Reasoning for Students and Teachers

    ERIC Educational Resources Information Center

    Sci, Eve

    2011-01-01

    After administering an end of unit assessment written by the school's math program, teachers of three second grade classes in a New York City school noticed a majority of the students had not demonstrated mastery of subtracting two, two-digit numbers. The teachers worked with the school's math coach to implement an instructional unit that required…

  5. Considering ERP difference scores as individual difference measures: Issues with subtraction and alternative approaches.

    PubMed

    Meyer, Alexandria; Lerner, Matthew D; De Los Reyes, Andres; Laird, Robert D; Hajcak, Greg

    2017-01-01

    There is growing interest in psychophysiological and neural correlates of psychopathology, personality, and other individual differences. Many studies correlate a criterion individual difference variable (e.g., anxiety) with a psychophysiological measurement derived by subtracting scores taken from two within-subject conditions. These subtraction-based difference scores are intended to increase specificity by isolating variability of interest. Using data on the error-related negativity (ERN) and correct response negativity (CRN) in relation to generalized anxiety disorder (GAD), we highlight several conceptual and practical issues with subtraction-based difference scores and propose alternative approaches based on regression. We show that ERN and CRN are highly correlated, and that the ΔERN (i.e., ERN - CRN) is correlated in opposite directions both with ERN and CRN. Bivariate analyses indicate that GAD is related to ΔERN and ERN, but not CRN. We first show that, by using residualized scores, GAD relates both to a larger ERN and smaller CRN. Moreover, by probing the interaction of ERN and CRN, we show that the relationship between GAD and ERN varies by CRN. These latter findings are not evident when using traditional subtraction-based difference scores. We then completed follow-up analyses that suggested that an increased P300 in anxious individuals gave rise to the apparent anxiety/CRN relationship observed. These findings have important conceptual implications for facilitating the interpretability of results from individual difference studies of psychophysiology.

  6. [The improved design of table operating box of digital subtraction angiography device].

    PubMed

    Qi, Xianying; Zhang, Minghai; Han, Fengtan; Tang, Feng; He, Lemin

    2009-12-01

    In this paper are analyzed the disadvantages of CGO-3000 digital subtraction angiography table Operating Box. The authors put forward a communication control scheme between single-chip microcomputer(SCM) and programmable logic controller(PLC). The details of hardware and software of communication are given.

  7. Videodensitometric ejection fraction from intravenous digital subtraction right ventriculograms: correlation with first pass radionuclide ejection fraction

    SciTech Connect

    Detrano, R.; MacIntyre, W.; Salcedo, E.E.; O'Donnell, J.; Underwood, D.A.; Simpfendorfer, C.; Go, R.T.; Butters, K.; Withrow, S.

    1985-06-01

    Thirty-one consecutive patients undergoing intravenous blurred mask digital subtraction right ventriculography were submitted to first pass radionuclide angiography. Second order mask resubtraction of end-diastolic and end-systolic right ventricular digital image frames was executed using preinjection end-diastolic and end-systolic frames to rid the digital subtraction images of mis-registration artifact. End-diastolic and end-systolic perimeters were drawn manually by two independent observers with a light pen. Ejection fractions calculated from the integrated videodensitometric counts within these perimeters correlated well with those derived from the first pass radionuclide right ventriculogram (r = 0.84) and the interobserver correlation was acceptable (r = 0.91). Interobserver differences occurred more frequently in patients with atrial fibrillation and in those whose tricuspid valve planes were difficult to discern on the digital subtraction right ventriculograms. These results suggest that videodensitometric analysis of digital subtraction right ventriculograms is an accurate method of determining right ventricular ejection fraction and may find wide clinical applicability.

  8. [Development of a digital chest phantom for studies on energy subtraction techniques].

    PubMed

    Hayashi, Norio; Taniguchi, Anna; Noto, Kimiya; Shimosegawa, Masayuki; Ogura, Toshihiro; Doi, Kunio

    2014-03-01

    Digital chest phantoms continue to play a significant role in optimizing imaging parameters for chest X-ray examinations. The purpose of this study was to develop a digital chest phantom for studies on energy subtraction techniques under ideal conditions without image noise. Computed tomography (CT) images from the LIDC (Lung Image Database Consortium) were employed to develop a digital chest phantom. The method consisted of the following four steps: 1) segmentation of the lung and bone regions on CT images; 2) creation of simulated nodules; 3) transformation to attenuation coefficient maps from the segmented images; and 4) projection from attenuation coefficient maps. To evaluate the usefulness of digital chest phantoms, we determined the contrast of the simulated nodules in projection images of the digital chest phantom using high and low X-ray energies, soft tissue images obtained by energy subtraction, and "gold standard" images of the soft tissues. Using our method, the lung and bone regions were segmented on the original CT images. The contrast of simulated nodules in soft tissue images obtained by energy subtraction closely matched that obtained using the gold standard images. We thus conclude that it is possible to carry out simulation studies based on energy subtraction techniques using the created digital chest phantoms. Our method is potentially useful for performing simulation studies for optimizing the imaging parameters in chest X-ray examinations.

  9. "It is Possible to Die Before Being Born". Negative Integers Subtraction: A Case Study

    ERIC Educational Resources Information Center

    Gallardo, Aurora

    2003-01-01

    A Case Study is presented in this article, where there is a contradiction between pre-algebraic language semantic and syntax used to solve word problems through a negative integers subtraction. Appendix includes answer key. (Contains 1 figure.) [For complete proceedings, see ED500859.

  10. Addition Table of Colours: Additive and Subtractive Mixtures Described Using a Single Reasoning Model

    ERIC Educational Resources Information Center

    Mota, A. R.; Lopes dos Santos, J. M. B.

    2014-01-01

    Students' misconceptions concerning colour phenomena and the apparent complexity of the underlying concepts--due to the different domains of knowledge involved--make its teaching very difficult. We have developed and tested a teaching device, the addition table of colours (ATC), that encompasses additive and subtractive mixtures in a single…

  11. Brief Report: Additive and Subtractive Counterfactual Reasoning of Children with High-Functioning Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Begeer, Sander; Terwogt, Mark Meerum; Lunenburg, Patty; Stegge, Hedy

    2009-01-01

    The development of additive ("If only I had done...") and subtractive ("If only I had not done....") counterfactual reasoning was examined in children with High Functioning Autism Spectrum Disorders (HFASD) (n = 72) and typically developing controls (n = 71), aged 6-12 years. Children were presented four stories where they could generate…

  12. Spectral Dark Subtraction: A MODTRAN-Based Algorithm for Estimating Ground Reflectance without Atmospheric Information

    NASA Technical Reports Server (NTRS)

    Freedman, Ellis; Ryan, Robert; Pagnutti, Mary; Holekamp, Kara; Gasser, Gerald; Carver, David; Greer, Randy

    2007-01-01

    Spectral Dark Subtraction (SDS) provides good ground reflectance estimates across a variety of atmospheric conditions with no knowledge of those conditions. The algorithm may be sensitive to errors from stray light, calibration, and excessive haze/water vapor. SDS seems to provide better estimates than traditional algorithms using on-site atmospheric measurements much of the time.

