Thermal Noise Canceling in LNAs : A Review

NARCIS (Netherlands)

Nauta, Bram; Klumperink, Eric A.M.; Bruccoleri, Frederico

2004-01-01

Most wide-band amplifiers suffer from a fundamental trade-off between noise figure NF and source impedance matching, which limits NF to values typically above 3dB. Recently, a feed-forward noise canceling technique has been proposed to break this trade-off. This paper reviews the principle of the

Amplifiers Exploiting Thermal Noise Canceling: A Review

NARCIS (Netherlands)

Klumperink, Eric A.M.; Bruccoleri, F.; Stroet, P.M.; Stroet, Peter; Nauta, Bram

2004-01-01

Wide-band LNAs suffer from a fundamental trade-off between noise figure NF and source impedance matching, which limits NF to values typically above 3dB. Recently, a feed-forward noise canceling technique has been proposed to break this trade-off. This paper reviews the principle of the technique and

A computer simulation of an adaptive noise canceler with a single input

Science.gov (United States)

Albert, Stuart D.

1991-06-01

A description of an adaptive noise canceler using Widrows' LMS algorithm is presented. A computer simulation of canceler performance (adaptive convergence time and frequency transfer function) was written for use as a design tool. The simulations, assumptions, and input parameters are described in detail. The simulation is used in a design example to predict the performance of an adaptive noise canceler in the simultaneous presence of both strong and weak narrow-band signals (a cosited frequency hopping radio scenario). On the basis of the simulation results, it is concluded that the simulation is suitable for use as an adaptive noise canceler design tool; i.e., it can be used to evaluate the effect of design parameter changes on canceler performance.

Multi-Stage Adaptive Noise Cancellation Technique for Synthetic Hard-α Inclusion

International Nuclear Information System (INIS)

Kim, Jae Joon

2003-01-01

Adaptive noise cancellation techniques are ideally suitable for reducing spatially varying noise due to the grain structure of material in ultrasonic nondestructive evaluation. Grain noises have an un-correlation property, while flaw echoes are correlated. Thus, adaptive filtering algorithms use the correlation properties of signals to enhance the signal-to-noise ratio (SNR) of the output signal. In this paper, a multi-stage adaptive noise cancellation (MANC) method using adaptive least mean square error (LMSE) filter for enhancing flaw detection in ultrasonic signals is proposed

Active Control of Fan Noise: Feasibility Study. Volume 3; Active Fan Noise Cancellation in the NASA Lewis Active Noise Control Fan Facility

Science.gov (United States)

Pla, Frederic G.; Hu, Ziqiang; Sutliff, Daniel L.

1996-01-01

This report describes the Active Noise Cancellation (ANC) System designed by General Electric and tested in the NASA Lewis Research Center's (LERC) 48 inch Active Noise Control Fan (ANCF). The goal of this study is to assess the feasibility of using wall mounted secondary acoustic sources and sensors within the duct of a high bypass turbofan aircraft engine for global active noise cancellation of fan tones. The GE ANC system is based on a modal control approach. A known acoustic mode propagating in the fan duct is canceled using an array of flush-mounted compact sound sources. The canceling modal signal is generated by a modal controller. Inputs to the controller are signals from a shaft encoder and from a microphone array which senses the residual acoustic mode in the duct. The key results are that the (6,0) was completely eliminated at the 920 Hz design frequency and substantially reduced elsewhere. The total tone power was reduced 6.8 dB (out of a possible 9.8 dB). Farfield reductions of 15 dB (SPL) were obtained. The (4,0) and (4,1) modes were reduced simultaneously yielding a 15 dB PWL decrease. The results indicate that global attenuation of PWL at the target frequency was obtained in the aft quadrant using an ANC actuator and sensor system totally contained within the duct. The quality of the results depended on precise mode generation. High spillover into spurious modes generated by the ANC actuator array caused less than optimum levels of PWL reduction. The variation in spillover is believed to be due to calibration procedure, but must be confirmed in subsequent tests.

Newtonian-noise cancellation in large-scale interferometric GW detectors using seismic tiltmeters

International Nuclear Information System (INIS)

Harms, Jan; Venkateswara, Krishna

2016-01-01

The mitigation of terrestrial gravity noise, also known as Newtonian noise (NN), is one of the foremost challenges to improve low-frequency sensitivity of ground-based gravitational-wave detectors. At frequencies above 1 Hz, it is predicted that gravity noise from seismic surface Rayleigh waves is the dominant contribution to NN in surface detectors, and may still contribute significantly in future underground detectors. Noise cancellation based on a coherent estimate of NN using data from a seismometer array was proposed in the past. In this article, we propose an alternative scheme to cancel NN using a seismic tiltmeter. It is shown that even under pessimistic assumptions concerning the complexity of the seismic field, a single tiltmeter under each test mass of the detector is sufficient to achieve substantial noise cancellation. A technical tiltmeter design is presented to achieve the required sensitivity in the Newtonian-noise frequency band. (paper)

Characteristics of noise-canceling headphones to reduce the hearing hazard for MP3 users.

Science.gov (United States)

Liang, Maojin; Zhao, Fei; French, David; Zheng, Yiqing

2012-06-01

Three pairs of headphones [standard iPod ear buds and two noise-canceling headphones (NCHs)] were chosen to investigate frequency characteristics of noise reduction, together with their attenuation effects on preferred listening levels (PLLs) in the presence of various types of background noise. Twenty-six subjects with normal hearing chose their PLLs in quiet, street noise, and subway noise using the three headphones and with the noise-canceling system on/off. Both sets of NCHs reduced noise levels at mid- and high-frequencies. Further noise reductions occurred in low frequencies with the noise canceling system switched on. In street noise, both NCHs had similar noise reduction effects. In subway noise, better noise reduction effects were found in the expensive NCH and with noise-canceling on. A two way repeated measures analysis of variance showed that both listening conditions and headphone styles were significant influencing factors on the PLLs. Subjects tended to increase their PLLs as the background noise level increased. Compared with ear buds, PLLs obtained from NCHs-on in the presence of background noise were reduced up to 4 dB. Therefore, proper selection and use of NCHs appears beneficial in reducing the risk of hearing damage caused by high music listening levels in the presence of background noise.

Study of Noise Canceling Performance of Feedforward Fuzzy-Based ANC System under Non-Causal Condition

DEFF Research Database (Denmark)

Mojallali, Hamed; Izadi-Zamanabadi, Roozbeh; Amini, Rouzbeh

of noise canceling performance of feed-forward fuzzy-based ANC systems for ducts under non-causal condition is presented. For this purpose, we use fuzzy filtered-x algorithm as an adaptive filter and the results are compared with classical filteredx algorithm which is employed under the same conditions......Feed-forward active noise control (ANC) systems act as adaptive systems to control and cancel undesired signals and noises. If the delay in the noise canceling subsystems increases more than the delays in the primary path, non-causal condition will occur in these systems. In this paper, study....... Analysis shows that ANC systems using fuzzy algorithm has better efficiency for noise cancellation in non-causal condition....

Novel Acoustic Feedback Cancellation Approaches In Hearing Aid Applications Using Probe Noise and Probe Noise Enhancement

DEFF Research Database (Denmark)

Guo, Meng; Jensen, Søren Holdt; Jensen, Jesper

2012-01-01

. In many cases, this bias problem causes the cancellation system to fail. The traditional probe noise approach, where a noise signal is added to the loudspeaker signal can, in theory, prevent the bias. However, in practice, the probe noise level must often be so high that the noise is clearly audible...... and annoying; this makes the traditional probe noise approach less useful in practical applications. In this work, we explain theoretically the decreased convergence rate when using low-level probe noise in the traditional approach, before we propose and study analytically two new probe noise approaches...... the proposed approaches much more attractive in practical applications. We demonstrate this through a simulation experiment with audio signals in a hearing aid acoustic feedback cancellation system, where the convergence rate is improved by as much as a factor of 10....

Use of active noise cancellation devices in caregivers in the intensive care unit.

Science.gov (United States)

Akhtar, S; Weigle, C G; Cheng, E Y; Toohill, R; Berens, R J

2000-04-01

Recent development of noise cancellation devices may offer relief from noise in the intensive care unit environment. This study was conducted to evaluate the effect of noise cancellation devices on subjective hearing assessment by caregivers in the intensive care units. Randomized, double-blind. Adult medical intensive care unit and pediatric intensive care unit of a teaching hospital. Caregivers of patients, including nurses, parents, respiratory therapists, and nursing assistants from a medical intensive care unit and pediatric intensive care, were enrolled in the study. Each participant was asked to wear the headphones, functional or nonfunctional noise cancellation devices, for a minimum of 30 mins. Subjective ambient noise level was assessed on a 10-point visual analog scale (VAS) before and during headphone use by each participant. Headphone comfort and the preference of the caregiver to wear the headphone were also evaluated on a 10-point VAS. Simultaneously, objective measurement of noise was done with a sound level meter using the decibel-A scale and at each of nine octave bands at each bedspace. The functional headphones significantly reduced the subjective assessment of noise by 2 (out of 10) VAS points (p noise profiles, based on decibel-A and octave band assessments. Noise cancellation devices improve subjective assessment of noise in caretakers. The benefit of these devices on hearing loss needs further evaluation in caregivers and critically ill patients.

Amplifiers Exploiting Thermal Noise Canceling: A Review

OpenAIRE

Klumperink, Eric A.M.; Bruccoleri, Federico; Stroet, Peter; Nauta, Bram

2004-01-01

Wide-band LNAs suffer from a fundamental trade-off between noise figure NF and source impedance matching, which limits NF to values typically above 3dB. Recently, a feed-forward noise canceling technique has been proposed to break this trade-off. This paper reviews the principle of the technique and its key properties. Although the technique has been applied to wideband CMOS LNAs, it can just as well be implemented exploiting transconductance elements realized with oth...

Cancelation and its simulation using Matlab according to active noise control case study of automotive noise silencer

Science.gov (United States)

Alfisyahrin; Isranuri, I.

2018-02-01

Active Noise Control is a technique to overcome noisy with noise or sound countered with sound in scientific terminology i.e signal countered with signals. This technique can be used to dampen relevant noise in accordance with the wishes of the engineering task and reducing automotive muffler noise to a minimum. Objective of this study is to develop a Active Noise Control which should cancel the noise of automotive Exhaust (Silencer) through Signal Processing Simulation methods. Noise generator of Active Noise Control is to make the opponent signal amplitude and frequency of the automotive noise. The steps are: Firstly, the noise of automotive silencer was measured to characterize the automotive noise that its amplitude and frequency which intended to be expressed. The opposed sound which having similar character with the signal source should be generated by signal function. A comparison between the data which has been completed with simulation calculations Fourier transform field data is data that has been captured on the muffler (noise silencer) Toyota Kijang Capsule assembly 2009. MATLAB is used to simulate how the signal processing noise generated by exhaust (silencer) using FFT. This opponent is inverted phase signal from the signal source 180° conducted by Instruments of Signal Noise Generators. The process of noise cancelation examined through simulation using computer software simulation. The result is obtained that attenuation of sound (noise cancellation) has a difference of 33.7%. This value is obtained from the comparison of the value of the signal source and the signal value of the opponent. So it can be concluded that the noisy signal can be attenuated by 33.7%.

Thermal Noise Canceling in LNAs: A Review

OpenAIRE

Nauta, Bram; Klumperink, Eric A.M.; Bruccoleri, Frederico

2004-01-01

Most wide-band amplifiers suffer from a fundamental trade-off between noise figure NF and source impedance matching, which limits NF to values typically above 3dB. Recently, a feed-forward noise canceling technique has been proposed to break this trade-off. This paper reviews the principle of the technique and its key properties. Although the technique has been applied to wideband CMOS LNAs, it can just as well be implemented exploiting transconductance elements realized with other types of t...

A Tunable Low Noise Active Bandpass Filter Using a Noise Canceling Technique

OpenAIRE

Soltani, N.

2016-01-01

A monolithic tunable low noise active bandpass filter is presented in this study. Biasing voltages can control the center frequency and quality factor. By keeping the gain constant, the center frequency shift is 300 MHz. The quality factor can range from 90 to 290 at the center frequency. By using a noise cancelling circuit, noise is kept lower than 2.8 dB. The proposed filter is designed using MMIC technology with a center frequency of 2.4 GHz and a power consumption of 180 mW. ED02AH techno...

Laboratory Investigation of Noise-Canceling Headphones Utilizing "Mr. Blockhead"

Science.gov (United States)

Koser, John

2013-01-01

While I was co-teaching an introductory course in musical acoustics a few years ago, our class investigated several pieces of equipment designed for audio purposes. One piece of such equipment was a pair of noise-canceling headphones. Our students were curious as to how these devices were in eliminating background noise and whether they indeed…

A wideband Noise-Canceling CMOS LNA exploiting a transformer

NARCIS (Netherlands)

Blaakmeer, S.C.; Klumperink, Eric A.M.; Leenaerts, Domine M.W.; Nauta, Bram

2006-01-01

Abstract — A broadband LNA incorporating single-ended to differential conversion, has been successfully implemented using a noise-canceling technique and a single on-chip transformer. The LNA achieves a high voltage gain of 19dB, a wideband input match (2.5–4.0 GHz), and a Noise Figure of 4–5.4 dB,

A wideband Noise-Canceling CMOS LNA exploiting a transformer

NARCIS (Netherlands)

Blaakmeer, S.C.; Klumperink, Eric A.M.; Leenaerts, Domine M.W.; Nauta, Bram

2006-01-01

A broadband LNA incorporating single-ended to differential conversion, has been successfully implemented using a noise-canceling technique and a single on-chip transformer. The LNA achieves a high voltage gain of 19dB, a wideband input match (2.5–4.0 GHz), and a Noise Figure of 4–5.4 dB, while

Background Noise Reduction Using Adaptive Noise Cancellation Determined by the Cross-Correlation

Science.gov (United States)

Spalt, Taylor B.; Brooks, Thomas F.; Fuller, Christopher R.

2012-01-01

Background noise due to flow in wind tunnels contaminates desired data by decreasing the Signal-to-Noise Ratio. The use of Adaptive Noise Cancellation to remove background noise at measurement microphones is compromised when the reference sensor measures both background and desired noise. The technique proposed modifies the classical processing configuration based on the cross-correlation between the reference and primary microphone. Background noise attenuation is achieved using a cross-correlation sample width that encompasses only the background noise and a matched delay for the adaptive processing. A present limitation of the method is that a minimum time delay between the background noise and desired signal must exist in order for the correlated parts of the desired signal to be separated from the background noise in the crosscorrelation. A simulation yields primary signal recovery which can be predicted from the coherence of the background noise between the channels. Results are compared with two existing methods.

A Tunable Low Noise Active Bandpass Filter Using a Noise Canceling Technique

Directory of Open Access Journals (Sweden)

N. Soltani

2016-12-01

Full Text Available A monolithic tunable low noise active bandpass filter is presented in this study. Biasing voltages can control the center frequency and quality factor. By keeping the gain constant, the center frequency shift is 300 MHz. The quality factor can range from 90 to 290 at the center frequency. By using a noise cancelling circuit, noise is kept lower than 2.8 dB. The proposed filter is designed using MMIC technology with a center frequency of 2.4 GHz and a power consumption of 180 mW. ED02AH technology is used to simulate the circuit elements.

Laboratory Investigation of Noise-Canceling Headphones Utilizing ``Mr. Blockhead''

Science.gov (United States)

Koser, John

2013-09-01

While I was co-teaching an introductory course in musical acoustics a few years ago, our class investigated several pieces of equipment designed for audio purposes. One piece of such equipment was a pair of noise-canceling headphones. Our students were curious as to how these devices were in eliminating background noise and whether they indeed block low-frequency sounds as advertised.

Newtonian noise cancellation in tensor gravitational wave detector

International Nuclear Information System (INIS)

Paik, Ho Jung; Harms, Jan

2016-01-01

Terrestrial gravity noise produced by ambient seismic and infrasound fields poses one of the main sensitivity limitations in low-frequency ground-based gravitational-wave (GW) detectors. This noise needs to be suppressed by 3-5 orders of magnitude in the frequency band 10 mHz to 1 Hz, which is extremely challenging. We present a new approach that greatly facilitates cancellation of gravity noise in full-tensor GW detectors. It makes explicit use of the direction of propagation of a GW, and can therefore either be implemented in directional searches for GWs or in observations of known sources. We show that suppression of the Newtonian-noise foreground is greatly facilitated using the extra strain channels in full-tensor GW detectors. Only a modest number of auxiliary, high-sensitivity environmental sensors is required to achieve noise suppression by a few orders of magnitude. (paper)

On-line adaptive line frequency noise cancellation from a nuclear power measuring channel

Directory of Open Access Journals (Sweden)

Qadir Javed

2011-01-01

Full Text Available On-line software for adaptively canceling 50 Hz line frequency noise has been designed and tested at Pakistan Research Reactor 1. Line frequency noise causes much problem in weak signals acquisition. Sometimes this noise is so dominant that original signal is totally corrupted. Although notch filter can be used for eliminating this noise, but if signal of interest is in close vicinity of 50 Hz, then original signal is also attenuated and hence overall performance is degraded. Adaptive noise removal is a technique which could be employed for removing line frequency without degrading the desired signal. In this paper line frequency noise has been eliminated on-line from a nuclear power measuring channel. The adaptive LMS algorithm has been used to cancel 50 Hz noise. The algorithm has been implemented in labVIEW with NI 6024 data acquisition card. The quality of the acquired signal has been improved much as can be seen in experimental results.

Investigation of LO-leakage cancellation and DC-offset influence on flicker-noise in X-band mixers

DEFF Research Database (Denmark)

Michaelsen, Rasmus; Johansen, Tom; Tamborg, Kjeld

2012-01-01

This paper describes an investigation on the influences in 1/f noise of LO-leakage and DC-offset cancellation for X-band mixers. Conditions for LO-leakage cancellation and zero DC-offset is derived. Measurements on a double balanced diode mixer shows an improvement in noise figure from 14.3dB to ...

25 CFR 141.57 - Procedures to cancel liability on bond.

Science.gov (United States)

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Procedures to cancel liability on bond. 141.57 Section 141.57 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FINANCIAL ACTIVITIES BUSINESS... Procedures to cancel liability on bond. (a) Any surety who wishes to be relieved from liability arising on a...

Comparative study of adaptive-noise-cancellation algorithms for intrusion detection systems

International Nuclear Information System (INIS)

Claassen, J.P.; Patterson, M.M.

1981-01-01

Some intrusion detection systems are susceptible to nonstationary noise resulting in frequent nuisance alarms and poor detection when the noise is present. Adaptive inverse filtering for single channel systems and adaptive noise cancellation for two channel systems have both demonstrated good potential in removing correlated noise components prior detection. For such noise susceptible systems the suitability of a noise reduction algorithm must be established in a trade-off study weighing algorithm complexity against performance. The performance characteristics of several distinct classes of algorithms are established through comparative computer studies using real signals. The relative merits of the different algorithms are discussed in the light of the nature of intruder and noise signals

Inference from the futures: ranking the noise cancelling accuracy of realized measures

DEFF Research Database (Denmark)

Mirone, Giorgio

We consider the log-linear relationship between futures contracts and their underlying assets and show that in the classical Brownian semi-martingale (BSM) framework the two series must, by no-arbitrage, have the same integrated variance. We then introduce the concept of noise cancelling...... measures in the presence of noise. Moreover, a thorough simulation analysis is employed to evaluate the estimators' sensitivity to different price and noise processes, and sampling frequencies....

Force sensing based on coherent quantum noise cancellation in a hybrid optomechanical cavity with squeezed-vacuum injection

Science.gov (United States)

Motazedifard, Ali; Bemani, F.; Naderi, M. H.; Roknizadeh, R.; Vitali, D.

2016-07-01

We propose and analyse a feasible experimental scheme for a quantum force sensor based on the elimination of backaction noise through coherent quantum noise cancellation (CQNC) in a hybrid atom-cavity optomechanical setup assisted with squeezed vacuum injection. The force detector, which allows for a continuous, broadband detection of weak forces well below the standard quantum limit (SQL), is formed by a single optical cavity simultaneously coupled to a mechanical oscillator and to an ensemble of ultracold atoms. The latter acts as a negative-mass oscillator so that atomic noise exactly cancels the backaction noise from the mechanical oscillator due to destructive quantum interference. Squeezed vacuum injection enforces this cancellation and allows sub-SQL sensitivity to be reached in a very wide frequency band, and at much lower input laser powers.

Force sensing based on coherent quantum noise cancellation in a hybrid optomechanical cavity with squeezed-vacuum injection

International Nuclear Information System (INIS)

Motazedifard, Ali; Bemani, F; Naderi, M H; Roknizadeh, R; Vitali, D

2016-01-01

We propose and analyse a feasible experimental scheme for a quantum force sensor based on the elimination of backaction noise through coherent quantum noise cancellation (CQNC) in a hybrid atom-cavity optomechanical setup assisted with squeezed vacuum injection. The force detector, which allows for a continuous, broadband detection of weak forces well below the standard quantum limit (SQL), is formed by a single optical cavity simultaneously coupled to a mechanical oscillator and to an ensemble of ultracold atoms. The latter acts as a negative-mass oscillator so that atomic noise exactly cancels the backaction noise from the mechanical oscillator due to destructive quantum interference. Squeezed vacuum injection enforces this cancellation and allows sub-SQL sensitivity to be reached in a very wide frequency band, and at much lower input laser powers. (paper)

Active3 noise reduction

International Nuclear Information System (INIS)

Holzfuss, J.

1996-01-01

Noise reduction is a problem being encountered in a variety of applications, such as environmental noise cancellation, signal recovery and separation. Passive noise reduction is done with the help of absorbers. Active noise reduction includes the transmission of phase inverted signals for the cancellation. This paper is about a threefold active approach to noise reduction. It includes the separation of a combined source, which consists of both a noise and a signal part. With the help of interaction with the source by scanning it and recording its response, modeling as a nonlinear dynamical system is achieved. The analysis includes phase space analysis and global radial basis functions as tools for the prediction used in a subsequent cancellation procedure. Examples are given which include noise reduction of speech. copyright 1996 American Institute of Physics

Evaluation of the Performance of Feedforward and Recurrent Neural Networks in Active Cancellation of Sound Noise

Directory of Open Access Journals (Sweden)

Mehrshad Salmasi

2012-07-01

Full Text Available Active noise control is based on the destructive interference between the primary noise and generated noise from the secondary source. An antinoise of equal amplitude and opposite phase is generated and combined with the primary noise. In this paper, performance of the neural networks is evaluated in active cancellation of sound noise. For this reason, feedforward and recurrent neural networks are designed and trained. After training, performance of the feedforwrad and recurrent networks in noise attenuation are compared. We use Elman network as a recurrent neural network. For simulations, noise signals from a SPIB database are used. In order to compare the networks appropriately, equal number of layers and neurons are considered for the networks. Moreover, training and test samples are similar. Simulation results show that feedforward and recurrent neural networks present good performance in noise cancellation. As it is seen, the ability of recurrent neural network in noise attenuation is better than feedforward network.

Design and analysis of a BLPC vocoder-based adaptive feedback cancellation with probe noise

DEFF Research Database (Denmark)

Anand, Ankita; Kar, Asutosh; Swamy, M.N.S.

2017-01-01

a BLPC vocoderbased adaptive feedback canceller with probe noise with an objective of reducing the low-frequency bias in digital hearing-aids. A step-wise mathematical analysis of the proposed feedback canceller is presented employing the recursive least square and normalized least mean square adaptive......The band-limited linear predictive coding (BLPC) vocoder-based adaptive feedback cancellation (AFC) removes the high-frequency bias, while the low frequency bias persists between the desired input signal and the loudspeaker signal in the estimate of the feedback path. In this paper, we present...... algorithms. It is observed that the optimal solution of the feedback path is unbiased for an unshaped probe noise, but is biased for a shaped probe signal; the bias term does not consist of correlation between the desired input and the loudspeaker output. The identifiability conditions are analysed...

Multireference adaptive noise canceling applied to the EEG.

Science.gov (United States)

James, C J; Hagan, M T; Jones, R D; Bones, P J; Carroll, G J

1997-08-01

The technique of multireference adaptive noise canceling (MRANC) is applied to enhance transient nonstationarities in the electroeancephalogram (EEG), with the adaptation implemented by means of a multilayer-perception artificial neural network (ANN). The method was applied to recorded EEG segments and the performance on documented nonstationarities recorded. The results show that the neural network (nonlinear) gives an improvement in performance (i.e., signal-to-noise ratio (SNR) of the nonstationarities) compared to a linear implementation of MRANC. In both cases an improvement in the SNR was obtained. The advantage of the spatial filtering aspect of MRANC is highlighted when the performance of MRANC is compared to that of the inverse auto-regressive filtering of the EEG, a purely temporal filter.

High Dynamic Range RF Front End with Noise Cancellation and Linearization for WiMAX Receivers

Directory of Open Access Journals (Sweden)

J.-M. Wu

2012-06-01

Full Text Available This research deals with verification of the high dynamic range for a heterodyne radio frequency (RF front end. A 2.6 GHz RF front end is designed and implemented in a hybrid microwave integrated circuit (HMIC for worldwide interoperability for microwave access (WiMAX receivers. The heterodyne RF front end consists of a low-noise amplifier (LNA with noise cancellation, an RF bandpass filter (BPF, a downconverter with linearization, and an intermediate frequency (IF BPF. A noise canceling technique used in the low-noise amplifier eliminates a thermal noise and then reduces the noise figure (NF of the RF front end by 0.9 dB. Use of a downconverter with diode linearizer also compensates for gain compression, which increases the input-referred third-order intercept point (IIP3 of the RF front end by 4.3 dB. The proposed method substantially increases the spurious-free dynamic range (DRf of the RF front end by 3.5 dB.

A Background Noise Reduction Technique Using Adaptive Noise Cancellation for Microphone Arrays

Science.gov (United States)

Spalt, Taylor B.; Fuller, Christopher R.; Brooks, Thomas F.; Humphreys, William M., Jr.; Brooks, Thomas F.

2011-01-01

Background noise in wind tunnel environments poses a challenge to acoustic measurements due to possible low or negative Signal to Noise Ratios (SNRs) present in the testing environment. This paper overviews the application of time domain Adaptive Noise Cancellation (ANC) to microphone array signals with an intended application of background noise reduction in wind tunnels. An experiment was conducted to simulate background noise from a wind tunnel circuit measured by an out-of-flow microphone array in the tunnel test section. A reference microphone was used to acquire a background noise signal which interfered with the desired primary noise source signal at the array. The technique s efficacy was investigated using frequency spectra from the array microphones, array beamforming of the point source region, and subsequent deconvolution using the Deconvolution Approach for the Mapping of Acoustic Sources (DAMAS) algorithm. Comparisons were made with the conventional techniques for improving SNR of spectral and Cross-Spectral Matrix subtraction. The method was seen to recover the primary signal level in SNRs as low as -29 dB and outperform the conventional methods. A second processing approach using the center array microphone as the noise reference was investigated for more general applicability of the ANC technique. It outperformed the conventional methods at the -29 dB SNR but yielded less accurate results when coherence over the array dropped. This approach could possibly improve conventional testing methodology but must be investigated further under more realistic testing conditions.

Hardware Implementation of LMS-Based Adaptive Noise Cancellation Core with Low Resource Utilization

Directory of Open Access Journals (Sweden)

Omid Sharifi Tehrani

2011-10-01

Full Text Available A hardware implementation of adaptive noise cancellation (ANC core is proposed. Adaptive filters are widely used in different applications such as adaptive noise cancellation, prediction, equalization, inverse modeling and system identification. FIR adaptive filters are mostly used because of their low computation costs and their linear phase. Least mean squared algorithm (LMS is used to train FIR adaptive filter weights. Advances in semiconductor technology especially in digital signal processors (DSP and field programmable gate arrays (FPGA with hundreds of mega hertz in speed, will allow digital designers to embed essential digital signal processing units in small chips. But designing a synthesizable core on an FPGA is not always as simple as DSP chips due to complexity and limitations of FPGAs. In this paper we design anLMS-based FIR adaptive filter for adaptive noise cancellation based on VHDL97 hardware description language (HDL and Xilinx SPARTAN3E (XC3S500E which utilizes low resources and is high performance and FPGA-brand independent so can be implemented on different FPGA brands (Xilinx, ALTERA, ACTEL. Simulations are done in MODELSIM and MATLAB and implementation is done with Xilinx ISE. Finally, result are compared with other papers for better judgment.

Noise-cancelled, cavity-enhanced saturation laser spectroscopy for laser frequency stabilisation

International Nuclear Information System (INIS)

Vine, Glenn de; McClelland, David E; Gray, Malcolm B

2006-01-01

We employ a relatively simple experimental technique enabling mechanical-noise free, cavityenhanced spectroscopic measurements of an atomic transition and its hyperfine structure. We demonstrate this technique with the 532 nm frequency doubled output from a Nd:YAG laser and an iodine vapour cell. The resulting cavity-enhanced, noise-cancelled, iodine hyperfine error signal is used as a frequency reference with which we stabilise the frequency of the 1064nm Nd:YAG laser. Preliminary frequency stabilisation results are then presented

Carbon Nanotube Thin Films for Active Noise Cancellation, Solar Energy Harvesting, and Energy Storage in Building Windows

Science.gov (United States)

Hu, Shan

This research explores the application of carbon nanotube (CNT) films for active noise cancellation, solar energy harvesting and energy storage in building windows. The CNT-based components developed herein can be integrated into a solar-powered active noise control system for a building window. First, the use of a transparent acoustic transducer as both an invisible speaker for auxiliary audio playback and for active noise cancellation is accomplished in this work. Several challenges related to active noise cancellation in the window are addressed. These include secondary path estimation and directional cancellation of noise so as to preserve auxiliary audio and internal sounds while preventing transmission of external noise into the building. Solar energy can be harvested at a low rate of power over long durations while acoustic sound cancellation requires short durations of high power. A supercapacitor based energy storage system is therefore considered for the window. Using CNTs as electrode materials, two generations of flexible, thin, and fully solid-state supercapacitors are developed that can be integrated into the window frame. Both generations consist of carbon nanotube films coated on supporting substrates as electrodes and a solid-state polymer gel layer for the electrolyte. The first generation is a single-cell parallel-plate supercapacitor with a working voltage of 3 Volts. Its energy density is competitive with commercially available supercapacitors (which use liquid electrolyte). For many applications that will require higher working voltage, the second-generation multi-cell supercapacitor is developed. A six-cell device with a working voltage as high as 12 Volts is demonstrated here. Unlike the first generation's 3D structure, the second generation has a novel planar (2D) architecture, which makes it easy to integrate multiple cells into a thin and flexible supercapacitor. The multi-cell planar supercapacitor has energy density exceeding that of

A Hybrid Semi-Digital Transimpedance Amplifier With Noise Cancellation Technique for Nanopore-Based DNA Sequencing.

