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Sample records for fast time response

  1. Distinguishing Fast and Slow Processes in Accuracy - Response Time Data.

    Frederik Coomans

    Full Text Available We investigate the relation between speed and accuracy within problem solving in its simplest non-trivial form. We consider tests with only two items and code the item responses in two binary variables: one indicating the response accuracy, and one indicating the response speed. Despite being a very basic setup, it enables us to study item pairs stemming from a broad range of domains such as basic arithmetic, first language learning, intelligence-related problems, and chess, with large numbers of observations for every pair of problems under consideration. We carry out a survey over a large number of such item pairs and compare three types of psychometric accuracy-response time models present in the literature: two 'one-process' models, the first of which models accuracy and response time as conditionally independent and the second of which models accuracy and response time as conditionally dependent, and a 'two-process' model which models accuracy contingent on response time. We find that the data clearly violates the restrictions imposed by both one-process models and requires additional complexity which is parsimoniously provided by the two-process model. We supplement our survey with an analysis of the erroneous responses for an example item pair and demonstrate that there are very significant differences between the types of errors in fast and slow responses.

  2. Distinguishing Fast and Slow Processes in Accuracy - Response Time Data.

    Coomans, Frederik; Hofman, Abe; Brinkhuis, Matthieu; van der Maas, Han L J; Maris, Gunter

    2016-01-01

    We investigate the relation between speed and accuracy within problem solving in its simplest non-trivial form. We consider tests with only two items and code the item responses in two binary variables: one indicating the response accuracy, and one indicating the response speed. Despite being a very basic setup, it enables us to study item pairs stemming from a broad range of domains such as basic arithmetic, first language learning, intelligence-related problems, and chess, with large numbers of observations for every pair of problems under consideration. We carry out a survey over a large number of such item pairs and compare three types of psychometric accuracy-response time models present in the literature: two 'one-process' models, the first of which models accuracy and response time as conditionally independent and the second of which models accuracy and response time as conditionally dependent, and a 'two-process' model which models accuracy contingent on response time. We find that the data clearly violates the restrictions imposed by both one-process models and requires additional complexity which is parsimoniously provided by the two-process model. We supplement our survey with an analysis of the erroneous responses for an example item pair and demonstrate that there are very significant differences between the types of errors in fast and slow responses. PMID:27167518

  3. Digital timing algorithms applied to fast scintillators response

    The future Facility for Antiproton and Ion Research (FAIR) will house the calorimeter and spectrometer CALIFA, whose design, construction and testing are currently being carried out by the R3B collaboration. The mentioned calorimeter is an array of scintillation detectors displayed in a barrel configuration, which covers the total solid angle. These new fast scintillation materials have been developed in last few years and their main interest lies on their versatility, which allows their use both for applications and fundamental research. In the same way, fast digitizers let the collection of signals at increasingly higher sampling frequencies. Our research takes advantage of these fair properties and is therefore focused on the analysis of digitized pulses for several aims: understanding the behaviour of radiation inside new fast scintillators and the development or improvement of digital algorithms which yield accurate resolution for fast timing and may be also applied to particle identification.

  4. Study of the time response of a LuAG(Pr) crystal for fast timing applications

    Fraile, L. M.; Mach, H.; Picado, E.; Vedia, V.; Udías, J. M.

    2013-06-01

    The recently developed praseodymium-doped lutetium aluminum garnet, LuAG(Pr), holds a strong potential for fast timing applications. In this study we report on the time response of LuAG(Pr) at 22Na and 60Co photon energies. The measurements were performed using a small crystal cube of 1 cm3 coupled to a Hamamatsu R5320 photomultiplier tube. The full width at half maximum (FWHM) time resolution is found to be 147±2 ps at 60Co energies, and 238±2 ps at 22Na.

  5. Study of the time response of a LuAG(Pr) crystal for fast timing applications

    The recently developed praseodymium-doped lutetium aluminum garnet, LuAG(Pr), holds a strong potential for fast timing applications. In this study we report on the time response of LuAG(Pr) at 22Na and 60Co photon energies. The measurements were performed using a small crystal cube of 1 cm3 coupled to a Hamamatsu R5320 photomultiplier tube. The full width at half maximum (FWHM) time resolution is found to be 147±2 ps at 60Co energies, and 238±2 ps at 22Na

  6. Ultra-Fast Flash Observatory: Fast Response Space Missions for Early Time Phase of Gamma Ray Bursts

    Park, I.H.; Ahmad, S.; Barrillon, P.;

    2013-01-01

    -second response, for the first time, opening a completely new frontier in GRB and transient studies. Its fast response measurements of the optical emission of dozens of GRB each year will provide unique probes of the burst mechanism and test the prospect of GRB as a new standard candle, potentially opening up the...

  7. Development of multi-layer thin film bolometer with fast time response and high sensitivity

    Impurity radiation loss is one of major cooling mechanisms in a fusion plasma. A multi-layer thin film bolometer with high sensitivity and fast time response has been developed for the measurement of radiation energy loss of a screw pinch plasma in TPE-2 device. The construction and test of the bolometer are described. High sensitivity of 2.5 mV/μ Joule and fast time response of 10 μsec with cooling time of 50 msec are obtained. (author)

  8. Wide dynamic range neutron flux monitor having fast time response for the Large Helical Device

    A fast time response, wide dynamic range neutron flux monitor has been developed toward the LHD deuterium operation by using leading-edge signal processing technologies providing maximum counting rate up to ∼5 × 109 counts/s. Because a maximum total neutron emission rate over 1 × 1016 n/s is predicted in neutral beam-heated LHD plasmas, fast response and wide dynamic range capabilities of the system are essential. Preliminary tests have demonstrated successful performance as a wide dynamic range monitor along the design

  9. Timing and position response of a block detector for fast neutron time-of-flight imaging

    Our research effort seeks to improve the spatial and timing performance of a block detector made of a pixilated plastic scintillator (EJ-200), first demonstrated as part of Oak Ridge National Laboratory's Advanced Portable Neutron Imaging System. Improvement of the position and time response is necessary to achieve better resolution and contrast in the images of shielded special nuclear material. Time-of-flight is used to differentiate between gamma and different sources of neutrons (e.g., transmission and fission neutrons). Factors limiting the timing and position performance of the neutron detector have been revealed through simulations and measurements. Simulations have suggested that the degradation in the ability to resolve pixels in the neutron detector is due to those interactions occurring near the light guide. The energy deposition within the neutron detector is shown to affect position performance and imaging efficiency. This examination details how energy cuts improve the position performance and degrade the imaging efficiency. Measurements have shown the neutron detector to have a timing resolution of σ=238 ps. The majority of this timing uncertainty is from the depth-of-interaction (DOI) of the neutron which is confirmed by simulations and analytical calculations

  10. A new fast-response, real-time and continuous dissolved methane sensor.

    Triest, Jack; Chappellaz, Jerome; Grilli, Roberto

    2016-04-01

    Continuous high resolution profiling of dissolved methane down to ocean depths is made possible as a result of technological innovations achieved in the search for the oldest ice in Antarctica. Testing for the SUBGLACIOR probe, which is being developed at LGGE in response to the IPICS >1Ma old ice challenge, showed that much of the technology to extract the trapped gases from ice can also significantly improve the extraction and analysis of dissolved methane from the sea compared to current available sensors. To develop this potential, an oceanographic instrument 'SubOcean' was built and deployed over a gas-hydrate zone of western Svalbard, in collaboration with CAGE, in October 2015. Continuous measurements to depths of 400 m were made over three days resulting in high-resolution 3D profiles. The very fast response time of the sensor allows to display the in-situ measurements in real-time and compare them directly to data from other instrumentation aboard the ship whilst underway. The sensor contains a membrane based gas extraction system coupled to a laser spectrometer to provide accurate measurements over a wide concentration range. We will present the overall design of the instrument and highlight how it can help provide new insights into the spatial distribution and flux of methane in the marine environment.

  11. Real-time Holographic Display Based on a Super Fast Response Thin Film

    Real-time dynamic holographic display is obtained with super fast response in a thin film without any applied electric field. Holograms can be refreshed in the order of a millisecond and there is no cross talk between the recorded holograms because the hologram formed in the film is transient and can be completely self erased, and the hologram formation time and self-erasure time are both ∼1 ms. Holographic video display is achieved, which shows the real-time holographic image display capability of the thin film, and its much higher resolution than those of commercially available spatial light modulators. Furthermore, multiplexed hologram display using two polarization directions of a recorded light and multiple color holographic display at different laser wavelengths are presented, which demonstrate the feasibility of a RGB color holographic three-dimensional display with the thin film. Because the sample is easy to be fabricated into a large size screen and needs no external applied electric field, we think that the film can be developed into a large-size, dynamic, and color holographic three-dimensional display in the future.

  12. Design of a test system for fast time response fibre optic oxygen sensors

    A test system has been developed that can be used to calibrate and determine the time response, linearity and temperature sensitivity of a fibre optic oxygen sensor. The simple system obviates the need for precision gas standards and the requirement to generate a true square wave step response, which is seldom achievable. The sensor is mounted in a small chamber containing air or a known fraction of oxygen. By means of a computer-controlled switch, the absolute pressure within the chamber can be changed rapidly to a new steady state value. The partial pressure of oxygen changes in direct proportion to the absolute pressure, and so the accuracy and linearity and response time of the PO2 calibration are limited only by those of the absolute pressure sensor. The temperature sensitivity of a commercial sensor and a means of correction are also described. (note)

  13. Sampling frequency, response times and embedded signal filtration in fast, high efficiency liquid chromatography: A tutorial.

    Wahab, M Farooq; Dasgupta, Purnendu K; Kadjo, Akinde F; Armstrong, Daniel W

    2016-02-11

    With increasingly efficient columns, eluite peaks are increasingly narrower. To take full advantage of this, choice of the detector response time and the data acquisition rate a.k.a. detector sampling frequency, have become increasingly important. In this work, we revisit the concept of data sampling from the theorem variously attributed to Whittaker, Nyquist, Kotelnikov, and Shannon. Focusing on time scales relevant to the current practice of high performance liquid chromatography (HPLC) and optical absorbance detection (the most commonly used method), even for very narrow simulated peaks Fourier transformation shows that theoretical minimum sampling frequency is still relatively low (digital filters. We show that the common wisdom of sampling 20 points per peak can be inadequate for high efficiency columns and that the sampling frequency and response choices do affect the peak shape. If the sampling frequency is too low or response time is too large, the observed peak shapes will not remain as narrow as they really are - this is especially true for high efficiency and high speed separations. It is shown that both sampling frequency and digital filtering affect the retention time, noise amplitude, peak shape and width in a complex fashion. We show how a square-wave driven light emitting diode source can reveal the nature of the embedded filter. We discuss time uncertainties related to the choice of sampling frequency. Finally, we suggest steps to obtain optimum results from a given system. PMID:26803000

  14. Study of bi-alkali photocathode growth on glass by X-ray techniques for fast timing response photomultipliers

    Xie, Junqi; Demarteau, Marcel; Wagner, Robert; Ruiz-Oses, Miguel; Liang, Xue; Ben-Zvi, Ilan; Attenkofer, Klaus; Schubert, Susanne; Smedley, John; Wong, Jared; Padmore, Howard; Woll, Arthur

    2014-03-01

    Bi-alkali antimonide photocathode is an essential component in fast timing response photomultipliers. Real-time in-situ grazing incidence x-ray diffraction and post-growth x-ray reflectivity measurement were performed to study the photocathode deposition process on glass substrate. Grazing incidence x-ray diffraction patterns show the formation of Sb crystalline, dissolution of crystalline phase Sb by the application of K vapor and reformation of refined crystal textures. XRR result exhibits that the film thickness increases ~ 4.5 times after K diffusion and almost have no change after Cs diffusion. Further investigation is expected to understand the photocathode growth process and provide guidelines for photocathode development.

  15. A fast-time-response extreme ultraviolet spectrometer for measurement of impurity line emissions in the Experimental Advanced Superconducting Tokamak.

    Zhang, Ling; Morita, Shigeru; Xu, Zong; Wu, Zhenwei; Zhang, Pengfei; Wu, Chengrui; Gao, Wei; Ohishi, Tetsutarou; Goto, Motoshi; Shen, Junsong; Chen, Yingjie; Liu, Xiang; Wang, Yumin; Dong, Chunfeng; Zhang, Hongmin; Huang, Xianli; Gong, Xianzu; Hu, Liqun; Chen, Junlin; Zhang, Xiaodong; Wan, Baonian; Li, Jiangang

    2015-12-01

    A flat-field extreme ultraviolet (EUV) spectrometer working in the 20-500 Å wavelength range with fast time response has been newly developed to measure line emissions from highly ionized tungsten in the Experimental Advanced Superconducting Tokamak (EAST) with a tungsten divertor, while the monitoring of light and medium impurities is also an aim in the present development. A flat-field focal plane for spectral image detection is made by a laminar-type varied-line-spacing concave holographic grating with an angle of incidence of 87°. A back-illuminated charge-coupled device (CCD) with a total size of 26.6 × 6.6 mm(2) and pixel numbers of 1024 × 255 (26 × 26 μm(2)/pixel) is used for recording the focal image of spectral lines. An excellent spectral resolution of Δλ0 = 3-4 pixels, where Δλ0 is defined as full width at the foot position of a spectral line, is obtained at the 80-400 Å wavelength range after careful adjustment of the grating and CCD positions. The high signal readout rate of the CCD can improve the temporal resolution of time-resolved spectra when the CCD is operated in the full vertical binning mode. It is usually operated at 5 ms per frame. If the vertical size of the CCD is reduced with a narrow slit, the time response becomes faster. The high-time response in the spectral measurement therefore makes possible a variety of spectroscopic studies, e.g., impurity behavior in long pulse discharges with edge-localized mode bursts. An absolute intensity calibration of the EUV spectrometer is also carried out with a technique using the EUV bremsstrahlung continuum at 20-150 Å for quantitative data analysis. Thus, the high-time resolution tungsten spectra have been successfully observed with good spectral resolution using the present EUV spectrometer system. Typical tungsten spectra in the EUV wavelength range observed from EAST discharges are presented with absolute intensity and spectral identification. PMID:26724029

  16. A fast-time-response extreme ultraviolet spectrometer for measurement of impurity line emissions in the Experimental Advanced Superconducting Tokamak

    Zhang, Ling; Xu, Zong; Wu, Zhenwei; Zhang, Pengfei; Wu, Chengrui; Gao, Wei; Shen, Junsong; Chen, Yingjie; Liu, Xiang; Wang, Yumin; Gong, Xianzu; Hu, Liqun; Chen, Junlin; Zhang, Xiaodong; Wan, Baonian; Li, Jiangang [Institute of Plasma Physics Chinese Academy of Sciences, Hefei 230026, Anhui (China); Morita, Shigeru; Ohishi, Tetsutarou; Goto, Motoshi [National Institute for Fusion Science, Toki 509-5292, Gifu (Japan); Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu (Japan); Dong, Chunfeng [Southwestern Institute of Physics, Chengdu 610041, Sichuan (China); and others

    2015-12-15

    A flat-field extreme ultraviolet (EUV) spectrometer working in the 20-500 Å wavelength range with fast time response has been newly developed to measure line emissions from highly ionized tungsten in the Experimental Advanced Superconducting Tokamak (EAST) with a tungsten divertor, while the monitoring of light and medium impurities is also an aim in the present development. A flat-field focal plane for spectral image detection is made by a laminar-type varied-line-spacing concave holographic grating with an angle of incidence of 87°. A back-illuminated charge-coupled device (CCD) with a total size of 26.6 × 6.6 mm{sup 2} and pixel numbers of 1024 × 255 (26 × 26 μm{sup 2}/pixel) is used for recording the focal image of spectral lines. An excellent spectral resolution of Δλ{sub 0} = 3-4 pixels, where Δλ{sub 0} is defined as full width at the foot position of a spectral line, is obtained at the 80-400 Å wavelength range after careful adjustment of the grating and CCD positions. The high signal readout rate of the CCD can improve the temporal resolution of time-resolved spectra when the CCD is operated in the full vertical binning mode. It is usually operated at 5 ms per frame. If the vertical size of the CCD is reduced with a narrow slit, the time response becomes faster. The high-time response in the spectral measurement therefore makes possible a variety of spectroscopic studies, e.g., impurity behavior in long pulse discharges with edge-localized mode bursts. An absolute intensity calibration of the EUV spectrometer is also carried out with a technique using the EUV bremsstrahlung continuum at 20-150 Å for quantitative data analysis. Thus, the high-time resolution tungsten spectra have been successfully observed with good spectral resolution using the present EUV spectrometer system. Typical tungsten spectra in the EUV wavelength range observed from EAST discharges are presented with absolute intensity and spectral identification.

  17. Fast response liquid crystal devices

    Wu, Yung-Hsun

    Liquid crystal (LC) has been widely used for displays, spatial light modulators, variable optical attenuators (VOAs) and other tunable photonic devices. The response time of these devices is mainly determined by the employed liquid crystal material. The response time of a LC device depends on the visco-elastic coefficient (gamma1/K11), LC cell gap (d), and applied voltage. Hence, low visco-elastic coefficient LC materials and thinner cell gap are favorable for reducing the response time. However, low visco-elastic coefficient LCs are usually associated with a low birefringence because of shorter molecular conjugation. For display applications, such as LCD TVs, low birefringence (Deltanthick cell gap which, in turn, increases the response time. How to obtain fast response for the LC devices is a fundamentally important and technically challenging task. In this dissertation, we investigate several methods to improve liquid crystal response time, for examples, using dual-frequency liquid crystals, polymer stabilized liquid crystals, and sheared polymer network liquid crystals. We discover a new class of material, denoted as sheared polymer network liquid crystal (SPNLC) which exhibits a submillisecond response time. Moreover, this response time is insensitive to the LC cell gap. This is the first LC device exhibiting such an interesting property. Chapters 1 and 2 describe the motivation and background of this dissertation. From chapter 3 to chapter 6, dual-frequency liquid crystals and polymer network methods are demonstrated as examples for the variable optical attenuators. Variable optical attenuator (VOA) is a key component in optical communications. Especially, the sheared PNLC VOA shows the best result; its dynamic range reaches 43 dB while the response time is in the submillisecond range at 1550 nm wavelength, which is 50 times faster than the commercial LC-based VOA. In Chapter 7, we report a new device called axially-symmetric sheared polymer network liquid

  18. Fast Food Problems and Responsibilities

    Zhang; Jing

    2015-01-01

    <正>People are living in a world that acquires almost everyone to chase efficiency and speed.The real inner quality of daily life is not approximately taken into people’s consideration.Fast food is one of the common model reactions of this rapid developing society.Recently,it’s getting popular that people would rather have fast food to save time for other extra work.Problems and public concern are following that kind of life condition and someone or something should be put blame on for this.

  19. The time-walk of analog constant fraction discriminators using very fast scintillator detectors with linear and non-linear energy response

    The electronic γ–γ fast timing technique allows for direct nuclear lifetime determination down to the few picoseconds region by measuring the time difference between two coincident γ-ray transitions. Using high resolution ultra-fast LaBr3(Ce) scintillator detectors in combination with the recently developed mirror symmetric centroid difference method, nuclear lifetimes are measured with a time resolving power of around 5 ps. The essence of the method is to calibrate the energy dependent position (centroid) of the prompt response function of the setup which is obtained for simultaneously occurring events. This time-walk of the prompt response function induced by the analog constant fraction discriminator has been determined by systematic measurements using different photomultiplier tubes and timing adjustments of the constant fraction discriminator. We propose a universal calibration function which describes the time-walk or the combined γ–γ time-walk characteristics, respectively, for either a linear or a non-linear amplitude versus energy dependency of the scintillator detector output pulses.

  20. Enhanced photoacoustic gas analyser response time and impact on accuracy at fast ventilation rates during multiple breath washout.

    Alex Horsley

    Full Text Available BACKGROUND: The Innocor device contains a highly sensitive photoacoustic gas analyser that has been used to perform multiple breath washout (MBW measurements using very low concentrations of the tracer gas SF6. Use in smaller subjects has been restricted by the requirement for a gas analyser response time of <100 ms, in order to ensure accurate estimation of lung volumes at rapid ventilation rates. METHODS: A series of previously reported and novel enhancements were made to the gas analyser to produce a clinically practical system with a reduced response time. An enhanced lung model system, capable of delivering highly accurate ventilation rates and volumes, was used to assess in vitro accuracy of functional residual capacity (FRC volume calculation and the effects of flow and gas signal alignment on this. RESULTS: 10-90% rise time was reduced from 154 to 88 ms. In an adult/child lung model, accuracy of volume calculation was -0.9 to 2.9% for all measurements, including those with ventilation rate of 30/min and FRC of 0.5 L; for the un-enhanced system, accuracy deteriorated at higher ventilation rates and smaller FRC. In a separate smaller lung model (ventilation rate 60/min, FRC 250 ml, tidal volume 100 ml, mean accuracy of FRC measurement for the enhanced system was minus 0.95% (range -3.8 to 2.0%. Error sensitivity to flow and gas signal alignment was increased by ventilation rate, smaller FRC and slower analyser response time. CONCLUSION: The Innocor analyser can be enhanced to reliably generate highly accurate FRC measurements down at volumes as low as those simulating infant lung settings. Signal alignment is a critical factor. With these enhancements, the Innocor analyser exceeds key technical component recommendations for MBW apparatus.

  1. Preoperative fasting time in children.

    Adeel, S

    2012-02-01

    The aim of preoperative fasting is to prevent regurgitation and pulmonary aspiration while limiting potential problems of thirst, dehydration and hypoglycaemia. The American Society of Anaesthesiologists (ASA) has suggested guidelines for preoperative fasting for children undergoing elective surgery. We did a postal survey to determine the current practice regarding these guidelines amongst all specialist registrars in anaesthesia in Ireland. A questionnaire was sent to all specialist registrars in anaesthesia (90 in total), 60 (67%) were returned and analysed. The question asked was how long children should be kept fasting before elective surgery. The results of our survey suggest that most of the respondents are following the ASA guidelines for clear fluids and solids however there were differing opinion regarding the duration of fasting for formula milk and breast milk. In conclusion, we would recommend greater awareness and collaboration between anaesthetists, nurses and surgeons to ensure that fasting instructions are consistent with the ASA guidelines and that patient and their parents understand these directives as well.

  2. Fast response stainless steel sodium thermocouple

    Thermo electro motive force and transient response characteristics of well-type stainless steel sodium thermocouples have been studied. The experiments were performed with a specially constructed test rig allowing the placement of several couples at various depths of immersion in liquid sodium and at different spacings. The time response was studied by inducing temperature transients in a hot sodium injection and gas injection, and photographing the oscilloscope trace of the output. The possibility of using these thermocouples in transit time flowmeters in sodium circuit was ascertained by observing the response from two thermocouples in flowing sodium, and evaluating the cross-correlation between the response. The application of such thermocouples for fast reactors and sodium circuits is also discussed. (author)

  3. The high contrast ratio and fast response time of a liquid crystal display lit by a carbon nanotube field emission backlight unit

    We report on the fabrication of a carbon nanotube field emission backlight unit (CNT-BLU) and its application for liquid crystal displays (LCD). The CNT-BLU was operated with locally controllable luminance and impulse-type scanning. The local luminance control, which is based on a very small block size of 1 cm2, consisted of local dimming and local brightening. This resulted in the contrast ratio of the LCD-TV to be as high as 300 000:1. A fast response time of ∼5.7 ms was also achieved from the LCD-TV lit by CNT-BLU, originating from the impulse-type scanning. In addition, the CNT-BLU showed long-term emission stability and high luminance uniformity

  4. A new scintillation counter with very fast resolving time (1961)

    The rare gases used as scintillators are characterized by their short time of luminescence and by the linearity of their response as a function of the total energy imparted to the gas by the incident particle. It is possible with these scintillators, when associated with a fast response photomultiplier, to solve certain problems of nuclear physics demanding a linear detector with a very fast resolving time (a few nanoseconds). Two examples of the construction of this apparatus are described. The results obtained and future possibilities are briefly outlined. (author)

  5. Fast response bolometer for high temperature plasma

    A fast response bolometer is developed to measure the radiation loss from a high temperature plasma. Radiation from the plasma (mainly x-ray) is absorbed by a thin foil and heats it up. Change in far infrared (FIR) radiation, due to the change in temperature, emitted from the back surface of the foil is detected by an FIR detector which is contained in a shield box placed distant from a plasma generating machine to eliminate electrical noise. The FIR radiation is transmitted from the thin foil to the detector by a light pipe (metal pipe inner surface of which is polished). The foil (radiation absorber) consists of 5μm thick copper foil, both surfaces of which are coated with 1 μm thick carbon to increase the sensitivity and to simplify the calibration procedure. Calibration is done by two methods: One is to obtain the relation between temperature of the foil and the output of the detector. The other is to measure the detector output when the foil is illuminated by a flashlight with known light energy. Latter calibration procedure is excellent in that it is reliable and can be carried out with the same arrangement as the radiation from the plasma is measured. The result of this calibration is 0.46mV/mJ. This figure can be increased by adoption of FIR light collecting system. Time response of the bolometer (conduction of heat from radiation absorbing surface to the back surface of the foil) is calculated to be 400 ns. The thickness of the foil is chosen in such a way that the radiation from the plasma with electron temperature of about 100 eV is almost completely absorbed. This bolometer is applicable to plasmas with higher temperature when the foil thickness is increased with the sacrifice of time response and sensitivity. (author)

  6. Fast response Full Bridge Power Factor Corrector

    Chan, CH; Pong, MH

    1998-01-01

    A fast response Full Bridge Power Factor Corrector (FBPFC) is presented in this paper. The converter is combined by two interleaved boost cells and a conventional full bridge converter. As the interleaving technique is applied, the input ripple current of FBPFC are reduced. Experimental result shows that the maximum power factor is 0.98 even without input filter.

  7. Fast response to human voices in autism.

    Lin, I-Fan; Agus, Trevor R; Suied, Clara; Pressnitzer, Daniel; Yamada, Takashi; Komine, Yoko; Kato, Nobumasa; Kashino, Makio

    2016-01-01

    Individuals with autism spectrum disorders (ASD) are reported to allocate less spontaneous attention to voices. Here, we investigated how vocal sounds are processed in ASD adults, when those sounds are attended. Participants were asked to react as fast as possible to target stimuli (either voices or strings) while ignoring distracting stimuli. Response times (RTs) were measured. Results showed that, similar to neurotypical (NT) adults, ASD adults were faster to recognize voices compared to strings. Surprisingly, ASD adults had even shorter RTs for voices than the NT adults, suggesting a faster voice recognition process. To investigate the acoustic underpinnings of this effect, we created auditory chimeras that retained only the temporal or the spectral features of voices. For the NT group, no RT advantage was found for the chimeras compared to strings: both sets of features had to be present to observe an RT advantage. However, for the ASD group, shorter RTs were observed for both chimeras. These observations indicate that the previously observed attentional deficit to voices in ASD individuals could be due to a failure to combine acoustic features, even though such features may be well represented at a sensory level. PMID:27193919

  8. Time of flight fast neutron radiography

    Neutron radiography with fast or thermal neutrons is a standard technique for non-destructive testing (NDT). Here we report results for fast neutron radiography both as an adjunct to pulsed fast neutron analysis (PFNA) and as a stand-alone method for NDT. PFNA is a new technique for utilizing a collimated pulsed neutron beam to interrogate items and determine their elemental composition. By determining the time of flight for gamma-rays produced by (n,n' gamma X) reactions, a three dimensional image can be produced. Neutron radiography data taken with the same beam provides an important constraint for image reconstruction, and in particular is important in inferring the amount of hydrogen within the interrogated item. As a stand-alone device, the radiography measurement can be used to image items as large as cargo containers as long as their density is not too high. The use of a pulsed beam gives the further advantage of a time of flight measurement on the transmitted neutrons. By gating the radiography signal on the time of flight appropriate to the energy of the primary neutrons, most build-up from scattered neutrons can be eliminated. The pulsed beam also greatly improves the signal to background and extends the range of the neutron radiography. Simulation results will be presented which display the advantage of this constraint in particular for statistically limited data. Experimental results will be presented which show some of the limitations likely in a PFNA system utilizing neutron radiography data. Experimental and simulation results will demonstrate possible uses for this type of radiographic data in identifying contraband substances such as drugs. (orig.)

  9. Evaluation of Fast-Time Wake Vortex Prediction Models

    Proctor, Fred H.; Hamilton, David W.

    2009-01-01

    Current fast-time wake models are reviewed and three basic types are defined. Predictions from several of the fast-time models are compared. Previous statistical evaluations of the APA-Sarpkaya and D2P fast-time models are discussed. Root Mean Square errors between fast-time model predictions and Lidar wake measurements are examined for a 24 hr period at Denver International Airport. Shortcomings in current methodology for evaluating wake errors are also discussed.

  10. Concomitant effects of Ramadan fasting and time-of-day on apolipoprotein AI, B, Lp-a and homocysteine responses during aerobic exercise in Tunisian soccer players.

    Omar Hammouda

    Full Text Available OBJECTIVE: To examine the time-of-day and Ramadan fasting (RF effects on serum apolipoprotein-AI (Apo-AI and B (Apo-B, lipoprotein particles-a (Lp-a, high-sensitive C-reactive-protein (hs-CRP, and homocysteine (Hcy during the Yo-Yo intermittent recovery test (YYIRT. DESIGN: Performance and biochemical measures were completed at two times-of-day (07:00 and 17:00 h, 1-week before RF (BR, the second week of RF (SWR, and the fourth week of RF (ER. SETTING: For each session, subjects performed the YYIRT, and blood samples were taken before and 3-min after the test for biochemical measures. PARTICIPANTS: Fifteen soccer players. MAIN OUTCOME MEASURES: Total distance during the YYIRT, core temperature, body composition, dietary intakes, lipid (HDL-C, LDL-C, Apo-AI, B and Lp-a and inflammatory (hs-CRP and Hcy profiles. RESULTS: Performances during the YYIRT were higher in the evening than the morning BR (P < 0.05, but this fluctuation was not observed during RF. Moreover, LDL-C, ApoB, and Lp-a were stable throughout the daytime BR. However, during RF, they decreased at 17:00 h (P < 0.05. Likewise, HDL-C and Apo-AI increased after the exercise and were higher at 17:00 h BR (P < 0.001. Moreover, these parameters increased during RF (P < 0.01. Furthermore, Hcy and hs-CRP increased during the exercise (P < 0.01 with higher evening levels BR. During ER, the diurnal pattern of Hcy was inversed (P < 0.001. CONCLUSIONS: This study concluded that caloric restriction induced by RF seems to ameliorate lipid and inflammatory markers of cardiovascular health during intermittent exercise performed in the evening.

  11. The Fast Tracker Real Time Processor

    Annovi, A; The ATLAS collaboration

    2011-01-01

    As the LHC luminosity is ramped up to the SLHC Phase I level and beyond, the high rates, multiplicities, and energies of particles seen by the detectors will pose a unique challenge. Only a tiny fraction of the produced collisions can be stored on tape and immense real-time data reduction is needed. An effective trigger system must maintain high trigger efficiencies for the physics we are most interested in, and at the same time suppress the enormous QCD backgrounds. This requires massive computing power to minimize the online execution time of complex algorithms. A multi-level trigger is an effective solution for an otherwise impossible problem. The Fast Tracker (FTK)[1], is a proposed upgrade to the current ATLAS trigger system that will operate at full Level-1 output rates and provide high quality tracks reconstructed over the entire detector by the start of processing in Level-2. FTK solves the combinatorial challenge inherent to tracking by exploiting massive parallelism of associative memories [2] that ...

  12. Response measurement of single-crystal chemical vapor deposition diamond radiation detector for intense X-rays aiming at neutron bang-time and neutron burn-history measurement on an inertial confinement fusion with fast ignition.

    Shimaoka, T; Kaneko, J H; Arikawa, Y; Isobe, M; Sato, Y; Tsubota, M; Nagai, T; Kojima, S; Abe, Y; Sakata, S; Fujioka, S; Nakai, M; Shiraga, H; Azechi, H; Chayahara, A; Umezawa, H; Shikata, S

    2015-05-01

    A neutron bang time and burn history monitor in inertial confinement fusion with fast ignition are necessary for plasma diagnostics. In the FIREX project, however, no detector attained those capabilities because high-intensity X-rays accompanied fast electrons used for plasma heating. To solve this problem, single-crystal CVD diamond was grown and fabricated into a radiation detector. The detector, which had excellent charge transportation property, was tested to obtain a response function for intense X-rays. The applicability for neutron bang time and burn history monitor was verified experimentally. Charge collection efficiency of 99.5% ± 0.8% and 97.1% ± 1.4% for holes and electrons were obtained using 5.486 MeV alpha particles. The drift velocity at electric field which saturates charge collection efficiency was 1.1 ± 0.4 × 10(7) cm/s and 1.0 ± 0.3 × 10(7) cm/s for holes and electrons. Fast response of several ns pulse width for intense X-ray was obtained at the GEKKO XII experiment, which is sufficiently fast for ToF measurements to obtain a neutron signal separately from X-rays. Based on these results, we confirmed that the single-crystal CVD diamond detector obtained neutron signal with good S/N under ion temperature 0.5-1 keV and neutron yield of more than 10(9) neutrons/shot. PMID:26026521

  13. A proposal for fast neutron personal real time dosimetry in mixed n, γ fields

    A method for fast neutron monitoring has been studied, resulting from computer simulation analysis of fast neutron and gamma interaction responses in silicon counters. A real time personal dosemeter with a response accuracy better than 30% in a mixed n, γ field for neutron energies between 0.75 and 15 MeV is proposed. (author)

  14. A fast-response microfiber coupler tip high temperature sensor

    Ding, M; Wang, Pengfei; Brambilla, G.

    2012-01-01

    A compact fast temperature sensor based on a broadband microfiber coupler tip is demonstrated. The thermometer dynamic range spans from room temperature to 1511 °C with a response time of tens of ms. This is the highest temperature measured with an optical fiber device. The resolution of 0.66 °C was achieved for a coupler tip diameter of ~12.56 ?m.

  15. Fast-response beam loss monitor

    By connecting a polyethylene fiber to a photo-multiplier, a beam loss monitor with a fast response has been fabricated. The beam loss is measured by Cherenkov light generated by a charged particle penetrating a fiber. Although this monitor has the merits that the structure of the monitor is simple and cheap, it has the demerits that the signal has an energy dependence, and deterioration caused by radiation occurs. A plastic scintillating fiber and a quartz fiber have also been tested. The signal of the former fiber is strong and does not depend on the energy of the circulating beam. However, the deterioration is also very severe. On the contrary, the latter fiber has a long lifetime, though its signal is small. Some measurements are discussed here concerning various cases of extraction conditions. (author)

  16. Combined digital divice with fast response

    The article deals with a fast-acting, high-capacity counter. The first stages of the counter are built around a flip-flop circuit employing tunnel diodes and transistors. The integrated section of the circuit employs the NOR gates. The flip-flops are connected through the direct current-coupled circuit. Use is made of the fast-acting elements with emitter-coupled logic which makes it possible to insure the speediest operation of the flip-flop at a frequency of at least 70 MHz. Coupling with the flip-flops employing transistor-transistor logic is effected through a transition stage using the transistors. Resetting of the flip-flop is accomplished by one trigger pulse. The reset pulse is applied to each next flip-flop at a delay equal to the previous flip-flop operation time. Such a delay is insured by the RC-circuits. The information about the state of the flip-flops can be transferred to the pulse analyzer via buffer stages. The state of the flip-flops is visually checked through miniature glow lamps NCM-9-60 BM. The counter does not call for good shaping of input pulses with respect to amplitude and width. The maximum counting rate is 270 MHz

  17. Fission-neutrons source with fast neutron-emission timing

    Rusev, G.; Baramsai, B.; Bond, E. M.; Jandel, M.

    2016-05-01

    A neutron source with fast timing has been built to help with detector-response measurements. The source is based on the neutron emission from the spontaneous fission of 252Cf. The time is provided by registering the fission fragments in a layer of a thin scintillation film with a signal rise time of 1 ns. The scintillation light output is measured by two silicon photomultipliers with rise time of 0.5 ns. Overall time resolution of the source is 0.3 ns. Design of the source and test measurements using it are described. An example application of the source for determining the neutron/gamma pulse-shape discrimination by a stilbene crystal is given.

  18. Mutagenic response of peanut (arachis hypogaea L.) to fast neutrons

    Dominant seeds of peanut were treated with varying doses of fast neutrons employing efficient pre- and post-irradiation techniques for determination of various plant responses useful in a long range program of mutation breeding. Mean reductions in seedling height and frequency of M1 somatic mutations increased with increasing radiation dose. No reduction in M1 seedset was obtained even in the dose above the LD50 of 1600 rads. The frequency of M2 macromutations ranged from only 3.60 - 5.65 per 100 M2 plants. The genetic basis of each of these radiation responses is briefly discussed. The high sensitivity of M1 peanut seedlings and growing plants to fast neutrons is probably due to the highly differentiated seed embryo at the time of irradiation while the radioresistance exhibited by the matured plant appears to be related to the polyploid genome of the species. (Auth.)

  19. Fast response time alcohol gas sensor using nanocrystalline F-doped SnO2 films derived via sol–gel method

    Sarbani Basu; Yeong-Her Wang; C Ghanshyam; Pawan Kapur

    2013-08-01

    Pure and fluorine-modified tin oxide (SnO2) thin films (250–300 nm) were uniformly deposited on corning glass substrate using sol–gel technique to fabricate SnO2-based resistive sensors for ethanol detection. The characteristic properties of the multicoatings have been investigated, including their electrical conductivity and optical transparency in visible IR range. Pure SnO2 films exhibited a visible transmission of 90% compared with Fdoped films (80% for low doping and 60% for high doping). F-doped SnO2 films exhibited lower resistivity (0.12 × 10-4 cm) compared with the pure (14.16 × 10-4 cm) one. X-ray diffraction and scanning electron microscopy techniques were used to analyse the structure and surface morphology of the prepared films. Resistance change was studied at different temperatures (523–623 K) with metallic contacts of silver in air and in presence of different ethanol vapour concentrations. Comparative gas-sensing results revealed that the prepared F-doped SnO2 sensor exhibited the lowest response and recovery times of 10 and 13 s, respectively whereas that of pure SnO2 gas sensor, 32 and 65 s, respectively. The maximum sensitivities of both gas sensors were obtained at 623 K.

  20. Development of a small, nanosecond timing fast neutron spectrometer

    A neutron spectrometer has been developed for use inside a fast neutron assembly. The spectrometer is small and insensitive to gamma radiation. An optical system was developed which could collect about 80 per cent of the light from an NE213 liquid scintillator and transmit it along a 450 mm quartz light guide to a high performance photomultiplier. To enable the detector to be used as a nanosecond timing spectrometer, several calibration measurements were made of the detector efficiency and response to monoenergetic neutrons

  1. A fast response temperature sensor based on fiber Bragg grating

    Aimed at the requirement for a fast-response expendable ocean temperature sensor, this paper presents a new design scheme for an optic fiber sensor. Ocean temperature sensors require high sensitivity and high response speed, which must be up to milliseconds. The fiber Bragg grating (FBG) temperature sensor with high sensitivity has been declared in the last decade, but its response speed has been rarely reported. In this paper, a method is proposed which is to package an FBG with a metal tube. The response time of this sensor is 48.6 ms, which is an order of magnitude greater than that of an ordinary optical fiber temperature sensor. Temperature sensitivity is 27.6 pm/°C and the linearity is up to 0.9999. In addition, the sensor can be less than 15 mm. It offers a new way to detect ocean temperature. (paper)

  2. A thermometer for fast response in cryogenic flow

    The measurement of transient temperatures in cryogenic fluid flow requires a highly sensitive, intrinsically fast sensor that is in good thermal contact with the fluid but in poor thermal contact with the solid walls confining the fluid. A resistance thermometer made from a 1 μm thick silicon layer on a 125 μm thick sapphire substrate has a calculated intrinsic response time of about 10 ns at 4 K, and its sensitivity is comparable to germanium or carbon thermometers in the range of 1-80 K. This paper describes a novel construction method to mount the small silicon-on-sapphire thermometer in an oscillating fluid flow. The large surface area of the thermometer provides good thermal contact with the fluid, while the suspension ensures poor thermal contact with the holder, maintains its fast response time, and withstands high velocities and frequencies of fluid oscillation. A self-heating response time of 300 ns was measured at 4 K in liquid and gaseous helium. Repeatability of the thermometer is + or - 10 mK at 4 K. Examples of the performance of this thermometer for helium gas oscillations in the frequency range of 1 Hz to 12 kHz are given

  3. Initial Report of the Fast Timing Working Group

    CMS Collaboration

    2016-01-01

    A preliminary set of results highlighting the unique capabilities of fast-timing for resolving information from individual collisions at the High-Luminosity LHC (HL- LHC) is presented. These results explore the possibilities made available by using fast timing to enhance the reconstruction and physics capabilities of the CMS detector in terms of pileup mitigation and searches for new physics. Fast timing applications in calorimetry, for electromagnetic showers, and for MIPs, to time-tag tracks, are demonstrated as are first examples of what is possible with their combination.

  4. A new and highly selective turn-on fluorescent sensor with fast response time for the monitoring of cadmium ions in cosmetic, and health product samples

    Khani, Rouhollah; Ghiamati, Ebrahim; Boroujerdi, Ramin; Rezaeifard, Abdolreza; Zaryabi, Mohadeseh Hosseinpour

    2016-06-01

    Cadmium (Cd) which is an extremely toxic could be found in many products like plastics, fossil fuel combustion, cosmetics, water resources, and wastewaters. It is capable of causing serious environmental and health problems such as lung, prostate, renal cancers and the other disorders. So, the development of a sensor to continually monitor cadmium is considerably demanding. Tetrakis(4-nitrophenyl)porphyrin, T(4-NO2-P)P, was synthesized and used as a new and highly selective fluorescent probe for monitoring cadmium ions in the "turn-on" mode. There was a linear relationship between fluorescence intensity and the concentration of Cd(II) in the range of 1.0 × 10- 6 to 1.0 × 10- 5 mol L- 1 with a detection limit of 0.276 μM. To examine the most important parameters involved and their interactions in the sensor optimization procedure, a four-factor central composite design (CCD) combined with response surface modeling (RSM) was implemented. The practical applicability of the developed sensor was investigated using real cosmetic, and personal care samples.

  5. A new and highly selective turn-on fluorescent sensor with fast response time for the monitoring of cadmium ions in cosmetic, and health product samples.

    Khani, Rouhollah; Ghiamati, Ebrahim; Boroujerdi, Ramin; Rezaeifard, Abdolreza; Zaryabi, Mohadeseh Hosseinpour

    2016-06-15

    Cadmium (Cd) which is an extremely toxic could be found in many products like plastics, fossil fuel combustion, cosmetics, water resources, and wastewaters. It is capable of causing serious environmental and health problems such as lung, prostate, renal cancers and the other disorders. So, the development of a sensor to continually monitor cadmium is considerably demanding. Tetrakis(4-nitrophenyl)porphyrin, T(4-NO2-P)P, was synthesized and used as a new and highly selective fluorescent probe for monitoring cadmium ions in the "turn-on" mode. There was a linear relationship between fluorescence intensity and the concentration of Cd(II) in the range of 1.0×10(-6) to 1.0×10(-5)molL(-1) with a detection limit of 0.276μM. To examine the most important parameters involved and their interactions in the sensor optimization procedure, a four-factor central composite design (CCD) combined with response surface modeling (RSM) was implemented. The practical applicability of the developed sensor was investigated using real cosmetic, and personal care samples. PMID:27045784

  6. Fast timing methods for semiconductor detectors. Revision

    This tutorial paper discusses the basic parameters which determine the accuracy of timing measurements and their effect in a practical application, specifically timing with thin-surface barrier detectors. The discussion focusses on properties of the detector, low-noise amplifiers, trigger circuits and time converters. New material presented in this paper includes bipolar transistor input stages with noise performance superior to currently available FETs, noiseless input terminations in sub-nanosecond preamplifiers and methods using transmission lines to couple the detector to remotely mounted preamplifiers. Trigger circuits are characterized in terms of effective rise time, equivalent input noise and residual jitter

  7. Response times to conceptual questions

    Lasry, Nathaniel; Watkins, Jessica; Mazur, Eric; Ibrahim, Ahmed

    2013-09-01

    We measured the time taken by students to respond to individual Force Concept Inventory (FCI) questions. We examine response time differences between correct and incorrect answers, both before and after instruction. We also determine the relation between response time and expressed confidence. Our data reveal three results of interest. First, response times are longer for incorrect answers than for correct ones, indicating that distractors are not automatic choices. Second, response times increase after instruction for both correct and incorrect answers, supporting the notion that instruction changes students' approach to conceptual questions. Third, response times are inversely related to students' expressed confidence; the lower their confidence, the longer it takes to respond.

  8. Fast Passive Summators for Timing Applications

    Kolojvari, A A; CERN. Geneva; Tsimbal, F A; Tulina, T A; Valiev, F F; Vinogradov, L I; Potapov, S V; Novikov, I A

    1995-01-01

    Our basic present choice for the candidates to the multiplicity counters of ALICE is the Micro Channel Plate based detector (FMD-MCP) [1,2]. The signals from MCP detector are very sharp in time. The signal from a single particle has a leading edge rise time of about 200ps and a width of 1ns.

  9. Stem Cells Matter in Response to Fasting

    Badi Sri Sailaja

    2015-12-01

    Full Text Available The molecular processes underlying intestinal adaptation to fasting and re-feeding remain largely uncharacterized. In this issue of Cell Reports, Richmond et al. report that dormant intestinal stem cells are regulated by PTEN and nutritional status.

  10. Fast Timing for High-Rate Environments with Micromegas

    Papaevangelou, Thomas; Ferrer-Ribas, Esther; Giomataris, Ioannis; Godinot, Cyprien; Diaz, Diego Gonzalez; Gustavsson, Thomas; Kebbiri, Mariam; Oliveri, Eraldo; Resnati, Filippo; Ropelewski, Leszek; Tsiledakis, Georgios; Veenhof, Rob; White, Sebastian

    2016-01-01

    The current state of the art in fast timing resolution for existing experiments is of the order of 100 ps on the time of arrival of both charged particles and electromagnetic showers. Current R&D on charged particle timing is approaching the level of 10 ps but is not primarily directed at sustained performance at high rates and under high radiation (as would be needed for HL-LHC pileup mitigation). We demonstrate a Micromegas based solution to reach this level of performance. The Micromegas acts as a photomultiplier coupled to a Cerenkov-radiator front window, which produces sufficient UV photons to convert the ~100 ps single-photoelectron jitter into a timing response of the order of 10-20 ps per incident charged particle. A prototype has been built in order to demonstrate this performance. The first laboratory tests with a pico-second laser have shown a time resolution of the order of 27 ps for ~50 primary photoelectrons, using a bulk Micromegas readout.

  11. Rugged calorimeter with a fast rise time

    An intrinsic 1-mil-thick gold foil calorimeter has been developed which rises to 95% of the energy deposited in less than 2 microseconds. This calorimeter is very rugged, and can withstand rough handling without damage. The time constant is long, in the millisecond range, because of its unique construction. Use of this calorimeter has produced 100% data recovery, and agreement with true deposition to less than 10%

  12. Response time of internauts

    Johansen, Anders

    2001-07-01

    A new experiment measuring the dynamical response of the Internet population to a “point-like” perturbation has been performed. The nature of the perturbation was that of an announcement, specifically a web-interview on stock market crashes, which contained the URL to the author's articles on the subject. It was established that the download rate obeys the relation ≈1/ t in qualitative agreement with previously reported results.

  13. Fast Context Switching in Real-Time Propositional Reasoning

    Nayak, P. Pandurang; Williams, Brian C.

    1997-01-01

    The trend to increasingly capable and affordable control processors has generated an explosion of embedded real-time gadgets that serve almost every function imaginable. The daunting task of programming these gadgets is greatly alleviated with real-time deductive engines that perform all execution and monitoring functions from a single core model, Fast response times are achieved using an incremental propositional deductive database (an LTMS). Ideally the cost of an LTMS's incremental update should be linear in the number of labels that change between successive contexts. Unfortunately an LTMS can expend a significant percentage of its time working on labels that remain constant between contexts. This is caused by the LTMS's conservative approach: a context switch first removes all consequences of deleted clauses, whether or not those consequences hold in the new context. This paper presents a more aggressive incremental TMS, called the ITMS, that avoids processing a significant number of these consequences that are unchanged. Our empirical evaluation for spacecraft control shows that the overhead of processing unchanged consequences can be reduced by a factor of seven.

  14. A Fast Time-to-Pulse Height Converter

    A fast time-to-pulse height converter representing a development of Green and Bell's gated beam converter is described. The converter is compatible with 2 input pulses in the stop channel and exhibits excellent linearity and time resolution properties. High stability and large output pulses are obtained by using a large time constant in the converting network

  15. The Commensal Real-time ASKAP Fast Transients (CRAFT) survey

    Macquart, Jean-Pierre; Bower, G C; Bunton, J D; Chatterjee, S; Colegate, T; Cordes, J M; D'Addario, L; Deller, A; Dodson, R; Fender, R; Haines, K; Hall, P; Harris, C; Hotan, A; Johnston, S; Jones, D L; Keith, M; Koay, J Y; Lazio, T J W; Majid, W; Murphy, T; Navarro, R; Phillips, C; Quinn, P; Preston, R A; Stansby, B; Stairs, I; Stappers, B; Staveley-Smith, L; Tingay, S; Thompson, D; van Straten, W; Wagstaff, K; Warren, M; Wayth, R; Wen, L

    2010-01-01

    We are developing a purely commensal survey experiment for fast (<5s) transient radio sources. Short-timescale transients are associated with the most energetic and brightest single events in the Universe. Our objective is to cover the enormous volume of transients parameter space made available by ASKAP, with an unprecedented combination of sensitivity and field of view. Fast timescale transients open new vistas on the physics of high brightness temperature emission, extreme states of matter and the physics of strong gravitational fields. In addition, the detection of extragalactic objects affords us an entirely new and extremely sensitive probe on the huge reservoir of baryons present in the IGM. We outline here our approach to the considerable challenge involved in detecting fast transients, particularly the development of hardware fast enough to dedisperse and search the ASKAP data stream at or near real-time rates. Through CRAFT, ASKAP will provide the testbed of many of the key technologies and surve...

  16. On the fast response of spectrometric circuits

    Information capacity of spectrometric circuits obtianed by means of Monte Carlo method modeling is analysed. It is shown that working at high input pulse counting rate is not advisable, dead time of analog-to-digital converter should be compared with the pulse rise time of the amplifier

  17. Analysis of the seismic response of a fast reactor core

    This report deals with the methods to apply for a correct evaluation of the reactor core seismic response. Reference is made to up-to-date design data concerning the PEC core, taking into account the presence of the core-restraint plate located close to the PEC core elements top and applying the optimized iterative procedure between the vessel linear calculation and the non-linear ones limited to the core, which had been described in a previous report. It is demonstrated that the convergence of this procedure is very fast, similar to what obtained in the calculations of the cited report, carried out with preliminary data, and it is shown that the cited methods allow a reliable evaluation of the excitation time histories for the experimental tests in support of the seismic verification of the shutdown system and the core of a fast reactor, as well as relevant data for the experimental, structural and functional, verification of the core elements in the case of seismic loads

  18. Time response measurements of LASL diagnostic detectors

    The measurement and data analysis techniques developed under the Los Alamos Scientific Laboratory's detector improvement program were used to characterize the time and frequency response of selected LASL Compton, fluor-photodiode (NPD), and fluor-photomultiplier (NPM) diagnostic detectors. Data acquisition procedures and analysis methods presently in use are summarized, and detector time and frequency data obtained using the EG and G/AEC electron linear accelerator fast pulse (approximately 50 psec FWHM) as the incident radiation driving function are presented. (U.S.)

  19. Analytical model for a fast-response calorimeter: with applications

    This paper describes the development of an electrical analogue thermal-control model for the ANL-type fast-response calorimeter and its application to a new small sample, analytical-type fast-response calorimeter. This was done to obtain a better understanding of the sources of variations in experimentally measured sample power. Thermal quantities of temperature, heat flow and heat storage were reduced to electrical analogues so that the whole calorimeter could be modeled and analyzed as an electrical circuit with the thermal parts of the calorimeter treated as a series of lumped-circuit constants. Latest results of this work are discussed

  20. Time-resolved fast neutron imaging: simulation of detector performance

    We have analyzed and compared the performance of two novel fast-neutron imaging methods with time-of-flight spectroscopy capability. Key parameters such as detection efficiency, the amount of energy deposited in the converter and the spatial resolution of both detector variants have been simulated by means of neutron and charged-particle transport codes

  1. Time-resolved fast neutron imaging: simulation of detector performance

    Vartsky, D.; Mor, I.; Goldberg, M B; Mardor, I.; Feldman, G.; Bar, D.; A. Shor; Dangendorf, V.; Laczko, G; Breskin, A.; Chechik, R.

    2004-01-01

    We have analyzed and compared the performance of two novel fast-neutron imaging methods with time-of-flight spectroscopy capability. Using MCNP and GEANT code simulations of neutron and charged-particle transport in the detectors, key parameters such as detection efficiency, the amount of energy deposited in the converter and the spatial resolution of both detector variants have been evaluated.

  2. Fast time-resolved aerosol collector: proof of concept

    X.-Y. Yu

    2010-10-01

    Full Text Available Atmospheric particles can be collected in the field on substrates for subsequent laboratory analysis via chemically sensitive single particle methods such as scanning electron microscopy with energy dispersive x-ray analysis. With moving substrates time resolution of seconds to minutes can be achieved. In this paper, we demonstrate how to increase the time resolution when collecting particles on a substrate to a few milliseconds to provide real-time information. Our fast time-resolved aerosol collector ("Fast-TRAC" microscopically observes the particle collection on a substrate and records an on-line video. Particle arrivals are resolved to within a single frame (4–17 ms in this setup, and the spatial locations are matched to the subsequent single particle analysis. This approach also provides in-situ information on particle size and number concentration. Applications are expected in airborne studies of cloud microstructure, pollution plumes, and surface long-term monitoring.

  3. Fast time-resolved aerosol collector: proof of concept

    X.-Y. Yu

    2010-06-01

    Full Text Available Atmospheric particles can be collected in the field on substrates for subsequent laboratory analysis via chemically sensitive single particle methods such as scanning electron microscopy with energy dispersive x-ray analysis. With moving substrates time resolution of seconds to minutes can be achieved. In this paper, we demonstrate how to increase the time resolution when collecting particles on a substrate to a few milliseconds to provide real-time information. Our fast time-resolved aerosol collector ("Fast-TRAC" microscopically observes the particle collection on a substrate and records an on-line video. Particle arrivals are resolved to within a single frame (4–17 ms in this setup, and the spatial locations are matched to the subsequent single particle analysis. This approach also provides in-situ information on particle size and number concentration. Applications are expected in airborne studies of cloud microstructure, pollution plumes, and surface long-term monitoring.

  4. Fast timing study of a CeBr3 crystal: Time resolution below 120 ps at 60Co energies

    Fraile, L. M.; Mach, H.; Vedia, V.; Olaizola, B.; Paziy, V.; Picado, E.; Udías, J. M.

    2013-02-01

    We report on the time response of a novel inorganic scintillator, CeBr3. The measurements were performed using a cylindrical crystal of 1-in. in height and 1-in. in diameter at 22Na and 60Co photon energies. The time response was measured against a fast reference BaF2 detector. Hamamatsu R9779 and Photonis XP20D0 fast photomultipliers (PMTs) were used. The PMT bias voltages and Constant Fraction Discriminator settings were optimized with respect to the timing resolution. The Full Width at Half Maximum (FWHM) time resolution for an individual CeBr3 crystal coupled to Hamamatsu PMT is found here to be as low as 119 ps at 60Co energies, which is comparable to the resolution of 107 ps reported for LaBr3(Ce). For 511 keV photons the measured FWHM time resolution for CeBr3 coupled to the Hamamatsu PMT is 164 ps.

  5. Fast timing study of a CeBr3 crystal: Time resolution below 120 ps at 60Co energies

    We report on the time response of a novel inorganic scintillator, CeBr3. The measurements were performed using a cylindrical crystal of 1-in. in height and 1-in. in diameter at 22Na and 60Co photon energies. The time response was measured against a fast reference BaF2 detector. Hamamatsu R9779 and Photonis XP20D0 fast photomultipliers (PMTs) were used. The PMT bias voltages and Constant Fraction Discriminator settings were optimized with respect to the timing resolution. The Full Width at Half Maximum (FWHM) time resolution for an individual CeBr3 crystal coupled to Hamamatsu PMT is found here to be as low as 119 ps at 60Co energies, which is comparable to the resolution of 107 ps reported for LaBr3(Ce). For 511 keV photons the measured FWHM time resolution for CeBr3 coupled to the Hamamatsu PMT is 164 ps.

  6. REAL TIME FACE RECOGNITION USING ADABOOST IMPROVED FAST PCA ALGORITHM

    K. Susheel Kumar

    2011-08-01

    Full Text Available This paper presents an automated system for human face recognition in a real time background world fora large homemade dataset of persons face. The task is very difficult as the real time backgroundsubtraction in an image is still a challenge. Addition to this there is a huge variation in human face imagein terms of size, pose and expression. The system proposed collapses most of this variance. To detect realtime human face AdaBoost with Haar cascade is used and a simple fast PCA and LDA is used torecognize the faces detected. The matched face is then used to mark attendance in the laboratory, in ourcase. This biometric system is a real time attendance system based on the human face recognition with asimple and fast algorithms and gaining a high accuracy rate..

  7. Test and calibration of the IDS fast-timing electronics

    AUTHOR|(CDS)2160817

    2016-01-01

    The ISOLDE decay station(IDS) is one of the permanent experimental setups at the ISOLDE facility of CERN. IDS is used to study decay properties of radioactive nuclei. Thus, fast-timing electronics are necessary for extracting nuclear half-lives. The aims of this work are testing and optimization of the IDS fast-timing electronics as well as measuring a nuclear level half-life in the decay of $^{152}$Eu. The energy resolution of LaBr$_3$ $\\gamma$-detectors was characterized and optimized. A nuclear level lifetime of $^{152}$Eu was measured after obtaining the best parameters for energy resolution and time walk. Dedicated sorting scripts were developed in ROOT in order of perform the characterization and optimization automatically.

  8. Fast and Slow Transient Response of WECS with Simultaneous Actions

    M.Amarendra; Srikanth, S; G. Siva Suteja; B. Prasanna Lakshmi; K.Madhavi Latha

    2012-01-01

    This paper details the transient operation of a wind energy conversion system (WECS) used simultaneously as an ac- tive filter and power generator. This study is intended to address the system response to two types of transient phenomena: voltage dips (fast transients) and wind speed variations (slow transients). The system response to voltage dips is governed by the electrical system dynamics and control method and results in the evaluation of the WECS low-voltage ride through capability. Th...

  9. Real‑time, fast neutron detection for stimulated safeguards assay

    The advent of low‑hazard organic liquid scintillation detectors and real‑time pulse‑shape discrimination (PSD) processing has suggested a variety of modalities by which fast neutrons, as opposed to neutrons moderated prior to detection, can be used directly to benefit safeguards needs. In this paper we describe a development of a fast‑neutron based safeguards assay system designed for the assessment of 235U content in fresh fuel. The system benefits from real‑time pulse‑shape discrimination processing and auto‑calibration of the detector system parameters to ensure a rapid and effective set‑up protocol. These requirements are essential in optimising the speed and limit of detection of the fast neutron technique, whilst minimising the intervention needed to perform the assay.