  13. cDNA amplification by SMART-PCR and suppression subtractive hybridization (SSH)-PCR.

    PubMed

    Hillmann, Andrew; Dunne, Eimear; Kenny, Dermot

    2009-01-01

    The comparison of two RNA populations that differ from the effects of a single-independent variable, such as a drug treatment or a specific genetic defect, can identify differences in the abundance of specific transcripts that vary in a population-dependent manner. There are a variety of methods for identifying differentially expressed genes, including microarray, SAGE, qRT-PCR, and DDGE. This protocol describes a potentially less sensitive yet relatively easy and cost-effective alternative that does not require prior knowledge of the transcriptomes under investigation and is particularly applicable when minimal levels of starting material, RNA, are available. RNA input can often be a limiting factor when analyzing RNA from, for example, rigorously purified blood cells. This protocol describes the use of SMART-PCR to amplify cDNA from sub-microgram levels of RNA. The amplified cDNA populations under comparison are then subjected to suppression subtractive hybridization (SSH-PCR), a technique that couples subtractive hybridization with suppression PCR to selectively amplify fragments of differentially expressed genes. The final products are cDNA populations enriched for significantly over-represented transcripts in either of the two input RNA preparations. These cDNA populations may then be cloned to make subtracted cDNA libraries and/or used as probes to screen subtracted cDNA, global cDNA, or genomic DNA libraries.

  14. Detecting small anatomical change with 3D serial MR subtraction images

    NASA Astrophysics Data System (ADS)

    Holden, Mark; Denton, Erica R. E.; Jarosz, J. M.; Cox, T. C.; Studholme, Colin; Hawkes, David J.; Hill, Derek L.

    1999-05-01

    Spoiled gradient echo volume MR scans were obtained from 5 growth hormone (GH) patients and 6 normal controls. The patients were scanned before treatment and after 3 and 6 months of GH therapy. The controls were scanned at similar intervals. A calibration phantom was scanned on the same day as each subject. The phantom images were registered with a 9 degree of freedom algorithm to measure scaling errors due to changes in scanner calibration. The second and third images were each registered with a 6 degree of freedom algorithm to the first (baseline) image by maximizing normalized mutual information, and transformed, with and without scaling error correction, using sinc interpolation. Each registered and transformed image had the baseline image subtracted to generate a difference image. Two neuro-radiologists were trained to detect structural change with difference images containing synthetic misregistration and scale changes. They carried out a blinded assessment of anatomical change for the unregistered; aligned and subtracted; and scale corrected, aligned and subtracted images. The results show a significant improvement in the detection of structural change and inter-observer agreement when aligned and subtracted images were used instead of unregistered ones. The structural change corresponded to an increase in brain: CSF ratio.

  15. Preschoolers' Nonsymbolic Arithmetic with Large Sets: Is Addition More Accurate than Subtraction?

    ERIC Educational Resources Information Center

    Shinskey, Jeanne L.; Chan, Cindy Ho-man; Coleman, Rhea; Moxom, Lauren; Yamamoto, Eri

    2009-01-01

    Adult and developing humans share with other animals analog magnitude representations of number that support nonsymbolic arithmetic with large sets. This experiment tested the hypothesis that such representations may be more accurate for addition than for subtraction in children as young as 3 1/2 years of age. In these tasks, the experimenter hid…

  16. Dissociation of Subtraction and Multiplication in the Right Parietal Cortex: Evidence from Intraoperative Cortical Electrostimulation

    ERIC Educational Resources Information Center

    Yu, Xiaodan; Chen, Chuansheng; Pu, Song; Wu, Chenxing; Li, Yongnian; Jiang, Tao; Zhou, Xinlin

    2011-01-01

    Previous research has consistently shown that the left parietal cortex is critical for numerical processing, but the role of the right parietal lobe has been much less clear. This study used the intraoperative cortical electrical stimulation approach to investigate neural dissociation in the right parietal cortex for subtraction and…

  17. Developing Prospective Teachers' Understanding of Addition and Subtraction with Whole Numbers

    ERIC Educational Resources Information Center

    Roy, George J.

    2014-01-01

    This study was situated in a semester-long classroom teaching experiment examining prospective teachers' understanding of number concepts and operations. The purpose of this paper is to describe the learning goals, tasks, and tools used to cultivate prospective teachers' understanding of addition and subtraction with whole numbers. Research…

  18. Identification of a pheA gene associated with Streptococcus mitis by using suppression subtractive hybridization.

    PubMed

    Park, Hee Kuk; Dang, Hien Thanh; Myung, Soon Chul; Kim, Wonyong

    2012-04-01

    We performed suppression subtractive hybridization to identify genomic differences between Streptococcus mitis and Streptococcus pneumoniae. Based on the pheA gene, a primer set specific to S. mitis detection was found in 18 out of 103 S. mitis-specific clones. Our findings would be useful for discrimination of S. mitis from other closely related cocci in the oral environment.