Science.gov (United States)

Hsu, Chung-Lun; Jiang, Haowei; Venkatesh, A G; Hall, Drew A

2015-10-01

Over the past two decades, nanopores have been a promising technology for next generation deoxyribonucleic acid (DNA) sequencing. Here, we present a hybrid semi-digital transimpedance amplifier (HSD-TIA) to sense the minute current signatures introduced by single-stranded DNA (ssDNA) translocating through a nanopore, while discharging the baseline current using a semi-digital feedback loop. The amplifier achieves fast settling by adaptively tuning a DC compensation current when a step input is detected. A noise cancellation technique reduces the total input-referred current noise caused by the parasitic input capacitance. Measurement results show the performance of the amplifier with 31.6 M Ω mid-band gain, 950 kHz bandwidth, and 8.5 fA/ √Hz input-referred current noise, a 2× noise reduction due to the noise cancellation technique. The settling response is demonstrated by observing the insertion of a protein nanopore in a lipid bilayer. Using the nanopore, the HSD-TIA was able to measure ssDNA translocation events.

Transient plasma estimation: a noise cancelling/identification approach

International Nuclear Information System (INIS)

Candy, J.V.; Casper, T.; Kane, R.

1985-03-01

The application of a noise cancelling technique to extract energy storage information from sensors occurring during fusion reactor experiments on the Tandem Mirror Experiment-Upgrade (TMX-U) at the Lawrence Livermore National Laboratory (LLNL) is examined. We show how this technique can be used to decrease the uncertainty in the corresponding sensor measurements used for diagnostics in both real-time and post-experimental environments. We analyze the performance of algorithm on the sensor data and discuss the various tradeoffs. The algorithm suggested is designed using SIG, an interactive signal processing package developed at LLNL

Self-Interference Cancellation Using Time-Domain Phase Noise Estimation in OFDM Full-Duplex Systems

OpenAIRE

Shehata, Heba; Khattab, Tamer

2016-01-01

In full-duplex systems, oscillator phase noise (PN) problem is considered the bottleneck challenge that may face the self-interference cancellation (SIC) stage especially when orthogonal frequency division multiplexing (OFDM) transmission scheme is deployed. Phase noise degrades the SIC performance significantly, if not mitigated before or during the SIC technique. The presence of the oscillator phase noise has different impacts on the transmitted data symbol like common phase error (CPE) and...

An OFDM Receiver with Frequency Domain Diversity Combined Impulsive Noise Canceller for Underwater Network

Science.gov (United States)

Saotome, Rie; Hai, Tran Minh; Matsuda, Yasuto; Suzuki, Taisaku; Wada, Tomohisa

2015-01-01

In order to explore marine natural resources using remote robotic sensor or to enable rapid information exchange between ROV (remotely operated vehicles), AUV (autonomous underwater vehicle), divers, and ships, ultrasonic underwater communication systems are used. However, if the communication system is applied to rich living creature marine environment such as shallow sea, it suffers from generated Impulsive Noise so-called Shrimp Noise, which is randomly generated in time domain and seriously degrades communication performance in underwater acoustic network. With the purpose of supporting high performance underwater communication, a robust digital communication method for Impulsive Noise environments is necessary. In this paper, we propose OFDM ultrasonic communication system with diversity receiver. The main feature of the receiver is a newly proposed Frequency Domain Diversity Combined Impulsive Noise Canceller. The OFDM receiver utilizes 20–28 KHz ultrasonic channel and subcarrier spacing of 46.875 Hz (MODE3) and 93.750 Hz (MODE2) OFDM modulations. In addition, the paper shows Impulsive Noise distribution data measured at a fishing port in Okinawa and at a barge in Shizuoka prefectures and then proposed diversity OFDM transceivers architecture and experimental results are described. By the proposed Impulsive Noise Canceller, frame bit error rate has been decreased by 20–30%. PMID:26351656

An OFDM Receiver with Frequency Domain Diversity Combined Impulsive Noise Canceller for Underwater Network.

Science.gov (United States)

Saotome, Rie; Hai, Tran Minh; Matsuda, Yasuto; Suzuki, Taisaku; Wada, Tomohisa

2015-01-01

In order to explore marine natural resources using remote robotic sensor or to enable rapid information exchange between ROV (remotely operated vehicles), AUV (autonomous underwater vehicle), divers, and ships, ultrasonic underwater communication systems are used. However, if the communication system is applied to rich living creature marine environment such as shallow sea, it suffers from generated Impulsive Noise so-called Shrimp Noise, which is randomly generated in time domain and seriously degrades communication performance in underwater acoustic network. With the purpose of supporting high performance underwater communication, a robust digital communication method for Impulsive Noise environments is necessary. In this paper, we propose OFDM ultrasonic communication system with diversity receiver. The main feature of the receiver is a newly proposed Frequency Domain Diversity Combined Impulsive Noise Canceller. The OFDM receiver utilizes 20-28 KHz ultrasonic channel and subcarrier spacing of 46.875 Hz (MODE3) and 93.750 Hz (MODE2) OFDM modulations. In addition, the paper shows Impulsive Noise distribution data measured at a fishing port in Okinawa and at a barge in Shizuoka prefectures and then proposed diversity OFDM transceivers architecture and experimental results are described. By the proposed Impulsive Noise Canceller, frame bit error rate has been decreased by 20-30%.

An OFDM Receiver with Frequency Domain Diversity Combined Impulsive Noise Canceller for Underwater Network

Directory of Open Access Journals (Sweden)

Rie Saotome

2015-01-01

Full Text Available In order to explore marine natural resources using remote robotic sensor or to enable rapid information exchange between ROV (remotely operated vehicles, AUV (autonomous underwater vehicle, divers, and ships, ultrasonic underwater communication systems are used. However, if the communication system is applied to rich living creature marine environment such as shallow sea, it suffers from generated Impulsive Noise so-called Shrimp Noise, which is randomly generated in time domain and seriously degrades communication performance in underwater acoustic network. With the purpose of supporting high performance underwater communication, a robust digital communication method for Impulsive Noise environments is necessary. In this paper, we propose OFDM ultrasonic communication system with diversity receiver. The main feature of the receiver is a newly proposed Frequency Domain Diversity Combined Impulsive Noise Canceller. The OFDM receiver utilizes 20–28 KHz ultrasonic channel and subcarrier spacing of 46.875 Hz (MODE3 and 93.750 Hz (MODE2 OFDM modulations. In addition, the paper shows Impulsive Noise distribution data measured at a fishing port in Okinawa and at a barge in Shizuoka prefectures and then proposed diversity OFDM transceivers architecture and experimental results are described. By the proposed Impulsive Noise Canceller, frame bit error rate has been decreased by 20–30%.

Phase noise cancellation in polarisation-maintaining fibre links

Science.gov (United States)

Rauf, B.; Vélez López, M. C.; Thoumany, P.; Pizzocaro, M.; Calonico, D.

2018-03-01

The distribution of ultra-narrow linewidth laser radiation is an integral part of many challenging metrological applications. Changes in the optical pathlength induced by environmental disturbances compromise the stability and accuracy of optical fibre networks distributing the laser light and call for active phase noise cancellation. Here we present a laboratory scale optical (at 578 nm) fibre network featuring all polarisation maintaining fibres in a setup with low optical powers available and tracking voltage-controlled oscillators implemented. The stability and accuracy of this system reach performance levels below 1 × 10-19 after 10 000 s of averaging.

Evaluation of the Performance of Feedforward and Recurrent Neural Networks in Active Cancellation of Sound Noise

OpenAIRE

Mehrshad Salmasi; Homayoun Mahdavi-Nasab

2012-01-01

Active noise control is based on the destructive interference between the primary noise and generated noise from the secondary source. An antinoise of equal amplitude and opposite phase is generated and combined with the primary noise. In this paper, performance of the neural networks is evaluated in active cancellation of sound noise. For this reason, feedforward and recurrent neural networks are designed and trained. After training, performance of the feedforwrad and recurrent networks in n...

A wideband CMOS inductorless low noise amplifier employing noise cancellation for digital TV tuner applications

International Nuclear Information System (INIS)

Zhang Jihong; Bai Xuefei; Huang Lu

2013-01-01

A wideband inductorless low noise amplifier for digital TV tuner applications is presented. The proposed LNA scheme uses a composite NMOS/PMOS cross-coupled transistor pair to provide partial cancellation of noise generated by the input transistors. The chip is implemented in SMIC 0.18 μm CMOS technology. Measurement shows that the proposed LNA achieves 12.2–15.2 dB voltage gain from 300 to 900 MHz, the noise figure is below 3.1 dB and has a minimum value of 2.3 dB, and the best input-referred 1-dB compression point (IP1dB) is − 17 dBm at 900 MHz. The core consumes 7 mA current with a supply voltage of 1.8 V and occupies an area of 0.5 × 0.35 mm 2 . (semiconductor integrated circuits)

Towards a first design of a Newtonian-noise cancellation system for Advanced LIGO

International Nuclear Information System (INIS)

Coughlin, M; Mukund, N; Mitra, S; Harms, J; Driggers, J; Adhikari, R

2016-01-01

Newtonian gravitational noise from seismic fields is predicted to be a limiting noise source at low frequency for second generation gravitational-wave detectors. Mitigation of this noise will be achieved by Wiener filtering using arrays of seismometers deployed in the vicinity of all test masses. In this work, we present optimized configurations of seismometer arrays using a variety of simplified models of the seismic field based on seismic observations at LIGO Hanford. The model that best fits the seismic measurements leads to noise reduction limited predominantly by seismometer self-noise. A first simplified design of seismic arrays for Newtonian-noise cancellation at the LIGO sites is presented, which suggests that it will be sufficient to monitor surface displacement inside the buildings. (paper)

A single-ended CMOS sensing circuit for MEMS gyroscope with noise cancellation

KAUST Repository

Elsayed, Mohannad Yomn

2010-06-01

In this work, a complete single-ended readout circuit for capacitive MEMS gyroscope using chopper stabilization technique is presented. A novel noise cancellation technique is used to get rid of the bias noise. The circuit offers superior performance over state of the art readout circuits in terms of cost, gain, and noise for the given area and power consumption. The full circuit exhibits a gain of 58dB, a power dissipation of 1.3mW and an input referred noise of 12nV/√Hz. This would significantly improve the overall sensitivity of the gyroscope. The full circuit has been fabricated in 0.6um CMOS technology and it occupies an area of 0.4mm × 1mm. © 2010 IEEE.

A single-ended CMOS sensing circuit for MEMS gyroscope with noise cancellation

KAUST Repository

Elsayed, Mohannad Yomn; Emira, Ahmed; Sedky, Sherif M.; Habib, S. E. D.

2010-01-01

In this work, a complete single-ended readout circuit for capacitive MEMS gyroscope using chopper stabilization technique is presented. A novel noise cancellation technique is used to get rid of the bias noise. The circuit offers superior performance over state of the art readout circuits in terms of cost, gain, and noise for the given area and power consumption. The full circuit exhibits a gain of 58dB, a power dissipation of 1.3mW and an input referred noise of 12nV/√Hz. This would significantly improve the overall sensitivity of the gyroscope. The full circuit has been fabricated in 0.6um CMOS technology and it occupies an area of 0.4mm × 1mm. © 2010 IEEE.

Joint Use of Adaptive Equalization and Cyclic Noise Cancellation for Band-Limited OQAM Based Multi-Carrier Transmission in Power-Line Communication Systems

Science.gov (United States)

Kunishima, Hiromitsu; Koga, Hisao; Muta, Osamu; Akaiwa, Yoshihiko

Power-line communication (PLC) technique is one method to realize high-speed communications in a home network. In PLC channels, the transmission signal quality is degraded by colored non-Gaussian noise as well as frequency-selectivity of the channels. In this paper, we describe our investigation of the performance of a OQAM-MCT system in which a noise canceller is used jointly with a time-domain per-subcarrier adaptive equalizer. Furthermore, we propose a noise cancellation method designed for the OQAM-MCT system. The performance of the OQAM-MCT system is evaluated in PLC channels with measured impulse responses in the presence of measured noise. Computer simulation results show that the bit rate of the OQAM-MCT system is improved using both an adaptive equalizer and noise canceller, and that the OQAM-MCT system achieves better performance than an OFDM system with an insufficient length of the guard interval.

Extraction of Overt Verbal Response from the Acoustic Noise in a Functional Magnetic Resonance Imaging Scan by Use of Segmented Active Noise Cancellation

Science.gov (United States)

Jung, Kwan-Jin; Prasad, Parikshit; Qin, Yulin; Anderson, John R.

2013-01-01

A method to extract the subject's overt verbal response from the obscuring acoustic noise in an fMRI scan is developed by applying active noise cancellation with a conventional MRI microphone. Since the EPI scanning and its accompanying acoustic noise in fMRI are repetitive, the acoustic noise in one time segment was used as a reference noise in suppressing the acoustic noise in subsequent segments. However, the acoustic noise from the scanner was affected by the subject's movements, so the reference noise was adaptively adjusted as the scanner's acoustic properties varied in time. This method was successfully applied to a cognitive fMRI experiment with overt verbal responses. PMID:15723385

A flicker noise/IM3 cancellation technique for active mixer using negative impedance

NARCIS (Netherlands)

Cheng, W.; Annema, Anne J.; Wienk, Gerhardus J.M.; Nauta, Bram

2013-01-01

Abstract—This paper presents an approach to simultaneously cancel flicker noise and IM3 in Gilbert-type mixers, utilizing negative impedances. For proof of concept, two prototype double-balanced mixers in 0.16- m CMOS are fabricated. The first demonstration mixer chip was optimized for full IM3

On Acoustic Feedback Cancellation Using Probe Noise in Multiple-Microphone and Single-Loudspeaker Systems

DEFF Research Database (Denmark)

Guo, Meng; Elmedyb, Thomas Bo; Jensen, Søren Holdt

2012-01-01

of the adaptive estimation is significantly decreased when keeping the steady-state error unchanged. The goal of this work is to derive analytic expressions for the system behavior such as convergence rate and steady-state error for a multiple-microphone and single-loudspeaker audio system, where the acoustic...... feedback cancellation is carried out using a probe noise signal. The derived results show how different system parameters and signal properties affect the cancellation performance, and the results explain theoretically the decreased convergence rate. Understanding this is important for making further...

A wide bandwidth fractional-N synthesizer for LTE with phase noise cancellation using a hybrid-ΔΣ-DAC and charge re-timing

NARCIS (Netherlands)

Ye, D.; Lu, Ping; Andreani, Pietro; van der Zee, Ronan A.R.

2013-01-01

This paper presents a 1MHz bandwidth, ΔΣ fractional-N PLL as the frequency synthesizer for LTE. A noise cancellation path composed of a novel hybrid ΔΣ DAC with 9 output bits is incorporated into the PLL in order to cancel the out-of-band phase noise caused by the quantization error. Further, a

System and method for bearing fault detection using stator current noise cancellation

Science.gov (United States)

Zhou, Wei; Lu, Bin; Habetler, Thomas G.; Harley, Ronald G.; Theisen, Peter J.

2010-08-17

A system and method for detecting incipient mechanical motor faults by way of current noise cancellation is disclosed. The system includes a controller configured to detect indicia of incipient mechanical motor faults. The controller further includes a processor programmed to receive a baseline set of current data from an operating motor and define a noise component in the baseline set of current data. The processor is also programmed to repeatedly receive real-time operating current data from the operating motor and remove the noise component from the operating current data in real-time to isolate any fault components present in the operating current data. The processor is then programmed to generate a fault index for the operating current data based on any isolated fault components.

Benign paroxysmal positional vertigo after use of noise-canceling headphones.

Science.gov (United States)

Dan-Goor, Eric; Samra, Monica

2012-01-01

Benign paroxysmal positional vertigo (BPPV) is a common cause of vertigo. We describe a case of a woman presenting acutely with a severe episode of disabling positional vertigo. Although she had no known etiologic risk factors, this attack followed 12 hours of continuously wearing digital noise-canceling headphones. This is the first such reported association between BPPV and the use of this gadget. We also provide a short review of BPPV and speculate on the possible pathogenic mechanisms involved. Copyright © 2012 Elsevier Inc. All rights reserved.

Transform Domain Robust Variable Step Size Griffiths' Adaptive Algorithm for Noise Cancellation in ECG

Science.gov (United States)

Hegde, Veena; Deekshit, Ravishankar; Satyanarayana, P. S.

2011-12-01

The electrocardiogram (ECG) is widely used for diagnosis of heart diseases. Good quality of ECG is utilized by physicians for interpretation and identification of physiological and pathological phenomena. However, in real situations, ECG recordings are often corrupted by artifacts or noise. Noise severely limits the utility of the recorded ECG and thus needs to be removed, for better clinical evaluation. In the present paper a new noise cancellation technique is proposed for removal of random noise like muscle artifact from ECG signal. A transform domain robust variable step size Griffiths' LMS algorithm (TVGLMS) is proposed for noise cancellation. For the TVGLMS, the robust variable step size has been achieved by using the Griffiths' gradient which uses cross-correlation between the desired signal contaminated with observation or random noise and the input. The algorithm is discrete cosine transform (DCT) based and uses symmetric property of the signal to represent the signal in frequency domain with lesser number of frequency coefficients when compared to that of discrete Fourier transform (DFT). The algorithm is implemented for adaptive line enhancer (ALE) filter which extracts the ECG signal in a noisy environment using LMS filter adaptation. The proposed algorithm is found to have better convergence error/misadjustment when compared to that of ordinary transform domain LMS (TLMS) algorithm, both in the presence of white/colored observation noise. The reduction in convergence error achieved by the new algorithm with desired signal decomposition is found to be lower than that obtained without decomposition. The experimental results indicate that the proposed method is better than traditional adaptive filter using LMS algorithm in the aspects of retaining geometrical characteristics of ECG signal.

System and method for motor fault detection using stator current noise cancellation

Science.gov (United States)

Zhou, Wei; Lu, Bin; Nowak, Michael P.; Dimino, Steven A.

2010-12-07

A system and method for detecting incipient mechanical motor faults by way of current noise cancellation is disclosed. The system includes a controller configured to detect indicia of incipient mechanical motor faults. The controller further includes a processor programmed to receive a baseline set of current data from an operating motor and define a noise component in the baseline set of current data. The processor is also programmed to acquire at least on additional set of real-time operating current data from the motor during operation, redefine the noise component present in each additional set of real-time operating current data, and remove the noise component from the operating current data in real-time to isolate any fault components present in the operating current data. The processor is then programmed to generate a fault index for the operating current data based on any isolated fault components.

Active Electromagnetic Interference Cancelation for Automotive Switch-Mode Audio Power Amplifiers

DEFF Research Database (Denmark)

Knott, Arnold; Pfaffinger, Gerhard; Andersen, Michael A. E.

2009-01-01

Recent trends in the automotive audio industry have shown the importance of active noise cancelation (ANC) for major improvements in mobile entertainment environments. These approaches target the acoustical noise in the cabin and superimpose an inverse noise signal to cancel disturbances. Electro......Recent trends in the automotive audio industry have shown the importance of active noise cancelation (ANC) for major improvements in mobile entertainment environments. These approaches target the acoustical noise in the cabin and superimpose an inverse noise signal to cancel disturbances...

High performance magnetic bearings suitable for noise cancellation in permanent magnet motor driven pumps

International Nuclear Information System (INIS)

Zmood, R.; Cholewka, J.; Patak, C.; Feng, G.; Zhang, C.; Maleri, T.; Pinder, B.; McDonald, R.; Homrigh, J.

1991-01-01

Conventional pumps having external drive motors experience problems due to bearing noise. In addition failure of bearings and seals can lead to limited operational reliability and impaired integrity of these pumps. Pumps using DC brushless motors and magnetic bearings offer means of overcoming these problems. A design of a pump having a DC brushless motor and magnetic bearings with a potential for Naval applications in ships and submarines is discussed. In this paper attention is given to the selection of the magnetic bearings suitable for achieving active noise cancellation

Gravitational wave searches with pulsar timing arrays: Cancellation of clock and ephemeris noises

Science.gov (United States)

Tinto, Massimo

2018-04-01

We propose a data processing technique to cancel monopole and dipole noise sources (such as clock and ephemeris noises, respectively) in pulsar timing array searches for gravitational radiation. These noises are the dominant sources of correlated timing fluctuations in the lower-part (≈10-9-10-8 Hz ) of the gravitational wave band accessible by pulsar timing experiments. After deriving the expressions that reconstruct these noises from the timing data, we estimate the gravitational wave sensitivity of our proposed processing technique to single-source signals to be at least one order of magnitude higher than that achievable by directly processing the timing data from an equal-size array. Since arrays can generate pairs of clock and ephemeris-free timing combinations that are no longer affected by correlated noises, we implement with them the cross-correlation statistic to search for an isotropic stochastic gravitational wave background. We find the resulting optimal signal-to-noise ratio to be more than one order of magnitude larger than that obtainable by correlating pairs of timing data from arrays of equal size.

A 0.18 μm biosensor front-end based on 1/f noise, distortion cancelation and chopper stabilization techniques.

Science.gov (United States)

Balasubramanian, Viswanathan; Ruedi, Pierre-Francois; Temiz, Yuksel; Ferretti, Anna; Guiducci, Carlotta; Enz

2013-10-01

This paper presents a novel sensor front-end circuit that addresses the issues of 1/f noise and distortion in a unique way by using canceling techniques. The proposed front-end is a fully differential transimpedance amplifier (TIA) targeted for current mode electrochemical biosensing applications. In this paper, we discuss the architecture of this canceling based front-end and the optimization methods followed for achieving low noise, low distortion performance at minimum current consumption are presented. To validate the employed canceling based front-end, it has been realized in a 0.18 μm CMOS process and the characterization results are presented. The front-end has also been tested as part of a complete wireless sensing system and the cyclic voltammetry (CV) test results from electrochemical sensors are provided. Overall current consumption in the front-end is 50 μA while operating on a 1.8 V supply.

FPGA implementation of ICA algorithm for blind signal separation and adaptive noise canceling.

Science.gov (United States)

Kim, Chang-Min; Park, Hyung-Min; Kim, Taesu; Choi, Yoon-Kyung; Lee, Soo-Young

2003-01-01

An field programmable gate array (FPGA) implementation of independent component analysis (ICA) algorithm is reported for blind signal separation (BSS) and adaptive noise canceling (ANC) in real time. In order to provide enormous computing power for ICA-based algorithms with multipath reverberation, a special digital processor is designed and implemented in FPGA. The chip design fully utilizes modular concept and several chips may be put together for complex applications with a large number of noise sources. Experimental results with a fabricated test board are reported for ANC only, BSS only, and simultaneous ANC/BSS, which demonstrates successful speech enhancement in real environments in real time.

The effect of losses on the quantum-noise cancellation in the SU(1,1) interferometer

International Nuclear Information System (INIS)

Xin, Jun; Wang, Hailong; Jing, Jietai

2016-01-01

Quantum-noise cancellation (QNC) is an effective method to control the noise of the quantum system, which reduces or even eliminates the noise of the quantum systems by utilizing destructive interference in the quantum system. However, QNC can be extremely dependent on the losses inside the system. In this letter, we experimentally and theoretically study how the losses can affect the QNC in the SU(1,1) interferometer. We find that losses in the different arms inside the SU(1,1) interferometer can have different effects on the QNC in the output fields from the SU(1,1) interferometer. And the QNC in the SU(1,1) interferometer can almost be insensitive to the losses in some cases. Our findings may find its potential applications in the quantum noise control.

The effect of losses on the quantum-noise cancellation in the SU(1,1) interferometer

Energy Technology Data Exchange (ETDEWEB)

Xin, Jun; Wang, Hailong [State Key Laboratory of Precision Spectroscopy, School of Physics and Materials Science, East China Normal University, Shanghai 200062 (China); Jing, Jietai, E-mail: jtjing@phy.ecnu.edu.cn [State Key Laboratory of Precision Spectroscopy, School of Physics and Materials Science, East China Normal University, Shanghai 200062 (China); Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006 (China)

2016-08-01

Quantum-noise cancellation (QNC) is an effective method to control the noise of the quantum system, which reduces or even eliminates the noise of the quantum systems by utilizing destructive interference in the quantum system. However, QNC can be extremely dependent on the losses inside the system. In this letter, we experimentally and theoretically study how the losses can affect the QNC in the SU(1,1) interferometer. We find that losses in the different arms inside the SU(1,1) interferometer can have different effects on the QNC in the output fields from the SU(1,1) interferometer. And the QNC in the SU(1,1) interferometer can almost be insensitive to the losses in some cases. Our findings may find its potential applications in the quantum noise control.

Fully integrated low-noise readout circuit with automatic offset cancellation loop for capacitive microsensors.

Science.gov (United States)

Song, Haryong; Park, Yunjong; Kim, Hyungseup; Cho, Dong-Il Dan; Ko, Hyoungho

2015-10-14

Capacitive sensing schemes are widely used for various microsensors; however, such microsensors suffer from severe parasitic capacitance problems. This paper presents a fully integrated low-noise readout circuit with automatic offset cancellation loop (AOCL) for capacitive microsensors. The output offsets of the capacitive sensing chain due to the parasitic capacitances and process variations are automatically removed using AOCL. The AOCL generates electrically equivalent offset capacitance and enables charge-domain fine calibration using a 10-bit R-2R digital-to-analog converter, charge-transfer switches, and a charge-storing capacitor. The AOCL cancels the unwanted offset by binary-search algorithm based on 10-bit successive approximation register (SAR) logic. The chip is implemented using 0.18 μm complementary metal-oxide-semiconductor (CMOS) process with an active area of 1.76 mm². The power consumption is 220 μW with 3.3 V supply. The input parasitic capacitances within the range of -250 fF to 250 fF can be cancelled out automatically, and the required calibration time is lower than 10 ms.

Fully Integrated Low-Noise Readout Circuit with Automatic Offset Cancellation Loop for Capacitive Microsensors

Directory of Open Access Journals (Sweden)

Haryong Song

2015-10-01

Full Text Available Capacitive sensing schemes are widely used for various microsensors; however, such microsensors suffer from severe parasitic capacitance problems. This paper presents a fully integrated low-noise readout circuit with automatic offset cancellation loop (AOCL for capacitive microsensors. The output offsets of the capacitive sensing chain due to the parasitic capacitances and process variations are automatically removed using AOCL. The AOCL generates electrically equivalent offset capacitance and enables charge-domain fine calibration using a 10-bit R-2R digital-to-analog converter, charge-transfer switches, and a charge-storing capacitor. The AOCL cancels the unwanted offset by binary-search algorithm based on 10-bit successive approximation register (SAR logic. The chip is implemented using 0.18 μm complementary metal-oxide-semiconductor (CMOS process with an active area of 1.76 mm2. The power consumption is 220 μW with 3.3 V supply. The input parasitic capacitances within the range of −250 fF to 250 fF can be cancelled out automatically, and the required calibration time is lower than 10 ms.

A 380pW Dual Mode Optical Wake-up Receiver with Ambient Noise Cancellation.

Science.gov (United States)

Lim, Wootaek; Jang, Taekwang; Lee, Inhee; Kim, Hun-Seok; Sylvester, Dennis; Blaauw, David

2016-06-01

We present a sub-nW optical wake-up receiver for wireless sensor nodes. The wake-up receiver supports dual mode operation for both ultra-low standby power and high data rates, while canceling ambient in-band noise. In 0.18µm CMOS the receiver consumes 380pW in always-on wake-up mode and 28.1µW in fast RX mode at 250kbps.

Helicopter Flight Procedures for Community Noise Reduction

Science.gov (United States)

Greenwood, Eric

2017-01-01

A computationally efficient, semiempirical noise model suitable for maneuvering flight noise prediction is used to evaluate the community noise impact of practical variations on several helicopter flight procedures typical of normal operations. Turns, "quick-stops," approaches, climbs, and combinations of these maneuvers are assessed. Relatively small variations in flight procedures are shown to cause significant changes to Sound Exposure Levels over a wide area. Guidelines are developed for helicopter pilots intended to provide effective strategies for reducing the negative effects of helicopter noise on the community. Finally, direct optimization of flight trajectories is conducted to identify low noise optimal flight procedures and quantify the magnitude of community noise reductions that can be obtained through tailored helicopter flight procedures. Physically realizable optimal turns and approaches are identified that achieve global noise reductions of as much as 10 dBA Sound Exposure Level.

Adaptive cancellation of motion artifact in wearable biosensors.

Science.gov (United States)

Yousefi, Rasoul; Nourani, Mehrdad; Panahi, Issa

2012-01-01

The performance of wearable biosensors is highly influenced by motion artifact. In this paper, a model is proposed for analysis of motion artifact in wearable photoplethysmography (PPG) sensors. Using this model, we proposed a robust real-time technique to estimate fundamental frequency and generate a noise reference signal. A Least Mean Square (LMS) adaptive noise canceler is then designed and validated using our synthetic noise generator. The analysis and results on proposed technique for noise cancellation shows promising performance.

A compressed sensing based method with support refinement for impulse noise cancelation in DSL

KAUST Repository

Quadeer, Ahmed Abdul

2013-06-01

This paper presents a compressed sensing based method to suppress impulse noise in digital subscriber line (DSL). The proposed algorithm exploits the sparse nature of the impulse noise and utilizes the carriers, already available in all practical DSL systems, for its estimation and cancelation. Specifically, compressed sensing is used for a coarse estimate of the impulse position, an a priori information based maximum aposteriori probability (MAP) metric for its refinement, followed by least squares (LS) or minimum mean square error (MMSE) estimation for estimating the impulse amplitudes. Simulation results show that the proposed scheme achieves higher rate as compared to other known sparse estimation algorithms in literature. The paper also demonstrates the superior performance of the proposed scheme compared to the ITU-T G992.3 standard that utilizes RS-coding for impulse noise refinement in DSL signals. © 2013 IEEE.

75 FR 39820 - Procedures for Abatement of Highway Traffic Noise and Construction Noise

Science.gov (United States)

2010-07-13

...-2008-0114] RIN 2125-AF26 Procedures for Abatement of Highway Traffic Noise and Construction Noise... the Federal regulations on the Procedures for Abatement of Highway Traffic Noise and Construction Noise. The final rule clarifies and adds definitions, the applicability of this regulation, certain...

dc SQUID electronics based on adaptive noise cancellation and a high open-loop gain controller

International Nuclear Information System (INIS)

Seppae, H.

1992-01-01

A low-noise SQUID readout electronics with a high slew rate and an automatic gain control feature has been developed. Flux noise levels of 5x10 -7 Φ 0 /√Hz at 1 kHz and 2x10 -6 Φ 0 /√Hz at 1 Hz have been measured with this readout scheme. The system tolerates sinusoidal disturbances having amplitudes up to 140 Φ 0 at 1 kHz without loosing lock. The electronics utilizes a cooled GaAs FET to control the cancellation of the voltage noise of the room temperature amplifier, a PI 3/2 controller to provide a high open-loop gain at low frequencies, and a square-wave flux and offset voltage modulation to enable automatic control of the noise reduction. The cutoff frequency of the flux-locked-loop is 300 kHz and the feedback gain is more than 130 dB at 10 Hz. (orig.)