  10. Fast sensors for time-of-flight imaging applications.

    Vallance, Claire; Brouard, Mark; Lauer, Alexandra; Slater, Craig S; Halford, Edward; Winter, Benjamin; King, Simon J; Lee, Jason W L; Pooley, Daniel E; Sedgwick, Iain; Turchetta, Renato; Nomerotski, Andrei; John, Jaya John; Hill, Laura

    2014-01-14

    The development of sensors capable of detecting particles and radiation with both high time and high positional resolution is key to improving our understanding in many areas of science. Example applications of such sensors range from fundamental scattering studies of chemical reaction mechanisms through to imaging mass spectrometry of surfaces, neutron scattering studies aimed at probing the structure of materials, and time-resolved fluorescence measurements to elucidate the structure and function of biomolecules. In addition to improved throughput resulting from parallelisation of data collection - imaging of multiple different fragments in velocity-map imaging studies, for example - fast image sensors also offer a number of fundamentally new capabilities in areas such as coincidence detection. In this Perspective, we review recent developments in fast image sensor technology, provide examples of their implementation in a range of different experimental contexts, and discuss potential future developments and applications. PMID:24002354

  11. Fast combination of scheduling chains under resource and time constraints

    WANG Ji-min; PAN Xue-zeng; WANG Jie-bing; SUN Kang

    2007-01-01

    Scheduling chain combination is the core of chain-based scheduling algorithms, the speed of which determines the overall performance of corresponding scheduling algorithm. However, backtracking is used in general combination algorithms to traverse the whole search space which may introduce redundant operations, so performance of the combination algorithm is generally poor. A fast scheduling chain combination algorithm which avoids redundant operations by skipping "incompatible"steps of scheduling chains and using a stack to remember the scheduling state is presented in this paper to overcome the problem.Experimental results showed that it can improve the performance of scheduling algorithms by up to 15 times. By further omitting unnecessary operations, a fast algorithm of minimum combination length prediction is developed, which can improve the speed by up to 10 times.

  12. Afterpulses and decay times of fast scintillation counters for extensive air shower experiments

    A fast scintillation counter system to observe the arrival time distribution of relativistic particles in extensive air showers has been developed. The generation rate of afterpulses observed by a ternary plastic scintillation counter of a fast-time-response photomultiplier were studied in detail. It was found that the effect of afterpulses generated in the photomultiplier and scintillation process was negligibly small compared with that of afterpulses produced by delayed particles in the shower. It was also found that long decay components in the scintillator output can be explained as being due to afterpulses. (orig.)

  13. The Value of Fast Fashion: Quick Response, Enhanced Design, and Strategic Consumer Behavior

    Cachon, Gérard P.; Robert Swinney

    2011-01-01

    A fast fashion system combines quick response production capabilities with enhanced product design capabilities to both design "hot" products that capture the latest consumer trends and exploit minimal production lead times to match supply with uncertain demand. We develop a model of such a system and compare its performance to three alternative systems: quick-response-only systems, enhanced-design-only systems, and traditional systems (which lack both enhanced design and quick response capab...

  14. Fluctuation-Response Relation and modeling in systems with fast and slow dynamics

    G. Lacorata

    2007-10-01

    Full Text Available We show how a general formulation of the Fluctuation-Response Relation is able to describe in detail the connection between response properties to external perturbations and spontaneous fluctuations in systems with fast and slow variables. The method is tested by using the 360-variable Lorenz-96 model, where slow and fast variables are coupled to one another with reciprocal feedback, and a simplified low dimensional system. In the Fluctuation-Response context, the influence of the fast dynamics on the slow dynamics relies in a non trivial behavior of a suitable quadratic response function. This has important consequences for the modeling of the slow dynamics in terms of a Langevin equation: beyond a certain intrinsic time interval even the optimal model can give just statistical prediction.

  15. Fast timing and trigger Cherenkov detector for collider experiments

    Grigoryev, V. A.; Kaplin, V. A.; Karavicheva, T.L.; Konevskikh, A. S.; Kurepin, A. B.; Loginov, V. A.; Melikyan, A.; Morozov, I. V.; Reshetin, A. I.; Serebryakov, D. V.; Shabanov, A. I.; Slupecki, Maciej; Trzaska, Wladyslaw; Tykmanov, E. M.

    2016-01-01

    Analysis of fast timing and trigger Cherenkov detector’s design for its use in collider experiments is presented. Several specific requirements are taken into account – necessity of the radiator’s placement as close to the beam pipe as possible along with the requirement of gapless (solid) radiator’s design. Characteristics of the Cherenkov detector’s laboratory prototype obtained using a pion beam at the CERN Proton Synchrotron are also presented, showing the possibility of ob...

  16. Fast time variations of supernova neutrino fluxes and their detectability

    Lund, Tina; Marek, Andreas; Lunardini, Cecilia; Janka, Hans-Thomas; Raffelt, Georg

    2010-01-01

    In the delayed explosion scenario of core-collapse supernovae (SNe), the accretion phase shows pronounced convective overturns and a low-multipole hydrodynamic instability, the standing accretion shock instability (SASI). These effects imprint detectable fast time variations on the emerging neutrino flux. Among existing detectors, IceCube is best suited to this task, providing an event rate of ~1000 events per ms during the accretion phase for a fiducial SN distance of 10 kpc, comparable to w...

  17. Attractors of relaxation discrete-time systems with chaotic dynamics on a fast time scale

    Maslennikov, Oleg V.; Nekorkin, Vladimir I.

    2016-07-01

    In this work, a new type of relaxation systems is considered. Their prominent feature is that they comprise two distinct epochs, one is slow regular motion and another is fast chaotic motion. Unlike traditionally studied slow-fast systems that have smooth manifolds of slow motions in the phase space and fast trajectories between them, in this new type one observes, apart the same geometric objects, areas of transient chaos. Alternating periods of slow regular motions and fast chaotic ones as well as transitions between them result in a specific chaotic attractor with chaos on a fast time scale. We formulate basic properties of such attractors in the framework of discrete-time systems and consider several examples. Finally, we provide an important application of such systems, the neuronal electrical activity in the form of chaotic spike-burst oscillations.

  18. Fast fall-time ion beam in neutron generators

    Ji, Q.; Kwan, J.; Regis, M.; Wu, Y.; Wilde, S.B.; Wallig, J.

    2008-08-10

    Ion beam with a fast fall time is useful in building neutron generators for the application of detecting hidden, gamma-shielded SNM using differential die-away (DDA) technique. Typically a fall time of less than 1 {micro}s can't be achieved by just turning off the power to the ion source due to the slow decay of plasma density (partly determined by the fall time of the RF power in the circuit). In this paper, we discuss the method of using an array of mini-apertures (instead of one large aperture beam) such that gating the beamlets can be done with low voltage and a small gap. This geometry minimizes the problem of voltage breakdown as well as reducing the time of flight to produce fast gating. We have designed and fabricated an array of 16 apertures (4 x 4) for a beam extraction experiment. Using a gating voltage of 1400 V and a gap distance of 1 mm, the fall time of extracted ion beam pulses is less than 1 {micro}s at various beam energies ranging between 400 eV to 800 eV. Usually merging an array of beamlets suffers the loss of beam brightness, i.e., emittance growth, but that is not an important issue for neutron source applications.

  19. The Impact of Maternal Smoking on Fast Auditory Brainstem Responses

    Kable, Julie A.; Coles, Claire D.; Lynch, Mary Ellen; Carroll, Julie

    2009-01-01

    Deficits in auditory processing have been posited as one of the underlying neurodevelopmental consequences of maternal smoking during pregnancy that leads to later language and reading deficits. Fast auditory brainstem responses were used to assess differences in the sensory processing of auditory stimuli among infants with varying degrees of prenatal cigarette exposure. Maternal report of consumption of cigarettes and blood samples were collected in the hospital to assess exposure levels and...

  20. Fast-Response Liquid Crystal Lens Doped with Multi-Walled Carbon Nanotubes

    Hui LI

    2016-05-01

    Full Text Available In this paper, a relatively fast-response liquid crystal (LC lens was proposed, which was fabricated by a simple method. Multi-walled carbon nanotubes (MWCNTs were utilized in fabricating the LC lens. As MWCNTs were doped into the LCs, the dielectric anisotropy of the mixture changed, which was the key factor in solving the technical barrier of slow response time. In experiments, the effects of doping with MWCNTs were demonstrated. The concentration of doped MWCNTs was discussed in detail, and the best concentration and doping method were analyzed. The relationship between the concentration and response time was also obtained. This LC lens had a sub-millisecond response time, which was a relatively fast response time in comparison to conventional LC lenses of pristine LCs. Thus, this proposed method could be considered as a new method to realize fast-response LC lens.DOI: http://dx.doi.org/10.5755/j01.ms.22.2.12913

  1. Fast cortical keypoints for real-time object recognition

    Tersic, K.; Rodrigues, J. M. F.; du Buf, J. M. H.

    2013-01-01

    Best-performing object recognition algorithms employ a large number features extracted on a dense grid, so they are too slow for real-time and active vision. In this paper we present a fast cortical keypoint detector for extracting meaningful points from images. It is competitive with state-of-the-art detectors and particularly well-suited for tasks such as object recognition. We show that by using these points we can achieve state-of-the-art categorization results in a fraction of t...

  2. Time resolved measurement of FEL micropulses using fast THz detectors

    Radiation at 70 μm wavelength generated with the THz-FEL at the Institute of Scientific and Industrial Research (ISIR), Osaka University was measured using two fast THz detectors ; one with pyroelectric sensor and the other Schottky diode detector. Time resolution of both detectors is high enough to separately measure FEL micropulse at interval of 9.2 ns, which consists of four families of independent FEL micropulses. The dynamic range of both detectors is measured at 70 μm wavelength; one of pyroelectric sensor is 3 mV or less, and V-I characteristic is appeared in output signal from Schottky diode detector. Schottky diode detector is calibrated using pyroelectric sensor, and was used for measurement of the time evolution of detuning curve. It was observed that periodic time structure arises in FEL macropulse with change of resonator length. (author)

  3. Brownian motion at fast time scales and thermal noise imaging

    Huang, Rongxin

    This dissertation presents experimental studies on Brownian motion at fast time scales, as well as our recent developments in Thermal Noise Imaging which uses thermal motions of microscopic particles for spatial imaging. As thermal motions become increasingly important in the studies of soft condensed matters, the study of Brownian motion is not only of fundamental scientific interest but also has practical applications. Optical tweezers with a fast position-sensitive detector provide high spatial and temporal resolution to study Brownian motion at fast time scales. A novel high bandwidth detector was developed with a temporal resolution of 30 ns and a spatial resolution of 1 A. With this high bandwidth detector, Brownian motion of a single particle confined in an optical trap was observed at the time scale of the ballistic regime. The hydrodynamic memory effect was fully studied with polystyrene particles of different sizes. We found that the mean square displacements of different sized polystyrene particles collapse into one master curve which is determined by the characteristic time scale of the fluid inertia effect. The particle's inertia effect was shown for particles of the same size but different densities. For the first time the velocity autocorrelation function for a single particle was shown. We found excellent agreement between our experiments and the hydrodynamic theories that take into account the fluid inertia effect. Brownian motion of a colloidal particle can be used to probe three-dimensional nano structures. This so-called thermal noise imaging (TNI) has been very successful in imaging polymer networks with a resolution of 10 nm. However, TNI is not efficient at micrometer scale scanning since a great portion of image acquisition time is wasted on large vacant volume within polymer networks. Therefore, we invented a method to improve the efficiency of large scale scanning by combining traditional point-to-point scanning to explore large vacant

  4. Response of reverse convection to fast IMF transitions

    Taguchi, S.; Tawara, A.; Hairston, M. R.;

    2015-01-01

    The nature of the transition that high-latitude reverse convection makes in response to fast interplanetary magnetic field (IMF) changes is investigated using observations from multiple spacecraft and a ground magnetometer array. We focused on two fast IMF-transition events on 22 April 2006....... Immediately after the first event, three ST5 spacecraft identified a clear change in the distribution of the polar cap field-aligned current. Coordinate observations with the Greenland magnetometer chain showed that the near-noon Hall current distribution, which is closely related to the polar cap field......-aligned current or reverse convection, was in a transition state for about 10 min. For the second event, the Greenland magnetic perturbations also showed that a transition state occurred in the near-noon sector for 10-15 min. Three DMSP spacecraft that traversed the polar cap provided evidence showing that...

  5. Modeling and Analysis of the Role of Fast-Response Energy Storage in the Smart Grid

    Su, Han-I

    2011-01-01

    The large short time-scale variability of renewable energy resources presents significant challenges to the reliable operation of power systems. This variability can be mitigated by deploying fast-ramping generators. However, these generators are costly to operate and produce environmentally harmful emissions. Fast-response energy storage devices, such as batteries and flywheels, provide an environmentally friendly alternative, but are expensive and have limited capacity. To study the environmental benefits of storage, we introduce a slotted-time dynamic residual dc power flow model with the prediction error of the difference between the generation (including renewables) and the load as input and the fast-ramping generation and the storage (charging/discharging) operation as the control variables used to ensure that the demand is satisfied (as much as possible) in each time slot. We assume the input prediction error sequence to be i.i.d. zero-mean random variables. The optimal power flow problem is then formu...

  6. Fast and accurate calculations for cumulative first-passage time distributions in Wiener diffusion models

    Blurton, Steven Paul; Kesselmeier, M.; Gondan, Matthias

    2012-01-01

    We propose an improved method for calculating the cumulative first-passage time distribution in Wiener diffusion models with two absorbing barriers. This distribution function is frequently used to describe responses and error probabilities in choice reaction time tasks. The present work extends...... related work on the density of first-passage times [Navarro, D.J., Fuss, I.G. (2009). Fast and accurate calculations for first-passage times in Wiener diffusion models. Journal of Mathematical Psychology, 53, 222-230]. Two representations exist for the distribution, both including infinite series. We...

  7. Fast response neutron scintillation detector for FIRE-X

    We have been developing fast responding neutron detectors with a view to revealing the effect of additional laser heating in FIREX-I (Fast Ignition Realization Experiment) by measuring the burn time with a time resolution under 100 ps at the relatively low neutron yield (about 106). The detector is constructed with a thin plastic-scintillaotor (BC-422), a micro-channel-plate photomultiplier tube (MCP-PMT) and a bundle optical fiber as a light-guide. The rise time of a neutron signal from the detector is measured to be 220 ps. The time-determination error for measuring burn time is estimated to be less than ± 46 ps from the data of characterization experiments measuring the transit time distribution of signals, and calculated values of Doppler broadening and the uncertainty of the scintillation time due to the thickness of the scintillator. In the future with more neutron yield, we will construct a scintillation-fiber-streak camera to detect burn history

  8. Fast Nonparametric Clustering of Structured Time-Series.

    Hensman, James; Rattray, Magnus; Lawrence, Neil D

    2015-02-01

    In this publication, we combine two Bayesian nonparametric models: the Gaussian Process (GP) and the Dirichlet Process (DP). Our innovation in the GP model is to introduce a variation on the GP prior which enables us to model structured time-series data, i.e., data containing groups where we wish to model inter- and intra-group variability. Our innovation in the DP model is an implementation of a new fast collapsed variational inference procedure which enables us to optimize our variational approximation significantly faster than standard VB approaches. In a biological time series application we show how our model better captures salient features of the data, leading to better consistency with existing biological classifications, while the associated inference algorithm provides a significant speed-up over EM-based variational inference. PMID:26353249

  9. A novel fast timing micropattern gaseous detector: FTM

    De Oliveira, Rui; Sharma, Archana

    2015-01-01

    In recent years important progress in micropattern gaseous detectors has been achieved in the use of resistive material to build compact spark-protected devices. The novel idea presented here consists of the polarisation of WELL structures using only resistive coating. This allows a new device to be built with an architecture based on a stack of several coupled layers where drift and WELL multiplication stages alternate in the structure. The signals from each multiplication stage can be read out from any external readout boards through the capacitive couplings. Each layer provides a signal with a gain of 10^4-10^5. The main advantage of this new device is the dramatic improvement of the timing provided by the competition of the ionisation processes in the different drift regions, which can be exploited for fast timing at the high luminosity accelerators (e.g. HL-LHC upgrade) as well as far applications like medical imaging.

  10. A novel fast timing micropattern gaseous detector: FTM

    De Oliveira, Rui; Maggi, Marcello

    2015-01-01

    In recent years important progress in micropattern gaseous detectors has been achieved in the use of resistive material to build compact spark-protected devices. The novel idea presented here consists of the polarisation of WELL structures using only resistive electrodes. This allows a new device to be built with an architecture based on a stack of several coupled layers where drift and WELL multiplication stages alternate in the structure. The signals from each multiplication stage can be read out from any external readout boards through the capacitive couplings. Each layer provides a signal with a gain of 10^4 - 10^5. The main advantage of this new device is the dramatic improvement of the timing provided by the competition of the ionisation processes in the different drift regions, which can be exploited for fast timing at the high luminosity accelerators (e.g. HL-LHC upgrade) as well as applications outside particle physics.

  11. Fast-track for fast times: catching and keeping generation Y in the nursing workforce.

    Walker, Kim

    2007-04-01

    There is little doubt we find ourselves in challenging times as never before has there been such generational diversity in the nursing workforce. Currently, nurses from four distinct (and now well recognised and discussed) generational groups jostle for primacy of recognition and reward. Equally significant is the acute realisation that our ageing profession must find ways to sustain itself in the wake of huge attrition as the 'baby boomer' nurses start retiring over the next ten to fifteen years. These realities impel us to become ever more strategic in our thinking about how best to manage the workforce of the future. This paper presents two exciting and original innovations currently in train at one of Australia's leading Catholic health care providers: firstly, a new fast-track bachelor of nursing program for fee-paying domestic students. This is a collaborative venture between St Vincent's and Mater Health, Sydney (SV&MHS) and the University of Tasmania (UTas); as far as we know, it is unprecedented in Australia. As well, the two private facilities of SV&MHS, St Vincent's Private (SVPH) and the Mater Hospitals, have developed and implemented a unique 'accelerated progression pathway' (APP) to enable registered nurses with talent and ambition to fast track their career through a competency and merit based system of performance management and reward. Both these initiatives are aimed squarely at the gen Y demographic and provide potential to significantly augment our capacity to recruit and retain quality people well into the future. PMID:17563323

  12. Fast responsive, optical trace level ammonia sensor for environmental monitoring

    Abel Tobias; Ungerböck Birgit; Klimant Ingo; Mayr Torsten

    2012-01-01

    Abstract Background Ammonia is a ubiquitous chemical substance which is created in technical and biological processes and harmful to many different organisms. One specific problem is the toxicity of ammonia in fish at levels of 25 μg/l - a very common issue in today’s aqua culture. In this study we report a development of a fast responsive, optical ammonia sensor for trace concentrations. Results Different hydrogels have been investigated as host polymers for a pH based sensing mechanism base...

  13. Fast response and recovery of hydrogen sensing in Pd-Pt nanoparticle-graphene composite layers

    Kumar, Rakesh; Varandani, Deepak; Mehta, B R; Singh, V N [Thin Film Laboratory, Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India); Wen Zhenhai; Feng Xinliang; Muellen, Klaus, E-mail: brmehta@physics.iitd.ernet.in [Max-Planck Institute for Polymer Research, D-55128 Mainz (Germany)

    2011-07-08

    This study reports the fast response and recovery of hydrogen sensing in nanoparticle-graphene composite layers fabricated using chemical methods and comprising of isolated Pd alloy nanoparticles dispersed onto graphene layers. For 2% hydrogen at 40 {sup 0}C and 1 atm pressure, a response time of < 2 s and a recovery time of 18 s are observed. The fast response and recovery observed during sensing are due to hydrogen-induced changes in the work function of the Pd alloy and modification in the distribution of defect states in the graphene band gap due to gas adsorption. The results of hydrogen sensing in the new class of Pd-Pt nanoparticle-graphene composite material are important for understanding the effect of gas adsorption on electronic conduction in graphene layers and for developing a new type of gas sensor based on changes in the electronic properties of the interface.

  14. Equipment for fast neutron time-of-flight experiments

    A 3-MeV-pulsed Van de Graaff has been built for this laboratory by the High Voltage Engineering Corporation of Boston, United States of America. It is designed to give pulses of 1 ns duration at a repetition frequency of 1 MHz and a current in the pulse of 10 mA. This machine is to be used for fast neutron spectroscopy and a system of electronics for this purpose has been devised. The system is intended to record time intervals up to 1μs with a resolution of ∼3 ns. The timing cycle is started by a start pulse from the neutron detector. The stop pulse is derived from the beam, and delayed by 1μs. The start and stop pulses are fed to a time expander which expands the time interval between the pulses by a factor of ∼250. The expanded time interval is then recorded in digital form on 16-track magnetic tape. (author)

  15. Digitally Controlled Point of Load Converter with Very Fast Transient Response

    Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.

    2007-01-01

    voltage mode control and very fast transient response. The DiSOM modulator is combined with a digital PID compensator algorithm is implemented in a hybrid CPLD/FPGA and is used to control a synchronous Buck converter, which is used in typical Point of Load applications. The computational time is only...... comparator the DiSOM modulator allows the sampling frequency of the output voltage control loop to be higher than the switching frequency of the power converter, typically a DC/DC converter. The features of the DiSOM modulator makes it possible to design a digitally controlled DC/DC converter with linear...... three clock cycles from the time the A/D converter result is read by the control algorithm to the time the duty cycle command is updated. A typical POL converter has been built and the experimental results show that the transient response of the converter is very fast. The output voltage overshoot is...

  16. A fast preamplifier concept for SiPM-based time-of-flight PET detectors

    Huizenga, J.; Seifert, S.; Schreuder, F.; van Dam, H. T.; Dendooven, P.; Löhner, H.; Vinke, R.; Schaart, D. R.

    2012-12-01

    Silicon photomultipliers (SiPMs) offer high gain and fast response to light, making them interesting for fast timing applications such as time-of-flight (TOF) PET. To fully exploit the potential of these photosensors, dedicated preamplifiers that do not deteriorate the rise time and signal-to-noise ratio are crucial. Challenges include the high sensor capacitance, typically >300 pF for a 3 mm×3 mm SiPM sensor, as well as oscillation issues. Here we present a preamplifier concept based on low noise, high speed transistors, designed for optimum timing performance. The input stage consists of a transimpedance common-base amplifier with a very low input impedance even at high frequencies, which assures a good linearity and avoids that the high detector capacitance affects the amplifier bandwidth. The amplifier has a fast timing output as well as a 'slow' energy output optimized for determining the total charge content of the pulse. The rise time of the amplifier is about 300 ps. The measured coincidence resolving time (CRT) for 511 keV photon pairs using the amplifiers in combination with 3 mm×3 mm SiPMs (Hamamatsu MPPC-S10362-33-050C) coupled to 3 mm×3 mm×5 mm LaBr3:Ce and LYSO:Ce crystals equals 95 ps FWHM and 138 ps FWHM, respectively.

  17. A fast preamplifier concept for SiPM-based time-of-flight PET detectors

    Silicon photomultipliers (SiPMs) offer high gain and fast response to light, making them interesting for fast timing applications such as time-of-flight (TOF) PET. To fully exploit the potential of these photosensors, dedicated preamplifiers that do not deteriorate the rise time and signal-to-noise ratio are crucial. Challenges include the high sensor capacitance, typically >300 pF for a 3 mm×3 mm SiPM sensor, as well as oscillation issues. Here we present a preamplifier concept based on low noise, high speed transistors, designed for optimum timing performance. The input stage consists of a transimpedance common-base amplifier with a very low input impedance even at high frequencies, which assures a good linearity and avoids that the high detector capacitance affects the amplifier bandwidth. The amplifier has a fast timing output as well as a ‘slow’ energy output optimized for determining the total charge content of the pulse. The rise time of the amplifier is about 300 ps. The measured coincidence resolving time (CRT) for 511 keV photon pairs using the amplifiers in combination with 3 mm×3 mm SiPMs (Hamamatsu MPPC-S10362-33-050C) coupled to 3 mm×3 mm×5 mm LaBr3:Ce and LYSO:Ce crystals equals 95 ps FWHM and 138 ps FWHM, respectively.

  18. Fast, Linear Time Hierarchical Clustering using the Baire Metric

    Contreras, Pedro

    2011-01-01

    The Baire metric induces an ultrametric on a dataset and is of linear computational complexity, contrasted with the standard quadratic time agglomerative hierarchical clustering algorithm. In this work we evaluate empirically this new approach to hierarchical clustering. We compare hierarchical clustering based on the Baire metric with (i) agglomerative hierarchical clustering, in terms of algorithm properties; (ii) generalized ultrametrics, in terms of definition; and (iii) fast clustering through k-means partititioning, in terms of quality of results. For the latter, we carry out an in depth astronomical study. We apply the Baire distance to spectrometric and photometric redshifts from the Sloan Digital Sky Survey using, in this work, about half a million astronomical objects. We want to know how well the (more costly to determine) spectrometric redshifts can predict the (more easily obtained) photometric redshifts, i.e. we seek to regress the spectrometric on the photometric redshifts, and we use clusterwi...

  19. Effect of gadolinium covers on fast dosimeter response

    Gadolinium (Gd) has been used extensively at B and W Nuclear Technologies (BWNT) as a dosimetry shielding material for several years. Gadolinium has a significant cross section throughout the energy range of interest (i.e. above 1 MeV) in vessel fluence calculations. While Gd has a number of advantages as a dosimetry cover, it also has the potential for introducing a bias of unknown magnitude into the measured activities of covered fast response dosimeters such as U238 and iron. The Gd cover causes a reduction in the measured dosimeter activity, which means that the calculated fluxes normalized to those activities would be under-predicted. This is, of course, in the non-conservative direction. Since dosimeter covers are generally not included in the typical transport analysis model, corrections for this effect are not generally made. The calculated activities would not include the effects of the Gd while, of course, the measured activities would. The resulting calculation to measurement ratios, (C/M), which are used to remove biases in the calculated fluxes, would therefore be in error, in the non-conservative direction, by some undetermined amount. This study has determined the magnitude of the bias in the fast response dosimeters, U238 and iron caused by the absorption of fast (E > 1.0 MeV) neutrons in 2 mm (0.002 m) Gd covers. The results indicate that the bias is in the 2.9--3.4% range and that it is only a weak function of dosimeter material

  20. Fast responsive, optical trace level ammonia sensor for environmental monitoring

    Abel Tobias

    2012-10-01

    Full Text Available Abstract Background Ammonia is a ubiquitous chemical substance which is created in technical and biological processes and harmful to many different organisms. One specific problem is the toxicity of ammonia in fish at levels of 25 μg/l - a very common issue in today’s aqua culture. In this study we report a development of a fast responsive, optical ammonia sensor for trace concentrations. Results Different hydrogels have been investigated as host polymers for a pH based sensing mechanism based on fluorescent dyes. A porous hydrophobic fluoropolymer membrane was used as an ion barrier cover layer to achieve a good ammonia permeability. The sensor’s sensitivity towards ammonia as well as crosssensitivity towards pH-value and salinity, and the temperature dependency have been determined. Two different methods to reference fluorescence signals have been employed to eliminate intensity-based measurement drawbacks. Conclusion The presented sensor features high sensitivity and a fast response even at concentrations near 1 ppb. No cross sensitivity towards pH and salinity could be observed and temperature dependency was determined as compensateable. Both referencing approaches prove themselves to be able to provide a simple use of the sensor for in-field applications.

  1. Polylactide-based polyurethane shape memory nanocomposites (Fe3O4/PLAUs) with fast magnetic responsiveness

    Gu, Shu-Ying; Jin, Sheng-Peng; Gao, Xie-Feng; Mu, Jian

    2016-05-01

    Polylactide-based polyurethane shape memory nanocomposites (Fe3O4/PLAUs) with fast magnetic responsiveness are presented. For the purpose of fast response and homogeneous dispersion of magnetic nanoparticles, oleic acid was used to improve the dispersibility of Fe3O4 nanoparticles in a polymer matrix. A homogeneous distribution of Fe3O4 nanoparticles in the polymer matrix was obtained for nanocomposites with low Fe3O4 loading content. A small agglomeration was observed for nanocomposites with 6 wt% and 9 wt% loading content, leading to a small decline in the mechanical properties. PLAU and its nanocomposites have glass transition around 52 °C, which can be used as the triggering temperature. PLAU and its nanocomposites have shape fixity ratios above 99%, shape recovery ratios above 82% for the first cycle and shape recovery ratios above 91% for the second cycle. PLAU and its nanocomposites also exhibit a fast water bath or magnetic responsiveness. The magnetic recovery time decreases with an increase in the loading content of Fe3O4 nanoparticles due to an improvement in heating performance for increased weight percentage of fillers. The nanocomposites have fast responses in an alternating magnetic field and have potential application in biomedical areas such as intravascular stent.

  2. Acute metabolic response to fasted and postprandial exercise

    Lima FD

    2015-08-01

    Full Text Available Filipe Dinato de Lima,1,2 Ana Luiza Matias Correia,1 Denilson da Silva Teixeira,2 Domingos Vasco da Silva Neto,2 Ítalo Sávio Gonçalves Fernandes,2 Mário Boratto Xavier Viana,2 Mateus Petitto,2 Rodney Antônio da Silva Sampaio,2 Sandro Nobre Chaves,2 Simone Teixeira Alves,2 Renata Aparecida Elias Dantas,2 Márcio Rabelo Mota2 1University of Brasília, Brasília, DF, Brazil; 2Universitary Center of Brasília (UniCEUB, Brasília, DF, BrazilAbstract: The aim of this study was to analyze the acute metabolic response to exercise in fasting and postprandial. For this, ten individuals were submitted to an incremental treadmill test, with an initial speed of 5 and 1 km/h increments every minute, with no inclination, and a body composition assessment. After this 1st day, all volunteers were submitted to two experimental procedures (fasting and postprandial, with an aerobic exercise performed for 36 minutes at 65% of maximal oxygen consumption. At postprandial procedure, all subjects ingested a breakfast containing 59.3 g of carbohydrate (76.73%, 9.97 g of protein (12.90%, 8.01 g of lipids (10.37%, with a total energy intake of 349.17 kcal. An analysis of plasma concentration of triglycerides, lactate, and glucose was performed in two stages: before and after exercise. The Shapiro–Wilk test was used to verify the normality of the data. For analysis of glucose concentration, plasma lactate, and triglycerides, we used a repeated measures analysis of variance factorial 2×2, with Bonferroni multiple comparison test. The significance level of P<0.05 was adopted. The results indicated a maintenance level of glucose at fasting and a decrease in glucose concentration at postprandial exercise. Both conditions increase plasma lactate. Triglycerides also increased in the two experimental conditions; however, after exercise fasting, the increase was significantly higher than in the postprandial exercise. These data suggest that both exercises could increase

  3. On fast and slow times in models with diffusion

    De Angelis, M; Renno, P

    2012-01-01

    The linear Kelvin{Voigt operator L_\\epsilon is a typical example of wave operator L_0 perturbed by higher-order viscous terms as \\epsilonu_xxt. If P\\epsilon is a prefixed boundary value problem for L_\\epsilon, when \\epsilon = 0, L_\\epsilon turns into L_0 and P_\\epsilon into a problem P_0 with the same initial{boundary conditions of P\\epsilon. Boundary layers are missing and the related control terms depending on the fast time are negligible. In a small time interval, the wave behavior is a realistic approximation of u_\\epsilon when \\epsilon \\rightarrow 0. On the contrary, when t is large, diffusion effects should prevail and the behavior of u_\\epsilon for \\epsilon \\rightarrow 0 and t \\rightarrow 1 should be analyzed. For this, a suitable functional correspondence between the Green functions G_\\epsilon and G_0 of P_epsilon and P_0 is derived and its asymptotic behavior is rigorously examined. As a consequence, the interaction between diffusion effects and pure waves is evaluated by means of the slow time \\epsi...

  4. Bubble masks for time-encoded imaging of fast neutrons.

    Brubaker, Erik; Brennan, James S.; Marleau, Peter; Nowack, Aaron B.; Steele, John; Sweany, Melinda; Throckmorton, Daniel J.

    2013-09-01

    Time-encoded imaging is an approach to directional radiation detection that is being developed at SNL with a focus on fast neutron directional detection. In this technique, a time modulation of a detected neutron signal is induced-typically, a moving mask that attenuates neutrons with a time structure that depends on the source position. An important challenge in time-encoded imaging is to develop high-resolution two-dimensional imaging capabilities; building a mechanically moving high-resolution mask presents challenges both theoretical and technical. We have investigated an alternative to mechanical masks that replaces the solid mask with a liquid such as mineral oil. Instead of fixed blocks of solid material that move in pre-defined patterns, the oil is contained in tubing structures, and carefully introduced air gaps-bubbles-propagate through the tubing, generating moving patterns of oil mask elements and air apertures. Compared to current moving-mask techniques, the bubble mask is simple, since mechanical motion is replaced by gravity-driven bubble propagation; it is flexible, since arbitrary bubble patterns can be generated by a software-controlled valve actuator; and it is potentially high performance, since the tubing and bubble size can be tuned for high-resolution imaging requirements. We have built and tested various single-tube mask elements, and will present results on bubble introduction and propagation as a function of tubing size and cross-sectional shape; real-time bubble position tracking; neutron source imaging tests; and reconstruction techniques demonstrated on simple test data as well as a simulated full detector system.

  5. Measurements of timing resolution of ultra-fast silicon detectors with the SAMPIC WTDC

    Breton, Dominique; Delagnes, Éric; Grabas, Hervé; Maalmi, Jihane; Minafra, Nicola; Royon, Christophe; Saimpert, Matthias

    2016-01-01

    The SAMpler for PICosecond time (SAMPIC) chip has been designed by a collaboration including CEA/IRFU/SEDI, Saclay and CNRS/LAL/SERDI, Orsay. It benefits from both the quick response of a time to digital converter (TDC) and the versatility of a waveform digitizer to perform accurate timing measurements. Thanks to the sampled signals, smart algorithms making best use of the pulse shape can be used to maximize time resolution. A software framework has been developed to analyse the SAMPIC output data and extract timing information by using either a constant fraction discriminator or a fast cross-correlation algorithm. SAMPIC timing capabilities together with the software framework have been tested using Gaussian signals generated by a signal generator or by silicon detectors pulsed with an infra-red laser. Under these ideal experimental conditions, the SAMPIC chip has proven to be capable of timing resolutions down to 4 (40) ps with synthesized (silicon detector) signals.

  6. Taxi Time Prediction at Charlotte Airport Using Fast-Time Simulation and Machine Learning Techniques

    Lee, Hanbong

    2016-01-01

    Accurate taxi time prediction is required for enabling efficient runway scheduling that can increase runway throughput and reduce taxi times and fuel consumptions on the airport surface. Currently NASA and American Airlines are jointly developing a decision-support tool called Spot and Runway Departure Advisor (SARDA) that assists airport ramp controllers to make gate pushback decisions and improve the overall efficiency of airport surface traffic. In this presentation, we propose to use Linear Optimized Sequencing (LINOS), a discrete-event fast-time simulation tool, to predict taxi times and provide the estimates to the runway scheduler in real-time airport operations. To assess its prediction accuracy, we also introduce a data-driven analytical method using machine learning techniques. These two taxi time prediction methods are evaluated with actual taxi time data obtained from the SARDA human-in-the-loop (HITL) simulation for Charlotte Douglas International Airport (CLT) using various performance measurement metrics. Based on the taxi time prediction results, we also discuss how the prediction accuracy can be affected by the operational complexity at this airport and how we can improve the fast time simulation model before implementing it with an airport scheduling algorithm in a real-time environment.

  7. Seismic response analysis of the PEC fast reactor building

    In order to compute the motion induced by the design earthquakes at the vessel supporting structure, a seismic response analysis was performed for the PEC fast reactor, taking into account the effects of soil-structure interaction by use of experimentally determined soil parameters. The main aim of he analysis was to evaluate the safety margins present in the design calculations. A detailed 3D finite element model was set up for fixed base analysis; from the results of the 3D model a simplified equivalent model of the structure was then derived for soil-structure interaction analysis. The mathematical model was validated and calibrated by using the results of the experimental dynamic tests performed on the reactor building. The results have shown the adequacy of the computation methodologies, and in particular of those on the use of the equivalent model. (author)

  8. Supersensitive, Fast-Response Nanowire Sensors by Using Schottky Contacts

    Hu, Youfan

    2010-05-31

    A Schottky barrier can be formed at the interface between a metal electrode and a semiconductor. The current passing through the metal-semiconductor contact is mainly controlled by the barrier height and barrier width. In conventional nanodevices, Schottky contacts are usually avoided in order to enhance the contribution made by the nanowires or nanotubes to the detected signal. We present a key idea of using the Schottky contact to achieve supersensitive and fast response nanowire-based nanosensors. We have illustrated this idea on several platforms: UV sensors, biosensors, and gas sensors. The gigantic enhancement in sensitivity of up to 5 orders of magnitude shows that an effective usage of the Schottky contact can be very beneficial to the sensitivity of nanosensors. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Surface Ice Module for Wind Turbine Dynamic Response Simulation Using FAST

    Yu, Bingbin; Karr, Dale G.; Song, Huimin; Sirnivas, Senu

    2016-06-03

    forces resulting from ice impact on the turbine support structure. The conditions considered in this module are specifically addressed in the ISO standard 19906:2010 for arctic offshore structures design consideration. Special consideration of lock-in vibrations is required due to the detrimental effects of such response with regard to fatigue and foundation/soil response. The use of FAST for transient, time domain simulation with the new ice module is well suited for such analyses.

  10. Fast Intrinsic Mode Decomposition of Time Series Data

    Lu, Louis Yu

    2008-01-01

    A fast convergent iterative method is introduced in this paper to find the intrinsic mode function (IMF) components of time series data, which is faster and more predictable than the Empirical Mode Decomposition method devised by the author of Hilbert Huang Transform. The method iteratively adjust the control points on the data function corresponding to the extrema of the refining IMF, the control points of the residue function are calculated as the median of the straight line segments passing through the data control points, the residue function is then constructed as the cubic spline function of the median points. The initial residue function is simply constructed as the straight line segments passing through the extrema of the differential of the data function. The refining IMF is the difference between the data function and the improved residue function. The IMF found can also reveal the riding waves on the steep edge of the data. The program to demonstrate the method is distributed under BSD license.

  11. Lifetime measurements in transitional nuclei by fast electronic scintillation timing

    Caprio, M. A.; Zamfir, N. V.; Casten, R. F.; Amro, H.; Barton, C. J.; Beausang, C. W.; Cooper, J. R.; Gürdal, G.; Hecht, A. A.; Hutter, C.; Krücken, R.; McCutchan, E. A.; Meyer, D. A.; Novak, J. R.; Pietralla, N.; Ressler, J. J.; Berant, Z.; Brenner, D. S.; Gill, R. L.; Regan, P. H.

    2002-10-01

    A new generation of experiments studying nuclei in spherical-deformed transition regions has been motivated by the introduction of innovative theoretical approaches to the treatment of these nuclei. The important structural signatures in the transition regions, beyond the basic yrast level properties, involve γ-ray transitions between low-spin, non-yrast levels, and so information on γ-ray branching ratios and absolute matrix elements (or level lifetimes) for these transitions is crucial. A fast electronic scintillation timing (FEST) system [H. Mach, R. L. Gill, and M. Moszyński, Nucl. Instrum. Methods A 280, 49 (1989)], making use of BaF2 and plastic scintillation detectors, has been implemented at the Yale Moving Tape Collector for the measurement of lifetimes of states populated in β^ decay. Experiments in the A100 (Pd, Ru) and A150 (Dy, Yb) regions have been carried out, and a few examples will be presented. Supported by the US DOE under grants and contracts DE-FG02-91ER-40609, DE-FG02-88ER-40417, and DE-AC02-98CH10886 and by the German DFG under grant Pi 393/1.

  12. 28 CFR 542.18 - Response time.

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Response time. 542.18 Section 542.18... REMEDY Administrative Remedy Program § 542.18 Response time. If accepted, a Request or Appeal is... later than the third calendar day after filing. If the time period for response to a Request or...

  13. Fast-Response Oxygen-Monitoring and Control System

    Singh, J. J.; Davis, W. T.; Puster, R. L.

    1986-01-01

    Oxygen sensor is Y2O3-stabilized ZrO2 ceramic disk maintained at 843 degrees C. Overall system response time reduced to about 0.2 second, equal to or less than 1 percent of tunnel run time. When test gas oxygen concentration differs from normal air concentration by 25 percent or more, alarm sounds, and emergency tunnel shutdown signal operates. New ZrO2 sensors intended for hypersonic-vehicle testing.

  14. A measurement of the response to fast neutrons of several materials dosemeters

    The response to fast neutrons was measured for three types of materials testing dosemeters: fast neutron dosimetry silicon diodes; beryllia, alumina and calcium fluoride TLDs; graphite walled ionisation chambers. The calibrations were made using a 3MW positive ion accelerator. The arrangement of the target, beam monitor and devices is described, and the measured fast neutron sensitivities are presented. (UK)

  15. Fasting, Circadian Rhythms, and Time-Restricted Feeding in Healthy Lifespan.

    Longo, Valter D; Panda, Satchidananda

    2016-06-14

    Most animals alternate periods of feeding with periods of fasting often coinciding with sleep. Upon >24 hr of fasting, humans, rodents, and other mammals enter alternative metabolic phases, which rely less on glucose and more on ketone body-like carbon sources. Both intermittent and periodic fasting result in benefits ranging from the prevention to the enhanced treatment of diseases. Similarly, time-restricted feeding (TRF), in which food consumption is restricted to certain hours of the day, allows the daily fasting period to last >12 hr, thus imparting pleiotropic benefits. Understanding the mechanistic link between nutrients and the fasting benefits is leading to the identification of fasting-mimicking diets (FMDs) that achieve changes similar to those caused by fasting. Given the pleiotropic and sustained benefits of TRF and FMDs, both basic science and translational research are warranted to develop fasting-associated interventions into feasible, effective, and inexpensive treatments with the potential to improve healthspan. PMID:27304506

  16. A LaBr3: Ce fast-timing array for DESPEC at FAIR

    The design of a fast-timing γ-ray detection array aimed at measuring sub-nanosecond half-lives using LaBr3:Ce scintillation crystals is presented. This array will complement novel and existing charged particle and neutron detector arrays at the low-energy branch of a fragment separator (Super-FRS) to be built within the NuSTAR collaboration as part of the future Facility for Anti-proton and Ion Research (FAIR). The array will be used in conjunction with the Advanced Implantation Detector Array (AIDA), to measure implant-decay correlations. Monte-Carlo simulations have been performed to determine the design of the proposed fast-timing array around a localised implantation point. In particular, simulations were used to determine the full-energy peak efficiencies for single cylindrical, conical and ‘hybrid’ detector geometries, as well as complete array configurations of ‘hybrid’ and ∅1.5 in.×2 in. cylindrical crystals. Timing precision calculations were then used to determine the timing response for each configuration based on its simulated efficiency. An informed decision based on the simulated efficiencies and timing precision calculations allowed the optimum configuration for the array to be determined

  17. Preoperative fasting times in elective surgical patients at a referral Hospital in Botswana

    Abebe, Worknehe Agegnehu; Rukewe, Ambrose; Bekele, Negussie Alula; Stoffel, Moeng; Dichabeng, Mompelegi Nicoh; Shifa, Jemal Zeberga

    2016-01-01

    Introduction Adults and children are required to fast before anaesthesia to reduce the risk of regurgitation and aspiration of gastric contents. However, prolonged periods of fasting are unnecessary and may cause complications. This study was conducted to evaluate preoperative fasting period in our centre and compare it with the ASA recommendations and factors that influence fasting periods. Methods This is a cross-sectional study of preoperative fasting times among elective surgical patients. A total numbers of 260 patients were interviewed as they arrived at the reception area of operating theatre using questionnaire. Results Majority of patients (98.1%) were instructed to fast from midnight. Fifteen patients (5.8%) reported that they were told the importance of preoperative fasting. The mean fasting period were 15.9±2.5 h (range 12.0-25.3 h) for solids and 15.3±2.3 h (range 12.0-22.0 h) for liquids. The mean duration of fasting was significantly longer for patients operated after midday compared to those operated before midday, p<0.001. Conclusion The mean fasting periods were 7.65 times longer for clear liquid and 2.5 times for solids than the ASA guidelines. It is imperative that the Hospital should establish Preoperative fasting policies and teach the staff who should ensure compliance with guidelines.

  18. Fast binarized time-reversed adapted-perturbation (b-TRAP) optical focusing inside scattering media

    Ma, Cheng; Liu, Yan; Wang, Lihong V

    2015-01-01

    Light scattering inhibits high-resolution optical imaging, manipulation and therapy deep inside biological tissue by preventing focusing. To form deep foci, wavefront-shaping and time-reversal techniques that break the optical diffusion limit have been developed. For in vivo applications, such focusing must provide high gain, high speed, and a large number of spatial modes. However, none of the previous techniques meet these requirements simultaneously. Here, we overcome this challenge by rapidly measuring the perturbed optical field within a single camera exposure followed by adaptively time-reversing the phase-binarized perturbation. Consequently, a phase-conjugated wavefront is synthesized within a millisecond, two orders of magnitude shorter than the digitally achieved record. We demonstrated real-time focusing in dynamic scattering media, and extended laser speckle contrast imaging to new depths. The unprecedented combination of fast response, high gain, and large mode count makes this work a major strid...

  19. A modified fast analog technique for determining luminescence decay times of scintillators

    The authors have modified their previous fast analog technique to determine the luminescence decay times of scintillators following an excitation with a Sr90 β-source. In the original technique, the sample was excited with a nitrogen-pumped dye laser, and the fluorescence pulses (consisting of typically 50 to 1,000 photons) were detected by a multichannel plate photomultiplier tube (MCP-PMT). The output from the MCP-PMT was directed to a fast waveform digitizer triggered externally by the exciting laser. In the modified technique, the digitizer acquires the fluorescence decay in the internal trigger mode, as no corresponding external trigger pulse is available from the Sr90 source. For efficient light collection from scintillators, an ellipsoidal mirror assembly has been tested. The fluorescence decays are acquired as multi-photon pulses and are subsequently corrected for the temporal instrument response by using a deconvolution technique. The overall time resolution of the technique is about 100 ps. The fluorescence decay time obtained using this technique for a commercial scintillator (SCSN-81) agrees well with literature. The authors also discuss the results on new epoxy-polymer based scintillators prepared in their laboratory. The primary motivation for this work was development of new scintillators with shorter fluorescence decay times for high collision rate experiments

  20. A Fast-Response Atmospheric Turbulence (FRAT) Probe with Gas-Sampling Ducts Project

    National Aeronautics and Space Administration — Aeroprobe proposes to design, construct and test an air-data probe with substantially higher frequency response than currently available. This fast-response...

  1. A Fast-Response Atmospheric Turbulence (FRAT) Probe with Gas-Sampling Ducts Project

    National Aeronautics and Space Administration — The objective of this proposal is to design, construct and test a high-frequency-response air-data probe, the Fast Response Atmospheric Turbulence probe (FRAT...

  2. FAST

    Zuidmeer-Jongejan, Laurian; Fernandez-Rivas, Montserrat; Poulsen, Lars K.;

    2012-01-01

    ABSTRACT: The FAST project (Food Allergy Specific Immunotherapy) aims at the development of safe and effective treatment of food allergies, targeting prevalent, persistent and severe allergy to fish and peach. Classical allergen-specific immunotherapy (SIT), using subcutaneous injections with...... aqueous food extracts may be effective but has proven to be accompanied by too many anaphylactic side-effects. FAST aims to develop a safe alternative by replacing food extracts with hypoallergenic recombinant major allergens as the active ingredients of SIT. Both severe fish and peach allergy are caused...... lower their threshold for fish or peach intake, thereby decreasing their anxiety and dependence on rescue medication....

  3. The Generalized Centroid Difference method for lifetime measurements via γ-γ coincidences using large fast-timing arrays

    Régis J.-M.

    2015-01-01

    Full Text Available A novel method for direct electronic “fast-timing” lifetime measurements of nuclear excited states via γ-γ coincidences using an array equipped with N very fast high-resolution LaBr3(Ce scintillator detectors is presented. The generalized centroid difference method provides two independent “start” and “stop” time spectra obtained without any correction by a superposition of the N(N – 1/2 calibrated γ-γ time difference spectra of the N detector fast-timing system. The two fast-timing array time spectra correspond to a forward and reverse gating of a specific γ-γ cascade and the centroid difference as the time shift between the centroids of the two time spectra provides a picosecond-sensitive mirror-symmetric observable of the set-up. The energydependent mean prompt response difference between the start and stop events is calibrated and used as a single correction for lifetime determination. These combined fast-timing array mean γ-γ zero-time responses can be determined for 40 keV < Eγ < 1.4 MeV with a precision better than 10 ps using a 152Eu γ-ray source. The new method is described with examples of (n,γ and (n,f,γ experiments performed at the intense cold-neutron beam facility PF1B of the Institut Laue-Langevin in Grenoble, France, using 16 LaBr3(Ce detectors within the EXILL&FATIMA campaign in 2013. The results are discussed with respect to possible systematic errors induced by background contributions.

  4. Properties of a fast timing detector using an electron multiplier

    A new timing detector for the time-of-flight method has been invented and successfully tested with heavy-ion beams. The detector consists of a thin foil and an electron multiplier. The best time resolution of 260 ps is obtained for 81Br. The time resolution is also studied in relation to the number of secondary electrons emitted from the foil. (orig.)

  5. Picosecond time measurement using ultra fast analog memories

    Breton, D.; Delagnes, E.; Maalmi, J.

    2009-01-01

    International audience The currently existing electronics dedicated to precise time measurement is mainly based on the use of constant fraction discriminators (CFD) associated with Time to Digital Converters (TDC). The constant fraction technique minimizes the time walk effect (dependency of timing on the pulse amplitude). Several attempts have been made to integrate CFD in multi-channel ASICs. But the time resolution measured on the most advanced one is of the order of 30 ps rms. Two main...

  6. Fast to forgive, slow to retaliate: intuitive responses in the ultimatum game depend on the degree of unfairness.

    Eamonn Ferguson

    Full Text Available Evolutionary accounts have difficulty explaining why people cooperate with anonymous strangers they will never meet. Recently models, focusing on emotional processing, have been proposed as a potential explanation, with attention focusing on a dual systems approach based on system 1 (fast, intuitive, automatic, effortless, and emotional and system 2 (slow, reflective, effortful, proactive and unemotional. Evidence shows that when cooperation is salient, people are fast (system 1 to cooperate, but with longer delays (system 2 they show greed. This is interpreted within the framework of the social heuristic hypothesis (SHH, whereby people overgeneralize potentially advantageous intuitively learnt and internalization social norms to 'atypical' situations. We extend this to explore intuitive reactions to unfairness by integrating the SHH with the 'fast to forgive, slow to anger' (FFSA heuristic. This suggests that it is advantageous to be prosocial when facing uncertainty. We propose that whether or not someone intuitively shows prosociality (cooperation or retaliation is moderated by the degree (certainty of unfairness. People should intuitively cooperate when facing mild levels of unfairness (fast to forgive but when given longer to decide about another's mild level of unfairness should retaliate (slow to anger. However, when facing severe levels of unfairness, the intuitive response is always retaliation. We test this using a series of one-shot ultimatum games and manipulate level of offer unfairness (50:50 60:40, 70:30, 80:20, 90:10 and enforced time delays prior to responding (1s, 2s, 8s, 15s. We also measure decision times to make responses after the time delays. The results show that when facing mildly unfair offers (60:40 people are fast (intuitive to cooperate but with longer delays reject these mildly unfair offers: 'fast to forgive, and slow to retaliate'. However, for severely unfair offers (90:10 the intuitive and fast response is to

  7. Contrasting Responses to Harvesting and Environmental Drivers of Fast and Slow Life History Species

    Antoni Quetglas; Lucía Rueda; Diego Alvarez-Berastegui; Beatriz Guijarro; Enric Massutí

    2016-01-01

    According to their main life history traits, organisms can be arranged in a continuum from fast (species with small body size, short lifespan and high fecundity) to slow (species with opposite characteristics). Life history determines the responses of organisms to natural and anthropogenic factors, as slow species are expected to be more sensitive than fast species to perturbations. Owing to their contrasting traits, cephalopods and elasmobranchs are typical examples of fast and slow strategi...

  8. Geosynchronous magnetic field responses to fast solar wind dynamic pressure enhancements: MHD field model

    T. R. Sun

    2012-08-01

    Full Text Available We performed global MHD simulations of the geosynchronous magnetic field in response to fast solar wind dynamic pressure (Pd enhancements. Taking three Pd enhancement events in 2000 as examples, we found that the main features of the total field B and the dominant component Bz can be efficiently predicted by the MHD model. The predicted B and Bz varies with local time, with the highest level near noon and a slightly lower level around mid-night. However, it is more challenging to accurately predict the responses of the smaller component at the geosynchronous orbit (i.e., Bx and By. In contrast, the limitations of T01 model in predicting responses to fast Pd enhancements are presented.

  9. The Fast Tracker Real Time Processor: high quality real-time tracking at ATLAS

    Stabile, A; The ATLAS collaboration

    2011-01-01

    As the LHC luminosity is ramped up to the design level of 1x1034 cm−2 s−1 and beyond, the high rates, multiplicities, and energies of particles seen by the detectors will pose a unique challenge. Only a tiny fraction of the produced collisions can be stored on tape and immense real-time data reduction is needed. An effective trigger system must maintain high trigger efficiencies for the most important physics and at the same time suppress the enormous QCD backgrounds. This requires massive computing power to minimize the online execution time of complex algorithms. A multi-level trigger is an effective solution for an otherwise impossible problem. The Fast Tracker (FTK)[1], [2] is a proposed upgrade to the current ATLAS trigger system that will operate at full Level-1 output rates and provide high quality tracks reconstructed over the entire detector by the start of processing in Level-2. FTK is a dedicated Super Computer based on a mixture of advanced technologies. The architecture broadly employs powerf...

  10. A Fasting-Responsive Signaling Pathway that Extends Life Span in C. elegans

    Masaharu Uno

    2013-01-01

    Full Text Available Intermittent fasting is one of the most effective dietary restriction regimens that extend life span in C. elegans and mammals. Fasting-stimulus responses are key to the longevity response; however, the mechanisms that sense and transduce the fasting stimulus remain largely unknown. Through a comprehensive transcriptome analysis in C. elegans, we find that along with the FOXO transcription factor DAF-16, AP-1 (JUN-1/FOS-1 plays a central role in fasting-induced transcriptional changes. KGB-1, one of the C. elegans JNKs, acts as an activator of AP-1 and is activated in response to fasting. KGB-1 and AP-1 are involved in intermittent fasting-induced longevity. Fasting-induced upregulation of the components of the SCF E3 ubiquitin ligase complex via AP-1 and DAF-16 enhances protein ubiquitination and reduces protein carbonylation. Our results thus identify a fasting-responsive KGB-1/AP-1 signaling pathway, which, together with DAF-16, causes transcriptional changes that mediate longevity, partly through regulating proteostasis.

  11. A Capacitor-Free, Fast Transient Response Linear Voltage Regulator In a 180nm CMOS

    Deleuran, Alexander N.; Lindbjerg, Nicklas; Pedersen, Martin K.;

    2015-01-01

    A 1.8 V capacitor-free linear regulator with fast transient response based on a new topology with a fast and slow regulation loop is presented. The design has been laid out and simulated in a 0.18 µm CMOS process. The design has a low component count and is tailored for system-on-chip integration...

  12. Achieving fast timing performance with multiplexed SiPMs

    Bieniosek, M. F.; Cates, J. W.; Levin, C. S.

    2016-04-01

    Using time of flight (ToF) measurements for positron emission tomography (PET) is an attractive avenue for increasing the signal to noise (SNR) ratio of PET images. However, achieving excellent time resolution required for high SNR gain using silicon photomultipliers (SiPM) requires many resource heavy high bandwidth readout channels. A method of multiplexing many SiPM signals into a single electronic channel would greatly simplify ToF PET systems. However, multiplexing SiPMs degrades time resolution because of added dark counts and signal shaping. In this work the relative contribution of dark counts and signal shaping to timing degradation is simulated and a baseline correction technique to mitigate the effect of multiplexing on the time resolution of analog SiPMs is simulated and experimentally verified. A charge sharing network for multiplexing is proposed and tested. Results show a full width at half maximum (FWHM) coincidence time resolution of 232+/- 2 ps for a single 3 mm  ×  3 mm  ×  20 mm LYSO scintillation crystals coupled to an array of sixteen 3 mm  ×  3 mm SiPMs that are multiplexed to a single timing channel (in addition to 4 position channels). A 4× 4 array of 3 mm  ×  3 mm  ×  20 mm LFS crystals showed an average FWHM coincidence time resolution of 278+/- 7 ps using the same timing scheme. All experiments were performed at room temperature with no thermal regulation. These results show that excellent time resolution for ToF can be achieved with a highly multiplexed analog SiPM readout.

  13. Dynamics of the flood response to slow-fast landscape-climate feedbacks

    Perdigão, R. A. P.; Blöschl, G.

    2015-06-01

    The dynamical evolution of the flood response to landscape-climate feedbacks is evaluated in a joint nonlinear statistical-dynamical approach. For that purpose, a spatiotemporal sensitivity analysis is conducted on hydrological data from 1976-2008 over 804 catchments throughout Austria, and a general, data-independent nonlinear dynamical model is built linking floods with climate (via precipitation), landscape (via elevation) and their feedbacks. These involve nonlinear scale interactions, with landform evolution processes taking place at the millennial scale (slow dynamics), and climate adjusting in years to decades (fast dynamics). The results show that floods are more responsive to spatial (regional) than to temporal (decadal) variability. Catchments from dry lowlands and high wetlands exhibit similarity between the spatial and temporal sensitivities (spatiotemporal symmetry) and low landscape-climate codependence, suggesting they are not coevolving significantly. However, intermediate regions show differences between those sensitivities (symmetry breaks) and higher landscape-climate codependence, suggesting undergoing coevolution. The break of symmetry is an emergent behaviour from nonlinear feedbacks within the system. A new coevolution index is introduced relating spatiotemporal symmetry with relative characteristic celerities, which need to be taken into account in hydrological space-time trading. Coevolution is expressed here by the interplay between slow and fast dynamics, represented respectively by spatial and temporal characteristics. The dynamical model captures emerging features of the flood dynamics and nonlinear landscape-climate feedbacks, supporting the nonlinear statistical assessment of spatiotemporally asymmetric flood change. Moreover, it enables the dynamical estimation of flood changes in space and time from the given knowledge at different spatiotemporal conditions. This study ultimately brings to light emerging signatures of change in

  14. Validation of the AECL response time tester

    The response time of a nuclear safety (trip) channel is an important safety parameter, and an ISA standard requires nuclear operators to measure the response times of their trip instrumentation. As a major aid to facilitate this measurement, AECL (Chalk River) has designed and built a Response Time Tester (RTT) for pressure and differential-pressure transmitters. The RTT is mostly automated for ease of use, is self-checking, and complies with the requirements of ISA Standard, S67.06. The RTT was first checked for repeatability and self-consistency. Secondly, it was successfully validated against an independent measurement, namely the transfer function as measured using the natural in-service noise. This validation was done using two Bailey transmitters, which had the unfortunate property of having their response times as functions of the testing conditions. In all instances, after correcting for this Bailey nonlinearity, the RTT performance met its accuracy specification of ±(5% + 5 ms). (author)

  15. OFDM receiver for fast time-varying channels using block-sparse Bayesian learning

    Barbu, Oana-Elena; Manchón, Carles Navarro; Rom, Christian;

    2016-01-01

    characterized with a basis expansion model using a small number of terms. As a result, the channel estimation problem is posed as that of estimating a vector of complex coefficients that exhibits a block-sparse structure, which we solve with tools from block-sparse Bayesian learning. Using variational Bayesian...... inference, we embed the channel estimator in a receiver structure that performs iterative channel and noise precision estimation, intercarrier interference cancellation, detection and decoding. Simulation results illustrate the superior performance of the proposed receiver over state-of-art receivers.......We propose an iterative algorithm for OFDM receivers operating over fast time-varying channels. The design relies on the assumptions that the channel response can be characterized by a few non-negligible separable multipath components, and the temporal variation of each component gain can be well...

  16. Fast Calculation of Response of Scatterers in Uniaxial Laminates

    Zhong, Yu; Chen, Xudong; Ding, Ping-Ping; Lambert, Marc; Lesselier, Dominique

    2014-01-01

    The volume integral equation method, usually implemented via the method of moments (MoM), is a popular approach to many scattering problems, like when inhomogeneous bodies are embedded within planarly layered media and made to interact with given sources, as henceforth considered. When the layered media are isotropic, the construction of the impedance matrix of the MoM, the bottleneck of the method, can be fast since one is able to accelerate the calculation of the 1-D Sommerfeld integrals [1...