  19. The Effects of Mapping Instruction on Children's Procedural Bugs in Subtraction.

    ERIC Educational Resources Information Center

    Omanson, Susan F.; And Others

    This study was designed to follow up earlier work on mapping instruction. The two main goals were to: (1) test the effectiveness of mapping instruction as a general cure for "buggy" subtraction algorithms, and (2) explore two alternative explanations of how this new form of instruction works. It was hypothesized that mapping cures bugs…

  20. Utilizing a Collaborative Cross Number Puzzle Game to Develop the Computing Ability of Addition and Subtraction

    ERIC Educational Resources Information Center

    Chen, Yen-Hua; Looi, Chee-Kit; Lin, Chiu-Pin; Shao, Yin-Juan; Chan, Tak-Wai

    2012-01-01

    While addition and subtraction is a key mathematical skill for young children, a typical activity for them in classrooms involves doing repetitive arithmetic calculation exercises. In this study, we explore a collaborative way for students to learn these skills in a technology-enabled way with wireless computers. Two classes, comprising a total of…

  1. Issues relating to the subtraction phase in EOG artefact correction of the EEG.

    PubMed

    Croft, Rodney J; Barry, Robert J

    2002-06-01

    An important method for removing the effect of ocular artefact from the EEG is 'EOG correction'. This method estimates the proportion of ocular artefact that is in the EEG, and removes it by subtraction. To date, EOG correction research has focused on problems relating to the estimation of the correction coefficients. Using both mathematical rationale and empirical data, this paper addresses issues relating to the subtraction phase, such as the magnitude of error that can be expected due to EOG correction. Using ERP methodology, principal component and regression analyses, it is shown that the N1P2 complex propagates forward to the horizontal and radial (but not vertical) electrooculograms (EOG), and it is shown mathematically that this will result in EOG-correction error. Assuming an accurate estimate of ocular contamination of the EEG, maximal subtraction-phase error of the N1P2 complex was found to be a prefrontal attenuation of 15-22%, decreasing to central and occipital enhancements of 3-4% and 13-14%, respectively. The magnitude of this subtraction-phase error is compared to between-subject ERP variability and to error associated with EOG rejection (omitting data contaminated by ocular artefact). It is argued that such EOG correction error is small relative to both artefact rejection procedures and to normal variability found in ERP studies, and that it is less pernicious than artefact rejection procedures.

  2. Teaching Arithmetic: Lessons for Addition and Subtraction. Grades 2-3.

    ERIC Educational Resources Information Center

    Tank, Bonnie; Zolli, Lynne

    This book contains a collection of addition and subtraction lessons that support curriculum and instruction. The activities are rich with child-friendly contexts that are fun and engaging and give students opportunities to gain computational skills while developing their own confidence in and enjoyment of mathematics. Three elements are regarded…

  3. Correlated noise in networks of gravitational-wave detectors: Subtraction and mitigation

    NASA Astrophysics Data System (ADS)

    Thrane, E.; Christensen, N.; Schofield, R. M. S.; Effler, A.

    2014-07-01

    One of the key science goals of advanced gravitational-wave detectors is to observe a stochastic gravitational-wave background. However, recent work demonstrates that correlated magnetic fields from Schumann resonances can produce correlated strain noise over global distances, potentially limiting the sensitivity of stochastic background searches with advanced detectors. In this paper, we estimate the correlated noise budget for the worldwide advanced detector network and conclude that correlated noise may affect upcoming measurements. We investigate the possibility of a Wiener filtering scheme to subtract correlated noise from Advanced LIGO searches, and estimate the required specifications. We also consider the possibility that residual correlated noise remains following subtraction, and we devise an optimal strategy for measuring astronomical parameters in the presence of correlated noise. Using this new formalism, we estimate the loss of sensitivity for a broadband, isotropic stochastic background search using 1 yr of LIGO data at design sensitivity. Given our current noise budget, the uncertainty with which LIGO can estimate energy density will likely increase by a factor of ≈12—if it is impossible to achieve significant subtraction. Additionally, narrow band cross-correlation searches may be severely affected at low frequencies f ≲70 Hz without effective subtraction.

  4. Elaboration and research of planetary precessional multiplier type K-H-V

    NASA Astrophysics Data System (ADS)

    Bostan, I.; Dulgheru, V.; Ciobanu, R.

    2016-08-01

    The multiplier is an indispensable part of the micro hydropower plant and high power wind turbine. It helps to increase rotor low speeds limited by the water flow small velocity and by the relative big placement diameter of the blades that participate in the energy conversion. For example, the microhydrostation rotor's speed is (2 - 3) min'1 for water flow velocity V= (1...1,6) m/s and for blade placement diameter D = 4 m. Diversity of requirements forwarded by the beneficiaries of mechanical transmissions consists, in particular, in increasing reliability, efficiency and lifting capacity, and in reducing the mass and dimensions. It becomes more and more difficult to satisfy the mentioned demands by partial updating of traditional transmissions. The target problem can be solved with special effects by developing new types of multipliers based on precessional planetary transmissions with multiple gear, that were developed by the authors. Absolute multiplicity of precessional gear (up to 100% pairs of teeth simultaneously involved in gearing, compared to 5%-7% - in classical gearings) provides increased lifting capacity and small mass and dimensions. To mention that until now precessional planetary transmissions have been researched and applied mainly in reducers. Therefore it was necessary to carry out theoretical research to determine the geometrical parameters of the precessional gear that operates in multiplier mode. Also, it was necessary to develop new conceptual diagrams of precessional transmissions that function under multiplier regime. The majority of precessional planetary transmissions diagrams developed previously operate efficiently in reducer's regime. Depending on the structural diagram, precessional transmissions fall into two main types - K-H-V and 2K-H, from which a wide range of constructive solutions with wide kinematical and functional options that operate in multiplier regime.

  5. Characterization of avirulent mutant Legionella pneumophila that survive but do not multiply within human monocytes

    PubMed Central

    1987-01-01

    Legionella pneumophila, the causative agent of Legionnaires' disease, is a Gram-negative bacterium and a facultative intracellular parasite that multiplies in human monocytes and alveolar macrophages. In this paper, mutants of L. pneumophila avirulent for human monocytes were obtained and extensively characterized. The mutants were obtained by serial passage of wild-type L. pneumophila on suboptimal artificial medium. None of 44 such mutant clones were capable of multiplying in monocytes or exerting a cytopathic effect on monocyte monolayers. Under the same conditions, wild-type L. pneumophila multiplied 2.5-4.5 logs, and destroyed the monocyte monolayers. The basis for the avirulent phenotype was an inability of the mutants to multiply intracellularly. Both mutant and wild-type bacteria bound to and were ingested by monocytes, and both entered by coiling phagocytosis. Thereafter, their intracellular destinies diverged. The wild-type formed a distinctive ribosome-lined replicative phagosome, inhibited phagosome-lysosome fusion, and multiplied intracellularly. The mutant did not form the distinctive phagosome nor inhibit phagosome-lysosome fusion. The mutant survived intracellularly but did not replicate in the phagolysosome. In all other respects studied, the mutant and wild-type bacteria were similar. They had similar ultrastructure and colony morphology; both formed colonies of compact and diffuse type. They had similar structural and secretory protein profiles and LPS profile by PAGE. Both the mutant and wild-type bacteria were completely resistant to human complement in the presence or absence of high titer anti-L. pneumophila antibody. The mutant L. pneumophila have tremendous potential for enhancing our understanding of the intracellular biology of L. pneumophila and other parasites that follow a similar pathway through the mononuclear phagocyte. Such mutants also show promise for enhancing our understanding of immunity to L. pneumophila, and they may serve