Beat Noise Cancellation in 2-D Optical Code-Division Multiple-Access Systems Using Optical Hard-Limiter Array

Science.gov (United States)

Dang, Ngoc T.; Pham, Anh T.; Cheng, Zixue

We analyze the beat noise cancellation in two-dimensional optical code-division multiple-access (2-D OCDMA) systems using an optical hard-limiter (OHL) array. The Gaussian shape of optical pulse is assumed and the impact of pulse propagation is considered. We also take into account the receiver noise and multiple access interference (MAI) in the analysis. The numerical results show that, when OHL array is employed, the system performance is greatly improved compared with the cases without OHL array. Also, parameters needed for practical system design are comprehensively analyzed.

Non-linear signal response functions and their effects on the statistical and noise cancellation properties of isotope ratio measurements by multi-collector plasma mass spectrometry

International Nuclear Information System (INIS)

Doherty, W.

2013-01-01

A nebulizer-centric response function model of the analytical inductively coupled argon plasma ion source was used to investigate the statistical frequency distributions and noise reduction factors of simultaneously measured flicker noise limited isotope ion signals and their ratios. The response function model was extended by assuming i) a single gaussian distributed random noise source (nebulizer gas pressure fluctuations) and ii) the isotope ion signal response is a parabolic function of the nebulizer gas pressure. Model calculations of ion signal and signal ratio histograms were obtained by applying the statistical method of translation to the non-linear response function model of the plasma. Histograms of Ni, Cu, Pr, Tl and Pb isotope ion signals measured using a multi-collector plasma mass spectrometer were, without exception, negative skew. Histograms of the corresponding isotope ratios of Ni, Cu, Tl and Pb were either positive or negative skew. There was a complete agreement between the measured and model calculated histogram skew properties. The nebulizer-centric response function model was also used to investigate the effect of non-linear response functions on the effectiveness of noise cancellation by signal division. An alternative noise correction procedure suitable for parabolic signal response functions was derived and applied to measurements of isotope ratios of Cu, Ni, Pb and Tl. The largest noise reduction factors were always obtained when the non-linearity of the response functions was taken into account by the isotope ratio calculation. Possible applications of the nebulizer-centric response function model to other types of analytical instrumentation, large amplitude signal noise sources (e.g., lasers, pumped nebulizers) and analytical error in isotope ratio measurements by multi-collector plasma mass spectrometry are discussed. - Highlights: ► Isotope ion signal noise is modelled as a parabolic transform of a gaussian variable. ► Flicker

Interpixel crosstalk cancellation on holographic memory

Science.gov (United States)

Ishii, Toshiki; Fujimura, Ryushi

2017-09-01

In holographic memory systems, there have been no practical techniques to minimize interpixel crosstalk thus far. We developed an interpixel crosstalk cancellation technique using a checkerboard phase pattern with a phase difference of π/2, which can decrease the size of the spatial filter along the Fourier plane with the signal-to-noise ratio (SNR) kept high. This interpixel crosstalk cancellation technique is simple because it requires only one phase plate in the signal beam path. We verified the effect of such a cancellation technique by simulation. The improvement of SNR is maximized to 6.5 dB when the filter size specified in the Nyquist areal ratio is approximately 1.05 in ideal optical systems with no other fixed noise. The proposed technique can improve SNR by 0.85 in an assumed monocular architecture at an actual noise intensity. This improvement of SNR is very useful for realizing high-density recording or enhancing system robustness.

A wideband LNA employing gate-inductive-peaking and noise-canceling techniques in 0.18 μm CMOS

International Nuclear Information System (INIS)

Bao Kuan; Fan Xiangning; Li Wei; Zhang Li; Wang Zhigong

2012-01-01

This paper presents a wideband low noise amplifier (LNA) for multi-standard radio applications. The low noise characteristic is achieved by the noise-canceling technique while the bandwidth is enhanced by gate-inductive-peaking technique. High-frequency noise performance is consequently improved by the flattened gain over the entire operating frequency band. Fabricated in 0.18 μm CMOS process, the LNA achieves 2.5 GHz of −3 dB bandwidth and 16 dB of gain. The gain variation is within ±0.8 dB from 300 MHz to 2.2 GHz. The measured noise figure (NF) and average IIP3 are 3.4 dB and −2 dBm, respectively. The proposed LNA occupies 0.39 mm 2 core chip area. Operating at 1.8 V, the LNA drains a current of 11.7 mA. (semiconductor integrated circuits)

A 0.18 μm CMOS inductorless complementary-noise-canceling-LNA for TV tuner applications

International Nuclear Information System (INIS)

Yuan Haiquan; Lin Fujiang; Fu Zhongqian; Huang Lu

2010-01-01

This paper presents an inductorless complementary-noise-canceling LNA (CNCLNA) for TV tuners. The CNCLNA exploits single-to-differential topology, which consists of a common gate stage and a common source stage. The complementary topology can save power and improve the noise figure. Linearity is also enhanced by employing a multiple gated transistors technique. The chip is implemented in SMIC 0.18 μm CMOS technology. Measurement shows that the proposed CNCLNA achieves 13.5-16 dB voltage gain from 50 to 860 MHz, the noise figure is below 4.5 dB and has a minimum value of 2.9 dB, and the best P 1dB is -7.5 dBm at 860 MHz. The core consumes 6 mA current with a supply voltage of 1.8 V, while the core area is only 0.2 x 0.2 mm 2 . (semiconductor integrated circuits)

The effect on recognition memory of noise cancelling headphones in a noisy environment with native and nonnative speakers

Directory of Open Access Journals (Sweden)

Brett R C Molesworth

2014-01-01

Full Text Available Noise has the potential to impair cognitive performance. For nonnative speakers, the effect of noise on performance is more severe than their native counterparts. What remains unknown is the effectiveness of countermeasures such as noise attenuating devices in such circumstances. Therefore, the main aim of the present research was to examine the effectiveness of active noise attenuating countermeasures in the presence of simulated aircraft noise for both native and nonnative English speakers. Thirty-two participants, half native English speakers and half native German speakers completed four recognition (cued recall tasks presented in English under four different audio conditions, all in the presence of simulated aircraft noise. The results of the research indicated that in simulated aircraft noise at 65 dB(A, performance of nonnative English speakers was poorer than for native English speakers. The beneficial effects of noise cancelling headphones in improving the signal to noise ratio led to an improved performance for nonnative speakers. These results have particular importance for organizations operating in a safety-critical environment such as aviation.

Recognition of Voice Commands by Multisource ASR and Noise Cancellation in a Smart Home Environment

OpenAIRE

Vacher , Michel; Lecouteux , Benjamin; Portet , François

2012-01-01

International audience; In this paper, we present a multisource ASR system to detect home automation orders in various everyday listening conditions in a realistic home. The system is based on a state of the art echo cancellation stage that feeds recently introduced ASR techniques. The evaluation was conducted on a realistic noisy data set acquired in a smart home where a microphone was placed near the noise source and several other microphones were placed in different rooms. This distant spe...

Evaluation of State-of-the-Art Acoustic Feedback Cancellation Systems for Hearing Aids

DEFF Research Database (Denmark)

Guo, Meng; Jensen, Søren Holdt; Jensen, Jesper

2013-01-01

This research evaluates four state-of-the-art acoustic feedback cancellation systems in hearing aids in terms of the cancellation performance, sound quality degradation, and computational complexity. The authors compared a traditional full-band system to a system with a prediction error method...... in a full band, a subband system, a subband system with frequency shifting, and a recently proposed subband system with a novel probe noise deployment. All systems outperformed the traditional full-band system in cancellation performance, especially the subband system with probe noise is most effective...... for cancellation. However, in all cases there was a trade-off between performance and computational cost. With a 3-times increase in computation load, the probe noise based cancellation system can be realized that functions even in the most challenging feedback situation....

Reducing the Effects of Background Noise during Auditory Functional Magnetic Resonance Imaging of Speech Processing: Qualitative and Quantitative Comparisons between Two Image Acquisition Schemes and Noise Cancellation

Science.gov (United States)

Blackman, Graham A.; Hall, Deborah A.

2011-01-01

Purpose: The intense sound generated during functional magnetic resonance imaging (fMRI) complicates studies of speech and hearing. This experiment evaluated the benefits of using active noise cancellation (ANC), which attenuates the level of the scanner sound at the participant's ear by up to 35 dB around the peak at 600 Hz. Method: Speech and…

Intensity noise cancellation in solid-state laser at 1.5  μm using SHG depletion as a buffer reservoir.

Science.gov (United States)

Audo, Kevin; Alouini, Mehdi

2018-03-01

An absorption mechanism based on second-harmonic generation (SHG) is successfully implemented as a buffer reservoir in a solid-state Er,Yb:Glass laser emitting at the telecom wavelength. We show that a slight absorption mechanism based on SHG rate conversion of 0.016% using a beta barium borate crystal enables the canceling out of the excess intensity noise at the relaxation oscillation frequency, i.e., 35 dB reduction, as well as canceling the amplified spontaneous emission beating at the free spectral range resonances of the laser lying in the gigahertz range. Laser robustness is discussed.

Wiener variable step size and gradient spectral variance smoothing for double-talk-robust acoustic echo cancellation and acoustic feedback cancellation

DEFF Research Database (Denmark)

Gil-Cacho, Jose M.; Van Waterschoot, Toon; Moonen, Marc

2014-01-01

Double-talk (DT)-robust acoustic echo cancellation (AEC) and acoustic feedback cancellation (AFC) are needed in speech communication systems, e.g., in hands-free communication systems and hearing aids. In this paper, we derive a practical and computationally efficient algorithm based...... model and in colored non-stationary noise....

A procedure for noise uncoupling in laser interferometry

CERN Document Server

Barone, F; Rosa, R D; Eleuteri, A; Milano, L; Qipiani, K

2002-01-01

A numerical procedure for noise recognition and uncoupling is described. The procedure is applied to a Michelson interferometer and is effective in seismic and acoustic noise uncoupling from the output signal of the interferometer. Due to the low data flow coming from the instrumentation this uncoupling can be performed in real time and it is useful as a data quality procedure for interferometer data output.

A Microwave Photonic Interference Canceller: Architectures, Systems, and Integration

Science.gov (United States)

Chang, Matthew P.

This thesis is a comprehensive portfolio of work on a Microwave Photonic Self-Interference Canceller (MPC), a specialized optical system designed to eliminate interference from radio-frequency (RF) receivers. The novelty and value of the microwave photonic system lies in its ability to operate over bandwidths and frequencies that are orders of magnitude larger than what is possible using existing RF technology. The work begins, in 2012, with a discrete fiber-optic microwave photonic canceller, which prior work had demonstrated as a proof-of-concept, and culminates, in 2017, with the first ever monolithically integrated microwave photonic canceller. With an eye towards practical implementation, the thesis establishes novelty through three major project thrusts. (Fig. 1): (1) Extensive RF and system analysis to develop a full understanding of how, and through what mechanisms, MPCs affect an RF receiver. The first investigations of how a microwave photonic canceller performs in an actual wireless environment and a digital radio are also presented. (2) New architectures to improve the performance and functionality of MPCs, based on the analysis performed in Thrust 1. A novel balanced microwave photonic canceller architecture is developed and experimentally demonstrated. The balanced architecture shows significant improvements in link gain, noise figure, and dynamic range. Its main advantage is its ability to suppress common-mode noise and reduce noise figure by increasing the optical power. (3) Monolithic integration of the microwave photonic canceller into a photonic integrated circuit. This thrust presents the progression of integrating individual discrete devices into their semiconductor equivalent, as well as a full functional and RF analysis of the first ever integrated microwave photonic canceller.

Reduced Pain and Anxiety with Music and Noise-Canceling Headphones During Shockwave Lithotripsy.

Science.gov (United States)

Karalar, Mustafa; Keles, Ibrahim; Doğantekin, Engin; Kahveci, Orhan Kemal; Sarici, Hasmet

2016-06-01

We assessed the effects of music and noise-canceling headphones (NCHs) on perceived patient pain and anxiety from extracorporeal shockwave lithotripsy (SWL). Patients with renal calculi scheduled for SWL were prospectively enrolled. All 89 patients between the ages of 19 and 80 years were informed about this study and then randomized into three groups: Group 1 (controls), no headphones and music; Group 2, music with NCHs (patients listened to Turkish classical music with NCHs during SWL); and Group 3, music with non-NCHs (patients listened to Turkish classical music with non-NCHs during SWL). Hemodynamic and respiratory parameters were recorded before and just after the SWL session. All patient visual analog scale (VAS) and State-Trait Anxiety Inventory (STAI) scores were recorded just after the SWL procedure. There were significant differences in VAS scores among the groups (5.1, 3.6, and 4.5, respectively, p < 0.001), including between Groups 2 and 3 (p = 0.018). There were also significant differences in STAI-State anxiety scores among the groups (43.1, 33.5, and 38.9, respectively, p = 0.001), including between Groups 2 and 3 (p = 0.04). Music therapy during SWL reduced pain and anxiety. Music therapy with NCHs was more effective for pain and anxiety reduction. To reduce pain and anxiety, nonpharmacologic therapies such as music therapy with NCHs during SWL should be investigated further and used routinely.

Adaptive HIFU noise cancellation for simultaneous therapy and imaging using an integrated HIFU/imaging transducer.

Science.gov (United States)

Jeong, Jong Seob; Cannata, Jonathan Matthew; Shung, K Kirk

2010-04-07

It was previously demonstrated that it is feasible to simultaneously perform ultrasound therapy and imaging of a coagulated lesion during treatment with an integrated transducer that is capable of high intensity focused ultrasound (HIFU) and B-mode ultrasound imaging. It was found that coded excitation and fixed notch filtering upon reception could significantly reduce interference caused by the therapeutic transducer. During HIFU sonication, the imaging signal generated with coded excitation and fixed notch filtering had a range side-lobe level of less than -40 dB, while traditional short-pulse excitation and fixed notch filtering produced a range side-lobe level of -20 dB. The shortcoming is, however, that relatively complicated electronics may be needed to utilize coded excitation in an array imaging system. It is for this reason that in this paper an adaptive noise canceling technique is proposed to improve image quality by minimizing not only the therapeutic interference, but also the remnant side-lobe 'ripples' when using the traditional short-pulse excitation. The performance of this technique was verified through simulation and experiments using a prototype integrated HIFU/imaging transducer. Although it is known that the remnant ripples are related to the notch attenuation value of the fixed notch filter, in reality, it is difficult to find the optimal notch attenuation value due to the change in targets or the media resulted from motion or different acoustic properties even during one sonication pulse. In contrast, the proposed adaptive noise canceling technique is capable of optimally minimizing both the therapeutic interference and residual ripples without such constraints. The prototype integrated HIFU/imaging transducer is composed of three rectangular elements. The 6 MHz center element is used for imaging and the outer two identical 4 MHz elements work together to transmit the HIFU beam. Two HIFU elements of 14.4 mm x 20.0 mm dimensions could

Adaptive HIFU noise cancellation for simultaneous therapy and imaging using an integrated HIFU/imaging transducer

International Nuclear Information System (INIS)

Jeong, Jong Seob; Cannata, Jonathan Matthew; Shung, K Kirk

2010-01-01

It was previously demonstrated that it is feasible to simultaneously perform ultrasound therapy and imaging of a coagulated lesion during treatment with an integrated transducer that is capable of high intensity focused ultrasound (HIFU) and B-mode ultrasound imaging. It was found that coded excitation and fixed notch filtering upon reception could significantly reduce interference caused by the therapeutic transducer. During HIFU sonication, the imaging signal generated with coded excitation and fixed notch filtering had a range side-lobe level of less than -40 dB, while traditional short-pulse excitation and fixed notch filtering produced a range side-lobe level of -20 dB. The shortcoming is, however, that relatively complicated electronics may be needed to utilize coded excitation in an array imaging system. It is for this reason that in this paper an adaptive noise canceling technique is proposed to improve image quality by minimizing not only the therapeutic interference, but also the remnant side-lobe 'ripples' when using the traditional short-pulse excitation. The performance of this technique was verified through simulation and experiments using a prototype integrated HIFU/imaging transducer. Although it is known that the remnant ripples are related to the notch attenuation value of the fixed notch filter, in reality, it is difficult to find the optimal notch attenuation value due to the change in targets or the media resulted from motion or different acoustic properties even during one sonication pulse. In contrast, the proposed adaptive noise canceling technique is capable of optimally minimizing both the therapeutic interference and residual ripples without such constraints. The prototype integrated HIFU/imaging transducer is composed of three rectangular elements. The 6 MHz center element is used for imaging and the outer two identical 4 MHz elements work together to transmit the HIFU beam. Two HIFU elements of 14.4 mm x 20.0 mm dimensions could

Wideband Low Noise Amplifiers Exploiting Thermal Noise Cancellation

NARCIS (Netherlands)

Bruccoleri, F.; Klumperink, Eric A.M.; Nauta, Bram

2005-01-01

Low Noise Amplifiers (LNAs) are commonly used to amplify signals that are too weak for direct processing for example in radio or cable receivers. Traditionally, low noise amplifiers are implemented via tuned amplifiers, exploiting inductors and capacitors in resonating LC-circuits. This can render

An Embedded, Eight Channel, Noise Canceling, Wireless, Wearable sEMG Data Acquisition System With Adaptive Muscle Contraction Detection.

Science.gov (United States)

Ergeneci, Mert; Gokcesu, Kaan; Ertan, Erhan; Kosmas, Panagiotis

2018-02-01

Wearable technology has gained increasing popularity in the applications of healthcare, sports science, and biomedical engineering in recent years. Because of its convenient nature, the wearable technology is particularly useful in the acquisition of the physiological signals. Specifically, the (surface electromyography) sEMG systems, which measure the muscle activation potentials, greatly benefit from this technology in both clinical and industrial applications. However, the current wearable sEMG systems have several drawbacks including inefficient noise cancellation, insufficient measurement quality, and difficult integration to customized applications. Additionally, none of these sEMG data acquisition systems can detect sEMG signals (i.e., contractions), which provides a valuable environment for further studies such as human machine interaction, gesture recognition, and fatigue tracking. To this end, we introduce an embedded, eight channel, noise canceling, wireless, wearable sEMG data acquisition system with adaptive muscle contraction detection. Our design consists of two stages, which are the sEMG sensors and the multichannel data acquisition unit. For the first stage, we propose a low cost, dry, and active sEMG sensor that captures the muscle activation potentials, a data acquisition unit that evaluates these captured multichannel sEMG signals and transmits them to a user interface. In the data acquisition unit, the sEMG signals are processed through embedded, adaptive methods in order to reject the power line noise and detect the muscle contractions. Through extensive experiments, we demonstrate that our sEMG sensor outperforms a widely used commercially available product and our data acquisition system achieves 4.583 dB SNR gain with accuracy in the detection of the contractions.

Cancelled surgeries and payment by results in the English National Health Service.

Science.gov (United States)

McIntosh, Bryan; Cookson, Graham; Jones, Simon

2012-04-01

To model the frequency of 'last minute' cancellations of planned elective procedures in the English NHS with respect to the patient and provider factors that led to these cancellations. A dataset of 5,288,604 elective patients spell in the English NHS from January 1st, 2007 to December 31st, 2007 was extracted from the Hospital Episode Statistics. A binary dependent variable indicating whether or not a patient had a Health Resource Group coded as S22--'Planned elective procedure not carried out'--was modeled using a probit regression estimated via maximum likelihood including patient, case and hospital level covariates. Longer waiting times and being admitted on a Monday were associated with a greater rate of cancelled procedures. Male patients, patients from lower socio-economic groups and older patients had higher rates of cancelled procedures. There was significant variation in cancellation rates between hospitals; Foundation Trusts and private facilities had the lowest cancellation rates. Further research is needed on why Foundation Trusts exhibit lower cancellation rates. Hospitals with relatively high cancellation rates should be encouraged to tackle this problem. Further evidence is needed on whether hospitals are more likely to cancel operations where the procedure tariff is lower than the S22 tariff as this creates a perverse incentive to cancel. Understanding the underlying causes of why male, older and patients from lower socio-economic groups are more likely to have their operations cancelled is important to inform the appropriate policy response. This research suggests that interventions designed to reduce cancellation rates should be targeted to high-cancellation groups.

Time Delay Mechanical-noise Cancellation (TDMC) to Provide Order of Magnitude Improvements in Radio Science Observations

Science.gov (United States)

Atkinson, D. H.; Babuscia, A.; Lazio, J.; Asmar, S.

2017-12-01

Many Radio Science investigations, including the determinations of planetary masses, measurements of planetary atmospheres, studies of the solar wind, and solar system tests of relativistic gravity, rely heavily on precision Doppler tracking. Recent and currently proposed missions such as VERITAS, Bepi Colombo, Juno have shown that the largest error source in the precision Doppler tracking data is noise in the Doppler system. This noise is attributed to un-modeled motions of the ground antenna's phase center and is commonly referred to as "antenna mechanical noise." Attempting to reduce this mechanical noise has proven difficult since the deep space communications antennas utilize large steel structures that are already optimized for mechanical stability. Armstrong et al. (2008) have demonstrated the Time Delay Mechanical-noise Cancellation (TDMC) concept using Goldstone DSN antennas (70 m & 34 m) and the Cassinispacecraft to show that the mechanical noise of the 70 m antenna could be suppressed when two-way Doppler tracking from the 70 m antenna and the receive-only Doppler data from the smaller, stiffer 34 m antenna were combined with suitable delays. The proof-of-concept confirmed that the mechanical noise in the final Doppler observable was reduced to that of the stiffer, more stable antenna. Caltech's Owens Valley Radio Observatory (OVRO) near Bishop, CA now has six 10.4 m diameter antennas, a consequence of the closure of Combined Array for Research in Millimeter Astronomy (CARMA). In principle, a 10 m antenna can lead to an order-of-magnitude improvement for the mechanical noise correction, as the smaller dish offers better mechanical stability compared to a DSN 34-m antenna. These antennas also have existing Ka-band receiving systems, and preliminary discussions with the OVRO staff suggest that much of the existing signal path could be used for Radio Science observations.

A Small-Area Self-Biased Wideband CMOS Balun LNA with Noise Cancelling and Gain Enhancement

DEFF Research Database (Denmark)

Bruun, Erik; Andreani, Pietro; Custódio, J. R.

2010-01-01

In this paper we present a low-power and small-area balun LNA. The proposed inverter-based topology uses selfbiasing and noise cancelling, yielding a very robust LNA with a low NF. Comparing this circuit with a conventional inverterbased circuit, we obtain a ∼3 dB enhancement in voltage gain......, with improved robustness against PVT variations. Simulations results in a 130 nm CMOS technology show a 17.7dB voltage gain, nearly flat over a wide bandwidth (200MHz-1GHz), and an NF of approximately 4dB. The total power consumption is below 7.5 mW, with a very small die area of 0.007 mm2. All data...

A novel approach to background subtraction in contrast-enhanced dual-energy digital mammography with commercially available mammography devices: Noise minimization

International Nuclear Information System (INIS)

Contillo, Adriano; Di Domenico, Giovanni; Cardarelli, Paolo; Gambaccini, Mauro; Taibi, Angelo

2016-01-01

Purpose: Dual-energy image subtraction represents a useful tool to improve the detectability of small lesions, especially in dense breasts. A feature it shares with all x-ray imaging techniques is the appearance of fluctuations in the texture of the background, which can obscure the visibility of interesting details. The aim of the work is to investigate the main noise sources, in order to create a better performing subtraction mechanism. In particular, the structural noise cancellation was achieved by means of a suitable extension of the dual-energy algorithm. Methods: The effect of the cancellation procedure was tested on an analytical simulation of a target with varying structural composition. Subsequently, the subtraction algorithm was also applied to a set of actual radiographs of a breast phantom exhibiting a nonuniform background pattern. The background power spectra of the outcomes were computed and compared to the ones obtained from a standard subtraction algorithm. Results: The comparison between the standard and the proposed cancellations showed an overall suppression of the magnitudes of the spectra, as well as a flattening of the frequency dependence of the structural component of the noise. Conclusions: The proposed subtraction procedure provides an effective cancellation of the residual background fluctuations. When combined with the polychromatic correction already described in a companion publication, it results in a high performing dual-energy subtraction scheme for commercial mammography units.

A novel approach to background subtraction in contrast-enhanced dual-energy digital mammography with commercially available mammography devices: Noise minimization

Energy Technology Data Exchange (ETDEWEB)

Contillo, Adriano, E-mail: contillo@fe.infn.it; Di Domenico, Giovanni; Cardarelli, Paolo; Gambaccini, Mauro; Taibi, Angelo [Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Ferrara, Via Saragat 1, I-44122 Ferrara (Italy)

2016-06-15

Purpose: Dual-energy image subtraction represents a useful tool to improve the detectability of small lesions, especially in dense breasts. A feature it shares with all x-ray imaging techniques is the appearance of fluctuations in the texture of the background, which can obscure the visibility of interesting details. The aim of the work is to investigate the main noise sources, in order to create a better performing subtraction mechanism. In particular, the structural noise cancellation was achieved by means of a suitable extension of the dual-energy algorithm. Methods: The effect of the cancellation procedure was tested on an analytical simulation of a target with varying structural composition. Subsequently, the subtraction algorithm was also applied to a set of actual radiographs of a breast phantom exhibiting a nonuniform background pattern. The background power spectra of the outcomes were computed and compared to the ones obtained from a standard subtraction algorithm. Results: The comparison between the standard and the proposed cancellations showed an overall suppression of the magnitudes of the spectra, as well as a flattening of the frequency dependence of the structural component of the noise. Conclusions: The proposed subtraction procedure provides an effective cancellation of the residual background fluctuations. When combined with the polychromatic correction already described in a companion publication, it results in a high performing dual-energy subtraction scheme for commercial mammography units.

Linewidth-tolerant 10-Gbit/s 16-QAM transmission using a pilot-carrier based phase-noise cancelling technique.

Science.gov (United States)

Nakamura, Moriya; Kamio, Yukiyoshi; Miyazaki, Tetsuya

2008-07-07

We experimentally demonstrated linewidth-tolerant 10-Gbit/s (2.5-Gsymbol/s) 16-quadrature amplitude modulation (QAM) by using a distributed-feedback laser diode (DFB-LD) with a linewidth of 30 MHz. Error-free operation, a bit-error rate (BER) of noise canceling capability provided by a pilot-carrier and standard electronic pre-equalization to suppress inter-symbol interference (ISI) gave clear 16-QAM constellations and floor-less BER characteristics. We evaluated the BER characteristics by real-time measurement of six (three different thresholds for each I- and Q-component) symbol error rates (SERs) with simultaneous constellation observation.

47 CFR 80.335 - Procedures for canceling false distress alerts.

Science.gov (United States)

2010-10-01

... message to “All stations” giving the ship's name, call sign or registration number, and MMSI, and cancel... on 2182 kHz; and (4) Transmit a broadcast message to “All stations” giving the ship's name, call sign... name, call sign or registration number, and MMSI, and cancel the false distress alert frequency in each...

An adaptive noise cancelling system used for beam control at the Stanford Linear Accelerator Center

International Nuclear Information System (INIS)

Himel, T.; Allison, S.; Grossberg, P.; Hendrickson, L.; Sass, R.; Shoaee, H.

1993-06-01

The SLAC Linear Collider now has a total of twenty-four beam-steering feedback loops used to keep the electron and positron beams on their desired trajectories. Seven of these loops measure and control the same beam as it proceeds down the linac through the arcs to the final focus. Ideally by each loop should correct only for disturbances that occur between it and the immediate upstream loop. In fact, in the original system each loop corrected for all upstream disturbances. This resulted in undesirable over-correction and ringing. We added MIMO (Multiple Input Multiple Output) adaptive noise cancellers to separate the signal we wish to correct from disturbances further upstream. This adaptive control improved performance in the 1992 run

Day of Surgery Admission in Total Joint Arthroplasty: Why Are Surgeries Cancelled? An Analysis of 3195 Planned Procedures and 114 Cancellations

Directory of Open Access Journals (Sweden)

David M. Dalton

2016-01-01

Full Text Available Background. Day of surgery admission (DOSA is becoming standard practice as a means of reducing cost in total joint arthroplasty. Aims. The aim of our study was to audit the use of DOSA in a specialty hospital and identify reasons for cancellation. Methods. A retrospective study of patients presenting for hip or knee arthroplasty between 2008 and 2013 was performed. All patients were assessed at the preoperative assessment clinic (PAC. Results. Of 3195 patients deemed fit for surgery, 114 patients (3.5% had their surgery cancelled. Ninety-two cancellations (80% were due to the patient being deemed medically unsuitable for surgery by the anaesthetist. Cardiac disease was the most common reason for cancellation (n=27, followed by pulmonary disease (n=22. 77 patients (67.5% had their operation rescheduled and successfully performed in our institution at a later date. Conclusion. DOSA is associated with a low rate of cancellations on the day of surgery. Patients with cardiorespiratory comorbidities are at greatest risk of cancellation.

Active control of the noise

International Nuclear Information System (INIS)

Rodriguez V, Luis Alfonso; Lopez Q, Jose German

2001-01-01

The problems of acoustic noise are more and more preponderant in the measure in that the amount of equipment and industrial machinery is increased such as fans, transformers, compressors etc. the use of devices passive mechanics for the reduction of the noise is effective and very appreciated because its effects embrace a wide range of acoustic frequency. However, to low frequencies, such devices become too big and expensive besides that present a tendency to do not effective. The control of active noise, CAN, using the electronic generation anti-noise, constitutes an interesting solution to the problem because their operation principle allows achieving an appreciable reduction of the noise by means of the use of compact devices. The traditional techniques for the control of acoustic noise like barriers and silenced to attenuate it, are classified as passive and their works has been accepted as norm as for the treatment of problems of noise it refers. Such techniques are considered in general very effective in the attenuation of noise of wide band. However, for low frequency, the required passive structures are too big and expensive; also, their effectiveness diminishes flagrantly, that which makes them impractical in many applications. The active suppression is profiled like a practical alternative for the reduction of acoustic noise. The idea in the active treatment of the noise it contemplates the use of a device electro-acoustic, like a speaker for example that it cancels to the noise by the generation of sounds of Same width and of contrary phase (anti-noise). The cancellation phenomenon is carried out when the ant-noise combines acoustically with the noise, what is in the cancellation of both sounds. The effectiveness of the cancellation of the primary source of noise depends on the precision with which the width and the phase of the generated ant-noise are controlled. The active control of noise, ANC (activates noise control), it is being investigated for

Active noise cancellation of low frequency noise propagating in a duct

Directory of Open Access Journals (Sweden)

Farhad Forouharmajd

2012-01-01

Conclusions: With regard to the wide range of frequencies of different noise sources, having optimized circumstances in the duct, microphone location on the duct body or even the distance of the speakers may be important in signal processing, noise sampling and anti noise production.