  17. Fast Human Brain Magnetic Resonance Responses Associated With Epileptiform Spikes

    Sundaram, Padmavathi; Wells, William M.; Mulkern, Robert V.; Bubrick, Ellen J.; Bromfield, Edward B.; Münch, Mirjam; Orbach, Darren B.

    2010-01-01

    Neuronal currents produce local electromagnetic fields that can potentially modulate the phase of the magnetic resonance signal and thus provide a contrast mechanism tightly linked to neuronal activity. Previous work has demonstrated the feasibility of direct MRI of neuronal activity in phantoms and cell culture, but in vivo efforts have yielded inconclusive, conflicting results. The likelihood of detecting and validating such signals can be increased with (i) fast gradient-echo echo-planar i...

  18. Fast and Flexible Multivariate Time Series Subsequence Search

    National Aeronautics and Space Administration — Multivariate Time-Series (MTS) are ubiquitous, and are generated in areas as disparate as sensor recordings in aerospace systems, music and video streams, medical...

  19. Time to let go of CARP? Not so fast

    Toby C. Monsod; Sharon A. Piza

    2014-01-01

    The following note seeks to clarify the appreciation of data pertaining to agrarian reform as used in the discussion paper "CARP: time to let go" (henceforth Fabella (2014)). Fabella (2014) has three parts: the first part argues that "the cumulative weight of evidence suggests that the hypothesis that in economic terms CARP is a government failure has not been rejected." The second part offers possible reasons for that failure. The third part concludes, saying it is time to let go.

  20. Fast response of electron-scale turbulence to auxiliary heating cessation in National Spherical Torus Experiment

    Ren, Y.; Wang, W. X.; LeBlanc, B. P.; Guttenfelder, W.; Kaye, S. M.; Ethier, S.; Mazzucato, E.; Bell, R. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Lee, K. C. [National Fusion Research Institute, Daejeon 305-806 (Korea, Republic of); Domier, C. W. [University of California at Davis, Davis, California 95616 (United States); Smith, D. R. [University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Yuh, H. [Nova Photonics, Inc., Princeton, New Jersey 08540 (United States)

    2015-11-15

    In this letter, we report the first observation of the fast response of electron-scale turbulence to auxiliary heating cessation in National Spherical Torus eXperiment [Ono et al., Nucl. Fusion 40, 557 (2000)]. The observation was made in a set of RF-heated L-mode plasmas with toroidal magnetic field of 0.55 T and plasma current of 300 kA. It is observed that electron-scale turbulence spectral power (measured with a high-k collective microwave scattering system) decreases significantly following fast cessation of RF heating that occurs in less than 200 μs. The large drop in the turbulence spectral power has a short time delay of about 1–2 ms relative to the RF cessation and happens on a time scale of 0.5–1 ms, much smaller than the energy confinement time of about 10 ms. Power balance analysis shows a factor of about 2 decrease in electron thermal diffusivity after the sudden drop of turbulence spectral power. Measured small changes in equilibrium profiles across the RF cessation are unlikely able to explain this sudden reduction in the measured turbulence and decrease in electron thermal transport, supported by local linear stability analysis and both local and global nonlinear gyrokinetic simulations. The observations imply that nonlocal flux-driven mechanism may be important for the observed turbulence and electron thermal transport.

  1. Fast response of electron-scale turbulence to auxiliary heating cessation in National Spherical Torus Experiment

    In this letter, we report the first observation of the fast response of electron-scale turbulence to auxiliary heating cessation in National Spherical Torus eXperiment [Ono et al., Nucl. Fusion 40, 557 (2000)]. The observation was made in a set of RF-heated L-mode plasmas with toroidal magnetic field of 0.55 T and plasma current of 300 kA. It is observed that electron-scale turbulence spectral power (measured with a high-k collective microwave scattering system) decreases significantly following fast cessation of RF heating that occurs in less than 200 μs. The large drop in the turbulence spectral power has a short time delay of about 1–2 ms relative to the RF cessation and happens on a time scale of 0.5–1 ms, much smaller than the energy confinement time of about 10 ms. Power balance analysis shows a factor of about 2 decrease in electron thermal diffusivity after the sudden drop of turbulence spectral power. Measured small changes in equilibrium profiles across the RF cessation are unlikely able to explain this sudden reduction in the measured turbulence and decrease in electron thermal transport, supported by local linear stability analysis and both local and global nonlinear gyrokinetic simulations. The observations imply that nonlocal flux-driven mechanism may be important for the observed turbulence and electron thermal transport

  2. Development of a new time-amplitude converter with tunnel diodes for improving fast neutron spectrometry by time of flight

    New time-amplitude converter with Esaki diodes, the events being preselected before analysis, allows for realizing a fast neutron spectrometer by time-of-flight with an 1.5 * 10-9 s overall time resolution for 12C (n,n') at 14 MeV. (author)

  3. Fast γ-ray coincidence timing using a BGO detector array in a nuclear reaction experiment

    The (7Li, 7Be) nuclear charge-exchange reaction has been investigated at E(7Li)=350 MeV. Coincidences were measured between the charged 7Be reaction products in the focal plane of a magnetic spectrometer and 430-keV Doppler-shifted γ-rays from the decay in flight of excited 7Be ejectiles. The latter were detected in a compact BGO detector array. Fast timing was used to optimize the separation between prompt and randoms events. The BGO output signals display the statistical distribution of the arrival times of individual photoelectrons from the photocathode in the photomultiplier tubes. A timing resolution of 6.5 ns relative to the accelerator RF was obtained. A simple model was successfully developed to simulate the BGO output signals with a statistical distribution of a predetermined number of photoelectrons modulated by the light output response of the scintillator and the single-photoelectron gain distribution and transit time through the photomultiplier tube. It is concluded that the timing resolution is primarily limited by the small number of photoelectrons. ((orig.))

  4. Fast and Furious: Rapid Response to Young Supernovae

    Cao, Yi; Kulkarni, Shrinivas R.; Nugent, Peter E.; Kasliwal, Mansi M.

    2016-01-01

    Observations of supernovae within a few days of their explosion provide entirely diagnostics to probe the nature of supernova progenitors. Since 2013, I have used the intermediate Palomar Transient Factory (iPTF) to systematically study extraordinarily young supernovae. In this talk, I will give an overview of iPTF survey design, summarize the design and implementation of the near real-time discovery pipeline and then describe the rapid-response follow-up. The highlights from my thesis are: 1) We observed a strong declining UV emission from a low-velocity Type Ia supernova which is consistent with the expected emission from a supernova slamming into a companion star. Evidently some Type Ia supernovae arise from the so-called "single degenerate" channel. 2) We identified the first progenitor candidate of a Type Ib supernova in the pre-explosion HST images. Our multi-wavelength observations of this young Type Ib supernova constrain its progenitor to be smaller than several solar radii and with strong mass loss, consistent with our current ideas that the progenitor should be a Wolf-Rayet star. I will end my talk with prospects for this field with the upcoming Zwicky Transient Facility.

  5. FAST TRACK COMMUNICATION: Dynamical 'breaking' of time reversal symmetry

    Gutkin, Boris

    2007-08-01

    It is a common assumption that quantum systems with time reversal invariance and classically chaotic dynamics have energy spectra distributed according to GOE type of statistics. Here we present a class of systems which fail to follow this rule. We show that for convex billiards of constant width with time reversal symmetry and 'almost' chaotic dynamics the energy-level distribution is of GUE type. The effect is due to the lack of ergodicity in the 'momentum' part of the phase space and, as we argue, is generic in two dimensions.

  6. The Role of Time in Fast-Food Purchasing Behavior in the United States

    Hamrick, Karen; Okrent, Abigail

    2014-01-01

    Meals, snacks, and beverages purchased at fast-food restaurants account for an increasingly large share of a typical American’s food budget and have been blamed for Americans’ expanding waistlines and poor diet quality. This study uses data from the 2003-11 American Time Use Survey to examine the effects of time-use behaviors, prices, sociodemographic characteristics, labor force participation, and prices on fast-food purchasing patterns in the United States before and after the Great Recessi...

  7. Time-resolved fast-neutron imaging with a pulse-counting image intensifier

    Dangendorf, Volker; Lauck, Ronald; Kaufmann, Frank; Barnstedt, Juergen; Breskin, Amos; Jagutzki, Ottmar; Kraemer, Michael; Vartsky, David

    2006-01-01

    A new imaging method that combines high-efficiency fast-neutron detection with sub-ns time resolution is presented. This is achieved by exploiting the high neutron detection efficiency of a thick scintillator and the fast timing capability and flexibility of light-pulse detection with a dedicated image intensifier. The neutron converter is a plastic scintillator slab or, alternatively, a scintillating fibre screen. The scintillator is optically coupled to a pulse counting image intensifier wh...

  8. Fast natural color mapping for night-time imagery

    Hogervorst, M.A.; Toet, A.

    2010-01-01

    We present a new method to render multi-band night-time imagery (images from sensors whose sensitive range does not necessarily coincide with the visual part of the electromagnetic spectrum, e.g. image intensifiers, thermal camera's) in natural daytime colors. The color mapping is derived from the c

  9. Real time control of a fast RF impedance matching system

    A real time control system has been developed to maintain an RF impedance match in the ion cyclotron range of frequencies (ICRF). This system is designed to adjust output parameters with a cycle period of approximately 100 μseconds using commercially available VME based components and a UNIX workstation host. Advanced Ferrite Technologies (AFT) has developed the hybrid tuning system (HTS) which has the capability of tracking a mismatch on the time scale of milliseconds (2.5 MW, 60 MHz) by varying the magnetic field bias of ferrite loaded transmission lines. The control algorithm uses a combination of neural network and fuzzy logic techniques. Initial results of a test facility using a low power prototype are presented. 2 refs., 5 figs

  10. Fast algorithm for real-time rings reconstruction

    Ammendola, R.; Bauce, M.; Gianoli, A.; Graverini, E.(Physik-Institut, Universität Zürich, Zürich, Switzerland); Lamanna, G.; Lonardo, A.; Messina, A.; Neri, I.; M. Palombo; Pantaleo, F; Paolucci, P. S.; Piandani, R.; Biagioni, A.; Pontisso, L.; M. Rescigno

    2015-01-01

    This Conference focuses on the application of GPUs in High Energy Physics (HEP), expanding on the trend of previous workshops on the topic and pointing to establishing a recurrent series. All different applications of massively parallel computing in HEP will be addressed, from computational speed-ups in online and offline data selection and analysis to hard real-time applications in low-level triggering, to Monte Carlo simulations for lattice QCD. Both current activities and plans on foreseen...

  11. A time series evaluation of the FAST National Stroke Awareness Campaign in England.

    Darren Flynn

    Full Text Available OBJECTIVE: In February 2009, the Department of Health in England launched the Face, Arm, Speech, and Time (FAST mass media campaign, to raise public awareness of stroke symptoms and the need for an emergency response. We aimed to evaluate the impact of three consecutive phases of FAST using population-level measures of behaviour in England. METHODS: Interrupted time series (May 2007 to February 2011 assessed the impact of the campaign on: access to a national stroke charity's information resources (Stroke Association [SA]; emergency hospital admissions with a primary diagnosis of stroke (Hospital Episode Statistics for England; and thrombolysis activity from centres in England contributing data to the Safe Implementation of Thrombolysis in Stroke UK database. RESULTS: Before the campaign, emergency admissions (and patients admitted via accident and emergency [A&E] and thrombolysis activity was increasing significantly over time, whereas emergency admissions via general practitioners (GPs were decreasing significantly. SA webpage views, calls to their helpline and information materials dispatched increased significantly after phase one. Website hits/views, and information materials dispatched decreased after phase one; these outcomes increased significantly during phases two and three. After phase one there were significant increases in overall emergency admissions (505, 95% CI = 75 to 935 and patients admitted via A&E (451, 95% CI = 26 to 875. Significantly fewer monthly emergency admissions via GPs were reported after phase three (-19, 95% CI =  -29 to -9. Thrombolysis activity per month significantly increased after phases one (3, 95% CI = 1 to 6, and three (3, 95% CI = 1 to 4. CONCLUSIONS: Phase one had a statistically significant impact on information seeking behaviour and emergency admissions, with additional impact that may be attributable to subsequent phases on information seeking behaviour, emergency admissions via GPs, and

  12. Waveform Timing Performance of a 5 GS/s Fast Pulse Sampling Module with DRS4

    Wang, Jinhong; An, Qi

    2015-01-01

    We first clarify timing issues of non-uniform sampling intervals regarding a 5 GS/s fast pulse sampling module with DRS4. Calibration strategy is proposed, and as a result, the waveform timing performance is improved to be below 10 ps RMS. We then further evaluate waveform timing performance of the module by comparing with a 10 GS/s oscilloscope in a setup with plastic scintillators and fast PMTs. Different waveform timing algorithms are employed for analysis, and the module shows comparable timing performance with that of the oscilloscope.

  13. Time-of-flight measurement of fast neutrons with Timepix detectors

    Bergmann, B.; Nelson, R. O.; O'Donnell, J. M.; Pospisil, S.; Solc, J.; Takai, H.; Vykydal, Z.

    2014-05-01

    Timepix pixel detectors have been used to study the response of silicon hybrid pixel detectors to fast neutrons from a pulsed neutron beam at WNR FP30R, a 14 m long flight path, in the Los Alamos Neutron Science Center. Neutrons with kinetic energies up to 600 MeV were available. In order to enhance the conversion of neutrons to energetic charged particles, several converter foils and filters were attached to the 300 μm thick silicon sensor, i.e. polyethylene, polyethylene with aluminum, 6LiF, 6LiF with aluminum, aluminum. The Time-of-Arrival mode of the Timepix detectors has permitted the application of the Time-of-Flight (TOF) technique for the assignment of the detected interactions in the form of clusters (groups of adjacent pixels) in the pixel matrix, to the kinetic energies of the incident neutrons. It was found that, for lower neutron energies ( ~ MeV range) the cluster rates below the polyethylene and the polyethylene and aluminum region, produced by recoil protons, are a good measure for the mean kinetic energies of neutrons. For energies above 50 MeV nuclear reactions in the silicon dominate the detector response. In this energy range the shape of the clusters indicates the neutron kinetic energy.

  14. Parallel Configuration For Fast Superconducting Strip Line Detectors With Very Large Area In Time Of Flight Mass Spectrometry

    We realized a very fast and large Superconducting Strip Line Detector based on a parallel configuration of nanowires. The detector with size 200x200 μm2 recorded a sub-nanosecond pulse width of 700 ps in FWHM (400 ps rise time and 530 ps relaxation time) for lysozyme monomers/multimers molecules accelerated at 175 keV in a Time of Flight Mass Spectrometer. This record is the best in the class of superconducting detectors and comparable with the fastest NbN superconducting single photon detector of 10x10 μm2. We succeeded in acquiring mass spectra as the first step for a scale-up to ∼mm pixel size for high throughput MS analysis, while keeping a fast response.

  15. Ultra Fast Timing Measurements at $^{78}$Ni and $^{132}$Sn

    2002-01-01

    We propose to measure level lifetimes in the exotic nuclei of $^{81}$Ga and $^{80}$Ga in the vicinity of $^{78}$Ni and of $^{135}$Sb and $^{134}$Sb above $^{132}$Sn by the time-delayed technique. These are relatively simple nuclear systems with a few particles and/or holes outside of the doubly-magic core thus can be treated rather precisely within the shell model. The anticipated new structure information on these nuclei, and in particular the lifetime results will put constraints on the model parameters and will serve to verify their predictions. The selected nuclei are some of the most exotic ones just above $^{78}$Ni or $^{132}$Sn, where the transition rates can be studied at present. Of the strongest interest is the nucleus of $^{81}$Ga, which has only 3 valence protons outside of $^{78}$Ni with the lowest proton orbits being $p_{3/2}$ and $f_{5/2}$. The Ml transition between these states, although allowed by the selection rules, should be $\\textit{l}$-forbidden thus very slow. This should give rise to a...

  16. Y2K issues for real time computer systems for fast breeder test reactor

    Presentation shows the classification of real time systems related to operation, control and monitoring of the fast breeder test reactor. Software life cycle includes software requirement specification, software design description, coding, commissioning, operation and management. A software scheme in supervisory computer of fast breeder test rector is described with the twenty years of experience in design, development, installation, commissioning, operation and maintenance of computer based supervision control system for nuclear installation with a particular emphasis on solving the Y2K problem

  17. Signal and Noise Analysis in TRION -Time-Resolved Integrative Optical Fast Neutron Detector

    Vartsky, D.; Feldman, G.; Mor, I.; Goldberg, M B; Bar, D.; Dangendorf, V.

    2008-01-01

    TRION is a sub-mm spatial resolution fast neutron imaging detector, which employs an integrative optical time-of-flight technique. The detector was developed for fast neutron resonance radiography, a method capable of detecting a broad range of conventional and improvised explosives. In this study we have analyzed in detail, using Monte-Carlo calculations and experimentally determined parameters, all the processes that influence the signal and noise in the TRION detector. In contrast to event...

  18. Ultra-high throughput real-time instruments for capturing fast signals and rare events

    Buckley, Brandon Walter

    Wide-band signals play important roles in the most exciting areas of science, engineering, and medicine. To keep up with the demands of exploding internet traffic, modern data centers and communication networks are employing increasingly faster data rates. Wide-band techniques such as pulsed radar jamming and spread spectrum frequency hopping are used on the battlefield to wrestle control of the electromagnetic spectrum. Neurons communicate with each other using transient action potentials that last for only milliseconds at a time. And in the search for rare cells, biologists flow large populations of cells single file down microfluidic channels, interrogating them one-by-one, tens of thousands of times per second. Studying and enabling such high-speed phenomena pose enormous technical challenges. For one, parasitic capacitance inherent in analog electrical components limits their response time. Additionally, converting these fast analog signals to the digital domain requires enormous sampling speeds, which can lead to significant jitter and distortion. State-of-the-art imaging technologies, essential for studying biological dynamics and cells in flow, are limited in speed and sensitivity by finite charge transfer and read rates, and by the small numbers of photo-electrons accumulated in short integration times. And finally, ultra-high throughput real-time digital processing is required at the backend to analyze the streaming data. In this thesis, I discuss my work in developing real-time instruments, employing ultrafast optical techniques, which overcome some of these obstacles. In particular, I use broadband dispersive optics to slow down fast signals to speeds accessible to high-bit depth digitizers and signal processors. I also apply telecommunication multiplexing techniques to boost the speeds of confocal fluorescence microscopy. The photonic time stretcher (TiSER) uses dispersive Fourier transformation to slow down analog signals before digitization and

  19. Electrochromic device of PEDOT-PANI hybrid system for fast response and high optical contrast

    Kang, Joo-Hee; Oh, Yeon-Ji; Hwang, Seong-Ju; Choy, Jin-Ho [Center for Intelligent Nano-Bio Materials (CINBM), Department of Chemistry and Nano Sciences, Ewha Womans University, Seoul 120-750 (Korea); Paek, Seung-Min [Center for Intelligent Nano-Bio Materials (CINBM), Department of Chemistry and Nano Sciences, Ewha Womans University, Seoul 120-750 (Korea); Beamline Research Division, Pohang Accelerator Laboratory, Pohang 790-784 (Korea)

    2009-12-15

    An organic-organic hybrid system composed of the polyaniline (PANI) and poly-(3,4-ethylenedioxythiophene) (PEDOT) with controlled thickness was developed successfully in order to realize synergetic effects in electrochromic (EC) properties such as optical contrast and color-switching rate. From the UV transmittance spectra, we found that the optical contrast ({delta}%T) was enhanced up to 6-72% at the wavelength of 580 nm compared with the previous PANI-PEDOT ECDs. Furthermore, the optimized ECD showed an extremely fast response time of less than 160 ms. It is therefore concluded that such a complementary full.cell system of PEDOT-PANI ECD is applicable as an optical device. (author)

  20. Simulation of response functions of fast neutron sensors and development of thin neutron silicon sensor.

    Takada, Masashi; Nakamura, Takashi; Matsuda, Mikihiko; Nunomiya, Tomoya

    2014-10-01

    On radiation detection using silicon sensor, signals are produced from collected charges in a depletion layer; however, for high-energy particles, this depletion layer is extended due to funnelling phenomenon. The lengths of charge collection were experimentally obtained from proton peak energies in measured pulse-heights. The length is extended with increasing proton energy of up to 6 MeV, and then, is constant over 6 MeV. The response functions of fast neutron sensors were simulated for 5- and 15-MeV monoenergetic and (252)Cf neutron sources using the Monte Carlo N-Particle eXtended code. The simulation results agree well with the experimental ones, including the effect of funnelling phenomenon. In addition, a thin silicon sensor was developed for a new real-time personal neutron dosemeter. Photon sensitivity is vanishingly smaller than neutron one by a factor of 5×10(-4). PMID:24516186

  1. Simulation of response functions of fast neutron sensors and development of thin neutron silicon sensor

    On radiation detection using silicon sensor, signals are produced from collected charges in a depletion layer; however, for high-energy particles, this depletion layer is extended due to funnelling phenomenon. The lengths of charge collection were experimentally obtained from proton peak energies in measured pulse-heights. The length is extended with increasing proton energy of up to 6 MeV, and then, is constant over 6 MeV. The response functions of fast neutron sensors were simulated for 5- and 15-MeV monoenergetic and 252Cf neutron sources using the Monte Carlo N-Particle eXtended code. The simulation results agree well with the experimental ones, including the effect of funnelling phenomenon. In addition, a thin silicon sensor was developed for a new real-time personal neutron dosemeter. Photon sensitivity is vanishingly smaller than neutron one by a factor of 5x10-4. The length of the depletion layer is extended due to the effect of funnelling phenomenon. With increasing proton energy, the length of charge collection is increased; and over 6 MeV of proton energy, the length stays constant. The response functions of fast neutron sensors were simulated for 5- and 15-MeV monoenergetic and 252Cf neutron sources. The simulated results agree well with the experimental ones, considering the effect of funnelling phenomenon. Using this simulation, the response functions of >20 MeV can be obtained. The simulation for high-energy neutrons helps one to develop new personal neutron dosemeters for radiation protection of aircrew. The thin silicon sensor operates as a totally depleted silicon detector, confirmed on a basis of the constant proton peak energy with bias voltage. The thin silicon sensor can be used for new personal neutron dosemeters with negligible photon sensitivity. It was vanishingly smaller than the neutron sensitivity by a factor of 5x10-4. (authors)

  2. Wave-induced Hydroelastic response of fast monohull ships

    Jensen, Jørgen Juncher

    1996-01-01

    of a quadratic strip theory formulated in the frequency domain. The springing response is thereby excited partly be resonance and partly by non-linear excitation. Special emphasis is given to the influence of springing on fatigue damage as the extreme responses even for very flexible ships are quite...... natural frequencies of the global hull modes can be relatively low compared to the frequency of wave encounter. In the present paper the effect of hull flexibility on the wave-induced springing vibrations is investigated in stationary stochastic seaways. The calculations are performed within the framework...

  3. Time Domain Response of the ARIANNA Detector

    Barwick, S W; Besson, D Z; Hanson, J C; Klein, S R; Kleinfelder, S A; Piasecki, M; Ratzlaff, K; Reed, C; Roumi, M; Stezelberger, T; Tatar, J; Walker, J; Young, R; Zou, L

    2014-01-01

    The Antarctic Ross Ice Shelf Antenna Neutrino Array (ARIANNA) is a high-energy neutrino detector designed to record the Askaryan electric field signature of cosmogenic neutrino interactions in ice. To understand the inherent radio-frequency (RF) neutrino signature, the time-domain response of the ARIANNA RF receiver must be measured. ARIANNA uses Create CLP5130-2N log-periodic dipole arrays (LPDAs). The associated effective height operator converts incident electric fields to voltage waveforms at the LDPA terminals. The effective height versus time and incident angle was measured, along with the associated response of the ARIANNA RF amplifier. The results are verified by correlating to field measurements in air and ice, using oscilloscopes. Finally, theoretical models for the Askaryan electric field are combined with the detector response to predict the neutrino signature.

  4. 29 CFR 1610.9 - Responses: timing.

    2010-07-01

    ... 29 Labor 4 2010-07-01 2010-07-01 false Responses: timing. 1610.9 Section 1610.9 Labor Regulations Relating to Labor (Continued) EQUAL EMPLOYMENT OPPORTUNITY COMMISSION AVAILABILITY OF RECORDS Production or... reasonably be expected to pose an imminent threat to the life or physical safety of an individual; or...

  5. RESPONSE TIMES IN DECISION-MAKING TASKS.

    DAGLE, EVERETT F.; AND OTHERS

    THE HUMAN OPERATOR AFFECTS TOTAL PERFORMANCE OF SEMI-AUTOMATED SYSTEMS, BUT LITTLE IS KNOWN ABOUT HIS SOURCES OF ERROR, PARTICULARLY WITH RESPECT TO RESPONSE TIME. UNDER CONTROLLED LABORATORY CONDITIONS, 37 FRESHMEN AND SOPHOMORE GIRLS ATTENDING JUNIOR COLLEGE WERE ASKED TO GUESS A SERIES OF RANDOM NUMBERS GENERATED BY AN ELECTROMECHANICAL SYSTEM…

  6. Ultra-fast timing detectors to probe exotic properties of nuclei using RIB facility

    Datta, Ushasi; Rahaman, A

    2016-01-01

    Recently, the facilities of radioactive ion beam (RIB) combined with advanced detector systems provide us unique opportunity to probe the exotic properties of the nuclei with unusual neutron-to-proton ratio. In this article, a study of characterization of different types of ultra-fast timing detectors: a special type of gas detector (multi-strip multi-gap resistive plate chamber, MMRPC) ($\\sigma$ $<$100 ps), scintillators array ( viz., $LaBr_3:Ce$) (timing resolution ($\\sigma<$250 ps) are being presented. A brief discussion on usage of these different types of ultra-fast timing detector systems at radioactive ion beam facilities is also included.

  7. Count-to-count time interval distribution analysis in a fast reactor

    The most important kinetic parameters have been measured at the zero power fast reactor CORAL-I by means of the reactor noise analysis in the time domain, using measurements of the count-to-count time intervals. (Author) 69 refs

  8. Fast Time and Space Parallel Algorithms for Solution of Parabolic Partial Differential Equations

    Fijany, Amir

    1993-01-01

    In this paper, fast time- and Space -Parallel agorithms for solution of linear parabolic PDEs are developed. It is shown that the seemingly strictly serial iterations of the time-stepping procedure for solution of the problem can be completed decoupled.

  9. High-Accuracy and Fast-Response Flywheel Torque Control

    2014-01-01

    Compared with current mode flywheel torque controller, speed mode torque controller has superior disturbance rejection capability. However, the speed loop delay reduces system dynamic response speed. To solve this problem, a two-degrees-of-freedom controller (2DOFC) which consists of a feedback controller (FBC) and a command feedforward controller (FFC) is proposed. The transfer function of FFC is found based on the inverse model of motor drive system, whose parameters are identified by recur...

  10. Evaluation of Fast-Time Wake Vortex Models using Wake Encounter Flight Test Data

    Ahmad, Nashat N.; VanValkenburg, Randal L.; Bowles, Roland L.; Limon Duparcmeur, Fanny M.; Gloudesman, Thijs; van Lochem, Sander; Ras, Eelco

    2014-01-01

    This paper describes a methodology for the integration and evaluation of fast-time wake models with flight data. The National Aeronautics and Space Administration conducted detailed flight tests in 1995 and 1997 under the Aircraft Vortex Spacing System Program to characterize wake vortex decay and wake encounter dynamics. In this study, data collected during Flight 705 were used to evaluate NASA's fast-time wake transport and decay models. Deterministic and Monte-Carlo simulations were conducted to define wake hazard bounds behind the wake generator. The methodology described in this paper can be used for further validation of fast-time wake models using en-route flight data, and for determining wake turbulence constraints in the design of air traffic management concepts.

  11. A signal distribution board for the timing and fast control master of the CBM experiment

    For the CBM experiment a Timing and Fast-Control (TFC) system is being developed. In the detector readout, FPGA-based data processing boards (DPB) are organized in a large number of computing crates. At the crate level, the TFC master is connected to one TFC slave per crate, whereas the DPB AMCs are interconnected by the crates' infrastructure. In this article, an FMC-based signal distribution board is proposed allowing the transmission of a high-quality clock and timing and fast-control data from and to connected TFC slaves at distances of about 30 meters using twisted-pair cables

  12. Development and validation of a two-dimensional fast-response flood estimation model

    Judi, David R [Los Alamos National Laboratory; Mcpherson, Timothy N [Los Alamos National Laboratory; Burian, Steven J [UNIV OF UTAK

    2009-01-01

    A finite difference formulation of the shallow water equations using an upwind differencing method was developed maintaining computational efficiency and accuracy such that it can be used as a fast-response flood estimation tool. The model was validated using both laboratory controlled experiments and an actual dam breach. Through the laboratory experiments, the model was shown to give good estimations of depth and velocity when compared to the measured data, as well as when compared to a more complex two-dimensional model. Additionally, the model was compared to high water mark data obtained from the failure of the Taum Sauk dam. The simulated inundation extent agreed well with the observed extent, with the most notable differences resulting from the inability to model sediment transport. The results of these validation studies complex two-dimensional model. Additionally, the model was compared to high water mark data obtained from the failure of the Taum Sauk dam. The simulated inundation extent agreed well with the observed extent, with the most notable differences resulting from the inability to model sediment transport. The results of these validation studies show that a relatively numerical scheme used to solve the complete shallow water equations can be used to accurately estimate flood inundation. Future work will focus on further reducing the computation time needed to provide flood inundation estimates for fast-response analyses. This will be accomplished through the efficient use of multi-core, multi-processor computers coupled with an efficient domain-tracking algorithm, as well as an understanding of the impacts of grid resolution on model results.

  13. Time Domain Response of the ARIANNA Detector

    Barwick, S. W.; Berg, E. C.; Besson, D. Z.; Hanson, J. C.; Klein, S. R.; Kleinfelder, S. A.; Piasecki, M.; Ratzlaff, K.; Reed, C.; Roumi, M.; Stezelberger, T.; Tatar, J.; Walker, J; Young, R.; Zou, L.

    2014-01-01

    The Antarctic Ross Ice Shelf Antenna Neutrino Array (ARIANNA) is a high-energy neutrino detector designed to record the Askaryan electric field signature of cosmogenic neutrino interactions in ice. To understand the inherent radio-frequency (RF) neutrino signature, the time-domain response of the ARIANNA RF receiver must be measured. ARIANNA uses Create CLP5130-2N log-periodic dipole arrays (LPDAs). The associated effective height operator converts incident electric fields to voltage waveform...

  14. Effect of short-term fasting on lipolytic responsiveness in normal and obese human subjects

    In this study the rate of lipolysis (fatty acid and glycerol release into blood) has been quantified in both normal weight and obese volunteers after both 15 and 87 h of fasting. In each study, the basal rate and subsequent response to epinephrine infusion were determined. The rate of appearance (R/sub a/) of free fatty acids (FFA) and glycerol were quantified by infusion of [1-13C]palmitate and D-5-glycerol, respectively. Substrate flux rates per unit of body fat mass and lean body mass were calculated from total body water measurements using H218O dilution. In normal volunteers, the basal R/sub a/ FFA and R/sub a/ glycerol rose markedly with 87 h of fasting, whereas the increases were more modest in the obese subjects. However, the rate of mobilization of fat, in relation to the lean body mass, was higher in the obese subjects than in the normal subjects after 15 h of fasting, and the values were similar in both groups after 87 h of fasting. There was an increased lipolytic response to epinephrine after fasting in both groups. This increased sensitivity may have resulted from the enhancement of fatty acid-triglyceride substrate cycling that occurred after fasting

  15. Effect of short-term fasting on lipolytic responsiveness in normal and obese human subjects

    Wolfe, R.R.; Peters, E.J.; Klein, S.; Holland, O.B.; Rosenblatt, J.; Gary, H. Jr.

    1987-02-01

    In this study the rate of lipolysis (fatty acid and glycerol release into blood) has been quantified in both normal weight and obese volunteers after both 15 and 87 h of fasting. In each study, the basal rate and subsequent response to epinephrine infusion were determined. The rate of appearance (R/sub a/) of free fatty acids (FFA) and glycerol were quantified by infusion of (1- TC)palmitate and D-5-glycerol, respectively. Substrate flux rates per unit of body fat mass and lean body mass were calculated from total body water measurements using H2 YO dilution. In normal volunteers, the basal R/sub a/ FFA and R/sub a/ glycerol rose markedly with 87 h of fasting, whereas the increases were more modest in the obese subjects. However, the rate of mobilization of fat, in relation to the lean body mass, was higher in the obese subjects than in the normal subjects after 15 h of fasting, and the values were similar in both groups after 87 h of fasting. There was an increased lipolytic response to epinephrine after fasting in both groups. This increased sensitivity may have resulted from the enhancement of fatty acid-triglyceride substrate cycling that occurred after fasting.

  16. Fast and Slow Precipitation Responses to Individual Climate Forcers: A PDRMIP Multimodel Study

    Samset, B. H.; Myhre, G.; Forster, P.M.; Hodnebrog, O.; Andrews, T.; Faluvegi, G.; Flaschner, D.; Kasoar, M.; Kharin, V.; Kirkevag, A.; Shindell, D.; Voulgarakis, A.

    2016-01-01

    Precipitation is expected to respond differently to various drivers of anthropogenic climate change. We present the first results from the Precipitation Driver and Response Model Intercomparison Project (PDRMIP), where nine global climate models have perturbed CO2, CH4, black carbon, sulfate, and solar insolation. We divide the resulting changes to global mean and regional precipitation into fast responses that scale with changes in atmospheric absorption and slow responses scaling with surface temperature change. While the overall features are broadly similar between models, we find significant regional intermodel variability, especially over land. Black carbon stands out as a component that may cause significant model diversity in predicted precipitation change. Processes linked to atmospheric absorption are less consistently modeled than those linked to top-of-atmosphere radiative forcing. We identify a number of land regions where the model ensemble consistently predicts that fast precipitation responses to climate perturbations dominate over the slow, temperature-driven responses.

  17. TRANC – a novel fast-response converter to measure total reactive atmospheric nitrogen

    V. Wolff

    2012-05-01

    Full Text Available The input and loss of plant available nitrogen (reactive nitrogen: Nr from/to the atmosphere can be an important factor for the productivity of ecosystems and thus for its carbon and greenhouse gas exchange. We present a novel converter for reactive nitrogen (TRANC: Total Reactive Atmospheric Nitrogen Converter, which offers the opportunity to quantify the sum of all airborne reactive nitrogen compounds (∑Nr in high time resolution. The basic concept of the TRANC is the full conversion of all Nr to nitrogen monoxide (NO within two reaction steps. Initially, reduced Nr compounds are being oxidised, and oxidised Nr compounds are thermally converted to lower oxidation states. Particulate Nr is being sublimated and oxidised or reduced afterwards. In a second step, remaining higher nitrogen oxides or those generated in the first step are catalytically converted to NO with carbon monoxide used as reduction gas. The converter is combined with a fast response chemiluminescence detector (CLD for NO analysis and its performance was tested for the most relevant gaseous and particulate Nr species under both laboratory and field conditions. Recovery rates during laboratory tests for NH3 and NO2 were found to be 95 and 99%, respectively, and 97% when the two gases were combined. In-field longterm stability over an 11-month period was approved by a value of 91% for NO2. Effective conversion was also found for ammonium and nitrate containing particles. The recovery rate of total ambient Nr was tested against the sum of individual measurements of NH3, HNO3, HONO, NH4+, NO3−, and NOx using a combination of different well-established devices. The results show that the TRANC-CLD system precisely captures fluctuations in ∑Nr concentrations and also matches the sum of all individual Nr compounds measured by the different single techniques. The TRANC features a specific design with very short distance between the sample air inlet and the place where the thermal

  18. Rapid qualitative urinary tract infection pathogen identification by SeptiFast real-time PCR.

    Lutz E Lehmann

    Full Text Available BACKGROUND: Urinary tract infections (UTI are frequent in outpatients. Fast pathogen identification is mandatory for shortening the time of discomfort and preventing serious complications. Urine culture needs up to 48 hours until pathogen identification. Consequently, the initial antibiotic regimen is empirical. AIM: To evaluate the feasibility of qualitative urine pathogen identification by a commercially available real-time PCR blood pathogen test (SeptiFast® and to compare the results with dipslide and microbiological culture. DESIGN OF STUDY: Pilot study with prospectively collected urine samples. SETTING: University hospital. METHODS: 82 prospectively collected urine samples from 81 patients with suspected UTI were included. Dipslide urine culture was followed by microbiological pathogen identification in dipslide positive samples. In parallel, qualitative DNA based pathogen identification (SeptiFast® was performed in all samples. RESULTS: 61 samples were SeptiFast® positive, whereas 67 samples were dipslide culture positive. The inter-methodological concordance of positive and negative findings in the gram+, gram- and fungi sector was 371/410 (90%, 477/492 (97% and 238/246 (97%, respectively. Sensitivity and specificity of the SeptiFast® test for the detection of an infection was 0.82 and 0.60, respectively. SeptiFast® pathogen identifications were available at least 43 hours prior to culture results. CONCLUSION: The SeptiFast® platform identified bacterial DNA in urine specimens considerably faster compared to conventional culture. For UTI diagnosis sensitivity and specificity is limited by its present qualitative setup which does not allow pathogen quantification. Future quantitative assays may hold promise for PCR based UTI pathogen identification as a supplementation of conventional culture methods.

  19. Metabolic responses to fasting and refeeding in lean and genetically obese rats.

    Rothwell, N J; Saville, M E; Stock, M J

    1983-05-01

    Injection of norepinephrine (NE) (25 micrograms/100 g body wt) caused a similar rise in metabolic rate in lean and obese (fa/fa) Zucker rats, but 3-day fasting suppressed the response in lean rats and enhanced the rise in obese mutants. Triiodothyronine (T3) injection (10 micrograms/100 g body wt) caused a significantly greater rise in oxygen consumption (Vo2) in obese than lean rats, but the response was attenuated by fasting in all animals. The thermic response to a single meal of either mixed composition, carbohydrate, or protein (40 kJ) was much smaller in obese rats than lean, but the response to the mixed nutrient meal was similar for all rats after a 3-day fast. Refeeding 3-day fasted lean rats with a single carbohydrate meal (40 kJ) caused a rise in plasma T3 levels after 3 h and a delayed increase in metabolic rate 24 h later. Injection of NE instead of refeeding caused a similar delayed rise in metabolic rate. Carbohydrate refeeding had no effect on plasma T3 levels or oxygen consumption in 3-day fasted obese Zuckers, but injection of NE did produce a significant increase in metabolic rate after 24 h. Refeeding 3-day fasted rats with protein (40 kJ) caused a rise in oxygen consumption 24 h later in lean animals but had no effect in obese animals. The data from lean Zucker rats confirm previous findings in Sprague-Dawley rats and suggest that the thermic response to refeeding involves a complex interaction between the sympathetic nervous system and thyroid hormones. Obese Zuckers responded normally to NE and T3, indicating that their reduced thermogenesis after food may be due to insensitivity to nutrient availability or an inability to activate the sympathetic nervous system. PMID:6846570

  20. Formulation and optimization of fast dissolving intraoral drug delivery system for clobazam using response surface methodology.

    Bala, Rajni; Khanna, Sushil; Pawar, Pravin K

    2013-07-01

    Clobazam is a newer 1,5-benzodiazepine used for the treatment of epilepsy. It is better tolerated and less sedating than other benzodiazepines. Absorption of the drug can be impacted by oral fast dissolving dosage form; this may have implications for epilepsy in pediatrics and those having difficulty in swallowing tablets/capsules resulting in improved patient compliance. The purpose of the present investigation was to formulate and optimize clobazam oro-dissolving tablets by direct compression method using response surface methodology (RSM). Oro-dispersible tablets of clobazam were prepared by direct compression method using crospovidone (2-6%) as a superdisintegrant, microcrystalline cellulose (MCC) (20-40%) was used as diluents along with directly compressible mannitol to enhance mouth feel. A 3(2) full factorial design was applied to investigate the combined effect of two formulation variables: amount of crospovidone and MCC over the independent variables disintegration time, wetting time and percent drug release. Disintegration time showed by all formulations was found to be in the range of 24.3-193 s based on evaluation parameters the formulation containing 6% of crospovidone and 30% of MCC showed promising performance against all other formulations. The results demonstrated that the RSM could efficiently be applied for the formulation of clobazam oro-dispersible tablets; therefore, constitute an advance in the management of epileptic attacks. PMID:24083203

  1. Formulation and optimization of fast dissolving intraoral drug delivery system for clobazam using response surface methodology

    Rajni Bala

    2013-01-01

    Full Text Available Clobazam is a newer 1,5-benzodiazepine used for the treatment of epilepsy. It is better tolerated and less sedating than other benzodiazepines. Absorption of the drug can be impacted by oral fast dissolving dosage form; this may have implications for epilepsy in pediatrics and those having difficulty in swallowing tablets/capsules resulting in improved patient compliance. The purpose of the present investigation was to formulate and optimize clobazam oro-dissolving tablets by direct compression method using response surface methodology (RSM. Oro-dispersible tablets of clobazam were prepared by direct compression method using crospovidone (2-6% as a superdisintegrant, microcrystalline cellulose (MCC (20-40% was used as diluents along with directly compressible mannitol to enhance mouth feel. A 3 2 full factorial design was applied to investigate the combined effect of two formulation variables: amount of crospovidone and MCC over the independent variables disintegration time, wetting time and percent drug release. Disintegration time showed by all formulations was found to be in the range of 24.3-193 s based on evaluation parameters the formulation containing 6% of crospovidone and 30% of MCC showed promising performance against all other formulations. The results demonstrated that the RSM could efficiently be applied for the formulation of clobazam oro-dispersible tablets; therefore, constitute an advance in the management of epileptic attacks.

  2. Ultra fast proton response of myoglobin upon ligand dissociation

    In numerous biological processes, the ensuing protein structural changes accompanying a reaction at a specific site must spatially extend to mesoscopic dimensions to achieve a biological function. The molecular mechanism of cooperativity in oxygen binding of hemoglobin (Hb) is one of the classical problems in this aspect. The binding of small molecular ligands to the hemes in Hb is a highly localized perturbation. Nonetheless, this localized perturbation initiates a sequence of propagating structural events that culminates in a change of quaternary structure. The large-amplitude motions at the quaternary level, which form a communication link at the subunit interface, are driven by changes of the tertiary structure upon ligation. In this respect, myoglobin (Mb), which is structurally very similar to a subunit of Hb serves as a model system for the tertiary relaxation processes. Figure 1 demonstrates time-resolved UVRR difference spectra expanded the region of 650-1850 cm-1. The top and bottom traces correspond to the contracted probe-only spectrum and equilibrium deoxyMb minus MbCO difference spectrum, respectively. Tryptophan (Trp) and tyrosine (Tyr) bands appeared in the UVRR spectra are labeled by W and Y. In delay times between 5 and 300 ps, negative difference bands of W18, W16, and W3 modes showed little intensity change, on the other hand, negative difference band at 1620 cm-1 appreciably decreased in intensity. The intensity of W1 band with 226-nm excitation is less than one third of that of W3 band and the intensity of Trp bands other than W1 is invariant; hence, the intensity change of difference signal at 1620 cm-1 observed at 5 to 300 ps can be attributed to the intensity restoration of Y8a band. At 2.5 ns time delay, the transient difference spectrum does not coincide with the equilibrium difference spectrum. This means that the structural rearrangements toward the deoxy structure are not completed at 2.5 ns. Horse Mb has two Tyr residues: Tyr103 and

  3. Waveform timing performance of a 5 GS/s fast pulse sampling module with DRS4

    Wang, Jin-Hong; Liu, Shu-Bin; An, Qi

    2015-10-01

    We first clarify timing issues of non-uniform sampling intervals regarding a 5 GS/s fast pulse sampling module with DRS4. A calibration strategy is proposed, and as a result, the waveform timing performance is improved to below 10 ps RMS. We then further evaluate waveform-timing performance of the module by comparing with a 10 GS/s oscilloscope in a setup with plastic scintillators and fast PMTs. Different waveform timing algorithms are employed for analysis, and the module shows comparable timing performance with that of the oscilloscope. Supported by Knowledge Innovation Program of the Chinese Academy of Sciences (KJCX2-YW-N27), and National Natural Science Foundation of China (11175176)

  4. Fast and true-to-life application of daytime colours to night-time imagery

    Hogervorst, M.A.; Toet, A.

    2007-01-01

    We developed a fast and efficient method to derive and apply a natural colour mapping for night-time imagery from multi-band sensors. The colour mapping is derived from the combination of a multi-band image and a corresponding natural colour reference image. The mapping optimizes the match between t

  5. Measurement of fast assembly spectra using time-of-flight method

    Measurement of neutron spectra made in fast subcritical assemblies HUG 3 and PHUG 3 (uranium-graphite and plutonium-graphite) utilizing time-of-flight techniques are described. The matrix were excited by the pulsed neutron source from the BCMN Linac beam impinging on a target of natural uranium. Details of the experimental procedure, safety studies, detector calibration and data reduction are given

  6. A UV LED-based fast-pulsed photoelectron source for time-of-flight studies

    Valerius, K.; Beck, M.; Arlinghaus, H.; Bonn, J.; Hannen, V.M.; Hein, H.; Ostrick, B.; Streubel, S.; Weinheimer, C.; Zbořil, Miroslav

    2009-01-01

    Roč. 11, - (2009), 063018/1-063018/16. ISSN 1367-2630 R&D Projects: GA MŠk LA318 Institutional research plan: CEZ:AV0Z10480505 Keywords : fast-pulsed * high-resolution * time-of-flight Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.312, year: 2009

  7. Fast MCMC sampling for Markov jump processes and continuous time Bayesian networks

    Rao, Vinayak

    2012-01-01

    Markov jump processes and continuous time Bayesian networks are important classes of continuous time dynamical systems. In this paper, we tackle the problem of inferring unobserved paths in these models by introducing a fast auxiliary variable Gibbs sampler. Our approach is based on the idea of uniformization, and sets up a Markov chain over paths by sampling a finite set of virtual jump times and then running a standard hidden Markov model forward filtering-backward sampling algorithm over states at the set of extant and virtual jump times. We demonstrate significant computational benefits over a state-of-the-art Gibbs sampler on a number of continuous time Bayesian networks.

  8. Fast bolometric response by high T sub c detectors measured with subnanosecond synchrotron radiation

    Carr, G.L.; Quijada, M.; Tanner, D.B. (Department of Physics, University of Florida, Gainesville, Florida 32611 (USA)); Hirschmugl, C.J.; Williams, G.P. (National Synchrotron Light Source, Brookhaven National Laboratory, Upton, NY 11973 (USA)); Etemad, S.; Dutta, B.; DeRosa, F.; Inam, A.; Venkatesan, T. (Bell Communications Research, Red Bank, New Jersey 07701 (USA)); Xi, X. (Department of Physics, Rutgers University, Piscataway, New Jersey 08855 (USA))

    1990-12-17

    We have measured a fast response by thin-film YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} detectors to pulsed, broadband, infrared radiation. Synchrotron light from an electron storage ring was used as the infrared source, providing subnanosecond pulses from far infrared through visible. Pulse responsivities as high as 10{sup 6} V/J and as fast as 4 ns have been observed. For film thicknesses in the range 400--3200 A, the detector response follows the film absorptivity while the speed varies inversely with thickness, suggesting a bolometric mechanism. Calculations based on such a model are in accord with the data. We find no evidence for any nonbolometric components in the response.

  9. The passive response of the Integral Fast Reactor concept to the chilled inlet accident

    Simple methods are described for bounding the passive response of a metal fueled liquid-metal cooled reactor to the chilled inlet accident. Calculation of these bounds for a prototype of the Integral Fast Reactor concept shows that failure limits --- eutectic melting, sodium boiling and fuel pin failure --- are not exceeded. 2 refs., 1 fig., 2 tabs

  10. A novel fast gas chromatography method for higher time resolution measurements of speciated monoterpenes in air

    Jones, C. E.; Kato, S.; Nakashima, Y.; Kajii, Y.

    2014-05-01

    Biogenic emissions supply the largest fraction of non-methane volatile organic compounds (VOC) from the biosphere to the atmospheric boundary layer, and typically comprise a complex mixture of reactive terpenes. Due to this chemical complexity, achieving comprehensive measurements of biogenic VOC (BVOC) in air within a satisfactory time resolution is analytically challenging. To address this, we have developed a novel, fully automated Fast Gas Chromatography (Fast-GC) based technique to provide higher time resolution monitoring of monoterpenes (and selected other C9-C15 terpenes) during plant emission studies and in ambient air. To our knowledge, this is the first study to apply a Fast-GC based separation technique to achieve quantification of terpenes in ambient air. Three chromatography methods have been developed for atmospheric terpene analysis under different sampling scenarios. Each method facilitates chromatographic separation of selected BVOC within a significantly reduced analysis time compared to conventional GC methods, whilst maintaining the ability to quantify individual monoterpene structural isomers. Using this approach, the C9-C15 BVOC composition of single plant emissions may be characterised within a 14.5 min analysis time. Moreover, in-situ quantification of 12 monoterpenes in unpolluted ambient air may be achieved within an 11.7 min chromatographic separation time (increasing to 19.7 min when simultaneous quantification of multiple oxygenated C9-C10 terpenoids is required, and/or when concentrations of anthropogenic VOC are significant). These analysis times potentially allow for a twofold to fivefold increase in measurement frequency compared to conventional GC methods. Here we outline the technical details and analytical capability of this chromatographic approach, and present the first in-situ Fast-GC observations of 6 monoterpenes and the oxygenated BVOC (OBVOC) linalool in ambient air. During this field deployment within a suburban forest

  11. Ionization chamber with fast timing properties and good energy resolution for fission fragment detection

    A twin ionization chamber for fission fragment detection is described. The chamber allows to extract both, fast timing- and energy proportional signals. A time resolution of 1.62 ns FWHM was obtained between two fission fragments detected in the two halves of the chamber. For 241Am α-particles the chamber gave an energy resolution of 1.3 percent. As counting gas methane NTP was used

  12. A fast rise time high voltage pulse generator for bounded-wave EMP simulator

    A high voltage pulse generator with fast rise time is developed. The output wave of this generator is presented. The electromagnetic environment with 1.2 ns or 2.8 ns rise time and 50 ns pulse width can be produced when this generator is connected to bounded-wave EMP simulator which is used to investigate the EMP coupling effects of electrical equipment. (authors)

  13. Aroclor 1254 exposure reduces disease resistance and innate immune responses in fasted arctic charr

    Maule, A.G.; Jorgensen, E.H.; Vijayan, M.M.; Killie, J.-E.A.

    2005-01-01

    To examine the immunological impacts of polychlorinated biphenyls (PCBs) in an environmentally relevant way, we orally contaminated Arctic charr (Salvelinus alpinus) with Aroclor 1254. After contamination, fish were either fed (0 and 100 mg Aroclor 1254 kg-1 fish wt) or fasted (0, 1, 10, and 100 mg kg-1) to mimic cycles of feeding-fasting experienced by Arctic animals. After four months, PCB concentrations in muscle were the same in fasted and fed fish; however, PCBs in kidneys of fed fish were 33 to 50% of those in fasted fish. Arctic charr were exposed to Aeromonas salmonicida, the bacteria responsible for furunculosis, by cohabitation with infected conspecifics. Fasted fish had a significant trend toward lower survival with higher dose of PCBs - from 68% in controls to 48% in treatment involving 100 mg kg-1. Independent of PCB contamination, fed fish had the lowest survival; we attribute this to stress associated with establishing and maintaining feeding hierarchies. A significant decrease in the activity of lysozyme was observed in skin mucus, as was hemagglutination ability of a putative rhamnose lectin in fasted, but not in fed, PCB-treated fish. These results demonstrate the immunosuppressive effects of PCBs on Arctic charr, and they illustrate the importance of considering environmentally relevant nutritional status in ecotoxicological studies.

  14. Gaining control over responses to implicit attitude tests: Implementation intentions engender fast responses on attitude-incongruent trials.

    Webb, Thomas L; Sheeran, Paschal; Pepper, John

    2012-03-01

    The present research investigated whether forming implementation intentions could promote fast responses to attitude-incongruent associations (e.g., woman-manager) and thereby modify scores on popular implicit measures of attitude. Expt 1 used the Implicit Association Test (IAT) to measure associations between gender and science versus liberal arts. Planning to associate women with science engendered fast responses to this category-attribute pairing and rendered summary scores more neutral compared to standard IAT instructions. Expt 2 demonstrated that forming egalitarian goal intentions is not sufficient to produce these effects. Expt 3 extended these findings to a different measure of implicit attitude (the Go/No-Go Association Task) and a different stereotypical association (Muslims-terrorism). In Expt 4, managers who planned to associate women with superordinate positions showed more neutral IAT scores relative to non-planners and effects were maintained 3 weeks later. In sum, implementation intentions enable people to gain control over implicit attitude responses. PMID:22435844

  15. Time-dependent Networks as Models to Achieve Fast Exact Time-table Queries

    Brodal, Gerth Stølting; Jacob, Rico

    We consider efficient algorithms for exact time-table queries, i.e. algorithms that find optimal itineraries. We propose to use time-dependent networks as a model and show advantages of this approach over space-time networks as models.......We consider efficient algorithms for exact time-table queries, i.e. algorithms that find optimal itineraries. We propose to use time-dependent networks as a model and show advantages of this approach over space-time networks as models....

  16. Time-Dependent Networks as Models to Achieve Fast Exact Time-Table Queries

    Brodal, Gert Stølting; Jacob, Rico

    2003-01-01

    We consider efficient algorithms for exact time-table queries, i.e. algorithms that find optimal itineraries for travelers using a train system. We propose to use time-dependent networks as a model and show advantages of this approach over space-time networks as models.......We consider efficient algorithms for exact time-table queries, i.e. algorithms that find optimal itineraries for travelers using a train system. We propose to use time-dependent networks as a model and show advantages of this approach over space-time networks as models....

  17. A real-time dynamic holographic material using a fast photochromic molecule

    Ishii, Norihito; Kato, Tetsuya; Abe, Jiro

    2012-01-01

    We have developed a real-time, dynamic holographic material that exhibits rapid colouration upon irradiation with UV light and successive fast thermal bleaching within tens of milliseconds at room temperature. Photochromic polymer films were prepared by a simple solution-casting method from the benzene solution of the mixture of the photochromic molecule, poly(ethyl acrylate), and poly(phenoxyethyl acrylate). The real-time control of holographic images using the photochromic polymer film yields a speed equivalent to the time resolution of the human eye. This new type of dynamic holographic material based on fast photochromism opens up an exciting new area of research in the future development of a large dynamic 3D display. PMID:23139865

  18. Fast and Slow Responses of the South Asian Monsoon System to Anthropogenic Aerosols

    Ganguly, Dilip; Rasch, Philip J.; Wang, Hailong; Yoon, Jin-Ho

    2012-09-25

    Using a global climate model with fully predictive aerosol life cycle, we investigate the fast and slow responses of the South Asian monsoon system to anthropogenic aerosol forcing. Our results show that the feedbacks associated with sea surface temperature (SST) change caused by aerosols play a more important role than the aerosol's direct impact on radiation, clouds and land surface (rapid adjustments) in shaping the total equilibrium climate response of the monsoon system to aerosol forcing. Inhomogeneous SST cooling caused by anthropogenic aerosols eventually reduces the meridional tropospheric temperature gradient and the easterly shear of zonal winds over the region, slowing down the local Hadley cell circulation, decreasing the northward moisture transport, and causing a reduction in precipitation over South Asia. Although total responses in precipitation are closer to the slow responses in general, the fast component dominates over land areas north of 25°N. Our results also show an east-west asymmetry in the fast responses to anthropogenic aerosols causing increases in precipitation west of 80°E but decreases east of it.

  19. Effect of fasting on the transit time of 144Ce in the mouse gut

    Our work with G.I. absorption of actinide elements indicates greater absorption by fasted animals than by animals on regular diets (Weiss and Walburg, undated). Residence time of a metallic compound in the gut may be an important factor influencing G.I. absorption. Cerium-144 (III) chloride was administered by gavage to fasted mice and to mice on regular feed. The G.I. tract was excised, cut into sections, and the activity of each section determined as a function of time after dosing. Our results indicate rapid transit of 144CeCl3 along the empty mouse gut. One hour after dosing, about half the Ce is in the cecal contents; about 40% remains in stomach contents. Twelve hours after dosing, only about 2% remains in the cecum; by 16 hours, almost the entire dose has been cleared from the intestine. Transit times in mice with stomach and intestines containing food were 12 hours longer than in fasted mice. These results lead to the conclusion that factors other than G.I. residence time determine G.I. absorption of actinides in mice

  20. Joint Modeling of Ability and Differential Speed Using Responses and Response Times.

    Fox, Jean-Paul; Marianti, Sukaesi

    2016-01-01

    With computerized testing, it is possible to record both the responses of test takers to test questions (i.e., items) and the amount of time spent by a test taker in responding to each question. Various models have been proposed that take into account both test-taker ability and working speed, with the many models assuming a constant working speed throughout the test. The constant working speed assumption may be inappropriate for various reasons. For example, a test taker may need to adjust the pace due to time mismanagement, or a test taker who started out working too fast may reduce the working speed to improve accuracy. A model is proposed here that allows for variable working speed. An illustration of the model using the Amsterdam Chess Test data is provided. PMID:27269482

  1. Very fast doped LaBr.sub.3 scintillators and time-of-flight PET

    Shah, Kanai S.

    2006-10-31

    The present invention concerns very fast scintillator materials capable of resolving the position of an annihilation event within a portion of a human body cross-section. In one embodiment, the scintillator material comprises LaBr.sub.3 doped with cerium. Particular attention is drawn to LaBr.sub.3 doped with a quantity of Ce that is chosen for improving the timing properties, in particular the rise time and resultant timing resolution of the scintillator, and locational capabilities of the scintillator.

  2. Tunable graphene micro-emitters with fast temporal response and controllable electron emission

    Wu, Gongtao; Wei, Xianlong; Gao, Song; Chen, Qing; Peng, Lianmao

    2016-01-01

    Microfabricated electron emitters have been studied for half a century for their promising applications in vacuum electronics. However, tunable microfabricated electron emitters with fast temporal response and controllable electron emission still proves challenging. Here, we report the scaling down of thermionic emitters to the microscale using microfabrication technologies and a Joule-heated microscale graphene film as the filament. The emission current of the graphene micro-emitters exhibits a tunability of up to six orders by a modest gate voltage. A turn-on/off time of less than 1 μs is demonstrated for the graphene micro-emitters, indicating a switching speed about five orders of magnitude faster than their bulky counterparts. Importantly, emission performances of graphene micro-emitters are controllable and reproducible through engineering graphene dimensions by microfabrication technologies, which enables us to fabricate graphene micro-emitter arrays with uniform emission performances. Graphene micro-emitters offer an opportunity of realizing large-scale addressable micro-emitter arrays for vacuum electronics applications. PMID:27160693

  3. Tunable graphene micro-emitters with fast temporal response and controllable electron emission

    Wu, Gongtao; Wei, Xianlong; Gao, Song; Chen, Qing; Peng, Lianmao

    2016-05-01

    Microfabricated electron emitters have been studied for half a century for their promising applications in vacuum electronics. However, tunable microfabricated electron emitters with fast temporal response and controllable electron emission still proves challenging. Here, we report the scaling down of thermionic emitters to the microscale using microfabrication technologies and a Joule-heated microscale graphene film as the filament. The emission current of the graphene micro-emitters exhibits a tunability of up to six orders by a modest gate voltage. A turn-on/off time of less than 1 μs is demonstrated for the graphene micro-emitters, indicating a switching speed about five orders of magnitude faster than their bulky counterparts. Importantly, emission performances of graphene micro-emitters are controllable and reproducible through engineering graphene dimensions by microfabrication technologies, which enables us to fabricate graphene micro-emitter arrays with uniform emission performances. Graphene micro-emitters offer an opportunity of realizing large-scale addressable micro-emitter arrays for vacuum electronics applications.