  6. Computed tomography lung iodine contrast mapping by image registration and subtraction

    NASA Astrophysics Data System (ADS)

    Goatman, Keith; Plakas, Costas; Schuijf, Joanne; Beveridge, Erin; Prokop, Mathias

    2014-03-01

    Pulmonary embolism (PE) is a relatively common and potentially life threatening disease, affecting around 600,000 people annually in the United States alone. Prompt treatment using anticoagulants is effective and saves lives, but unnecessary treatment risks life threatening haemorrhage. The specificity of any diagnostic test for PE is therefore as important as its sensitivity. Computed tomography (CT) angiography is routinely used to diagnose PE. However, there are concerns it may over-report the condition. Additional information about the severity of an occlusion can be obtained from an iodine contrast map that represents tissue perfusion. Such maps tend to be derived from dual-energy CT acquisitions. However, they may also be calculated by subtracting pre- and post-contrast CT scans. Indeed, there are technical advantages to such a subtraction approach, including better contrast-to-noise ratio for the same radiation dose, and bone suppression. However, subtraction relies on accurate image registration. This paper presents a framework for the automatic alignment of pre- and post-contrast lung volumes prior to subtraction. The registration accuracy is evaluated for seven subjects for whom pre- and post-contrast helical CT scans were acquired using a Toshiba Aquilion ONE scanner. One hundred corresponding points were annotated on the pre- and post-contrast scans, distributed throughout the lung volume. Surface-to-surface error distances were also calculated from lung segmentations. Prior to registration the mean Euclidean landmark alignment error was 2.57mm (range 1.43-4.34 mm), and following registration the mean error was 0.54mm (range 0.44-0.64 mm). The mean surface error distance was 1.89mm before registration and 0.47mm after registration. There was a commensurate reduction in visual artefacts following registration. In conclusion, a framework for pre- and post-contrast lung registration has been developed that is sufficiently accurate for lung subtraction

  7. Low-power microelectromechanically tunable silicon photonic ring resonator add-drop filter.

    PubMed

    Errando-Herranz, Carlos; Niklaus, Frank; Stemme, Göran; Gylfason, Kristinn B

    2015-08-01

    We experimentally demonstrate a microelectromechanically (MEMS) tunable photonic ring resonator add-drop filter, fabricated in a simple silicon-on-insulator (SOI) based process. The device uses electrostatic parallel plate actuation to perturb the evanescent field of a silicon waveguide, and achieves a 530 pm resonance wavelength tuning, i.e., more than a fourfold improvement compared to previous MEMS tunable ring resonator add-drop filters. Moreover, our device has a static power consumption below 100 nW, and a tuning rate of -62  pm/V, i.e., the highest reported rate for electrostatic tuning of ring resonator add-drop filters.

  8. EPA adds Old American Zinc in Fairmont City to Superfund cleanup list

    EPA Pesticide Factsheets

    For Immediate Release No. 16-OPA009 EPA adds Old American Zinc in Fairmont City to Superfund cleanup list CHICAGO (April 6, 2016) - U.S. Environmental Protection Agency today announced that the Old American Zinc

  9. U.S. EPA Proposes to Add California Mine Site to Superfunds National Priorities List

    EPA Pesticide Factsheets

    SAN FRANCISCO - The U.S. Environmental Protection Agency is proposing to add eight hazardous waste sites to the Superfund program's National Priorities List (NPL), including California's Argonaut Mine. Superfund is the federal program that investiga

  10. Add More Vegetables to Your Day: 10 Tips to Help You Eat More Vegetables

    MedlinePlus

    ... dish to add to any meal. Steam green beans, carrots, or broccoli in a bowl with a ... salad by using colorful vegetables such as black beans, sliced red bell peppers, shredded radishes, chopped red ...

  11. EPA Adds Sites to National Priorities List to Reduce Risk to Public Health and Environment

    EPA Pesticide Factsheets

    WASHINGTON - The U.S. Environmental Protection Agency (EPA) is adding five and proposing to add eight hazardous waste sites to the Superfund program's National Priorities List (NPL). These are sites with known or threatened hazardous waste releases

  12. Mothers whose children have ADD/ADHD discuss their children's medication use: an investigation of blogs.

    PubMed

    Clarke, Juanne N; Lang, Laura

    2012-01-01

    This article presents the results of a frame and discourse analysis of Internet blog sites where parents (usually mothers) discuss their concerns about medication use by their children with attention deficit disorder or attention deficit hyperactivity disorder (ADD/ADHD). This is a particularly important topic in an era characterized by powerful circulating discourses around the contentious medicalization of, and prevalent pharmaceutical treatments for, ADD/ADHD, as well as the mother blame associated with having a child diagnosed with ADD/ADHD. The findings document that the mothers see ADD/ADHD as legitimate medical diagnoses and view themselves as caretakers of children with brain and neuro-chemical anomalies affecting the behavior of their children. They favor pharmaceutical use and describe themselves as experts in the difficult and complex issues related to pharmaceuticalized parenting. At the same time their adoption of medicalization is contingent as they express specific critiques of some doctors, some types of doctors, and critically evaluate science.

  13. Registration characteristics of neutral particles with power 0.6 - 2.0 keV channel electron multiplier with funnel

    NASA Technical Reports Server (NTRS)

    Gruntman, M. A.; Kalinin, A. P.

    1978-01-01

    Operating a channel electron multiplier with a VEU-6 funnel shaped opening is studied. Different procedures were used when recording neutral particles. The results obtained make it possible to optimally use the multiplier in actual physical studies.

  14. LANDSAT-D project ADDS/LAS. Scrounge interface control document

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The content and format of all data to be exchanged between the Applications Developmental data System (ADDS) and the LANDSAT-D Assessment System (LAS) for satisfaction of early access thematic mapper product generation requirements is specified. The ADDS provides partially processed TM data tapes on CCT's. The LANDSAT-D Assessment System processes the TM data to fully processed data tapes on 6250 bpi computer compatible tapes and provides required film data products.