Noise Depression of Parasitic Capacitance for Frequency Detection of Micromechanical Bulk Disk Resonator

DEFF Research Database (Denmark)

Tang, Meng; Cagliani, Alberto; Escouflaire, Marie

2010-01-01

the frequency noise of the system. A capacitor cancellation circuit is used to subtract the parasitic capacitor. Measurements are conducted before and after the cancellation, and results show that after cancellation, the anti resonance is suppressed and the frequency noise is decreased, thus decreasing...

Applications of digital processing for noise removal from plasma diagnostics

International Nuclear Information System (INIS)

Kane, R.J.; Candy, J.V.; Casper, T.A.

1985-01-01

The use of digital signal techniques for removal of noise components present in plasma diagnostic signals is discussed, particularly with reference to diamagnetic loop signals. These signals contain noise due to power supply ripple in addition to plasma characteristics. The application of noise canceling techniques, such as adaptive noise canceling and model-based estimation, will be discussed. The use of computer codes such as SIG is described. 19 refs., 5 figs

Controlling kilometre-scale interferometric detectors for gravitational wave astronomy: Active phase noise cancellation using EOMs

International Nuclear Information System (INIS)

Arnaud, N.; Balembois, L.; Bizouard, M.A.; Brisson, V.; Casanueva, J.; Cavalier, F.; Davier, M.; Frey, V.; Hello, P.; Huet, D.; Leroy, N.; Loriette, V.; Maksimovic, I.; Robinet, F.

2017-01-01

The second generation of Gravitational waves detectors are kilometric Michelson interferometers with additional recycling Fabry–Perot cavities on the arms and ​the addition of two more recycling cavities to enhance their sensitivity, with the particularity that all the mirrors are suspended. In order to control them a new technique, based on the use of auxiliary lasers, has been developed to bring the interferometer to its working point, with all the cavities on their resonance, in an adiabatic way. The implementation of this technique in Advanced Virgo is under preparation and the propagation of a stable laser through a 3-km optical fibre is one of the most problematic issues. A new technique of active phase noise cancellation based on the use of Electro Optical Modulators has been developed, and a first prototype has been successfully tested.

Controlling kilometre-scale interferometric detectors for gravitational wave astronomy: Active phase noise cancellation using EOMs

Science.gov (United States)

Arnaud, N.; Balembois, L.; Bizouard, M. A.; Brisson, V.; Casanueva, J.; Cavalier, F.; Davier, M.; Frey, V.; Hello, P.; Huet, D.; Leroy, N.; Loriette, V.; Maksimovic, I.; Robinet, F.

2017-02-01

The second generation of Gravitational waves detectors are kilometric Michelson interferometers with additional recycling Fabry-Perot cavities on the arms and ​the addition of two more recycling cavities to enhance their sensitivity, with the particularity that all the mirrors are suspended. In order to control them a new technique, based on the use of auxiliary lasers, has been developed to bring the interferometer to its working point, with all the cavities on their resonance, in an adiabatic way. The implementation of this technique in Advanced Virgo is under preparation and the propagation of a stable laser through a 3-km optical fibre is one of the most problematic issues. A new technique of active phase noise cancellation based on the use of Electro Optical Modulators has been developed, and a first prototype has been successfully tested.

Controlling kilometre-scale interferometric detectors for gravitational wave astronomy: Active phase noise cancellation using EOMs

Energy Technology Data Exchange (ETDEWEB)

Arnaud, N.; Balembois, L.; Bizouard, M.A.; Brisson, V. [LAL, Univ. Paris-Sud, IN2P3/CNRS, Univ. Paris-Saclay, Orsay (France); Casanueva, J., E-mail: casanuev@lal.in2p3.fr [LAL, Univ. Paris-Sud, IN2P3/CNRS, Univ. Paris-Saclay, Orsay (France); Cavalier, F.; Davier, M.; Frey, V.; Hello, P.; Huet, D.; Leroy, N. [LAL, Univ. Paris-Sud, IN2P3/CNRS, Univ. Paris-Saclay, Orsay (France); Loriette, V.; Maksimovic, I. [ESPCI, CNRS, F-75005 Paris (France); Robinet, F. [LAL, Univ. Paris-Sud, IN2P3/CNRS, Univ. Paris-Saclay, Orsay (France)

2017-02-11

The second generation of Gravitational waves detectors are kilometric Michelson interferometers with additional recycling Fabry–Perot cavities on the arms and ​the addition of two more recycling cavities to enhance their sensitivity, with the particularity that all the mirrors are suspended. In order to control them a new technique, based on the use of auxiliary lasers, has been developed to bring the interferometer to its working point, with all the cavities on their resonance, in an adiabatic way. The implementation of this technique in Advanced Virgo is under preparation and the propagation of a stable laser through a 3-km optical fibre is one of the most problematic issues. A new technique of active phase noise cancellation based on the use of Electro Optical Modulators has been developed, and a first prototype has been successfully tested.

Applications of adaptive filters in active noise control

Science.gov (United States)

Darlington, Paul

The active reduction of acoustic noise is achieved by the addition of a cancelling acoustic signal to the unwanted sound. Successful definition of the cancelling signal amounts to a system identification problem. Recent advances in adaptive signal processing have allowed this problem to be tackled using adaptive filters, which offer significant advantages over conventional solutions. The extension of adaptive noise cancelling techniques, which were developed in the electrical signal conditioning context, to the control of acoustic systems is studied. An analysis is presented of the behavior of the Widrow-Hoff LMS adaptive noise canceller with a linear filter in its control loop. The active control of plane waves propagating axially in a hardwalled duct is used as a motivating model problem. The model problem also motivates the study of the effects of feedback around an LMS adaptive filter. An alternative stochastic gradient algorithm for controlling adaptive filters in the presence of feedback is presented.

Multiple-energy tissue-cancellation applications of a digital beam attenuator to chest radiography

International Nuclear Information System (INIS)

Dobbins, J.T. III.

1985-01-01

The digitally-formed primary beam attenuator (DBA) spatially modulates the x-ray fluence incident upon the patient to selectively attenuate regions of interest. The DBA attenuating mask is constructed from CeO 2 powder by a modified printing technique and uses image information from an initial low-dose exposure. Two tissue-cancellation imaging techniques are investigated with the DBA: (1) energy-dependent information is used to form a beam attenuator that attenuates specific tissues in the primary x-ray beam for tissue-cancelled film radiography; (2) the beam attenuator is used to improve image signal-to-noise and scattered radiation properties in traditional energy-subtraction tissue-cancellation imaging with digital detectors. The tissue-cancellation techniques in the primary x-ray beam were capable of adequately removing either soft-tissue or bone from the final compensated film radiograph when using a phantom with well defined soft-tissue and bone sections. However, when tried on an anthropomorphic chest phantom the results were adequate for cancellation of large soft tissue structures, but unsatisfactory for cancellation of bony structures such as the ribs, because of the limited spatial frequency content of the attenuating mask. The second technique (with digital detectors) showed improved uniformity of image signal-to-noise and a two-fold increase in soft-tissue nodule contrast due to improved scattered radiation properties. The tissue-cancelled images contained residual image contributions from the presence of the attenuating mask, but this residual may be correctable by future algorithms

Design and implementation of efficient low complexity biomedical artifact canceller for nano devices

Directory of Open Access Journals (Sweden)

Md Zia Ur RAHMAN

2016-07-01

Full Text Available In the current day scenario, with the rapid development of communication technology remote health care monitoring becomes as an intense research area. In remote health care monitoring, the primary aim is to facilitate the doctor with high resolution biomedical data. In order to cancel various artifacts in clinical environment in this paper we propose some efficient adaptive noise cancellation techniques. To obtain low computational complexity we combine clipping the data or error with Least Mean Square (LMS algorithm. This results sign regressor LMS (SRLMS, sign LMS (SLMS and sign LMS (SSLMS algorithms. Using these algorithms, we design Very-large-scale integration (VLSI architectures of various Biomedical Noise Cancellers (BNCs. In addition, the filtering capabilities of the proposed implementations are measured using real biomedical signals. Among the various BNCs tested, SRLMS based BNC is found to be better with reference to convergence speed, filtering capability and computational complexity. The main advantage of this technique is it needs only one multiplication to compute next weight. In this manner SRLMS based BNC is independent of filter length with reference to its computations. Whereas, the average signal to noise ratio achieved in the noise cancellation experiments are recorded as 7.1059dBs, 7.1776dBs, 6.2795dBs and 5.8847dBs for various BNCs based on LMS, SRLMS, SLMS and SSSLMS algorithms respectively. Based on the filtering characteristics, convergence and computational complexity, the proposed SRLMS based BNC architecture is well suited for nanotechnology applications.

Adaptive Beamforming Algorithms for Tow Ship Noise Canceling

NARCIS (Netherlands)

Robert, M.K.; Beerens, S.P.

2002-01-01

In towed array sonar, the directional noise originating from the tow ship, mainly machinery and hydrodynamic noise, often limits the sonar performance. When processed with classical beamforming techniques, loud tow ship noise induces high sidelobes that may hide detection of quiet targets in forward

An inverter-based capacitive trans-impedance amplifier readout with offset cancellation and temporal noise reduction for IR focal plane array

Science.gov (United States)

Chen, Hsin-Han; Hsieh, Chih-Cheng

2013-09-01

This paper presents a readout integrated circuit (ROIC) with inverter-based capacitive trans-impedance amplifier (CTIA) and pseudo-multiple sampling technique for infrared focal plane array (IRFPA). The proposed inverter-based CTIA with a coupling capacitor [1], executing auto-zeroing technique to cancel out the varied offset voltage from process variation, is used to substitute differential amplifier in conventional CTIA. The tunable detector bias is applied from a global external bias before exposure. This scheme not only retains stable detector bias voltage and signal injection efficiency, but also reduces the pixel area as well. Pseudo-multiple sampling technique [2] is adopted to reduce the temporal noise of readout circuit. The noise reduction performance is comparable to the conventional multiple sampling operation without need of longer readout time proportional to the number of samples. A CMOS image sensor chip with 55×65 pixel array has been fabricated in 0.18um CMOS technology. It achieves a 12um×12um pixel size, a frame rate of 72 fps, a power-per-pixel of 0.66uW/pixel, and a readout temporal noise of 1.06mVrms (16 times of pseudo-multiple sampling), respectively.

Two-step estimation procedures for inhomogeneous shot-noise Cox processes

DEFF Research Database (Denmark)

Prokesová, Michaela; Dvorák, Jirí; Jensen, Eva B. Vedel

In the present paper we develop several two-step estimation procedures for inhomogeneous shot-noise Cox processes. The intensity function is parametrized by the inhomogeneity parameters while the pair-correlation function is parametrized by the interaction parameters. The suggested procedures...

Elimination of noise peak for signal processing in Johnson noise thermometry development

International Nuclear Information System (INIS)

Hwang, I. G.; Moon, B. S.; Jeong, J. E.; Jeo, Y. H.; Kisner, Roger A.

2003-01-01

The internal and external noise is the most considering obstacle in development of Johnson Noise Thermometry system. This paper addresses an external noise elimination issue of the Johnson Noise Thermometry system which is underway of development in collaboration between KAERI and ORNL. Although internal random noise is canceled by Cross Power Spectral Density function, a continuous wave penetrating into the electronic circuit is eliminated by the difference of peaks between Johnson signal and external noise. The elimination logic using standard deviation of CPSD and energy leakage problem in discrete CPSD function are discussed in this paper

High phase noise tolerant pilot-tone-aided DP-QPSK optical communication systems

DEFF Research Database (Denmark)

Zhang, Xu; Pang, Xiaodan; Deng, Lei

2012-01-01

In this paper we experimentally demonstrate a novel, high phase-noise tolerant, optical dual polarization (DP) quadrature phase-shift keying (QPSK) communication system based on pilot-tone-aided phase noise cancellation (PNC) algorithm. Vertical cavity surface emitting lasers (VCSELs) with approx......In this paper we experimentally demonstrate a novel, high phase-noise tolerant, optical dual polarization (DP) quadrature phase-shift keying (QPSK) communication system based on pilot-tone-aided phase noise cancellation (PNC) algorithm. Vertical cavity surface emitting lasers (VCSELs...

A comparative evaluation of adaptive noise cancellation algorithms for minimizing motion artifacts in a forehead-mounted wearable pulse oximeter.

Science.gov (United States)

Comtois, Gary; Mendelson, Yitzhak; Ramuka, Piyush

2007-01-01

Wearable physiological monitoring using a pulse oximeter would enable field medics to monitor multiple injuries simultaneously, thereby prioritizing medical intervention when resources are limited. However, a primary factor limiting the accuracy of pulse oximetry is poor signal-to-noise ratio since photoplethysmographic (PPG) signals, from which arterial oxygen saturation (SpO2) and heart rate (HR) measurements are derived, are compromised by movement artifacts. This study was undertaken to quantify SpO2 and HR errors induced by certain motion artifacts utilizing accelerometry-based adaptive noise cancellation (ANC). Since the fingers are generally more vulnerable to motion artifacts, measurements were performed using a custom forehead-mounted wearable pulse oximeter developed for real-time remote physiological monitoring and triage applications. This study revealed that processing motion-corrupted PPG signals by least mean squares (LMS) and recursive least squares (RLS) algorithms can be effective to reduce SpO2 and HR errors during jogging, but the degree of improvement depends on filter order. Although both algorithms produced similar improvements, implementing the adaptive LMS algorithm is advantageous since it requires significantly less operations.

Beamforming design with proactive interference cancelation in MISO interference channels

Science.gov (United States)

Li, Yang; Tian, Yafei; Yang, Chenyang

2015-12-01

In this paper, we design coordinated beamforming at base stations (BSs) to facilitate interference cancelation at users in interference networks, where each BS is equipped with multiple antennas and each user is with a single antenna. By assuming that each user can select the best decoding strategy to mitigate the interference, either canceling the interference after decoding when it is strong or treating it as noise when it is weak, we optimize the beamforming vectors that maximize the sum rate for the networks under different interference scenarios and find the solutions of beamforming with closed-form expressions. The inherent design principles are then analyzed, and the performance gain over passive interference cancelation is demonstrated through simulations in heterogeneous cellular networks.

Reduction of environmental MHz noise for SQUID application

Energy Technology Data Exchange (ETDEWEB)

Araya, T. [Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531 (Japan)]. E-mail: araya@sup.ee.es.osaka-u.ac.jp; Kitamura, Y. [Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531 (Japan); Kamishiro, M. [Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531 (Japan); Sakuta, K. [Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531 (Japan); Itozaki, H. [Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531 (Japan)]. E-mail: itozaki@ee.es.osaka-u.ac.jp

2006-10-01

It is important to remove large environmental noise in measurement using SQUIDs without magnetic shielding. Active noise control (ANC) is an effective method to remove the environmental noise. The environmental noise has been reduced by the ANC system in the radio frequency region around MHz. The anti-phase waves of the environmental noise should be generated by this system. The ANC system including the phase and amplitude control circuit was developed to make the anti-phase waves in the MHz region. In this paper, sinusoidal waves with a MHz frequency were used as the environmental noise. When a coil antenna was used for a receiver antenna, this ANC system suppressed these sinusoidal waves to the white noise level about 40 dB. When we used a SQUID as a receiver antenna, we also cancelled sinusoidal waves to the white noise level by this system. This shows that the ANC system is useful to reduce an environmental noise when this ANC system is developed to cancel multi-frequency noise.

Reduction of environmental MHz noise for SQUID application

International Nuclear Information System (INIS)

Araya, T.; Kitamura, Y.; Kamishiro, M.; Sakuta, K.; Itozaki, H.

2006-01-01

It is important to remove large environmental noise in measurement using SQUIDs without magnetic shielding. Active noise control (ANC) is an effective method to remove the environmental noise. The environmental noise has been reduced by the ANC system in the radio frequency region around MHz. The anti-phase waves of the environmental noise should be generated by this system. The ANC system including the phase and amplitude control circuit was developed to make the anti-phase waves in the MHz region. In this paper, sinusoidal waves with a MHz frequency were used as the environmental noise. When a coil antenna was used for a receiver antenna, this ANC system suppressed these sinusoidal waves to the white noise level about 40 dB. When we used a SQUID as a receiver antenna, we also cancelled sinusoidal waves to the white noise level by this system. This shows that the ANC system is useful to reduce an environmental noise when this ANC system is developed to cancel multi-frequency noise

Active cancellation of probing in linear dipole phased array

CERN Document Server

Singh, Hema; Jha, Rakesh Mohan

2015-01-01

In this book, a modified improved LMS algorithm is employed for weight adaptation of dipole array for the generation of beam pattern in multiple signal environments. In phased arrays, the generation of adapted pattern according to the signal scenario requires an efficient adaptive algorithm. The antenna array is expected to maintain sufficient gain towards each of the desired source while at the same time suppress the probing sources. This cancels the signal transmission towards each of the hostile probing sources leading to active cancellation. In the book, the performance of dipole phased array is demonstrated in terms of fast convergence, output noise power and output signal-to-interference-and noise ratio. The mutual coupling effect and role of edge elements are taken into account. It is established that dipole array along with an efficient algorithm is able to maintain multilobe beamforming with accurate and deep nulls towards each probing source. This work has application to the active radar cross secti...

Experimental Validation Of An Innovative Procedure For The Rolling Noise Correction

Directory of Open Access Journals (Sweden)

Viscardi Massimo

2017-01-01

Full Text Available Among the wide contest of the train vehicles rolling noise evaluation, the aim of the paper is the development, implementation and experimental testing of a new method for roughness calculation according to FprCEN/TR 16891:2015 and the successive evaluation of the correction parameters of the measured rolling noise due to the presence of not compliant rail roughness. It is, in-fact, a very often operative condition, the execution of rolling noise tests over standard in-operation rails that are characterized by roughness profiles very different from standard one as those prescribed within the ISO 3095 procedure. Very often, this difference lead to the presence of an exceeding noise that needs to be evaluated and revised for a correct definition of the phenomena. Within the paper, the procedure implementation is presented and later on verified in operative experimental contest; forecasted and measured data are compared and successively commented.

49 CFR 40.267 - What problems always cause an alcohol test to be cancelled?

Science.gov (United States)

2010-10-01

... cancelled? 40.267 Section 40.267 Transportation Office of the Secretary of Transportation PROCEDURES FOR... always cause an alcohol test to be cancelled? As an employer, a BAT, or an STT, you must cancel an... the test was cancelled and must be treated as if the test never occurred. These problems are: (a) In...

Imperfect generalized transmit beamforming with co-channel interference cancelation

KAUST Repository

Radaydeh, Redha Mahmoud Mesleh

2010-10-01

The performance of a generalized single-stream transmit beamforming scheme employing receive co-channel interference -steering algorithms in slowly varying and flat fading channels is analyzed. The impact of imperfect prediction of channel state information (CSI) for the desired user spatially uncorrelated transmit channels is considered. Both dominant interference cancelation and adaptive arbitrary interference cancelation algorithms for closely spaced receive antennas are used. The impact of outdated statistical ordering of the interferers instantaneous powers on the effectiveness of dominant interference cancelation is investigated against the less complex adaptive arbitrary cancelation scheme. For the system models described above, new exact formulas for the statistics of combined signal-to-interference-plus-noise ratio (SINR) are derived, from which results for conventional maximum ratio transmission (MRT) and best transmit channel selection schemes can be deduced as limiting cases. The results presented herein can be used to obtain quantitative measure for various performance metrics, and in addition to investigate the performance-complexity tradeoff for different multiple-antenna system models. © 2010 IEEE.

Case review analysis of operating room decisions to cancel surgery.

Science.gov (United States)

Chang, Ju-Hsin; Chen, Ke-Wei; Chen, Kuen-Bao; Poon, Kin-Shing; Liu, Shih-Kai

2014-07-23

Cancellation of surgery close to scheduled time causes a waste of healthcare resources. The current study analyzes surgery cancellations occurring after the patient has been prepared for the operating room, in order to see whether improvements in the surgery planning process may reduce the number of cancellations. In a retrospective chart review of operating room surgery cancellations during the period from 2006 to 2011, cancellations were divided into the following categories: inadequate NPO; medical; surgical; system; airway; incomplete evaluation. The relative use of these reasons in relation to patient age and surgical department was then evaluated. Forty-one percent of cancellations were for other than medical reasons. Among these, 17.7% were due to incomplete evaluation, and 8.2% were due to family issues. Sixty seven percent of cancelled cases eventually received surgery. The relative use of individual reasons for cancellation varied with patient age and surgical department. The difference between cancellations before and after anesthesia was dependent on the causes of cancellation, but not age, sex, ASA status, or follow-up procedures required. Almost half of the cancellations were not due to medical reasons, and these cancellations could be reduced by better administrative and surgical planning and better communication with the patient and/or his family.

Adaptive Noise Canceling Menggunakan Algoritma Least Mean Square (Lms)

OpenAIRE

Nardiana, Anita; Sumaryono, Sari Sujoko

2011-01-01

Noise is inevitable in communication system. In some cases, noise can disturb signal. It is veryannoying as the received signal is jumbled with the noise itself. To reduce or remove noise, filter lowpass,highpass or bandpass can solve the problems, but this method cannot reach a maximum standard. One ofthe alternatives to solve the problem is by using adaptive filter. Adaptive algorithm frequently used is LeastMean Square (LMS) Algorithm which is compatible to Finite Impulse Response (FIR). T...

A Robust Approach For Acoustic Noise Suppression In Speech Using ANFIS

Science.gov (United States)

Martinek, Radek; Kelnar, Michal; Vanus, Jan; Bilik, Petr; Zidek, Jan

2015-11-01

The authors of this article deals with the implementation of a combination of techniques of the fuzzy system and artificial intelligence in the application area of non-linear noise and interference suppression. This structure used is called an Adaptive Neuro Fuzzy Inference System (ANFIS). This system finds practical use mainly in audio telephone (mobile) communication in a noisy environment (transport, production halls, sports matches, etc). Experimental methods based on the two-input adaptive noise cancellation concept was clearly outlined. Within the experiments carried out, the authors created, based on the ANFIS structure, a comprehensive system for adaptive suppression of unwanted background interference that occurs in audio communication and degrades the audio signal. The system designed has been tested on real voice signals. This article presents the investigation and comparison amongst three distinct approaches to noise cancellation in speech; they are LMS (least mean squares) and RLS (recursive least squares) adaptive filtering and ANFIS. A careful review of literatures indicated the importance of non-linear adaptive algorithms over linear ones in noise cancellation. It was concluded that the ANFIS approach had the overall best performance as it efficiently cancelled noise even in highly noise-degraded speech. Results were drawn from the successful experimentation, subjective-based tests were used to analyse their comparative performance while objective tests were used to validate them. Implementation of algorithms was experimentally carried out in Matlab to justify the claims and determine their relative performances.

Interference Canceller Based on Cycle-and-Add Property for Single User Detection in DS-CDMA

Science.gov (United States)

Hettiarachchi, Ranga; Yokoyama, Mitsuo; Uehara, Hideyuki; Ohira, Takashi

In this paper, performance of a novel interference cancellation technique for the single user detection in a direct-sequence code-division multiple access (DS-CDMA) system has been investigated. This new algorithm is based on the Cycle-and-Add property of PN (Pseudorandom Noise) sequences and can be applied for both synchronous and asynchronous systems. The proposed strategy provides a simple method that can delete interference signals one by one in spite of the power levels of interferences. Therefore, it is possible to overcome the near-far problem (NFP) in a successive manner without using transmit power control (TPC) techniques. The validity of the proposed procedure is corroborated by computer simulations in additive white Gaussian noise (AWGN) and frequency-nonselective fading channels. Performance results indicate that the proposed receiver outperforms the conventional receiver and, in many cases, it does so with a considerable gain.

Active Control of Fan Noise-Feasibility Study. Volume 2: Canceling Noise Source-Design of an Acoustic Plate Radiator Using Piezoceramic Actuators

Science.gov (United States)

Pla, F. G.; Rajiyah, H.

1995-01-01

The feasibility of using acoustic plate radiators powered by piezoceramic thin sheets as canceling sources for active control of aircraft engine fan noise is demonstrated. Analytical and numerical models of actuated beams and plates are developed and validated. An optimization study is performed to identify the optimum combination of design parameters that maximizes the plate volume velocity for a given resonance frequency. Fifteen plates with various plate and actuator sizes, thicknesses, and bonding layers were fabricated and tested using results from the optimization study. A maximum equivalent piston displacement of 0.39 mm was achieved with the optimized plate samples tested with only one actuator powered, corresponding to a plate deflection at the center of over 1 millimeter. This is very close to the deflection required for a full size engine application and represents a 160-fold improvement over previous work. Experimental results further show that performance is limited by the critical stress of the piezoceramic actuator and bonding layer rather than by the maximum moment available from the actuator. Design enhancements are described in detail that will lead to a flight-worthy acoustic plate radiator by minimizing actuator tensile stresses and reducing nonlinear effects. Finally, several adaptive tuning methods designed to increase the bandwidth of acoustic plate radiators are analyzed including passive, active, and semi-active approaches. The back chamber pressurization and volume variation methods are investigated experimentally and shown to be simple and effective ways to obtain substantial control over the resonance frequency of a plate radiator. This study shows that piezoceramic-based plate radiators can be a viable acoustic source for active control of aircraft engine fan noise.

Displacement-noise-free gravitational-wave detection with a single Fabry-Perot cavity: A toy model

International Nuclear Information System (INIS)

Tarabrin, Sergey P.; Vyatchanin, Sergey P.

2008-01-01

We propose a detuned Fabry-Perot cavity, pumped through both the mirrors, as a toy model of the gravitational-wave (GW) detector partially free from displacement noise of the test masses. It is demonstrated that the noise of cavity mirrors can be eliminated, but the one of lasers and detectors cannot. The isolation of the GW signal from displacement noise of the mirrors is achieved in a proper linear combination of the cavity output signals. The construction of such a linear combination is possible due to the difference between the reflected and transmitted output signals of detuned cavity. We demonstrate that in low-frequency region the obtained displacement-noise-free response signal is much stronger than the f gw 3 -limited sensitivity of displacement-noise-free interferometers recently proposed by S. Kawamura and Y. Chen. However, the loss of the resonant gain in the noise cancelation procedure results is the sensitivity limitation of our toy model by displacement noise of lasers and detectors

Wide-band CMOS low-noise amplifier exploiting thermal noise canceling

NARCIS (Netherlands)

Bruccoleri, F.; Klumperink, Eric A.M.; Nauta, Bram

Known elementary wide-band amplifiers suffer from a fundamental tradeoff between noise figure (NF) and source impedance matching, which limits the NF to values typically above 3 dB. Global negative feedback can be used to break this tradeoff, however, at the price of potential instability. In

49 CFR 40.199 - What problems always cause a drug test to be cancelled?

Science.gov (United States)

2010-10-01

... cancelled? 40.199 Section 40.199 Transportation Office of the Secretary of Transportation PROCEDURES FOR... cause a drug test to be cancelled? (a) As the MRO, when the laboratory discovers a “fatal flaw” during... specimen has been “Rejected for Testing” (with the reason stated). You must always cancel such a test. (b...

Noise-Canceling Helmet Audio System

Science.gov (United States)

Seibert, Marc A.; Culotta, Anthony J.

2007-01-01

A prototype helmet audio system has been developed to improve voice communication for the wearer in a noisy environment. The system was originally intended to be used in a space suit, wherein noise generated by airflow of the spacesuit life-support system can make it difficult for remote listeners to understand the astronaut s speech and can interfere with the astronaut s attempt to issue vocal commands to a voice-controlled robot. The system could be adapted to terrestrial use in helmets of protective suits that are typically worn in noisy settings: examples include biohazard, fire, rescue, and diving suits. The system (see figure) includes an array of microphones and small loudspeakers mounted at fixed positions in a helmet, amplifiers and signal-routing circuitry, and a commercial digital signal processor (DSP). Notwithstanding the fixed positions of the microphones and loudspeakers, the system can accommodate itself to any normal motion of the wearer s head within the helmet. The system operates in conjunction with a radio transceiver. An audio signal arriving via the transceiver intended to be heard by the wearer is adjusted in volume and otherwise conditioned and sent to the loudspeakers. The wearer s speech is collected by the microphones, the outputs of which are logically combined (phased) so as to form a microphone- array directional sensitivity pattern that discriminates in favor of sounds coming from vicinity of the wearer s mouth and against sounds coming from elsewhere. In the DSP, digitized samples of the microphone outputs are processed to filter out airflow noise and to eliminate feedback from the loudspeakers to the microphones. The resulting conditioned version of the wearer s speech signal is sent to the transceiver.

Using the effect of alcohol as a comparison to illustrate the detrimental effects of noise on performance

Directory of Open Access Journals (Sweden)

Brett R.C Molesworth

2013-01-01

Full Text Available The aim of the present research is to provide a user-friendly index of the relative impairment associated with noise in the aircraft cabin. As such, the relative effect of noise, at a level typical of an aircraft cabin was compared with varying levels of alcohol intoxication in the same subjects. Since the detrimental effect of noise is more pronounced on non-native speakers, both native English and non-native English speakers featured in the study. Noise cancelling headphones were also tested as a simple countermeasure to mitigate the effect of noise on performance. A total of 32 participants, half of which were non-native English speakers, completed a cued recall task in two alcohol conditions (blood alcohol concentration 0.05 and 0.10 and two audio conditions (audio played through the speaker and noise cancelling headphones. The results revealed that aircraft noise at 65 dB (A negatively affected performance to a level comparable to alcohol intoxication of 0.10. The results also supported previous research that reflects positively on the benefits of noise cancelling headphones in reducing the effects of noise on performance especially for non-native English speakers. These findings provide for personnel involved in the aviation industry, a user-friendly index of the relative impairment associated with noise in the aircraft cabin as compared with the effects of alcohol. They also highlight the benefits of a simple countermeasure such as noise cancelling headphones in mitigating some of the detrimental effects of noise on performance.

Analysing Self Interference Cancellation in Full Duplex Radios

DEFF Research Database (Denmark)

Mahmood, Nurul Huda; Shafique Ansari, Imran; Berardinelli, Gilberto

2016-01-01

Full duplex communication promises a theoretical $100\\%$ throughput gain by doubling the number of simultaneous transmissions. Such compelling gains are conditioned on perfect cancellation of the self interference power resulting from simultaneous transmission and reception. Generally, self...... interference power is modelled as a noise-like constant level interference floor. However, experimental validations have shown that the self interference power is in practice a random variable depending on a number of factors such as the surrounding wireless environment and the degree of interference...... cancellation. In this study, we derive an analytical model for the residual self interference power, and demonstrate various applications of the derived model in analysing the performance of a Full Duplex radio. In general, full duplex communication is found to provide only modest throughput gains over half...