  4. Fast response dry-type artificial molecular muscles with [c2]daisy chains

    Iwaso, Kazuhisa; Takashima, Yoshinori; Harada, Akira

    2016-06-01

    Hierarchically organized myosin and actin filaments found in biological systems exhibit contraction and expansion behaviours that produce work and force by consuming chemical energy. Inspired by these naturally occurring examples, we have developed photoresponsive wet- and dry-type molecular actuators built from rotaxane-based compounds known as [c2]daisy chains (specifically, [c2]AzoCD2 hydrogel and [c2]AzoCD2 xerogel). These actuators were prepared via polycondensation between four-armed poly(ethylene glycol) and a [c2]daisy chain based on α-cyclodextrin as the host component and azobenzene as a photoresponsive guest component. The light-induced actuation arises from the sliding motion of the [c2]daisy chain unit. Ultraviolet irradiation caused the gels to bend towards the light source. The response of the [c2]AzoCD2 xerogel, even under dry conditions, is very fast (7° every second), which is 10,800 times faster than the [c2]AzoCD2 hydrogel (7° every 3 h). In addition, the [c2]AzoCD2 xerogel was used as a crane arm to lift an object using ultraviolet irradiation to produce mechanical work.

  5. The potential influence of gastric acid secretion during fasting on digestion time in leopard sharks (Triakis semifasciata).

    Papastamatiou, Yannis P

    2007-05-01

    Vertebrates are known to differ in their response of gastric acid secretion during periods of fasting, yet the reasons for these differences remain unclear. Previously, continuous measurements of gastric pH in leopard sharks (Triakis semifasciata) had determined that acid secretion in this species is continuous. In order to determine if maintaining an empty acidic stomach may reduce digestion time of a subsequent meal, a simple descriptive model based on acid secretion rates was developed. In vivo gastric acid secretion rates were measured using an auto-titration technique. Acid secretion rates were pH dependent, with rates of 6.1+/-3.0 (+/-1 SD) mmol/h when gastric pH was >2.5, and 1.7+/-0.8 mmol/h when pH was 2.0-2.5. Analysis by Western blots suggests that pepsin secretion occurs within 1 h of feeding, and that there is a de-coupling of acid and pepsin secretion. The model estimates that digestion time can be reduced by 5.7+/-1.3 h and pepsin activity increased by 10-100% during that time if the stomach is acidic before feeding. Gastric acid secretion during fasting is hypothesized to reduce digestion time of a subsequent meal in frequently feeding sharks, which may be advantageous for exploiting resources that are spatially and temporally unpredictable. PMID:17280858

  6. Fast Maximum-Likelihood Decoder for Quasi-Orthogonal Space-Time Block Code

    Adel Ahmadi; Siamak Talebi

    2015-01-01

    Motivated by the decompositions of sphere and QR-based methods, in this paper we present an extremely fast maximum-likelihood (ML) detection approach for quasi-orthogonal space-time block code (QOSTBC). The proposed algorithm with a relatively simple design exploits structure of quadrature amplitude modulation (QAM) constellations to achieve its goal and can be extended to any arbitrary constellation. Our decoder utilizes a new decomposition technique for ML metric which divides the metric in...

  7. Time dependent solutions of the Fokker-Planck equation for fast fusion ions

    Approximate time dependent solutions for the Fokker-Planck equation for fast fusion ions from an isotropic, monoenergetic source are presented, for the problem of D - T - He3 reactions. The equations include the effect of diffusion, which is particularly noticeable in the distribution of particles of lower energy and in the formation of a tail of particles with energy higher than that of the source. (Author)

  8. Study on influence of ratio between wideness and height of EMP simulator transmission line with fast rise-time to rise-time of EMP

    The relation of rise-time inner EMP simulator with fast rise-time and ratio between wideness and height of simulator transmission line is studied through calculation of inner field of EMP simulator with fast rise-time and monadic linear regression analysis using FEKO based on MoM. The results indicate that there is close positive correlation between rise-time of EMP simulator with fast rise-time and the ratio between wideness and height. In other words, the larger the ratio of transmission line between wideness and height becomes, the longer the rise-time becomes. (authors)

  9. The effect of space charge in fast photomultipliers on the time resolution of liquid scintillators

    This paper reports on the effect of space charge and the inter dynodes parasitic component in fast photomultipliers on the time resolution of liquid scintillators investigated using strongly time correlated Gamma rays from 60Co and 22Na sources. For 52 mm diameter THORN-EMI photomultiplier model No.9815B, coupled to a 50 mm diameter NE213 cell, an improvement of 14% and 21% in time resolution is achieved after minimizing the space charge effects. A further improvement of 13% is obtained in time resolution for 60 Co and 22Na sources if sixth dynode signal is used instead of anode signal for timing analysis. For the 130 mm diameter THORN-EMI photomultiplier model No. 9823B coupled to 125 mm diameter NE213 cell, the influence of space charge on the time resolution of the detector is insignificant. However and improvement of 4 - 10% is obtained using sixth dynode signal

  10. Fast Time-Varying Volume Rendering Using Time-Space Partition (TSP) Tree

    Shen, Han-Wei; Chiang, Ling-Jen; Ma, Kwan-Liu

    1999-01-01

    We present a new, algorithm for rapid rendering of time-varying volumes. A new hierarchical data structure that is capable of capturing both the temporal and the spatial coherence is proposed. Conventional hierarchical data structures such as octrees are effective in characterizing the homogeneity of the field values existing in the spatial domain. However, when treating time merely as another dimension for a time-varying field, difficulties frequently arise due to the discrepancy between the field's spatial and temporal resolutions. In addition, treating spatial and temporal dimensions equally often prevents the possibility of detecting the coherence that is unique in the temporal domain. Using the proposed data structure, our algorithm can meet the following goals. First, both spatial and temporal coherence are identified and exploited for accelerating the rendering process. Second, our algorithm allows the user to supply the desired error tolerances at run time for the purpose of image-quality/rendering-speed trade-off. Third, the amount of data that are required to be loaded into main memory is reduced, and thus the I/O overhead is minimized. This low I/O overhead makes our algorithm suitable for out-of-core applications.

  11. A fast real time time-dependent density functional theory simulation method

    Wang, Lin-Wang; Wang, Zhi; Li, Shu-Sheng

    2015-03-01

    We have developed an efficient real-time time-dependent density functional theory (TDDFT) method that can increase the effective time step from traditional methods to 0.1 0.5 femtosecond. Our algorithm, which carries out the non-adiabatic molecular dynamics TDDFT simulations, can have comparable speed to the Born-Oppenheimer (BO) ab initio molecular dynamics (MD). As an application, we simulated the process of an energetic Cl particle colliding onto a monolayer of MoSe2. Our simulations show a significant energy transfer from the kinetic energy of the Cl particle to the electronic energy of MoSe2, and the result of TDDFT is very different from that of BO MD simulations. This new algorithm will enable the use of real-time TD-DFT for many new simulations involving carrier dynamics and electron-phonon couplings. This work is supported by the Director, Office of Science, BES/MSED, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231, through the Material Theory program in LBNL. Zhi Wang is supported by the China Scholarship Council.

  12. Corporate social responsibility approaches and implementation in selected fast food restaurants

    Emma E. Montalbo

    2015-01-01

    This study sought to determine Corporate Social Responsibility approaches and implementation in Fast Food Restaurants in Batangas City, Philippines. The researchers employed a descriptive design and quantitative method in the analysis of data with the questionnaire as the main instrument. Five (5) restaurant- participants were purposively chosen from the total population of 15. Results showed that CSR related mission/vision is clearly not embedded in the institutional websites ...

  13. Observation of very fast response signals from Pb absorber coupled transition edge sensor gamma-ray microcalorimeter

    Damayanthi, R.M.T., E-mail: thushara@sophie.q.t.u-tokyo.ac.jp [Department of Nuclear Engineering and Management, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Ohno, M.; Hatakeyama, S.; Takahashi, H. [Department of Nuclear Engineering and Management, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Maehata, K.; Yasumune, T.; Iyomoto, N. [Department of Applied Quantum Physics and Nuclear Engineering, Kyushu University, Motooka, Nishi-ku, Fukuoka 819-0395 (Japan)

    2012-11-01

    We are developing a gamma-ray microcalorimeter for Positron Annihilation Spectroscopy. Our detector composed of a transition edge sensor (TES) thermometer and an epoxy coupled bulk Pb absorber has been reported an energy resolution of 4.7 keV FWHM at 662 keV with a tens of milliseconds long response time. To enhance the detector properties, we designed a new attachment method in the focus of improving the thermal coupling between the absorber and the TES. In the new design, we created epoxy-posts both on the TES film and on the absorber, and then they were connected together using an epoxy-dot put on the epoxy-post on the absorber. Measured current signal of this epoxy-post TES gamma-ray detector showed an ultra fast response with 80 {mu}s fall time.

  14. 3-D seismic response of a base-isolated fast reactor

    This paper describes a 3-D response analysis methodology development and its application to a base-isolated fast breeder reactor (FBR) plant. At first, studies on application of a base-isolation system to an FBR plant were performed to identify a range of appropriate characteristics of the system. A response analysis method was developed based on mathematical models for the restoring force characteristics of several types of the systems. A series of shaking table tests using a small scale model was carried out to verify the analysis method. A good agreement was seen between the test and analysis results in terms of the horizontal and vertical responses. Parametric studies were then made to assess the effects of various factors which might be influential to the seismic response of the system. Moreover, the method was applied to evaluate three-dimensional response of the base-isolated FBR. (author)

  15. Holographic polymer networks formed in liquid crystal phase modulators via a He-Ne laser to achieve ultra-fast optical response.

    Chien, Chun-Yu; Hsu, Che-Ju; Chen, Yu-Wen; Tseng, Sheng-Hao; Sheu, Chia-Rong

    2016-04-01

    The holographic polymer network formed in liquid crystal (LC) phase modulators via a He-Ne laser in this study demonstrates ultra-fast optically response and low light scattering. These advantages are mainly caused by the small LC domains and uniform polymer network when processing LC cells via holographic exposure to a He-Ne laser. The use of this method to fabricate LC cells as phase modulators results in a decay time of 49 μs under 2π phase modulation at room temperature. The predicted fast optical response can be achieved when operating devices at high temperatures. PMID:27137042

  16. Effect of fasting on the metabolic response of liver to experimental burn injury.

    Mehmet A Orman

    Full Text Available Liver metabolism is altered after systemic injuries such as burns and trauma. These changes have been elucidated in rat models of experimental burn injury where the liver was isolated and perfused ex vivo. Because these studies were performed in fasted animals to deplete glycogen stores, thus simplifying quantification of gluconeogenesis, these observations reflect the combined impact of fasting and injury on liver metabolism. Herein we asked whether the metabolic response to experimental burn injury is different in fed vs. fasted animals. Rats were subjected to a cutaneous burn covering 20% of the total body surface area, or to similar procedures without administering the burn, hence a sham-burn. Half of the animals in the burn and sham-burn groups were fasted starting on postburn day 3, and the others allowed to continue ad libitum. On postburn day 4, livers were isolated and perfused for 1 hour in physiological medium supplemented with 10% hematocrit red blood cells. The uptake/release rates of major carbon and nitrogen sources, oxygen, and carbon dioxide were measured during the perfusion and the data fed into a mass balance model to estimate intracellular fluxes. The data show that in fed animals, injury increased glucose output mainly from glycogen breakdown and minimally impacted amino acid metabolism. In fasted animals, injury did not increase glucose output but increased urea production and the uptake of several amino acids, namely glutamine, arginine, glycine, and methionine. Furthermore, sham-burn animals responded to fasting by triggering gluconeogenesis from lactate; however, in burned animals the preferred gluconeogenic substrate was amino acids. Taken together, these results suggest that the fed state prevents the burn-induced increase in hepatic amino acid utilization for gluconeogenesis. The role of glycogen stores and means to increase and/or maintain internal sources of glucose to prevent increased hepatic amino acid

  17. Fast neutron measurements at the nELBE time-of-flight facility

    Junghansa A. R.

    2015-01-01

    Full Text Available The compact neutron-time-of-flight facility nELBE at the superconducting electron accelerator ELBE of Helmholtz-Zentrum Dresden-Rossendorf has been rebuilt. A new enlarged experimental hall with a flight path of up to 10 m is available for neutron time-of-flight experiments in the fast energy range from about 50 keV to 10 MeV. nELBE is intended to deliver nuclear data of fast neutron nuclear interactions e.g. for the transmutation of nuclear waste and improvement of neutron physical simulations of innovative nuclear systems. The experimental programme consists of transmission measurements of neutron total cross sections, elastic and inelastic scattering cross section measurements, and neutron induced fission cross sections. The inelastic scattering to the first few excited states in 56Fe was investigated by measuring the gamma production cross section with an HPGe detector. The neutron induced fission of 242Pu was studied using fast ionisation chambers with large homogeneous actinide deposits.

  18. Preparation and properties of fast temperature-responsive soy protein/PNIPAAm IPN hydrogels

    Liu Yong

    2014-01-01

    Full Text Available The interpenetrating polymer network of fast temperature-responsive hydrogels based on soy protein and poly(N-isopropylacrylamide were successfully prepared using the sodium bicarbonate (NaHCO3 solutions as the reaction medium. The structure and properties of the hydrogels were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry and thermal gravimetric analysis. The swelling and deswelling kinetics were also investigated in detail. The results have shown that the proposed hydrogels had high porous structure, good miscibility and thermal stability, and fast temperature responsivity. The presence of NaHCO3 had little effect on the volume phase transition temperature (VPTT of the hydrogels, and the VPTTs were at about 32°C. Compared with the traditional hydrogels, the proposed hydrogels had much faster swelling and deswelling rate. The swelling mechanism of the hydrogels was the non-Fickian diffusion. This fast temperature-responsive hydrogels may have potential applications in the field of biomedical materials.

  19. Corporate social responsibility approaches and implementation in selected fast food restaurants

    Emma E. Montalbo

    2015-08-01

    Full Text Available This study sought to determine Corporate Social Responsibility approaches and implementation in Fast Food Restaurants in Batangas City, Philippines. The researchers employed a descriptive design and quantitative method in the analysis of data with the questionnaire as the main instrument. Five (5 restaurant- participants were purposively chosen from the total population of 15. Results showed that CSR related mission/vision is clearly not embedded in the institutional websites of fast food restaurants while personal relation/social proximity approach is highly evident. Also, factors in the implementation of corporate social responsibility in relation to philanthropic behavior, shows a significant behavioral change from the statistical result such as moderately evident. CSR approaches and implementation are highly evident that clearly proves the responsible behavior of local fast food restaurants. Institutional integration of CSR in the company’s mission/vision statements, structure, decisions, activities, communication, practices stated appears to be beneficial in light of new corporate-state-market-society relationship.

  20. Fast neutron flux analyzer with real-time digital pulse shape discrimination

    Ivanova, A. A.; Zubarev, P. V.; Ivanenko, S. V.; Khilchenko, A. D.; Kotelnikov, A. I.; Polosatkin, S. V.; Puryga, E. A.; Shvyrev, V. G.; Sulyaev, Yu. S.

    2016-08-01

    Investigation of subthermonuclear plasma confinement and heating in magnetic fusion devices such as GOL-3 and GDT at the Budker Institute (Novosibirsk, Russia) requires sophisticated equipment for neutron-, gamma- diagnostics and upgrading data acquisition systems with online data processing. Measurement of fast neutron flux with stilbene scintillation detectors raised the problem of discrimination of the neutrons (n) from background cosmic particles (muons) and neutron-induced gamma rays (γ). This paper describes a fast neutron flux analyzer with real-time digital pulse-shape discrimination (DPSD) algorithm FPGA-implemented for the GOL-3 and GDT devices. This analyzer was tested and calibrated with the help of 137Cs and 252Cf radiation sources. The Figures of Merit (FOM) calculated for different energy cuts are presented.

  1. INFLUENCE OF RAMADAN FASTING ON ANAEROBIC PERFORMANCE AND RECOVERY FOLLOWING SHORT TIME HIGH INTENSITY EXERCISE

    Umid Karli

    2007-12-01

    Full Text Available The aim of this study was to investigate the effects of Ramadan fasting on anaerobic power and capacity and the removal rate of lactate after short time high intensity exercise in power athletes. Ten male elite power athletes (2 wrestlers, 7 sprinters and 1 thrower, aged 20-24 yr, mean age 22.30 ± 1.25 yr participated in this study. The subjects were tested three times [3 days before the beginning of Ramadan (Pre-RF, the last 3 days of Ramadan (End-RF and the last 3 days of the 4th week after the end of Ramadan (After-RF]. Anaerobic power and capacity were measured by using the Wingate Anaerobic Test (WAnT at Pre-RF, End-RF and After- RF. Capillary blood samples for lactate analyses and heart rate recordings were taken at rest, immediately after WAnT and throughout the recovery period. Repeated measures of ANOVA indicated that there were no significant changes in body weight, body mass index, fat free mass, percentage of body fat, daily sleeping time and daily caloric intake associated with Ramadan fasting. No significant changes were found in total body water either, but urinary density measured at End-RF was significantly higher than After-RF. Similarity among peak HR and peak LA values at Pre-RF, End- RF and After-RF demonstrated that cardiovascular and metabolic stress caused by WAnT was not affected by Ramadan fasting. In addition, no influence of Ramadan fasting on anaerobic power and capacity and removal rate of LA from blood following high intensity exercise was observed. The results of this study revealed that if strength-power training is performed regularly and daily food intake, body fluid balance and daily sleeping time are maintained as before Ramadan, Ramadan fasting will not have adverse effects on body composition, anaerobic power and capacity, and LA metabolism during and after high intensity exercise in power athletes

  2. Fast neutron response of LiF T.L. dosimeters

    Generally, the intensity of the main dosimetric peak i.e. the sensitivity of the most thermoluminescence (T.L.) dosimeters (expressed as the T.L. response/absorbed dose) decreases with increasing Let. However, it is known that the 'high temperature peak' (H.T.P.) of LiF:Mg,Ti T.L. detectors increases with increasing Let, while the 'low temperature peak' (L.T.P.) of LiF:Mg,Ti decreases. H.T.P., also called peak 7, appears between 240- 270 Celsius degrees, while L.T.P. can be found in the literature as peak 5 or 'dosimetric' peak and appears in the temperature range 180 -240 Celsius degrees. The dose response results of L.T.P. and H.T.P. of LiF:Mg,Ti in the literature are ambiguous in high Let radiation field. The reason in most cases is that the gamma component in the mixed field is not taken properly into consideration. In the every day practice work place monitoring it is necessary to measure low Let (gamma) and both low and high Let (e.g. gamma-neutron) radiation in the mixed fields. T.L.D. -100 (Harshaw) and M.T.S.-N (Poland) LiF:Mg,Ti dosimeters produced from natural LiF are easily available and widely used in the practical dosimetry tasks. The aim of this study was to compare the Let sensitivity of L.T.P. and H.T.P. for T.L.D.-100 (Harshaw) and M.T.S.-N (Poland) LiF detectors for 14.5 MeV neutrons in the dose range 50 mGy-300 mGy (expressed in tissue kerma). At the same time the effect of the holder type to the dosimeter response was also studied. 14.5 MeV fast neutrons produced by Texas Nuclear Corporation 300 keV electrostatic accelerator using 3 H(d,n)4 He nuclear reaction was used for neutron irradiation. The gamma component in the mixed field was measured by Geiger-Mueller counter calibrated in standard dosimetry laboratory. Gamma irradiation was carried out by 137Cs source. It was found, that while the gamma sensitivity of M.T.S. -N compared to T.L.D.-100 is about 2.5, the fast neutron sensitivity is much lower,equal to about 0.7. The responses of the

  3. A novel method for fast Change-Point detection on simulated time series and electrocardiogram data.

    Jin-Peng Qi

    Full Text Available Although Kolmogorov-Smirnov (KS statistic is a widely used method, some weaknesses exist in investigating abrupt Change Point (CP problems, e.g. it is time-consuming and invalid sometimes. To detect abrupt change from time series fast, a novel method is proposed based on Haar Wavelet (HW and KS statistic (HWKS. First, the two Binary Search Trees (BSTs, termed TcA and TcD, are constructed by multi-level HW from a diagnosed time series; the framework of HWKS method is implemented by introducing a modified KS statistic and two search rules based on the two BSTs; and then fast CP detection is implemented by two HWKS-based algorithms. Second, the performance of HWKS is evaluated by simulated time series dataset. The simulations show that HWKS is faster, more sensitive and efficient than KS, HW, and T methods. Last, HWKS is applied to analyze the electrocardiogram (ECG time series, the experiment results show that the proposed method can find abrupt change from ECG segment with maximal data fluctuation more quickly and efficiently, and it is very helpful to inspect and diagnose the different state of health from a patient's ECG signal.

  4. Fast silicon photomultiplier improves signal harvesting and reduces complexity in time-domain diffuse optics.

    Mora, Alberto Dalla; Martinenghi, Edoardo; Contini, Davide; Tosi, Alberto; Boso, Gianluca; Durduran, Turgut; Arridge, Simon; Martelli, Fabrizio; Farina, Andrea; Torricelli, Alessandro; Pifferi, Antonio

    2015-06-01

    We present a proof of concept prototype of a time-domain diffuse optics probe exploiting a fast Silicon PhotoMultiplier (SiPM), featuring a timing resolution better than 80 ps, a fast tail with just 90 ps decay time-constant and a wide active area of 1 mm2. The detector is hosted into the probe and used in direct contact with the sample under investigation, thus providing high harvesting efficiency by exploiting the whole SiPM numerical aperture and also reducing complexity by avoiding the use of cumbersome fiber bundles. Our tests also demonstrate high accuracy and linearity in retrieving the optical properties and suitable contrast and depth sensitivity for detecting localized inhomogeneities. In addition to a strong improvement in both instrumentation cost and size with respect to legacy solutions, the setup performances are comparable to those of state-of-the-art time-domain instrumentation, thus opening a new way to compact, low-cost and high-performance time-resolved devices for diffuse optical imaging and spectroscopy. PMID:26072763

  5. ABP1: An auxin receptor for fast responses at the plasma membrane

    Dahlke, Renate I.; Luethen, Hartwig; Steffens, Bianka

    2010-01-01

    Auxin-binding protein 1 (ABP1) is an auxin receptor for responses not primarily regulated by gene regulation. One fast response is protoplast swelling. By using immunological ABP1 tools we showed that the highly conserved box a is not alone important for auxin binding. Box c is another part of the auxin binding domain.1 Here we present a novel method to analyze auxin-induced, ABP1-mediated effects at the plasma membrane on single cell level in vivo. The fluorescence of FM4-64 in the plasma me...

  6. TRANC – a novel fast-response converter to measure total reactive atmospheric nitrogen

    O. Marx

    2011-12-01

    Full Text Available The input and loss of plant available nitrogen (N from/to the atmosphere can be an important factor for the productivity of ecosystems and thus for its carbon and greenhouse gas exchange. We present a novel converter for the measurement of total reactive nitrogen (TRANC: Total Reactive Atmospheric Nitrogen Converter, which offers the opportunity to quantify the sum of all airborne reactive nitrogen (Nr compounds in high time resolution. The basic concept of the TRANC is the full conversion of total Nr to nitrogen monoxide (NO within two reaction steps. Initially, reduced N compounds are being oxidised, and oxidised N compounds are thermally converted to lower oxidation states. Particulate N is being sublimated and oxidised or reduced afterwards. In a second step, remaining higher N oxides or those originated in the first step are catalytically converted to NO with carbon monoxide used as reduction gas. The converter is combined with a fast response chemiluminescence detector (CLD for NO analysis and its performance was tested for the most relevant gaseous and particulate Nr species under both laboratory and field conditions. Recovery rates during laboratory tests for NH3 and NO2 were found to be 95 and 99%, respectively, and 97% when the two gases were combined. In-field longterm stability over an 11-month period was approved by a value of 91% for NO2. Effective conversion was also found for ammonium and nitrate containing particles. The recovery rate of total ambient Nr was tested against the sum of individual measurements of NH3, HNO3, HONO, NH4+, NO3, and NOx using a combination of different well-established devices. The results show that the TRANC-CLD system precisely captures fluctuations in Nr concentrations and also matches the sum of all

  7. Fast self paced listening times in syntactic comprehension is aphasia -- implications for deficits

    Jennifer Michaud

    2015-04-01

    (the DV against corrected self paced listening times in the corresponding words in the baseline sentences (the IV in correct responses. We call the residuals of these regressions “relative corrected listening times.” Relative corrected listening times are based on listening times at points at which task-related operations are similar, and therefore factor out these effects. They also factor out differences in general speed of processing and motor functioning, which determine the intercepts of the regressions. The relative corrected listening times for each participant therefore reflect the time taken by each pwa or control participant to perform the parsing and interpretation operations needed in the experimental sentences, compared to the time taken by the other controls or pwa. We performed these regressions separately in each of the four groups of sentences. We analyzed pwa and controls separately. We analyzed groups and not individuals, because performing these regressions on an individual basis would lead to a mean residual for an experimental sentence type compared to a baseline sentence type that approximates zero in each individual (this is a property of linear regression. We analyzed controls and pwa separately to produce separate estimates of basic speed of processing, decision-making and other processes in controls and pwa. We calculated the normal range of relative corrected listening times for each sentence type group by applying the formula in Crawford and Howell (1998 to the results of the regressions in the controls. We then determined whether the relative corrected listening time for each group of sentences in each pwa was within the normal range of residuals. We focus on a finding that has not previously been reported, which is that, in some pwa, some relative corrected listening times (i.e., residuals of the regression of critical words in experimental sentences against corresponding words in baseline sentences were lower than those seen in

  8. TimepixCam: a fast optical imager with time-stamping

    We describe a novel fast optical imager, TimepixCam, based on an optimized silicon pixel sensor with a thin entrance window, read out by a Timepix ASIC. TimepixCam is able to record and time-stamp light flashes in excess of 1,000 photons with high quantum efficiency in the 400–1000nm wavelength range with 20ns timing resolution, corresponding to an effective rate of 50 Megaframes per second. The camera was used for imaging ions impinging on a microchannel plate followed by a phosphor screen. Possible applications include spatial and velocity map imaging of ions in time-of-flight mass spectroscopy; coincidence imaging of ions and electrons, and other time-resolved types of imaging spectroscopy

  9. Wavelet-based fast time-resolved magnetic sensing with electronic spins in diamond

    Xu, Nanyang; Jiang, Fengjian; Tian, Yu; Ye, Jianfeng; Shi, Fazhan; Lv, Haijiang; Wang, Ya; Wrachtrup, Jörg; Du, Jiangfeng

    2016-04-01

    Time-resolved magnetic sensing is of great importance from fundamental studies to applications in physical and biological sciences. Recently, the nitrogen-vacancy defect center in diamond has been developed as a promising sensor of magnetic fields under ambient conditions. However, methods to reconstruct time-resolved magnetic fields with high sensitivity are not yet fully developed. Here, we propose and demonstrate a sensing method based on spin echo and Haar wavelet transformation. Our method is exponentially faster in reconstructing time-resolved magnetic fields with comparable sensitivity than existing methods. It is also easier to implement in experiments. Furthermore, the wavelet's unique features enable our method to extract information from the whole signal with only part of the measuring sequences. We then explore this feature for a fast detection of simulated nerve impulses. These results will be useful to time-resolved magnetic sensing with quantum probes at nanoscale.

  10. Large-area fast-timing detectors developed for the TOFI spectrometer

    Large-area fast-timing detectors have been developed for use in the TOFI spectrometer. A gridless detector was constructed in which secondary electrons emitted from a thin (≅ 80 μg/cm2) target foil were transported isochronously to microchannel plate electron multipliers by crossed electric and magnetic fields. A novel convex anode was designed to reduce the time dispersion caused by the position at which the secondary electrons were collected. Timing performance for aluminium oxide target foils was found to be superior to that of carbon foils. Intrinsic timing resolutions of 68 and 109 ps fwhm have been measured for 5.4 MeV alpha particles from a thin 241Am source for two different detectors with active areas of 270 and 1000 mm2, respectively. Detection efficiencies in excess of 75% for alpha particles were measured. (orig.)

  11. Development of a LaBr3(Ce Fast-timing Array for FAIR

    Roberts O.J.

    2013-12-01

    Full Text Available A γ-ray spectrometer with fast-timing capabilities, constructed of LaBr3(Ce:5% detectors, is under development for use at the future Facility for Anti-proton and Ion Research (FAIR. The physics aims of this device are to measure the half-lives of excited states in the region of ~50 ps to several ns, in exotic nuclei. Monte-Carlo simulations using the GEANT4 software package have determined the final design of this fast-timing array by calculating the full-energy peak efficiencies of several different detector geometries. The results of the simulated efficiencies for each configuration were used to calculate the timing precision. Consequently, an array of thirty six, ø3.8×5.1 cm cylindrical crystals was found to be the optimum configuration. The detectors were purchased and subsequently characterised, with each detector found to have intrinsic energy and timing resolutions of ~ 2.8 % (FWHM and ~ 210 ps (FWHM for the 1173 and 1332 keV decays from 60Co.

  12. Development of a LaBr3(Ce) Fast-timing Array for FAIR

    A γ-ray spectrometer with fast-timing capabilities, constructed of LaBr3(Ce:5%) detectors, is under development for use at the future Facility for Anti-proton and Ion Research (FAIR). The physics aims of this device are to measure the half-lives of excited states in the region of ∼50 ps to several ns, in exotic nuclei. Monte-Carlo simulations using the GEANT4 software package have determined the final design of this fast-timing array by calculating the full-energy peak efficiencies of several different detector geometries. The results of the simulated efficiencies for each configuration were used to calculate the timing precision. Consequently, an array of thirty six, section 3.8 x 5.1 cm cylindrical crystals was found to be the optimum configuration. The detectors were purchased and subsequently characterised, with each detector found to have intrinsic energy and timing resolutions of ∼ 2.8 % (FWHM) and ∼ 210 ps (FWHM) for the 1173 and 1332 keV decays from 60Co. (authors)

  13. Fast response Fabry-Perot interferometer microfluidic refractive index fiber sensor based on concave-core photonic crystal fiber.

    Tian, Jiajun; Lu, Zejin; Quan, Mingran; Jiao, Yuzhu; Yao, Yong

    2016-09-01

    We report a fast response microfluidic Fabry-Perot (FP) interferometer refractive index (RI) fiber sensor based on a concave-core photonic crystal fiber (CPCF), which is formed by directly splicing a section CPCF with a section of single mode fiber. The CPCF is made by cleaving a section of multimode photonic crystal fiber with an axial tension. The shallow concave-core of CPCF naturally forms the FP cavity with a very short cavity length. The inherent large air holes in the cladding of CPCF are used as the open channels to let liquid sample come in and out of FP cavity. In order to shorten the liquid channel length and eliminate the harmful reflection from the outside end face of the CPCF, the CPCF is cleaved with a tilted tensile force. Due to the very small cavity capacity, the short length and the large sectional area of the microfluidic channels, the proposed sensor provides an easy-in and easy-out structure for liquids, leading to great decrement of the measuring time. The proposed sensor exhibits fast measuring speed, the measuring time is less than 359 and 23 ms for distilled water and pure ethanol, respectively. We also experimentally study and demonstrate the superior performances of the sensor in terms of high RI sensitivity, good linear response, low temperature cross-sensitivity and easy fabrication. PMID:27607621

  14. Effects of Ramadan on physical capacities of North African boys fasting for the first time

    Mohamed A. Fenneni

    2014-09-01

    Full Text Available Introduction: Most of the literature related to the effects of Ramadan fasting on physical performance has focused on adults, and only three studies have examined its impact on children's physical performance. Aims: To examine the effects of Ramadan fasting on first-time fasting boys’ performance in short-term explosive exercises [vertical and horizontal jump tests (VJT and HJT, 20-m and 30-m sprints and medicine-ball throw (MBT], as well as in sub-maximal endurance [6-min walking distance (6MWD measured during the 6-min walk test (6MWT]. Methods: Eighteen Tunisian boys [mean±standard deviation (SD of age and body mass (BM: 11.9±0.8 y and 55.4±18.2 kg, respectively] were included. The experimental design comprised four testing phases: 2-weeks before Ramadan (BR, the end of the second week (R2 and the fourth week (R4 of Ramadan, and 10–12 days after the end of Ramadan (AR. At each phase, boys performed two test sessions in the afternoon (15:00–17:00 h interrupted by 48 h of recovery (first test session: BM, VJT, HJT, and 20-m and 30-m sprint tests; second session: MBT and 6MWT. The study was conducted during the summer of 2012 from July 5 to August 29. Results: 6MWDs (m were significantly shorter during R2 (652±101 and R4 (595±123 compared to BR (697±86 and came back to baseline values AR. BM (kg mean±SD did not significantly change during R2 (52±15 and during R4 (53±15 compared to BR (55±17, and short-term explosive performances were unchanged throughout the study. Conclusion: In non-athletic children, first-ever Ramadan fasting impairs sub-maximal aerobic capacity but has no effect on BM or short-term explosive performance.

  15. Optimization of Jiawei Qing'e Oral Fast Disintegrating Tablets Based on Response Surface-Central Composite Design

    ZHANG Wei-ling; WANG Ya-jing; GAO Xiu-mei; GAO Xu; PENG Shu-juan; ZHENG Yin; OKEKE Chukwunweike Ikechukwu

    2013-01-01

    Objective To apply the response surface-central composite design to developing and optimizing the oral fast disintegrating tablets (ODT) formulation for Jiawei Qing'e,a kind of prescription of Chinese herbal medicine.Methods The bitterness of Jiawei Qing'e was masked using Eudragit E-100 by solvent evaporation technique.Response surface approach was applied to investigating the interaction of formulation parameters in optimizing the formulation.The independent variables were Eudragit E-100/drug ratio (X1),amount of disintegrants (X2),and the amount of diluents (X3).The disintegration time (Y1),hardness (Y2),and weight variations of the tablets were characterized.Results The models predicted levels ofX1 =4.63%,X2 =5.25%,and X3 =34.33%,for the optimal formulation having a hardness of 3.0 kg with the disintegration time of 30 s within experimental region.The observed response of Y1 =26.5 s and Y2 =3.14 kg reasonably agreed with the predicted response.Conclusion Response surface methodology shows the good predictability and reliability in optimizing the formulation.The optimized ODT of Jiawei Qing'e has acceptable taste,rapid disintegrating ability,and good mechanical strength.

  16. Fast time resolution measurements of high concentrations of iodine above a Laminaria Digitata seaweed bed

    Ball, Stephen; Adams, Thomas; Leblanc, Catherine; Potin, Philippe

    2013-04-01

    -distant seaweeds whose emissions are better-mixed into the atmosphere. The peak I2 concentrations observed here are three to five times greater than the maximum amounts recorded above/closeby laminaria beds in previous studies: 350 pptv max in O Grove, Galicia, Spain (Mahajan et al., ACP, 11, 2545, 2011), and 302 and 547 pptv max at Mweenish Bay, near Mace Head, County Galway, Ireland (Huang et al., GRL, 37, L03803, 2010; ACPD, 12, 25915, 2012). In part, the larger peak concentrations seen here are a consequence of deploying a fast response instrument very close to the source, enabling the emission's high temporal variability to be captured with fewer averaging effects. Nevertheless, the I2 concentrations averaged over the 30 minute period around the tidal minimum were still typically 750 pptv, suggesting laminaria beds are even stronger emitters of I2 into coastal atmospheres than previously thought. Some implications for such high concentrations of iodine for the local atmospheric chemistry are considered. We acknowledge support from the European Community FP7 project "ASSEMBLE", grant 227799.

  17. The arrival direction of energetic cosmic rays measured with a fast timing Cerenkov light technique

    The accurate arrival directions of air showers (0) available from a fast timing Cerenkov light experiment are used to search for point sources of ultra high energy γ-rays. The data span the energy range 5 x 1015 eV - 1017 eV and were recorded in the period 1977-1980 at Dugway, Utah. Most of the exposure was of the Galactic anticentre region. Flux limits of approximately 10-13 to approximately 2 x 10-15 cm-2 sec-1 for primaries of energy >= 3 x 1015 to >=1017 eV from the Crab nebula have been determined

  18. Small-time asymptotics for fast mean-reverting stochastic volatility models

    Jin Feng; Jean-Pierre Fouque; Rohini Kumar

    2010-01-01

    In this paper, we study stochastic volatility models in regimes where the maturity is small, but large compared to the mean-reversion time of the stochastic volatility factor. The problem falls in the class of averaging/homogenization problems for nonlinear HJB-type equations where the "fast variable" lives in a noncompact space. We develop a general argument based on viscosity solutions which we apply to the two regimes studied in the paper. We derive a large deviation principle, and we dedu...

  19. Fast Tracker: a hardware real time track finder for the ATLAS trigger system

    The Fast Tracker (FTK) is an integral part of the trigger upgrade program of the ATLAS detector at the Large Hadron Collider (LHC). As the LHC luminosity approaches its design level of 1034 cm−2s−1, the combinatorial problem posed by charged particle tracking becomes increasingly difficult due to the swelling of multiple interactions per bunch crossing. The FTK is a highly-parallel hardware system intended to provide high-quality tracks with transverse momentum above 1 GeV in real time for online trigger system. The FTK system's design, based on a mixture of advanced technologies, and the expected physics performance will be presented

  20. The Response Time Analysis of Digital Broadcasting System

    WANG Shuo; ZHANG Jiang-ling; FENG Dan

    2005-01-01

    Digital broadcasting system has become a highlight of research on computer application. To respond to the changes of the playbill in the broadcasting system in real time, the response time of the system must be studied. There is scarcely the research on this area currently. The influence factors in the response time are analyzed; the model on the response time of the system service is built; how the influence factors affect the response time of the system service is validated; and four improvement measures are proposed to minimize the response time of system service.

  1. Fast elaboration of diagnostic data for real time control in FTU tokamak

    Nowak S.

    2012-09-01

    Full Text Available The automatic controller developed for MHD instability control on FTU via the real time (RT EC launcher [1, 2] is based on the a-priori estimate of the instabilities location and on the fast elaboration of the stream of diagnostic data. A fast data acquisition system, based on existing standard FTU diagnostics, collects thermal and magnetic signals by a 12-channels ECE polychromator [3] and by a set of 22 Mirnov coils respectively. Moreover, the EC time waveform from directional couplers along the transmission line is acquired as well. This set of signals is processed in a timescale significantly shorter than the typical time step of the controller (1ms. RT elaboration algorithms aim at supplying the controller [4] with reliable information about the existence and the spatial location of the instability and about the actual ECRH deposition layer in plasma. The main algorithms blocks are ECE-ECE, ECE-Mirnov and ECE-ECRH cross-correlation, and SVD (Singular Value Decomposition of Mirnov signals. The capabilities of effective detection, false positive resilience, and mode discrimination will be discussed through the application to actual plasma data.

  2. Beam test results of a 15 ps timing system based on ultra-fast silicon detectors

    Cartiglia, N; Sola, V; Arcidiacono, R; Cirio, R; Cenna, F; Ferrero, M; Monaco, V; Mulargia, R; Obertino, M; Ravera, F; Sacchi, R; Bellora, A; Durando, S; Mandurrino, M; Minafra, N; Fadeyev, V; Freeman, P; Galloway, Z; Gkougkousis, E; Grabas, H; Gruey, B; Labitan, C A; Losakul, R; McKinney-Martinez, F; Sadrozinski, H F -W; Seiden, A; Spencer, E; Wilder, M; Woods, N; Zatserklyaniy, A; Pellegrini, G; Hidalgo, S; Carulla, M; Flores, D; Merlos, A; Quirion, D; Cindro, V; Kramberger, G; Mandic, I; Mikuz, M; Zavrtanik, M

    2016-01-01

    In this paper we report on the timing resolution of the first production of 50 micro-meter thick Ultra-Fast Silicon Detectors (UFSD) as obtained in a beam test with pions of 180 GeV/c momentum. UFSD are based on the Low-Gain Avalanche Detectors (LGAD) design, employing n-on-p silicon sensors with internal charge multiplication due to the presence of a thin, low-resistivity diffusion layer below the junction. The UFSD used in this test belongs to the first production of thin (50 {\\mu}m) sensors, with an pad area of 1.4 mm2. The gain was measured to vary between 5 and 70 depending on the bias voltage. The experimental setup included three UFSD and a fast trigger consisting of a quartz bar readout by a SiPM. The timing resolution, determined comparing the time of arrival of the particle in one or more UFSD and the trigger counter, for single UFSD was measured to be 35 ps for a bias voltage of 200 V, and 26 ps for a bias voltage of 240 V, and for the combination of 3 UFSD to be 20 ps for a bias voltage of 200 V, ...

  3. Improving Adaptive Learning Technology through the Use of Response Times

    Mettler, Everett; Massey, Christine M.; Kellman, Philip J.

    2011-01-01

    Adaptive learning techniques have typically scheduled practice using learners' accuracy and item presentation history. We describe an adaptive learning system (Adaptive Response Time Based Sequencing--ARTS) that uses both accuracy and response time (RT) as direct inputs into sequencing. Response times are used to assess learning strength and…

  4. Fast and Accurate Computation of Time-Domain Acoustic Scattering Problems with Exact Nonreflecting Boundary Conditions

    Wang, Li-Lian; Zhao, Xiaodan

    2011-01-01

    This paper is concerned with fast and accurate computation of exterior wave equations truncated via exact circular or spherical nonreflecting boundary conditions (NRBCs, which are known to be nonlocal in both time and space). We first derive analytic expressions for the underlying convolution kernels, which allow for a rapid and accurate evaluation of the convolution with $O(N_t)$ operations over $N_t$ successive time steps. To handle the onlocality in space, we introduce the notion of boundary perturbation, which enables us to handle general bounded scatters by solving a sequence of wave equations in a regular domain. We propose an efficient spectral-Galerkin solver with Newmark's time integration for the truncated wave equation in the regular domain. We also provide ample numerical results to show high-order accuracy of NRBCs and efficiency of the proposed scheme.

  5. Technical Proposal for the ALICE START Fast Timing Detector Based on Fine-Mesh Phototubes

    Kaplin, V A; CERN. Geneva; Loginov, V A; Strikhanov, M N; Gavrilov, Yu K; Filippov, S N; Kurepin, A B; Mayevskaya, A I

    1997-01-01

    Technical Proposal for the ALICE START Fast Timing Detector Based on Fine-Mesh Phototubes A scintillation detector based on fine-mesh phototubes with good timing proporties ( ~ 50 ps) is proposed as a complementary detector for two existing options of the ALICE Forward Multiplicity Detector. Experimental results show high time resolution (up to 35 ps) and high gain in a magnetic field up to 0.5 T of fine-mesh Russian phototubes FEU-527. The proposed detector consists of two arrays of scintillation (or Cherenkov) counters, 24 counters each. The Monte-Carlo simulations made for the proposed design of the detector for p-p collisions give the average efficiency of the detector about 80%. The physical characteristics of the proposed detector are compared with those expected for the MCP version of the FMD.

  6. Proposed fast-response oxygen monitoring and control system for the Langley 8-foot high-temperature tunnel

    Singh, J. J.; Davis, W. T.; Puster, R. L.

    1983-01-01

    A fast-response oxygen monitoring and control system, based on a Y2O3-stabilized ZrO2 sensor, was developed and tested in the laboratory. The system is capable of maintaining oxygen concentration in the CH4-O2-air combustion product gases at 20.9 + or - 1.0 percent. If the oxygen concentration in the exhaust stream differs from that in normal air by 25 percent or more, an alarm signal is provided for automatic tunnel shutdown. The overall prototype system response time was reduced from about 1 sec in the original configuration to about 0.2 sec. The basis of operation and the results of laboratory tests of the system are described.

  7. Fast UV-Vis photorefractive response of Zr and Mg codoped LiNbO3:Mo.

    Tian, Tian; Kong, Yongfa; Liu, Shiguo; Li, Wei; Chen, Shaolin; Rupp, Romano; Xu, Jingjun

    2013-05-01

    A series of LN:Mo,Zr and LN:Mo,Mg crystals with different doping concentrations were grown and their holographic properties were investigated from UV to the visible range. Each crystal allows for holographic storage from UV to the visible as LN:Mo. When the concentration of MgO is enhanced to 6.5 mol%, the response time can be dramatically shortened to 0.22 s, 0.33 s, 0.37 s and 1.2 s for 351, 488, 532, and 671 nm laser, respectively. The results show that LN:Mo,Mg is a promising candidate for all-color holographic volume storage with fast response. PMID:23669902

  8. Using Graphs for Fast Error Term Approximation of Time-varying Datasets

    Nuber, C; LaMar, E C; Pascucci, V; Hamann, B; Joy, K I

    2003-02-27

    We present a method for the efficient computation and storage of approximations of error tables used for error estimation of a region between different time steps in time-varying datasets. The error between two time steps is defined as the distance between the data of these time steps. Error tables are used to look up the error between different time steps of a time-varying dataset, especially when run time error computation is expensive. However, even the generation of error tables itself can be expensive. For n time steps, the exact error look-up table (which stores the error values for all pairs of time steps in a matrix) has a memory complexity and pre-processing time complexity of O(n2), and O(1) for error retrieval. Our approximate error look-up table approach uses trees, where the leaf nodes represent original time steps, and interior nodes contain an average (or best-representative) of the children nodes. The error computed on an edge of a tree describes the distance between the two nodes on that edge. Evaluating the error between two different time steps requires traversing a path between the two leaf nodes, and accumulating the errors on the traversed edges. For n time steps, this scheme has a memory complexity and pre-processing time complexity of O(nlog(n)), a significant improvement over the exact scheme; the error retrieval complexity is O(log(n)). As we do not need to calculate all possible n2 error terms, our approach is a fast way to generate the approximation.

  9. System measures response time of photomultiplier tubes

    Lauver, M. R.

    1968-01-01

    Calibration system enables precise determination of rise time of photosensitive detectors. To perform a calibration, the time-voltage curve of the excitation voltage for a light source is compared with the time-voltage curve of the voltage output from a photosensitive detector which is responding to the light.

  10. The ITER Fast Plant System Controller ATCA prototype Real-Time Software Architecture

    Carvalho, B.B., E-mail: bernardo@ipfn.ist.utl.pt [Associacao EURATOM/IST Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, P-1049-001 Lisboa (Portugal); Santos, B.; Carvalho, P.F.; Neto, A. [Associacao EURATOM/IST Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, P-1049-001 Lisboa (Portugal); Boncagni, L. [Associazione Euratom-ENEA sulla Fusione, Frascati Research Centre, Division of Fusion Physics, Frascati, Rome (Italy); Batista, A.J.N.; Correia, M.; Sousa, J.; Gonçalves, B. [Associacao EURATOM/IST Instituto de Plasmas e Fusao Nuclear, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, P-1049-001 Lisboa (Portugal)

    2013-10-15

    Highlights: ► High performance ATCA systems for fast control and data acquisition. ► IEEE1588 timing system and synchronization. ► Plasma control algorithms. ► Real-time control software frameworks. ► Targeted for nuclear fusion experiments with long duration discharges. -- Abstract: IPFN is developing a prototype Fast Plant System Controller (FPSC) based in ATCA embedded technologies dedicated to ITER CODAC data acquisition and control tasks in the sub-millisecond range. The main goal is to demonstrate the usability of the ATCA standard and its enhanced specifications for the high speed, very high density parallel data acquisition needs of the most demanding ITER tokamak plasma Instrumentation and Control (I and C) systems. This effort included the in-house development of a new family of high performance ATCA I/O and timing boards. The standard ITER software system CODAC Core System (CCS) v3.1, with the control based in the EPICS system does not cover yet the real-time requirements fulfilled by this hardware, so a new set of software components was developed for this specific platform, attempting to integrate and leverage the new features in CSS, for example the Multithreaded Application Real Time executor (MARTe) software framework, the new Data Archiving Network (DAN) solution, an ATCA IEEE-1588-2008 timing interface, and the Intelligent Platform Management Interface (IPMI) for system monitoring and remote management. This paper presents the overall software architecture for the ATCA FPSC, as well a discussion on the ITER constrains and design choices and finally a detailed description of the software components already developed.

  11. The ITER Fast Plant System Controller ATCA prototype Real-Time Software Architecture

    Highlights: ► High performance ATCA systems for fast control and data acquisition. ► IEEE1588 timing system and synchronization. ► Plasma control algorithms. ► Real-time control software frameworks. ► Targeted for nuclear fusion experiments with long duration discharges. -- Abstract: IPFN is developing a prototype Fast Plant System Controller (FPSC) based in ATCA embedded technologies dedicated to ITER CODAC data acquisition and control tasks in the sub-millisecond range. The main goal is to demonstrate the usability of the ATCA standard and its enhanced specifications for the high speed, very high density parallel data acquisition needs of the most demanding ITER tokamak plasma Instrumentation and Control (I and C) systems. This effort included the in-house development of a new family of high performance ATCA I/O and timing boards. The standard ITER software system CODAC Core System (CCS) v3.1, with the control based in the EPICS system does not cover yet the real-time requirements fulfilled by this hardware, so a new set of software components was developed for this specific platform, attempting to integrate and leverage the new features in CSS, for example the Multithreaded Application Real Time executor (MARTe) software framework, the new Data Archiving Network (DAN) solution, an ATCA IEEE-1588-2008 timing interface, and the Intelligent Platform Management Interface (IPMI) for system monitoring and remote management. This paper presents the overall software architecture for the ATCA FPSC, as well a discussion on the ITER constrains and design choices and finally a detailed description of the software components already developed

  12. Design and evaluation of a device for fast multispectral time-resolved fluorescence spectroscopy and imaging

    The application of time-resolved fluorescence spectroscopy (TRFS) to in vivo tissue diagnosis requires a method for fast acquisition of fluorescence decay profiles in multiple spectral bands. This study focusses on development of a clinically compatible fiber-optic based multispectral TRFS (ms-TRFS) system together with validation of its accuracy and precision for fluorescence lifetime measurements. It also presents the expansion of this technique into an imaging spectroscopy method. A tandem array of dichroic beamsplitters and filters was used to record TRFS decay profiles at four distinct spectral bands where biological tissue typically presents fluorescence emission maxima, namely, 390, 452, 542, and 629 nm. Each emission channel was temporally separated by using transmission delays through 200 μm diameter multimode optical fibers of 1, 10, 19, and 28 m lengths. A Laguerre-expansion deconvolution algorithm was used to compensate for modal dispersion inherent to large diameter optical fibers and the finite bandwidth of detectors and digitizers. The system was found to be highly efficient and fast requiring a few nano-Joule of laser pulse energy and <1 ms per point measurement, respectively, for the detection of tissue autofluorescent components. Organic and biological chromophores with lifetimes that spanned a 0.8–7 ns range were used for system validation, and the measured lifetimes from the organic fluorophores deviated by less than 10% from values reported in the literature. Multi-spectral lifetime images of organic dye solutions contained in glass capillary tubes were recorded by raster scanning the single fiber probe in a 2D plane to validate the system as an imaging tool. The lifetime measurement variability was measured indicating that the system provides reproducible results with a standard deviation smaller than 50 ps. The ms-TRFS is a compact apparatus that makes possible the fast, accurate, and precise multispectral time-resolved fluorescence

  13. Exupéry - a mobile fast response system for managing a volcanic crisis

    Hort, M. K.

    2009-12-01

    Despite ever increasing efforts to monitor historically active volcanoes many of those are still very poorly or unmonitored, even in highly populated areas. In case of volcanic unrest or even a volcanic crisis evaluating the situation is therefore often very difficult due to the little information that is available for that specific volcano. Over the past decades several different programs have supported volcanic crisis management efforts in third world countries from sending experts all the way to improving or even installing new networks around the volcano. One of the main problems especially when quickly upgrading networks during a crisis is that each system usually comes with its own acquisition and processing system which makes it very difficult to manage the observational network and provide an interdisciplinary interpretation of the data with respect to the activity status of the volcano. Here we present a newly developed volcano fast response system which overcomes several of these shortcomings. The core of the system is a novel database (SEISHUB) that allows for the collection of data of various kinds, i.e. simple time series data like seismic data, gas measurements, GPS measurements, as well as satellite data (SO2 flux, thermal anomaly, ground deformation). Part of the collected data may also come from an already existing network. Data from new field instruments are transmitted through a wireless network that has been specifically designed for the volcano fast response system. One of the main difficulties with such a multidisciplinary data set is an easy access to the data. This is provided through a common Web based GIS interface which allows various datalayers being simultaneously accessed through a Web Browser. The underlying software is designed in such a way that it only uses open source software, so it can be easily installed on other systems not having to deal with purchasing proprietary software. Aside from this the system provides tools to

  14. An Ultralow Power Fast-Response Nano-TCD CH4 sensor for UAV Airborne Measurements Project

    National Aeronautics and Space Administration — In this project, KWJ proposes to develop a low power, fast response, lightweight miniature CH4 measurement system based on KWJ nano-TCD sensor for airborne...

  15. Limits on Fast Radio Bursts at 145 MHz with ARTEMIS, a real-time software backend

    Karastergiou, A; Armour, W; Williams, C; Mort, B; Dulwich, F; Salvini, S; Magro, A; Roberts, S; Serylak, M; Doo, A; Bilous, A V; Breton, R P; Falcke, H; Griessmeier, J -M; Hessels, J W T; Keane, E F; Kondratiev, V I; Kramer, M; van Leeuwen, J; Noutsos, A; Oslowski, S; Sobey, C; Stappers, B W; Weltevrede, P

    2015-01-01

    Fast Radio Bursts (FRBs), are millisecond radio signals that exhibit dispersion larger than what the Galactic electron density can account for. We have conducted a 1446 hour survey for Fast Radio Bursts (FRBs) at 145~MHz, covering a total of 4193 sq. deg on the sky. We used the UK station of the LOFAR radio telescope -- the Rawlings Array -- , accompanied for a majority of the time by the LOFAR station at Nan\\c{c}ay, observing the same fields at the same frequency. Our real-time search backend, ARTEMIS, utilizes graphics processing units to search for pulses with dispersion measures up to 320 cm$^{-3}$ pc. Previous derived FRB rates from surveys around 1.4~GHz, and favoured FRB interpretations, motivated this survey, despite all previous detections occurring at higher dispersion measures. We detected no new FRBs above a signal-to-noise threshold of 10, leading to the most stringent upper limit yet on the FRB event rate at these frequencies: 29 sky$^{-1}$ day$^{-1}$ for 5~ms-duration pulses above 62~Jy. The no...

  16. Time-resolved Fast Neutron Radiography of Air-water Two-phase Flows

    Zboray, Robert; Dangendorf, Volker; Mor, Ilan; Tittelmeier, Kai; Bromberger, Benjamin; Prasser, Horst-Michael

    Neutron imaging, in general, is a useful technique for visualizing low-Z materials (such as water or plastics) obscured by high-Z materials. However, when significant amounts of both materials are present and full-bodied samples have to be examined, cold and thermal neutrons rapidly reach their applicability limit as the samples become opaque. In such cases one can benefit from the high penetrating power of fast neutrons. In this work we demonstrate the feasibility of time-resolved, fast neutron radiography of generic air-water two-phase flows in a 1.5 cm thick flow channel with Aluminum walls and rectangular cross section. The experiments have been carried out at the high-intensity, white-beam facility of the Physikalisch-Technische Bundesanstalt, Germany. Exposure times down to 3.33 ms have been achieved at reasonable image quality and acceptable motion artifacts. Different two-phase flow regimes such as bubbly slug and churn flows have been examined. Two-phase flow parameters like the volumetric gas fraction, bubble size and bubble velocities have been measured.

  17. Time and space resolved interferometry for laser-generated fast electron measurements

    A technique developed to measure in time and space the dynamics of the electron populations resulting from the irradiation of thin solids by ultraintense lasers is presented. It is a phase reflectometry technique that uses an optical probe beam reflecting off the target rear surface. The phase of the probe beam is sensitive to both laser-produced fast electrons of low-density streaming into vacuum and warm solid density electrons that are heated by the fast electrons. A time and space resolved interferometer allows to recover the phase of the probe beam sampling the target. The entire diagnostic is computationally modeled by calculating the probe beam phase when propagating through plasma density profiles originating from numerical calculations of plasma expansion. Matching the modeling to the experimental measurements allows retrieving the initial electron density and temperature of both populations locally at the target surface with very high temporal and spatial resolution (∼4 ps,6 μm). Limitations and approximations of the diagnostic are discussed and analyzed.

  18. Design of responsive polymer surfaces with ultrafast response time

    Genzer, Jan; Ozcam, Evren; Willoughby, Julie

    2009-03-01

    Responsive surfaces with tailorable surface-reconstruction kinetics and switching hysteresis were prepared from poly(vinylmethylsiloxane) (PVMS) networks modified with thiol alkanes to provide hydrophobic or hydrophilic surface properties. The cooperative effects of polymer mobility, arising from the high flexibility of the siloxane backbone, and the enthalpic interactions between the contacting medium and the PVMS functionalized surface control the degree of responsiveness. Exposing the modified-elastomer surfaces to water resulted in rearrangement of the hydrophilic alkanes at the surface. The kinetics of reconstruction and reversibility were established by measuring the surface wettability via dynamic contact angle. By controlling the formation of semi-crystalline regions in our substrates we demonstrate either ``sluggish'' kinetics and eventual surface ``freezing'' and stability or stimuli-responsive substrates with a magnitude of change and repeated reversibility unparallel to most polymeric surfaces.

  19. High-ampacity conductive polymer microfibers as fast response wearable heaters and electromechanical actuators

    Zhou, Jian

    2016-01-04

    Conductive fibers with enhanced physical properties and functionalities are needed for a diversity of electronic devices. Here, we report very high performance in the thermal and mechanical response of poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS) microfibers when subjected to an electrical current. These fibers were made by combining the hot-drawing assisted wetspinning process with ethylene glycol doping/de-doping that can work at a current density as high as 1.8 × 104 A cm−2, which is comparable to that of carbon nanotube fibers. Their electrothermal response was investigated using optical sensors and verified to be as fast as 63 °C s−1 and is comparable with that of metallic heating elements (20–50 °C s−1). We investigated the electromechanical actuation resulted from the reversible sorption/desorption of moisture controlled by electro-induced heating. The results revealed an improvement of several orders of magnitudes compared to other linear conductive polymer-based actuators in air. Specifically, the fibers we designed here have a rapid stress generation rate (>40 MPa s−1) and a wide operating frequency range (up to 40 Hz). These fibers have several characteristics including fast response, low-driven voltage, good repeatability, long cycle life and high energy efficiency, favoring their use as heating elements on wearable textiles and as artificial muscles for robotics.

  20. A new fast friendly window-based congestion control for real-time streaming media transmission

    LI Yongli; LIU Guizhong; ZHANG Zhongwei; WU Chenggui

    2005-01-01

    Real-time streaming media over the Internet is an important component of multimedia applications. For the sake of quality of service (QoS), they make rigid demands on bandwidth, delay and packet loss. However, the current Internet does not offer any QoS guarantees to real-time streaming media over it. How to maximize the transmission quality of real-time streaming applications in a best-effort network while friendly sharing bandwidth with non-real time applications like TCP has become an important issue. But now, many real-time streaming applications based on UDP rarely perform congestion control in a TCP-friendly manner, and they do not share the available bandwidth fairly with applications built on TCP. The Internet communication strongly fears that the current evolution could lead to congestion collapse and starvation of TCP traffic. For this reason, TCP-friendly protocols are being developed to behave fairly with respect to coexistent TCP flows. In this paper we present a new window-based congestion control method-fast fair binomial congestion control (FFBCC) for real-time applications. It provides a good performance of bandwidth distribution and TCP-friendliness for real-time streaming transmission while competing bandwidth with TCP flows.