  15. Genetic dissection of Helicobacter pylori AddAB role in homologous recombination.

    PubMed

    Marsin, Stéphanie; Lopes, Anne; Mathieu, Aurélie; Dizet, Eléa; Orillard, Emilie; Guérois, Raphaël; Radicella, J Pablo

    2010-10-01

    Helicobacter pylori infects the stomach of about half of the world's human population, frequently causing chronic inflammation at the origin of several gastric pathologies. One of the most remarkable characteristics of the species is its remarkable genomic plasticity in which homologous recombination (HR) plays a critical role. Here, we analyzed the role of the H. pylori homologue of the AddAB recombination protein. Bioinformatics analysis of the proteins unveils the similarities and differences of the H. pylori AddAB complex with respect to the RecBCD and AddAB complexes from Escherichia coli and Bacillus subtilis, respectively. Helicobacter pylori mutants lacking functional addB or/and addA show the same level of sensitivity to DNA-damaging agents such as UV or irradiation and of deficiency in intrachromosomal RecA-dependent HR. Epistasis analyses of both DNA repair and HR phenotypes, using double and triple recombination mutants, demonstrate that, in H. pylori, AddAB and RecOR complexes define two separate presynaptic pathways with little functional overlap. However, neither of these complexes participates in the RecA-dependent process of transformation of these naturally competent bacteria.

  16. The National Longitudinal Study of Adolescent Health (Add Health) sibling pairs data.

    PubMed

    Harris, Kathleen Mullan; Halpern, Carolyn Tucker; Haberstick, Brett C; Smolen, Andrew

    2013-02-01

    This article describes the design and phenotype and genotype data available for sibling pairs with varying genetic relatedness in the National Longitudinal Study of Adolescent Health (Add Health). Add Health is a nationally representative longitudinal study of over 20,000 adolescents in the United States in 1994-1995 who have been followed for 15 years into adulthood. The Add Health design included oversamples of more than 3,000 pairs of individuals with varying genetic resemblance, ranging from monozygotic twins, dizygotic twins, full siblings, half siblings, and unrelated siblings who were raised in the same household. Add Health sibling pairs are therefore nationally representative and followed longitudinally from early adolescence into adulthood with four in-home interviews during the period 1994-2009. Add Health has collected rich longitudinal social, behavioral, environmental, and biological data, as well as buccal cell DNA from all sample members, including sibling pairs. Add Health has an enlightened dissemination policy and to date has released phenotype and genotype data to more than 10,000 researchers in the scientific community.

  17. Effect and Potential Mechanism of Electroacupuncture Add-On Treatment in Patients with Parkinson's Disease.

    PubMed

    Wang, Fang; Sun, Li; Zhang, Xiao-Zhe; Jia, Jun; Liu, Zhuo; Huang, Xi-Yan; Yu, Shu-Yang; Zuo, Li-Jun; Cao, Chen-Jie; Wang, Xiao-Min; Zhang, Wei

    2015-01-01

    Objectives. To explore effectiveness and mechanisms of electroacupuncture (EA) add-on treatment in Parkinson's disease (PD) patients. Methods. Fifty PD patients were randomly assigned to drug plus EA (D + EA) group and drug alone (D) group. Subjects in D + EA group received stimulation in points of bilateral fengfu, fengchi, hegu, and central dazhui. Participants were evaluated by scales for motor and nonmotor symptoms. Levels of neuroinflammatory factors and neurotransmitters in serum were detected. Results. EA add-on treatment remarkably reduced scores of Unified Parkinson's Disease Rating Scale (UPDRS) III and its subitems of tremor, rigidity, and bradykinesia and conspicuously decreased UPDRS III scores in patients with bradykinesia-rigidity and mixed types and mild severity. Depression and sleep disturbances were eased, which were reflected by decreased scores of Hamilton Depression Rating Scale, Pittsburgh Sleep Quality Index, and elevated noradrenaline level. Effects of EA add-on treatment on motor symptoms and sleep disturbances were superior to drug alone treatment, markedly improving life quality of PD patients. EA add-on treatment decreased nitric oxide level in serum. Conclusions. EA add-on treatment is effective on most motor symptoms and some nonmotor symptoms and is particularly efficacious in PD patients at early stage. Antineuroinflammation may be a mechanism of EA add-on treatment.

  18. A role for α-adducin (ADD-1) in nematode and human memory.

    PubMed

    Vukojevic, Vanja; Gschwind, Leo; Vogler, Christian; Demougin, Philippe; de Quervain, Dominique J-F; Papassotiropoulos, Andreas; Stetak, Attila

    2012-03-21

    Identifying molecular mechanisms that underlie learning and memory is one of the major challenges in neuroscience. Taken the advantages of the nematode Caenorhabditis elegans, we investigated α-adducin (add-1) in aversive olfactory associative learning and memory. Loss of add-1 function selectively impaired short- and long-term memory without causing acquisition, sensory, or motor deficits. We showed that α-adducin is required for consolidation of synaptic plasticity, for sustained synaptic increase of AMPA-type glutamate receptor (GLR-1) content and altered GLR-1 turnover dynamics. ADD-1, in a splice-form- and tissue-specific manner, controlled the storage of memories presumably through actin-capping activity. In support of the C. elegans results, genetic variability of the human ADD1 gene was significantly associated with episodic memory performance in healthy young subjects. Finally, human ADD1 expression in nematodes restored loss of C. elegans add-1 gene function. Taken together, our findings support a role for α-adducin in memory from nematodes to humans. Studying the molecular and genetic underpinnings of memory across distinct species may be helpful in the development of novel strategies to treat memory-related diseases.

  19. Casimir energy in a small volume multiply connected static hyperbolic preinflationary universe

    SciTech Connect

    Mu''ller, Daniel; Fagundes, Helio V.; Opher, Reuven

    2001-06-15

    A few years ago, Cornish, Spergel and Starkman (CSS) suggested that a multiply connected ''small'' universe could allow for classical chaotic mixing as a preinflationary homogenization process. The smaller the volume, the more important the process. Also, a smaller universe has a greater probability of being spontaneously created. Previously DeWitt, Hart and Isham (DHI) calculated the Casimir energy for static multiply connected flat space-times. Because of the interest in small volume hyperbolic universes (e.g., CSS), we generalize the DHI calculation by making a numerical investigation of the Casimir energy for a conformally coupled, massive scalar field in a static universe, whose spatial sections are the Weeks manifold, the smallest universe of negative curvature known. In spite of being a numerical calculation, our result is in fact exact. It is shown that there is spontaneous vacuum excitation of low multipolar components.