Wideband Balun-LNA with Simultaneous Output Balancing, Noise-Canceling and Distortion-Canceling

NARCIS (Netherlands)

Blaakmeer, S.C.; Klumperink, Eric A.M.; Leenaerts, D.M.W.; Nauta, Bram

2008-01-01

An inductorless low-noise amplifier (LNA) with active balun is proposed for multi-standard radio applications between 100 MHz and 6 GHz. It exploits a combination of a common-gate (CGH) stage and an admittance-scaled common-source (CS) stage with replica biasing to maximize balanced operation, while

Partial Cancellation

Indian Academy of Sciences (India)

First page Back Continue Last page Overview Graphics. Partial Cancellation. Full Cancellation is desirable. But complexity requirements are enormous. 4000 tones, 100 Users billions of flops !!! Main Idea: Challenge: To determine which cross-talker to cancel on what “tone” for a given victim. Constraint: Total complexity is ...

Intelligent coil drum with electromagnetic force cancellation for MRI equipment

International Nuclear Information System (INIS)

Qiu, Jinhao; Tani, Junji; Ohtomo, Kikuo

1995-01-01

High-level noise induced in MRI equipment has been a main obstacle for their wide application in medical diagnosis. The noise is caused by the vibration of the cylindrical shell used to support the gradient magnetic field coils in MRI. In this study, a reduced-size model of the coil drum is constructed using polymer films and piezoelectric films. The piezoelectric films are divided into several patches and two patches of them are used as integrated bending actuators in the control of the shell vibration so that no external actuators are needed. The disturbance cancellation method is used since the shell is excited by predetermined forces. The relationships between the size, position and output magnitude of the actuators and control effect are also discussed. Experiment and simulation were carried out for the cases where the shell was excited at resonance frequencies of three main modes. The results show that the disturbance cancellation method in combination with the piezoelectric film actuators can successfully suppress the forced vibration of the shell and that the minimum amplitude of controlled vibration varies with the resonance mode. (author)

36 CFR 51.11 - May the Director amend, extend, or cancel a prospectus or solicitation?

Science.gov (United States)

2010-07-01

..., extend, or cancel a prospectus or solicitation? 51.11 Section 51.11 Parks, Forests, and Public Property... Procedures § 51.11 May the Director amend, extend, or cancel a prospectus or solicitation? The Director may... cancel a solicitation at any time prior to award of the concession contract if the Director determines in...

A New Probe Noise Approach For Acoustic Feedback Cancellation In Hearing Aids

DEFF Research Database (Denmark)

Guo, Meng; Jensen, Søren Holdt; Jensen, Jesper

Acoustic feedback is a big challenge in hearing aids. If not appropriately treated, the feedback limits the maximum possible amplification and may lead to significant sound distortions. In a state-of-the-art hearing aid, an acoustic feedback cancellation (AFC) system is used to compensate...

Hardware design and implementation of a wavelet de-noising procedure for medical signal preprocessing.

Science.gov (United States)

Chen, Szi-Wen; Chen, Yuan-Ho

2015-10-16

In this paper, a discrete wavelet transform (DWT) based de-noising with its applications into the noise reduction for medical signal preprocessing is introduced. This work focuses on the hardware realization of a real-time wavelet de-noising procedure. The proposed de-noising circuit mainly consists of three modules: a DWT, a thresholding, and an inverse DWT (IDWT) modular circuits. We also proposed a novel adaptive thresholding scheme and incorporated it into our wavelet de-noising procedure. Performance was then evaluated on both the architectural designs of the software and. In addition, the de-noising circuit was also implemented by downloading the Verilog codes to a field programmable gate array (FPGA) based platform so that its ability in noise reduction may be further validated in actual practice. Simulation experiment results produced by applying a set of simulated noise-contaminated electrocardiogram (ECG) signals into the de-noising circuit showed that the circuit could not only desirably meet the requirement of real-time processing, but also achieve satisfactory performance for noise reduction, while the sharp features of the ECG signals can be well preserved. The proposed de-noising circuit was further synthesized using the Synopsys Design Compiler with an Artisan Taiwan Semiconductor Manufacturing Company (TSMC, Hsinchu, Taiwan) 40 nm standard cell library. The integrated circuit (IC) synthesis simulation results showed that the proposed design can achieve a clock frequency of 200 MHz and the power consumption was only 17.4 mW, when operated at 200 MHz.

Quiet comfort: noise, otherness, and the mobile production of personal space.

Science.gov (United States)

Hagood, Mack

2011-01-01

Marketing, news reports, and reviews of Bose QuietComfort noise-canceling headphones position them as essential gear for the mobile rational actor of the neoliberal market—the business traveler. This article concerns noise-canceling headphones’ utility as soundscaping devices, which render a sense of personal space by mediating sound. The airplane and airport are paradoxical spaces in which the pursuit of freedom impedes its own enjoyment. Rather than fight the discomforts of air travel as a systemic problem, travelers use the tactic of soundscaping to suppress the perceived presence of others. Attention to soundscaping enables the scholar to explore relationships between media, space, freedom, otherness, and selfhood in an era characterized by neoliberalism and increased mobility. Air travel is a moment in which people with diverse backgrounds, beliefs, and bodies crowd together in unusually close proximity. Noise is the sound of individualism and difference in conflict. Noise is othered sound, and like any type of othering, the perception of noise is socially constructed and situated in hierarchies of race, class, age, and gender. The normative QuietComfort user in media representations is white, male, rational, monied, and mobile; women, children, and “chatty” passengers are cast as noisemakers. Moreover, in putting on noise-canceling headphones, diverse selves put on the historically Western subjectivity that has been built into their technology, one that suppresses the noise of difference in favor of the smooth circulation of people, information, and commodities.

Electrocardiogram de-noising based on forward wavelet transform ...

Indian Academy of Sciences (India)

Ratio (SNR) and Mean Square Error (MSE) computations showed that our proposed ... This technique permits to cancel noises and retain the informa- tion of the ... Wavelet analysis is used for transforming the signal under investigation into joined temporal and ... introduced the BWT in our proposed ECG de-noising system.

Hardware Design and Implementation of a Wavelet De-Noising Procedure for Medical Signal Preprocessing

Directory of Open Access Journals (Sweden)

Szi-Wen Chen

2015-10-01

Full Text Available In this paper, a discrete wavelet transform (DWT based de-noising with its applications into the noise reduction for medical signal preprocessing is introduced. This work focuses on the hardware realization of a real-time wavelet de-noising procedure. The proposed de-noising circuit mainly consists of three modules: a DWT, a thresholding, and an inverse DWT (IDWT modular circuits. We also proposed a novel adaptive thresholding scheme and incorporated it into our wavelet de-noising procedure. Performance was then evaluated on both the architectural designs of the software and. In addition, the de-noising circuit was also implemented by downloading the Verilog codes to a field programmable gate array (FPGA based platform so that its ability in noise reduction may be further validated in actual practice. Simulation experiment results produced by applying a set of simulated noise-contaminated electrocardiogram (ECG signals into the de-noising circuit showed that the circuit could not only desirably meet the requirement of real-time processing, but also achieve satisfactory performance for noise reduction, while the sharp features of the ECG signals can be well preserved. The proposed de-noising circuit was further synthesized using the Synopsys Design Compiler with an Artisan Taiwan Semiconductor Manufacturing Company (TSMC, Hsinchu, Taiwan 40 nm standard cell library. The integrated circuit (IC synthesis simulation results showed that the proposed design can achieve a clock frequency of 200 MHz and the power consumption was only 17.4 mW, when operated at 200 MHz.

Analysis, Design, and Evaluation of Acoustic Feedback Cancellation Systems for Hearing Aids

DEFF Research Database (Denmark)

Guo, Meng

2013-01-01

Acoustic feedback problems occur when the output loudspeaker signal of an audio system is partly returned to the input microphone via an acoustic coupling through the air. This problem often causes significant performance degradations in applications such as public address systems and hearing aids....... In the worst case, the audio system becomes unstable and howling occurs. In this work, first we analyze a general multiple microphone audio processing system, where a cancellation system using adaptive filters is used to cancel the effect of acoustic feedback. We introduce and derive an accurate approximation...... in acoustic feedback cancellation for hearing aids. It utilizes a probe noise signal which is generated with a specific characteristic so that it can facilitate an unbiased adaptive filter estimation with fast tracking of feedback path variations/changes despite its low signal level. We show in a hearing aid...

An Integrated Real-Time Beamforming and Postfiltering System for Nonstationary Noise Environments

Directory of Open Access Journals (Sweden)

Gannot Sharon

2003-01-01

Full Text Available We present a novel approach for real-time multichannel speech enhancement in environments of nonstationary noise and time-varying acoustical transfer functions (ATFs. The proposed system integrates adaptive beamforming, ATF identification, soft signal detection, and multichannel postfiltering. The noise canceller branch of the beamformer and the ATF identification are adaptively updated online, based on hypothesis test results. The noise canceller is updated only during stationary noise frames, and the ATF identification is carried out only when desired source components have been detected. The hypothesis testing is based on the nonstationarity of the signals and the transient power ratio between the beamformer primary output and its reference noise signals. Following the beamforming and the hypothesis testing, estimates for the signal presence probability and for the noise power spectral density are derived. Subsequently, an optimal spectral gain function that minimizes the mean square error of the log-spectral amplitude (LSA is applied. Experimental results demonstrate the usefulness of the proposed system in nonstationary noise environments.

Integration of Bass Enhancement and Active Noise Control System in Automobile Cabin

Directory of Open Access Journals (Sweden)

Liang Wang

2008-01-01

Full Text Available With the advancement of digital signal processing technologies, consumers are more concerned with the quality of multimedia entertainment in automobiles. In order to meet this demand, an audio enhancement system is needed to improve bass reproduction and cancel engine noise in the cabins. This paper presents an integrated active noise control system that is based on frequency-sampling filters to track and extract the bass information from the audio signal, and a multifrequency active noise equalizer to tune the low-frequency engine harmonics to enhance the bass reproduction. In the noise cancellation mode, a maximum of 3 dB bass enhancement can be achieved with significant noise suppression, while higher bass enhancement can be achieved in the bass enhance mode. The results show that the proposed system is effective for solving both the bass audio reproduction and the noise control problems in automobile cabins.

Improved Noise Minimum Statistics Estimation Algorithm for Using in a Speech-Passing Noise-Rejecting Headset

Directory of Open Access Journals (Sweden)

Seyedtabaee Saeed

2010-01-01

Full Text Available This paper deals with configuration of an algorithm to be used in a speech-passing angle grinder noise-canceling headset. Angle grinder noise is annoying and interrupts ordinary oral communication. Meaning that, low SNR noisy condition is ahead. Since variation in angle grinder working condition changes noise statistics, the noise will be nonstationary with possible jumps in its power. Studies are conducted for picking an appropriate algorithm. A modified version of the well-known spectral subtraction shows superior performance against alternate methods. Noise estimation is calculated through a multi-band fast adapting scheme. The algorithm is adapted very quickly to the non-stationary noise environment while inflecting minimum musical noise and speech distortion on the processed signal. Objective and subjective measures illustrating the performance of the proposed method are introduced.

Noise Reduction Efforts for Special Operations C-130 Aircraft Using Active Synchrophaser Control

National Research Council Canada - National Science Library

Hammond, Daryl; McKinley, Richard; Hale, Bill

1998-01-01

.... A more complicated approach uses an active noise cancellation (ANC) system, which offers improved performance that can augment passive methods to significantly reduce both internal and external aircraft noise...

A procedure for the assessment of low frequency noise complaints.

Science.gov (United States)

Moorhouse, Andy T; Waddington, David C; Adams, Mags D

2009-09-01

The development and application of a procedure for the assessment of low frequency noise (LFN) complaints are described. The development of the assessment method included laboratory tests addressing low frequency hearing threshold and the effect on acceptability of fluctuation, and field measurements complemented with interview-based questionnaires. Environmental health departments then conducted a series of six trials with genuine "live" LFN complaints to test the workability and usefulness of the procedure. The procedure includes guidance notes and a pro-forma report with step-by-step instructions. It does not provide a prescriptive indicator of nuisance but rather gives a systematic procedure to help environmental health practitioners to form their own opinion. Examples of field measurements and application of the procedure are presented. The procedure and examples are likely to be of particular interest to environmental health practitioners involved in the assessment of LFN complaints.

Adaptive Nonlinear RF Cancellation for Improved Isolation in Simultaneous Transmit–Receive Systems

Science.gov (United States)

Kiayani, Adnan; Waheed, Muhammad Zeeshan; Anttila, Lauri; Abdelaziz, Mahmoud; Korpi, Dani; Syrjala, Ville; Kosunen, Marko; Stadius, Kari; Ryynanen, Jussi; Valkama, Mikko

2018-05-01

This paper proposes an active radio frequency (RF) cancellation solution to suppress the transmitter (TX) passband leakage signal in radio transceivers supporting simultaneous transmission and reception. The proposed technique is based on creating an opposite-phase baseband equivalent replica of the TX leakage signal in the transceiver digital front-end through adaptive nonlinear filtering of the known transmit data, to facilitate highly accurate cancellation under a nonlinear TX power amplifier (PA). The active RF cancellation is then accomplished by employing an auxiliary transmitter chain, to generate the actual RF cancellation signal, and combining it with the received signal at the receiver (RX) low noise amplifier (LNA) input. A closed-loop parameter learning approach, based on the decorrelation principle, is also developed to efficiently estimate the coefficients of the nonlinear cancellation filter in the presence of a nonlinear TX PA with memory, finite passive isolation, and a nonlinear RX LNA. The performance of the proposed cancellation technique is evaluated through comprehensive RF measurements adopting commercial LTE-Advanced transceiver hardware components. The results show that the proposed technique can provide an additional suppression of up to 54 dB for the TX passband leakage signal at the RX LNA input, even at considerably high transmit power levels and with wide transmission bandwidths. Such novel cancellation solution can therefore substantially improve the TX-RX isolation, hence reducing the requirements on passive isolation and RF component linearity, as well as increasing the efficiency and flexibility of the RF spectrum use in the emerging 5G radio networks.

Performance analysis of power-efficient adaptive interference cancelation in fading channels

KAUST Repository

Radaydeh, Redha Mahmoud Mesleh; Alouini, Mohamed-Slim

2010-01-01

This paper analyzes the performance of a -steering scheme for highly correlated receive antennas in the presence of statistically unordered co-channel interferers over multipath fading channels. An adaptive activation of receive antennas according to the interfering signals fading conditions is considered in the analysis. Analytical expressions for various system performance measures, including the outage probability, average error probability of different signaling schemes, and raw moments of the combined signal-to-interference-plus-noise ratio (SINR) are obtained in exact forms. Numerical and simulation results for the performance-complexity tradeoff of this scheme is presented and then compared with that of full-size arbitrary interference cancelation and no cancelation scenarios. ©2010 IEEE.

Performance analysis of power-efficient adaptive interference cancelation in fading channels

KAUST Repository

Radaydeh, Redha Mahmoud Mesleh

2010-12-01

This paper analyzes the performance of a -steering scheme for highly correlated receive antennas in the presence of statistically unordered co-channel interferers over multipath fading channels. An adaptive activation of receive antennas according to the interfering signals fading conditions is considered in the analysis. Analytical expressions for various system performance measures, including the outage probability, average error probability of different signaling schemes, and raw moments of the combined signal-to-interference-plus-noise ratio (SINR) are obtained in exact forms. Numerical and simulation results for the performance-complexity tradeoff of this scheme is presented and then compared with that of full-size arbitrary interference cancelation and no cancelation scenarios. ©2010 IEEE.

A single antenna interference cancellation and adaptive technique based on ALOE

Directory of Open Access Journals (Sweden)

Xu Han

2017-02-01

Full Text Available A new type of single antenna interference cancellation (SAIC algorithm based on ALOE filtering module is introduced for co-channel interference cancellation in GSM/GPRS/EDGE downlink without changing the link structure of traditional receiver.Meanwhile,an adjacent frequency adaptive detection based on power spectrum estimation method is introduced to solve adjacent frequency interference and complex interference.Compared with traditional energy noise estimation method,the new method has simpler structure,less complexity,and can effectively improve the adaptability for various scenarios.The simulation results show that it can raise the resistance to co-channel frequency interference and adjacent frequency interference in multimode chips with low complexity,which improves the quality of 2G voice communication.

Evaluation of a Noise Reduction Procedure for Chest Radiography

Science.gov (United States)

Fukui, Ryohei; Ishii, Rie; Kodani, Kazuhiko; Kanasaki, Yoshiko; Suyama, Hisashi; Watanabe, Masanari; Nakamoto, Masaki; Fukuoka, Yasushi

2013-01-01

Background The aim of this study was to evaluate the usefulness of noise reduction procedure (NRP), a function in the new image processing for chest radiography. Methods A CXDI-50G Portable Digital Radiography System (Canon) was used for X-ray detection. Image noise was analyzed with a noise power spectrum (NPS) and a burger phantom was used for evaluation of density resolution. The usefulness of NRP was evaluated by chest phantom images and clinical chest radiography. We employed the Bureau of Radiological Health Method for scoring chest images while carrying out our observations. Results NPS through the use of NRP was improved compared with conventional image processing (CIP). The results in image quality showed high-density resolution through the use of NRP, so that chest radiography examination can be performed with a low dose of radiation. Scores were significantly higher than for CIP. Conclusion In this study, use of NRP led to a high evaluation in these so we are able to confirm the usefulness of NRP for clinical chest radiography. PMID:24574577

Signal processing method for Johnson noise thermometry

International Nuclear Information System (INIS)

Hwang, I. G.; Moon, B. S.; Kinser, Rpger

2003-01-01

The development of Johnson Noise Thermometry requires a high sensitive preamplifier circuit to pick up the temperature-related noise on the sensing element. However, the random noise generated in this amplification circuit causes a significant erroneous influence to the measurement. This paper describes signal processing mechanism of the Johnson Noise Thermometry system which is underway of development in collaboration between KAERI and ORNL. It adopts two identical amplifier channels and utilizes a digital signal processing technique to remove the independent noise of each channel. The CPSD(Cross Power Spectral Density) function is used to cancel the independent noise and the differentiation of narrow or single frequency peak from the CPSD data separates the common mode electromagnetic interference noise

Doubling the spectrum of time-domain induced polarization: removal of non-linear self-potential drift, harmonic noise and spikes, tapered gating, and uncertainty estimation

DEFF Research Database (Denmark)

Olsson, Per-Ivar; Fiandaca, Gianluca; Larsen, Jakob Juul

, a logarithmic gate width distribution for optimizing IP data quality and an estimate of gating uncertainty. Additional steps include modelling and cancelling of non-linear background drift and harmonic noise and a technique for efficiently identifying and removing spikes. The cancelling of non-linear background...... drift is based on a Cole-Cole model which effectively handles current induced electrode polarization drift. The model-based cancelling of harmonic noise reconstructs the harmonic noise as a sum of harmonic signals with a common fundamental frequency. After segmentation of the signal and determining....... The processing steps is successfully applied on full field profile data sets. With the model-based cancelling of harmonic noise, the first usable IP gate is moved one decade closer to time zero. Furthermore, with a Cole-Cole background drift model the shape of the response at late times is accurately retrieved...

Reactor noise monitoring device

International Nuclear Information System (INIS)

Yamanaka, Hiroto.

1990-01-01

The present invention concerns a reactor noise monitoring device by detecting abnormal sounds in background noises. Vibration sounds detected by accelerometers are applied to a loose parts detector. The detector generates high alarm if there are sudden impact sounds in the background noises and applies output signals to an accumulation device. If there is slight impact sounds in the vicinity of any of the accelerometers, the accumulation device accumulates the abnormal sounds assumed to be generated from an identical site while synchronizing the waveforms for all of the channels. Then, the device outputs signals in which the background noises are cancelled, as detection signals. Therefore, S/N ratio can be improved and the abnormal sounds contained in the background noises can be detected, to thereby improve the accuracy for estimating the position where the abnormal sounds are generated. (I.S.)

The experimental plan of displacement- and frequency-noise free laser interferometer

International Nuclear Information System (INIS)

Kokeyama, K; Sato, S; Kawamura, S; Nishizawa, A; Chen, Y; Pai, A; Somiya, K; Ward, R; Sugamoto, A

2008-01-01

We present the partial demonstration of displacement- and laser-noise free interferometer (DFI) and the next experimental plan to examine the complete configuration. A part of the full implementation of DFI has been demonstrated to confirm the cancellation of beamsplitter displacements. The displacements were suppressed by about two orders of magnitude. The aim of the next experiment is to operate the system and to confirm the cancellation of all displacement noises, while the gravitational wave (GW) signals survive. The optical displacements will be simulated by electro-optic modulators (EOM). To simulate the GW contribution to laser lights, we will use multiple EOMs

Robustness against parametric noise of nonideal holonomic gates

International Nuclear Information System (INIS)

Lupo, Cosmo; Aniello, Paolo; Napolitano, Mario; Florio, Giuseppe

2007-01-01

Holonomic gates for quantum computation are commonly considered to be robust against certain kinds of parametric noise, the cause of this robustness being the geometric character of the transformation achieved in the adiabatic limit. On the other hand, the effects of decoherence are expected to become more and more relevant when the adiabatic limit is approached. Starting from the system described by Florio et al. [Phys. Rev. A 73, 022327 (2006)], here we discuss the behavior of nonideal holonomic gates at finite operational time, i.e., long before the adiabatic limit is reached. We have considered several models of parametric noise and studied the robustness of finite-time gates. The results obtained suggest that the finite-time gates present some effects of cancellation of the perturbations introduced by the noise which mimic the geometrical cancellation effect of standard holonomic gates. Nevertheless, a careful analysis of the results leads to the conclusion that these effects are related to a dynamical instead of a geometrical feature

Robustness against parametric noise of nonideal holonomic gates

Science.gov (United States)

Lupo, Cosmo; Aniello, Paolo; Napolitano, Mario; Florio, Giuseppe

2007-07-01

Holonomic gates for quantum computation are commonly considered to be robust against certain kinds of parametric noise, the cause of this robustness being the geometric character of the transformation achieved in the adiabatic limit. On the other hand, the effects of decoherence are expected to become more and more relevant when the adiabatic limit is approached. Starting from the system described by Florio [Phys. Rev. A 73, 022327 (2006)], here we discuss the behavior of nonideal holonomic gates at finite operational time, i.e., long before the adiabatic limit is reached. We have considered several models of parametric noise and studied the robustness of finite-time gates. The results obtained suggest that the finite-time gates present some effects of cancellation of the perturbations introduced by the noise which mimic the geometrical cancellation effect of standard holonomic gates. Nevertheless, a careful analysis of the results leads to the conclusion that these effects are related to a dynamical instead of a geometrical feature.

Improved Iterative Parallel Interference Cancellation Receiver for Future Wireless DS-CDMA Systems

Directory of Open Access Journals (Sweden)

Andrea Bernacchioni

2005-04-01

Full Text Available We present a new turbo multiuser detector for turbo-coded direct sequence code division multiple access (DS-CDMA systems. The proposed detector is based on the utilization of a parallel interference cancellation (PIC and a bank of turbo decoders. The PIC is broken up in order to perform interference cancellation after each constituent decoder of the turbo decoding scheme. Moreover, in the paper we propose a new enhanced algorithm that provides a more accurate estimation of the signal-to-noise-plus-interference-ratio used in the tentative decision device and in the MAP decoding algorithm. The performance of the proposed receiver is evaluated by means of computer simulations for medium to very high system loads, in AWGN and multipath fading channel, and compared to recently proposed interference cancellation-based iterative MUD, by taking into account the number of iterations and the complexity involved. We will see that the proposed receiver outperforms the others especially for highly loaded systems.

Combined Effect of Random Transmit Power Control and Inter-Path Interference Cancellation on DS-CDMA Packet Mobile Communications

Science.gov (United States)

Kudoh, Eisuke; Ito, Haruki; Wang, Zhisen; Adachi, Fumiyuki

In mobile communication systems, high speed packet data services are demanded. In the high speed data transmission, throughput degrades severely due to severe inter-path interference (IPI). Recently, we proposed a random transmit power control (TPC) to increase the uplink throughput of DS-CDMA packet mobile communications. In this paper, we apply IPI cancellation in addition to the random TPC. We derive the numerical expression of the received signal-to-interference plus noise power ratio (SINR) and introduce IPI cancellation factor. We also derive the numerical expression of system throughput when IPI is cancelled ideally to compare with the Monte Carlo numerically evaluated system throughput. Then we evaluate, by Monte-Carlo numerical computation method, the combined effect of random TPC and IPI cancellation on the uplink throughput of DS-CDMA packet mobile communications.

Infra-sound cancellation and mitigation in wind turbines

Science.gov (United States)

Boretti, Albert; Ordys, Andrew; Al Zubaidy, Sarim

2018-03-01

The infra-sound spectra recorded inside homes located even several kilometres far from wind turbine installations is characterized by large pressure fluctuation in the low frequency range. There is a significant body of literature suggesting inaudible sounds at low frequency are sensed by humans and affect the wellbeing through different mechanisms. These mechanisms include amplitude modulation of heard sounds, stimulating subconscious pathways, causing endolymphatic hydrops, and possibly potentiating noise-induced hearing loss. We suggest the study of infra-sound active cancellation and mitigation to address the low frequency noise issues. Loudspeakers generate pressure wave components of same amplitude and frequency but opposite phase of the recorded infra sound. They also produce pressure wave components within the audible range reducing the perception of the infra-sound to minimize the sensing of the residual infra sound.

Factors impacting same-day cancellation of outpatient pediatric magnetic resonance imaging under anesthesia

International Nuclear Information System (INIS)

Hoffman, Andrea S.; Matlow, Anne; Shroff, Manohar; Cohen, Eyal

2015-01-01

Studies of elective surgical procedures indicate that cancellation is common and preventable. Little is known about cancellation of anesthesia-supported elective diagnostic imaging. To describe the reasons for same-day cancellation of MRI studies performed under sedation or anesthesia and identify patient characteristics associated with cancellations. This case-control study was carried out in a university-affiliated tertiary care children's hospital. Cases were defined as elective outpatient MRI studies booked under anesthesia that were cancelled after the patient had arrived in the radiology department in 2009. Matched controls were identified by selecting the same day and time 1 week before or after the cancelled case. Main outcome measures included demographics, MRI study characteristics, and social and medical factors. There were 111 outpatient anesthesia-supported MRI studies cancelled on the same day as the assessment (cancellation rate: 4.5%), of which 74.6% were related to family and patient factors, while 22% were related to system factors. Cancelled cases involved patients who lived in lower median income quintile neighborhoods compared to controls (2 vs. 3; P = 0.0007; odds ratio [OR] 3.81; 95% confidence interval [CI] 1.18-12.34). Those who traveled a greater median distance (in kilometers) were less likely to be cancelled (18.8 vs. 27.1, P = 0.0035). Although cancelled patients had a lower mean number of total medical services (2.5 vs. 3.0; P = 0.03; OR = 0.78; 95% CI 0.62-0.98), current medical factors (past 12 months) did not impact cancellations. Same-day cancellations of anesthesia-supported MRI studies are not uncommon, and the main predictor of cancellation seems to be socioeconomic rather than medical. (orig.)

Factors impacting same-day cancellation of outpatient pediatric magnetic resonance imaging under anesthesia

Energy Technology Data Exchange (ETDEWEB)

Hoffman, Andrea S. [University of Toronto, Department of Paediatrics, Division of Developmental Paediatrics, Holland Bloorview Kids Rehabilitation Hospital, Toronto (Canada); Matlow, Anne [University of Toronto, Strategic Initiatives, Postgraduate Medical Education, Toronto (Canada); Shroff, Manohar [University of Toronto, Department of Diagnostic Imaging, Division of Neuroradiology, Hospital for Sick Children, Toronto (Canada); Cohen, Eyal [University of Toronto, Division of Paediatric Medicine and Child Health Evaluative Sciences, Hospital for Sick Children, Department of Paediatrics and Institute of Health Policy, Management and Evaluation, Toronto (Canada)

2014-07-24

Studies of elective surgical procedures indicate that cancellation is common and preventable. Little is known about cancellation of anesthesia-supported elective diagnostic imaging. To describe the reasons for same-day cancellation of MRI studies performed under sedation or anesthesia and identify patient characteristics associated with cancellations. This case-control study was carried out in a university-affiliated tertiary care children's hospital. Cases were defined as elective outpatient MRI studies booked under anesthesia that were cancelled after the patient had arrived in the radiology department in 2009. Matched controls were identified by selecting the same day and time 1 week before or after the cancelled case. Main outcome measures included demographics, MRI study characteristics, and social and medical factors. There were 111 outpatient anesthesia-supported MRI studies cancelled on the same day as the assessment (cancellation rate: 4.5%), of which 74.6% were related to family and patient factors, while 22% were related to system factors. Cancelled cases involved patients who lived in lower median income quintile neighborhoods compared to controls (2 vs. 3; P = 0.0007; odds ratio [OR] 3.81; 95% confidence interval [CI] 1.18-12.34). Those who traveled a greater median distance (in kilometers) were less likely to be cancelled (18.8 vs. 27.1, P = 0.0035). Although cancelled patients had a lower mean number of total medical services (2.5 vs. 3.0; P = 0.03; OR = 0.78; 95% CI 0.62-0.98), current medical factors (past 12 months) did not impact cancellations. Same-day cancellations of anesthesia-supported MRI studies are not uncommon, and the main predictor of cancellation seems to be socioeconomic rather than medical. (orig.)

An Analysis Of Pole/zero Cancellation In LTR-based Feedback Design

DEFF Research Database (Denmark)

Niemann, Hans Henrik; Jannerup, Ole Erik

1990-01-01

The pole/zero cancellation in LTR-based feedback design will be analyzed for both full-order as well as minimal-order observers. The asymptotic behaviour of the sensitivity function from the LTR-procedure are given in explicit expressions in the case when a zero is not cancelled by an equivalent...... pole. It will be shown that the non-minimum phase case is included as a special case. The results are not based on any specific LTR-method....

A Review on Successive Interference Cancellation Scheme Based on Optical CDMA Network

Science.gov (United States)

Alsowaidi, N.; Eltaif, T.; Mokhtar, M. R.

2014-12-01

Due to various desirable features of optical code division multiple access (OCDMA), it is believed this technique once developed and commercially available will be an integral part of optical access networks. Optical CDMA system suffers from a problem called multiple access interference (MAI) which limits the number of active users, it occurs when number of active users share the same carriers. The aim of this paper is to review successive interference cancellation (SIC) scheme based on optical CDMA system. The paper also reviews the system performance in presence of shot noise, thermal noise, and phase-induced intensity noise (PIIN). A comprehensive review on the mathematical model of SIC scheme using direct detection (DS) and spectral amplitude coding (SAC) were presented in this article.