  1. Fast magnetic resonance imaging technology for time-series image diagnosis

    To expand the range of applicability of magnetic resonance imaging (MRI) tests, the Toshiba Group is engaged in the development of a time-series imaging technology with the aim of achieving double the acquisition speed compared with the conventional parallel imaging (PI) method. Although the PI method, which is the principal method used in existing products, can provide acquired images with approximately two or three times the spatial and/or temporal resolution through the integration of multiple coils and image processing technologies, it is not sufficient for time-series image diagnosis. A time-series PI method to increase the acceleration factors of PI requires and additional time-series map scan for calibration, hindering the improvement of imaging speed. In order to achieve a breakthrough in this situation, we are developing a fast MRI technology that can reconstruct images using the time-series PI method without the need for an additional time-series map scan. The resulting enhancement of the imaging speed will be useful in various areas, such as the acquisition of cardiac images with higher resolution. (author)

  2. Quasi-static reactivity balance interpretations of inherent safety response in fast and thermal reactors

    The quasi-static reactivity balance provides a useful way to codify the inherent response of a reactor to unprotected accident initiators. This approach has been used to illuminate the underlying physics of passive reactivity shutdown in liquid-metal-cooled fast reactors (LMRs) and has facilitated the design effort to configure LMR reactor cores for favorable inherent safety features. The purpose of this paper is to extend the quasi-static reactivity balance methodology to thermal reactor types - and in particular to the modular high-temperature gas-cooled reactor (MHTGR) where, as in LMRs, passive reactivity shutdown is a design goal

  3. A CFD-based wind solver for a fast response transport and dispersion model

    Gowardhan, Akshay A [Los Alamos National Laboratory; Brown, Michael J [Los Alamos National Laboratory; Pardyjak, Eric R [UNIV OF UTAH; Senocak, Inanc [BOISE STATE UNIV

    2010-01-01

    In many cities, ambient air quality is deteriorating leading to concerns about the health of city inhabitants. In urban areas with narrow streets surrounded by clusters of tall buildings, called street canyons, air pollution from traffic emissions and other sources is difficult to disperse and may accumulate resulting in high pollutant concentrations. For various situations, including the evacuation of populated areas in the event of an accidental or deliberate release of chemical, biological and radiological agents, it is important that models should be developed that produce urban flow fields quickly. For these reasons it has become important to predict the flow field in urban street canyons. Various computational techniques have been used to calculate these flow fields, but these techniques are often computationally intensive. Most fast response models currently in use are at a disadvantage in these cases as they are unable to correlate highly heterogeneous urban structures with the diagnostic parameterizations on which they are based. In this paper, a fast and reasonably accurate computational fluid dynamics (CFD) technique that solves the Navier-Stokes equations for complex urban areas has been developed called QUIC-CFD (Q-CFD). This technique represents an intermediate balance between fast (on the order of minutes for a several block problem) and reasonably accurate solutions. The paper details the solution procedure and validates this model for various simple and complex urban geometries.

  4. Target Localization by Resolving the Time Synchronization Problem in Bistatic Radar Systems Using Space Fast-Time Adaptive Processor

    D. Madurasinghe

    2009-01-01

    Full Text Available The proposed technique allows the radar receiver to accurately estimate the range of a large number of targets using a transmitter of opportunity as long as the location of the transmitter is known. The technique does not depend on the use of communication satellites or GPS systems, instead it relies on the availability of the direct transmit copy of the signal from the transmitter and the reflected paths off the various targets. An array-based space-fast time adaptive processor is implemented in order to estimate the path difference between the direct signal and the delayed signal, which bounces off the target. This procedure allows us to estimate the target distance as well as bearing.

  5. Response time patterns in a stated choice experiment

    Börjesson, Maria; Fosgerau, Mogens

    2015-01-01

    This paper studies how response times vary between unlabelled binary choice occasions in a stated choice (SC) experiment, with alternatives differing with respect to in-vehicle travel time and travel cost. The pattern of response times is interpreted as an indicator of the cognitive processes...... employed by the respondents when making their choices. We find clear signs of reference-dependence in response times in the form of a strong gain–loss asymmetry. Moreover, different patterns of response times for travel time and travel cost indicate that these attributes are processed in different ways by...

  6. Transcriptomic and metabolomic profiling of chicken adipose tissue in response to insulin neutralization and fasting

    Ji Bo

    2012-08-01

    Full Text Available Abstract Background Domestic broiler chickens rapidly accumulate adipose tissue due to intensive genetic selection for rapid growth and are naturally hyperglycemic and insulin resistant, making them an attractive addition to the suite of rodent models used for studies of obesity and type 2 diabetes in humans. Furthermore, chicken adipose tissue is considered as poorly sensitive to insulin and lipolysis is under glucagon control. Excessive fat accumulation is also an economic and environmental concern for the broiler industry due to the loss of feed efficiency and excessive nitrogen wasting, as well as a negative trait for consumers who are increasingly conscious of dietary fat intake. Understanding the control of avian adipose tissue metabolism would both enhance the utility of chicken as a model organism for human obesity and insulin resistance and highlight new approaches to reduce fat deposition in commercial chickens. Results We combined transcriptomics and metabolomics to characterize the response of chicken adipose tissue to two energy manipulations, fasting and insulin deprivation in the fed state. Sixteen to 17 day-old commercial broiler chickens (ISA915 were fed ad libitum, fasted for five hours, or fed but deprived of insulin by injections of anti-insulin serum. Pair-wise contrasts of expression data identified a total of 2016 genes that were differentially expressed after correction for multiple testing, with the vast majority of differences due to fasting (1780 genes. Gene Ontology and KEGG pathway analyses indicated that a short term fast impacted expression of genes in a broad selection of pathways related to metabolism, signaling and adipogenesis. The effects of insulin neutralization largely overlapped with the response to fasting, but with more modest effects on adipose tissue metabolism. Tissue metabolomics indicated unique effects of insulin on amino acid metabolism. Conclusions Collectively, these data provide a foundation

  7. A laser diode based system for calibration of fast time-of-flight detectors

    Bertoni, R.; Bonesini, M.; de Bari, A.; Rossella, M.

    2016-05-01

    A system based on commercially available items, such as a laser diode, emitting in the visible range ~ 400 nm, and multimode fiber patches, fused fiber splitters and optical switches may be assembled, for time calibration of multi-channels time-of-flight (TOF) detectors with photomultipliers' (PMTs') readout. As available laser diode sources have unfortunately limited peak power, the main experimental problem is the tight light power budget of such a system. In addition, while the technology for fused fiber splitters is common in the Telecom wavelength range (λ ~ 850, 1300–1500 nm), it is not easily available in the visible one. Therefore, extensive laboratory tests had to be done on purpose, to qualify the used optical components, and a full scale timing calibration prototype was built. Obtained results show that with such a system, a calibration resolution (σ) in the range 20–30 ps may be within reach. Therefore, fast multi-channels TOF detectors, with timing resolutions in the range 50–100 ps, may be easily calibrated in time. Results on tested optical components may be of interest also for time calibration of different light detection systems based on PMTs, as the ones used for detection of the vacuum ultraviolet scintillation light emitted by ionizing particles in large LAr TPCs.

  8. Response modalities and time-sharing performance

    Vidulich, Michael A.

    1986-01-01

    An experiment performed to investigate the role of resource competition and asymmetric transfer in dual-task performance is described. It is shown that there is an advantage to mixed manual/speech response modality configurations that cannot be accounted for by asymmetric transfer. The present results support the multiple resources approach to the application of speech technology. Once speech recognition achieves an acceptable level of operational reliability, speech controls can be used to reduce resource competition and improve performance in multitask environments.

  9. Latent Factor Models and Analyses for Operator Response Times

    Gaver, Donald Paul; O'Muircheartaigh, I. G.

    1990-01-01

    Two models are presented for the response times of different operators to different tasks where response is initiated by one or more cues provided by the system. One model for the log-response times is a mixed or latent factor model with unequal case fixed effects and variances. The other model for the log-response times is a non-Gaussian log-extreme-value model. Procedures for estimating the parameters by maximum likelihood are presented. The models are used to analyze response time data fro...

  10. Using response times for item selection in adaptive testing

    Linden, van der Wim J.

    2008-01-01

    Response times on items can be used to improve item selection in adaptive testing provided that a probabilistic model for their distribution is available. In this research, the author used a hierarchical modeling framework with separate first-level models for the responses and response times and a s

  11. Signal and Noise Analysis in TRION -Time-Resolved Integrative Optical Fast Neutron Detector

    Vartsky, D; Mor, I; Goldberg, M B; Bar, D; Dangendorf, V

    2009-01-01

    TRION is a sub-mm spatial resolution fast neutron imaging detector, which employs an integrative optical time-of-flight technique. The detector was developed for fast neutron resonance radiography, a method capable of detecting a broad range of conventional and improvised explosives. In this study we have analyzed in detail, using Monte-Carlo calculations and experimentally determined parameters, all the processes that influence the signal and noise in the TRION detector. In contrast to event-counting detectors where the signal-to-noise ratio is dependent only on the number of detected events (quantum noise), in an energy-integrating detector additional factors, such as the fluctuations in imparted energy, number of photoelectrons, system gain and other factors will contribute to the noise. The excess noise factor (over the quantum noise) due to these processes was 4.3, 2.7, 2.1, 1.9 and 1.9 for incident neutron energies of 2, 4, 7.5, 10 and 14 MeV, respectively. It is shown that, even under ideal light colle...

  12. Time-resolved fast-neutron pinhole camera for studying thermonuclear plasmas

    Bauer, R.W.; Weingart, R.C.

    1976-02-02

    A fast-neutron pinhole camera with high detection efficiency and nanosecond time-resolution has been developed and applied to the investigation of the spatial and temporal distributions of DD- and DT-neutrons produced by thermonuclear plasmas. The pinhole consists of a specially designed 1.15 m long copper collimator with an effective aperture of 1 mm diameter. Several different types of spatial resolution detectors have been used at the image plane: (1) a multi-element, scintillation-photomultiplier system used for time-resolved measurements consisting of sixty-one individual detectors, (2) a scintillation-fiber-chamber coupled to a gated image-intensifier tube used for direct photographing of the neutron image, and (3) a propane bubble chamber used for time-integrated recording with a capability to distinguish DD- from DT-neutrons. Pulsed neutron sources with typical dimensions of 1 cm emitting of the order of 10/sup 12/ neutrons over a time period of 10-100 nsec have been investigated. A spatial resolution of 1 mm and a time resolution of approximately 10 nsec was achieved in the investigations of dense plasma compression phenomena.

  13. A fast density-based clustering algorithm for real-time Internet of Things stream.

    Amini, Amineh; Saboohi, Hadi; Wah, Teh Ying; Herawan, Tutut

    2014-01-01

    Data streams are continuously generated over time from Internet of Things (IoT) devices. The faster all of this data is analyzed, its hidden trends and patterns discovered, and new strategies created, the faster action can be taken, creating greater value for organizations. Density-based method is a prominent class in clustering data streams. It has the ability to detect arbitrary shape clusters, to handle outlier, and it does not need the number of clusters in advance. Therefore, density-based clustering algorithm is a proper choice for clustering IoT streams. Recently, several density-based algorithms have been proposed for clustering data streams. However, density-based clustering in limited time is still a challenging issue. In this paper, we propose a density-based clustering algorithm for IoT streams. The method has fast processing time to be applicable in real-time application of IoT devices. Experimental results show that the proposed approach obtains high quality results with low computation time on real and synthetic datasets. PMID:25110753

  14. A Fast Density-Based Clustering Algorithm for Real-Time Internet of Things Stream

    Amineh Amini

    2014-01-01

    Full Text Available Data streams are continuously generated over time from Internet of Things (IoT devices. The faster all of this data is analyzed, its hidden trends and patterns discovered, and new strategies created, the faster action can be taken, creating greater value for organizations. Density-based method is a prominent class in clustering data streams. It has the ability to detect arbitrary shape clusters, to handle outlier, and it does not need the number of clusters in advance. Therefore, density-based clustering algorithm is a proper choice for clustering IoT streams. Recently, several density-based algorithms have been proposed for clustering data streams. However, density-based clustering in limited time is still a challenging issue. In this paper, we propose a density-based clustering algorithm for IoT streams. The method has fast processing time to be applicable in real-time application of IoT devices. Experimental results show that the proposed approach obtains high quality results with low computation time on real and synthetic datasets.

  15. Observations of plasma response to RMP using fast movable magnetic probe on TEXTOR

    Plasma response to resonant magnetic perturbation fields (RMPs) is important for understanding the physical mechanism of instability control using RMP fields in the next generation of fusion devices, i.e. ITER. Such an investigation has been carried out in TEXTOR under different dynamic ergodic divertor (DED) configurations. The perturbed magnetic field is measured by the Fast Movable Magnetic Probe (FMMP) installed at the outer equatorial plane (low-field side). Preliminary results show that the perturbed plasma edge magnetic topology is different from the case simulated with a vacuum assumption. Plasma response to RMP depends strongly on both the location of the resonant rational flux surface and the frequency difference between the drift of the rational surface in the plasma and the external perturbation.

  16. Response time in online stated choice experiments

    Campbell, Danny; Mørkbak, Morten Raun; Olsen, Søren Bøye

    2016-01-01

    In this paper, we use paradata relating to the length of time respondents required in a self-administered online stated preference surveys. Although this issue has been previously explored, there is little guidance on how to identify and deal with ‘fast’ and ‘slow’ respondents. In this paper, we ...

  17. A novel 4D fast track finding system using precise space and time information of the hit

    Neri, Nicola; Petruzzo, Marco

    2015-01-01

    We propose a novel fast track finding system capable of reconstructing four dimensional particle trajectories in real time using precise space and time information of the hits. Recent developments in silicon pixel detectors achieved 150 ps time resolution and intense R&D is in progress to improve the timing performance, aiming at 10 ps. The use of the precise space and time information allows the suppression of background hits not compatible with the time of passage of the particle and the de...

  18. Program for the analysis of time series. [by means of fast Fourier transform algorithm

    Brown, T. J.; Brown, C. G.; Hardin, J. C.

    1974-01-01

    A digital computer program for the Fourier analysis of discrete time data is described. The program was designed to handle multiple channels of digitized data on general purpose computer systems. It is written, primarily, in a version of FORTRAN 2 currently in use on CDC 6000 series computers. Some small portions are written in CDC COMPASS, an assembler level code. However, functional descriptions of these portions are provided so that the program may be adapted for use on any facility possessing a FORTRAN compiler and random-access capability. Properly formatted digital data are windowed and analyzed by means of a fast Fourier transform algorithm to generate the following functions: (1) auto and/or cross power spectra, (2) autocorrelations and/or cross correlations, (3) Fourier coefficients, (4) coherence functions, (5) transfer functions, and (6) histograms.

  19. Detecting Fast Time Variations in the Supernova Neutrino Flux with Hyper-Kamiokande

    Migenda, Jost

    2016-01-01

    For detection of neutrinos from galactic supernovae, the planned Hyper-Kamiokande detector will be the first detector that delivers both a high event rate (about one third of the IceCube rate) and event-by-event energy information. In this thesis, we use a three-dimensional computer simulation by the Garching group to find out whether this additional information can be used to improve the detection prospects of fast time variations in the neutrino flux. We find that the amplitude of SASI oscillations of the neutrino number flux is energy-dependent. However, in this simulation, the larger amplitude in some energy bins is not sufficient to counteract the increased noise caused by the lower event rate. Finally, we derive a condition describing when it is advantageous to consider an energy bin instead of the total signal and show that this condition is satisfied if the oscillation of the mean neutrino energy is increased slightly.

  20. Evaluation of Fast-Time Wake Models Using Denver 2006 Field Experiment Data

    Ahmad, Nash’at N.; Pruis, Matthew J.

    2015-01-01

    The National Aeronautics and Space Administration conducted a series of wake vortex field experiments at Denver in 2003, 2005, and 2006. This paper describes the lidar wake vortex measurements and associated meteorological data collected during the 2006 deployment, and includes results of recent reprocessing of the lidar data using a new wake vortex algorithm and estimates of the atmospheric turbulence using a new algorithm to estimate eddy dissipation rate from the lidar data. The configuration and set-up of the 2006 field experiment allowed out-of-ground effect vortices to be tracked in lateral transport further than any previous campaign and thereby provides an opportunity to study long-lived wake vortices in moderate to low crosswinds. An evaluation of NASA's fast-time wake vortex transport and decay models using the dataset shows similar performance as previous studies using other field data.

  1. Physiotherapy Exercise After Fast-Track Total Hip and Knee Arthroplasty: Time for Reconsideration?

    Bandholm, Thomas; Kehlet, Henrik

    2012-01-01

    Bandholm T, Kehlet H. Physiotherapy exercise after fast-track total hip and knee arthroplasty: time for reconsideration? Major surgery, including total hip arthroplasty (THA) and total knee arthroplasty (TKA), is followed by a convalescence period, during which the loss of muscle strength and......-track methodology or enhanced recovery programs. It is the nature of this methodology to systematically and scientifically optimize all perioperative care components, with the overall goal of enhancing recovery. This is also the case for the care component "physiotherapy exercise" after THA and TKA. The 2 latest...... meta-analyses on the effectiveness of physiotherapy exercise after THA and TKA generally conclude that physiotherapy exercise after THA and TKA either does not work or is not very effective. The reason for this may be that the "pill" of physiotherapy exercise typically offered after THA and TKA does...

  2. A UV LED-based fast-pulsed photoelectron source for time-of-flight studies

    Valerius, K; Arlinghaus, H; Bonn, J; Hannen, V M; Hein, H; Ostrick, B; Streubel, S; Weinheimer, Ch; Zboril, M

    2009-01-01

    We report on spectroscopy and time-of-flight measurements using an 18 keV fast-pulsed photoelectron source of adjustable intensity, ranging from single photoelectrons per pulse to 5 photoelectrons per microsecond at pulse repetition rates of up to 10 kHz. Short pulses between 40 ns and 40 microseconds in length were produced by switching light emitting diodes with central output wavelengths of 265 nm and 257 nm, in the deep ultraviolet (or UV-C) regime, at kHz frequencies. Such photoelectron sources can be useful calibration devices for testing the properties of high-resolution electrostatic spectrometers, like the ones used in current neutrino mass searches.

  3. System-level Specifications of the Timing and Fast Control system for the LHCb Upgrade

    Alessio, Federico

    2014-01-01

    The LHCb experiment has proposed an upgrade towards a full 40 MHz readout system in order to run between five and ten times the initial design luminosity. The various sub-systems in the readout architecture will need to be upgraded in order to cope with higher sub-detector occupancies, higher rate and higher network load. In this paper, we describe the specifications of the new Timing and Fast Control (S- TFC) system. We define the requirements for the new S-TFC, and specify its architecture and the individual components. The system is based on a single new Readout Supervisor (S-ODIN) instantiating several S-TFC masters to allow partitioning. The communication with the readout electronics is ensured by a shared high-speed optical link network for both the distribution of timing and synchronous control information, as well as trigger/throttle communication. An interface board (SOL40) with fan-out capabilities for timing and synchronous information and fan-in capabilities for throttle and rate regulation of the...

  4. A laser diode based system for calibration of fast time-of-flight detectors

    Bonesini, M; deBari, A; Rossella, M

    2016-01-01

    A system based on commercially available items, such as a laser diode, emitting in the visible range $\\sim 400$ nm,and multimode fiber patches, fused fiber splitters and optical switches may be assembled,for time calibration of multi-channels time-of-flight (TOF) detectors with photomultipliers' (PMTs') readout. As available laser diode sources have unfortunately limited peak power, the main experimental problem is the tight light power budget of such a system. In addition, while the technology for fused fiber splitters is common in the Telecom wavelength range ($\\lambda \\sim 850, 1300-1500$ nm), it is not easily available in the visible one. Therefore, extensive laboratory tests had to be done on purpose, to qualify the used optical components, and a full scale timing calibration prototype was built. Obtained results show that with such a system, a calibration resolution ($\\sigma$) in the range 20-30 ps may be within reach. Therefore, fast multi-channels TOF detectors, with timing resolutions in the range 50...

  5. Improvement in the gamma-ray timing measurements using a fast digital oscilloscope

    The time resolutions of a new positron lifetime spectrometer based on a fast digital oscilloscope are measured using BaF2 and plastic (BC-422) scintillators. It is found that the plastic scintillator has only a small advantage in the time resolution compared to BaF2. For the cascade decay of 60Co (1.17 and 1.33 MeV), the time resolution for a pair of BC-422 plastic scintillators having a size of 40 mm in diameter and 20 mm thick is about 120 ps FWHM. This value is very close to that of BaF2. Although a time resolution of 90 ps FWHM is obtained using a pair of small BC-422 plastic scintillators (30 mm in diameter, 10 mm thick), the counting rate is nearly two orders of magnitude lower than that with BaF2. It is thus concluded that the BaF2 is the best scintillator at present for the practical positron lifetime spectroscopy

  6. The Importance of Responsibility in Times of Crisis

    Jacob Dahl Rendtorff

    2014-06-01

    Full Text Available In this paper I would like to show the importance of the concept of responsibility as the foundation of ethics in times of crisis in particular in the fields of politics and economics in the modern civilisation marked by globalization and technological progres. I consider the concept of responsibility as the key notion in order to understand the ethical duty in a modern technological civilisation. We can indeed observe a moralization of the concept of responsibility going beyond a strict legal definition in terms of imputability. The paper begins by discussing the humanistic foundations of such a concept of responsibility. It treats the historical origins of responsibility and it relates this concept to the concept of accountability. On the basis of this historical determination of the concept I would like to present the definition of the concept of responsibility as fundamental ethical principle that has increasing importance as the foundation of the principles of governance in modern welfare states. In this context the paper discusses the extension of the concept of responsibility towards institutional or corporate responsibility where responsibility does not only concerns the responsibility of individuals but also deals with the responsibility of institutional collectivities. In this way the paper is based on the following structure : 1 The ethical foundation of the concept of responsibility 2 Responsibility in technological civilisation 3 Political responsibility for good governance in the welfare state 4 Social responsibility of business corporations in times of globalization 5 Conclusion and discussion : changed conditions of responsibility in modern times.

  7. Time dependent start-up thermal analysis of a Super Fast Reactor

    Highlights: • Time dependent startup thermal analysis of a Super Fast Reactor is performed. • A recirculation system is used for pressurization and for generating supercritical steam. • MCST satisfies the criterion both during subcritical pressure and during power-raising. • MCST is not sensitive to the change of inlet temperature, gap volume and flow rate because of high flow to power ratio. • CHF is not limiting the MCST during subcritical pressure due to large margin of heat flux. -- Abstract: The startup system of a supercritical pressure light water cooled fast reactor (Super FR) is studied by time dependent thermal-hydraulic analysis. The plant analysis code is developed based on an innovative upward flow pattern in all the assemblies of the Super FR. A recirculation system consisting of a steam drum, a circulation pump, and a heat exchanger is used for the startup. Detailed procedures are performed and the maximum cladding surface temperature (MCST) at rated power, 640 °C, is used as the criterion. Firstly a small constant nuclear power is used for rising the core feed water temperature to be 280 °C through the recirculation system. Secondly, pressurization is done in the recirculation system from atmospheric to operating pressure, 25 MPa, by raising the power. Thirdly, line-switching from recirculation mode to once-through direct-cycle is performed while turbines are started by supercritical steam at supercritical pressure. Finally the power is raised to be 100% of power followed by raising the flow rate. During pressurization the heat flux margin is large due to low power used for pressurization and the MCST is much lower than the criterion. The MCST is not sensitive to the inlet temperature, the flow rate, and the gap volume of the core because of high flow to power ratio. Smaller dimension of steam drum can be used for pressurization stably. The MCST satisfies the criterion both during subcritical pressure and during power-raising

  8. Artificial diamonds as radiation-hard detectors for ultra-fast fission-fragment timing

    In the framework of the construction of the double time-of-flight spectrometer VERDI, where we aim at measuring pre- and post-neutron masses directly and simultaneously, ultra-fast time pick-up detectors based on artificial diamond material were investigated for the first time with fission fragments from 252Cf (0.5MeV/u9 fission-fragments/cm2 together with more than 3.5×109 neutrons/cm2 and 3×1010α-particles/cm2. This fluence is characteristic for fission experiments. The pre-requisite for the observed signal stability is the application of priming of the diamond material with a strong β-source for about 48 h. The intrinsic timing resolution of a 100μm thick polycrystalline CVD diamond detector with a size of 1×1 cm2 was determined to σint=(283±41)ps by comparison with Monte-Carlo simulations. Using broadband pre-amplifiers, 4-fold segmented detectors of same total size and with a thickness of 180μm show an intrinsic timing resolution of σint=(106±21)ps. This is highly competitive with the best micro-channel plate detectors. Due to the limited and batch-dependent charge collection efficiency of poly-crystalline diamond material, the detection efficiency for fission fragments may be smaller than 100%. -- Highlights: ► First use of chemical vapor deposited diamond for heavy ions with kinetic energies below 2 MeV per nucleon. ► Fission-fragment time-of-flight measurements with a timing resolution better than 150 ps. ► Radiation-hard fission event trigger to be used in an intense neutron field

  9. Sucralose Promotes Food Intake through NPY and a Neuronal Fasting Response.

    Wang, Qiao-Ping; Lin, Yong Qi; Zhang, Lei; Wilson, Yana A; Oyston, Lisa J; Cotterell, James; Qi, Yue; Khuong, Thang M; Bakhshi, Noman; Planchenault, Yoann; Browman, Duncan T; Lau, Man Tat; Cole, Tiffany A; Wong, Adam C N; Simpson, Stephen J; Cole, Adam R; Penninger, Josef M; Herzog, Herbert; Neely, G Gregory

    2016-07-12

    Non-nutritive sweeteners like sucralose are consumed by billions of people. While animal and human studies have demonstrated a link between synthetic sweetener consumption and metabolic dysregulation, the mechanisms responsible remain unknown. Here we use a diet supplemented with sucralose to investigate the long-term effects of sweet/energy imbalance. In flies, chronic sweet/energy imbalance promoted hyperactivity, insomnia, glucose intolerance, enhanced sweet taste perception, and a sustained increase in food and calories consumed, effects that are reversed upon sucralose removal. Mechanistically, this response was mapped to the ancient insulin, catecholamine, and NPF/NPY systems and the energy sensor AMPK, which together comprise a novel neuronal starvation response pathway. Interestingly, chronic sweet/energy imbalance promoted increased food intake in mammals as well, and this also occurs through an NPY-dependent mechanism. Together, our data show that chronic consumption of a sweet/energy imbalanced diet triggers a conserved neuronal fasting response and increases the motivation to eat. PMID:27411010

  10. A real-time fast radio burst: polarization detection and multiwavelength follow-up

    Petroff, E; Barr, E D; Barsdell, B R; Bhat, N D R; Bian, F; Burke-Spolaor, S; Caleb, M; Champion, D; Chandra, P; Da Costa, G; Delvaux, C; Flynn, C; Gehrels, N; Greiner, J; Jameson, A; Johnston, S; Kasliwal, M M; Keane, E F; Keller, S; Kocz, J; Kramer, M; Leloudas, G; Malesani, D; Mulchaey, J S; Ng, C; Ofek, E O; Perley, D A; Possenti, A; Schmidt, B P; Shen, Yue; Stappers, B; Tisserand, P; van Straten, W; Wolf, C

    2014-01-01

    Fast radio bursts (FRBs) are one of the most tantalizing mysteries of the radio sky; their progenitors and origins remain unknown and until now no rapid multiwavelength follow-up of an FRB has been possible. New instrumentation has decreased the time between observation and discovery from years to seconds, and enables polarimetry to be performed on FRBs for the first time. We have discovered an FRB (FRB 140514) in real-time on 14 May, 2014 at 17:14:11.06 UTC at the Parkes radio telescope and triggered follow-up at other wavelengths within hours of the event. FRB 140514 was found with a dispersion measure (DM) of 562.7(6) cm$^{-3}$ pc, giving an upper limit on source redshift of $z \\lesssim 0.5$. FRB 140514 was found to be 21$\\pm$7% (3-$\\sigma$) circularly polarized on the leading edge with a 1-$\\sigma$ upper limit on linear polarization $<10%$. We conclude that this polarization is intrinsic to the FRB. If there was any intrinsic linear polarization, as might be expected from coherent emission, then it may...

  11. Multi-purpose fast neutron spectrum analyzer with real-time signal processing

    Sulyaev, Yu.S., E-mail: sulyaev@inp.nsk.su [Budker Institute of Nuclear Physics SB RAS, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 630090 Novosibirsk (Russian Federation); Puryga, E.A.; Khilchenko, A.D. [Budker Institute of Nuclear Physics SB RAS, 630090 Novosibirsk (Russian Federation); Novosibirsk State Technical University, 630092 Novosibirsk (Russian Federation); Kvashnin, A.N. [Budker Institute of Nuclear Physics SB RAS, 630090 Novosibirsk (Russian Federation); Polosatkin, S.V. [Budker Institute of Nuclear Physics SB RAS, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 630090 Novosibirsk (Russian Federation); Rovenskikh, A.F. [Budker Institute of Nuclear Physics SB RAS, 630090 Novosibirsk (Russian Federation); Burdakov, A.V.; Grishnyaev, E.V. [Budker Institute of Nuclear Physics SB RAS, 630090 Novosibirsk (Russian Federation); Novosibirsk State Technical University, 630092 Novosibirsk (Russian Federation)

    2013-08-21

    Diagnostics of hot ion component of plasma on the products of fusion reactions is widely used on thermonuclear facilities. In case of employment of neutron spectrometers, based on organics scintillators, there is advanced technique developed to eliminate neutron pulses from gamma background—digital pulse shape discrimination. For every DPSD application it is necessary to use the fast (2–5 ns) and precise (12 bit) transient ADC unit with large amount of onboard memory for storing every digitized scintillation pulses during shot time. At present time the duration of hot thermonuclear plasma burning in large tokamaks approximate to 1 min, and this requires very high onboard memory capacity (∼100 GB). This paper describes a neutron spectrum analyzer with real-time DPSD algorithm, implemented to ADC unit. This approach saves about two orders of onboard memory capacity, gives the possibility of instant use of outcome to feedback systems. This analyzer was tested and calibrated with help of {sup 60}Co and {sup 252}Cf radiation sources, and deuterium neutron generator.

  12. Study on risk-informed determination method of allowed outage time in fast reactor systems

    The present report describes a study aiming at proposing a method to determine the allowed outage time (AOT) after detecting a failure in the equipment that stands by during fast reactor power operation by taking into account risk information rationally. In the present study, an improved risk estimation model based on the previous study was constructed so as to consider properly that the repaired component was returned to the standby state again when the repair action completed within the range of AOT. Based on the improved model, core damage probability (CDP) per each detection of the failure is expressed as a function depending on the elapsed time after failure detection. In addition, there are the upper and lower bound values of CDP, and the CDP changes monotonously (i.e., either decreases or increases) between a pair of both the bound values. If a target value of CDP that is not lower than the lower bound can be given, it is possible to determine AOT, where the point-estimation value of CDP becomes lower than or equal to the target value because CDP depends on the elapsed time. Finally, we developed the procedure for determining the AOT from the view point of maintaining the total core damage frequency less than or equal to a prescribed target value. (author)

  13. Size-selective sorting in bubble streaming flows: Particle migration on fast time scales

    Thameem, Raqeeb; Rallabandi, Bhargav; Hilgenfeldt, Sascha

    2015-11-01

    Steady streaming from ultrasonically driven microbubbles is an increasingly popular technique in microfluidics because such devices are easily manufactured and generate powerful and highly controllable flows. Combining streaming and Poiseuille transport flows allows for passive size-sensitive sorting at particle sizes and selectivities much smaller than the bubble radius. The crucial particle deflection and separation takes place over very small times (milliseconds) and length scales (20-30 microns) and can be rationalized using a simplified geometric mechanism. A quantitative theoretical description is achieved through the application of recent results on three-dimensional streaming flow field contributions. To develop a more fundamental understanding of the particle dynamics, we use high-speed photography of trajectories in polydisperse particle suspensions, recording the particle motion on the time scale of the bubble oscillation. Our data reveal the dependence of particle displacement on driving phase, particle size, oscillatory flow speed, and streaming speed. With this information, the effective repulsive force exerted by the bubble on the particle can be quantified, showing for the first time how fast, selective particle migration is effected in a streaming flow. We acknowledge support by the National Science Foundation under grant number CBET-1236141.

  14. Modeling fast stimulus-response association learning along the occipito-parieto-frontal pathway following rule instructions.

    Bugmann, Guido

    2012-01-24

    On the basis of instructions, humans are able to set up associations between sensory and motor areas of the brain separated by several neuronal relays, within a few seconds. This paper proposes a model of fast learning along the dorsal pathway, from primary visual areas to pre-motor cortex. A new synaptic learning rule is proposed where synaptic efficacies converge rapidly toward a specific value determined by the number of active inputs of a neuron, respecting a principle of resource limitation in terms of total synaptic input efficacy available to a neuron. The efficacies are stable with regards to repeated arrival of spikes in a spike train. This rule reproduces the inverse relationship between initial and final synaptic efficacy observed in long-term potentiation (LTP) experiments. Simulations of learning experiments are conducted in a multilayer network of leaky integrate-and-fire (LIF) spiking neuron models. It is proposed that cortical feedback connections convey a top-down learning-enabling signal that guides bottom-up learning in "hidden" neurons that are not directly exposed to input or output activity. Simulations of repeated presentation of the same stimulus-response pair, show that, under conditions of fast learning with probabilistic synaptic transmission, the networks tend to recruit a new sub-network at each presentation to represent the association, rather than re-using a previously trained one. This increasing allocation of neural resources results in progressively shorter execution times, in line with experimentally observed reduction in response time with practice. This article is part of a Special Issue entitled: Neural Coding. PMID:22041227

  15. Changes in energy metabolism in response to 48 h of overfeeding and fasting in Caucasians and Pima Indians

    Weyer, C; Vozarova, B; Ravussin, E; Tataranni, P A; de Courten, Barbora

    2001-01-01

    Differences in the metabolic response to overfeeding and starvation may confer susceptibility or resistance to obesity in humans. To further examine this hypothesis, we assessed the changes in 24 h energy metabolism in response to short-term overfeeding and fasting in Caucasians (C) and Pima...

  16. Fast response methods in the radiation chemistry of lethal damage in intact cells

    The radiation-induced lethal damage in bacteria and mammalian cells involves some important chemical processes which extend up to about 10-2s after the initiating energy deposition. The gas explosion technique, analogous to the use of flash photolysis in photochemistry and pulse radiolysis in radiation chemistry, was applied to examine the kinetics of some of the fast processes within intact cells. The time resolution of this technique is about 100 μs. Five nanosecond electron pulses and the rapid transition from virtually anoxic (2) to well oxygenated (>105 ppm O2) conditions can be used as the fast probes to determine the time scale of the radiosensitization by oxygen. The apparent differences between the observed intracellular kinetics of the reactions of O2 and of TAN (triacetoneamine-N-oxyl) with target damage and the reactions of these agents with DNA radicals support the view that O2 is not sensitized by reacting directly with DNA damage. In general, the processes described in this review appear to conform to simple bimolecular reaction kinetics. The intracellular reaction rates of the various agents tested are all slower than those expected from the rates of their reactions with radicals in dilute aqueous solution probably due to the complex structure of the cells. (Yamashita, S.)

  17. Timing is Everything: The Role of Time and the Business Cycle in Fast-Food Purchasing Behavior in the United States

    Hamrick, Karen; Okrent, Abigail

    2014-01-01

    Meals, snacks, and beverages purchased at fast-food restaurants have become a large and growing portion of a typical American’s budget, and have been blamed for American’s expanding waistlines and poor diet quality. Previous studies have attributed this increase to many factors including budget and time constraints, demographic and health characteristics and market-level forces but no study has been able to rigorously address the effects of all of these variables on the demand for fast foods....

  18. The usefulness of time-dependent reactor accident consequence modelling for emergency response planning

    After major releases of radionuclides into the atmosphere fast reaction of authorities will be necessary to inform the public of potential consequences and to consider and optimize mitigating actions. These activities require availability of well designed computer models, adequate and fast measurements and prior training of responsible persons. The quantitative assessment models should be capable of taking into account of actual atmospheric dispersion conditions, actual deposition situation (dry, rain, snow, fog), seasonal status of the agriculture, food processing and distribution pathways, etc. In this paper the usefulness of such models will be discussed, their limitations, the relative importance of exposure pathways and a selection of important methods to decrease the activity in food products after an accident. Real-time reactor accident consequence models should be considered as a condition sine qua non for responsible use of nuclear power for electricity production

  19. Identification of Human Adenovirus in Respiratory Samples with Luminex Respiratory Virus Panel Fast V2 Assay and Real-Time Polymerase Chain Reaction.

    Esposito, Susanna; Scala, Alessia; Bianchini, Sonia; Zampiero, Alberto; Fossali, Emilio; Principi, Nicola

    2016-01-01

    In order to compare the last version of the Respiratory Virus Panel (RVP) Fast assay for human Adenovirus (hAdv) detection with a specific real-time polymerase chain reaction (qPCR), which is considered the gold standard for hAdv detection, nasopharyngeal samples collected from 309 children (age range, four months to eight years) with respiratory tract infection were tested using the RVP Fast v2 assay (Luminex Molecular Diagnostics, Inc., Toronto, ON, Canada) and a specific TaqMan qPCR to identify hAdv DNA. The RVP Fast v2 assay detected 30/61 (49.2%) hAdv infections that had been identified by real-time qPCR, demonstrating a significantly lower detection rate (p < 0.001). The sensitivity of the RVP Fast v2 assay in comparison to qPCR was lower in younger children (42.9% vs. 57.7%; Cohen's kappa coefficient, 0.53); in samples with co-infections (40.0% vs. 56.7%; Cohen's kappa coefficient, 0.52); and in samples with hAdv type C (45.9% vs. 57.1%; Cohen's kappa coefficient, 0.60). Samples with lower viral loads were associated with a significantly lower sensitivity of the RVP Fast v2 assay (35.1% vs. 68.2%, p = 0.01; Cohen's kappa coefficients, 0.49). The RVP Fast v2 assay has important limitations for the detection of hAdv and cannot be used to evaluate whether hAdvs are the main etiologic agent responsible for an outbreak or when epidemiological studies are performed. PMID:26927078

  20. Current commutation from a fast-response circuit breaker to shunting conductor

    Reasons of failures of fast response circuit breakers (FRCB) at multistage commutation of current in the circuit with an inductive storage ring are considered, when the current commutation in the shunting conductor (SC) is not completed. The commutation mode has been determined by five dimensional parameters: commutation current, stray inductance of the circuit, rate of voltage growth across the FRCB, initial resistance of SC and characteristic power contribution. The existence of two critical current densities is stated: the first one is related to the rate of voltage growth on the FRCB and the second one is associated with the ultimate maximum voltage developed by FRCB. The obtained calculation estimations permit to determine the current density upper boundary in SC above which the commutation is impossible

  1. Heart rate response during sleep in elderly patients after fast-track hip and knee arthroplasty

    Krenk, Lene; Sørensen, Gertrud Laura; Kehlet, Henrik; Jennum, Poul

    2015-01-01

    postoperative period after fast-track hip and knee arthroplasty. Determination of autonomic function was gained from polysomnographic evaluation of 10 patients >60 years undergoing either hip or knee arthroplasty (mean age 69.9 years) evaluating HRR during the different sleep phases. Sleep monitoring took place...... major arthroplasty surgery in elderly patients may reflect a functional change in sympathetic nervous system potentially relevant for postoperative sleep changes, fatigue and cognitive function.......Variability in heart rate response (HRR) can be used as a measure for autonomic nervous system function, which may influence sleep disturbances and the recovery phase after major surgery. The aim of this study was to evaluate autonomic function by assessment of HRR during sleep arousals in the...

  2. Computationally Efficient Partial Crosstalk Cancellation in Fast Time-Varying DSL Crosstalk Environments

    Forouzan Amir R

    2007-01-01

    Full Text Available Line selection (LS, tone selection (TS, and joint tone-line selection (JTLS partial crosstalk cancellers have been proposed to reduce the online computational complexity of far-end crosstalk (FEXT cancellers in digital subscriber lines (DSL. However, when the crosstalk profile changes rapidly over time, there is an additional requirement that the partial crosstalk cancellers, particularly the LS and JTLS schemes, should also provide a low preprocessing complexity. This is in contrast to the case for perfect crosstalk cancellers. In this paper, we propose two novel channel matrix inversion methods, the approximate inverse (AI and reduced inverse (RI schemes, which reduce the recurrent complexity of the LS and JTLS schemes. Moreover, we propose two new classes of JTLS algorithms, the subsort and Lagrange JTLS algorithms, with significantly lower computational complexity than the recently proposed optimal greedy JTLS scheme. The computational complexity analysis of our algorithms shows that they provide much lower recurrent complexities than the greedy JTLS algorithm, allowing them to work efficiently in very fast time-varying crosstalk environments. Moreover, the analytical and simulation results demonstrate that our techniques are close to the optimal solution from the crosstalk cancellation point of view. The results also reveal that partial crosstalk cancellation is more beneficial in upstream DSL, particularly for short loops.

  3. Hierarchical Diffusion Models for Two-Choice Response Times

    Vandekerckhove, Joachim; Tuerlinckx, Francis; Lee, Michael D.

    2011-01-01

    Two-choice response times are a common type of data, and much research has been devoted to the development of process models for such data. However, the practical application of these models is notoriously complicated, and flexible methods are largely nonexistent. We combine a popular model for choice response times--the Wiener diffusion…

  4. CHARACTERISTICS OF A FAST RISE TIME POWER SUPPLY FOR A PULSED PLASMA REACTOR FOR CHEMICAL VAPOR DESTRUCTION

    Rotating spark gap devices for switching high-voltage direct current (dc) into a corona plasma reactor can achieve pulse rise times in the range of tens of nanoseconds. The fast rise times lead to vigorous plasma generation without sparking at instantaneous applied voltages highe...

  5. High-Voltage Power Supply With Fast Rise and Fall Times

    Bearden, Douglas B.; Acker, Richard M.; Kapuslka, Robert E.

    2007-01-01

    A special-purpose high-voltage power supply can be electronically switched on and off with fast rise and fall times, respectively. The output potential is programmable from 20 to 1,250 V. An output current of 50 A can be sustained at 1,250 V. The power supply was designed specifically for electronically shuttering a microchannel plate in an x-ray detector that must operate with exposure times as short as 1 ms. The basic design of the power supply is also adaptable to other applications in which there are requirements for rapid slewing of high voltages. The power-supply circuitry (see figure) includes a preregulator, which is used to program the output at 1/30 of the desired output potential. After the desired voltage has been set, the outputs of a pulse width modulator (PWM) are enabled and used to amplify the preregulator output potential by 30. The amplification is achieved by use of two voltage doublers with a transformer that has two primary and two secondary windings. A resistor is used to limit the current by controlling the drive voltage of two field-effect transistors (FETs) during turn-on of the PWM. A pulse transformer is used to turn on four FETs to short-circuit four output capacitors when the outputs of the PWM have been disabled. The most notable aspects of the performance of the power supply are a rise time of only 80 s and a fall time of only 60 s at a load current of 50 A or less. Another notable aspect is that the application of a 0-to-5-V square wave to a shutdown pin of the PWM causes the production of a 0-to-1,250-V square wave at the output terminals.

  6. First measurements of the kinetic response of the muse-4 fast Ads mock-up to fast neutron pulse

    The MUSE-4 experiment has started its first commissioning measurements at the beginning of the year 2001 at CEA/Cadarache (France). This international experiment co-ordinated by CEA, included in the 5FWP of the European Union and GEDEON, is intended to study the physics of fast sub-critical assemblies coupled with a pulsed external source. To achieve this objective, the GENEPI accelerator, a (d,d) or (d,t) neutron source developed at CRNS/IN2P3/ISN (Grenoble), has been coupled with the MASURCA reactor, a uranium-plutonium MOX-based fast reactor, with solid sodium simulating a liquid metal coolant and a lead buffer to simulate a spallation target. The very short neutron pulse (1 μs) provided by GENEPI, together with the possibility to change the pulse repetition rate up to 5 kHz and the different levels of sub-criticality available will facilitate a study of the reactor kinetic parameters in situations close to most of the proposed accelerator-driven Systems (ADS). The paper presents the first experimental results for dynamic measurements performed in MUSE-4 configurations. Several pulsed neutron source experiments have been carried out using the (d,d) GENEPI neutron source in configurations going from USD 1,33 to USD 12,6. In addition, noise techniques (Rossi and Feynman-alpha) have been applied to stationary states in the same range of sub-criticalities. Reactivity levels obtained by these techniques have been compared with more classic rod drop/source multiplication measurements. The kinetic parameters, β(which ranges between 330 and 360 pcm) and β/Λ (with a value of approximately 6270 s-1), have been determined by Monte Carlo and/or deterministic codes. (author)

  7. Fast Frequency Response Capability of Photovoltaic Power Plants: The Necessity of New Grid Requirements and Definitions

    Claudia Rahmann

    2014-09-01

    Full Text Available In recent years, only a small number of publications have been presented addressing power system stability with the increased use of large-scale photovoltaic (PV generation around the world. The focus of these publications was on classical stability problems, such as transient and small signal stability, without considering frequency stability. Nevertheless, with increased PV generation, its effects on system frequency response during contingencies can no longer be ignored, especially in the case of weakly interconnected networks or isolated power systems. This paper addresses the impacts of large scale PV generation on the frequency stability of power systems. The positive effects of deloaded PV power plants (PV-PPs able to support system frequency recovery during the initial seconds after major contingencies are also examined. Because this type of frequency support is not covered by current definitions, a new terminology is proposed that includes the frequency response of inertia-less generation units immediately after major power imbalances. We refer to this type of frequency support as fast frequency response (FFR. Finally, a discussion is also presented regarding the applicability and pertinence of frequency-related grid requirements for PV-PPs in the case of real power systems. The investigation is based on the isolated power system of northern Chile. The obtained results indicate that in the case of major power imbalances, no significant effects arise on the system frequency response until PV penetration levels exceed approximately 20%. From a system security perspective, the problems arise for PV penetration levels of approximately 50%, in which case, the frequency response capability in PV-PPs would be justified during certain hours of the year.

  8. A fast-response production-inventory model for deteriorating seasonal products with learning in set-ups

    Ibraheem Abdul

    2011-10-01

    Full Text Available The classical production-inventory model assumes that both demand and set-up costs are constant. However, in real manufacturing environment, managers usually embark on continuous improvement programmes that often lead to more effective use of tools and machineries and consequently reduction in set-up costs. In fact, constant emphasis on reduction of set-up costs is usually cited as one of the factors responsible for the efficiency of Japanese manufacturing methods. On the other hand, the demand for seasonal product is often characterized by a mixture of time-dependent patterns over the entire season. This paper investigates the effect of learning-based reduction in set-up costs on the optimal schedules and costs of a production-inventory system for deteriorating seasonal products. The demand pattern is a general three-phase ramp-type demand function that represents the various phases of demand commonly observed in many seasonal products in the market. A two-parameter Weibull-distribution function is used for the deterioration of items in order to make the model more generalized and realistic. The study further presents two different multi-period production strategies that can ensure a fast-response to customers’ demand and compare them with the usual single period strategy. The Numerical example and sensitivity analysis shows that learning-based reduction in set-up costs leads to higher production frequency and shorter production runs which are vital aspects of the just-in-time (JIT philosophy.

  9. A FAST AND EFFICIENT VISION BASED APPROACH FOR DETECTION OF FIRE IN REAL TIME SCENARIO

    Battise Priyanka Y.; Prof. B. S. Agarkar

    2015-01-01

    F ire is a huge serious disruption which leads to economic and environmental losses . So it is necessary to detect occurrence of fire at early stage . Alarm is not issued unless particles reach the senso rs to activate them and requires large response time. Also, infrared and ultraviolet sensors which are commonly used produce many false alarms. With the help of computer vision techniques, it is possib...

  10. Performance of a fast response miniature Adiabatic Demagnetisation Refrigerator using a single crystal tungsten magnetoresistive heat switch

    Bartlett, J.; Hardy, G.; Hepburn, I. D.

    2015-12-01

    The performance of a fast thermal response miniature Adiabatic Demagnetisation Refrigerator (ADR) is presented. The miniature ADR is comprised of a fast thermal response Chromium Potassium Alum (CPA) salt pill, two superconducting magnets and unconventionally, a single crystal tungsten magnetoresistive (MR) heat switch. The development of this ADR is a result of the ongoing development of a continuously operating millikelvin cryocooler (mKCC), which will use only magnetoresistive heat switches. The design and performance of the MR heat switch developed for the mKCC and used in the miniature ADR is presented in this paper; the heat switch has a measured Residual Resistivity Ratio of 32,000 ± 3000 and an estimated switching ratio (on thermal conductivity divided by the off thermal conductivity) of 15,200 at 3.6 K and 38,800 at 0.2 K when using a 3 T magnetic field. The performance of the miniature ADR operating from a 3.6 K bath is presented, demonstrating that a complete cycle (magnetisation, cooling to the bath and demagnetisation) can be accomplished in 82 s. A magnet current step test, conducted when the ADR is cold and fully demagnetised, has shown the thermal response of the ADR to be sub-second. The measured hold times of the ADR with just parasitic heat load are given, ranging from 3 min at 0.2 K with 13.14 μW of parasitics, to 924 min at 3 K with 4.55 μW of parasitics. The cooling power has been measured for operating temperatures in the range 0.25-3 K by applying an additional heat load to the ADR via a heater, in order to reduce the hold time to 3 min (i.e. approximately double the recycle time); the maximum cooling power of the miniature ADR (in addition to parasitic load) when operating at 250 mK is 20 μW, which increases to 45 μW at 300 mK and continues to increase linearly to nearly 1.1 mW at 3 K. To conclude, the predicted performance of a tandem continuous ADR utilising two of the miniature ADRs is presented.

  11. Fast Helical Tomotherapy in a head and neck cancer planning study: is time priceless?

    The last few years, in radiotherapy there has been a growing focus on speed of treatment delivery (largely driven by economical and commercial interests). This study investigates the influence of treatment time on plan quality for helical tomotherapy (HT), using delivery times with Volumetric Modulated Arc Therapy (VMAT; Rapid Arc [RA]) as reference. In a previous study, double arc RA (Eclipse) and standard HT plans (TomoHD™) were created for five oropharyngeal cancer patients and reported according to ICRU 83 guidelines. By modifying the beam width from 2.5 to 5.0 cm, elevating the pitch and lowering the modulation factor, “TomoFast” (TF) plans were generated with treatment times equal to RA plans. To quantify the impact of TF’s craniocaudal gradient, similar plans were generated on TomoEdgeTM (TomoEdgeFast;TEF). The homogeneity index (HI), conformity index (CI), mean dose, Dnear-max (D2) and Dnear-min (D98) of the PTVs were analyzed as well as the mean dose, specific critical doses and volumes of 26 organs at risk (OARs). Data were analyzed using repeated measures ANOVA. With a mean treatment time of 3.05 min (RA), 2.89 min (TF) and 2.95 min (TEF), PTVtherapeutic coverage was more homogeneous with TF (HI.07;SE.01) and TEF (HI.08;SE.01) compared to RA (HI.10;SE.01), while PTVprophylactic was most homogeneous with RA. Mean doses to parotid glands were comparable for RA, TF, TEF: 25.62, 25.34, 23.09 Gy for contralateral and 32.02, 31.96, 30.01 Gy for ipsilateral glands, respectively. OARs’ mean doses varied between different approaches not favoring a particular technique. TF’s higher dose to OARs at the cranial-caudal edges of the PTVs and its higher integral dose, both due to the extended cranial-caudal gradient, seems to be solved by the new TomoEdge™ software. However, all these faster techniques lose part of standard TomoHD’s OAR sparing capacity It is possible to treat oropharyngeal cancer patients using HT (TF/TEF) within time-frames observed

  12. Model for Predicting End User Web Page Response Time

    Nagarajan, Sathya Narayanan

    2012-01-01

    Perceived responsiveness of a web page is one of the most important and least understood metrics of web page design, and is critical for attracting and maintaining a large audience. Web pages can be designed to meet performance SLAs early in the product lifecycle if there is a way to predict the apparent responsiveness of a particular page layout. Response time of a web page is largely influenced by page layout and various network characteristics. Since the network characteristics vary widely from country to country, accurately modeling and predicting the perceived responsiveness of a web page from the end user's perspective has traditionally proven very difficult. We propose a model for predicting end user web page response time based on web page, network, browser download and browser rendering characteristics. We start by understanding the key parameters that affect perceived response time. We then model each of these parameters individually using experimental tests and statistical techniques. Finally, we d...

  13. Computer Response Time Measurements of Mood, Fatigue and Symptom Scale Items: Implications for Scale Response Time Uses.

    Ryman, David H.; And Others

    1988-01-01

    Describes study conducted with U.S. Marine Corps enlisted personnel to measure response time to computer-administered questionnaire items, and to evaluate how measurement of response time might be useful in various research areas. Topics addressed include mood states; the occurrence of straight lining; and experimental effects of sleep loss and…

  14. Proposal for a fast, zero suppressing circuit for the digitization of analog pulses over long memory times

    This report describes the design principles of a fast (100 MHz) time and pulse height digitizer that can record up to 15 analog pulses over 10-80 μs memory times. Unlike other triggered circuits prepulse samples are recorded without the help of an analog delay line. The low power requirements of the circuit as well as its fast read-out characteristics make it very attractive for detectors with many digitizing channels. Conventional circuits are described as a reference for the evaluation of this new design. An ECL 10 K implementation of the circuit is presented in the third section. (orig.)

  15. Reduced γ-γ time walk to below 50 ps using the multiplexed-start and multiplexed-stop fast-timing technique with LaBr3(Ce) detectors

    Régis, J.-M.; Saed-Samii, N.; Rudigier, M.; Ansari, S.; Dannhoff, M.; Esmaylzadeh, A.; Fransen, C.; Gerst, R.-B.; Jolie, J.; Karayonchev, V.; Müller-Gatermann, C.; Stegemann, S.

    2016-07-01

    The electronic γ-γ fast-timing technique using arrays consisting of many LaBr3(Ce) detectors is a powerful method to determine lifetimes of nuclear excited states with a lower limit of about 5 ps. This method requires the determination of the energy-dependent time walk of the zero time which is represented by the centroid of a prompt γ-γ time distribution. The full-energy peak versus full-energy peak prompt response difference which represents the linearly combined mean γ-γ time walk of a fast-timing array consisting of 8 LaBr3(Ce) detectors was measured using a standard 152Eu γ-ray source for the energy region of 40-1408 keV. The data were acquired using a "multiplexed-start and multiplexed-stop" analogue electronics circuitry and analysed by employing the generalized centroid difference method. Concerning the cylindrical 1.5 in.×1.5 in. LaBr3(Ce) crystals which are coupled to the Hamamatsu R9779 photomultiplier tubes, the best fast-timing array time resolution of 202(3) ps is obtained for the two prompt γ lines of 60Co by using the leading-edge timing principle. When using the zero-crossover timing principle the time resolution is degraded by up to 30%, dependent on the energy and the shaping delay time of the constant fraction discriminator model Ortec 935. The smallest γ-γ time walk to below 50 ps is obtained by using a shaping delay time of about 17 ns and an optimum "time-walk adjustment" needed for detector output pulses with amplitudes smaller than 400 mV.

  16. Fast Maximum-Likelihood Decoder for Quasi-Orthogonal Space-Time Block Code

    Adel Ahmadi

    2015-01-01

    Full Text Available Motivated by the decompositions of sphere and QR-based methods, in this paper we present an extremely fast maximum-likelihood (ML detection approach for quasi-orthogonal space-time block code (QOSTBC. The proposed algorithm with a relatively simple design exploits structure of quadrature amplitude modulation (QAM constellations to achieve its goal and can be extended to any arbitrary constellation. Our decoder utilizes a new decomposition technique for ML metric which divides the metric into independent positive parts and a positive interference part. Search spaces of symbols are substantially reduced by employing the independent parts and statistics of noise. Symbols within the search spaces are successively evaluated until the metric is minimized. Simulation results confirm that the proposed decoder’s performance is superior to many of the recently published state-of-the-art solutions in terms of complexity level. More specifically, it was possible to verify that application of the new algorithms with 1024-QAM would decrease the computational complexity compared to state-of-the-art solution with 16-QAM.

  17. Overview of the SPS/LEP fast broadcast message timing system

    A fast broadcast message system, also referred to as the general machine timing system, has recently been installed at CERN's Super Proton Synchrotron (SPS). It is used to control the SPS in its roles as a multi-cycling, multi-user service accelerator. The messages are centrally generated by an IBM compatible PC/AT card and broadcast to all users of the system. At the receiving end the frames are decoded and presented to the user in the form of either an interrupt to his intelligent equipment, a hardware pulse or a short message. They are used to synchronise the SPS when used as a 450 GeV fixed target machine, a 315 GeV p-pbar collider, a 100/450 GeV pulsing-coasting machine and also as an injector for the Large Electron Positron (LEP) machine. In the future it will also be used for LEP control. Implementation details and constraints are described, as are experience to date and foreseen expansions

  18. Real Time Computer for Plugging Indicator Control of Prototype Fast Breeder Reactor

    Prototype Fast Breeder Reactor (PFBR) is in the advanced stage of construction at Kalpakkam, India. Liquid sodium is used as coolant to transfer the heat produced in the reactor core to steam water circuit. Impurities present in the sodium are removed using purification circuit. Plugging indicator is a device used to measure the purity of the sodium. Versa Module Europa bus based Real Time Computer (RTC) system is used for plugging indicator control. Hot standby architecture consisting of dual redundant RTC system with switch over logic system is the configuration adopted to achieve fault tolerance. Plugging indicator can be controlled in two modes namely continuous and discontinuous mode. Software based Proportional-Integral-Derivative (PID) algorithms are developed for plugging indicator control wherein the set point changes dynamically for every scan interval of the RTC system. Set points and PID constants are kept as configurable in runtime in order to control the process in very efficient manner, which calls for reliable communication between RTC system and control station, hence TCP/IP protocol is adopted. Performance of the RTC system for plugging indicator control was thoroughly studied in the laboratory by simulating the inputs and monitored the control outputs. The control outputs were also monitored for different PID constants. Continuous and discontinuous mode plots were generated. (authors)

  19. Fast segmentation of stained nuclei in terabyte-scale, time resolved 3D microscopy image stacks.

    Johannes Stegmaier

    Full Text Available Automated analysis of multi-dimensional microscopy images has become an integral part of modern research in life science. Most available algorithms that provide sufficient segmentation quality, however, are infeasible for a large amount of data due to their high complexity. In this contribution we present a fast parallelized segmentation method that is especially suited for the extraction of stained nuclei from microscopy images, e.g., of developing zebrafish embryos. The idea is to transform the input image based on gradient and normal directions in the proximity of detected seed points such that it can be handled by straightforward global thresholding like Otsu's method. We evaluate the quality of the obtained segmentation results on a set of real and simulated benchmark images in 2D and 3D and show the algorithm's superior performance compared to other state-of-the-art algorithms. We achieve an up to ten-fold decrease in processing times, allowing us to process large data sets while still providing reasonable segmentation results.

  20. SeaMon-HC Buoy. A specific real-time-lightweight-moored platform as a tool for fast hydrocarbon detection

    Barrera, C.; Rueda, M. J.; Moran, R.; Llerandi, C.; Llinas, O.

    2009-04-01

    The present paper-work describes the design, last development stages and the derived results from a specific buoy platform for fast hydrocarbon detection in seawater. Under the name of SeaMon-HC, (Patent No. P200302219/8) the buoy represents a very chief tool for coastal monitoring, mainly surrounding areas with a high oil-spill risk level, like harbours, off-shore fish farming, beaches and so on. Nowadays, the Macaronesian area has nine units working in real-time, under the frame of the Red ACOMAR Network. The main innovative aspect from this buoy is the detection system. It's based in polymer technology, working as a resistance, who increase its value when the pollutant on water surface is detected. The response time from the sensor is a direct function of the hydrocarbon volatility level. For hydrocarbons with high volatility levels (like petrol), the sensor needs less time (around 3 minutes) than others with less volatility such as oils. SeaMon-HC is an autonomous, modular, reusable and a very low-cost development integrated by four subsystems (SS): SS-Flotation (different materials and shapes available); SS-Sensors (hydrocarbon detector and additional sensors -up to 15-, to solve specific sensor configuration requirements); SS-Power Supply (equipped in its basic configuration with a couple of solar modules and two 12V batteries) and the SS-Communication (based on a RF or GSM/GPRS modem technology, with a selectable communication frequency). All SeaMon-HC units, as well the rest of the ODAS buoys who joint together the Red ACOMAR Network, works in real-time, sending the collected information to the control centre that manages the communications, providing data, in a useful form (as a web site), to diverse socio-economic important sectors which make an exhaustive use of the littoral in the Macaronesian region. The access to the information by the users is done through a specific GIS software application.