  20. Effect of cooling on the efficiency of Schottky varactor frequency multipliers at millimeter waves

    NASA Technical Reports Server (NTRS)

    Louhi, Jyrki; Raiesanen, Antti; Erickson, Neal

    1992-01-01

    The efficiency of the Schottky diode multiplier can be increased by cooling the diode to 77 K. The main reason for better efficiency is the increased mobility of the free carriers. Because of that the series resistance decreases and a few dB higher efficiency can be expected at low input power levels. At high output frequencies and at high power levels, the current saturation decreases the efficiency of the multiplication. When the diode is cooled the maximum current of the diode increases and much more output power can be expected. There are also slight changes in the I-V characteristic and in the diode junction capacitance, but they have a negligible effect on the efficiency of the multiplier.

  1. The Lagrangian multiplier method of finding upper and lower limits to critical stresses of clamped plates

    NASA Technical Reports Server (NTRS)

    Budiansky, Bernard; Hu, Pai C

    1946-01-01

    The theory of Lagrangian multipliers is applied to the problem of finding both upper and lower limits to the true compressive buckling stress of a clamped rectangular plate. The upper and lower limits thus bracket the true stress, which cannot be exactly found by the differential-equation approach. The procedure for obtaining the upper limit, which is believed to be new, presents certain advantages over the classical Rayleigh-Ritz method of finding upper limits. The theory of the lower-limit procedure has been given by Trefftz, but, in the present application, the method differs from that of Trefftz in a way that makes it inherently more quickly convergent. It is expected that in other buckling problems and in some vibration problems the Lagrangian multiplier method of finding upper and lower limits may be advantageously applied to the calculation of buckling stresses and natural frequencies.

  2. Three-body neutral dissociations of a multiply excited water molecule around the double ionization potential

    NASA Astrophysics Data System (ADS)

    Odagiri, Takeshi; Nakano, Motoyoshi; Tanabe, Takehiko; Kumagai, Yoshiaki; Suzuki, Isao H.; Kitajima, Masashi; Kouchi, Noriyuki

    2012-11-01

    The cross sections for emission of two fluorescence photons from a pair of excited fragments in photoexcitation of H2O have been measured as a function of the incident photon energy using the photon-photon coincidence technique. The cross section increased in the range 30-45 eV, i.e. in the vicinity of the double ionization potential of H2O. The increase of the cross section was attributed to three-body neutral dissociations of a water molecule via multiply excited states: H2O** → H(2p) + OH** → H(2p) + H(2p) + O(3P). Some multiply excited states of H2O were also found in the cross section curve around 65 eV.

  3. On the design of a radix-10 online floating-point multiplier

    NASA Astrophysics Data System (ADS)

    McIlhenny, Robert D.; Ercegovac, Milos D.

    2009-08-01

    This paper describes an approach to design and implement a radix-10 online floating-point multiplier. An online approach is considered because it offers computational flexibility not available with conventional arithmetic. The design was coded in VHDL and compiled, synthesized, and mapped onto a Virtex 5 FPGA to measure cost in terms of LUTs (look-up-tables) as well as the cycle time and total latency. The routing delay which was not optimized is the major component in the cycle time. For a rough estimate of the cost/latency characteristics, our design was compared to a standard radix-2 floating-point multiplier of equivalent precision. The results demonstrate that even an unoptimized radix-10 online design is an attractive implementation alternative for FPGA floating-point multiplication.

  4. An algorithm to design finite field multipliers using a self-dual normal basis

    NASA Technical Reports Server (NTRS)

    Wang, C. C.

    1987-01-01

    Finite field multiplication is central in the implementation of some error-correcting coders. Massey and Omura have presented a revolutionary design for multiplication in a finite field. In their design, a normal base is utilized to represent the elements of the field. The concept of using a self-dual normal basis to design the Massey-Omura finite field multiplier is presented. Presented first is an algorithm to locate a self-dual normal basis for GF(2 sup m) for odd m. Then a method to construct the product function for designing the Massey-Omura multiplier is developed. It is shown that the construction of the product function base on a self-dual basis is simpler than that based on an arbitrary normal base.

  5. Noise limitations of multiplier phototubes in the radiation environment of space

    NASA Technical Reports Server (NTRS)

    Viehmann, W.; Eubanks, A. G.

    1976-01-01

    The contributions of Cerenkov emission, luminescence, secondary electron emission, and bremsstrahlung to radiation-induced data current and noise of multiplier phototubes were analyzed quantitatively. Fluorescence and Cerenkov emission in the tube window are the major contributors and can quantitatively account for dark count levels observed in orbit. Radiation-induced noise can be minimized by shielding, tube selection, and mode of operation. Optical decoupling of windows and cathode (side-window tubes) leads to further reduction of radiation-induced dark counts, as does reducing the window thickness and effective cathode area, and selection of window/cathode combinations of low fluorescence efficiency. In trapped radiation-free regions of near-earth orbits and in free space, Cerenkov emission by relativistic particles contributes predominantly to the photoelectron yield per event. Operating multiplier phototubes in the photon (pulse) counting mode will discriminate against these large pulses and substantially reduce the dark count and noise to levels determined by fluorescence.

  6. On-Chip Power-Combining for High-Power Schottky Diode-Based Frequency Multipliers

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Goutam; Mehdi, Imran; Schlecht, Erich T.; Lee, Choonsup; Siles, Jose V.; Maestrini, Alain E.; Thomas, Bertrand; Jung, Cecile D.

    2013-01-01

    A 1.6-THz power-combined Schottky frequency tripler was designed to handle approximately 30 mW input power. The design of Schottky-based triplers at this frequency range is mainly constrained by the shrinkage of the waveguide dimensions with frequency and the minimum diode mesa sizes, which limits the maximum number of diodes that can be placed on the chip to no more than two. Hence, multiple-chip power-combined schemes become necessary to increase the power-handling capabilities of high-frequency multipliers. The design presented here overcomes difficulties by performing the power-combining directly on-chip. Four E-probes are located at a single input waveguide in order to equally pump four multiplying structures (featuring two diodes each). The produced output power is then recombined at the output using the same concept.

  7. Multiply periodic states and isolated skyrmions in an anisotropic frustrated magnet

    PubMed Central

    Leonov, A. O.; Mostovoy, M.