1-Gb/s zero-pole cancellation CMOS transimpedance amplifier for Gigabit Ethernet applications

International Nuclear Information System (INIS)

Huang Beiju; Zhang Xu; Chen Hongda

2009-01-01

A zero-pole cancellation transimpedance amplifier (TIA) has been realized in 0.35 μm RF CMOS technology for Gigabit Ethernet applications. The TIA exploits a zero-pole cancellation configuration to isolate the input parasitic capacitance including photodiode capacitance from bandwidth deterioration. Simulation results show that the proposed TIA has a bandwidth of 1.9 GHz and a transimpedance gain of 65 dB·Ω for 1.5 pF photodiode capacitance, with a gain-bandwidth product of 3.4 THz·Ω. Even with 2 pF photodiode capacitance, the bandwidth exhibits a decline of only 300 MHz, confirming the mechanism of the zero-pole cancellation configuration. The input resistance is 50 Ω, and the average input noise current spectral density is 9.7 pA/√Hz. Testing results shows that the eye diagram at 1 Gb/s is wide open. The chip dissipates 17 mW under a single 3.3 V supply.

1-Gb/s zero-pole cancellation CMOS transimpedance amplifier for Gigabit Ethernet applications

Energy Technology Data Exchange (ETDEWEB)

Huang Beiju; Zhang Xu; Chen Hongda, E-mail: bjhuang@semi.ac.c [State Key Laboratory of Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

2009-10-15

A zero-pole cancellation transimpedance amplifier (TIA) has been realized in 0.35 {mu}m RF CMOS technology for Gigabit Ethernet applications. The TIA exploits a zero-pole cancellation configuration to isolate the input parasitic capacitance including photodiode capacitance from bandwidth deterioration. Simulation results show that the proposed TIA has a bandwidth of 1.9 GHz and a transimpedance gain of 65 dB{center_dot}{Omega} for 1.5 pF photodiode capacitance, with a gain-bandwidth product of 3.4 THz{center_dot}{Omega}. Even with 2 pF photodiode capacitance, the bandwidth exhibits a decline of only 300 MHz, confirming the mechanism of the zero-pole cancellation configuration. The input resistance is 50 {Omega}, and the average input noise current spectral density is 9.7 pA/{radical}Hz. Testing results shows that the eye diagram at 1 Gb/s is wide open. The chip dissipates 17 mW under a single 3.3 V supply.

Iterative Soft Decision Interference Cancellation for DS-CDMA Employing the Distribution of Interference

Directory of Open Access Journals (Sweden)

Gerstacker WolfgangH

2010-01-01

Full Text Available A well-known receiver strategy for direct-sequence code-division multiple-access (DS-CDMA transmission is iterative soft decision interference cancellation. For calculation of soft estimates used for cancellation, the distribution of residual interference is commonly assumed to be Gaussian. In this paper, we analyze matched filter-based iterative soft decision interference cancellation (MF ISDIC when utilizing an approximation of the actual probability density function (pdf of residual interference. In addition, a hybrid scheme is proposed, which reduces computational complexity by considering the strongest residual interferers according to their pdf while the Gaussian assumption is applied to the weak residual interferers. It turns out that the bit error ratio decreases already noticeably when only a small number of residual interferers is regarded according to their pdf. For the considered DS-CDMA transmission the bit error ratio decreases by 80% for high signal-to-noise ratios when modeling all residual interferers but the strongest three to be Gaussian distributed.

Mitigation of MIMO Co-Channel Interference using robust interference cancellation receiver

DEFF Research Database (Denmark)

Rahman, Muhammad Imadur; De Carvalho, Elisabeth; Prasad, Ramjee

2007-01-01

(STBC) link may become equivalent to an interfering Spatial Multiplexing (SM) link. Using this knowledge and understanding, we propose an interference cancellation receiver robust to different types of MIMO interferers at cell edge for the Downlink (DL) of cellular systems. The receiver systematically...... performs a multiple symbol processing: this is the appropriate processing when the signal of interest or the signal of interferer is correlated across symbols, which is the case for STBC transmission. We evaluated different link combinations in terms of Signal to Interference and Noise Ratio (SINR......) statistics and Bit Error Rate (BER) performance in cellular Orthogonal Frequency Division Multiple Access (OFDMA) systems. We have found that the proposed multiple-symbol linear interference cancellation receiver performs satisfactorily when any kind of single 'logical' stream MIMO scheme is present...

49 CFR 40.275 - What is the effect of procedural problems that are not sufficient to cancel an alcohol test?

Science.gov (United States)

2010-10-01

... not sufficient to cancel an alcohol test? 40.275 Section 40.275 Transportation Office of the Secretary... cancel an alcohol test? (a) As an STT, BAT, employer, or a service agent administering the testing... cancelled based on a mistake in the process that does not have a significant adverse effect on the right of...

Noise cancellation in magnetoencephalography and electroencephalography with isolated reference sensors

Science.gov (United States)

Kraus, Jr., Robert H.; Espy, Michelle A.; Matlachov, Andrei; Volegov, Petr

2010-06-01

An apparatus measures electromagnetic signals from a weak signal source. A plurality of primary sensors is placed in functional proximity to the weak signal source with an electromagnetic field isolation surface arranged adjacent the primary sensors and between the weak signal source and sources of ambient noise. A plurality of reference sensors is placed adjacent the electromagnetic field isolation surface and arranged between the electromagnetic isolation surface and sources of ambient noise.

Noise considerations for vital signs CW radar sensors

DEFF Research Database (Denmark)

Jensen, Brian Sveistrup; Jensen, Thomas; Zhurbenko, Vitaliy

2011-01-01

and the underlying signal theory for such sensors. Then to point out and especially clarify one of the most important effects aiding the design of vital signs radars (VSR), a more detailed discussion concerning phase noise cancellation (or filtering) by range correlation is given. This discussion leads to some...... general conclusions about which system components are the most critical concerning noise contribution and thus detection accuracy and dynamic range....

Adaptive EMG noise reduction in ECG signals using noise level approximation

Science.gov (United States)

Marouf, Mohamed; Saranovac, Lazar

2017-12-01

In this paper the usage of noise level approximation for adaptive Electromyogram (EMG) noise reduction in the Electrocardiogram (ECG) signals is introduced. To achieve the adequate adaptiveness, a translation-invariant noise level approximation is employed. The approximation is done in the form of a guiding signal extracted as an estimation of the signal quality vs. EMG noise. The noise reduction framework is based on a bank of low pass filters. So, the adaptive noise reduction is achieved by selecting the appropriate filter with respect to the guiding signal aiming to obtain the best trade-off between the signal distortion caused by filtering and the signal readability. For the evaluation purposes; both real EMG and artificial noises are used. The tested ECG signals are from the MIT-BIH Arrhythmia Database Directory, while both real and artificial records of EMG noise are added and used in the evaluation process. Firstly, comparison with state of the art methods is conducted to verify the performance of the proposed approach in terms of noise cancellation while preserving the QRS complex waves. Additionally, the signal to noise ratio improvement after the adaptive noise reduction is computed and presented for the proposed method. Finally, the impact of adaptive noise reduction method on QRS complexes detection was studied. The tested signals are delineated using a state of the art method, and the QRS detection improvement for different SNR is presented.

Possibilities of an efficient noise damping in the large gas-fueled boilers

International Nuclear Information System (INIS)

1994-01-01

This report describes a series of tests with the objective to develop a technique for active control, and suppression of unstable conditions of combustion in gas-fired boiler systems. The primary target group for this report are persons within the energy sector, including especially users of natural gas. Focus has been given more to the practical possibilities and limitations than to complicated acoustical theory. The technical background for this work is constituted by the latest innovations within active noise cancelling methods for low frequent noise in channel- and pipe shaped systems, such as heating-, air-and exhaust systems. The fundamental idea has been to implement already functioning and commercial available systems for active noise cancellation in an modified setup to a gasfired boiler system. A few examples of similar attempts are given. Latest a relatively successful example of actively controlling an unstable combustion in a channel shaped burner system (CNRS Paris 1993). The conclusion of the project is anyway, that unstable combustion in larger gasfired boilers can not be controlled by the active methods and systems known today. The reasons for this are: the flame and thus the noise source are distributed in space, the acoustical wave-propagation in the combustion chamber is complex and with low damping, several loops for unstable combustion are possible. Within this project special sensors for high temperatures are developed, e.g.: probe microphones, high temperature turbulence screens and a system for measuring of the variations in UV-light emission form the flame. These systems are applicable also for more 'traditional active noise cancellation' of low-frequent noise in exhaust pipes and chimneys. (au)

[Research on electrocardiogram de-noising algorithm based on wavelet neural networks].

Science.gov (United States)

Wan, Xiangkui; Zhang, Jun

2010-12-01

In this paper, the ECG de-noising technology based on wavelet neural networks (WNN) is used to deal with the noises in Electrocardiogram (ECG) signal. The structure of WNN, which has the outstanding nonlinear mapping capability, is designed as a nonlinear filter used for ECG to cancel the baseline wander, electromyo-graphical interference and powerline interference. The network training algorithm and de-noising experiments results are presented, and some key points of the WNN filter using ECG de-noising are discussed.

Scientific journal cancellations

CERN Multimedia

The Library

2001-01-01

Earlier this year the Scientific Information Policy Board (SIPB) requested the Library and the Working Group for Acquisitions to revise the current printed journal collection in order to cancel those titles that are less required. Savings could then be used for the development of other collections and particularly electronic resources needed to support CERN current research activities. A list of proposed cancellations was drawn and posted on the Library web pages: http://library.cern.ch/library_general/cancel.html The SIPB invites every one to check if any of the titles are of importance to their work, in which case you are invited to inform the Library before the 25th of September by sending an e-mail to: eliane.chaney@cern.ch Titles not reconsidered by the users will be cancelled by the end of the year. Thank you, The Library

Reasons for cancellation of operation on the day of intended surgery in a multidisciplinary 500 bedded hospital

Directory of Open Access Journals (Sweden)

Rajender Kumar

2012-01-01

Full Text Available Background: Cancellation of operations in hospitals is a significant problem with far reaching consequences. This study was planned to evaluate reasons for cancellation of elective surgical operation on the day of surgery in a 500 bedded Government hospital. Materials and Methods: The medical records of all the patients, from December 2009 to November 2010, who had their operations cancelled on the day of surgery in all surgical units of the hospital, were audited prospectively. The number of operation cancelled and reasons for cancellation were documented. Results: 7272 patients were scheduled for elective surgical procedures during study period; 1286 (17.6 % of these were cancelled on the day of surgery. The highest number of cancellation occurred in the discipline of general surgery (7.1% and the least (0.35% occurred in Ear-Nose-Throat surgery. The most common cause of cancellation was the lack of availability of theater time 809 (63% and patients not turning up 244 (19% patients. 149 cancellations (11.6% were because of medical reasons; 16 (1.2% were cancelled by the surgeon due to a change in the surgical plan; 28 (2.1% were cancelled as patients were not ready for surgery; and 40 (3.1% were cancelled due to equipment failure.]. Conclusion: Most causes of cancellations of operations are preventable.

Impulse Noise Cancellation of Medical Images Using Wavelet Networks and Median Filters

Science.gov (United States)

Sadri, Amir Reza; Zekri, Maryam; Sadri, Saeid; Gheissari, Niloofar

2012-01-01

This paper presents a new two-stage approach to impulse noise removal for medical images based on wavelet network (WN). The first step is noise detection, in which the so-called gray-level difference and average background difference are considered as the inputs of a WN. Wavelet Network is used as a preprocessing for the second stage. The second step is removing impulse noise with a median filter. The wavelet network presented here is a fixed one without learning. Experimental results show that our method acts on impulse noise effectively, and at the same time preserves chromaticity and image details very well. PMID:23493998

Design of low noise transimpedance amplifier for intravascular ultrasound

KAUST Repository

Reda, Dina

2009-11-01

In this paper, we study transimpedance amplifiers for capacitive sensing applications with a focus on Intravascular Ultra Sound (IVUS). We employ RF noise cancellation technique on capacitive feedback based transimpedance amplifiers. This technique eliminates the input-referred noise of TIAs completely and enhances the dynamic range of front-end electronics. Simulation results verify the proposed technique used in two different TIA topologies employing shunt-shunt feedback. ©2009 IEEE.

Adaptive cancellation of geomagnetic background noise for magnetic anomaly detection using coherence

International Nuclear Information System (INIS)

Liu, Dunge; Xu, Xin; Huang, Chao; Zhu, Wanhua; Liu, Xiaojun; Fang, Guangyou; Yu, Gang

2015-01-01

Magnetic anomaly detection (MAD) is an effective method for the detection of ferromagnetic targets against background magnetic fields. Currently, the performance of MAD systems is mainly limited by the background geomagnetic noise. Several techniques have been developed to detect target signatures, such as the synchronous reference subtraction (SRS) method. In this paper, we propose an adaptive coherent noise suppression (ACNS) method. The proposed method is capable of evaluating and detecting weak anomaly signals buried in background geomagnetic noise. Tests with real-world recorded magnetic signals show that the ACNS method can excellently remove the background geomagnetic noise by about 21 dB or more in high background geomagnetic field environments. Additionally, as a general form of the SRS method, the ACNS method offers appreciable advantages over the existing algorithms. Compared to the SRS method, the ACNS algorithm can eliminate the false target signals and represents a noise suppressing capability improvement of 6.4 dB. The positive outcomes in terms of intelligibility make this method a potential candidate for application in MAD systems. (paper)

Signal shaping and tail cancellation for gas proportional detectors at high counting rates

International Nuclear Information System (INIS)

Boie, R.A.; Hrisoho, A.T.; Rehak, P.

1982-01-01

A low noise, wide bandwidth preamplifier and signal processing filter were developed for high counting rate proportional counters. The filter consists of a seven pole Gaussian integrator with symmetrical weighting function and continuously variable shaping time, tausub(s), of 8-50 ns (fwhm) preceded by a second order pole/zero circuit which cancels the long (1/t) tails of the chamber signals. The preamplifier is an optimized common base input design with 2 ns rise time and an equivalent noise input charge < 2000 r.m.s. electrons, when connected to a chamber with 10 pF capacitance and at a filtering time, tausub(s), of 10 ns. (orig.)

30 CFR 250.181 - When may the Secretary cancel my lease and when am I compensated for cancellation?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When may the Secretary cancel my lease and when... may the Secretary cancel my lease and when am I compensated for cancellation? If the Secretary cancels.... Section 250.185 states conditions under which you will receive no compensation. The Secretary may cancel a...

Study of Cancelled Elective Surgical Operations

Directory of Open Access Journals (Sweden)

M Amrollahi

2004-07-01

Full Text Available Introduction: Cancellation of an elective operation is a very important problem, which is the cause for different types of stresses for patients and their families and results in loss of significant amount of time, money and hospital resources. Therefore, finding the main causes of operation postponement may help us to understand and reduce these problems. Material & Method: A special questionnaire was designed to gather information about different causes of operation cancellation and filled from October 23rd (Aban 1st till November 21st (Azar 30 th, 2001 (1380 in all of the teaching hospitals of Yazd university. (S.Dr Rahnemoon, Afshar, Rah Ahan, Bahman and Savaneg Sukhteghy Results were statistically evaluated.. Results: 180 of the 31437 scheduled operations had been cancelled (12.52% Majority of cases (33.3% had been cancelled due to the absence of the surgeons. This group ((Surgeons absent was the most common cause for the postponement of operations (36.7%. The secondary cause of cancellations was related to anesthetic team and operating room problems (25%, the patient’s reasons for cancellation was 16.2% and the most minimal cause of cancellation was insufficient hospital revenue (0.5%. The basis of disease or high risk patients for operation were the main causes of dysfunction of the anesthetic team (68.9% and also the first cause of cancellation. The rate of cancellation was the most in the "older than 60 years" age group. (15.4% The cancellation in women was 12.6% and in males 12.5%. Conclusion: Surgeons schedule more patients keeping in mind cancellations which occur regularly due to patients, hospital, anesthesia, and operating room problems. This over scheduling is a problem itself, so preadmission evaluation clinics are recommended to decrease the rate of cancellations thereby saving the socioeconomic resources and decreasing patient’s stress.

Tissue Cancellation in Dual Energy Mammography Using a Calibration Phantom Customized for Direct Mapping.

Science.gov (United States)

Han, Seokmin; Kang, Dong-Goo

2014-01-01

An easily implementable tissue cancellation method for dual energy mammography is proposed to reduce anatomical noise and enhance lesion visibility. For dual energy calibration, the images of an imaging object are directly mapped onto the images of a customized calibration phantom. Each pixel pair of the low and high energy images of the imaging object was compared to pixel pairs of the low and high energy images of the calibration phantom. The correspondence was measured by absolute difference between the pixel values of imaged object and those of the calibration phantom. Then the closest pixel pair of the calibration phantom images is marked and selected. After the calibration using direct mapping, the regions with lesion yielded different thickness from the background tissues. Taking advantage of the different thickness, the visibility of cancerous lesions was enhanced with increased contrast-to-noise ratio, depending on the size of lesion and breast thickness. However, some tissues near the edge of imaged object still remained after tissue cancellation. These remaining residuals seem to occur due to the heel effect, scattering, nonparallel X-ray beam geometry and Poisson distribution of photons. To improve its performance further, scattering and the heel effect should be compensated.

Introducing GAMER: A Fast and Accurate Method for Ray-tracing Galaxies Using Procedural Noise

Science.gov (United States)

Groeneboom, N. E.; Dahle, H.

2014-03-01

We developed a novel approach for fast and accurate ray-tracing of galaxies using procedural noise fields. Our method allows for efficient and realistic rendering of synthetic galaxy morphologies, where individual components such as the bulge, disk, stars, and dust can be synthesized in different wavelengths. These components follow empirically motivated overall intensity profiles but contain an additional procedural noise component that gives rise to complex natural patterns that mimic interstellar dust and star-forming regions. These patterns produce more realistic-looking galaxy images than using analytical expressions alone. The method is fully parallelized and creates accurate high- and low- resolution images that can be used, for example, in codes simulating strong and weak gravitational lensing. In addition to having a user-friendly graphical user interface, the C++ software package GAMER is easy to implement into an existing code.

Introducing GAMER: A fast and accurate method for ray-tracing galaxies using procedural noise

International Nuclear Information System (INIS)

Groeneboom, N. E.; Dahle, H.

2014-01-01

We developed a novel approach for fast and accurate ray-tracing of galaxies using procedural noise fields. Our method allows for efficient and realistic rendering of synthetic galaxy morphologies, where individual components such as the bulge, disk, stars, and dust can be synthesized in different wavelengths. These components follow empirically motivated overall intensity profiles but contain an additional procedural noise component that gives rise to complex natural patterns that mimic interstellar dust and star-forming regions. These patterns produce more realistic-looking galaxy images than using analytical expressions alone. The method is fully parallelized and creates accurate high- and low- resolution images that can be used, for example, in codes simulating strong and weak gravitational lensing. In addition to having a user-friendly graphical user interface, the C++ software package GAMER is easy to implement into an existing code.

Introducing GAMER: A fast and accurate method for ray-tracing galaxies using procedural noise

Energy Technology Data Exchange (ETDEWEB)

Groeneboom, N. E.; Dahle, H., E-mail: nicolaag@astro.uio.no [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, N-0315 Oslo (Norway)

2014-03-10

We developed a novel approach for fast and accurate ray-tracing of galaxies using procedural noise fields. Our method allows for efficient and realistic rendering of synthetic galaxy morphologies, where individual components such as the bulge, disk, stars, and dust can be synthesized in different wavelengths. These components follow empirically motivated overall intensity profiles but contain an additional procedural noise component that gives rise to complex natural patterns that mimic interstellar dust and star-forming regions. These patterns produce more realistic-looking galaxy images than using analytical expressions alone. The method is fully parallelized and creates accurate high- and low- resolution images that can be used, for example, in codes simulating strong and weak gravitational lensing. In addition to having a user-friendly graphical user interface, the C++ software package GAMER is easy to implement into an existing code.

Surgery cancellations at a public hospital

Directory of Open Access Journals (Sweden)

Erika Pittelkow

2008-12-01

Full Text Available Objective: To determine the frequency of cancellation of scheduledsurgeries at a public hospital in the city of São Paulo, and to identifythe reasons of cancellation. Methods: A descriptive, exploratory,retrospective study, with quantitative analysis, of records ofprocedures cancelled and medical charts of patients whose surgerieswere cancelled, between January 2006 and July 2007. Results: Ofthe 6,149 (100% surgeries scheduled for the period surveyed, 701(11.4% were canceled and 5,448 (88.6% conducted; among thesurgeries cancelled, most were general surgeries (237/33.8% andorthopedic surgery (200/28.5%; surgeons or assistant surgeons(518/73.9% and anesthesiologists (183/26.1% were responsible forcancellations. The primary reasons for cancellation were unfavorableclinical status of patients (225/32.1%, no show up of patients(119/17.0%, change in medical management (79/11.3%, patientnot appropriately prepared (53/7.5% and lack of material (52/7.4%.Conclusions: This study enabled identifying the frequency and causesof surgical cancellations at a public hospital, so as to contribute toimproving professional performance in this area.

Management implications for the perioperative surgical home related to inpatient case cancellations and add-on case scheduling on the day of surgery.

Science.gov (United States)

Epstein, Richard H; Dexter, Franklin

2015-07-01

The American Society of Anesthesiologists has embraced the concept of the Perioperative Surgical Home as a means through which anesthesiologists can add value to the health systems in which they practice. One key listed element of the Perioperative Surgical Home is to support "scheduling initiatives to reduce cancellations and increase efficiency." In this study, we explored the potential benefits of the Perioperative Surgical Home with respect to inpatient cancellations and add-on case scheduling. We evaluated 6 hypotheses related to the timing of inpatient cancellations and preoperative anesthesia evaluations. Inpatient cancellations were studied during 26 consecutive 4-week intervals between July 2012 and June 2014 at a tertiary care academic hospital. All timestamps related to scheduling, rescheduling, and cancellation activities were retrieved from the operating room (OR) case scheduling system. Timestamps when patients were seen by anesthesia residents were obtained from the preoperative evaluation system database. Batch mean methods were used to calculate means and SE. For cases cancelled, we determined whether, for "most" (>50%) cancellations, a subsequent procedure (of any type) was performed on the patient within 7 days of the cancellation. Comparisons with most and other fractions were assessed using the 1 group, 1-sided Student t test. We evaluated whether a few procedures were highly represented among the cancelled cases via the Herfindahl (Simpson's) index, comparing it with Data from 24,735 scheduled inpatient cases were assessed. Cases cancelled after 7 AM on the day before or at any time on the scheduled day of surgery accounted for 22.6% ± 0.5% (SE) of the scheduled minutes all scheduled cases, and 26.8% ± 0.4% of the case volume (i.e., number of cases). Most (83.1% ± 0.6%, P 50%, P = 0.12), implying that the indication for the cancelled procedure no longer existed or the patient/family decided not to proceed with surgery. When only

20 CFR 217.27 - Effect of cancellation.

Science.gov (United States)

2010-04-01

... ANNUITY OR LUMP SUM Cancellation of Application § 217.27 Effect of cancellation. When a person cancels an application the effect is the same as though an application was never filed. When an employee cancels his or her application, any application filed by the employee's spouse is also cancelled. However, a request...

A new Monte Carlo method for neutron noise calculations in the frequency domain

International Nuclear Information System (INIS)

Rouchon, Amélie; Zoia, Andrea; Sanchez, Richard

2017-01-01

Neutron noise equations, which are obtained by assuming small perturbations of macroscopic cross sections around a steady-state neutron field and by subsequently taking the Fourier transform in the frequency domain, have been usually solved by analytical techniques or by resorting to diffusion theory. A stochastic approach has been recently proposed in the literature by using particles with complex-valued weights and by applying a weight cancellation technique. We develop a new Monte Carlo algorithm that solves the transport neutron noise equations in the frequency domain. The stochastic method presented here relies on a modified collision operator and does not need any weight cancellation technique. In this paper, both Monte Carlo methods are compared with deterministic methods (diffusion in a slab geometry and transport in a simplified rod model) for several noise frequencies and for isotropic and anisotropic noise sources. Our stochastic method shows better performances in the frequency region of interest and is easier to implement because it relies upon the conventional algorithm for fixed-source problems.

An Adaptive Filter for the Removal of Drifting Sinusoidal Noise Without a Reference.

Science.gov (United States)

Kelly, John W; Siewiorek, Daniel P; Smailagic, Asim; Wang, Wei

2016-01-01

This paper presents a method for filtering sinusoidal noise with a variable bandwidth filter that is capable of tracking a sinusoid's drifting frequency. The method, which is based on the adaptive noise canceling (ANC) technique, will be referred to here as the adaptive sinusoid canceler (ASC). The ASC eliminates sinusoidal contamination by tracking its frequency and achieving a narrower bandwidth than typical notch filters. The detected frequency is used to digitally generate an internal reference instead of relying on an external one as ANC filters typically do. The filter's bandwidth adjusts to achieve faster and more accurate convergence. In this paper, the focus of the discussion and the data is physiological signals, specifically electrocorticographic (ECoG) neural data contaminated with power line noise, but the presented technique could be applicable to other recordings as well. On simulated data, the ASC was able to reliably track the noise's frequency, properly adjust its bandwidth, and outperform comparative methods including standard notch filters and an adaptive line enhancer. These results were reinforced by visual results obtained from real ECoG data. The ASC showed that it could be an effective method for increasing signal to noise ratio in the presence of drifting sinusoidal noise, which is of significant interest for biomedical applications.

An Adaptive Noise Cancellation System Based on Linear and Widely Linear Complex Valued Least Mean Square Algorithms for Removing Electrooculography Artifacts from Electroencephalography Signals

Directory of Open Access Journals (Sweden)

Engin Cemal MENGÜÇ

2018-03-01

Full Text Available In this study, an adaptive noise cancellation (ANC system based on linear and widely linear (WL complex valued least mean square (LMS algorithms is designed for removing electrooculography (EOG artifacts from electroencephalography (EEG signals. The real valued EOG and EEG signals (Fp1 and Fp2 given in dataset are primarily expressed as a complex valued signal in the complex domain. Then, using the proposed ANC system, the EOG artifacts are eliminated in the complex domain from the EEG signals. Expression of these signals in the complex domain allows us to remove EOG artifacts from two EEG channels simultaneously. Moreover, in this study, it has been shown that the complex valued EEG signal exhibits noncircular behavior, and in the case, the WL-CLMS algorithm enhances the performance of the ANC system compared to real-valued LMS and CLMS algorithms. Simulation results support the proposed approach.

Regression of environmental noise in LIGO data

International Nuclear Information System (INIS)

Tiwari, V; Klimenko, S; Mitselmakher, G; Necula, V; Drago, M; Prodi, G; Frolov, V; Yakushin, I; Re, V; Salemi, F; Vedovato, G

2015-01-01

We address the problem of noise regression in the output of gravitational-wave (GW) interferometers, using data from the physical environmental monitors (PEM). The objective of the regression analysis is to predict environmental noise in the GW channel from the PEM measurements. One of the most promising regression methods is based on the construction of Wiener–Kolmogorov (WK) filters. Using this method, the seismic noise cancellation from the LIGO GW channel has already been performed. In the presented approach the WK method has been extended, incorporating banks of Wiener filters in the time–frequency domain, multi-channel analysis and regulation schemes, which greatly enhance the versatility of the regression analysis. Also we present the first results on regression of the bi-coherent noise in the LIGO data. (paper)

48 CFR 552.238-73 - Cancellation.

Science.gov (United States)

2010-10-01

... may cancel this contract in whole or in part by providing written notice. The cancellation will take... elects to cancel this contract, the Government will not reimburse the minimum guarantee. (End of clause) ...

Beamspace Adaptive Beamforming for Hydrodynamic Towed Array Self-Noise Cancellation

National Research Council Canada - National Science Library

Premus, Vincent

2001-01-01

... against signal self-nulling associated with steering vector mismatch. Particular attention is paid to the definition of white noise gain as the metric that reflects the level of mainlobe adaptive nulling for an adaptive beamformer...

Beamspace Adaptive Beamforming for Hydrodynamic Towed Array Self-Noise Cancellation

National Research Council Canada - National Science Library

Premus, Vincent

2000-01-01

... against signal self-nulling associated with steering vector mismatch. Particular attention is paid to the definition of white noise gain as the metric that reflects the level of mainlobe adaptive nulling for an adaptive beamformer...

78 FR 47047 - Proposed Policy for Discontinuance of Certain Instrument Approach Procedures

Science.gov (United States)

2013-08-02

... the cancellation of certain Non-directional Beacon (NDB) and Very High Frequency (VHF) Omnidirectional... approach procedures. The FAA proposes specific criteria to guide the identification and selection of... selection of potential NDB and VOR procedures for cancellation. Once the criteria are established and the...

Source localization analysis using seismic noise data acquired in exploration geophysics

Science.gov (United States)

Roux, P.; Corciulo, M.; Campillo, M.; Dubuq, D.

2011-12-01

Passive monitoring using seismic noise data shows a growing interest at exploration scale. Recent studies demonstrated source localization capability using seismic noise cross-correlation at observation scales ranging from hundreds of kilometers to meters. In the context of exploration geophysics, classical localization methods using travel-time picking fail when no evident first arrivals can be detected. Likewise, methods based on the intensity decrease as a function of distance to the source also fail when the noise intensity decay gets more complicated than the power-law expected from geometrical spreading. We propose here an automatic procedure developed in ocean acoustics that permits to iteratively locate the dominant and secondary noise sources. The Matched-Field Processing (MFP) technique is based on the spatial coherence of raw noise signals acquired on a dense array of receivers in order to produce high-resolution source localizations. Standard MFP algorithms permits to locate the dominant noise source by matching the seismic noise Cross-Spectral Density Matrix (CSDM) with the equivalent CSDM calculated from a model and a surrogate source position that scans each position of a 3D grid below the array of seismic sensors. However, at exploration scale, the background noise is mostly dominated by surface noise sources related to human activities (roads, industrial platforms,..), which localization is of no interest for the monitoring of the hydrocarbon reservoir. In other words, the dominant noise sources mask lower-amplitude noise sources associated to the extraction process (in the volume). Their location is therefore difficult through standard MFP technique. The Multi-Rate Adaptative Beamforming (MRABF) is a further improvement of the MFP technique that permits to locate low-amplitude secondary noise sources using a projector matrix calculated from the eigen-value decomposition of the CSDM matrix. The MRABF approach aims at cancelling the contributions of

IIR digital filter design for powerline noise cancellation of ECG signal using arduino platform

Science.gov (United States)

Rahmatillah, Akif; Ataulkarim

2017-05-01

Powerline noise has been one of significant noises of Electrocardiogram (ECG) signal measurement. This noise is characterized by a sinusoidal signal which has 50 Hz of noise and 0.3 mV of maximum amplitude. This paper describes the design of IIR Notch filter design to reject a 50 Hz power line noise. IIR filter coefficients were calculated using pole placement method with three variations of band stop cut off frequencies of (49-51)Hz, (48 - 52)Hz, and (47 - 53)Hz. The algorithm and coefficients of filter were embedded to Arduino DUE (ARM 32 bit microcontroller). IIR notch filter designed has been able to reject power line noise with average square of error value of 0.225 on (49-51) Hz filter design and 0.2831 on (48 - 52)Hz filter design.