  1. Synthesis and characterization of thermo-sensitive poly (N-isopropylacrylamide) hydrogel with fast response rate

    QIN Aixiang; LU Mangeng; LIU Qunfeng; ZHANG Ping

    2007-01-01

    Thermo-sensitive poly (N-isopropylacrylamide)(PNIPA) hydrogel with fast response rate was prepared by polymerizing N-isopropylacrylamide (NIPA) in an aqueous hydroxyl-propyl-methyl cellulose solution.The volume phase transition temperature of PNIPA hydrogels was characterized by differential scanning calorimetry (DSC),and the surface morphology was observed by scanning electron microscopy (SEM).The swelling ratios of the hydrogels at different temperatures were measured.Furthermore,the deswelling kinetics of the hydrogels was also studied by measuring their water retention capacity.In comparison with a conventional PNIPA hydrogel prepared in water,the hydrogel synthesized in aqueous hydroxyl-propyl-methyl cellulose solution has higher swelling ratios at temperatures below the lower critical solution temperature and exhibits a much faster response rate to temperature changes.For example,the hydrogel made in aqueous hydroxyl-propyl-methyl cellulose solution lost 89% water within 1 min and about 93% water in 4 min,whereas the conventional hydrogel lost only about 66% water in 15 min from the deswelling measurement in similar conditions.

  2. Fast time-correlated multi-element photon detector and method

    Hayden, Carl C.; Chandler, David W.; Luong, A. Khai

    2007-12-18

    Photons emitted from a sample responsive to being excited by laser pulses are directed through a prism onto a photomultiplier tube having several spaced-apart anodes. The prism alters the path of each photon as a function of its wavelength so that the wavelength determines the anode to which the photon is directed. Taps of first and second delay lines that are coupled to respective alternating anodes. When an anode receives the photon, it generates a pulse that propagates through the delay line in opposite directions from its associated tap. A timer determines first and second times from the laser pulse to the pulse reaching the first and second ends of the delay line. The difference between the first and second times corresponds to the wavelength of the emitted photon and the sum of the first and second times corresponds to the emission delay of the emitted photon.

  3. Fast response electromagnetic follow-ups from low latency GW triggers

    Howell, E. J.; Chu, Q.; Rowlinson, A.; Gao, H.; Zhang, B.; Tingay, S. J.; Boër, M.; Wen, L.

    2016-05-01

    We investigate joint low-latency gravitational wave (GW) detection and prompt electromagnetic (EM) follow-up observations of coalescing binary neutron stars (BNSs). Assuming that BNS mergers are associated with short duration gamma ray bursts (SGRBs), we evaluate if rapid EM follow-ups can capture the prompt emission, early engine activity or reveal any potential by-products such as magnetars or fast radio bursts. To examine the expected performance of extreme low-latency search pipelines, we simulate a population of coalescing BNSs and use these to estimate the detectability and localisation efficiency at different times before merger. Using observational SGRB flux data corrected to the range of the advanced GW interferometric detectors, we determine what EM observations could be achieved from low-frequency radio up to high energy γ-ray. We show that while challenging, breakthrough multi-messenger science is possible through low latency pipelines.

  4. Fast response electromagnetic follow-ups from low latency GW triggers

    Howell, E J; Rowlinson, A; Gao, H; Zhang, B; Tingay, S J; Boer, M; Wen, L

    2016-01-01

    We investigate joint low-latency gravitational wave (GW) detection and prompt electromagnetic (EM) follow-up observations of coalescing binary neutron stars (BNSs). Assuming that BNS mergers are associated with short duration gamma ray bursts (SGRBs), we evaluate if rapid EM follow-ups can capture the prompt emission, early engine activity or reveal any potential by-products such as magnetars or fast radio bursts. To examine the expected performance of extreme low-latency search pipelines, we simulate a population of coalescing BNSs and use these to estimate the detectability and localisation efficiency at different times before merger. Using observational SGRB flux data corrected to the range of the advanced GW interferometric detectors, we determine what EM observations could be achieved from low-frequency radio up to high energy $\\gamma$-ray. We show that while challenging, breakthrough multi-messenger science is possible through low latency pipelines.

  5. Temporal response and real time measurements with 5GHz photocell-oscilloscope system at low light levels

    Experiments were carried out to investigate by means of picosecond mode-locked laser pulses the performance of fast vacuum photoelectric cells associated with a high sensitivity and high speed cathode-ray tube provided with a channel plate electron multiplier. With an amplitude sensitivity of 140mV/cm an overall time of response of less than 100 ps was measured

  6. Acetobacter aceti fast identification by Real Time PCR in spoiled wine samples

    Attila Kántor

    2014-11-01

    Full Text Available Wine is a beverage that made from grape berries. However, without beneficial bacteria, we would not produce good wine. But very often wines contain acetic acid bacteria, which are undesirable in winemaking process. Acetic acid bacteria as known as a vinegar bacteria are Gram-negative, aerobic, rod-shaped and ubiquitous bacteria. This study was focused on species of acetic acid bacteria, specifically Acetobacter aceti that make spoilage in wine.The aim of our study was the identification of Acetobacter aceti in spoiled red wine samples, with plate dilution method on agar plates and using sensitive Real-time PCR (qPCR method. We cultivated Acetobacter aceti on GYC agar at 30°C, 48h. The one of main objective in the present work was the test fast, sensitive and reliable technique such as quantitative Real-time PCR and detecting the presence of Acetobacter aceti in wine samples with positive Acetobacteraceti control on amplification plot and melting curve. The next objective before  qPCR analysis was DNA extraction from wine samples incubated for one week at 28°C aerobically. We used five different red wine samples for this experiment: Alibernet 2013, Blaufränkisch 2013, Cabernet Sauvignon 2013, Dunaj 2012 and Saint-Laurent 2012. Next we extracted DNA from wine samples and from pure Acetobacter aceti CCM 3620T strain purchased from Czech collection of microorganisms in Brno. Susceptibility ofAcetobacter aceti was varied in different isolates from 102 to 107 CFU.mL-1. The number of Acetobacter cells on GYC medium ranged from 4.05 to 4.83log CFU.mL-1 in differentwine samples.The higher number of Acetobacter cells (4.83 log CFU.mL-1 was found in Cabernet Sauvignon 2013 wine.

  7. Fault tolerant distributed real time computer systems for I and C of prototype fast breeder reactor

    Highlights: • Architecture of distributed real time computer system (DRTCS) used in I and C of PFBR is explained. • Fault tolerant (hot standby) architecture, fault detection and switch over are detailed. • Scaled down model was used to study functional and performance requirements of DRTCS. • Quality of service parameters for scaled down model was critically studied. - Abstract: Prototype fast breeder reactor (PFBR) is in the advanced stage of construction at Kalpakkam, India. Three-tier architecture is adopted for instrumentation and control (I and C) of PFBR wherein bottom tier consists of real time computer (RTC) systems, middle tier consists of process computers and top tier constitutes of display stations. These RTC systems are geographically distributed and networked together with process computers and display stations. Hot standby architecture comprising of dual redundant RTC systems with switch over logic system is deployed in order to achieve fault tolerance. Fault tolerant dual redundant network connectivity is provided in each RTC system and TCP/IP protocol is selected for network communication. In order to assess the performance of distributed RTC systems, scaled down model was developed with 9 representative systems and nearly 15% of I and C signals of PFBR were connected and monitored. Functional and performance testing were carried out for each RTC system and the fault tolerant characteristics were studied by creating various faults into the system and observed the performance. Various quality of service parameters like connection establishment delay, priority parameter, transit delay, throughput, residual error ratio, etc., are critically studied for the network

  8. Improved design provides faster response time in photomultiplier

    1966-01-01

    Dynamic Crossed-Field Electron Multiplying /DCFEM/ light demodulator avoids the normal response time limitations inherent in static field devices by using time varying crossed electric and static magnetic fields. This eliminates the transit time spread that affects electrons as they proceed along the secondary emission stages of the tube.

  9. Measurement of linearity and time response parameters for photomultiplier tube

    In this paper, methods of testing linearity and time response parameters of photomultiplier tube are introduced and illustrated. Two ways of measuring the maximum anode impulse current of photomultiplier tube are contrasted. Suitable scopes of these two methods are acquired under different circumstances. At the same time, the electron transit time of photomultiplier tube is obtained by means of cable delays. (authors)

  10. Thermal emittance and response time of a cesium antimonide photocathode

    Cultrera, Luca; Bazarov, Ivan; Bartnik, Adam; Dunham, Bruce; Karkare, Siddharth; Merluzzi, Richard; Nichols, Matthew

    2011-10-01

    Measurements of the intrinsic emittance and response time of a Cs3Sb photocathode are presented. The emittance is obtained with a solenoid scan technique using a high voltage dc photoemission gun. Photoemission response time is evaluated using a RF deflecting cavity synchronized to a picosecond laser pulse train. We find that Cs3Sb has both small mean transverse energy, 160 ± 10 meV at 532 nm laser wavelength, and a prompt response time (below the resolution of our measurement) making it a suitable material for high brightness electron photoinjectors.

  11. Real-Time and Real-Fast Performance of General-Purpose and Real-Time Operating Systems in Multithreaded Physical Simulation of Complex Mechanical Systems

    Carlos Garre

    2014-01-01

    Full Text Available Physical simulation is a valuable tool in many fields of engineering for the tasks of design, prototyping, and testing. General-purpose operating systems (GPOS are designed for real-fast tasks, such as offline simulation of complex physical models that should finish as soon as possible. Interfacing hardware at a given rate (as in a hardware-in-the-loop test requires instead maximizing time determinism, for which real-time operating systems (RTOS are designed. In this paper, real-fast and real-time performance of RTOS and GPOS are compared when simulating models of high complexity with large time steps. This type of applications is usually present in the automotive industry and requires a good trade-off between real-fast and real-time performance. The performance of an RTOS and a GPOS is compared by running a tire model scalable on the number of degrees-of-freedom and parallel threads. The benchmark shows that the GPOS present better performance in real-fast runs but worse in real-time due to nonexplicit task switches and to the latency associated with interprocess communication (IPC and task switch.

  12. Assessing recognition memory using confidence ratings and response times.

    Weidemann, Christoph T; Kahana, Michael J

    2016-04-01

    Classification of stimuli into categories (such as 'old' and 'new' in tests of recognition memory or 'present' versus 'absent' in signal detection tasks) requires the mapping of internal signals to discrete responses. Introspective judgements about a given choice response are regularly employed in research, legal and clinical settings in an effort to measure the signal that is thought to be the basis of the classification decision. Correlations between introspective judgements and task performance suggest that such ratings often do convey information about internal states that are relevant for a given task, but well-known limitations of introspection call the fidelity of this information into question. We investigated to what extent response times can reveal information usually assessed with explicit confidence ratings. We quantitatively compared response times to confidence ratings in their ability to qualify recognition memory decisions and found convergent results suggesting that much of the information from confidence ratings can be obtained from response times. PMID:27152209

  13. Fast Direct Injection Mass-Spectrometric Characterization of Stimuli for Insect Electrophysiology by Proton Transfer Reaction-Time of Flight Mass-Spectrometry (PTR-ToF-MS

    Franco Biasioli

    2012-03-01

    Full Text Available Electrophysiological techniques are used in insect neuroscience to measure the response of olfactory neurons to volatile odour stimuli. Widely used systems to deliver an olfactory stimulus to a test insect include airstream guided flow through glass cartridges loaded with a given volatile compound on a sorbent support. Precise measurement of the quantity of compound reaching the sensory organ of the test organism is an urgent task in insect electrophysiology. In this study we evaluated the performances of the recent realised proton transfer reaction-time of flight mass-spectrometry (PTR-ToF-MS as a fast and selective gas sensor. In particular, we characterised the gas emission from cartridges loaded with a set of volatile compounds belonging to different chemical classes and commonly used in electrophysiological experiments. PTR-ToF-MS allowed a fast monitoring of all investigated compounds with sufficient sensitivity and time resolution. The detection and the quantification of air contaminants and solvent or synthetic standards impurities allowed a precise quantification of the stimulus exiting the cartridge. The outcome of this study was twofold: on one hand we showed that PTR-ToF-MS allows monitoring fast processes with high sensitivity by real time detection of a broad number of compounds; on the other hand we provided a tool to solve an important issue in insect electrophysiology.

  14. The Importance of Responsibility in Times of Crisis

    Jacob Dahl Rendtorff

    2014-01-01

    In this paper I would like to show the importance of the concept of responsibility as the foundation of ethics in times of crisis in particular in the fields of politics and economics in the modern civilisation marked by globalization and technological progres. I consider the concept of responsibility as the key notion in order to understand the ethical duty in a modern technological civilisation. We can indeed observe a moralization of the concept of responsibility going beyond a strict lega...

  15. 45 CFR 612.5 - Timing of responses to requests.

    2010-10-01

    ... AVAILABILITY OF RECORDS AND INFORMATION § 612.5 Timing of responses to requests. (a) In general. NSF ordinarily... physical safety of an individual; or (B) An urgency to inform the public about an actual or alleged...

  16. Congestion Service Facilities Location Problem with Promise of Response Time

    Dandan Hu

    2013-01-01

    Full Text Available In many services, promise of specific response time is advertised as a commitment by the service providers for the customer satisfaction. Congestion on service facilities could delay the delivery of the services and hurts the overall satisfaction. In this paper, congestion service facilities location problem with promise of response time is studied, and a mixed integer nonlinear programming model is presented with budget constrained. The facilities are modeled as M/M/c queues. The decision variables of the model are the locations of the service facilities and the number of servers at each facility. The objective function is to maximize the demands served within specific response time promised by the service provider. To solve this problem, we propose an algorithm that combines greedy and genetic algorithms. In order to verify the proposed algorithm, a lot of computational experiments are tested. And the results demonstrate that response time has a significant impact on location decision.

  17. Time domain modeling of tunable response of graphene

    Prokopeva, Ludmila; Emani, Naresh K.; Boltasseva, Alexandra;

    2013-01-01

    We present a causal numerical model for time domain simulations of the optical response of graphene. The dielectric function is approximated with a conductivity term, a Drude term and a number of the critical points terms....

  18. Improved time response for large area microchannel plate photomultiplier tubes in fusion diagnostics

    Fusion diagnostics that utilise high speed scintillators often need to capture a large area of light with a high degree of time accuracy. Microchannel plate (MCP) photomultiplier tubes (PMTs) are recognised as the leading device for capturing fast optical signals. However, when manufactured in their traditional proximity focused construction, the time response performance is reduced as the active area increases. This is due to two main factors: the capacitance of a large anode and the difficulty of obtaining small pore MCPs with a large area. Collaboration between Photek and AWE has produced prototype devices that combine the excellent time response of small area MCP-PMTs with a large active area by replacing the traditional proximity-gap front section with an electro-optically focused photocathode to MCP. We present results from both single and double MCP devices with a 40 mm diameter active area and show simulations for the 100 mm device being built this year

  19. Improved time response for large area microchannel plate photomultiplier tubes in fusion diagnostics

    Milnes, J. S.; Horsfield, C. J.; Conneely, T. M.; Howorth, J.

    2014-11-01

    Fusion diagnostics that utilise high speed scintillators often need to capture a large area of light with a high degree of time accuracy. Microchannel plate (MCP) photomultiplier tubes (PMTs) are recognised as the leading device for capturing fast optical signals. However, when manufactured in their traditional proximity focused construction, the time response performance is reduced as the active area increases. This is due to two main factors: the capacitance of a large anode and the difficulty of obtaining small pore MCPs with a large area. Collaboration between Photek and AWE has produced prototype devices that combine the excellent time response of small area MCP-PMTs with a large active area by replacing the traditional proximity-gap front section with an electro-optically focused photocathode to MCP. We present results from both single and double MCP devices with a 40 mm diameter active area and show simulations for the 100 mm device being built this year.

  20. A Fast Topological Trigger for Real Time Analysis of Nanosecond Phenomena; Opening the Gamma Ray Window to Our Universe

    Krennrich, Frank [Iowa State University

    2013-09-24

    This work was to enable the development of a proof-of-principle nanosecond trigger system that is designed to perform a real time analysis of fast Cherenkov light flashes from air showers. The basic building blocks of the trigger system have been designed and constructed, and a real world system is now operating in the VERITAS experiment.

  1. Determinants of Children's Use of and Time Spent in Fast-Food and Full-Service Restaurants

    McIntosh, Alex; Kubena, Karen S.; Tolle, Glen; Dean, Wesley; Kim, Mi-Jeong; Jan, Jie-Sheng; Anding, Jenna

    2011-01-01

    Objective: Identify parental and children's determinants of children's use of and time spent in fast-food (FF) and full-service (FS) restaurants. Design: Analysis of cross-sectional data. Setting: Parents were interviewed by phone; children were interviewed in their homes. Participants: Parents and children ages 9-11 or 13-15 from 312 families…

  2. Intervening to Influence Fast-Food Choices: Assessing Response Generalization in Nutrition-Related Behavior

    Keene, Wesley Ryan

    2004-01-01

    A large-scale intervention, designed to increase healthier fast-food consumption, was evaluated at a national fast-food chain. Participants included fast-food consumers at three separate restaurant locations in southwestern Virginia. Each restaurant received three phases, consisting of fourteen days each. Two of the restaurants were exposed to two conditions, A (Baseline) and B (Intervention), while the other restaurant served as a control. Restaurant 1 received the following phases, wit...

  3. Time-resolved observation of fast domain-walls driven by vertical spin currents in short tracks

    Sampaio, Joao; Lequeux, Steven; Chanthbouala, Andre; Cros, Vincent; Grollier, Julie [Unité Mixte de Physique CNRS/Thales and Université Paris-Sud 11, 1 Ave. A. Fresnel, 91767 Palaiseau (France); Metaxas, Peter J. [Unité Mixte de Physique CNRS/Thales and Université Paris-Sud 11, 1 Ave. A. Fresnel, 91767 Palaiseau (France); School of Physics, M013, University of Western Australia, 35 Stirling Highway, Crawley WA 6009 (Australia); Matsumoto, Rie; Yakushiji, Kay; Kubota, Hitoshi; Fukushima, Akio; Yuasa, Shinji [National Institute of Advanced Industrial Science and Technology (AIST) 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Nishimura, Kazumasa; Nagamine, Yoshinori; Maehara, Hiroki; Tsunekawa, Koji [Process Development Center, Canon ANELVA Corporation, Kurigi 2-5-1, Asao, Kawasaki, Kanagawa 215-8550 (Japan)

    2013-12-09

    We present time-resolved measurements of the displacement of magnetic domain-walls (DWs) driven by vertical spin-polarized currents in track-shaped magnetic tunnel junctions. In these structures, we observe very high DW velocities (600 m/s) at current densities below 10{sup 7} A/cm{sup 2}. We show that the efficient spin-transfer torque combined with a short propagation distance allows avoiding the Walker breakdown process and achieving deterministic, reversible, and fast (≈1 ns) DW-mediated switching of magnetic tunnel junction elements, which is of great interest for the implementation of fast DW-based spintronic devices.

  4. Time-resolved observation of fast domain-walls driven by vertical spin currents in short tracks

    Sampaio, Joao; Lequeux, Steven; Metaxas, Peter J.; Chanthbouala, Andre; Matsumoto, Rie; Yakushiji, Kay; Kubota, Hitoshi; Fukushima, Akio; Yuasa, Shinji; Nishimura, Kazumasa; Nagamine, Yoshinori; Maehara, Hiroki; Tsunekawa, Koji; Cros, Vincent; Grollier, Julie

    2013-12-01

    We present time-resolved measurements of the displacement of magnetic domain-walls (DWs) driven by vertical spin-polarized currents in track-shaped magnetic tunnel junctions. In these structures, we observe very high DW velocities (600 m/s) at current densities below 107 A/cm2. We show that the efficient spin-transfer torque combined with a short propagation distance allows avoiding the Walker breakdown process and achieving deterministic, reversible, and fast (≈1 ns) DW-mediated switching of magnetic tunnel junction elements, which is of great interest for the implementation of fast DW-based spintronic devices.

  5. Femtosecond response time measurements of a Cs2Te photocathode

    Aryshev, A; Honda, Y; Terunuma, N; Urakawa, J

    2015-01-01

    We present the response time measurements of a Cs2Te photocathode illuminated with two 100 fs duration, variable time separation laser pulses at 266 nm wavelength. The response time was confirmed in dispersive region downstream of a 12-cell standing wave S-band acceleration structure using a well-known RF zero-crossing technique. At the same time it was also measured by changing mechanical path-length difference between two micro-bunches. Both methods agree that Cs2Te photocathode time response is of the order of 250 fs and thereby it is possible to generate and control a THz sequence of relativistic electron bunches by a conventional S-band RF gun. This result further opens a possibility to construct wide-range tunable THz FEL.

  6. Fast response air-to-fuel ratio measurements using a novel device based on a wide band lambda sensor

    A crucial parameter influencing the formation of pollutant gases in internal combustion engines is the air-to-fuel ratio (AFR). During transients on gasoline and diesel engines, significant AFR excursions from target values can occur, but cycle-by-cycle AFR resolution, which is helpful in understanding the origin of deviations, is difficult to achieve with existing hardware. This is because current electrochemical devices such as universal exhaust gas oxygen (UEGO) sensors have a time constant of 50–100 ms, depending on the engine running conditions. This paper describes the development of a fast reacting device based on a wide band lambda sensor which has a maximum time constant of ∼20 ms and enables cyclic AFR measurements for engine speeds of up to ∼4000 rpm. The design incorporates a controlled sensor environment which results in insensitivity to sample temperature and pressure. In order to guide the development process, a computational model was developed to predict the effect of pressure and temperature on the diffusion mechanism. Investigations regarding the sensor output and response were carried out, and sensitivities to temperature and pressure are examined. Finally, engine measurements are presented

  7. Time response of temperature sensors using neural networks

    Primary coolant RTDs (Resistance Temperature Detector) typically feed the plant's control and safety systems and must, therefore, be very accurate and have good dynamic performance. The response time of RTDs has been characterized by a single parameter called the time constant defined as the time it takes for the sensor output to achieve 63.2 percent of its final value after a step change in temperature. This step change is typically achieved by suddenly immersing the sensor in a rotating tank of water, called Plunge Test. In nuclear reactors, however, plunge testing is inconvenient because nuclear reactor service conditions are difficult to reproduce in the laboratory. An in-situ test method called LCSR - Loop Current Step Response test was developed to measure remotely the response time of RTDs. In the LCSR method, the response time of the sensor is identified by means of the LCSR transformation that involves the dynamic response modal time constants determination using a nodal heat-transfer model. For this reason, this calculation is not simple and requires specialized personnel. This work combines the two methodologies, Plunge test and LCSR test, using neural networks. With the use of neural networks it will not be necessary to use the LCSR transformation to determine sensor's time constant and this leads to more robust results. (author)

  8. Fast-response fiber-optic anemometer with temperature self-compensation.

    Liu, Guigen; Hou, Weilin; Qiao, Wei; Han, Ming

    2015-05-18

    We report a novel fiber-optic anemometer with self-temperature compensation capability based on a Fabry-Pérot interferometer (FPI) formed by a thin silicon film attached to the end face of a single-mode fiber. Guided in the fiber are a visible laser beam from a 635 nm diode laser used to heat the FPI and a white-light in the infrared wavelength range as the signal light to interrogate the optical length of the FPI. Cooling effects on the heated sensor head by wind is converted to a wavelength blueshift of the reflection spectral fringes of the FPI. Self-temperature-compensated measurement of wind speed is achieved by recording the difference in fringe wavelengths when the heating laser is turned on and then off. Large thermal-optic coefficient and thermal expansion coefficient of silicon render a high sensitivity that can also be easily tuned by altering the heating laser power. Furthermore, the large thermal diffusivity and the small mass of the thin silicon film endow a fast sensor response. PMID:26074604

  9. A "package solution" fast track program can reduce the diagnostic waiting time in head and neck cancer

    Sørensen, Jesper Roed; Johansen, Jørgen; Gano, Lars;

    2014-01-01

    In 2007, a fast track program for patients with suspicion of head and neck cancer (HNC) was introduced in Denmark to reduce unnecessary waiting time. The program was based on so called "package solutions" including pre-booked slots for outpatient evaluation, imaging, and diagnostic surgical...... procedures. The purpose of this study is to present a model for fast track handling of patients suspicious of cancer in the head and neck region and to evaluate the effect of implementation on the diagnostic work up time. Patients with suspicion of HNC referred to the same university department of ENT Head...... and Neck Surgery during three comparable time intervals 2006-2007, 2007-2008, and 2011-2012 (groups 1-3) were investigated. We recorded the time from patient referral, to first consultation and final diagnosis. The first interval was before initiation of the "package solution", the second just after...

  10. Time response of temperature sensors using neural networks

    In a PWR nuclear power plant, the primary coolant temperature and feedwater temperature are measured using RTDs (Resistance Temperature Detectors). These RTDs typically feed the plant's control and safety systems and must, therefore, be very accurate and have good dynamic performance. The response time of RTDs is characterized by a single parameter called the Plunge Time Constant defined as the time it takes the sensor output to achieve 63.2 percent of its final value after a step change in temperature. Nuclear reactor service conditions are difficult to reproduce in the laboratory, and an in-situ test method called LCSR (Loop Current Step Response) test was developed to measure remotely the response time of RTDs. >From this test, the time constant of the sensor is identified by means of the LCSR transformation that involves the dynamic response modal time constants determination using a nodal heat-transfer model. This calculation is not simple and requires specialized personnel. For this reason an Artificial Neural Network has been developed to predict the time constant of RTD from LCSR test transient. It eliminates the transformations involved in the LCSR application. A series of LCSR tests on RTDs generates the response transients of the sensors, the input data of the networks. Plunge tests are used to determine the time constants of the RTDs, the desired output of the ANN, trained using these sets of input/output data. This methodology was firstly applied to theoretical data simulating 10 RTDs with different time constant values, resulting in an average error of about 0.74 %. Experimental data from three different RTDs was used to predict time constant resulting in a maximum error of 3,34 %. The time constants values predicted from ANN were compared with those obtained from traditional way resulting in an average error of about 18 % and that shows the network is able to predict accurately the sensor time constant. (author)

  11. Ultra-fast consensus of discrete-time multi-agent systems with multi-step predictive output feedback

    Zhang, Wenle; Liu, Jianchang

    2016-04-01

    This article addresses the ultra-fast consensus problem of high-order discrete-time multi-agent systems based on a unified consensus framework. A novel multi-step predictive output mechanism is proposed under a directed communication topology containing a spanning tree. By predicting the outputs of a network several steps ahead and adding this information into the consensus protocol, it is shown that the asymptotic convergence factor is improved by a power of q + 1 compared to the routine consensus. The difficult problem of selecting the optimal control gain is solved well by introducing a variable called convergence step. In addition, the ultra-fast formation achievement is studied on the basis of this new consensus protocol. Finally, the ultra-fast consensus with respect to a reference model and robust consensus is discussed. Some simulations are performed to illustrate the effectiveness of the theoretical results.

  12. Fast-response optical and near-infrared GRB science with RATIR and RIMAS

    Capone, John; RIMAS Collaboration, RATIR project Team

    2016-01-01

    As the Universe's most luminous transient events, long gamma-ray bursts (GRBs) are observed at cosmological distances. The afterglow emission generated by the burst's interaction with the surrounding medium presents the opportunity to study the local environment, as well as intervening systems. The transient nature of these events requires observations starting within minutes of the GRB to maximize the scientific opportunities.This dissertation work comprises efforts to advance the field with a new instrument, the Rapid Infrared Imager and Spectrograph (RIMAS). The optical design is complicated by the broad band coverage (0.97 to 2.39 microns) and the necessity of transmissive optics due to space and weight limitations on the telescope. Additionally, the entire optical system must be cooled to cryogenic temperatures to decrease the background from thermal emission. The completed instrument will be permanently installed on Lowell Observatory's new 4.3 meter Discovery Channel Telescope (DCT) located in Happy Jack, Arizona. The fast slew time of the telescope, combined with the instrument's ability to image in two bands simultaneously and switch to spectroscopic configurations in under a minute will allow observers to obtain photometric data within minutes and spectra within ~ ten minutes.In addition to instrumentation work on RIMAS's optics, early time photometric light curves have been studied primarily using data from the Reionization and Transients Infrared/Optical Project (RATIR). Early time photometric data in six optical and near-infrared (NIR) bands has allowed a study of color evolution in the early to late time SEDs. This study probes possible impacts of the GRB on the local medium as well as intrinsic changes in the afterglow emission.This work is made possible by the RATIR and RIMAS collaborations as well as financial support by the NSF.

  13. Disaster Response Team FAST Skills Training with a Portable Ultrasound Simulator Compared to Traditional Training: Pilot Study

    Paddock, Michael T.

    2015-03-01

    Full Text Available Introduction: Pre-hospital focused assessment with sonography in trauma (FAST has been effectively used to improve patient care in multiple mass casualty events throughout the world. Although requisite FAST knowledge may now be learned remotely by disaster response team members, traditional live instructor and model hands-on FAST skills training remains logistically challenging. The objective of this pilot study was to compare the effectiveness of a novel portable ultrasound (US simulator with traditional FAST skills training for a deployed mixed provider disaster response team. Methods: We randomized participants into one of three training groups stratified by provider role: Group A. Traditional Skills Training, Group B. US Simulator Skills Training, and Group C. Traditional Skills Training Plus US Simulator Skills Training. After skills training, we measured participants’ FAST image acquisition and interpretation skills using a standardized direct observation tool (SDOT with healthy models and review of FAST patient images. Pre- and post-course US and FAST knowledge were also assessed using a previously validated multiple-choice evaluation. We used the ANOVA procedure to determine the statistical significance of differences between the means of each group’s skills scores. Paired sample t-tests were used to determine the statistical significance of pre- and post-course mean knowledge scores within groups. Results: We enrolled 36 participants, 12 randomized to each training group. Randomization resulted in similar distribution of participants between training groups with respect to provider role, age, sex, and prior US training. For the FAST SDOT image acquisition and interpretation mean skills scores, there was no statistically significant difference between training groups. For US and FAST mean knowledge scores, there was a statistically significant improvement between pre- and post-course scores within each group, but again there was not

  14. Conceptual Question Response Times in Peer Instruction Classrooms

    Miller, Kelly; Lasry, Nathaniel; Lukoff, Brian; Schell, Julie; Mazur, Eric

    2014-01-01

    Classroom response systems are widely used in interactive teaching environments as a way to engage students by asking them questions. Previous research on the time taken by students to respond to conceptual questions has yielded insights on how students think and change conceptions. We measure the amount of time students take to respond to…

  15. A novel Fast Gas Chromatography based technique for higher time resolution measurements of speciated monoterpenes in air

    Jones, C. E.; Kato, S.; Nakashima, Y.; Kajii, Y.

    2013-12-01

    Biogenic emissions supply the largest fraction of non-methane volatile organic compounds (VOC) from the biosphere to the atmospheric boundary layer, and typically comprise a complex mixture of reactive terpenes. Due to this chemical complexity, achieving comprehensive measurements of biogenic VOC (BVOC) in air within a satisfactory time resolution is analytically challenging. To address this, we have developed a novel, fully automated Fast Gas Chromatography (Fast-GC) based technique to provide higher time resolution monitoring of monoterpenes (and selected other C9-C15 terpenes) during plant emission studies and in ambient air. To our knowledge, this is the first study to apply a Fast-GC based separation technique to achieve quantification of terpenes in air. Three chromatography methods have been developed for atmospheric terpene analysis under different sampling scenarios. Each method facilitates chromatographic separation of selected BVOC within a significantly reduced analysis time compared to conventional GC methods, whilst maintaining the ability to quantify individual monoterpene structural isomers. Using this approach, the C10-C15 BVOC composition of single plant emissions may be characterised within a ~ 14 min analysis time. Moreover, in situ quantification of 12 monoterpenes in unpolluted ambient air may be achieved within an ~ 11 min chromatographic separation time (increasing to ~ 19 min when simultaneous quantification of multiple oxygenated C9-C10 terpenoids is required, and/or when concentrations of anthropogenic VOC are significant). This corresponds to a two- to fivefold increase in measurement frequency compared to conventional GC methods. Here we outline the technical details and analytical capability of this chromatographic approach, and present the first in situ Fast-GC observations of 6 monoterpenes and the oxygenated BVOC linalool in ambient air. During this field deployment within a suburban forest ~ 30 km west of central Tokyo, Japan, the

  16. Fast Response Shape Memory Effect Titanium Nickel (TiNi) Foam Torque Tubes

    Jardine, Peter

    2014-01-01

    Shape Change Technologies has developed a process to manufacture net-shaped TiNi foam torque tubes that demonstrate the shape memory effect. The torque tubes dramatically reduce response time by a factor of 10. This Phase II project matured the actuator technology by rigorously characterizing the process to optimize the quality of the TiNi and developing a set of metrics to provide ISO 9002 quality assurance. A laboratory virtual instrument engineering workbench (LabVIEW'TM')-based, real-time control of the torsional actuators was developed. These actuators were developed with The Boeing Company for aerospace applications.

  17. A fast time-amplitude converter for low-energy physics measurements

    This converter permits the measurement of neutron times of flight up to 150 ns. The saw-tooth generator employs a 6BN6 tube fed at low voltage. There are two main points to be noted. The first relates to the tube itself: the influence of the inter-electrode capacitances increases with the speed of the signals, so that it was necessary to provide efficient neutrodyning of the No. 3 grid anode capacitance, which disturbed the conversion. The other point is that the exactness of the time definition is limited owing to the amplitude spectrum of the signals from the photomultiplier which makes it difficult to determine the instant that corresponds to a pulse. To reduce this difficulty, the authors took a selection of measurements. The performance of the equipment was checked under simulated normal working conditions: the two instants are defined by two distinct detection channels, each having a photomultiplier and a scintillator. The half-height width of a peak corresponding to a fixed delay gives the time definition; values were obtained from 0.8 to 1.3 ns for the half-height width of the peak, depending on the setting, and the drift for 15 hours of operation remained less than 0.3 % of the range. The linearity of the response curve as measured by accident coincidence is better than ± 0.3 % between 5 and 95 % of the measured area. (author)

  18. Study on proliferation time and response time for proliferation resistance evaluation

    'Proliferation time' is one of the proliferation resistance measures adopted by the Generation IV Nuclear Energy Systems International Forum (GIF) Proliferation Resistance and Physical Protection (PR and PP) evaluation methodology. A longer proliferation time would provide the international society with more time to intervene politically in order to dissuade the State from completing its nuclear weapons program. A longer proliferation time would therefore contribute to the enhancement of proliferation resistance of a given nuclear energy system. Two methods are considered for judging whether the proliferation time is long enough: 1) comparison of the proliferation times between a reference nuclear energy system and the subject system, and 2) comparison between the proliferation time and the response time, which can be defined as the time available to the international society to make a political intervention. This paper focuses on the latter method and examines how the response time can be estimated by reviewing prior incidents. (author)

  19. Response Time Optimization for Replica Selection Service in Data Grids

    Husni H.E. AL-Mistarihi

    2008-01-01

    Full Text Available Problem Statement: Data Grid architecture provides a scalable infrastructure for grid services in order to manage data files and their corresponding replicas that were distributed across the globe. The grid services are designed to support a variety of data grid applications (jobs and projects. Replica selection is a high-level service that chooses a replica location from among many distributed replicas with the minimum response time for the users' jobs. Estimating the response time accurately in the grid environment is not an easy task. The current systems expose high response time in selecting the required replicas because the response time is estimated by considering the data transfer time only. Approach: We proposed a replica selection system that selects the best replica location for the users' running jobs in a minimum response time that can be estimated by considering new factors besides the data transfer time, namely, the storage access latency and the replica requests that waiting in the storage queue. Results: The performance of the proposed system was compared with a similar system that exists in the literature namely, SimpleOptimiser. The simulation results demonstrated that our system performed better than the SimpleOptimiser on an average of 6%. Conclusions: The proposed system can select the best replica location in a lesser response time than the SimpleOptimise. The efficiency of the proposed system is 6% higher than the SimpleOptimise. The efficiency level has a high impact on the quality of service that is perceived by grid users in a data grid environment where the data files are relatively big. For example, the data files produced from the scientific applications are of the size hundreds of Terabytes.

  20. Speed-Accuracy Response Models: Scoring Rules Based on Response Time and Accuracy

    Maris, Gunter; van der Maas, Han

    2012-01-01

    Starting from an explicit scoring rule for time limit tasks incorporating both response time and accuracy, and a definite trade-off between speed and accuracy, a response model is derived. Since the scoring rule is interpreted as a sufficient statistic, the model belongs to the exponential family. The various marginal and conditional distributions…

  1. Reduced computational cost in the calculation of worst case response time for real time systems

    Urriza, José M.; Schorb, Lucas; Orozco, Javier D.; Cayssials, Ricardo

    2009-01-01

    Modern Real Time Operating Systems require reducing computational costs even though the microprocessors become more powerful each day. It is usual that Real Time Operating Systems for embedded systems have advance features to administrate the resources of the applications that they support. In order to guarantee either the schedulability of the system or the schedulability of a new task in a dynamic Real Time System, it is necessary to know the Worst Case Response Time of the Real Time tasks ...

  2. SOA Does Not Reveal the Absolute Time Course of Cognitive Processing in Fast Priming Experiments

    Tzur, Boaz; Frost, Ram

    2007-01-01

    Applying Bloch's law to visual word recognition research, both exposure duration of the prime and its luminance determine the prime's overall energy, and consequently determine the size of the priming effect. Nevertheless, experimenters using fast-priming paradigms traditionally focus only on the SOA between prime and target to reflect the…

  3. Transient electromagnetic responses during the transmitter on-time

    Schultz, Gregory M.; Miller, Jonathan S.; Song, Lin-Ping; Pasion, Leonard

    2010-04-01

    Current time-domain electromagnetic induction instruments generally only utilize data acquired after the cessation of the transmitted field. During this "off time", signals are dominated by induced eddy currents and magnetic surface modes, but do not fully capture the magnetostatic response of permeable and conductive metallic ordnance. In this paper, we investigate the response of EMI systems that measure signals during excitation of the primary magnetic field (the so-called "on-time"). Our analysis shows that on-time signals have great potential to yield useful information that is not often exploited in current EMI systems. We compare analytical models to data from state-of-the-art time-domain EM sensors that have the capability to sample receivers during the on-time. We present modeling results that represent the responses from different current ramps and on-time waveforms for objects and ground. We consider target and clutter objects and grounds having a range of material properties, shapes and sizes, and configurations and investigate signal processing and inversion methods for target detection and discrimination. Specifically, correlations between on-time and off-time signals are shown to be a powerful tool for discriminating ferrous and non-ferrous metallic objects.

  4. Low grade glioma - extent and timing of response to radiotherapy

    Purpose/Objective: While postoperative radiotherapy has been suggested to improve survival in patients with subtotally resected low grade gliomas, their rate of radiographic response and correlation of response with outcome has not been well documented. Material and Methods: Twenty adults with non-pilocytic, supratentorial low grade gliomas treated between 1988-1995 who had measurable residual tumor after surgery and complete followup imaging were analysed for radiographic response to radiotherapy. The degree and timing of response to radiation were determined by comparing tumor volumes on post-operative/pre-radiation; post-radiation and subsequent follow-up CT scans. Radiographic response to radiotherapy was correlated with clinical symptomatology and progression free survival. Results: Median postoperative/pre-radiotherapy tumor volume was 32.5 cm3. At the time of maximal response post radiotherapy, volumes were reduced to a median of 13.5 cm3 for a median volume decrease of 7.5 cm3. Tumor response was judged as complete in(3(20)) , partial in (7(20)), minor in (6(20)) and stable in (4(20)) for an overall response rate of (16(20)) (80%). Of the 16 patients responding to radiotherapy, maximal response was seen on the first follow-up scan in 15 (median time to follow-up scan was 2.8 months following initiation of radiation treatments). Only one tumor had a protracted response, continuing to decrease in size between the end of radiation treatment and approximately 18 months later. A greater proportion of those patients exhibiting a response to radiation had an improvement in clinical symptomatology ((7(16))) versus non-responders ((0(4))). There were (5(20)) patients who developed recurrent tumor at a median of 32 months post-radiation for an actuarial 5 year progression free survival of 75%. All 5 who recurred had demonstrated an initial response to radiotherapy and all recurrences were within the previously radiated field. On univariate analysis of progression

  5. FACTORS RESPONSIBLE FOR TURNOVER IN A FAST FOOD COMPANY OF SANTA MARIA – RS

    Marian dos Santos Rosa

    2012-05-01

    Full Text Available In the current scene of the organizations, each time more, the collaborator comes conquering excellent space, where the good course of the functional activities depends on the motivation of each one of these members. Inside of this context, the present objective study to analyze the organizational climate, focusing in the motivation and the rotation of the collaborators of a great company of Fast Food of the city of Saint Maria- RS, known world-wide in this sort. Study of cases was carried through, using the Survey method, being the characterized research as exploratory, quantitative and descriptive, where 57 collaborators had answered to a questionnaire of 65 questions having aimed at to answer the problematic one of the study. The gotten results disclose that the collaborators correctly are trained and as consequence the quality is seen as a positive factor, however one has left of these collaborators if it showed not motivated, influenced for the half organizational not to be very healthful, had to the environment of extreme pressure that is part of the routine of this organization, beyond a sufficiently young team of collaborators, main factors of an index of turnover considerable, identified in this company.

  6. Fast response double series resonant high-voltage DC-DC converter

    Lee, S. S.; Iqbal, S.; Kamarol, M.

    2012-10-01

    In this paper, a novel double series resonant high-voltage dc-dc converter with dual-mode pulse frequency modulation (PFM) control scheme is proposed. The proposed topology consists of two series resonant tanks and hence two resonant currents flow in each switching period. Moreover, it consists of two high-voltage transformer with the leakage inductances are absorbed as resonant inductor in the series resonant tanks. The secondary output of both transformers are rectified and mixed before supplying to load. In the resonant mode operation, the series resonant tanks are energized alternately by controlling two Insulated Gate Bipolar Transistor (IGBT) switches with pulse frequency modulation (PFM). This topology operates in discontinuous conduction mode (DCM) with all IGBT switches operating in zero current switching (ZCS) condition and hence no switching loss occurs. To achieve fast rise in output voltage, a dual-mode PFM control during start-up of the converter is proposed. In this operation, the inverter is started at a high switching frequency and as the output voltage reaches 90% of the target value, the switching frequency is reduced to a value which corresponds to the target output voltage. This can effectively reduce the rise time of the output voltage and prevent overshoot. Experimental results collected from a 100-W laboratory prototype are presented to verify the effectiveness of the proposed system.

  7. Endocrine response to realimentation in young northern elephant seals (Mirounga angustirostris): Indications for development of fasting adaptation.

    Dailey, Rachael E; Fontaine, Christine M; Avery, Julie P

    2016-09-01

    Most organisms undergo changes in their environment, both predictably and unpredictably, which require them to alter priorities in nutrient allocation with regards to food availability. Species that more predictably encounter extended periods of limited food resources or intake while mitigating the negative effects of starvation are considered to be fasting adapted. Northern elephant seals (NES) are one such species and routinely undergo extended periods of fasting for breeding, molting, as well as a post-weaning fast at 6-8weeks of age. However, during unusual times of nutritional deprivation, animals may enter stage III fasting. While fasting and foraging in this species has been extensively studied, realimentation following fasting beyond normal life history parameters has not been investigated. In this study, changes in ghrelin, growth hormone (GH), and insulin-like growth factor (IGF)-I were compared across 8weeks of realimentation following emaciation in three age classes: neonates, post-molt pups, and yearlings. Longitudinal changes in hormone profiles indicate that neonate and post-molt pups are slow to recover mass and positive energy balance despite an energy dense diet fed at 10% body mass. In addition, ghrelin and GH concentrations remained elevated in post-molt pups compared to other age classes. Changes in hormone concentrations early in realimentation indicate that yearling animals recover more rapidly from periods of nutritional deprivation than do younger animals. Overall, this suggests that the ability to regulate metabolic homeostasis with regards to nutrient allocation may develop over time, even in a species that is considered to be fasting adapted. PMID:27288636

  8. A 3 A sink/source current fast transient response low-dropout G{sub m} driven linear regulator

    Chu Xiuqin; Li Qingwei; Lai Xinquan; Yuan Bing [Institute of Electronic CAD, Xidian University, Xi' an 710071 (China); Li Yanming [School of Electronic and Control Engineering, Chang' an University, Xi' an 710064 (China); Zhao Yongrui, E-mail: liqw309@163.com, E-mail: xqchu@mail.xidian.edu.cn [Key Laboratory of High-Speed Circuit Design and EMC, Ministry of Education, Xidian University, Xi' an 710071 (China)

    2011-06-15

    A 3 A sink/source G{sub m}-driven CMOS low-dropout regulator (LDO), specially designed for low input voltage and low cost, is presented by utilizing the structure of a current mirror G{sub m} (transconductance) driving technique, which provides high stability as well as a fast load transient response. The proposed LDO was fabricated by a 0.5 {mu}m standard CMOS process, and the die size is as small as 1.0 mm{sup 2}. The proposed LDO dissipates 220 {mu}A of quiescent current in no-load conditions and is able to deliver up to 3 A of load current. The measured results show that the output voltage can be resumed within 2 {mu}s with a less than 1 mV overshoot and undershoot in the output current step from -1.8 to 1.8 A with a 0.1 {mu}s rising and falling time at three 10 {mu}F ceramic capacitors. (semiconductor integrated circuits)

  9. Study of toroidal current penetration during current ramp in JIPP T-IIU with fast response Zeeman polarimeter

    The toroidal current penetration is studied in current ramp experiments of the JIPP T-IIU tokamak. The poloidal magnetic field profile in the peripheral region of a plasma (0.5 ≤ ρ ≤ 1.0) has been measured directly with a newly developed fast response Zeeman polarimeter. The experimental results indicate that an obvious skin effect of toroidal current density is clearly observed during both the current ramp-up and ramp-down experiments. The experimentally obtained toroidal current density profiles are well described by the profiles calculated on the assumption of the neoclassical electrical conductivity. Quasi-linear Δ'-analysis of tearing modes for the measured current density profile is consistent with time behaviour of coherent MHD modes such as m=4/n=1 or m=3/n=1 (m: poloidal mode number, n: toroidal mode number) often observed during the current ramp-up phase. The effect of these MHD modes on current penetration during the current ramp-up discharges is studied. (author)

  10. The time reversal effect of the impulse response of crust

    郑文衡; 王乘; 陈湘鹏

    2001-01-01

    In this paper, the time reversal processes of impulse response of crust are simulated by means of a dynamical finite element method (DFEM). The results indicate that a small undulating load during a long period may cause a fo-cused brevity impact in a chaos-response system. The physical principle for this phenomenon is that the wave interferes or multiples superposition. Based on this knowledge, a new view toward the mechanism for preparing and triggering an earthquake is proposed. Finally, an interpretation of crust response to the sea tides is given.

  11. Reaction-time response of a large commercial aircraft

    The reaction-time response of a large commercial aircraft is defined. The aircraft is examined as a thin-walled tubular missile. The impact is assumed soft, and the target's effect on the reaction-time response is neglected. The reaction-time response is defined assuming a normal impact on a rigid wall. The reaction-time response is defined with the analytical Riera method and with the numerical explicit finite element method. The Riera force history is solved with the finite difference method. For the finite element method, two codes are used: Abaqus/Explicit and LS-DYNA. Focus is on the sensitivity study of the used methods. The outer shell of the aircraft is modeled, and an approximation for the mass-distribution is made. Sensitivity to modeling assumptions is studied in order to get information on the adequacy of modeling. The results indicate relatively small sensitivity to modeling assumptions. The wings should be modeled more accurately in order to obtain the dominant frequency response in global structural analysis. (author)

  12. Unsaturated-zone fast-path flow calculations for Yucca Mountain groundwater travel time analyses (GWTT-94)

    Arnold, B.W.; Altman, S.J. [Sandia National Labs., Albuquerque, NM (United States); Robey, T.H. [Spectra Research Institute, Albuquerque, NM (United States)] [and others

    1995-08-01

    Evaluation of groundwater travel time (GWTT) is required as part of the investigation of the suitability of Yucca Mountain as a potential high-level nuclear-waste repository site. The Nuclear Regulatory Commission`s GWTT regulation is considered to be a measure of the intrinsic ability of the site to contain radionuclide releases from the repository. The work reported here is the first step in a program to provide an estimate of GWTT at the Yucca Mountain site in support of the DOE`s Technical Site Suitability and as a component of a license application. Preliminary estimation of the GWTT distribution in the unsaturated zone was accomplished using a numerical model of the physical processes of groundwater flow in the fractured, porous medium of the bedrock. Based on prior investigations of groundwater flow at the site, fractures are thought to provide the fastest paths for groundwater flow; conditions that lead to flow in fractures were investigated and simulated. Uncertainty in the geologic interpretation of Yucca Mountain was incorporated through the use of geostatistical simulations, while variability of hydrogeologic parameters within each unit was accounted for by the random sampling of parameter probability density functions. The composite-porosity formulation of groundwater flow was employed to simulate flow in both the matrix and fracture domains. In this conceptualization, the occurrence of locally saturated conditions within the unsaturated zone is responsible for the initiation of fast-path flow through fractures. The results of the GWTT-94 study show that heterogeneity in the hydraulic properties of the model domain is an important factor in simulating local regions of high groundwater saturation. Capillary-pressure conditions at the surface boundary influence the extent of the local saturation simulated.

  13. Unsaturated-zone fast-path flow calculations for Yucca Mountain groundwater travel time analyses (GWTT-94)

    Evaluation of groundwater travel time (GWTT) is required as part of the investigation of the suitability of Yucca Mountain as a potential high-level nuclear-waste repository site. The Nuclear Regulatory Commission's GWTT regulation is considered to be a measure of the intrinsic ability of the site to contain radionuclide releases from the repository. The work reported here is the first step in a program to provide an estimate of GWTT at the Yucca Mountain site in support of the DOE's Technical Site Suitability and as a component of a license application. Preliminary estimation of the GWTT distribution in the unsaturated zone was accomplished using a numerical model of the physical processes of groundwater flow in the fractured, porous medium of the bedrock. Based on prior investigations of groundwater flow at the site, fractures are thought to provide the fastest paths for groundwater flow; conditions that lead to flow in fractures were investigated and simulated. Uncertainty in the geologic interpretation of Yucca Mountain was incorporated through the use of geostatistical simulations, while variability of hydrogeologic parameters within each unit was accounted for by the random sampling of parameter probability density functions. The composite-porosity formulation of groundwater flow was employed to simulate flow in both the matrix and fracture domains. In this conceptualization, the occurrence of locally saturated conditions within the unsaturated zone is responsible for the initiation of fast-path flow through fractures. The results of the GWTT-94 study show that heterogeneity in the hydraulic properties of the model domain is an important factor in simulating local regions of high groundwater saturation. Capillary-pressure conditions at the surface boundary influence the extent of the local saturation simulated

  14. Detectors for Time-of-Flight Fast-Neutron Radiography: 1. Neutron Counting Gas Detector

    Dangendorf, V.; Breskin, A.; Chechik, R.; Goldberg, M; Laczko, G; Mor, I.; Reginatto, M.; Vartsky, D.

    2004-01-01

    One of our two methods for fast-neutron imaging with spectrometric capability is presented here. It is a neutron-counting technique based on a hydrogenous neutron converter coupled to Gaseous Electron Multipliers (GEM). The principles of the detection techniques and the optimization of the converter, electron amplification and the readout are described. Evaluation of the properties are derived from a experiment in a pulsed neutron beam of spectral distribution between 2 and 10 MeV

  15. The first synchrotron infrared beamlines at the Advanced Light Source: spectromicroscopy and fast timing

    Martin, Michael C.; McKinney, Wayne R.

    1999-01-01

    Two recently commissioned infrared beamlines on the 1.4 bending magnet port at the Advanced Light Source, LBNL, are described. Using a synchrotron as an IR source provides three primary advantages: increased brightness, very fast light pulses, and enhanced far-IRflux. The considerable brightness advantage manifests itself most beneficially when performing spectroscopy on a microscopic length scale. Beamline (BL) 1.4.3 is a dedicated FTIR spectromicroscopy beamline, where a diffraction-l...

  16. A fast, flexible and low cost real time data acquisition system for nuclear physics experiments

    A system has been developed to permit fast, efficient data collection from a relatively complex nuclear experiment. Incorporated into this system is the communication framework for on-line analysis of the incoming data. The system makes extensive use of readily available low cost Intel based microprocessors. Results from recent measurements of the 16O(γ,n) cross section made using tagged photons, performed at previously unachievable collection rates are presented. 6 refs., 6 figs

  17. Time Trends in Fast Food Consumption and Its Association with Obesity among Children in China

    Xue, Hong; Wu, Yang; Wang, Xiaoyu; Wang, Youfa

    2016-01-01

    Objective Study the trends in Western fast food consumption (FFC) among Chinese school-age children and the association between FFC and obesity using nationwide survey data. Design Cross-sectional and longitudinal analyses were conducted to study the trends in FFC and the associations between FFC and weight status (overweight, obesity and body mass index (BMI) z-score). Setting Longitudinal data from families were collected in the 2004 and 2009 China Health and Nutrition Survey (covering nine...

  18. A GPU-based real time high performance computing service in a fast plant system controller prototype for ITER

    Nieto, J., E-mail: jnieto@sec.upm.es [Grupo de Investigacion en Instrumentacion y Acustica Aplicada. Universidad Politecnica de Madrid, Crta. Valencia Km-7, Madrid 28031 Spain (Spain); Arcas, G. de; Ruiz, M. [Grupo de Investigacion en Instrumentacion y Acustica Aplicada. Universidad Politecnica de Madrid, Crta. Valencia Km-7, Madrid 28031 Spain (Spain); Vega, J. [Asociacion EURATOM/CIEMAT para Fusion, Madrid (Spain); Lopez, J.M.; Barrera, E. [Grupo de Investigacion en Instrumentacion y Acustica Aplicada. Universidad Politecnica de Madrid, Crta. Valencia Km-7, Madrid 28031 Spain (Spain); Castro, R. [Asociacion EURATOM/CIEMAT para Fusion, Madrid (Spain); Sanz, D. [Grupo de Investigacion en Instrumentacion y Acustica Aplicada. Universidad Politecnica de Madrid, Crta. Valencia Km-7, Madrid 28031 Spain (Spain); Utzel, N.; Makijarvi, P.; Zabeo, L. [ITER Organization, CS 90 046, 13067 St. Paul lez Durance Cedex (France)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Implementation of fast plant system controller (FPSC) for ITER CODAC. Black-Right-Pointing-Pointer GPU-based real time high performance computing service. Black-Right-Pointing-Pointer Performance evaluation with respect to other solutions based in multi-core processors. - Abstract: EURATOM/CIEMAT and the Technical University of Madrid UPM are involved in the development of a FPSC (fast plant system control) prototype for ITER based on PXIe form factor. The FPSC architecture includes a GPU-based real time high performance computing service which has been integrated under EPICS (experimental physics and industrial control system). In this work we present the design of this service and its performance evaluation with respect to other solutions based in multi-core processors. Plasma pre-processing algorithms, illustrative of the type of tasks that could be required for both control and diagnostics, are used during the performance evaluation.

  19. A novel 4D fast track finding system using precise space and time information of the hit

    Neri, Nicola

    2015-01-01

    We propose a novel fast track finding system capable of reconstructing four dimensional particle trajectories in real time using precise space and time information of the hits. Recent developments in silicon pixel detectors achieved 150 ps time resolution and intense R&D is in progress to improve the timing performance, aiming at 10 ps. The use of the precise space and time information allows the suppression of background hits not compatible with the time of passage of the particle and the determination of its time evolution. The fast track finding device that we are proposing is based on a massively parallel algorithm implemented in commercial field-programmable gate array using a pipelined architecture. We describe the algorithm and its implementation for a tracking system prototype based on 8 planes of silicon sensors used as a case study. According to simulations the suppression of noise hits is effective in reducing fake track combinations and improving real-time track reconstruction in presence of b...

  20. Dynamical theory of responsivity and response time of a high temperature superconductor photo-thermoelectrical bolometer

    Dynamical theory of responsivity and response time for an high temperature superconductor (HTSC) photo-thermoelectrical bolometer is analysed in this paper. There is a thermoelectric feedback (TEF) due to the heat transfer from the sensitive area (HTSC-BiSb thermojunction) towards the cold junction of the thermocouple. This is in addition to the normal electrothermal feedback (ETF) between the detector and the substrate, in a photoelectrical bolometer. The two legs of the thermocouple are connected in a parallel geometry configuration. It is seen that TEF can be used in combination with the ETF to enhance responsivity and response time of the detector

  1. Soft real-time EPICS extensions for fast control: A case study applied to a TCV equilibrium algorithm

    Castro, R., E-mail: rodrigo.castro@visite.es [Asociación EURATOM/CIEMAT para Fusión, Madrid (Spain); Romero, J.A.; Vega, J. [Asociación EURATOM/CIEMAT para Fusión, Madrid (Spain); Nieto, J.; Ruiz, M.; Sanz, D.; Barrera, E.; De Arcas, G. [Grupo de Investigación en Instrumentación y Acústica Aplicada, UPM, Madrid (Spain)

    2014-05-15

    Highlights: • Implementation of a soft real-time control system based on EPICS technology. • High data throughput system control implementation. • GPU technology applied to fast control. • EPICS fast control based solution. • Fast control and data acquisition in Linux. - Abstract: For new control systems development, ITER distributes CODAC Core System that is a software package based on Linux RedHat, and includes EPICS (Experimental Physics and Industrial Control System) as software control system solution. EPICS technology is being widely used for implementing control systems in research experiments and it is a very well tested technology, but presents important lacks to meet fast control requirements. To manage and process massive amounts of acquired data, EPICS requires additional functions such as: data block oriented transmissions, links with speed-optimized data buffers and synchronization mechanisms not based on system interruptions. This EPICS limitation turned out clearly during the development of the Fast Plant System Controller Prototype for ITER based on PXIe platform. In this work, we present a solution that, on the one hand, is completely compatible and based on EPCIS technology, and on the other hand, extends EPICS technology for implementing high performance fast control systems with soft-real time characteristics. This development includes components such as: data acquisition, processing, monitoring, data archiving, and data streaming (via network and shared memory). Additionally, it is important to remark that this system is compatible with multiple Graphics Processing Units (GPUs) and is able to integrate MatLab code through MatLab engine connections. It preserves EPICS modularity, enabling system modification or extension with a simple change of configuration, and finally it enables parallelization based on data distribution to different processing components. With the objective of illustrating the presented solution in an actual

  2. Soft real-time EPICS extensions for fast control: A case study applied to a TCV equilibrium algorithm

    Highlights: • Implementation of a soft real-time control system based on EPICS technology. • High data throughput system control implementation. • GPU technology applied to fast control. • EPICS fast control based solution. • Fast control and data acquisition in Linux. - Abstract: For new control systems development, ITER distributes CODAC Core System that is a software package based on Linux RedHat, and includes EPICS (Experimental Physics and Industrial Control System) as software control system solution. EPICS technology is being widely used for implementing control systems in research experiments and it is a very well tested technology, but presents important lacks to meet fast control requirements. To manage and process massive amounts of acquired data, EPICS requires additional functions such as: data block oriented transmissions, links with speed-optimized data buffers and synchronization mechanisms not based on system interruptions. This EPICS limitation turned out clearly during the development of the Fast Plant System Controller Prototype for ITER based on PXIe platform. In this work, we present a solution that, on the one hand, is completely compatible and based on EPCIS technology, and on the other hand, extends EPICS technology for implementing high performance fast control systems with soft-real time characteristics. This development includes components such as: data acquisition, processing, monitoring, data archiving, and data streaming (via network and shared memory). Additionally, it is important to remark that this system is compatible with multiple Graphics Processing Units (GPUs) and is able to integrate MatLab code through MatLab engine connections. It preserves EPICS modularity, enabling system modification or extension with a simple change of configuration, and finally it enables parallelization based on data distribution to different processing components. With the objective of illustrating the presented solution in an actual

  3. Fast Beam Investigations of Two- and Three-Body Photodissociation by Time- and Position-Coincidence Imaging

    Crider, Paul

    2010-01-01

    Fast beam photofragment translational spectroscopy has been used to elucidate the photodissociation dynamics of small radicals and closed-shell anions. Imaging of photofragments in time- and position-coincidence allows the determination of mass distributions, translational energy distributions [P(ET) distributions], and in the case of three-body fragmentation channels, ternary Dalitz plots depicting the momentum disposal among the fragments. These data yield information about the potential en...