    2015-01-01

    Multiply periodic states appear in a wide variety of physical contexts, such as the Rayleigh–Bénard convection, Faraday waves, liquid crystals and skyrmion crystals recently observed in chiral magnets. Here we study the phase diagram of an anisotropic frustrated magnet which contains five different multiply periodic states including the skyrmion crystal. We clarify the mechanism for stabilization of these states and discuss how they can be observed in magnetic resonance and electric polarization measurements. We also find stable isolated skyrmions with topological charge 1 and 2. Their spin structure, interactions and dynamics are more complex than those in chiral magnets. In particular, magnetic resonance in the skyrmion crystal should be accompanied by oscillations of the electric polarization with a frequency depending on the amplitude of the a.c. magnetic field. These results show that skyrmion materials with rich physical properties can be found among frustrated magnets. We formulate rules to help the search. PMID:26394924

  8. A mixed element based on Lagrange multiplier method for modified couple stress theory

    NASA Astrophysics Data System (ADS)

    Kwon, Young-Rok; Lee, Byung-Chai

    2017-01-01

    A 2D mixed element is proposed for the modified couple stress theory. The C1 continuity for the displacement field is required because of the second derivatives of displacement in the energy form of the theory. The C1 continuity is satisfied in a weak sense with the Lagrange multiplier method. A supplementary rotation is introduced as an independent variable and the kinematic relation between the physical rotation and the supplementary rotation is constrained with Lagrange multipliers. Convergence criteria and a stability condition are derived, and the number and the positions of nodes for each independent variable are determined. Internal degrees of freedom are condensed out, so the element has only 21 degrees of freedom. The proposed element passes the C^{0-1} patch test. Numerical results show that the principle of limitation is applied to the element and the element is robust to mesh distortion. Furthermore, the size effects are captured well with the element.

  9. Bacillus subtilis Swarmer Cells Lead the Swarm, Multiply, and Generate a Trail of Quiescent Descendants

    PubMed Central

    Hamouche, Lina; Laalami, Soumaya; Daerr, Adrian; Song, Solène; Holland, I. Barry; Séror, Simone J.; Hamze, Kassem

    2017-01-01

    ABSTRACT Bacteria adopt social behavior to expand into new territory, led by specialized swarmers, before forming a biofilm. Such mass migration of Bacillus subtilis on a synthetic medium produces hyperbranching dendrites that transiently (equivalent to 4 to 5 generations of growth) maintain a cellular monolayer over long distances, greatly facilitating single-cell gene expression analysis. Paradoxically, while cells in the dendrites (nonswarmers) might be expected to grow exponentially, the rate of swarm expansion is constant, suggesting that some cells are not multiplying. Little attention has been paid to which cells in a swarm are actually multiplying and contributing to the overall biomass. Here, we show in situ that DNA replication, protein translation and peptidoglycan synthesis are primarily restricted to the swarmer cells at dendrite tips. Thus, these specialized cells not only lead the population forward but are apparently the source of all cells in the stems of early dendrites. We developed a simple mathematical model that supports this conclusion. PMID:28174308

  10. A mixed element based on Lagrange multiplier method for modified couple stress theory

    NASA Astrophysics Data System (ADS)

    Kwon, Young-Rok; Lee, Byung-Chai

    2016-11-01

    A 2D mixed element is proposed for the modified couple stress theory. The C1 continuity for the displacement field is required because of the second derivatives of displacement in the energy form of the theory. The C1 continuity is satisfied in a weak sense with the Lagrange multiplier method. A supplementary rotation is introduced as an independent variable and the kinematic relation between the physical rotation and the supplementary rotation is constrained with Lagrange multipliers. Convergence criteria and a stability condition are derived, and the number and the positions of nodes for each independent variable are determined. Internal degrees of freedom are condensed out, so the element has only 21 degrees of freedom. The proposed element passes the C^{0-1} patch test. Numerical results show that the principle of limitation is applied to the element and the element is robust to mesh distortion. Furthermore, the size effects are captured well with the element.

  11. Modulation of the neutron field in the multiplying condensed matter and coolant

    SciTech Connect

    Vodyanitskii, A. A.; Slyusarenko, Yu. V.

    2009-12-14

    The spatial damping of acoustic, neutron and thermal branches of oscillations are found in neutron multiplying medium with coolant. All three branches give additive contribution to the neutron density oscillations. However, their wave numbers and coefficients of spatial damping (at the same frequency) differ greatly from the sound with its high phase velocity and small attenuation to the neutron wave with the damping length, which is comparable with its wavelength. A spatial growth of neutron density oscillations is found in the case of large frequency of neutron capture and weak coupling of neutron density and temperature branches of oscillations. This fact is of importance for the noise diagnostics of the multiplying medium with coolant. The results can be applied to the development of the methods of noise diagnostics of the in core reactor equipment.

  12. On isochronous cases of the Cherkas system and Jacobi's last multiplier

    NASA Astrophysics Data System (ADS)

    Ghose Choudhury, A.; Guha, Partha

    2010-03-01

    We consider a large class of polynomial planar differential equations proposed by Cherkas (1976 Differensial'nye Uravneniya 12 201-6), and show that these systems admit a Lagrangian description via the Jacobi last multiplier (JLM). It is shown how the potential term can be mapped either to a linear harmonic oscillator potential or into an isotonic potential for specific values of the coefficients of the polynomials. This enables the identification of the specific cases of isochronous motion without making use of the computational procedure suggested by Hill et al (2007 Nonlinear Anal.: Theor. Methods Appl. 67 52-69), based on the Pleshkan algorithm. Finally, we obtain a Lagrangian description and perform a similar analysis for a cubic system to illustrate the applicability of this procedure based on Jacobi's last multiplier. birthday with great respect and admiration.

  13. Preconditioned alternating direction method of multipliers for inverse problems with constraints

    NASA Astrophysics Data System (ADS)

    Jiao, Yuling; Jin, Qinian; Lu, Xiliang; Wang, Weijie

    2017-02-01

    We propose a preconditioned alternating direction method of multipliers (ADMM) to solve linear inverse problems in Hilbert spaces with constraints, where the feature of the sought solution under a linear transformation is captured by a possibly non-smooth convex function. During each iteration step, our method avoids solving large linear systems by choosing a suitable preconditioning operator. In case the data is given exactly, we prove the convergence of our preconditioned ADMM without assuming the existence of a Lagrange multiplier. In case the data is corrupted by noise, we propose a stopping rule using information on noise level and show that our preconditioned ADMM is a regularization method; we also propose a heuristic rule when the information on noise level is unavailable or unreliable and give its detailed analysis. Numerical examples are presented to test the performance of the proposed method.