Wideband CMOS low noise amplifier including an active balun

NARCIS (Netherlands)

Blaakmeer, S.C.; Klumperink, Eric A.M.; Leenaerts, D.M.W.; Nauta, Bram

2007-01-01

An inductorless LNA with active balun is proposed for multi-standard radio applications between 100MHz and 6GHz [1]. It exploits a combination of a common-gate (CG) stage and an common-source (CS) stage with replica biasing to maximize balanced operation, while simultaneously canceling the noise and

A multichannel nonlinear adaptive noise canceller based on generalized FLANN for fetal ECG extraction

International Nuclear Information System (INIS)

Ma, Yaping; Wei, Guo; Sun, Jinwei; Xiao, Yegui

2016-01-01

In this paper, a multichannel nonlinear adaptive noise canceller (ANC) based on the generalized functional link artificial neural network (FLANN, GFLANN) is proposed for fetal electrocardiogram (FECG) extraction. A FIR filter and a GFLANN are equipped in parallel in each reference channel to respectively approximate the linearity and nonlinearity between the maternal ECG (MECG) and the composite abdominal ECG (AECG). A fast scheme is also introduced to reduce the computational cost of the FLANN and the GFLANN. Two (2) sets of ECG time sequences, one synthetic and one real, are utilized to demonstrate the improved effectiveness of the proposed nonlinear ANC. The real dataset is derived from the Physionet non-invasive FECG database (PNIFECGDB) including 55 multichannel recordings taken from a pregnant woman. It contains two subdatasets that consist of 14 and 8 recordings, respectively, with each recording being 90 s long. Simulation results based on these two datasets reveal, on the whole, that the proposed ANC does enjoy higher capability to deal with nonlinearity between MECG and AECG as compared with previous ANCs in terms of fetal QRS (FQRS)-related statistics and morphology of the extracted FECG waveforms. In particular, for the second real subdataset, the F1-measure results produced by the PCA-based template subtraction (TS pca ) technique and six (6) single-reference channel ANCs using LMS- and RLS-based FIR filters, Volterra filter, FLANN, GFLANN, and adaptive echo state neural network (ESN a ) are 92.47%, 93.70%, 94.07%, 94.22%, 94.90%, 94.90%, and 95.46%, respectively. The same F1-measure statistical results from five (5) multi-reference channel ANCs (LMS- and RLS-based FIR filters, Volterra filter, FLANN, and GFLANN) for the second real subdataset turn out to be 94.08%, 94.29%, 94.68%, 94.91%, and 94.96%, respectively. These results indicate that the ESN a and GFLANN perform best, with the ESN a being slightly better than the GFLANN but about four times

34 CFR 674.59 - Cancellation for military service.

Science.gov (United States)

2010-07-01

... 34 Education 3 2010-07-01 2010-07-01 false Cancellation for military service. 674.59 Section 674... Cancellation for military service. (a) Cancellation on a Defense loan. (1) An institution must cancel up to 50... cancellation rate is 121/2 percent of the original loan principal, plus the interest on the unpaid balance...

First Test of Fan Active Noise Control (ANC) Completed

Science.gov (United States)

2005-01-01

With the advent of ultrahigh-bypass engines, the space available for passive acoustic treatment is becoming more limited, whereas noise regulations are becoming more stringent. Active noise control (ANC) holds promise as a solution to this problem. It uses secondary (added) noise sources to reduce or eliminate the offending noise radiation. The first active noise control test on the low-speed fan test bed was a General Electric Company system designed to control either the exhaust or inlet fan tone. This system consists of a "ring source," an induct array of error microphones, and a control computer. Fan tone noise propagates in a duct in the form of spinning waves. These waves are detected by the microphone array, and the computer identifies their spinning structure. The computer then controls the "ring source" to generate waves that have the same spinning structure and amplitude, but 180 out of phase with the fan noise. This computer generated tone cancels the fan tone before it radiates from the duct and is heard in the far field. The "ring source" used in these tests is a cylindrical array of 16 flat-plate acoustic radiators that are driven by thin piezoceramic sheets bonded to their back surfaces. The resulting source can produce spinning waves up to mode 7 at levels high enough to cancel the fan tone. The control software is flexible enough to work on spinning mode orders from -6 to 6. In this test, the fan was configured to produce a tone of order 6. The complete modal (spinning and radial) structure of the tones was measured with two builtin sets of rotating microphone rakes. These rakes provide a measurement of the system performance independent from the control system error microphones. In addition, the far-field noise was measured with a semicircular array of 28 microphones. This test represents the first in a series of tests that demonstrate different active noise control concepts, each on a progressively more complicated modal structure. The tests are

Feasibility of Johnson Noise Thermometry based on Digital Signal Processing Techniques

International Nuclear Information System (INIS)

Hwang, In Koo; Kim, Yang Mo

2014-01-01

This paper presents an implementation strategy of noise thermometry based on a digital signal processing technique and demonstrates its feasibilities. A key factor in its development is how to extract the small thermal noise signal from other noises, for example, random noise from amplifiers and continuous electromagnetic interference from the environment. The proposed system consists of two identical amplifiers and uses a cross correlation function to cancel the random noise of the amplifiers. Then, the external interference noises are eliminated by discriminating the difference in the peaks between the thermal signal and external noise. The gain of the amplifiers is estimated by injecting an already known pilot signal. The experimental simulation results of signal processing methods have demonstrated that the proposed approach is an effective method in eliminating an external noise signal and performing gain correction for development of the thermometry

Lateralization of noise bursts in interaurally correlated or uncorrelated background noise using interaural level differences.

Science.gov (United States)

Reed, Darrin K; van de Par, Steven

2015-10-01

The interaural level difference (ILD) of a lateralized target source may be effectively reduced when the target is presented together with background noise containing zero ILD. It is not certain whether listeners perceive a position congruent with the reduced ILD or the actual target ILD in a lateralization task. Two sets of behavioral experiments revealed that many listeners perceived a position at or even larger than that corresponding to the presented target ILD when a temporal onset/offset asynchrony between the broadband target and the broadband background noise was present. When no temporal asynchrony was present, however, the perceived lateral position indicated a dependency on the coherence of the background noise for several listeners. With interaurally correlated background noise, listeners reported a reduced ILD resulting from the combined target and background noise stimulus. In contrast, several of the listeners made a reasonable estimate of the position corresponding to the target ILD for interaurally uncorrelated, broadband, background noise. No obvious difference in performance was seen between low- or high-frequency stimuli. Extension of a weighting template to the output of a standard equalization-cancellation model was shown to remove a lateral bias on the predicted target ILD resulting from the presence of background noise. Provided that an appropriate weighting template is applied based on knowledge of the background noise coherence, good prediction of the behavioral data is possible.

Electrically evoked compound action potentials artefact rejection by independent component analysis: procedure automation.

Science.gov (United States)

Akhoun, Idrick; McKay, Colette; El-Deredy, Wael

2015-01-15

Independent-components-analysis (ICA) successfully separated electrically-evoked compound action potentials (ECAPs) from the stimulation artefact and noise (ECAP-ICA, Akhoun et al., 2013). This paper shows how to automate the ECAP-ICA artefact cancellation process. Raw-ECAPs without artefact rejection were consecutively recorded for each stimulation condition from at least 8 intra-cochlear electrodes. Firstly, amplifier-saturated recordings were discarded, and the data from different stimulus conditions (different current-levels) were concatenated temporally. The key aspect of the automation procedure was the sequential deductive source categorisation after ICA was applied with a restriction to 4 sources. The stereotypical aspect of the 4 sources enables their automatic classification as two artefact components, a noise and the sought ECAP based on theoretical and empirical considerations. The automatic procedure was tested using 8 cochlear implant (CI) users and one to four stimulus electrodes. The artefact and noise sources were successively identified and discarded, leaving the ECAP as the remaining source. The automated ECAP-ICA procedure successfully extracted the correct ECAPs compared to standard clinical forward masking paradigm in 22 out of 26 cases. ECAP-ICA does not require extracting the ECAP from a combination of distinct buffers as it is the case with regular methods. It is an alternative that does not have the possible bias of traditional artefact rejections such as alternate-polarity or forward-masking paradigms. The ECAP-ICA procedure bears clinical relevance, for example as the artefact rejection sub-module of automated ECAP-threshold detection techniques, which are common features of CI clinical fitting software. Copyright © 2014. Published by Elsevier B.V.

Noise in position measurement by centroid calculation

International Nuclear Information System (INIS)

Volkov, P.

1996-01-01

The position of a particle trajectory in a gaseous (or semiconductor) detector can be measured by calculating the centroid of the induced charge on the cathode plane. The charge amplifiers attached to each cathode strip introduce noise which is added to the signal. This noise broadens the position resolution line. Our article gives an analytical tool to estimate the resolution broadening due to the noise per strip and the number of strips involved in the centroid calculation. It is shown that the position resolution increases faster than the square root of the number of strips involved. We also consider the consequence of added interstrip capacitors, intended to diminish the differential nonlinearity. It is shown that the position error increases slower than linearly with the interstrip capacities, due to the cancellation of correlated noise. The estimation we give, can be applied to calculations of position broadening other than the centroid finding. (orig.)

Application of Adaptive Noise Cancellation for Anti-Vibration in Yield Monitor

Directory of Open Access Journals (Sweden)

Yan LI

2014-04-01

Full Text Available In the process of grain harvest, yield monitor system acquires real-time spatial distribution information of crop yield to provide important basis of decision-making for subsequent assignments of precision agriculture. The measurement accuracy has been seriously affected by Combine working vibration. Based on an innovative test platform of wheat combine harvester for yield monitor, well simulate the working vibration at the field situation; impact-based grain flow sensor with the structure of dual-parallel-beams as test terminals and using the NI (National Instrument data acquisition card to acquire signals; grain impacted frequency as fundamental frequency to process harmonic extraction, and for extracted signals, applied the improved LMS adaptive algorithm to interference cancellation, aim to eliminate interference cased by working vibration. The comparative experiment show that the maximum relative error less than 2 % under the proposed method and proved that the proposed algorithm in this paper is effective.

Interior noise analysis of a construction equipment cabin based on airborne and structure-borne noise predictions

Energy Technology Data Exchange (ETDEWEB)

Kim, Sung Hee; Hong, Suk Yoon [Seoul National University, Seoul (Korea, Republic of); Song, Jee Hun [Chonnam National University, Gwangju (Korea, Republic of); Joo, Won Ho [Hyundai Heavy Industries Co. Ltd, Ulsan (Korea, Republic of)

2012-04-15

Noise from construction equipment affects not only surrounding residents, but also the operators of the machines. Noise that affects drivers must be evaluated during the preliminary design stage. This paper suggests an interior noise analysis procedure for construction equipment cabins. The analysis procedure, which can be used in the preliminary design stage, was investigated for airborne and structure borne noise. The total interior noise of a cabin was predicted from the airborne noise analysis and structure-borne noise analysis. The analysis procedure consists of four steps: modeling, vibration analysis, acoustic analysis and total interior noise analysis. A mesh model of a cabin for numerical analysis was made at the modeling step. At the vibration analysis step, the mesh model was verified and modal analysis and frequency response analysis are performed. At the acoustic analysis step, the vibration results from the vibration analysis step were used as initial values for radiated noise analysis and noise reduction analysis. Finally, the total cabin interior noise was predicted using the acoustic results from the acoustic analysis step. Each step was applied to a cabin of a middle-sized excavator and verified by comparison with measured data. The cabin interior noise of a middle-sized wheel loader and a large-sized forklift were predicted using the analysis procedure of the four steps and were compared with measured data. The interior noise analysis procedure of construction equipment cabins is expected to be used during the preliminary design stage.

Interior noise analysis of a construction equipment cabin based on airborne and structure-borne noise predictions

International Nuclear Information System (INIS)

Kim, Sung Hee; Hong, Suk Yoon; Song, Jee Hun; Joo, Won Ho

2012-01-01

Noise from construction equipment affects not only surrounding residents, but also the operators of the machines. Noise that affects drivers must be evaluated during the preliminary design stage. This paper suggests an interior noise analysis procedure for construction equipment cabins. The analysis procedure, which can be used in the preliminary design stage, was investigated for airborne and structure borne noise. The total interior noise of a cabin was predicted from the airborne noise analysis and structure-borne noise analysis. The analysis procedure consists of four steps: modeling, vibration analysis, acoustic analysis and total interior noise analysis. A mesh model of a cabin for numerical analysis was made at the modeling step. At the vibration analysis step, the mesh model was verified and modal analysis and frequency response analysis are performed. At the acoustic analysis step, the vibration results from the vibration analysis step were used as initial values for radiated noise analysis and noise reduction analysis. Finally, the total cabin interior noise was predicted using the acoustic results from the acoustic analysis step. Each step was applied to a cabin of a middle-sized excavator and verified by comparison with measured data. The cabin interior noise of a middle-sized wheel loader and a large-sized forklift were predicted using the analysis procedure of the four steps and were compared with measured data. The interior noise analysis procedure of construction equipment cabins is expected to be used during the preliminary design stage

Patient experiences with interventions to reduce surgery cancellations

DEFF Research Database (Denmark)

Hovlid, Einar; von Plessen, Christian; Haug, Kjell

2013-01-01

The cancellation of planned surgery harms patients, increases waiting times and wastes scarce health resources. Previous studies have evaluated interventions to reduce cancellations from medical and management perspectives; these have focused on cost, length of stay, improved efficiency......, and reduced post-operative complications. In our case a hospital had experienced high cancellation rates and therefore redesigned their pathway for elective surgery to reduce cancelations. We studied how patients experienced interventions to reduce cancellations....

Modulator noise suppression in the LISA time-delay interferometric combinations

International Nuclear Information System (INIS)

Tinto, Massimo; Armstrong, J W; Estabrook, Frank B

2008-01-01

Laser Interferometer Space Antenna (LISA) is a mission to detect and study low-frequency cosmic gravitational radiation through its influence on the phases of six modulated laser beams exchanged between three remote spacecraft. We previously showed how the measurements of some 18 time series of relative frequency or phase shifts could be combined (1) to cancel the phase noise of the lasers, (2) to cancel the Doppler fluctuations due to non-inertial motions of the six optical benches and (3) to remove the phase noise of the onboard reference oscillators required to track the photodetector fringes, all the while preserving signals from passing gravitational waves. Here we analyze the effect of the additional noise due to the optical modulators used for removing the phase fluctuations of the onboard reference oscillators. We use the recently measured noise spectrum of an individual modulator (Klipstein et al 2006 Proc. 6th Int. LISA Symp. (Greenbelt, MA) (AIP Conf. Proc. vol 873) ed S M Merkowitz and J C Livas pp 19-23) to quantify the contribution of modulator noise to the first and second-generation time-delay interferometric (TDI) combinations as a function of the modulation frequency. We show that modulator noise can be made smaller than the expected proof-mass acceleration and optical-path noises if the modulation frequencies are larger than ∼682 MHz in the case of the unequal-arm Michelson TDI combination X 1 , ∼ 1.08 GHz for the Sagnac TDI combination α 1 , and ∼706 MHz for the symmetrical Sagnac TDI combination ζ 1 . These modulation frequencies are substantially smaller than previously estimated and may lead to less stringent requirements on the LISA's oscillator noise calibration subsystem. The measurements in Klipstein et al were performed in a laboratory experiment for a range of modulation frequencies, but we emphasize that, for the reference oscillator noise calibration algorithm to work, the modulation frequencies must be equal to the

Group study of an "undercover" test for visuospatial neglect: invisible cancellation can reveal more neglect than standard cancellation.

Science.gov (United States)

Wojciulik, E; Rorden, C; Clarke, K; Husain, M; Driver, J

2004-09-01

Visual neglect is a relatively common deficit after brain damage, particularly strokes. Cancellation tests provide standard clinical measures of neglect severity and deficits in daily life. A recent single-case study introduced a new variation on standard cancellation. Instead of making a visible mark on each target found, the patient made invisible marks (recorded with carbon paper underneath, for later scoring). Such invisible cancellation was found to reveal more neglect than cancellation with visible marks. Here we test the generality of this. Twenty three successive cases with suspected neglect each performed cancellation with visible or invisible marks. Neglect of contralesional targets was more pronounced with invisible marks. Indeed, about half of the patients only showed neglect in this version. For cases showing more neglect with invisible marks, stronger neglect of contralesional targets correlated with more revisits to ipsilesional targets for making additional invisible marks upon them. These results indicate that cancellation with invisible marks can reveal more neglect than standard cancellation with visible marks, while still providing a practical bedside test. Our observations may be consistent with recent proposals that demands on spatial working memory (required to keep track of previously found items only when marked invisibly) can exacerbate spatial neglect.

Pump-probe differencing technique for cavity-enhanced, noise-canceling saturation laser spectroscopy.

Science.gov (United States)

de Vine, Glenn; McClelland, David E; Gray, Malcolm B; Close, John D

2005-05-15

We present an experimental technique that permits mechanical-noise-free, cavity-enhanced frequency measurements of an atomic transition and its hyperfine structure. We employ the 532-nm frequency-doubled output from a Nd:YAG laser and an iodine vapor cell. The cell is placed in a folded ring cavity (FRC) with counterpropagating pump and probe beams. The FRC is locked with the Pound-Drever-Hall technique. Mechanical noise is rejected by differencing the pump and probe signals. In addition, this differenced error signal provides a sensitive measure of differential nonlinearity within the FRC.

MEMS microphone innovations towards high signal to noise ratios (Conference Presentation) (Plenary Presentation)

Science.gov (United States)

Dehé, Alfons

2017-06-01

After decades of research and more than ten years of successful production in very high volumes Silicon MEMS microphones are mature and unbeatable in form factor and robustness. Audio applications such as video, noise cancellation and speech recognition are key differentiators in smart phones. Microphones with low self-noise enable those functions. Backplate-free microphones enter the signal to noise ratios above 70dB(A). This talk will describe state of the art MEMS technology of Infineon Technologies. An outlook on future technologies such as the comb sensor microphone will be given.

An alternative method for noise analysis using pixel variance as part of quality control procedures on digital mammography systems

International Nuclear Information System (INIS)

Bouwman, R; Broeders, M; Van Engen, R; Young, K; Lazzari, B; Ravaglia, V

2009-01-01

According to the European Guidelines for quality assured breast cancer screening and diagnosis, noise analysis is one of the measurements that needs to be performed as part of quality control procedures on digital mammography systems. However, the method recommended in the European Guidelines does not discriminate sufficiently between systems with and without additional noise besides quantum noise. This paper attempts to give an alternative and relatively simple method for noise analysis which can divide noise into electronic noise, structured noise and quantum noise. Quantum noise needs to be the dominant noise source in clinical images for optimal performance of a digital mammography system, and therefore the amount of electronic and structured noise should be minimal. For several digital mammography systems, the noise was separated into components based on the measured pixel value, standard deviation (SD) of the image and the detector entrance dose. The results showed that differences between systems exist. Our findings confirm that the proposed method is able to discriminate systems based on their noise performance and is able to detect possible quality problems. Therefore, we suggest to replace the current method for noise analysis as described in the European Guidelines by the alternative method described in this paper.

Contributions to noise in the data readout for Trigger Tracker in the LHCb Experiment

CERN Document Server

Bieler, Ueli

This thesis reports the analysis of contributions to noise in the data readout for Trigger Tracker in the LHCb experiment. Measurements have shown that some specific data channels have more noise than the others. This additional contributions to noise cannot be explained by basic electronic noise principles of the detector but by noise sources in the readout chain. The focus is on the channels near the header. Because of a crosstalk effect in the readout electronics the pseudo- digital header affects the close-by analog data channels. Therefore the correlation between the header and the data channels is studied precisely by self-made analysis tools in order to develop an algorithm that cancels the crosstalk contribution to noise. Thanks the algorithm the noise can be reduced efficiently.

Unexpected role of excess noise in spontaneous emission

International Nuclear Information System (INIS)

Lamprecht, C.; Ritsch, H.

2002-01-01

A single inverted two-level atom is used as a theoretical model for a quantum noise detector to investigate fundamental properties of excess noise in an unstable optical resonator. For a symmetric unstable spherical mirror cavity, we develop an analytic quantum description of the field in terms of a complete set of normalizable biorthogonal quasimodes and adjoint modes. Including the interaction with a single two-level atom leads to a description analogous to the Jaynes-Cummings model with modified coupling constants. One finds a strong position and geometry-dependent atomic decay probability proportional to the square root √(K) of the excess noise factor K at the cavity center. Introducing an additional homogeneous gain one recovers the K-fold emission enhancement that has been predicted before for the linewidth of an unstable cavity laser. We find that excess noise may be viewed as a spatial redistribution of the field quantum noise inside the resonator. Taking a position average of the atomic decay rate over the cavity volume leads to a cancellation of the excess noise enhancement

Hearing loss associated with repeated MRI acquisition procedure-related acoustic noise exposure: an occupational cohort study

NARCIS (Netherlands)

Bongers, Suzan; Slottje, Pauline; Kromhout, Hans

2017-01-01

OBJECTIVE: To study the effects of repeated exposure to MRI-related acoustic noise during image acquisition procedures (scans) on hearing. METHODS: A retrospective occupational cohort study was performed among workers of an MRI manufacturing facility (n=474). Longitudinal audiometry data from the

Theory of the cancellation of 4-photon resonances by an off-resonance 3-photon cancellation

DEFF Research Database (Denmark)

Elk, M.; Lambropoulos, P.; Tang, X.

1992-01-01

We present a complete account of our recent work [Phys. Rev. A 44, 31 (1991)] in which we investigate the theory of cancellation by interference between the absorption of three fundamental laser photons and one third-harmonic photon. The theory is formulated in terms of the density matrix so...... as to take detunings, dephasing, and laser bandwidth into account. The result is a theory of cancellation for finite detuning that explains how four-photon resonances can be canceled by a three-photon mechanism if there is an atomic level at near-three-photon resonance. The treatment is extended to focused...

49 CFR 40.273 - What is the effect of a cancelled alcohol test?

Science.gov (United States)

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false What is the effect of a cancelled alcohol test? 40.273 Section 40.273 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Problems in Alcohol Testing § 40.273 What is the...

Wavelet-LMS algorithm-based echo cancellers

Science.gov (United States)

Seetharaman, Lalith K.; Rao, Sathyanarayana S.

2002-12-01

This paper presents Echo Cancellers based on the Wavelet-LMS Algorithm. The performance of the Least Mean Square Algorithm in Wavelet transform domain is observed and its application in Echo cancellation is analyzed. The Widrow-Hoff Least Mean Square Algorithm is most widely used algorithm for Adaptive filters that function as Echo Cancellers. The present day communication signals are widely non-stationary in nature and some errors crop up when Least Mean Square Algorithm is used for the Echo Cancellers handling such signals. The analysis of non-stationary signals often involves a compromise between how well transitions or discontinuities can be located. The multi-scale or multi-resolution of signal analysis, which is the essence of wavelet transform, makes Wavelets popular in non-stationary signal analysis. In this paper, we present a Wavelet-LMS algorithm wherein the wavelet coefficients of a signal are modified adaptively using the Least Mean Square Algorithm and then reconstructed to give an Echo-free signal. The Echo Canceller based on this Algorithm is found to have a better convergence and a comparatively lesser MSE (Mean Square error).

Optimization of the GOES-1 Imagers radiometric accuracy: Drift and 1/f noise suppression

International Nuclear Information System (INIS)

Bremer, J.C.; Comeyne, G.J. III

1994-01-01

The raw output of many scanning radiometers is a small, rapidly varying signal superimposed on a large background that varies more slowly, due to thermal drifts and 1/f noise. To isolate the signal, it is necessary to perform a differential measurement: measure a known reference and subtract it from each of the raw outputs, canceling the common-mode background. Calibration is also a differential measurement: the difference between two outputs is divided by the difference between the two known references that produced them to determine the gain. The GOES-I Imager views space as its background subtraction reference and a full-aperture blackbody as its second reference for calibration. The background suppression efficiency of a differential measurement algorithm depends on its timing. The Imager measures space references before and after each scan line and performs interpolated background subtraction: a unique, linearly weighted average of the two references is subtracted from each scene sample in that line, canceling both constant bias and linear drift. One model quantifies the Gaussian noise and 1/f noise terms in the noise equivalent bandwidth, which is minimized to optimize the algorithm. The authors have obtained excellent agreement between the analytical predictions and Monte Carlo computer simulations

Low-noise detector and amplifier design for 100 ns direct detection CO{sub 2} LIDAR receiver

Energy Technology Data Exchange (ETDEWEB)

Cafferty, M.M.; Cooke, B.J.; Laubscher, B.E.; Olivas, N.L.; Fuller, K.

1997-06-01

The development and test results of a prototype detector/amplifier design for a background limited, pulsed 100 ns, 10--100 kHz repetition rate LIDAR/DIAL receiver system are presented. Design objectives include near-matched filter detection of received pulse amplitude and round trip time-of-flight, and the elimination of excess correlated detector/amplifier noise for optimal pulse averaging. A novel pole-zero cancellation amplifier, coupled with a state-of-the-art SBRC (Santa Barbara Research Center) infrared detector was implemented to meet design objectives. The pole-zero cancellation amplifier utilizes a tunable, pseudo-matched filter technique to match the width of the laser pulse to the shaping time of the filter for optimal SNR performance. Low frequency correlated noise, (l/f and drift noise) is rejected through a second order high gain feedback loop. The amplifier also employs an active detector bias stage minimizing detector drift. Experimental results will be provided that demonstrate near-background limited, 100 ns pulse detection performance given a 8.5--11.5 {micro}m (300 K B.B.) radiant background, with the total noise floor spectrally white for optimal pulse averaging efficiency.

Nuclear plant cancellations: causes, costs, and consequences

International Nuclear Information System (INIS)

1983-04-01

This study was commissioned in order to help quantify the effects of nuclear plant cancellations on the Nation's electricity prices. This report presents a historical overview of nuclear plant cancellations through 1982, the costs associated with those cancellations, and the reasons that the projects were terminated. A survey is presented of the precedents for regulatory treatment of the costs, the specific methods of cost recovery that were adopted, and the impacts of these decisions upon ratepayers, utility stockholders, and taxpayers. Finally, the report identifies a series of other nuclear plants that remain at risk of canellation in the future, principally as a result of similar demand, finance, or regulatory problems cited as causes of cancellation in the past. The costs associated with these potential cancellations are estimated, along with their regional distributions, and likely methods of cost recovery are suggested

An improved affine projection algorithm for active noise cancellation

Science.gov (United States)

Zhang, Congyan; Wang, Mingjiang; Han, Yufei; Sun, Yunzhuo

2017-08-01

Affine projection algorithm is a signal reuse algorithm, and it has a good convergence rate compared to other traditional adaptive filtering algorithm. There are two factors that affect the performance of the algorithm, which are step factor and the projection length. In the paper, we propose a new variable step size affine projection algorithm (VSS-APA). It dynamically changes the step size according to certain rules, so that it can get smaller steady-state error and faster convergence speed. Simulation results can prove that its performance is superior to the traditional affine projection algorithm and in the active noise control (ANC) applications, the new algorithm can get very good results.

An Innovative Procedure for the Rolling Noise Evaluation

Directory of Open Access Journals (Sweden)

Viscardi Massimo

2016-01-01

Full Text Available Noise is often generated by pressure changes in the air induced by mechanical vibrations. The study of these phenomena is known as structural acoustics or, in a more fashionable way, virboacoustics. Vibroacoustics is the study of the mechanical waves in structures and how they interact with, and radiate into, adjacent media. In railway the most important noise source, based on fluid and structure interaction is the rolling noise. The aim of the paper is the development and implementation of a numerical method for the rail decay rate and combined roughness calculation according to the FprCEN/TR 16891:2015 and a subsequent evaluation of the excess noise level in accordance with the ISO/FDIS 3095: 2013. The tool, as a final results, will make possible the evaluation of the rail parameters without the involvement of long and expensive test campaign based on classical roughness measurement methods and will permit the compensation of the roughness induced excess noise level for a comparative comprehension of the acoustic experimental data.

49 CFR 40.207 - What is the effect of a cancelled drug test?

Science.gov (United States)

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false What is the effect of a cancelled drug test? 40.207 Section 40.207 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Problems in Drug Tests § 40.207 What is the effect of...

Active cancellation - A means to zero dead-time pulse EPR.

Science.gov (United States)

Franck, John M; Barnes, Ryan P; Keller, Timothy J; Kaufmann, Thomas; Han, Songi

2015-12-01

The necessary resonator employed in pulse electron paramagnetic resonance (EPR) rings after the excitation pulse and creates a finite detector dead-time that ultimately prevents the detection of signal from fast relaxing spin systems, hindering the application of pulse EPR to room temperature measurements of interesting chemical or biological systems. We employ a recently available high bandwidth arbitrary waveform generator (AWG) to produce a cancellation pulse that precisely destructively interferes with the resonant cavity ring-down. We find that we can faithfully detect EPR signal at all times immediately after, as well as during, the excitation pulse. This is a proof of concept study showcasing the capability of AWG pulses to precisely cancel out the resonator ring-down, and allow for the detection of EPR signal during the pulse itself, as well as the dead-time of the resonator. However, the applicability of this approach to conventional EPR experiments is not immediate, as it hinges on either (1) the availability of low-noise microwave sources and amplifiers to produce the necessary power for pulse EPR experiment or (2) the availability of very high conversion factor micro coil resonators that allow for pulse EPR experiments at modest microwave power. Copyright © 2015 Elsevier Inc. All rights reserved.

Voluntary Cancellation of a Pesticide Product or Use

Science.gov (United States)

A registrant can cancel the registration of a pesticide product or cancel a use from the product’s label at any time as stated in Section 6(f) of FIFRA. Learn how to request a voluntary cancellation or use deletion.

20 CFR 217.26 - How to cancel an application.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false How to cancel an application. 217.26 Section... APPLICATION FOR ANNUITY OR LUMP SUM Cancellation of Application § 217.26 How to cancel an application. An application may be cancelled under the following conditions: (a) Before an annuity is awarded. The application...

Balanced detection for self-mixing interferometry to improve signal-to-noise ratio

Science.gov (United States)

Zhao, Changming; Norgia, Michele; Li, Kun

2018-01-01

We apply balanced detection to self-mixing interferometry for displacement and vibration measurement, using two photodiodes for implementing a differential acquisition. The method is based on the phase opposition of the self-mixing signal measured between the two laser diode facet outputs. The balanced signal obtained by enlarging the self-mixing signal, also by canceling of the common-due noises mainly due to disturbances on laser supply and transimpedance amplifier. Experimental results demonstrate the signal-to-noise ratio significantly improves, with almost twice signals enhancement and more than half noise decreasing. This method allows for more robust, longer-distance measurement systems, especially using fringe-counting.

Performance comparison of optical interference cancellation system architectures.