  4. Timing criteria for supplemental BWR emergency response equipment

    The Great Tohuku Earthquake and subsequent Tsunami represented a double failure event which destroyed offsite power connections to Fukushima-Daiichi site and then destroyed on-site electrical systems needed to run decay heat removal systems. The accident could have been mitigated had there been supplemental portable battery chargers, supplemental pumps, and in-place piping connections to provide alternate decay heat removal. In response to this event in the USA, two national response centers, one in Memphis, Tennessee, and another in Phoenix, Arizona, will begin operation. They will be able to dispatch supplemental emergency response equipment to any nuclear plant in the U.S. within 24 hours. In order to define requirements for supplemental nuclear power plant emergency response equipment maintained onsite vs. in a regional support center it is necessary to confirm: (a) the earliest time such equipment might be needed depending on the specific scenario, (b) the nominal time to move the equipment from a storage location either on-site or within the region of a nuclear power plant, and (c) the time required to connect in the supplemental equipment to use it. This paper describes an evaluation process for a BWR-4 with a Mark I Containment starting with: (a) severe accident simulation to define best estimate times available for recovery based on the specific scenario, (b) identify the key supplemental response equipment needed at specific times to accomplish recovery of key safety functions, and (c) evaluate what types of equipment should be warehoused on-site vs. in regional response centers. (authors)

  5. EVALUATION OF A FAST-RESPONSE URBAN WIND MODEL - COMPARISON TO SINGLE-BUILDING WIND TUNNEL DATA

    E.R. PARDYJAK; M.J. BROWN

    2001-08-01

    Prediction of the 3-dimensional flow field around buildings and other obstacles is important for a number of applications, including urban air quality studies, the tracking of plumes from accidental releases of toxic air contaminants, indoor/outdoor air pollution problems, and thermal comfort assessments. Various types of computational fluid dynamics (CFD) models have been used for determining the flow fields around buildings (e.g., Reisner et al., 1998; Eichhorn et al., 1988). Comparisons to measurements show that these models work reasonably well for the most part (e.g., Ehrhard et al., 2 ; Johnson and Hunter, 1998; Murakami, 1997). However, CFD models are computationally intensive and for some applications turn-around time is of the essence. For example, planning and assessment studies in which hundreds of cases must be analyzed or emergency response scenarios in which plume transport must be computed quickly. Several fast-response dispersion models of varying levels of fidelity have been developed to explicitly account for the effects of a single building or groups of buildings (e.g., UDM - Hall et al. (2000), NRC-Ramsdell and Fosmire (1995), CBP-3 - Yamartino and Wiegand (1986), APRAC - Daerdt et al. (1973)). Although a few of these models include the Hotchkiss and Harlow (1973) analytical solution for potential flow in a notch to describe the velocity field within an urban canyon, in general, these models do not explicitly compute the velocity field around groups of buildings. The EPA PRIME model (Schulman et al., 2000) has been empirically derived to provide streamlines around a single isolated building.

  6. EVALUATION OF A FAST-RESPONSE URBAN WIND MODEL - COMPARISON TO SINGLE-BUILDING WIND TUNNEL DATA

    Prediction of the 3-dimensional flow field around buildings and other obstacles is important for a number of applications, including urban air quality studies, the tracking of plumes from accidental releases of toxic air contaminants, indoor/outdoor air pollution problems, and thermal comfort assessments. Various types of computational fluid dynamics (CFD) models have been used for determining the flow fields around buildings (e.g., Reisner et al., 1998; Eichhorn et al., 1988). Comparisons to measurements show that these models work reasonably well for the most part (e.g., Ehrhard et al., 2 ; Johnson and Hunter, 1998; Murakami, 1997). However, CFD models are computationally intensive and for some applications turn-around time is of the essence. For example, planning and assessment studies in which hundreds of cases must be analyzed or emergency response scenarios in which plume transport must be computed quickly. Several fast-response dispersion models of varying levels of fidelity have been developed to explicitly account for the effects of a single building or groups of buildings (e.g., UDM - Hall et al. (2000), NRC-Ramsdell and Fosmire (1995), CBP-3 - Yamartino and Wiegand (1986), APRAC - Daerdt et al. (1973)). Although a few of these models include the Hotchkiss and Harlow (1973) analytical solution for potential flow in a notch to describe the velocity field within an urban canyon, in general, these models do not explicitly compute the velocity field around groups of buildings. The EPA PRIME model (Schulman et al., 2000) has been empirically derived to provide streamlines around a single isolated building

  7. Development of fast response bi-luminophore pressure-sensitive paint by means of an inkjet printing technique

    A novel fast response bi-luminophore pressure-sensitive paint (PSP) by inkjet printing of sensor-dot arrays on an anodized aluminum (AA) substrate has been developed for unsteady flow measurements. A bi-luminophore AA-PSP, which is a combination of PSP and temperature-sensitive paint (TSP), is essential for precise pressure measurements, because the PSP result needs the temperature correction. However, a conventional bi-luminophore AA-PSP prepared by a dipping method does not work well due to the interference between the PSP and TSP luminophores. To overcome this problem, we have developed isolated dot arrays of PSP and TSP formed on an anodized aluminum substrate by an inkjet printing method. In this study, platinum tetrakis (pentafluorophenyl) porphyrin (PtTFPP) and ZnS-AgInS2 (ZAIS) were employed as pressure- and temperature-sensitive dyes, respectively. A suitable solvent was chosen for each dye to form the dots with uniform, high luminescence intensity, and high sensitivity. The developed bi-luminophore AA-PSP could simultaneously measure pressure and temperature and could reduce the temperature effect of the PSP from −0.97%/K (without temperature correction) to −0.01%/K (with temperature correction). It showed a pressure response time of 17.8  ±  0.8 μs at 90% pressure rise to a step change of pressure, which is in the same range as a conventional AA-PSP. (paper)

  8. Planck 2013 results. VII. HFI time response and beams

    Ade, P A R; Armitage-Caplan, C; Arnaud, M; Ashdown, M; Atrio-Barandela, F; Aumont, J; Baccigalupi, C; Banday, A J; Barreiro, R B; Battaner, E; Benabed, K; Benoît, A; Benoit-Lévy, A; Bernard, J -P; Bersanelli, M; Bielewicz, P; Bobin, J; Bock, J J; Bond, J R; Borrill, J; Bouchet, F R; Bowyer, J W; Bridges, M; Bucher, M; Burigana, C; Cardoso, J -F; Catalano, A; Challinor, A; Chamballu, A; Chary, R -R; Chiang, L -Y; Chiang, H C; Christensen, P R; Church, S; Clements, D L; Colombi, S; Colombo, L P L; Couchot, F; Coulais, A; Crill, B P; Curto, A; Cuttaia, F; Danese, L; Davies, R D; de Bernardis, P; de Rosa, A; de Zotti, G; Delabrouille, J; Delouis, J -M; Désert, F -X; Diego, J M; Dole, H; Donzelli, S; Doré, O; Douspis, M; Dunkley, J; Dupac, X; Efstathiou, G; Enßlin, T A; Eriksen, H K; Finelli, F; Forni, O; Frailis, M; Fraisse, A A; Franceschi, E; Galeotta, S; Ganga, K; Giard, M; Giraud-Héraud, Y; González-Nuevo, J; Górski, K M; Gratton, S; Gregorio, A; Gruppuso, A; Gudmundsson, J E; Haissinski, J; Hansen, F K; Hanson, D; Harrison, D; Henrot-Versillé, S; Hernández-Monteagudo, C; Herranz, D; Hildebrandt, S R; Hivon, E; Hobson, M; Holmes, W A; Hornstrup, A; Hou, Z; Hovest, W; Huffenberger, K M; Jaffe, T R; Jaffe, A H; Jones, W C; Juvela, M; Keihänen, E; Keskitalo, R; Kisner, T S; Kneissl, R; Knoche, J; Knox, L; Kunz, M; Kurki-Suonio, H; Lagache, G; Lamarre, J -M; Lasenby, A; Laureijs, R J; Lawrence, C R; Leonardi, R; Leroy, C; Lesgourgues, J; Liguori, M; Lilje, P B; Linden-Vørnle, M; López-Caniego, M; Lubin, P M; Macías-Pérez, J F; MacTavish, C J; Maffei, B; Mandolesi, N; Maris, M; Marshall, D J; Martin, P G; Martínez-González, E; Masi, S; Matarrese, S; Matsumura, T; Matthai, F; Mazzotta, P; McGehee, P; Melchiorri, A; Mendes, L; Mennella, A; Migliaccio, M; Mitra, S; Miville-Deschênes, M -A; Moneti, A; Montier, L; Morgante, G; Mortlock, D; Munshi, D; Murphy, J A; Naselsky, P; Nati, F; Natoli, P; Netterfield, C B; Nørgaard-Nielsen, H U; Noviello, F; Novikov, D; Novikov, I; Osborne, S; Oxborrow, C A; Paci, F; Pagano, L; Pajot, F; Paoletti, D; Pasian, F; Patanchon, G; Perdereau, O; Perotto, L; Perrotta, F; Piacentini, F; Piat, M; Pierpaoli, E; Pietrobon, D; Plaszczynski, S; Pointecouteau, E; Polegre, A M; Polenta, G; Ponthieu, N; Popa, L; Poutanen, T; Pratt, G W; Prézeau, G; Prunet, S; Puget, J -L; Rachen, J P; Reinecke, M; Remazeilles, M; Renault, C; Ricciardi, S; Riller, T; Ristorcelli, I; Rocha, G; Rosset, C; Roudier, G; Rowan-Robinson, M; Rusholme, B; Sandri, M; Santos, D; Sauvé, A; Savini, G; Shellard, E P S; Spencer, L D; Starck, J -L; Stolyarov, V; Stompor, R; Sudiwala, R; Sureau, F; Sutton, D; Suur-Uski, A -S; Sygnet, J -F; Tauber, J A; Tavagnacco, D; Terenzi, L; Tomasi, M; Tristram, M; Tucci, M; Umana, G; Valenziano, L; Valiviita, J; Van Tent, B; Vielva, P; Villa, F; Vittorio, N; Wade, L A; Wandelt, B D; Yvon, D; Zacchei, A; Zonca, A

    2014-01-01

    This paper characterizes the effective beams,the effective beam window functions and the associated errors for the Planck HFI detectors. The effective beam is the angular response including the effect of the optics,detectors,data processing and the scan strategy. The window function is the representation of this beam in the harmonic domain which is required to recover an unbiased measurement of the CMB angular power spectrum. The HFI is a scanning instrument and its effective beams are the convolution of: (a) the optical response of the telescope and feeds;(b)the processing of the time-ordered data and deconvolution of the bolometric and electronic time response; and (c) the merging of several surveys to produce maps. The time response functions are measured using observations of Jupiter and Saturn and by minimizing survey difference residuals. The scanning beam is the post-deconvolution angular response of the instrument, and is characterized with observations of Mars. The main beam solid angles are determin...

  9. Transformation Algorithm of Dielectric Response in Time-Frequency Domain

    Ji Liu

    2014-01-01

    Full Text Available A transformation algorithm of dielectric response from time domain to frequency domain is presented. In order to shorten measuring time of low or ultralow frequency dielectric response characteristics, the transformation algorithm is used in this paper to transform the time domain relaxation current to frequency domain current for calculating the low frequency dielectric dissipation factor. In addition, it is shown from comparing the calculation results with actual test data that there is a coincidence for both results over a wide range of low frequencies. Meanwhile, the time domain test data of depolarization currents in dry and moist pressboards are converted into frequency domain results on the basis of the transformation. The frequency domain curves of complex capacitance and dielectric dissipation factor at the low frequency range are obtained. Test results of polarization and depolarization current (PDC in pressboards are also given at the different voltage and polarization time. It is demonstrated from the experimental results that polarization and depolarization current are affected significantly by moisture contents of the test pressboards, and the transformation algorithm is effective in ultralow frequency of 10−3 Hz. Data analysis and interpretation of the test results conclude that analysis of time-frequency domain dielectric response can be used for assessing insulation system in power transformer.

  10. In situ response time measurements of RTD temperature sensors

    The loop-current-step-response test provides a mean for determining the time constant of resistence thermometers. The test consist in heating the sensor a few degrees above ambient temperature by causing a step pertubation in the electric current that flows through the sensor leads. The developed mathematical transformation permits to use data collected during the internal heating transient to predict the sensor response to perturbations in fluid temperature. Experimental data obtained show that the time constant determined by method is within 15 percent of true value. The loop-current-step-response test is a remote in situ test, which can be performed with the sensor installed in the process. Consequently it takes account the local heat transfer conditions, and appropriated for nuclear power plants, where sensors are installed in points of difficult access. (author)

  11. Improvement in MFTF data base system response times

    The Supervisory Control and Diagnostic System for the Mirror Fusion Test Facility (MFTF) has been designed as an event driven system. To this end we have designed a data base notification facility in which a task can request that it be loaded and started whenever an element in the data base is changed beyond some user defined range. Our initial implementation of the notify facility exhibited marginal response times whenever a data base table with a large number of outstanding notifies was written into. In this paper we discuss the sources of the slow response and describe in detail a new structure for the list of notifies which minimizes search time resulting in significantly faster response

  12. Analog electro-optical readout of SiPMs achieves fast timing required for time-of-flight PET/MR

    Bieniosek, MF; Levin, CS

    2015-01-01

    The design of combined positron emission tomography/magnetic resonance (PET/MR) systems presents a number of challenges to engineers, as it forces the PET system to acquire data in space constrained environment that is sensitive to electro-magnetic interference and contains high static, radio frequency (RF) and gradient fields. In this work we validate fast timing performance of a PET scintillation detector using a potentially very compact, very low power, and MR compatible readout method in ...

  13. Response Times of Operators in a Control Room

    Platz, O.; Rasmussen, J.; Skanborg, Preben Zacho

    A statistical analysis was made of operator response times recorded in the control room of a research reactor during the years 1972-1974. A homogeneity test revealed that the data consist of a mixture of populations. A small but statistically significant difference is found between day and night...

  14. Mean Response Time Approximation for HTTP Transactions over Transport Protocols

    Y. J. Lee

    2014-12-01

    Full Text Available This paper addresses mean response time that end-users experience when using the Internet. HTTP (Hyper Text Transfer Protocol is a widely used transfer protocol to retrieve web objects in the Internet. Generally, HTTP uses TCP (Transmission Control Protocol in a transport layer. But it is known that HTTP interacts with TCP inefficiently. As an example of such inefficiencies, HTTP does not require TCP to deliver the rigid order, which may cause head-of-line blocking. As another transport layer protocol, SCTP (Stream Control Transmission Protocol has attractive features such as multi-streaming and multi-homing unlike TCP. Within an SCTP association, multi-streaming allows for independent delivery among streams, thus can avoid the head-of-line blocking. In addition, SCTP provides very large number of streams; therefore, it can transfer multiple objects more efficiently than the typical HTTP/1.1 over TCP which limits the number of pipelines. Mean response time is one of the main measures that end users using Internet concern. This paper presents the simple analytical model and algorithm to find the mean response time for HTTP over SCTP including the previous HTTP over TCP. Some computational experiences show that the proposed model and algorithm are well approximated to the real environment. Also, it is shown that mean response time for HTTP over SCTP can be less than that for HTTP over TCP.

  15. Processing Time Shifts Affects the Execution of Motor Responses

    Sell, Andrea J.; Kaschak, Michael P.

    2011-01-01

    We explore whether time shifts in text comprehension are represented spatially. Participants read sentences involving past or future events and made sensibility judgment responses in one of two ways: (1) moving toward or away from their body and (2) pressing the toward or away buttons without moving. Previous work suggests that spatial…

  16. Linear-response thermal time-dependent density functional theory

    Pribram-Jones, Aurora; Burke, Kieron

    2015-01-01

    The van Leeuwen proof of linear-response time-dependent density functional theory (TDDFT) is generalized to thermal ensembles. This allows generalization to finite temperatures of the Gross-Kohn relation, the exchange-correlation kernel of TDDFT, and fluctuation dissipation theorem for DFT. This produces a natural method for generating new thermal exchange-correlation (XC) approximations.

  17. Optimization of the Time Response of LaBr3(Ce) Detectors, and Its Dependence on Ce Concentration

    Vedia, V.; Mach, H.; Fraile, L. M.; Lalkovski, S.; Udías, J. M.

    Fast inorganic scintillators that exhibit good spectroscopy performance, like LaBr3(Ce), are the crystals of choice for many applications; they play a crucial role in the Ultra Fast Timing technique by virtue of their good energy resolution and fast response [1]. This method, which is very sensitive to the LaBr3(Ce) time resolution, allows measurements of nuclear level lifetimes down to few ps range. There are indications that the nominal Ce concentration does strongly influence on the timing properties as well as it varies the photon yield and the energy resolution [2]. In this work we have searched for the best settings in order to optimize the time resolution of three cylindrical LaBr3(Ce) detectors equipped with crystals identical in volume and shape but with different Ce dopant concentration. The time resolution of every detector depends on the proper selection of the fast photomultiplier tube and the set up parameters that can be further optimized by fine-tuning of the Constant Fraction Discrimination (CFD) and the PMT bias voltage. Very good time resolution can be obtained with the ORTEC 935 CFD for very short time-delays. Timing properties of the three crystals were studied by delayed coincidence measurements against a reference BaF2 detector, whose time response is well known. The LaBr3(Ce) detector and the reference unit were placed in a close geometry with the radioactive source in between. We report timing results measured at the 60Co and 22Na energies.

  18. Comparison of LMFBR piping response obtained using response spectrum and time history methods

    The dynamic response to a seismic event is calculated for a piping system using a response spectrum analysis method and two time history analysis methods. The results from the analytical methods are compared to identify causes for the differences between the sets of analytical results. Comparative methods are also presented which help to gain confidence in the accuracy of the analytical methods in predicting piping system structure response during seismic events

  19. Aircraft Fault Detection Using Real-Time Frequency Response Estimation

    Grauer, Jared A.

    2016-01-01

    A real-time method for estimating time-varying aircraft frequency responses from input and output measurements was demonstrated. The Bat-4 subscale airplane was used with NASA Langley Research Center's AirSTAR unmanned aerial flight test facility to conduct flight tests and collect data for dynamic modeling. Orthogonal phase-optimized multisine inputs, summed with pilot stick and pedal inputs, were used to excite the responses. The aircraft was tested in its normal configuration and with emulated failures, which included a stuck left ruddervator and an increased command path latency. No prior knowledge of a dynamic model was used or available for the estimation. The longitudinal short period dynamics were investigated in this work. Time-varying frequency responses and stability margins were tracked well using a 20 second sliding window of data, as compared to a post-flight analysis using output error parameter estimation and a low-order equivalent system model. This method could be used in a real-time fault detection system, or for other applications of dynamic modeling such as real-time verification of stability margins during envelope expansion tests.

  20. Statistical Tests of Conditional Independence between Responses and/or Response Times on Test Items

    van der Linden, Wim J.; Glas, Cees A. W.

    2010-01-01

    Three plausible assumptions of conditional independence in a hierarchical model for responses and response times on test items are identified. For each of the assumptions, a Lagrange multiplier test of the null hypothesis of conditional independence against a parametric alternative is derived. The tests have closed-form statistics that are easy to…

  1. The Time Course Effect of Moderate Intensity Exercise on Response Execution and Response Inhibition

    Joyce, Jennifer; Graydon, Jan; McMorris, Terry; Davranche, Karen

    2009-01-01

    This research aimed to investigate the time course effect of a moderate steady-state exercise session on response execution and response inhibition using a stop-task paradigm. Ten participants performed a stop-signal task whilst cycling at a carefully controlled workload intensity (40% of maximal aerobic power), immediately following exercise and…

  2. Fast three-dimensional imaging of the pituitary gland with very short echo times: Elimination of magnetic susceptibility artifacts

    New fast gradient echo sequences have recently made it possible to perform true/isotropic volume imaging in a clinically acceptable examination time, making it ideal for pituitary evaluation. The problem to date, however, has been the sensitivity of the gradient echo to magnetic susceptibility, which occurs in the parasellar region. Magnetic susceptibility can cause areas of signal void and totally obscure the brain base and pituitary gland. This paper proposes a method whereby very short echo time sequences (5-6 msec) eliminate magnetic susceptibility artifacts, allowing high-resolution isotropic evaluation of the pituitary gland

  3. Fast Pyrolysis Behavior of Banagrass as a Function of Temperature and Volatiles Residence Time in a Fluidized Bed Reactor

    Trevor James Morgan; Scott Q Turn; Anthe George

    2015-01-01

    A reactor was designed and commissioned to study the fast pyrolysis behavior of banagrass as a function of temperature and volatiles residence time. Four temperatures between 400 and 600°C were examined as well as four residence times between ~1.0 and 10 seconds. Pyrolysis product distributions of bio-oil, char and permanent gases were determined at each reaction condition. The elemental composition of the bio-oils and chars was also assessed. The greatest bio-oil yield was recorded when work...

  4. Processes in current sheets responsible for fast energy conversion in the magnetospheric collisionless plasma

    Kropotkin, Alexey

    2013-01-01

    Dynamics of the magnetospheric plasma configuration intrinsically features intermittent slow and fast phases. The fast transition is a nonlinear process, loss of equilibrium which ends up the slow quasi-static evolution. The process is analysed as a dynamical bifurcation. It appears when marginal stability state is reached in the course of that evolution, either for tearing mode or for ballooning mode disturbances. The resulting force imbalance leads to spontaneous formation of nonlinear kinetic thin current structures. Those are either a pair of slow collisionless shocks or a specific anisotropic thin current sheet embedded in a thicker plasma sheet structure. Both are the sites of intense energy conversion, and they implement fast magnetic reconnection in the magnetospheric collisionless plasma.

  5. Evaluation of fluid effects on the dynamic response of a fast reactor core

    The results of dynamic experiments on shaking tables, carried out in water (simulating sodium) on both single and coupled core element prototypes and core simplified mock-up configurations of the Italian PEC fast reactor test facility, with excitation gradually increasing up to above Safe Shutdown Earthquake, have been analysed by use of the one-dimensional computer program CORALIE and the two-dimensional program CLASH. The study confirmed the conservative nature of the PEC core design calculations, provided the natural frequency and damping values to be used in the calculations for the Final Safety Report, and allowed the fluid-structure interaction model to be assessed for the PEC core seismic analysis. It also contributed to the validation of the above-mentioned computer codes for their general use for the fast reactor core analysis as well as to a better understanding of fluid-structure interaction problems concerning the fast reactor core

  6. Effect of training in the fasted state on metabolic responses during exercise with carbohydrate intake

    De Bock, K; Derave, W; Eijnde, B O;

    2008-01-01

    program (6 wk, 3 day/wk, 1-2 h, 75% of peak Vo(2)) in moderately active males. They trained in the fasted (F; n = 10) or carbohydrate-fed state (CHO; n = 10) while receiving a standardized diet [65 percent of total energy intake (En) from carbohydrates, 20%En fat, 15%En protein]. Before and after the...... training period, substrate use during a 2-h exercise bout was determined. During these experimental sessions, all subjects were in a fed condition and received extra carbohydrates (1 g.kg body wt(-1) .h(-1)). Peak Vo(2) (+7%), succinate dehydrogenase activity, GLUT4, and hexokinase II content were...... elicits similar adaptations in peak Vo(2) whether carried out in the fasted or carbohydrate-fed state. Although there was a decrease in exercise-induced glycogen breakdown and an increase in proteins involved in fat handling after fasting training, fat oxidation during exercise with carbohydrate intake...

  7. Predicting aquifer response time for application in catchment modeling.

    Walker, Glen R; Gilfedder, Mat; Dawes, Warrick R; Rassam, David W

    2015-01-01

    It is well established that changes in catchment land use can lead to significant impacts on water resources. Where land-use changes increase evapotranspiration there is a resultant decrease in groundwater recharge, which in turn decreases groundwater discharge to streams. The response time of changes in groundwater discharge to a change in recharge is a key aspect of predicting impacts of land-use change on catchment water yield. Predicting these impacts across the large catchments relevant to water resource planning can require the estimation of groundwater response times from hundreds of aquifers. At this scale, detailed site-specific measured data are often absent, and available spatial data are limited. While numerical models can be applied, there is little advantage if there are no detailed data to parameterize them. Simple analytical methods are useful in this situation, as they allow the variability in groundwater response to be incorporated into catchment hydrological models, with minimal modeling overhead. This paper describes an analytical model which has been developed to capture some of the features of real, sloping aquifer systems. The derived groundwater response timescale can be used to parameterize a groundwater discharge function, allowing groundwater response to be predicted in relation to different broad catchment characteristics at a level of complexity which matches the available data. The results from the analytical model are compared to published field data and numerical model results, and provide an approach with broad application to inform water resource planning in other large, data-scarce catchments. PMID:24842053

  8. Physiological adaptive indicators in fasted neonate broiler chicks in response to calcium gluconate injection.

    Khosravinia, H

    2016-06-01

    Four hundred and eighty mixed-sex broiler chicks aged 3 h after hatching were allotted according to a completely random design in a 6 × 2 × 2 factorial schedule into two groups of 12 replications of 20 chicks each. The main experimental factors were fasting for 0, 6, 12, 24, 36 and 48 h after chick placement and calcium gluconate (Ca-glu) injection (0 and 0.6 ml). Live body weight (BW) of chicks decreased linearly (Y = 43.36-0.109BW0 h , r(2)  = 0.876) as neonatal fasting extended. Injection of 0.6 ml Ca-glu at 3 h post-hatching did not affect weight loss of chicks. Yolk residuals (YR) utilized linearly (Y = 5.75-0.062YR, r(2)  = 0.956) by 0.062 g/h in neonate fasted chicks up to 48 h, showing no effect of Ca-glu injection. Neonatal fasting periods longer than 12 h increased liver weight (p < 0.05). The mean absolute and proportional (% of BW0 h ) breast and leg weight were reduced linearly as neonatal fasting extended (p < 0.05). Serum glucose concentration increased up to 6 h and then reduced linearly to 150 mg/dl after 48-h fasting. The Ca-glu treatment influenced serum glucose level for a short period up to 6 h of fasting. Serum Ca concentration sharply increased up to threefolds in the birds received Ca-glu injection resulting in acute hypercalcemia, then decreased to the initial level after 24-h feed withdrawal (p < 0.05). The mean serum level for creatinine, uric acid, cholesterol, HDL, albumins and total proteins significantly increased during the fasting periods of 6 to 48 h and significantly elevated in the birds receiving 0.6-ml Ca-glu injection compared with the non-treated chicks (p < 0.05). It was concluded that subcutaneous administration of 0.6 ml Ca-glu in the chick's neck did not suitably support the increased metabolic demands for glucose and calcium in feed-deprived neonate chicks. PMID:26344414

  9. The noise-time of response compromise in d.c. period meters. A new type of circuit (1961)

    The report compares the characteristics of three period meter circuits: - a linear circuit - a circuit which is non-linear according to the nuclear reactor period - a circuit which is non-linear according to the period and the power of the reactor. This last type of reactor has a fast time of response if the power is high or if the period is short, and it has a slow time of response when the power is low and the period long; this system makes it possible to maintain the noise at an acceptable level under all normal working conditions of the reactor. (author)

  10. Analog electro-optical readout of SiPMs achieves fast timing required for time-of-flight PET/MR

    Bieniosek, M. F.; Levin, C. S.

    2015-05-01

    The design of combined positron emission tomography/magnetic resonance (PET/MR) systems presents a number of challenges to engineers, as it forces the PET system to acquire data in a space constrained environment that is sensitive to electro-magnetic interference and contains high static, radio frequency and gradient fields. In this work we validate fast timing performance of a PET scintillation detector using a potentially very compact, very low power, and MR compatible readout method in which analog silicon photomultipliers (SiPM) signals are transmitted optically away from the MR bore with little or even no additional readout electronics. This analog ‘electro-optial’ method could reduce the entire PET readout in the MR bore to two compact, low power components (SiPMs and lasers). Our experiments show fast timing performance from analog electro-optical readout with and without pre-amplification. With 3 mm × 3 mm × 20 mm lutetium-yttrium oxyorthosilicate (LYSO) crystals and Excelitas SiPMs the best two-sided fwhm coincident timing resolution achieved was 220 +/- 3 ps in electrical mode, 230 +/- 2 ps in electro-optical with preamp mode, and 253 +/- 2 ps in electro-optical without preamp mode. Timing measurements were also performed with Hamamatsu SiPMs and 3 mm × 3 mm × 5 mm crystals. In the future the timing degradation seen can be further reduced with lower laser noise or improvements SiPM rise time or gain.

  11. The Fast Simulation Chain for ATLAS

    Basalaev, Artem; The ATLAS collaboration

    2016-01-01

    In order to generate the huge number of Monte Carlo events that will be required by the ATLAS experiment over the next several runs, a very fast simulation is critical. Fast detector simulation alone, however, is insufficient: with very high numbers of simultaneous proton-proton collisions expected in Run 3 and beyond, the digitization (detector response emulation) and event reconstruction time quickly become comparable to the time required for detector simulation. The ATLAS Fast Chain simulation has been developed to solve this problem. Modules are implemented for fast simulation, fast digitization, and fast track reconstruction. The application is sufficiently fast -- several orders of magnitude faster than the standard simulation -- that the simultaneous proton-proton collisions can be generated during the simulation job, so Pythia8 also runs concurrently with the rest of the algorithms. The Fast Chain has been built to be extremely modular and flexible, so that each sample can be custom-tailored to match ...

  12. Early stage time evolution of a dense nanosecond microdischarge used in fast optical switching applications

    Levko, Dmitry; Raja, Laxminarayan L. [Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, Austin, Texas 78712 (United States)

    2015-12-15

    The mechanism of high-voltage nanosecond microdischarges is studied by the self-consistent two-dimensional Particle-in-Cell/Monte Carlo Collisions model. These microdischarges were recently proposed for use as fast switches of visible light in Bataller et al. [Appl. Phys. Lett. 105, 223501 (2014)]. The microdischarge is found to develop in two stages. The first stage is associated with the electrons initially seeded in the cathode-anode gap. These electrons lead to the formation of a cathode-directed streamer. The second stage starts when the secondary electron emission from the cathode begins. In this stage, a rather dense plasma (∼10{sup 16 }cm{sup −3}) is generated which results in the narrow cathode sheath. The electric field in this sheath exceeds the critical electric field which is necessary for the runaway electrons generation. We have found that the presence of these energetic electrons is crucial for the discharge maintenance.

  13. Time Trends in Fast Food Consumption and Its Association with Obesity among Children in China.

    Hong Xue

    Full Text Available Study the trends in Western fast food consumption (FFC among Chinese school-age children and the association between FFC and obesity using nationwide survey data.Cross-sectional and longitudinal analyses were conducted to study the trends in FFC and the associations between FFC and weight status (overweight, obesity and body mass index (BMI z-score.Longitudinal data from families were collected in the 2004 and 2009 China Health and Nutrition Survey (covering nine provinces throughout China.The analysis included 2656 Chinese children aged 6 to 18 years (1542 and 1114 children in the 2004 and 2009 survey, respectively.FFC (reported having consumed Western fast food in the past three months has increased between 2004 and 2009, from 18.5% to 23.9% in those aged 6-18, and increased more rapidly among those aged 13-17, from 17.9% to 26.3%. The increase was significant in almost all groups by age, sex, family income, and residence. Our cross-sectional and longitudinal analyses did not detect a significant association between FFC and obesity/overweight or BMI z-score (e.g., for BMI z-score, boys: β = 0.02, 95% CI: -0.71, 0.75; girls: β = -0.14, 95% CI: -1.03, 0.75.FFC has increased in Chinese school-age children, especially in older children, boys, and those from low- and medium-income families, rural areas, and East China, but decreased among those from high-income families during 2004-2009. The data did not show a significant association between FFC and obesity.

  14. Metabolomics reveals differences in postprandial responses to breads and fasting metabolic characteristics associated with postprandial insulin demand in postmenopausal women.

    Moazzami, Ali A; Shrestha, Aahana; Morrison, David A; Poutanen, Kaisa; Mykkänen, Hannu

    2014-06-01

    Changes in serum metabolic profile after the intake of different food products (e.g., bread) can provide insight into their interaction with human metabolism. Postprandial metabolic responses were compared after the intake of refined wheat (RWB), whole-meal rye (WRB), and refined rye (RRB) breads. In addition, associations between the metabolic profile in fasting serum and the postprandial concentration of insulin in response to different breads were investigated. Nineteen postmenopausal women with normal fasting glucose and normal glucose tolerance participated in a randomized, controlled, crossover meal study. The test breads, RWB (control), RRB, and WRB, providing 50 g of available carbohydrate, were each served as a single meal. The postprandial metabolic profile was measured using nuclear magnetic resonance and targeted LC-mass spectrometry and was compared between different breads using ANOVA and multivariate models. Eight amino acids had a significant treatment effect (P bread (cross-validated ANOVA, P = 0.048). High blood concentration of branched-chain amino acids, i.e., leucine and isoleucine, has been associated with the increased risk of diabetes, which suggests that additional consideration should be given to bread proteins in understanding the beneficial health effects of different kinds of breads. The present study suggests that the fasting metabolic profile can be used to characterize the postprandial insulin demand in individuals with normal glucose metabolism that can be used for establishing strategies for the stratification of individuals in personalized nutrition. PMID:24717363

  15. The effect of alcohol hangover on choice response time

    Grange, JA; Stephens, R.; Jones, K; Owen, L

    2016-01-01

    The effect of alcohol hangover on cognitive processing has received little attention. We explored the effect of alcohol hangover on choice response time (RT), a dominant dependent variable (DV) in cognitive research. Prior research of the effect of hangover on RT has produced mixed findings; all studies reviewed relied exclusively on estimates of central tendency (e.g. mean RT), which has limited information value. Here we present novel analytical methods by going beyond mean RT analysis. Spe...

  16. Response Time Analysis of Distributed Web Systems Using QPNs

    Tomasz Rak

    2015-01-01

    Full Text Available A performance model is used for studying distributed Web systems. Performance evaluation is done by obtaining load test measurements. Queueing Petri Nets formalism supports modeling and performance analysis of distributed World Wide Web environments. The proposed distributed Web systems modeling and design methodology have been applied in the evaluation of several system architectures under different external loads. Furthermore, performance analysis is done to determine the system response time.

  17. The time-dependence of electromagnetic response functions

    Beamish, D.

    1982-01-01

    Dynamic processes within the Earth are capable of modifying many of its physical properties. This review considers the modification of electrical resistivity mainly by time-changes in the stress­ field experienced by crustal materials. Laboratory experiments indicate that certain rock types, whose resistivity is controlled by the volume and geometry of microcracks, can undergo large resistivity variations in response to the typical strain accumulation and release that accompanies major ear...

  18. Development of time-of-flight neutron detector with fast-decay and low-afterglow scintillator for fast ignition experiment

    Nagai T.

    2013-11-01

    Full Text Available A fast-decay and low-afterglow liquid scintillator was developed for the fast ignition experiment at the Institute of Laser Engineering (ILE. The liquid scintillator was coupled to a gated photomultiplier (PMT, and the gating performance under high-intensity γ-rays was experimentally checked. In 2010, a detector with a high detection efficiency of 10−4 was developed and installed in this experiment. The neutron yield in the fast heating experiment was successfully measured using this detector.

  19. No Time to Lose? Time Shrinking Effects enhance the Impression of Rhythmic "Isochrony" and Fast Speech Rate

    Wagner, Petra; Windmann, Andreas

    2009-01-01

    Time Shrinking denotes the psychoacoustic shrinking effect of a short interval on one or several subsequent longer intervals. Its effectiveness in the domain of speech perception has so far not been examined. Two perception experiments clearly suggest the influence of relative duration patterns triggering time shrinking on the perception of tempo and rhythmical isochrony or rather ”evenness”. A comparison between the experimental data and duration patterns across various languages sugges...

  20. Linear response characteristics of time-dependent time fractional Fokker–Planck equation systems

    The time fractional Fokker–Planck equation approach is an important tool for modeling subdiffusion. When the external field is time modulated, two types of time-dependent time fractional Fokker–Planck equations have been proposed, both reduced to the same time-dependent time fractional Fokker–Planck equation when the external field is time uncorrelated. The first type is strictly deduced as the continuous limit of the continuous time random walk with time modulated Boltzmann jumping weight, while the second type is derived by ideally assuming that the jump probabilities can be evaluated at the start of the waiting time prior to jumping. For the first time we obtain the linear response characteristic for the first type of the time fractional Fokker–Planck equation systems, and for a comparison we revisit the corresponding result for the second type of the time fractional Fokker–Planck equation systems, and the similarity and difference between them is discussed with an application example. The investigation not only helps in understanding the competition between subdiffusion and time-dependent modulation, but also has significance in accessing the spectral properties of spontaneous fluctuation and the linear dynamic susceptibility of external perturbation in subdiffusive processes. (paper)

  1. Development of a fast plastic scintillation detector with time resolution of less than 10 ps

    Zhao, J W; Tanihata, I; Terashima, S; Zhu, L H; Enomoto, A; Nagae, D; Nishimura, T; Omika, S; Ozawa, A; Takeuchi, Y; Yamaguchi, T

    2016-01-01

    Timing-pick up detectors with excellent timing resolutions are essential in many modern nuclear physics experiments. Aiming to develop a Time-Of-Flight system with precision down to about 10 ps, we have made a systematic study of the timing characteristic of TOF detectors, which consist of several combinations of plastic scintillators and photomultiplier tubes. With the conventional electronics, the best timing resolution of about 5.1 ps ({\\sigma}) has been achieved for detectors with an area size of 3x1 cm2. It is found that for data digitalization a combination of TAC and ADC can achieve a better time resolution than currently available TDC. Simultaneously measurements of both time and pulse height are very valuable for correction of time-walk effect.

  2. A dynamic-biased dual-loop-feedback CMOS LDO regulator with fast transient response

    Han, Wang; Maomao, Sun

    2014-04-01

    This paper presents a low-dropout regulator (LDO) for portable applications with dual-loop feedback and a dynamic bias circuit. The dual-loop feedback structure is adopted to reduce the output voltage spike and the response time of the LDO. The dynamic bias circuit enhances the slew rate at the gate of the power transistor. In addition, an adaptive miller compensation technique is employed, from which a single pole system is realized and over a 59° phase margin is achieved under the full range of the load current. The proposed LDO has been implemented in a 0.6-μm CMOS process. From the experimental results, the regulator can operate with a minimum dropout voltage of 200 mV at a maximum 300 mA load and IQ of 113 μA. The line regulation and load regulation are improved to 0.1 mV/V and 3.4 μV/mA due to the sufficient loop gain provided by the dual feedback loops. Under a full range load current step, the voltage spikes and the recovery time of the proposed LDO is reduced to 97 mV and 0.142 μs respectively.

  3. Fast X-Ray Timing: A Window into the Strong-Field Regime

    Strohmayer, Tod

    2010-01-01

    The dynamical time-scales in the vicinity of neutron star surfaces and black hole horizons are in the millisecond range. Over the past decade, timing signatures on such scales, either quasi-periodic oscillations (QPOs) and/or coherent pulsations, have been discovered and studied from both neutron stars and black holes with NASA's Rossi X-ray Timing Explorer, Although theoretical interpretations are still hotly debated, these timing properties almost certainly reflect the dynamics of matter in regions dominated by relativistic gravity. I will survey our current understanding of these timing properties, with a focus on how they might he used as probes of fundamental physics.

  4. LHCb: Beam and Background Monitoring and the Upgrade of the Timing and Fast Control System of the LHCb experiment at CERN

    Alessio, F

    2009-01-01

    The LHCb experiment at CERN is preparing for first real data taking, foreseen by the end of the year 2009 with the start-up of the LHC. A large amount of work of commissioning, tests and improvements of the full detector has been done in order to optimize its performance. During my first year as a Doctoral Student at CERN, I have been working on the timing and readout control of the LHCb experiment in the frame of the LHCb Online group. The group is responsible for the full data acquisition of the LHCb experiment, from the Front-End Electronics (FEE) to the storage of the data for offline analysis, as well as the Timing and Fast Control (TFC) system. The latter controls and distributes centrally timing and trigger information, as well as synchronous and asynchronous commands to the readout system. It is also responsible for receiving and adjusting the bunch and orbit clocks of the LHC machine and distributing it to the electronics of the whole experiment. It is of vital importance to assure that the timing o...

  5. Influence of the Helicopter Time Domain Electromagnetic System Off-Time Response by the Transmitter Assembly

    Vetrov, A.; Mejzr, I.

    2010-12-01

    While developing a new Helicopter Time Domain Electromagnetic system (P-THEM), Pico Envirotec Inc (PEI) has studied the effect of the transmitter assembly on the acquired data. The P-THEM system consists of a loop-transmitter assembly, powered by a motor generator, 3-axis coil receiver attached at the midpoint of a tow cable and an additional Z-axis (dB/dt) receiver installed on the rear section of the transmitter loop. The system is towed by a helicopter on a 230 foot long tow cable. The transmitter loop is designed to produce a peak magnetic moment of approximately 250,000 NIA with a base frequency of 30 Hz (adjustable to 25Hz) and a quarter length duty cycle (4 ms on-time). The secondary field acquired with a dB/dt receiver coil consists of a ground response and a system response: SF=Rg+Rsys, where SF - the secondary field, Rg - ground response, Rsys - system response. The system itself, especially the transmitter assembly, being a conductor in an induced magnetic field, creates a magnetic anomaly. The influence of the transmitter assembly anomaly on the received signal depends on the position of the receiver coil against the transmitter, the intensity of on-time pulse and transmitter electro-magnetic properties. At the same time, the ground response acquired with a receiver coil depends on the length and the moment of transmitter pulse, as well as the position and distance of the receiver coil from the ground. This can be for vertical field (Z) receiver coil described as RXz(t)=e(t)pz(t)Rgz(t)+d(t)k(t)j(t)TXz(t), where RXz(t) - receiver response, e(t) - elevation of the receiver over the ground, pz(t) - horizontal projection of the receiver coil, Rgz(t) - vertical component of ground response, d(t) - distance (elevation) between the receiver coil and the transmitter loop, k(t) - the position of the receiver in the transmitter field, j(t) - the transmitter assembly electromagnetic properties, TXz(t) -transmitter field (Primary field on-time, and transmitter

  6. A search for Fast Radio Bursts at low frequencies with Murchison Widefield Array high time resolution imaging

    Tingay, S. J.; Trott, C. M.; Wayth, R. B.; Bernardi, G.; Bowman, J. D.; Briggs, F.; Cappallo, R. J.; Deshpande, A.A.; Feng, L.; Gaensler, B.M.; Greenhill, L. J.; Hancock, P. J.; Hazelton, B. J.; Johnston-Hollitt, M.; Kaplan, D.L.

    2015-01-01

    We present the results of a pilot study search for Fast Radio Bursts (FRBs) using the Murchison Widefield Array (MWA) at low frequencies (139 - 170 MHz). We utilised MWA data obtained in a routine imaging mode from observations where the primary target was a field being studied for Epoch of Reionisation detection. We formed images with 2 second time resolution and 1.28~MHz frequency resolution for 10.5 hours of observations, over 400 square degrees of the sky. We de-dispersed the dynamic spec...

  7. Parametric control of structural vibrations and sound radiation by fast time-space variation of distributed stiffness parameters

    The dynamics of a Euler-Bernoulli beam with a time-and-space dependent bending stiffness is studied. The , problem is considered in connection with the application of noise control using smart structures. It is shown that a control for the vibrations of the beam can be achieved by varying the bending stiffness. The technique of direct separation of fast and slow motion coupled with a Green's function method is used to analyze the dynamics of the beam with high-frequency modulation of the stiffness

  8. Real-time Pricing Demand Response in Operations

    Widergren, Steven E.; Marinovici, Maria C.; Berliner, Teri; Graves, Alan

    2012-07-26

    Abstract—Dynamic pricing schemes have been implemented in commercial and industrial application settings, and recently they are getting attention for application to residential customers. Time-of-use and critical-peak-pricing rates are in place in various regions and are being piloted in many more. These programs are proving themselves useful for balancing energy during peak periods; however, real-time (5 minute) pricing signals combined with automation in end-use systems have the potential to deliver even more benefits to operators and consumers. Besides system peak shaving, a real-time pricing system can contribute demand response based on the locational marginal price of electricity, reduce load in response to a generator outage, and respond to local distribution system capacity limiting situations. The US Department of Energy (DOE) is teaming with a mid-west electricity service provider to run a distribution feeder-based retail electricity market that negotiates with residential automation equipment and clears every 5 minutes, thus providing a signal for lowering or raising electric consumption based on operational objectives of economic efficiency and reliability. This paper outlines the capability of the real-time pricing system and the operational scenarios being tested as the system is rolled-out starting in the first half of 2012.

  9. Formulation and optimization of fast dissolving intraoral drug delivery system for clobazam using response surface methodology

    Rajni Bala; Sushil Khanna; Pawar, Pravin K

    2013-01-01

    Clobazam is a newer 1,5-benzodiazepine used for the treatment of epilepsy. It is better tolerated and less sedating than other benzodiazepines. Absorption of the drug can be impacted by oral fast dissolving dosage form; this may have implications for epilepsy in pediatrics and those having difficulty in swallowing tablets/capsules resulting in improved patient compliance. The purpose of the present investigation was to formulate and optimize clobazam oro-dissolving tablets by direct compressi...

  10. Fuel pins and core response under liquid-metal fast breeder reactor transient overpower accident conditions

    Since the earlier liquid-metal fast breeder reactor transient overpower assessments were done (1975), new experimental data and modeling improvements have occurred that indicate later failures and more molten fuel squirted into the channel with a higher propensity for plugging. An initial sweepout still occurs, and an analysis shows that even if coherent instead of the expected stochastic failures occur, the blockages are partial, the reactor is strongly shut down, and a coolable geometry exists. Hence, the overall consequences would be benign

  11. Characterisation of nanoparticle emissions and exposure at traffic intersections through fast-response mobile and sequential measurements

    Goel, Anju; Kumar, Prashant

    2015-04-01

    Quantification of disproportionate contribution made by signalised traffic intersections (TIs) to overall daily commuting exposure is important but barely known. We carried out mobile measurements in a car for size-resolved particle number concentrations (PNCs) in the 5-560 nm range under five different ventilation settings on a 6 km long busy round route with 10 TIs. These ventilation settings were windows fully open and both outdoor air intake from fan and heating off (Set1), windows closed, fan 25% on and heating 50% on (Set2), windows closed, fan 100% on and heating off (Set3), windows closed, fan off and heating 100% on (Set4), and windows closed, fan and heating off (Set5). Measurements were taken sequentially inside and outside the car cabin at 10 Hz sampling rate using a solenoid switching system in conjunction with a fast response differential mobility spectrometer (DMS50). The objectives were to: (i) identify traffic conditions under which TIs becomes hot-spots of PNCs, (ii) assess the effect of ventilation settings in free-flow and delay conditions (waiting time at a TI when traffic signal is red) on in-cabin PNCs with respect to on-road PNCs at TIs, (iii) deriving the relationship between the PNCs and change in driving speed during delay time at the TIs, and (iv) quantify the contribution of exposure at TIs with respect to overall commuting exposure. Congested TIs were found to become hot-spots when vehicle accelerate from idling conditions. In-cabin peak PNCs followed similar temporal trend as for on-road peak PNCs. Reduction in in-cabin PNC with respect to outside PNC was highest (70%) during free-flow traffic conditions when both fan drawing outdoor air into the cabin and heating was switched off. Such a reduction in in-cabin PNCs at TIs was highest (88%) with respect to outside PNC during delay conditions when fan was drawing outside air at 25% on and heating was 50% on settings. PNCs and change in driving speed showed an exponential

  12. Fast Monte Carlo Estimation of Timing Yield: Importance Sampling with Stochastic Logical Effort (ISLE)

    Bayrakci, Alp Arslan; Tasiran, Serdar

    2008-01-01

    In the nano era in integrated circuit fabrication technologies, the performance variability due to statistical process and circuit parameter variations is becoming more and more significant. Considerable effort has been expended in the EDA community during the past several years in trying to cope with the so-called statistical timing problem. Most of this effort has been aimed at generalizing the static timing analyzers to the statistical case. In this paper, we take a pragmatic approach in pursuit of making the Monte Carlo method for timing yield estimation practically feasible. The Monte Carlo method is widely used as a golden reference in assessing the accuracy of other timing yield estimation techniques. However, it is generally believed that it can not be used in practice for estimating timing yield as it requires too many costly full circuit simulations for acceptable accuracy. In this paper, we present a novel approach to constructing an improvedMonte Carlo estimator for timing yield which provides the...

  13. Fast and Robust Control of Excitation Systems:A Finite-time Method

    WANG Yu-zhen; CHENG Dai-zhan; HONG Yi-guang; QIN Hua-shu

    2001-01-01

    Using finite-time control approach, this paper proposes a new design method for nonlinear robust excitation control of a widely used 5th-order model of synchronous generators. The finite-time excitation controller achieved here can improve the system's behaviors in some aspects such as quick convergence and robustness for uncertainties. Simulations demonstrate that the finite-time excitation controller is more effective than some other excitation controllers.

  14. Fast Tracker : A Hardware Real Time Track Finder for the ATLAS Trigger System

    Kimura, N; The ATLAS collaboration

    2013-01-01

    The Large Hadron Collider (LHC) after the 2013-­‐2014 shutdown period is expected to improve the yet impressive performance obtained up to this year: collisions’ energy will increase to 14 TeV and instantaneous luminosity will reach and then overcome 10^34 cm‐2s‐1, with a bunch crossing period of 25 ns. The LHC experiments will need to adapt to the more crowded events, maintaining the physics output and the quality of the final results. The pileup higher than the LHC run 1, with peaks expected to reach 50 or more, will make more difficult to have efficient online selection of rare events based mostly on calorimeters and muon detectors as it is done now. A more extensive use of the information collected by the tracking detector will allow building more robust selections, limiting the degradation effects due to the high pileup. We report on the development of the Fast Tracker (FTK) processor for the ATLAS experiment, devoted to reconstruct tracks with transverse momentum above 1 GeV in the whole detect...

  15. Improved target detection and bearing estimation utilizing fast orthogonal search for real-time spectral analysis

    The problem of target detection and tracking in the ocean environment has attracted considerable attention due to its importance in military and civilian applications. Sonobuoys are one of the capable passive sonar systems used in underwater target detection. Target detection and bearing estimation are mainly obtained through spectral analysis of received signals. The frequency resolution introduced by current techniques is limited which affects the accuracy of target detection and bearing estimation at a relatively low signal-to-noise ratio (SNR). This research investigates the development of a bearing estimation method using fast orthogonal search (FOS) for enhanced spectral estimation. FOS is employed in this research in order to improve both target detection and bearing estimation in the case of low SNR inputs. The proposed methods were tested using simulated data developed for two different scenarios under different underwater environmental conditions. The results show that the proposed method is capable of enhancing the accuracy for target detection as well as bearing estimation especially in cases of a very low SNR

  16. Improved target detection and bearing estimation utilizing fast orthogonal search for real-time spectral analysis

    Osman, Abdalla; Nourledin, Aboelamgd; El-Sheimy, Naser; Theriault, Jim; Campbell, Scott

    2009-06-01

    The problem of target detection and tracking in the ocean environment has attracted considerable attention due to its importance in military and civilian applications. Sonobuoys are one of the capable passive sonar systems used in underwater target detection. Target detection and bearing estimation are mainly obtained through spectral analysis of received signals. The frequency resolution introduced by current techniques is limited which affects the accuracy of target detection and bearing estimation at a relatively low signal-to-noise ratio (SNR). This research investigates the development of a bearing estimation method using fast orthogonal search (FOS) for enhanced spectral estimation. FOS is employed in this research in order to improve both target detection and bearing estimation in the case of low SNR inputs. The proposed methods were tested using simulated data developed for two different scenarios under different underwater environmental conditions. The results show that the proposed method is capable of enhancing the accuracy for target detection as well as bearing estimation especially in cases of a very low SNR.

  17. Development of fast wave systems tolerant of time-varying loading

    A new approach to fast wave antenna array design based on the traveling wave antenna has been successfully demonstrated on the JFT-2M tokamak. A traveling wave antenna is powered though a single feed and the power flow from element to element is only via mutual reactive coupling. A combine is a particular type of traveling wave antenna, in which only the fed element and the element at the downstream end of the array are connected to vacuum feed troughs, while the intermediate elements are terminated with reactances inside the vacuum chamber. A twelve element combine for operation at 200 MHz was designed and fabricated at General Atomics, and installed and operated on the JFT-2M tokamak. The full output power of a single transmitter, 0.2 MW, was coupled to tokamak discharges with very little conditioning required. The input impedance of the combine was well matched to the transmission line impedance for all loading conditions, including vacuum (no plasma), Taylor discharge cleaning plasmas, and ohmic, L- and H-mode tokamak discharges with neutral beam heating without any adjustment of tuning elements

  18. R and D on a New Technology of Micro-pattern Gaseous Detectors Fast Timing Micro-pattern Detector

    Salva Diblen, Sinem

    2016-01-01

    After the upgrades of the Large Hadron Collider (LHC) planned for the second and the third Long Shutdown (LS), the LHC luminosity will approach very high values. Such conditions will affect the performance of the CMS muon system, especially in the very forward region, due to the harsh expected background environment and high pile-up conditions. The CMS collaboration considers upgrading the muon forward region to take advantage of the pixel tracking coverage extension a new detector, ME0 station, possibly behind the new forward calorimeter. New resistive micro-pattern gaseous detectors that are able to handle the very demanding spatial, time resolution and rate capability, are being considered. In this contribution we introduce a new type of MPGD technology the Fast Timing Micro-pattern (FTM) detector, utilizing a fully resistive WELL structure. It consists of a stack of several coupled layers where drift and WELL multiplication stages alternate in the structure, yielding a significant improvement in timing p...

  19. Modeling in Real Time During the Ebola Response.

    Meltzer, Martin I; Santibanez, Scott; Fischer, Leah S; Merlin, Toby L; Adhikari, Bishwa B; Atkins, Charisma Y; Campbell, Caresse; Fung, Isaac Chun-Hai; Gambhir, Manoj; Gift, Thomas; Greening, Bradford; Gu, Weidong; Jacobson, Evin U; Kahn, Emily B; Carias, Cristina; Nerlander, Lina; Rainisch, Gabriel; Shankar, Manjunath; Wong, Karen; Washington, Michael L

    2016-01-01

    To aid decision-making during CDC's response to the 2014-2016 Ebola virus disease (Ebola) epidemic in West Africa, CDC activated a Modeling Task Force to generate estimates on various topics related to the response in West Africa and the risk for importation of cases into the United States. Analysis of eight Ebola response modeling projects conducted during August 2014-July 2015 provided insight into the types of questions addressed by modeling, the impact of the estimates generated, and the difficulties encountered during the modeling. This time frame was selected to cover the three phases of the West African epidemic curve. Questions posed to the Modeling Task Force changed as the epidemic progressed. Initially, the task force was asked to estimate the number of cases that might occur if no interventions were implemented compared with cases that might occur if interventions were implemented; however, at the peak of the epidemic, the focus shifted to estimating resource needs for Ebola treatment units. Then, as the epidemic decelerated, requests for modeling changed to generating estimates of the potential number of sexually transmitted Ebola cases. Modeling to provide information for decision-making during the CDC Ebola response involved limited data, a short turnaround time, and difficulty communicating the modeling process, including assumptions and interpretation of results. Despite these challenges, modeling yielded estimates and projections that public health officials used to make key decisions regarding response strategy and resources required. The impact of modeling during the Ebola response demonstrates the usefulness of modeling in future responses, particularly in the early stages and when data are scarce. Future modeling can be enhanced by planning ahead for data needs and data sharing, and by open communication among modelers, scientists, and others to ensure that modeling and its limitations are more clearly understood. The activities summarized in

  20. Time orientation, planning horizons and responsibility into the future

    Subjects of four categories (social science students, engineering students, retired people and nuclear waste experts) were asked about past events, planning, risks and future time with emphasis on energy related issues and in particular questions concerning spent nuclear waste. Among, the results reported it was found that events in the past were located more or less correctly and that events further back systematically too close to the present. Today's responsibility into the future was judged to cover 3 to 6 generations ahead and an adequate planning horizon for a local community to be on the average 11 to 14 years. Adequate planning horizons for the handling of spent nuclear fuel were judged to be from 100 to 500 years. The responsibility for effects of today's decisions was judged to be from about 100 to 300 years into the future for environmental pollution and from about 50 to 600 years for nuclear waste. However, non-negliqable proportions of the subjects choose a more moral standpoint and gave answers indicating that responsibility had to be unlimited. Some sex differences were found and an interaction with age offered as a hypothesis to be investigated in the future. Interrelations between clusters of questions revealed some links from past time and planning to judgements of environmental and nuclear power related risks. (orig.)

  1. Fast reactor parameter optimization taking into account changes in fuel charge type during reactor operation time

    The formulation and solution of optimization problem for parameters determining the layout of the central part of sodium cooled power reactor taking into account possible changes in fuel charge type during reactor operation time are performed. The losses under change of fuel composition type for two reactor modifications providing for minimum doubling time for oxide and carbide fuels respectively, are estimated

  2. Performance of SiPMT array readout for fast time-of-flight detectors

    Scintillator based time-of-flight detectors may use conventional photomultipliers for the readout. Problems arise in presence of stray magnetic fields. SiPMT arrays are insensitive to magnetic fields and are a suitable option to replace photomultipliers. Timing performances for several SiPMT arrays have been studied and results are presented

  3. Development of a very fast spectral response measurement system for analysis of hydrogenated amorphous silicon solar cells and modules

    Rodriguez, J.A., E-mail: jose.rodriguez@tsolar.eu [Dept. Technology, Development and Innovation, T-Solar Global S.A., Parque Tecnologico de Galicia, Avda. de Vigo 5, E-32900 San Cibrao das Vinas (Ourense) (Spain); Fortes, M. [Departamento de Electronica e Computacion, Universidade de Santiago de Compostela, 15782 Santiago de Compostela (Spain); Alberte, C.; Vetter, M.; Andreu, J. [Dept. Technology, Development and Innovation, T-Solar Global S.A., Parque Tecnologico de Galicia, Avda. de Vigo 5, E-32900 San Cibrao das Vinas (Ourense) (Spain)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer Spectral response equipment for measuring a-Si:H solar cells in a few seconds. Black-Right-Pointing-Pointer Equipment based on 16 LEDs with simultaneous illumination of the solar cell. Black-Right-Pointing-Pointer The current generated by each LED is analyzed by a Fast Fourier Transform. Black-Right-Pointing-Pointer Cheap equipment without lock-in technology for the current measurement. Black-Right-Pointing-Pointer Measurement error vs. conventional measurement less than 1% in J{sub sc}. - Abstract: An important requirement for a very fast spectral response measurement system is the simultaneous illumination of the solar cell at multiple well defined wavelengths. Nowadays this can be done by means of light emitting diodes (LEDs) available for a multitude of wavelengths. For the purpose to measure the spectral response (SR) of amorphous silicon solar cells a detailed characterization of LEDs emitting in the wavelength range from 300 nm to 800 nm was performed. In the here developed equipment the LED illumination is modulated in the frequency range from 100 Hz to 200 Hz and the current generated by each LED is analyzed by a Fast Fourier Transform (FFT) to determine the current component corresponding to each wavelength. The equipment provides a signal to noise ratio of 2-4 orders of magnitude for individual wavelengths resulting in a precise measurement of the SR over the whole wavelength range. The difference of the short circuit current determined from the SR is less than 1% in comparison to a conventional system with monochromator.

  4. Significance of coast down time on safety and availability of a pool type fast breeder reactor

    Highlights: • Plant dynamics studies for quantifying the benefits of flow coast down time. • Establishment of minimum flow coast down time required for safety. • Assessment of influence of flow coast down on enhancing plant availability. • Synthesis of thermo mechanical benefits of flow coast down time on component design. - Abstract: Plant dynamic investigation towards establishing the influence of flow coast down time of primary and secondary sodium systems on safety and availability of plant has been carried out based on one dimensional analysis. From safety considerations, a minimum flow coast down time for primary sodium circuit is essential to be provided to limit the consequences of loss of flow event within allowable limits. Apart from safety benefits, large primary coast down time also improves plant availability by the elimination of reactor SCRAM during short term power failure events. Threshold values of SCRAM parameters also need optimization. By suitably selecting the threshold values for SCRAM parameters, significant reduction in the inertia of pumping systems can be derived to obtain desirable results on plant availability. With the optimization of threshold values and primary flow coast down behaviour equivalent to a halving time of 8 s, there is a possibility to eliminate reactor SCRAM during short term power failure events extending up to 0.75 s duration. Benefits of secondary flow halving on reducing transient thermal loading on components have also been investigated and mixed effects have been observed

  5. Fast interactive real-time volume rendering of real-time three-dimensional echocardiography: an implementation for low-end computers

    Saracino, G.; Greenberg, N. L.; Shiota, T.; Corsi, C.; Lamberti, C.; Thomas, J. D.