  14. Effects of layer-multiplying and interface on the content of β-transcrystallization in PP

    SciTech Connect

    Lei, Fan; Li, Jiang E-mail: nic7702@scu.edu.cn; Guo, Shaoyun E-mail: nic7702@scu.edu.cn

    2015-05-22

    The alternating multilayered polypropylene (PP layer)/β-nucleating agent filled-polypropylene (β-PP layer) were prepared through layer-multiplying extrusion combined with an assembly of layer-multiplying elements (LM Es). The content of β-crystal was firstly evaluated by differential scanning calorimetry (DSC), which indicated that the relative amount of the β-crystal increased from 38.67% to 81.22% with the increase of layer numbers from 2-layer to 128-layer. It was well consistent with the results of X-ray diffraction (XRD). The morphology observation of β-crystal by polarizing microscope (POM) revealed that the closely packed nuclei in the interface could induce numerous β-transcrystallization in pure PP layer due to the confinement effect. The non-isothermal crystallization kinetic analysis via Mozhishen’s methods manifested that the crystallization rate was greatly enhanced by the augment of the layered interface.

  15. Theoretical and experimental analysis of the lubricating system of a high speed multiplier

    NASA Astrophysics Data System (ADS)

    Marian, V. G.; Mirică, R. F.; Prisecaru, T.

    2017-02-01

    Flywheel-based energy storage systems are used for energy storage in form of kinetic energy using a flywheel rotating at high speed. In order to achieve this high rotating speed a high speed multiplier could be used in order to increase the rotation speed of a conventional motor. This article presents a theoretical and experimental analysis of the lubricating system of a high speed multiplier used in a flywheel-based energy storage system. The necessary oil flow is theoretically computed using analytical formulas. The oil is used for lubricating the gears, the roller bearings and the sliding bearings. An experimental test rig is used to measure the oil flow. Finally the two results are compared.

  16. A new frequency-multiplied interferometer system in the GAMMA 10 tandem mirror.

    PubMed

    Kohagura, J; Yoshikawa, M; Shima, Y; Morikawa, Y; Yamada, T; Akita, D; Tatebe, K; Ichimura, M; Hirata, M; Ikezoe, R; Yokoyama, T; Imai, T

    2012-10-01

    A new interferometer is installed on the west anchor cell of the GAMMA 10 tandem mirror. In GAMMA 10, we have used a heterodyne-type interferometer with a 70-GHz IMPATT oscillator and a 150-MHz oscillator for frequency modulation. The new interferometer consists of a 17.5-GHz phase locked dielectric resonator oscillator and a 37.5-MHz temperature-compensated crystal oscillator, as well as frequency multipliers. The main motivation for the new interferometer using frequency multipliers is to achieve a stable and cost effective interferometer. Direct anchor heating experiments with new anchor ion cyclotron range of frequency antennas in both the west and the east anchor cells are carried out. Density increases in both anchor cells are clearly observed using the new interferometer.

  17. Frequency multiplying oscillator with an electron beam accelerated in a drift space

    SciTech Connect

    Jang, Kyu-Ha; Lee, Kitae; Hee Park, Seong; Uk Jeong, Young; Miginsky, S.

    2012-07-02

    In a uniform acceleration region, the behavior of a velocity-modulated electron beam has been analyzed using a particle-in-cell code. By making use of one of the accelerated harmonic components of the velocity-modulated electron beam, we demonstrate a frequency multiplying oscillator for a compact THz emitter, which employs multiple electron beams and a higher order mode resonator to modulate the electron beam without an additional driving source.

  18. A Lagrange multiplier mixed finite element formulation for three-dimensional contact of biphasic tissues.

    PubMed

    Yang, Taiseung; Spilker, Robert L

    2007-06-01

    A three-dimensional (3D) contact finite element formulation has been developed for biological soft tissue-to-tissue contact analysis. The linear biphasic theory of Mow, Holmes, and Lai (1984, J. Biomech., 17(5), pp. 377-394) based on continuum mixture theory, is adopted to describe the hydrated soft tissue as a continuum of solid and fluid phases. Four contact continuity conditions derived for biphasic mixtures by Hou et al. (1989, ASME J. Biomech. Eng., 111(1), pp. 78-87) are introduced on the assumed contact surface, and a weighted residual method has been used to derive a mixed velocity-pressure finite element contact formulation. The Lagrange multiplier method is used to enforce two of the four contact continuity conditions, while the other two conditions are introduced directly into the weighted residual statement. Alternate formulations are possible, which differ in the choice of continuity conditions that are enforced with Lagrange multipliers. Primary attention is focused on a formulation that enforces the normal solid traction and relative fluid flow continuity conditions on the contact surface using Lagrange multipliers. An alternate approach, in which the multipliers enforce normal solid traction and pressure continuity conditions, is also discussed. The contact nonlinearity is treated with an iterative algorithm, where the assumed area is either extended or reduced based on the validity of the solution relative to contact conditions. The resulting first-order system of equations is solved in time using the generalized finite difference scheme. The formulation is validated by a series of increasingly complex canonical problems, including the confined and unconfined compression, the Hertz contact problem, and two biphasic indentation tests. As a clinical demonstration of the capability of the contact analysis, the gleno-humeral joint contact of human shoulders is analyzed using an idealized 3D geometry. In the joint, both glenoid and humeral head

  19. Efficiency and weight of voltage multiplier type ultra lightweight dc-dc converters

    NASA Technical Reports Server (NTRS)

    Harrigill, W. T., Jr.; Myers, I. T.

    1975-01-01

    An analytical and experimental study was made of a capacitor-diode voltage multiplier without a transformer which offers the possibility of high efficiency with light weight. The dc-dc conversion efficiencies of about 94 percent were achieved at output powers of 150 watts at 1000 volts using 8x multiplication. A detailed identification of losses was made, including forward drop losses in component, switching losses, reverse junction capacitance charging losses, and charging losses in the main ladder capacitors.

  20. Split-Waveguide Mounts For Submillimeter-Wave Multipliers And Harmonic Mixers

    NASA Technical Reports Server (NTRS)

    Raisanen, Antti; Choudhury, Debabani; Dengler, Robert J.; Oswald, John E.; Siegel, Peter H.

    1996-01-01

    Novel variation of split-waveguide mount for millimeter-and submillimeter-wavelength frequency multipliers and harmonic mixers developed. Designed to offer wide range of available matching impedances, while maintaining relatively simple fabrication sequence. Wide tuning range achieved with separate series and parallel elements, consisting of two pairs of noncontacting sliding backshorts, at fundamental and harmonic frequencies. Advantages include ease of fabrication, reliability, and tunability.