    2002-01-01

    Real-time three-dimensional echocardiography (RT3DE) is an innovative cardiac imaging modality. However, partly due to lack of user-friendly software, RT3DE has not been widely accepted as a clinical tool. The object of this study was to develop and implement a fast and interactive volume renderer of RT3DE datasets designed for a clinical environment where speed and simplicity are not secondary to accuracy. Thirty-six patients (20 regurgitation, 8 normal, 8 cardiomyopathy) were imaged using RT3DE. Using our newly developed software, all 3D data sets were rendered in real-time throughout the cardiac cycle and assessment of cardiac function and pathology was performed for each case. The real-time interactive volume visualization system is user friendly and instantly provides consistent and reliable 3D images without expensive workstations or dedicated hardware. We believe that this novel tool can be used clinically for dynamic visualization of cardiac anatomy.

  6. Fast Numerical Evaluation of Time-Derivative Nonadiabatic Couplings for Mixed Quantum-Classical Methods.

    Ryabinkin, Ilya G; Nagesh, Jayashree; Izmaylov, Artur F

    2015-11-01

    We have developed a numerical differentiation scheme that eliminates evaluation of overlap determinants in calculating the time-derivative nonadiabatic couplings (TDNACs). Evaluation of these determinants was the bottleneck in previous implementations of mixed quantum-classical methods using numerical differentiation of electronic wave functions in the Slater determinant representation. The central idea of our approach is, first, to reduce the analytic time derivatives of Slater determinants to time derivatives of molecular orbitals and then to apply a finite-difference formula. Benchmark calculations prove the efficiency of the proposed scheme showing impressive several-order-of-magnitude speedups of the TDNAC calculation step for midsize molecules. PMID:26538034

  7. Time-dependent response of dissipative electron systems

    We present a systematic study of the influence of energy and phase relaxation on dynamic polarizability simulations in the linear response regime. The nonperturbative approach is based on explicit electron dynamics using short laser pulses of low intensities. To include environmental effects on the property calculation, we use the time-dependent configuration-interaction method in its reduced density matrix formulation. Both energy dissipation and nonlocal pure dephasing are included. The explicit treatment of time-resolved electron dynamics gives access to the phase shift between the electric field and the induced dipole moment, which can be used to define a useful uncertainty measure for the dynamic polarizability. The nonperturbative treatment is compared to perturbation theory expressions, as applied to a simple model system, the rigid H2 molecule. It is shown that both approaches are equivalent for low field intensities, but the time-dependent treatment provides complementary information on the phase of the induced dipole moment, which allows for the definition of an uncertainty associated with the computation of the dynamic polarizability in the linear response regime.

  8. A combined feedforward and feedback control scheme for low-ripple fast-response switchmode magnet power supplies

    In this paper, a new feedforward technique is introduced, and a combined feedforward/feedback control scheme is applied to switchmode magnet power supplies for low-ripple fast-response performance. The purposes of the feedforward technique are two-fold: to reduce the effect of source variations and low-order harmonics, and to improve the reference tracking ability of the system. The algorithm of the proposed control scheme is presented in the paper, and results of a two-quadrant system are provided to verify the concept

  9. Optimized choice of method for determining proliferation response of peripheral lymphocytes to mitogens in low dose irradiation with cyclotron fast neutrons

    Heparinized venous blood sampled from seven donors was irradiated with doses of 0.1; 0.25; 0.5; 1.0; 2.0 and 3.0 Gy of fast neutrons of a mean energy of 7.6 MeV using the U 120 M isochronous cyclotron. A non-irradiated control sample was also prepared. A lymphoblastic transformation test was conducted with both the intact and irradiated samples. The samples were cultivated in the RPMI-1640 medium with and without a mitogen addition, this in five time variants, viz., for 48, 72, 90, 96 and 120 hours. The proliferation was monitored of lymphocytes stimulated with mitogens PHA, CON-A and PWM in dependence on the time of cultivation and on the radiation dose. The dose dependent relative response was also studied of the irradiated lymphocytes. (E.J.). 8 figs., 1 tab., 18 refs

  10. Time-of-flight techniques applied to neutron spectra measurements in fast subcritical assemblies

    Time-of-flight measurements on Uranium-Graphite assemblies were performed using the BCMN linear accelerator. Methods to provide scalar spectra averaged over a core cell from these experimental results are described

  11. Wavelet-based fast time-resolved magnetic sensing with electronic spins in diamond

    Xu, Nanyang; Jiang, Fengjian; Tian, Yu(School of Physics, University of Chinese Academy of Sciences, Beijing, 100049, China); Ye, Jianfeng; Shi, Fazhan; Lv, Haijiang; Wang, Ya; Wrachtrup, Jorg; Du, Jiangfeng

    2015-01-01

    Time-resolved magnetic sensing is of great importance from fundamental studies to applications in physical and biological sciences. Recently the nitrogen-vacancy (NV) defect center in diamond has been developed as a promising sensor of magnetic field under ambient conditions. However the methods to reconstruct time-resolved magnetic field with high sensitivity are not yet fully developed. Here, we propose and demonstrate a novel sensing method based on spin echo, and Haar wavelet transform. O...

  12. Rapid quantification of microRNAs in plasma using a fast real time PCR system

    Andrews, William John; Brown, Eoin Daniel; Dellett, Margaret; Hogg, Ruth Esther; Simpson, David Arthur

    2015-01-01

    The ability to rapidly detect circulating small RNAs, in particular microRNAs (miRNAs), would further increase their already established potential as biomarkers in a range of conditions. One rate-limiting factor is the time taken to perform quantitative real time PCR amplification. We therefore evaluated the ability of a novel thermal cycler to perform this step in less than 10 minutes. Quantitative PCR was performed on an xxpress® thermal cycler (BJS Biotechnologies, Perivale, UK), which emp...

  13. Field Experience with and Potential for Multi-time Scale Grid Transactions from Responsive Commercial Buildings

    Piette, Mary Ann; Kiliccote, Sila; Ghatikar, Girish

    2014-08-01

    The need for and concepts behind demand response are evolving. As the electric system changes with more intermittent renewable electric supply systems, there is a need to allow buildings to provide more flexible demand. This paper presents results from field studies and pilots, as well as engineering estimates of the potential capabilities of fast load responsiveness in commercial buildings. We present a sector wide analysis of flexible loads in commercial buildings, which was conducted to improve resource planning and determine which loads to evaluate in future demonstrations. These systems provide important capabilities for future transactional systems. The field analysis is based on results from California, plus projects in the northwest and east coast. End-uses considered include heating, ventilation, air conditioning and lighting. The timescales of control include day-ahead, as well as day-of, 10-minute ahead and even faster response. This technology can provide DR signals on different times scales to interact with responsive building loads. We describe the latency of the control systems in the building and the round trip communications with the wholesale grid operators.

  14. Adaptive Control of Active Balancing System for a Fast Speed-varying Jeffcott Rotor with Actuator Time Delay

    HU Bing; FANG Zhi-chu

    2008-01-01

    Due to actuator time delay existing in an adaptive control of the active balancing system for a fastspeed-varying Jeffcott rotor, if an unsynchronized control force (correction imbalance) is applied to the system,it may lead to degradation in control efficiency and instability of the control system. In order to avoid theseshortcomings, a simple adaptive controller was designed for a strictly positive real rotor system with actuatortime delay, then a Lyapunov-Krasovskii functional was constructed after an appropriate transform of this sys-tem model, the stability conditions of this adaptive control system with actuator time delay were derived. Afteradding a filter function, the active balancing system for the fast speed-varying Jeffcott rotor with actuator timedelay can easily be converted to a strictly positive real system, and thus it can use the above adaptive controllersatisfying the stability conditions. Finally, numerical simulations show that the adaptive controller proposedworks very well to perform the active balancing for the fast speed-varying Jeffcott rotor with actuator timedelay.

  15. Lipolytic and metabolic response to glucagon in fasting king penguins: phase II vs. phase III.

    Bernard, Servane F; Thil, Marie-Anne; Groscolas, Rene

    2003-02-01

    This study aims to determine how glucagon intervenes in the regulation of fuel metabolism, especially lipolysis, at two stages of a spontaneous long-term fast characterized by marked differences in lipid and protein availability and/or utilization (phases II and III). Changes in the plasma concentration of various metabolites and hormones, and in lipolytic fluxes as determined by continuous infusion of [2-3H]glycerol and [1-14C]palmitate, were examined in vivo in a subantarctic bird (king penguin) before, during, and after a 2-h glucagon infusion. In the two fasting phases, glucagon infusion at a rate of 0.025 microg. kg(-1). min(-1) induced a three- to fourfold increase in the plasma concentration and in the rate of appearance (Ra) of glycerol and nonesterified fatty acids, the percentage of primary reesterification remaining unchanged. Infusion of glucagon also resulted in a progressive elevation of the plasma concentration of glucose and beta-hydroxybutyrate and in a twofold higher insulinemia. These changes were not significantly different between the two phases. The plasma concentrations of triacylglycerols and uric acid were unaffected by glucagon infusion, except for a 40% increase in plasma uric acid in phase II birds. Altogether, these results indicate that glucagon in a long-term fasting bird is highly lipolytic, hyperglycemic, ketogenic, and insulinogenic, these effects, however, being similar in phases II and III. The maintenance of the sensitivity of adipose tissue lipolysis to glucagon could suggest that the major role of the increase in basal glucagonemia observed in phase III is to stimulate gluconeogenesis rather than fatty acid delivery. PMID:12388477

  16. CauseMap: fast inference of causality from complex time series

    M. Cyrus Maher

    2015-03-01

    Full Text Available Background. Establishing health-related causal relationships is a central pursuit in biomedical research. Yet, the interdependent non-linearity of biological systems renders causal dynamics laborious and at times impractical to disentangle. This pursuit is further impeded by the dearth of time series that are sufficiently long to observe and understand recurrent patterns of flux. However, as data generation costs plummet and technologies like wearable devices democratize data collection, we anticipate a coming surge in the availability of biomedically-relevant time series data. Given the life-saving potential of these burgeoning resources, it is critical to invest in the development of open source software tools that are capable of drawing meaningful insight from vast amounts of time series data. Results. Here we present CauseMap, the first open source implementation of convergent cross mapping (CCM, a method for establishing causality from long time series data (≳25 observations. Compared to existing time series methods, CCM has the advantage of being model-free and robust to unmeasured confounding that could otherwise induce spurious associations. CCM builds on Takens’ Theorem, a well-established result from dynamical systems theory that requires only mild assumptions. This theorem allows us to reconstruct high dimensional system dynamics using a time series of only a single variable. These reconstructions can be thought of as shadows of the true causal system. If reconstructed shadows can predict points from opposing time series, we can infer that the corresponding variables are providing views of the same causal system, and so are causally related. Unlike traditional metrics, this test can establish the directionality of causation, even in the presence of feedback loops. Furthermore, since CCM can extract causal relationships from times series of, e.g., a single individual, it may be a valuable tool to personalized medicine. We implement

  17. Fast detection of Noroviruses using a real-time PCR assay and automated sample preparation

    Schmid Michael

    2004-06-01

    Full Text Available Abstract Background Noroviruses (NoV have become one of the most commonly reported causative agents of large outbreaks of non-bacterial acute gastroenteritis worldwide as well as sporadic gastroenteritis in the community. Currently, reverse transcriptase polymerase chain reaction (RT-PCR assays have been implemented in NoV diagnosis, but improvements that simplify and standardize sample preparation, amplification, and detection will be further needed. The combination of automated sample preparation and real-time PCR offers such refinements. Methods We have designed a new real-time RT-PCR assay on the LightCycler (LC with SYBR Green detection and melting curve analysis (Tm to detect NoV RNA in patient stool samples. The performance of the real-time PCR assay was compared with that obtained in parallel with a commercially available enzyme immunoassay (ELISA for antigen detection by testing a panel of 52 stool samples. Additionally, in a collaborative study with the Baden-Wuerttemberg State Health office, Stuttgart (Germany the real-time PCR results were blindly assessed using a previously well-established nested PCR (nPCR as the reference method, since PCR-based techniques are now considered as the "gold standard" for NoV detection in stool specimens. Results Analysis of 52 clinical stool samples by real-time PCR yielded results that were consistent with reference nPCR results, while marked differences between the two PCR-based methods and antigen ELISA were observed. Our results indicate that PCR-based procedures are more sensitive and specific than antigen ELISA for detecting NoV in stool specimens. Conclusions The combination of automated sample preparation and real-time PCR provided reliable diagnostic results in less time than conventional RT-PCR assays. These benefits make it a valuable tool for routine laboratory practice especially in terms of rapid and appropriate outbreak-control measures in health-care facilities and other settings.

  18. A New Characteristic Function for Fast Time-Reverse Seismic Event Location

    Hendriyana, Andri; Bauer, Klaus; Weber, Michael; Jaya, Makky; Muksin, Muksin

    2015-04-01

    Microseismicity produced by natural activities is usually characterized by low signal-to-noise ratio and huge amount of data as recording is conducted for a long period of time. Locating microseismic events is preferably carried out using migration-based methods such as time-reverse modeling (TRM). The original TRM is based on backpropagating the wavefield from the receiver down to the source location. Alternatively, we are using a characteristic function (CF) derived from the measured wavefield as input for the TRM. The motivation for such a strategy is to avoid undesired contributions from secondary arrivals which may generate artifacts in the final images. In this presentation, we introduce a new CF as input for TRM method. To obtain this CF, initially we apply kurtosis-based automatic onset detection and convolution with a given wavelet. The convolution with low frequency wavelets allows us to conduct time-reverse modeling using coarser sampling hence it will reduce computing time. We apply the method to locate seismic events measured along an active part of the Sumatra Fault around the Tarutung pull-apart basin (North Sumatra, Indonesia). The results show that seismic events are well-determined since they are concentrated along the Sumatran fault. Internal details of the Tarutung basin structure could be derived. Our results are consistent with those obtained from inversion of manually picked travel time data.

  19. Fast evaluation of a time-domain non-linear cochlear model on GPUs

    Sabo, Doron; Barzelay, Oded; Weiss, Shlomo; Furst, Miriam

    2014-05-01

    We present a parallel algorithm that solves a time-domain non-linear mathematical model of the cochlea. The previously known serial solution of the cochlear model is based on LU decomposition in the longitudinal dimension and is iterative in the time dimension. These two characteristics of the serial solution limit parallelism and prevent efficient computations on a massively parallel processor. We introduce a novel parallel algorithm that successfully overcomes the challenges posed by the cochlear model. We present performance results of a parallel implementation of the algorithm that shortens the computation time by a typical factor of 160-180, which makes the proposed algorithm of practical value for applications such as clinical audiological diagnosis.

  20. Antiferroelectric Thin-Film Capacitors with High Energy-Storage Densities, Low Energy Losses, and Fast Discharge Times.

    Ahn, Chang Won; Amarsanaa, Gantsooj; Won, Sung Sik; Chae, Song A; Lee, Dae Su; Kim, Ill Won

    2015-12-01

    We demonstrate a capacitor with high energy densities, low energy losses, fast discharge times, and high temperature stabilities, based on Pb(0.97)Y(0.02)[(Zr(0.6)Sn(0.4))(0.925)Ti(0.075)]O3 (PYZST) antiferroelectric thin-films. PYZST thin-films exhibited a high recoverable energy density of U(reco) = 21.0 J/cm(3) with a high energy-storage efficiency of η = 91.9% under an electric field of 1300 kV/cm, providing faster microsecond discharge times than those of commercial polypropylene capacitors. Moreover, PYZST thin-films exhibited high temperature stabilities with regard to their energy-storage properties over temperatures ranging from room temperature to 100 °C and also exhibited strong charge-discharge fatigue endurance up to 1 × 10(7) cycles. PMID:26606502

  1. Fast and Low-Complexity Simulations of the Inquiry Time in Bluetooth

    Figueiras, Joao; Schwefel, Hans-Peter

    2006-01-01

    The timing behavior of the Inquiry Procedure in Bluetooth is relevant for several important functionalities, in particular topology formation and localization. The detailed Inquiry procedure is rather complex and simulation models may become inefficient if they implement the full detailed...... specification. This paper presents an abstracted model to approximate the distribution of Bluetooth inquiry time for scenarios in which multiple Bluetooth nodes perform the inquiry procedure. The abstracted model leads to a simple algorithm which can be used in simulation models to generate samples from...

  2. Toward fast calibration of global drift in scanning electron microscopes with respect to time and magnification.

    Malti, Abed Choaib; Dembélé, Sounkalo; Le Fort-Piat, Nadine; Arnoult, Claire; Marturi, Naresh

    2012-01-01

    It is a well-known fact that scanning electron microscopic (SEM) image acquisition is mainly affected by nonlinearities and instabilities of the column and probe-specimen interaction; in turn, producing a shift in the image points with respect to many parameters and time, in particular. Even though this drift is comparatively less in modern SEMs, it is still an important factor to consider in most of the SEM-based applications. In this airticle, a simple and real-time method is proposed to es...

  3. Response to Selection for Fast Growth in the Second Generation of Pacific Oyster (Crassostrea gigas)

    WANG Qingzhi; LI Qi; KONG Lingfeng; YU Ruihai

    2012-01-01

    Mass selection for fast growth was conducted in three Pacific oyster(Crassostrea gigas)stocks from China,Japan and Korea using previously established lines(CS1,JS 1,and KS 1).To determine whether continuous progress can be achieved by selection for growth,the progeny of three second-generation Pacific oyster lines was selected for shell height and evaluated via a 400-day farming experiment.When harvested at the end of the experiment,the selected crosses of CS2,JS2,and KS2 lines grew by 9.2%,10.2% and 9.6% larger than the control crosses,respectively.During grow-out stage,the genetic gain of three selected lines was (10.2 ± 1.4)%,(10.4 ± 0.3)%,and(8.4 ± 1.6)%,respectively;and the corresponding realized heritability was 0.457 ± 0.143,0.312 ±0.071 and 0.332 ± 0.009,respectively.These results indicated that the selection for fast growth achieved steady progress in the second generation of oyster.Our work provides supportive evidence for the continuity of the Pacific oyster selective breeding program.

  4. Time-resolved photo and radio-luminescence studies demonstrate the possibility of using InGaN/GaN quantum wells as fast scintillators

    In the recent publication by Hospodková et al, the authors investigate III-N quantum well structures as potential fast scintillators (Hospodková et al 2014 Nanotechnology 25 455501). The InGaN/GaN quantum well structures are grown using metal organic vapour phase epitaxy on a sapphire substrate and the fast carrier decay times are characterized by time resolved photo and radioluminescence. (viewpoint)

  5. The effect of alcohol hangover on choice response time.

    Grange, James A; Stephens, Richard; Jones, Kate; Owen, Lauren

    2016-07-01

    The effect of alcohol hangover on cognitive processing has received little attention. We explored the effect of alcohol hangover on choice response time (RT), a dominant dependent variable (DV) in cognitive research. Prior research of the effect of hangover on RT has produced mixed findings; all studies reviewed relied exclusively on estimates of central tendency (e.g. mean RT), which has limited information value. Here we present novel analytical methods by going beyond mean RT analysis. Specifically, we examined performance in hangover conditions (n=31) across the whole RT distribution by fitting ex-Gaussian models to participant data, providing a formal description of the RT distribution. This analysis showed detriments to performance under hangover conditions at the slower end of the RT distribution and increased RT variance under hangover conditions. We also fitted an explicit mathematical process model of choice RT - the diffusion model - which estimates parameters reflecting psychologically-meaningful processes underlying choice RT. This analysis showed that hangover reduced information processing efficiency during response selection, and increased response caution; changes in these parameters reflect hangover affecting core decisional-components of RT performance. The implications of the data as well as the methods used for hangover research are discussed. PMID:27166364

  6. Increased sensitivity of fast BOLD fMRI with a subject-specific hemodynamic response function and application to epilepsy.

    Proulx, Sébastien; Safi-Harb, Mouna; Levan, Pierre; An, Dongmei; Watanabe, Satsuki; Gotman, Jean

    2014-06-01

    Activation detection in functional Magnetic Resonance Imaging (fMRI) typically assumes the hemodynamic response to neuronal activity to be invariant across brain regions and subjects. Reports of substantial variability of the morphology of blood-oxygenation-level-dependent (BOLD) responses are accumulating, suggesting that the use of a single generic model of the expected response in general linear model (GLM) analyses does not provide optimal sensitivity due to model misspecification. Relaxing assumptions of the model can limit the impact of hemodynamic response function (HRF) variability, but at a cost on model parsimony. Alternatively, better specification of the model could be obtained from a priori knowledge of the HRF of a given subject, but the effectiveness of this approach has only been tested on simulation data. Using fast BOLD fMRI, we characterized the variability of hemodynamic responses to a simple event-related auditory-motor task, as well as its effect on activation detection with GLM analyses. We show the variability to be higher between subjects than between regions and variation in different regions to correlate from one subject to the other. Accounting for subject-related variability by deriving subject-specific models from responses to the task in some regions lead to more sensitive detection of responses in other regions. We applied the approach to epilepsy patients, where task-derived patient-specific models provided additional information compared to the use of a generic model for the detection of BOLD responses to epileptiform activity identified on scalp electro-encephalogram (EEG). This work highlights the importance of improving the accuracy of the model for detecting neuronal activation with fMRI, and the fact that it can be done at no cost to model parsimony through the acquisition of independent a priori information about the hemodynamic response. PMID:24582920

  7. Fast and Practical Head Tracking in Brain Imaging with Time-of-Flight Camera

    Wilm, Jakob; Olesen, Oline Vinter; Jensen, Rasmus Ramsbøl; Højgaard, Liselotte; Larsen, Rasmus

    2013-01-01

    This paper investigates the potential use of Time-of-Flight cameras (TOF) for motion correction in medical brain scans. TOF cameras have previously been used for tracking purposes, but recent progress in TOF technology has made it relevant for high speed optical tracking in high resolution medical...

  8. Experts in Fast-Ball Sports Reduce Anticipation Timing Cost by Developing Inhibitory Control

    Nakamoto, Hiroki; Mori, Shiro

    2012-01-01

    The present study was conducted to examine the relationship between expertise in movement correction and rate of movement reprogramming within limited time periods, and to clarify the specific cognitive processes regarding superior reprogramming ability in experts. Event-related potentials (ERPs) were recorded in baseball experts (n = 7) and…

  9. A fast large-area position-sensitive time-of-flight neutron detection system

    A new position-sensitive time-of-flight neutron detection and histograming system has been developed for use at the Intense Pulsed Neutron Source. Spatial resolution of roughly 1 cm x 1 cm and time-of-flight resolution of ∼1 μsec are combined in a detection system which can ultimately be expanded to cover several square meters of active detector area. This system is based on the use of arrays of cylindrical one-dimensional position-sensitive proportional counters, and is capable of collecting the x-y-t data and sorting them into histograms at time-averaged data rates up to ∼300,000 events/sec over the full detector area and with instantaneous data rates up to more than fifty times that. Numerous hardware features have been incorporated to facilitate initial tuning of the position encoding, absolute calibration of the encoded positions, and automatic testing for drifts. 7 refs., 11 figs., 1 tabs

  10. On fast computation of finite-time coherent sets using radial basis functions.

    Froyland, Gary; Junge, Oliver

    2015-08-01

    Finite-time coherent sets inhibit mixing over finite times. The most expensive part of the transfer operator approach to detecting coherent sets is the construction of the operator itself. We present a numerical method based on radial basis function collocation and apply it to a recent transfer operator construction [G. Froyland, "Dynamic isoperimetry and the geometry of Lagrangian coherent structures," Nonlinearity (unpublished); preprint arXiv:1411.7186] that has been designed specifically for purely advective dynamics. The construction [G. Froyland, "Dynamic isoperimetry and the geometry of Lagrangian coherent structures," Nonlinearity (unpublished); preprint arXiv:1411.7186] is based on a "dynamic" Laplace operator and minimises the boundary size of the coherent sets relative to their volume. The main advantage of our new approach is a substantial reduction in the number of Lagrangian trajectories that need to be computed, leading to large speedups in the transfer operator analysis when this computation is costly. PMID:26328580

  11. Research on fast real-time adaptive audio mixing in multimedia conference

    FAN Xing; GU Wei-kang; YE Xiu-qing

    2005-01-01

    In multimedia conference, the capability of audio processing is basic and requires more for real-time criteria. In this article, we categorize and analyze the schemes, and provide several multipoint speech audio mixing schemes using weighted algorithm, which meet the demand of practical needs for real-time multipoint speech mixing, for which the ASW and AEW schemes are especially recommended. Applying the adaptive algorithms, the high-performance schemes we provide do not use the saturation operation widely used in multimedia processing. Therefore, no additional noise will be added to the output. The above adaptive algorithms have relatively low computational complexity and good hearing perceptibility. The schemes are designed for parallel processing, and can be easily implemented with hardware, such as DSPs, and widely applied in multimedia conference systems.

  12. Fast evaluation of far-field signals for time-domain wave propagation

    Field, Scott E

    2014-01-01

    Time-domain simulation of wave phenomena on a finite computational domain often requires a fictitious outer boundary. An important practical issue is the specification of appropriate boundary conditions on this boundary, often conditions of complete transparency. Attention to this issue has been paid elsewhere, and here we consider a different, although related, issue: far-field signal recovery. Namely, from smooth data recorded on the outer boundary we wish to recover the far-field signal which would reach arbitrarily large distances. These signals encode information about interior scatterers and often correspond to actual measurements. This article expresses far-field signal recovery in terms of time-domain convolutions, each between a solution multipole moment recorded at the boundary and a sum-of-exponentials kernel. Each exponential corresponds to a pole term in the Laplace transform of the kernel, a finite sum of simple poles. Greengard, Hagstrom, and Jiang have derived the large-$\\ell$ (spherical-harmo...

  13. The fast algorithm solving the one-dimensional time-dependent Schroedinger equation for teaching purposes

    Computer program aiming at application in quantum mechanics didactics has been proposed. This program can generate the moving pictures of one-dimensional quantum mechanics scattering phenomena. Constructions of this program provide two options. In the first option the wave packet is generated in infinite one-dimensional well which has walls on the borders of graphic window. In the second option the square potential barrier is located in this well and transmission and reflection of wave packet are shown. We have selected a Gaussian wave packet to represent the initial state of the particle. The wave equation is solved numerically by a method discussed in detail. Solutions for the succesive time moments are graphically presented on the monitor screen. In this way observer can watch whole time-development of physical system. Graphically presented results are physically realistic when program parameters satisfy conditions discussed in this paper. (author)

  14. Fast Intrinsic Mode Decomposition of Time Series Data with Sawtooth Transform

    Lu, Louis Yu

    2007-01-01

    A new method is introduced in this paper to find the intrinsic mode function (IMF) components of time series data. This method is faster and more predictable than the Empirical Mode Decomposition (EMD) method devised by the author of Hilbert Huang Transform (HHT). The approach is to transforms the original data function into a piecewise linear sawtooth function (or triangle wave function), then directly constructs the upper envelope by connecting the maxima and construct lower envelope by connecting minima with straight line segments in the sawtooth space, the IMF is calculated as the difference between the sawtooth function and the mean of the upper and lower envelopes. The results found in the sawtooth space are reversely transformed into the original data space as the required IMF and envelopes mean. This decomposition method process the data in one pass to obtain a unique IMF component without the time consuming repetitive sifting process of EMD method. An alternative decomposition method with sawtooth fu...

  15. Time dependence of silica optical properties during the implantation of fast hydrogen ions: Theory

    Barannik, E; Zhurenko, V; Kononenko, S; Kononenko, O

    2015-01-01

    Formation, excitation and passivation of defects by absorbed hydrogen have been extensively reported in the literature. Here we present a basic luminescence-diffusion model to simulate creation and chemical annealing behavior of non-bridging oxygen hole centers in silica by their treatment under a long-time hydrogen implantation. The model is in a good agreement with experimental data and explains the uncommon nonmonotonic time dependence of the non-bridging oxygen hole centers luminescence during the hydrogen implantation. The proposed model establishes the quantitative relation between the intensity dependence of luminescence on its intrinsic diffusivity, hydrogen concentration, defect concentration and cross-section of their creation. Possibilities to estimate these parameters based on the experimental data for the efficiency of silica luminescence are also discussed.

  16. Space - time structure of radiation from a high-power fast-flow CO2 laser

    The space - time structure of radiation from an industrial electric-discharge, flowing CO2 laser is studied experimentally. For the optimal design of the optical and gas-dynamic sections, a total suppression of high-frequency radiation fluctuations and a lowering of the amplitude of low-frequency fluctuations down to 6% - 10% were observed with increasing output power. At the same time, the intensity distribution in the near-field diffraction zone was complicated and unstable. 'Hot' spots and screw wave-front dislocations were observed in the laser-beam cross section. Numerical simulations showed that the properties of the near-field radiation structure are determined by random caustics and phase singularities formed due to the diffraction transformation of the initial wave-front perturbations. (control of laser radiation parameters)

  17. Fast and Scalable IP Address Lookup with Time Complexity of LogmLogm(n

    Abhishant Prakash

    2014-05-01

    Full Text Available Router is a device which is used to route the incoming data packets from the sender to the destination using the IP address of the destination side. Since the router performs the task in the real time so there are millions and millions of the data packets which the router has to process. The main task in the routing process is to find the corresponding port number for a particular IP address entry stored in the router. Since the router performs the searching task for the millions of incoming data packets an efficient searching algorithm is required to be performed on the routing table. In this paper we proposed an efficient searching algorithm for the routing table of the routers. Various algorithms has been performed in this field with the best time complexity of logm(n of the balanced m way search tree and log2log2(n, we in this paper proposed an efficient searching algorithm with the time complexity of logmlogm(n in the worst case applicable to both the IPV4 and IPV6.

  18. A Fast Ambient Occlusion Method for Real-Time Plant Rendering

    Jun Teng; Marc Jaeger; Bao-Gang HU

    2007-01-01

    Global illumination effects are crucial for virtual plant rendering. Whereas real-time global illumination rendering of plants is impractical, ambient occlusion is an efficient alternative approximation. A tree model with millions of triangles is common, and the triangles can be considered as randomly distributed. The existing ambient occlusion methods fail to apply on such a type of object. In this paper, we present a new ambient occlusion method dedicated to real time plant rendering with limited user interaction. This method is a three-step ambient occlusion calculation framework which is suitable for a huge number of geometry objects distributed randomly in space. The complexity of the proposed algorithm is O(n), compared to the conventional methods with complexities of O(n2). Furthermore, parameters in this method can be easily adjusted to achieve flexible ambient occlusion effects. With this ambient occlusion calculation method, we can manipulate plant models with millions of organs, as well as geometry objects with large number of randomly distributed components with affordable time, and with perceptual quality comparable to the previous ambient occlusion methods.

  19. A fast 1-D detector for imaging and time resolved SAXS experiments

    Menk, R. H.; Arfelli, F.; Bernstorff, S.; Pontoni, D.; Sarvestani, A.; Besch, H. J.; Walenta, A. H.

    1999-02-01

    A one-dimensional test detector on the principle of a highly segmented ionization chamber with shielding grid (Frisch grid) was developed to evaluate if this kind of detector is suitable for advanced small-angle X-ray scattering (SAXS) experiments. At present it consists of 128 pixels which can be read out within 0.2 ms with a noise floor of 2000 e-ENC. A quantum efficiency of 80% for a photon energy of 8 keV was achieved. This leads to DQE values of 80% for photon fluxes above 1000 photons/pixel and integration time. The shielding grid is based on the principles of the recently invented MCAT structure and the GEM structure which also allows electron amplification in the gas. In the case of the MCAT structure, an energy resolution of 20% at 5.9 keV was observed. The gas amplification mode enables imaging with this integrating detector on a subphoton noise level with respect to the integration time. Preliminary experiments of saturation behavior show that this kind of detector digests a photon flux density up to 10 12 photons/mm 2 s and operates linearly. A spatial resolution of at least three line pairs/mm was obtained. All these features show that this type of detector is well suited for time-resolved SAXS experiments as well as high flux imaging applications.

  20. A fast 1-D detector for imaging and time resolved SAXS experiments

    A one-dimensional test detector on the principle of a highly segmented ionization chamber with shielding grid (Frisch grid) was developed to evaluate if this kind of detector is suitable for advanced small-angle X-ray scattering (SAXS) experiments. At present it consists of 128 pixels which can be read out within 0.2 ms with a noise floor of 2000 e-ENC. A quantum efficiency of 80% for a photon energy of 8 keV was achieved. This leads to DQE values of 80% for photon fluxes above 1000 photons/pixel and integration time. The shielding grid is based on the principles of the recently invented MCAT structure and the GEM structure which also allows electron amplification in the gas. In the case of the MCAT structure, an energy resolution of 20% at 5.9 keV was observed. The gas amplification mode enables imaging with this integrating detector on a subphoton noise level with respect to the integration time. Preliminary experiments of saturation behavior show that this kind of detector digests a photon flux density up to 1012 photons/mm2 s and operates linearly. A spatial resolution of at least three line pairs/mm was obtained. All these features show that this type of detector is well suited for time-resolved SAXS experiments as well as high flux imaging applications

  1. Analysis of UAS DAA Surveillance in Fast-Time Simulations without DAA Mitigation

    Thipphavong, David P.; Santiago, Confesor; Isaacson, David R.; Lee, Seung Man; Refai, Mohamad Said; Snow, James William

    2015-01-01

    Realization of the expected proliferation of Unmanned Aircraft System (UAS) operations in the National Airspace System (NAS) depends on the development and validation of performance standards for UAS Detect and Avoid (DAA) Systems. The RTCA Special Committee 228 is charged with leading the development of draft Minimum Operational Performance Standards (MOPS) for UAS DAA Systems. NASA, as a participating member of RTCA SC-228 is committed to supporting the development and validation of draft requirements for DAA surveillance system performance. A recent study conducted using NASA's ACES (Airspace Concept Evaluation System) simulation capability begins to address questions surrounding the development of draft MOPS for DAA surveillance systems. ACES simulations were conducted to study the performance of sensor systems proposed by the SC-228 DAA Surveillance sub-group. Analysis included but was not limited to: 1) number of intruders (both IFR and VFR) detected by all sensors as a function of UAS flight time, 2) number of intruders (both IFR and VFR) detected by radar alone as a function of UAS flight time, and 3) number of VFR intruders detected by all sensors as a function of UAS flight time. The results will be used by SC-228 to inform decisions about the surveillance standards of UAS DAA systems and future requirements development and validation efforts.

  2. Ultra fast miniaturized real-time PCR: 40 cycles in less than six minutes.

    Neuzil, Pavel; Zhang, Chunyan; Pipper, Juergen; Oh, Sharon; Zhuo, Lang

    2006-01-01

    We have designed, fabricated and tested a real-time PCR chip capable of conducting one thermal cycle in 8.5 s. This corresponds to 40 cycles of PCR in 5 min and 40 s. The PCR system was made of silicon micromachined into the shape of a cantilever terminated with a disc. The thin film heater and a temperature sensor were placed on the disc perimeter. Due to the system's thermal constant of 0.27 s, we have achieved a heating rate of 175 degrees C s(-1) and a cooling rate of -125 degrees C s(-1). A PCR sample encapsulated with mineral oil was dispensed onto a glass cover slip placed on the silicon disc. The PCR cycle time was then determined by heat transfer through the glass, which took only 0.5 s. A real-time PCR sample with a volume of 100 nl was tested using a FAM probe. As the single PCR device occupied an area of only a few square millimeters, devices could be combined into a parallel system to increase throughput. PMID:16807313

  3. Fast-timing study of the l -forbidden 1 /2+→3 /2+ M 1 transition in 129Sn

    Licǎ, R.; Mach, H.; Fraile, L. M.; Gargano, A.; Borge, M. J. G.; Mǎrginean, N.; Sotty, C. O.; Vedia, V.; Andreyev, A. N.; Benzoni, G.; Bomans, P.; Borcea, R.; Coraggio, L.; Costache, C.; De Witte, H.; Flavigny, F.; Fynbo, H.; Gaffney, L. P.; Greenlees, P. T.; Harkness-Brennan, L. J.; Huyse, M.; Ibáñez, P.; Judson, D. S.; Konki, J.; Korgul, A.; Kröll, T.; Kurcewicz, J.; Lalkovski, S.; Lazarus, I.; Lund, M. V.; Madurga, M.; Mǎrginean, R.; Marroquín, I.; Mihai, C.; Mihai, R. E.; Morales, A. I.; Nácher, E.; Negret, A.; Page, R. D.; Pakarinen, J.; Pascu, S.; Paziy, V.; Perea, A.; Pérez-Liva, M.; Picado, E.; Pucknell, V.; Rapisarda, E.; Rahkila, P.; Rotaru, F.; Swartz, J. A.; Tengblad, O.; Van Duppen, P.; Vidal, M.; Wadsworth, R.; Walters, W. B.; Warr, N.; IDS Collaboration

    2016-04-01

    The levels in 129Sn populated from the β- decay of 129In isomers were investigated at the ISOLDE facility of CERN using the newly commissioned ISOLDE Decay Station (IDS). The lowest 1 /2+ state and the 3 /2+ ground state in 129Sn are expected to have configurations dominated by the neutron s1 /2 (l =0 ) and d3 /2 (l =2 ) single-particle states, respectively. Consequently, these states should be connected by a somewhat slow l -forbidden M 1 transition. Using fast-timing spectroscopy we have measured the half-life of the 1 /2+ 315.3-keV state, T1 /2= 19(10) ps, which corresponds to a moderately fast M 1 transition. Shell-model calculations using the CD-Bonn effective interaction, with standard effective charges and g factors, predict a 4-ns half-life for this level. We can reconcile the shell-model calculations to the measured T1 /2 value by the renormalization of the M 1 effective operator for neutron holes.

  4. A critical role of fatty acid binding protein 4 and 5 (FABP4/5 in the systemic response to fasting.

    Mas Rizky A A Syamsunarno

    Full Text Available During prolonged fasting, fatty acid (FA released from adipose tissue is a major energy source for peripheral tissues, including the heart, skeletal muscle and liver. We recently showed that FA binding protein 4 (FABP4 and FABP5, which are abundantly expressed in adipocytes and macrophages, are prominently expressed in capillary endothelial cells in the heart and skeletal muscle. In addition, mice deficient for both FABP4 and FABP5 (FABP4/5 DKO mice exhibited defective uptake of FA with compensatory up-regulation of glucose consumption in these tissues during fasting. Here we showed that deletion of FABP4/5 resulted in a marked perturbation of metabolism in response to prolonged fasting, including hyperketotic hypoglycemia and hepatic steatosis. Blood glucose levels were reduced, whereas the levels of non-esterified FA (NEFA and ketone bodies were markedly increased during fasting. In addition, the uptake of the (125I-BMIPP FA analogue in the DKO livers was markedly increased after fasting. Consistent with an increased influx of NEFA into the liver, DKO mice showed marked hepatic steatosis after a 48-hr fast. Although gluconeogenesis was observed shortly after fasting, the substrates for gluconeogenesis were reduced during prolonged fasting, resulting in insufficient gluconeogenesis and enhanced hypoglycemia. These metabolic responses to prolonged fasting in DKO mice were readily reversed by re-feeding. Taken together, these data strongly suggested that a maladaptive response to fasting in DKO mice occurred as a result of an increased influx of NEFA into the liver and pronounced hypoglycemia. Together with our previous study, the metabolic consequence found in the present study is likely to be attributed to an impairment of FA uptake in the heart and skeletal muscle. Thus, our data provided evidence that peripheral uptake of FA via capillary endothelial FABP4/5 is crucial for systemic metabolism and may establish FABP4/5 as potentially novel

  5. The effect of age and microstructural white matter integrity on lap time variation and fast-paced walking speed.

    Tian, Qu; Ferrucci, Luigi; Resnick, Susan M; Simonsick, Eleanor M; Shardell, Michelle D; Landman, Bennett A; Venkatraman, Vijay K; Gonzalez, Christopher E; Studenski, Stephanie A

    2016-09-01

    Macrostructural white matter damage (WMD) is associated with less uniform and slower walking in older adults. The effect of age and subclinical microstructural WM degeneration (a potentially earlier phase of WM ischemic damage) on walking patterns and speed is less clear. This study examines the effect of age on the associations of regional microstructural WM integrity with walking variability and speed, independent of macrostructural WMD. This study involved 493 participants (n = 51 young; n = 209 young-old; n = 233 old-old) from the Baltimore Longitudinal Study of Aging. All completed a 400-meter walk test and underwent a concurrent brain MRI with diffusion tensor imaging. Microstructural WM integrity was measured as fractional anisotropy (FA). Walking variability was measured as trend-adjusted variation in time over ten 40-meter laps (lap time variation, LTV). Fast-paced walking speed was assessed as mean lap time (MLT). Multiple linear regression models of FA predicting LTV and MLT were adjusted for age, sex, height, weight, and WM hyperintensities. Independent of WM hyperintensities, lower FA in the body of the corpus callosum was associated with higher LTV and longer MLT only in the young-old. Lower FA in superior longitudinal, inferior fronto-occipital, and uncinate fasciculi, the anterior limb of the internal capsule, and the anterior corona radiate was associated with longer MLT only in the young-old. While macrostructural WMD is known to predict more variable and slower walking in older adults, microstructural WM disruption is independently associated with more variable and slower fast-paced walking only in the young-old. Disrupted regional WM integrity may be a subclinical contributor to abnormal walking at an earlier phase of aging. PMID:26399234

  6. Time-Resolved Visualization of Görtler Vortices in a Pulsed Convex Wall Jet using Fast Pressure-Sensitive Paint

    Gregory, James; Danon, Ron; Greenblatt, David

    2015-11-01

    The time-resolved formation and structure of Görtler vortices in a pulsed convex wall jet are studied in this work. While the presence of Görtler vortices in laminar boundary layers on concave surfaces can be clearly observed, their presence in wall jets flowing over convex surfaces is difficult to discern due to transition to turbulence in the outer part of the jet. This work employed fast-response pressure-sensitive paint (PSP), which has a documented flat frequency response greater than 5 kHz, to visualize the time-resolved formation of the wall jet and the details of the Görtler vortices. The radius of curvature of the wall jet was 8 cm, and the Reynolds number (based on slot height and jet exit velocity) was varied between 5 ×102 and 4 ×104 . The characteristic spanwise wavelength of the vortices was studied as a function of jet Reynolds number. Furthermore, as the Reynolds number was increased, various secondary instabilities were observed that led to laminar-turbulent transition. Funding provided by the U.S. Fulbright Scholar Program.

  7. Establishment of threshold values for bioeffects of magnetic fields with fast time variability

    Magnetic resonance imaging (MRI) offers images with outstanding tissue contrast for clinical diagnosis without any exposure to radiation for the patient. To fasten MRI switching times of magnetic gradient fields were shortened in recent years. Thus, currents in the body of a patient are induced capable of causing a stimulation of peripheral nerves. A stimulation of peripheral nerves in magnetic resonance imaging (MRI) was proved by means of electromyography (EMG) in a magnetic resonance imager. A wide variety of stimulation thresholds among the subjects was found. The report of subjects about a stimulation was compared with the evaluation of EMG. It could be shown, that the wide variety of stimulation thresholds among the subjects is a fact and not due to the subjective perception levels of different subjects. Different models of electrical stimulation were successfully applied to rate the stimulation by switched magnetic gradient fields in MRI. The neurophysiologic parameters chronaxie and rheobase describing the stimulation properties of different excitable tissues were determined in a stimulation experiment in MRI. A comprehensive model was established that is capable of predicting the stimulation of individual subjects undergoing arbitrary gradient time courses in MRI. Exchanging the neurophysiologic parameters in the model with the parameters of the heart, the stimulation thresholds of dog hearts determined in an experiment of another working group could be reproduced. The dependence of stimulation thresholds on constitutional parameters of the subjects and on the position of the subjects in the MR imager was investigated and significant correlation was found. A stimulation of peripheral nerves takes place, if the maximum magnetic flux density of a gradient coincides with a body area, where a large conducting loop can be formed and if sections of the conducting loop are parallel to structures of peripheral nerves (so called dermatoms). An appraisal of

  8. Insertable system for fast turnaround time microwave experiments in a dilution refrigerator

    Ong, Florian R.; Orgiazzi, Jean-Luc; de Waard, Arlette; Frossati, Giorgio; Lupascu, Adrian

    2012-01-01

    Microwave experiments in dilution refrigerators are a central tool in the field of superconducting quantum circuits and other research areas. This type of experiments relied so far on attaching a device to the mixing chamber of a dilution refrigerator. The minimum turnaround time in this case is a few days as required by cooling down and warming up the entire refrigerator. We developed a new approach, in which a suitable sample holder is attached to a cold-insertable probe and brought in cont...

  9. A Modified Fast Approximated Power Iteration Subspace Tracking Method for Space-Time Adaptive Processing

    Yang Zhiwei

    2010-01-01

    Full Text Available We propose a subspace-tracking-based space-time adaptive processing technique for airborne radar applications. By applying a modified approximated power iteration subspace tracing algorithm, the principal subspace in which the clutter-plus-interference reside is estimated. Therefore, the moving targets are detected by projecting the data on the minor subspace which is orthogonal to the principal subspace. The proposed approach overcomes the shortcomings of the existing methods and has satisfactory performance. Simulation results confirm that the performance improvement is achieved at very small secondary sample support, a feature that is particularly attractive for applications in heterogeneous environments.

  10. Ultra fast miniaturized real-time PCR: 40 cycles in less than six minutes

    Neuzil, Pavel; Zhang, Chunyan; Pipper, Juergen; Oh, Sharon; Zhuo, Lang

    2006-01-01

    We have designed, fabricated and tested a real-time PCR chip capable of conducting one thermal cycle in 8.5 s. This corresponds to 40 cycles of PCR in 5 min and 40 s. The PCR system was made of silicon micromachined into the shape of a cantilever terminated with a disc. The thin film heater and a temperature sensor were placed on the disc perimeter. Due to the system's thermal constant of 0.27 s, we have achieved a heating rate of 175°C s−1 and a cooling rate of −125°C s−1. A PCR sample encap...

  11. Fast and robust optical flow for time-lapse microscopy using super-voxels

    Amat, Fernando; Myers, Eugene W.; Keller, Philipp J.

    2012-01-01

    Motivation: Optical flow is a key method used for quantitative motion estimation of biological structures in light microscopy. It has also been used as a key module in segmentation and tracking systems and is considered a mature technology in the field of computer vision. However, most of the research focused on 2D natural images, which are small in size and rich in edges and texture information. In contrast, 3D time-lapse recordings of biological specimens comprise up to several terabytes of...

  12. Fast solution of Cahn–Hilliard variational inequalities using implicit time discretization and finite elements

    Bosch, Jessica

    2014-04-01

    We consider the efficient solution of the Cahn-Hilliard variational inequality using an implicit time discretization, which is formulated as an optimal control problem with pointwise constraints on the control. By applying a semi-smooth Newton method combined with a Moreau-Yosida regularization technique for handling the control constraints we show superlinear convergence in function space. At the heart of this method lies the solution of large and sparse linear systems for which we propose the use of preconditioned Krylov subspace solvers using an effective Schur complement approximation. Numerical results illustrate the competitiveness of this approach. © 2014 Elsevier Inc.

  13. Driving time modulates accommodative response and intraocular pressure.

    Vera, Jesús; Diaz-Piedra, Carolina; Jiménez, Raimundo; Morales, José M; Catena, Andrés; Cardenas, David; Di Stasi, Leandro L

    2016-10-01

    Driving is a task mainly reliant on the visual system. Most of the time, while driving, our eyes are constantly focusing and refocusing between the road and the dashboard or near and far traffic. Thus, prolonged driving time should produce visual fatigue. Here, for the first time, we investigated the effects of driving time, a common inducer of driver fatigue, on two ocular parameters: the accommodative response (AR) and the intraocular pressure (IOP). A pre/post-test design has been used to assess the impact of driving time on both indices. Twelve participants (out of 17 recruited) completed the study (5 women, 24.42±2.84years old). The participants were healthy and active drivers with no visual impairment or pathology. They drove for 2h in a virtual driving environment. We assessed AR and IOP before and after the driving session, and also collected subjective measures of arousal and fatigue. We found that IOP and AR decreased (i.e., the accommodative lag increased) after the driving session (p=0.03 and p<0.001, respectively). Moreover, the nearest distances tested (20cm, 25cm, and 33cm) induced the highest decreases in AR (corrected p-values<0.05). Consistent with these findings, the subjective levels of arousal decreased and levels of fatigue increased after the driving session (all p-values<0.001). These results represent an innovative step towards an objective, valid, and reliable assessment of fatigue-impaired driving based on visual fatigue signs. PMID:27235337

  14. Energetic cost of hovering flight in a nectar-feeding bat measured with fast-response respirometry.

    Winter, Y

    1998-08-01

    Hover-feeding glossophagine bats provide, in addition to the hummingbirds, a second vertebrate model for the analysis of hovering flight based on metabolic measurement and aerodynamic theory. In this study, the power input of hovering Glossophaga soricina bats (11.9 g) was measured by standard respirometry and fast-response (Bats needed 5-7 s after a rest-to-flight transition to return to a respiratory steady state. Therefore, only hovering events preceeded by a 7-s flight interval were evaluated. VO2 during hovering fluctuated with a frequency of 3-5 Hz, which corresponded in frequency to the licking movement of the tongue. During hovering, bats often may have hypoventilated as indicated by reduced VO2 and a respiratory exchange ratio (RER) well below the steady-state value of 1. Steady-state oxygen consumption (and derived power input) during hovering was estimated to be 27 (25-29) ml O2 g-1 h-1 (158 W kg-1 or 1.88 W) in the 11.9-g bats as indicated by three independent findings: (1) VO2 was 26 ml O2 g-1 h-1 after 6.5 s of hovering, (2) the mean RER during single hovering events was at its steady-state level of 1 only at oxygen uptake rates of 25-29 ml g-1 h-1, and (3) when the oxygen potentially released from estimated oxygen stores was added to the measured oxygen uptake, the upper limit for oxygen consumption during hovering was found to be 29 ml O2 g-1 h-1. Hovering power input was about 1.2 times the value of minimum flight power input (Winter and von Helversen 1998) and thus well below the 1.7-2.6 difference in power output postulated by aerodynamic theory (Norberg et al. 1993). Mass specific power input was 40% less than in hummingbirds. Thus, within the possible modes of hovering flight, Glossophaga bats seem to operate at the high-efficiency end of the spectrum. PMID:9747523

  15. Scurvy in the present times: vitamin C allergy leading to strict fast food diet.

    Shaath, Tarek; Fischer, Ryan; Goeser, Megan; Rajpara, Anand; Aires, Daniel

    2016-01-01

    Scurvy results from a deficiency of vitamin C, a nutrient otherwise known as ascorbic acid. Today, scurvy is rare yet emerges in select patients. The patient reported herein developed scurvy secondary to deliberate avoidance of vitamin C-rich foods. Classic cutaneous manifestations of scurvy include follicular hyperkeratosis and perifollicular hemorrhage encompassing coiled "corkscrew" hairs and hairs bent into "swan-neck" deformities. Ecchymoses, purpura, and petechiae are also characteristically prominent. Classic oral abnormalities include erythematous, swollen gingivae that hemorrhage from subtle microtrauma.Subungual linear splinter hemorrhages may also manifest as a sign of the disease. To establish the diagnosis requirements include characteristic physical exam findings, evidence of inadequate dietary intake, and rapid reversal of symptoms upon supplementation. Although unnecessary for diagnosis, histological findings demonstrate perifollicular inflammation and hemorrhage, fibrosis, and hyperkeratosis, amongst dilated hair follicles and keratin plugging. Although citrus fruit allergies have been historically documented, ascorbic acid has not been previously reported as an allergen. Although lacking absolute certainty, this report suggests a presumed case of ascorbic acid allergy based on patient history and favorable response to ascorbic acid desensitization therapy. PMID:26990475

  16. Insertable system for fast turnaround time microwave experiments in a dilution refrigerator.

    Ong, Florian R; Orgiazzi, Jean-Luc; de Waard, Arlette; Frossati, Giorgio; Lupascu, Adrian

    2012-09-01

    Microwave experiments in dilution refrigerators are a central tool in the field of superconducting quantum circuits and other research areas. This type of experiments relied so far on attaching a device to the mixing chamber of a dilution refrigerator. The minimum turnaround time in this case is a few days as required by cooling down and warming up the entire refrigerator. We developed a new approach, in which a suitable sample holder is attached to a cold-insertable probe and brought in contact with transmission lines permanently mounted inside the cryostat. The total turnaround time is 8 h if the target temperature is 80 mK. The lowest attainable temperature is 30 mK. Our system can accommodate up to six transmission lines, with a measurement bandwidth tested from zero frequency to 12 GHz. This bandwidth is limited by low-pass components in the setup; we expect the intrinsic bandwidth to be at least 18 GHz. We present our setup, discuss the experimental procedure, and give examples of experiments enabled by this system. This new measurement method will have a major impact on systematic ultra-low temperature studies using microwave signals, including those requiring quantum coherence. PMID:23020391

  17. R and D on a Fast LXe TPC with real-time event reconstruction

    Dussoni, S., E-mail: simeone.dussoni@pi.infn.it [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Baldini, A. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Galli, L. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Paul Scherrer Institute PSI, CH-5232 Villigen (Switzerland); Cerri, C.; Grassi, M. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Papa, A. [Paul Scherrer Institute PSI, CH-5232 Villigen (Switzerland); Signorelli, G. [INFN Sezione di Pisa, Largo B. Pontecorvo 3, 56127 Pisa (Italy)

    2013-12-21

    The FOXFIRE project (Feasibility Of a Xenon detector with Front-end for Ionization Real-time Extraction) aims at the realization of a Liquid Xenon TPC optimized for high rate particle physics experiments, in particular in the field of rare event searches, with particles in the 10–100 MeV energy range. Liquid Xenon has several attractive properties to be exploited resulting in superior time and energy resolution, by using the scintillation light readout with suitable photo-detectors. A novel approach with a complementary TPC readout scheme can improve the space resolution to a level of a few hundred microns. We are studying both the feasibility of a light readout with higher granularity by means of Silicon PhotoMultipliers optimized for the Xenon emission spectrum as well as on an innovative micro-fabricated device capable of charge multiplication in liquid phase. The detector will be equipped with a readout electronics capable of online reconstruction of events, allowing the detector to sustain a high rate of interactions.

  18. High rate, fast timing Glass RPC for the high ${\\eta}$ CMS muon detectors

    Lagarde, F; Laktineh, I; Buridon, V; Chen, X; Combaret, C; Eynard, A; Germani, L; Grenier, G; Mathez, H; Mirabito, L; Petrukhin, A; Steen, A; Tromeuraa, W; Wang, Y; Gongab, A; Moreau, N; de la Taille, C; Dulucqac, F; Cimmino, A; Crucy, S; Fagot, A; Gul, M; Rios, A A O; Tytgat, M; Zaganidisb, N; Aly, S; Assran, Y; Radi, A; Sayedc, A; Singhd, G; Abbrescia, M; Iaselli, G; Maggi, M; Pugliese, G; Verwilligene, P; f, W Van Doninck; Colafranceschi, S; Sharmag, A; Benussi, L; Bianco, S; Piccolo, D; Primaverah, F; Bhatnagar, V; Kumari, R; Mehta, A; Singhi, J; Ahmad, A; Ahmed, W; Asghar, M I; Awan, I M; Hoorani, R; Muhammad, S; Shahzad, H; j, M A Shah; Cho, S W; Choi, S Y; Hong, B; Kang, M H; Lee, K S; Lim, J H; Parkk, S K; Kiml, M S; Bernardino, S Carpinteyro; Pedraza, I; Estradam, C Uribe; Moreno, S Carrillo; Valencian, F Vazquez; Panto, L M; Buontempo, S; Cavallo, N; Esposito, M; Fabozzi, F; Lanza, G; Orso, I; Lista, L; Meola, S; Merola, M; Paolucci, P; p, F Thyssen; Braghieri, A; Magnani, A; Montagna, P; Riccardi, C; Salvini, P; Vai, I; Vituloq, P; Ban, Y; Qianr, S J; s, M Choi; Choi, Y; Goh, J; Kimt, D; Aleksandrov, A; Hadjiiska, R; Iaydjiev, P; Rodozov, M; Stoykova, S; Sultanov, G; Vutovau, M; Dimitrov, A; Litov, L; Pavlov, B; Petkovv, P; Bagaturia, I; Lomidzew, D; Avila, C; Cabrera, A; Sanabria, J C; Crottyy, I; Vaitkusz, J

    2016-01-01

    The HL-LHC phase is designed to increase by an order of magnitude the amount of data to be collected by the LHC experiments. To achieve this goal in a reasonable time scale the instantaneous luminosity would also increase by an order of magnitude up to $6.10^{34} cm^{-2} s^{-1}$ . The region of the forward muon spectrometer ($|{\\eta}| > 1.6$) is not equipped with RPC stations. The increase of the expected particles rate up to $2 kHz/cm^{2}$ (including a safety factor 3) motivates the installation of RPC chambers to guarantee redundancy with the CSC chambers already present. The actual RPC technology of CMS cannot sustain the expected background level. The new technology that will be chosen should have a high rate capability and provides a good spatial and timing resolution. A new generation of Glass-RPC (GRPC) using low-resistivity (LR) glass is proposed to equip at least the two most far away of the four high ${\\eta}$ muon stations of CMS. First the design of small size prototypes and studies of their perfor...

  19. Ranque-Hilsch vortex tube thermocycler for fast DNA amplification and real-time optical detection

    Ebmeier, Ryan J.; Whitney, Scott E.; Sarkar, Amitabha; Nelson, Michael; Padhye, Nisha V.; Gogos, George; Viljoen, Hendrik J.

    2004-12-01

    An innovative polymerase chain reaction (PCR) thermocycler capable of performing real-time optical detection is described below. This device utilizes the Ranque-Hilsch vortex tube in a system to efficiently and rapidly cycle three 20 μL samples between the denaturation, annealing, and elongation temperatures. The reaction progress is displayed real-time by measuring the size of a fluorescent signal emitted by SYBR green/double-stranded DNA complexes. This device can produce significant reaction yields with very small amounts of initial DNA, for example, it can amplify 0.25 fg (˜5 copies) of a 96 bp bacteriophage λ-DNA fragment 2.7×1011-fold by performing 45 cycles in less than 12 min. The optical threshold (150% of the baseline intensity) was passed 8 min into the reaction at cycle 34. Besides direct applications, the speed and sensitivity of this device enables it to be used as a scientific instrument for basic studies such as PCR assembly and polymerase kinetics.

  20. Ultra fast timing MMRPC: a versatile detector for basic and applied science

    Three decades ago the Resistive Plate Chamber (RPC) was invented to overcome several problems of parallel plate chambers. Unlike parallel plate chambers, electrodes of RPCs are made of resistive material like Bakelite or float glass. This has the effect that only a limited part of the electrode is discharged during the passage of an ionizing particle with subsequent avalanches or streamers, while the rest of the electrode remains unchanged. Wide and/or single gap RPC detectors are used in many large scale experiments to explore various directions of science. This includes fundamental research in particle physics, in astrophysics, in cosmology etc,. In India, RPC detectors array (INO) will play a vital role in the measurement of mass hierarchy of three flavors of neutrino mass. To improve timing resolution, Multigap Resistive Plate Chamber (MRPC) is an intelligent modification of an RPC by increasing the electric field across the gap and creating thinner layers of gas gap by inserting (electrostatically) floating glasses between anode and cathode. It can be shown that a resolution in the range of 50-100 ps is achievable with gaps of 200-300 mm. Moreover, RPCs are insensitive to the magnetic field. Finally timing RPCs have already proved in the last years to be a reliable and stable detector with sensitive larger and regularly used in a large number of experiments