Science.gov (United States)

Lu, Maddie; Chang, Matt; Deng, Yanhua; Prucnal, Paul R

2013-04-10

The performance of three optics-based interference cancellation systems are compared and contrasted with each other, and with traditional electronic techniques for interference cancellation. The comparison is based on a set of common performance metrics that we have developed for this purpose. It is shown that thorough evaluation of our optical approaches takes into account the traditional notions of depth of cancellation and dynamic range, along with notions of link loss and uniformity of cancellation. Our evaluation shows that our use of optical components affords performance that surpasses traditional electronic approaches, and that the optimal choice for an optical interference canceller requires taking into account the performance metrics discussed in this paper.

New hybrid technique for impulsive noise suppression in OFDM systems

International Nuclear Information System (INIS)

Mirza, A.; Zeb, A.; Sheikh, S.A.

2017-01-01

In this paper, a new hybrid technique employing RS (Reed Solomon) coding and adaptive filter for impulsive noise suppression in OFDM (Orthogonal Frequency Division Multiplexing) systems is presented. Adaptive filter creates a more accurate estimate of the original OFDM signal after impulsive noise cancellation. The residual impulsive noise is further mitigated by RS decoder in the second stage of proposed technique. Three members of adaptive filters family i.e. NLMS (Normalized Least Mean Square) algorithm, RLS (Recursive Least Square) algorithm and Bhagyashri algorithm are tested with RS decoder in the proposed hybrid technique. Furthermore, the results in terms of steady state MSE (Mean Square Error) reduction, BER (Bit Error Rate) improvement and SNR (Signal to Noise Ratio) enhancement confirm the effectiveness of the proposed dual faceted technique when compared with the recently reported techniques in literature. (author)

Active Noise Control Using Modified FsLMS and Hybrid PSOFF Algorithm

Directory of Open Access Journals (Sweden)

Ranjan Walia

2018-04-01

Full Text Available Active noise control is an efficient technique for noise cancellation of the system, which has been defined in this paper with the aid of Modified Filtered-s Least Mean Square (MFsLMS algorithm. The Hybrid Particle Swarm Optimization and Firefly (HPSOFF algorithm are used to identify the stability factor of the MFsLMS algorithm. The computational difficulty of the modified algorithm is reduced when compared with the original Filtered-s Least Mean Square (FsLMS algorithm. The noise sources are removed from the signal and it is compared with the existing FsLMS algorithm. The performance of the system is established with the normalized mean square error for two different types of noises. The proposed method has also been compared with the existing algorithms for the same purposes.

Elective surgery cancelation on day of surgery: An endless dilemma

Directory of Open Access Journals (Sweden)

A Fayed

2016-01-01

Full Text Available Background: Cancelation of surgery is a constant agonizing dilemma for nearly all healthcare services that has been intensively investigated to find out its roots, consequences, and possible solutions. The rates of cancelation of surgery vary between centers and more so among surgical specialties with numerous reasons standing behind this phenomenon. Patients and Methods: In the current study, analysis of monthly cancelation rates from January 2009 to December 2012, and assessment of establishing new operating rooms (ORs using statistical process control charts was conducted. A detailed review of a total of 1813 cases canceled on the day of surgery from January to December 2012, to examine the various reasons of cancelation among surgical specialties. Results: The average cancelation rate was 11.1%, which dropped to 9.0% after launching of new theaters. Four reasons explained about 80% of cancelations; Patients "no show" was the leading cause of cancelation (27%. One-fourth of cancelations (24.3% were due to the need for further optimization, and the third most prominent cause of cancelation was a lack of OR time (19.5%. Unavailability of staff/equipment/implants accounted for only 0.7% of cancelations. The "no show" was the most common cause of cancelation among all surgical specialties ranging from 21% for plastic surgery to 32% in ophthalmic surgeries. Conclusion: It was confirmed that there is a unique profile of cancelation of surgery problem for every institute, an extension of infrastructure may not be the only solution. Control charts helped to enhance the general picture and are functional in monitoring and evaluating changes in the cancelation of surgery.

Procedure to derive analytical models for microwave noise performances of Si/SiGe:C and InP/InGaAs heterojunction bipolar transistors

International Nuclear Information System (INIS)

Ramirez-Garcia, E; Enciso-Aguilar, M A; Aniel, F P; Zerounian, N

2013-01-01

We present a useful procedure to derive simplified expressions to model the minimum noise factor and the equivalent noise resistance of Si/SiGe:C and InP/InGaAs heterojunction bipolar transistors (HBTs). An acceptable agreement between models and measurements at operation frequencies up to 18 GHz and at several bias points is demonstrated. The development procedure includes all the significant microwave noise sources of the HBTs. These relations should be useful to model F min and R n for state-of-the-art IV-IV and III–V HBTs. The method is the first step to derive noise analyses formulas valid for operation frequencies near the unitary current gain frequency (f T ); however, to achieve this goal a necessary condition is to have access to HFN measurements up to this frequency regime. (paper)

20 CFR 217.25 - Who may cancel an application.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Who may cancel an application. 217.25 Section... APPLICATION FOR ANNUITY OR LUMP SUM Cancellation of Application § 217.25 Who may cancel an application. An application may be cancelled by the claimant or a person described in § 217.17. If the claimant is deceased...

40 CFR 152.99 - Petitions to cancel registration.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Petitions to cancel registration. 152... Submitters' Rights § 152.99 Petitions to cancel registration. An original data submitter may petition the Agency to deny or cancel the registration of a product in accordance with this section if he has...

Does ambient noise or hypobaric atmosphere influence olfactory and gustatory function?

Science.gov (United States)

Rahne, Torsten; Köppke, Robert; Nehring, Michael; Plontke, Stefan K; Fischer, Hans-Georg

2018-01-01

Multidimensional food perception is based mainly on gustatory and olfactory function. Recent research has demonstrated that hypobaric pressure impairs gustatory function and that background noise or distracting auditory stimulation impairs olfactory function. Using a hypobaric chamber, the odor identification, discrimination, and thresholds as well as taste identification and threshold scores were measured in 16 healthy male volunteers under normal and hypobaric (6380 ft) conditions using clinically validated tests. In both conditions, background noise was either canceled out or replaced by white noise presentation (70 dB sound pressure level). Olfactory sensitivity for n-butanol and gustatory sensitivity were impaired in a hypobaric atmosphere. White noise did not influence the odor test results. White noise stimulation impaired sensitivity for sour and sweet but not for bitter or salty tastants. We conclude that hypobaric or noisy environments could impair gustatory and olfactory sensitivity selectively for particular tastants and odorants.

Using Comics to Communicate Legal Contract Cancellation

OpenAIRE

Marietjie Botes

2017-01-01

This article investigates how comics can be used to adequately communicate the correct process of contract cancellation and whether comics can enhance understanding of the legal process. A survey of pre-owned vehicle buyers of various levels of education in Pretoria, South Africa found that when comics are used to communicate contract cancellation, a significant increase in the comprehension of the legal cancellation process occurs. The results may influence how contracting parties may choose...

Photonic-Enabled RF Canceller with Tunable Time-Delay Taps

Science.gov (United States)

2016-12-05

Photonic -Enabled RF Canceller with Tunable Time-Delay Taps Kenneth E. Kolodziej, Sivasubramaniam Yegnanarayanan, Bradley T. Perry MIT Lincoln...canceller design that uses photonics and a vector modulator architecture to provide a high number of canceller taps with tunable time-delays, which allow...microwave photonics , RF cancellation. I. INTRODUCTION In-Band Full-Duplex (IBFD) technologies are being consid- ered for 5th generation (5G) wireless

Development of a low-noise, two-dimensional amplifier array

International Nuclear Information System (INIS)

Kishishita, Tetsuichi; Ikeda, Hirokazu; Sakumura, Takuto; Tamura, Ken-ichi; Takahashi, Tadayuki

2009-01-01

This paper describes the recent development of a low-noise, two-dimensional analog front-end ASIC for hybrid pixel imaging detectors. Based on the Open-IP LSI project, the ASIC is designed to meet a low-noise requirement of better than 100e - (rms) with self-triggering capability. The ASIC is intended for the readout of pixel sensors utilizing silicon (Si) and cadmium telluride (CdTe) as detector materials for spectroscopic imaging observations in the X-ray and gamma-ray regions. The readout chip consists of a 4x4 matrix of identical 270μmx270μm pixel cells and was implemented with TSMC 0.35-μm CMOS technology. Each pixel cell contains a charge-sensitive amplifier, pole-zero cancellation circuit, shaper, comparator, and peak hold circuit. Preliminary testing of the ASIC achieved an 88e - (rms) equivalent noise charge and a 25e - /pF noise slope with power consumption of 150μW per pixel.

RATES OF PHOTOSPHERIC MAGNETIC FLUX CANCELLATION MEASURED WITH HINODE

International Nuclear Information System (INIS)

Park, Soyoung; Chae, Jongchul; Litvinenko, Yuri E.

2009-01-01

Photospheric magnetic flux cancellation on the Sun is generally believed to be caused by magnetic reconnection occurring in the low solar atmosphere. Individual canceling magnetic features are observationally characterized by the rate of flux cancellation. The specific cancellation rate, defined as the rate of flux cancellation divided by the interface length, gives an accurate estimate of the electric field in the reconnecting current sheet. We have determined the specific cancellation rate using the magnetograms taken by the Solar Optical Telescope (SOT) aboard the Hinode satellite. The specific rates determined with SOT turned out to be systematically higher than those based on the data taken by the Michelson Doppler Imager (MDI) aboard the Solar and Heliospheric Observatory. The median value of the specific cancellation rate was found to be 8 x 10 6 G cm s -1 -a value four times that obtained from the MDI data. This big difference is mainly due to a higher angular resolution and better sensitivity of the SOT, resulting in magnetic fluxes up to five times larger than those obtained from the MDI. The higher rates of flux cancellation correspond to either faster inflows or stronger magnetic fields of the reconnection inflow region, which may have important consequences for the physics of photospheric magnetic reconnection.

Frequency tracking and variable bandwidth for line noise filtering without a reference.

Science.gov (United States)

Kelly, John W; Collinger, Jennifer L; Degenhart, Alan D; Siewiorek, Daniel P; Smailagic, Asim; Wang, Wei

2011-01-01

This paper presents a method for filtering line noise using an adaptive noise canceling (ANC) technique. This method effectively eliminates the sinusoidal contamination while achieving a narrower bandwidth than typical notch filters and without relying on the availability of a noise reference signal as ANC methods normally do. A sinusoidal reference is instead digitally generated and the filter efficiently tracks the power line frequency, which drifts around a known value. The filter's learning rate is also automatically adjusted to achieve faster and more accurate convergence and to control the filter's bandwidth. In this paper the focus of the discussion and the data will be electrocorticographic (ECoG) neural signals, but the presented technique is applicable to other recordings.

Semi-Blind Noise Extraction Using Partially Known Position of the Target Source

Czech Academy of Sciences Publication Activity Database

Koldovský, Zbyněk; Málek, J.; Tichavský, Petr; Nesta, F.

2013-01-01

Roč. 21, č. 10 (2013), s. 2029-2041 ISSN 1558-7916 Grant - others:GA ČR(CZ) GAP103/11/1947 Program:GA Institutional support: RVO:67985556 Keywords : Independent component analysis * noise extraction * generalized sidelobe canceler Subject RIV: BI - Acoustics Impact factor: 2.625, year: 2013 http://library.utia.cas.cz/separaty/2013/SI/tichavsky-0396861.pdf

Combat aircraft noise

Science.gov (United States)

Sgarbozza, M.; Depitre, A.

1992-04-01

A discussion of the characteristics and the noise levels of combat aircraft and of a transport aircraft in taking off and landing are presented. Some methods of noise reduction are discussed, including the following: operational anti-noise procedures; and concepts of future engines (silent post-combustion and variable cycle). Some measurement results concerning the noise generated in flight at great speeds and low altitude will also be examined. Finally, the protection of the environment of French air bases against noise will be described and the possibilities of regulation examined.

Impulse noise estimation and removal for OFDM systems

KAUST Repository

Al-Naffouri, Tareq Y.

2014-03-01

Orthogonal Frequency Division Multiplexing (OFDM) is a modulation scheme that is widely used in wired and wireless communication systems. While OFDM is ideally suited to deal with frequency selective channels and AWGN, its performance may be dramatically impacted by the presence of impulse noise. In fact, very strong noise impulses in the time domain might result in the erasure of whole OFDM blocks of symbols at the receiver. Impulse noise can be mitigated by considering it as a sparse signal in time, and using recently developed algorithms for sparse signal reconstruction. We propose an algorithm that utilizes the guard band subcarriers for the impulse noise estimation and cancellation. Instead of relying on ℓ1 minimization as done in some popular general-purpose compressive sensing schemes, the proposed method jointly exploits the specific structure of this problem and the available a priori information for sparse signal recovery. The computational complexity of the proposed algorithm is very competitive with respect to sparse signal reconstruction schemes based on ℓ1 minimization. The proposed method is compared with respect to other state-of-the-art methods in terms of achievable rates for an OFDM system with impulse noise and AWGN. © 2014 IEEE.

Impulse noise estimation and removal for OFDM systems

KAUST Repository

Al-Naffouri, Tareq Y.; Quadeer, Ahmed Abdul; Caire, Giuseppe

2014-01-01

Orthogonal Frequency Division Multiplexing (OFDM) is a modulation scheme that is widely used in wired and wireless communication systems. While OFDM is ideally suited to deal with frequency selective channels and AWGN, its performance may be dramatically impacted by the presence of impulse noise. In fact, very strong noise impulses in the time domain might result in the erasure of whole OFDM blocks of symbols at the receiver. Impulse noise can be mitigated by considering it as a sparse signal in time, and using recently developed algorithms for sparse signal reconstruction. We propose an algorithm that utilizes the guard band subcarriers for the impulse noise estimation and cancellation. Instead of relying on ℓ1 minimization as done in some popular general-purpose compressive sensing schemes, the proposed method jointly exploits the specific structure of this problem and the available a priori information for sparse signal recovery. The computational complexity of the proposed algorithm is very competitive with respect to sparse signal reconstruction schemes based on ℓ1 minimization. The proposed method is compared with respect to other state-of-the-art methods in terms of achievable rates for an OFDM system with impulse noise and AWGN. © 2014 IEEE.

Investigation of noise in Lightwave Synthesized Frequency Sweeper seeded LIDAR anemometers from leakage through the Acousto Optic Modulators

DEFF Research Database (Denmark)

Pedersen, Anders Tegtmeier; Lindelöw, Per Jonas Petter

2009-01-01

Train (FSPT) modulated lidars the leakage will give rise to rapidly growing noise in the bins which corresponds to the signal from low radial wind velocities. It is likely that noise canceling techniques similar to those used for RIN removal has to be deployed for measurements of low wind velocities.......Lightwave Synthesized Frequency Sweepers (LSFS) have potential use as lightsources in lidar anemometers. In this paper noise due to leakage in the acousto optic modulators in an LSFS is investigated. Theoretical expressions describing the build-up of noise in the LSFS due to leakage are derived...

ELLIPTICAL WEIGHTED HOLICs FOR WEAK LENSING SHEAR MEASUREMENT. III. THE EFFECT OF RANDOM COUNT NOISE ON IMAGE MOMENTS IN WEAK LENSING ANALYSIS

International Nuclear Information System (INIS)

Okura, Yuki; Futamase, Toshifumi

2013-01-01

This is the third paper on the improvement of systematic errors in weak lensing analysis using an elliptical weight function, referred to as E-HOLICs. In previous papers, we succeeded in avoiding errors that depend on the ellipticity of the background image. In this paper, we investigate the systematic error that depends on the signal-to-noise ratio of the background image. We find that the origin of this error is the random count noise that comes from the Poisson noise of sky counts. The random count noise makes additional moments and centroid shift error, and those first-order effects are canceled in averaging, but the second-order effects are not canceled. We derive the formulae that correct this systematic error due to the random count noise in measuring the moments and ellipticity of the background image. The correction formulae obtained are expressed as combinations of complex moments of the image, and thus can correct the systematic errors caused by each object. We test their validity using a simulated image and find that the systematic error becomes less than 1% in the measured ellipticity for objects with an IMCAT significance threshold of ν ∼ 11.7.

Dispersion cancellation in a triple Laue interferometer

International Nuclear Information System (INIS)

Lemmel, Hartmut

2014-01-01

The concept of dispersion cancellation has been established in light optics to improve the resolution of interferometric measurements on dispersive media. Odd order dispersion cancellation allows to measure phase shifts without defocusing the interferometer due to wave packet displacements, while even order dispersion cancellation allows to measure time lags without losing resolution due to wave packet spreading. We report that either type of dispersion cancellation can be realized very easily in a triple Laue interferometer. Such interferometers are Mach–Zehnder interferometers based on Bragg diffraction, and are commonly used for neutrons and x-rays. Although the first x-ray interferometer was built nearly five decades ago, the feature of dispersion cancellation hasn't been recognized so far because the concept was hardly known in the neutron and x-ray community. However, it explains right away the surprising decoupling of phase shift and spatial displacement that we have discovered recently in neutron interferometry (Lemmel and Wagh 2010 Phys. Rev. A 82 033626). Furthermore, this article might inspire the light optics community to consider whether a triple Laue interferometer for laser light would be useful and feasible. We explain how dispersion cancellation works in neutron interferometry, and we describe the setup rigorously by solving the Schrödinger equation and by calculating the path integral. We point out, that the latter has to be evaluated with special care since in our setup the beam trajectory moves with respect to the crystal lattice of the interferometer. (paper)

30 CFR 280.27 - When may MMS cancel my permit?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When may MMS cancel my permit? 280.27 Section... Part Interrupted Activities § 280.27 When may MMS cancel my permit? The RD may cancel a permit at any time. (a) If we cancel your permit, the RD will advise you by certified or registered mail 30 days...

The recommendations of the noise working group

International Nuclear Information System (INIS)

Legerton, M.L.

1997-01-01

In 1993 the DTI set up a Working Group to define a framework which can be used to measure and rate the noise from wind turbines. The final report of the Noise Working Group is now available for publication. The advice on the setting of noise limits for wind farms is largely unaltered from the preliminary recommendations presented at the 17th BWEA Annual Conference [1]. This paper recaps on those recommendations and provides additional information on the measurement procedures to be used with the recommendations on noise limits. The paper describes the measurement of the existing background noise climate on which the limits are based and the procedure to be used for the measurement of turbine noise levels in the investigation of complaints. The noise limits are rated noise levels in that they can include a penalty for tones present in the noise. The level of penalty depends upon the audibility of the tone and measurement procedure for determining audibility and the associated penalty system are also described. (author)

Full-duplex wireless communications systems self-interference cancellation

CERN Document Server

Le-Ngoc, Tho

2017-01-01

This book introduces the development of self-interference (SI)-cancellation techniques for full-duplex wireless communication systems. The authors rely on estimation theory and signal processing to develop SI-cancellation algorithms by generating an estimate of the received SI and subtracting it from the received signal. The authors also cover two new SI-cancellation methods using the new concept of active signal injection (ASI) for full-duplex MIMO-OFDM systems. The ASI approach adds an appropriate cancelling signal to each transmitted signal such that the combined signals from transmit antennas attenuate the SI at the receive antennas. The authors illustrate that the SI-pre-cancelling signal does not affect the data-bearing signal. This book is for researchers and professionals working in wireless communications and engineers willing to understand the challenges of deploying full-duplex and practical solutions to implement a full-duplex system. Advanced-level students in electrical engineering and computer ...

27 CFR 479.87 - Cancellation of stamp.

Science.gov (United States)

2010-04-01

... OTHER FIREARMS Transfer Tax Application and Order for Transfer of Firearm § 479.87 Cancellation of stamp. The method of cancellation of the stamp required by this subpart as prescribed in § 479.67 shall be used. Exemptions Relating to Transfers of Firearms ...

Multimodal biometric approach for cancelable face template generation

Science.gov (United States)

Paul, Padma Polash; Gavrilova, Marina

2012-06-01

Due to the rapid growth of biometric technology, template protection becomes crucial to secure integrity of the biometric security system and prevent unauthorized access. Cancelable biometrics is emerging as one of the best solutions to secure the biometric identification and verification system. We present a novel technique for robust cancelable template generation algorithm that takes advantage of the multimodal biometric using feature level fusion. Feature level fusion of different facial features is applied to generate the cancelable template. A proposed algorithm based on the multi-fold random projection and fuzzy communication scheme is used for this purpose. In cancelable template generation, one of the main difficulties is keeping interclass variance of the feature. We have found that interclass variations of the features that are lost during multi fold random projection can be recovered using fusion of different feature subsets and projecting in a new feature domain. Applying the multimodal technique in feature level, we enhance the interclass variability hence improving the performance of the system. We have tested the system for classifier fusion for different feature subset and different cancelable template fusion. Experiments have shown that cancelable template improves the performance of the biometric system compared with the original template.

An Interactive Procedure to Preserve the Desired Edges during the Image Processing of Noise Reduction

Directory of Open Access Journals (Sweden)

Lin-Tsang Lee

2010-01-01

Full Text Available The paper propose a new procedure including four stages in order to preserve the desired edges during the image processing of noise reduction. A denoised image can be obtained from a noisy image at the first stage of the procedure. At the second stage, an edge map can be obtained by the Canny edge detector to find the edges of the object contours. Manual modification of an edge map at the third stage is optional to capture all the desired edges of the object contours. At the final stage, a new method called Edge Preserved Inhomogeneous Diffusion Equation (EPIDE is used to smooth the noisy images or the previously denoised image at the first stage for achieving the edge preservation. The Optical Character Recognition (OCR results in the experiments show that the proposed procedure has the best recognition result because of the capability of edge preservation.

CERN Library - Scientific journal cancellations

CERN Multimedia

2004-01-01

Due to the constant increase of the subscription costs of scientific journals and the current budget restrictions, the Scientific Information Policy Board has mandated the Working Group for Acquisitions (WGA) together with the Library to propose a list of titles to be cancelled at the end of 2004. As a first step, the WGA has identified the scientific journals listed at the web site below as candidates for cancellation. The choice has been guided by the personal experience of the WGA members, consultation of other expert CERN staff for highly specialized titles, and by criteria such as subscription price, impact factor, and - where available - access statistics for electronic journals. The list also accounts for the fact that many titles are subscribed to in 'packages' such that a cancellation of individual titles would not lead to any cost savings. We invite users to carefully check the list on the Library homepage (http://library.cern.ch/). If you find any title that you consider critically important for y...

Background noise levels in Europe

OpenAIRE

Gjestland, Truls

2008-01-01

- This report gives a brief overview of typical background noise levels in Europe, and suggests a procedure for the prediction of background noise levels based on population density. A proposal for the production of background noise maps for Europe is included.

Three-dimensional microarchitecture of adolescent cancellous bone

DEFF Research Database (Denmark)

Ding, Ming; Danielsen, Carl Christian; Hvid, Ivan

2012-01-01

, the adolescent cancellous bone had similar bone volume fraction (BV/TV), structure type (plate, rod or mixtures), and connectivity (3-D trabecular networks) as the adult cancellous bone. The adolescent cancellous bone had significantly lower bone surface density (bone surface per total volume of specimen...... and lateral condyle. These samples were micro-CT scanned (vivaCT 40, Scanco Medical AG, Switzerland) resulting in cubic voxel sizes of 10.5⁎10.5⁎10.5μm(3). Microarchitectural properties were calculated. The samples were then tested in compression followed by collagen and mineral determination. Interestingly...

5 CFR 837.803 - Cancellation of retirement by judicial or administrative authority.

Science.gov (United States)

2010-01-01

... Canceled Retirements § 837.803 Cancellation of retirement by judicial or administrative authority. (a... may only be canceled by the former employing agency in response to a direct and final order of a... requiring cancellation of the annuitant's separation or after the annuitant and the agency agree to cancel...

46 CFR 67.171 - Deletion; requirement and procedure.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Deletion; requirement and procedure. 67.171 Section 67...; Requirement for Exchange, Replacement, Deletion, Cancellation § 67.171 Deletion; requirement and procedure. (a... provided in § 67.161, and the vessel is subject to deletion from the roll of actively documented vessels...

Histologic Evaluation of Wound Healing After Ridge Preservation With Cortical, Cancellous, and Combined Cortico-Cancellous Freeze-Dried Bone Allograft: A Randomized Controlled Clinical Trial.

Science.gov (United States)

Demetter, Randy S; Calahan, Blaine G; Mealey, Brian L

2017-09-01

Cortical and cancellous mineralized freeze-dried bone allografts (FDBA) are available for use in alveolar ridge preservation after tooth extraction. There are currently no data regarding use of a combination 50%/50% cortico-cancellous FDBA compared with a 100% cortical or 100% cancellous FDBA in ridge preservation. The primary objective of this study is to dimensionally and histologically evaluate healing after ridge preservation in non-molar sites using 50%/50% cortico-cancellous FDBA versus 100% cortical and 100% cancellous FDBA. Sixty-six patients requiring extraction of a non-molar tooth were enrolled and randomized into three groups to receive ridge preservation with the following: 1) 100% cortical FDBA; 2) 100% cancellous FDBA; or 3) 50%/50% cortico-cancellous FDBA. After 18 to 20 weeks of healing, a biopsy was harvested, and an implant was placed. The alveolar ridge was measured pre- and postoperatively to evaluate change in ridge height and width. Percentages of vital bone, residual graft, and connective tissue (CT)/other were determined via histomorphometric analysis. Histomorphometric analysis revealed no significant differences among groups regarding percentage of vital bone or CT/other. The 100% cortical FDBA group had significantly greater residual graft material (P = 0.04). Dimensional analysis revealed no significant between-group differences in any parameter measured. To the best knowledge of the authors, this study offers the first histologic evidence demonstrating no significant difference in vital bone formation or dimensional changes among 50%/50% cortico-cancellous FDBA, 100% cortical FDBA, and 100% cancellous FDBA when used in ridge preservation of non-molar tooth sites.

Empirical properties of inter-cancellation durations in the Chinese stock market

Directory of Open Access Journals (Sweden)

Gao-Feng eGu

2014-03-01

Full Text Available Order cancellation process plays a crucial role in the dynamics of price formation in order-driven stock markets and is important in the construction and validation of computational finance models. Based on the order flow data of 23 liquid stocks traded on the Shenzhen Stock Exchange in 2003, we investigate the empirical statistical properties of inter-cancellation durations in units of events defined as the waiting times between two consecutive cancellations. The inter-cancellation durations for both buy and sell orders of all the stocks favor a $q$-exponential distribution when the maximum likelihood estimation method is adopted; In contrast, both cancelled buy orders of 9 stocks and cancelled sell orders of 4 stocks prefer Weibull distribution when the nonlinear least-square estimation is used. Applying detrended fluctuation analysis (DFA, centered detrending moving average (CDMA and multifractal detrended fluctuation analysis (MF-DFA methods, we unveil that the inter-cancellation duration time series process long memory and multifractal nature for both buy and sell cancellations of all the stocks. Our findings show that order cancellation processes exhibit long-range correlated bursty behaviors and are thus not Poissonian.

Reproduction of Realistic Background Noise for Testing Telecommunications Devices

DEFF Research Database (Denmark)

Gil Corrales, Juan David; Song, Wookeun; MacDonald, Ewen

2015-01-01

A method for reproduction of sound, based on crosstalk cancellation using inverse filters, was implemented in the context of testing telecommunications devices. The effect of the regularization parameter, number of loudspeakers, type of background noise, and a technique to attenuate audible......, the performance was equally good when using eight or four loudspeakers, and the reproduction method was shown to be robust for different program materials. The proposed technique to reduce audible artifacts increased the perceived similarity....

Dynamical cancellation of pulse-induced transients in a metallic shielded room for ultra-low-field magnetic resonance imaging

International Nuclear Information System (INIS)

Zevenhoven, Koos C. J.; Ilmoniemi, Risto J.; Dong, Hui; Clarke, John

2015-01-01

Pulse-induced transients such as eddy currents can cause problems in measurement techniques where a signal is acquired after an applied preparatory pulse. In ultra-low-field magnetic resonance imaging, performed in magnetic fields typically of the order of 100 μT, the signal-to-noise ratio is enhanced in part by prepolarizing the proton spins with a pulse of much larger magnetic field and in part by detecting the signal with a Superconducting QUantum Interference Device (SQUID). The pulse turn-off, however, can induce large eddy currents in the shielded room, producing an inhomogeneous magnetic-field transient that both seriously distorts the spin dynamics and exceeds the range of the SQUID readout. It is essential to reduce this transient substantially before image acquisition. We introduce dynamical cancellation (DynaCan), a technique in which a precisely designed current waveform is applied to a separate coil during the later part and turn off of the polarizing pulse. This waveform, which bears no resemblance to the polarizing pulse, is designed to drive the eddy currents to zero at the precise moment that the polarizing field becomes zero. We present the theory used to optimize the waveform using a detailed computational model with corrections from measured magnetic-field transients. SQUID-based measurements with DynaCan demonstrate a cancellation of 99%. Dynamical cancellation has the great advantage that, for a given system, the cancellation accuracy can be optimized in software. This technique can be applied to both metal and high-permeability alloy shielded rooms, and even to transients other than eddy currents

5 CFR 894.602 - May I cancel my enrollment at any time?

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false May I cancel my enrollment at any time... Cancellation of Coverage § 894.602 May I cancel my enrollment at any time? No. You may only cancel your enrollment during an open season. Exceptions: You may cancel your dental and/or vision enrollment if you...

Microscopic prediction of speech intelligibility in spatially distributed speech-shaped noise for normal-hearing listeners.

Science.gov (United States)

Geravanchizadeh, Masoud; Fallah, Ali

2015-12-01

A binaural and psychoacoustically motivated intelligibility model, based on a well-known monaural microscopic model is proposed. This model simulates a phoneme recognition task in the presence of spatially distributed speech-shaped noise in anechoic scenarios. In the proposed model, binaural advantage effects are considered by generating a feature vector for a dynamic-time-warping speech recognizer. This vector consists of three subvectors incorporating two monaural subvectors to model the better-ear hearing, and a binaural subvector to simulate the binaural unmasking effect. The binaural unit of the model is based on equalization-cancellation theory. This model operates blindly, which means separate recordings of speech and noise are not required for the predictions. Speech intelligibility tests were conducted with 12 normal hearing listeners by collecting speech reception thresholds (SRTs) in the presence of single and multiple sources of speech-shaped noise. The comparison of the model predictions with the measured binaural SRTs, and with the predictions of a macroscopic binaural model called extended equalization-cancellation, shows that this approach predicts the intelligibility in anechoic scenarios with good precision. The square of the correlation coefficient (r(2)) and the mean-absolute error between the model predictions and the measurements are 0.98 and 0.62 dB, respectively.

Optimal Reinsertion of Cancelled Train Lines

DEFF Research Database (Denmark)

Groth, Julie Jespersen; Clausen, Jens

2006-01-01

One recovery strategy in case of a major disruption in rail network is to cancel all trains on a specific line of the network. When the disturbance has ended, the cancelled line must be reinserted as soon as possible. In this article we present a mixed integer programming (MIP) model for calculat....... The model finds the optimal solution in an average of 0.5 CPU seconds in each test case....

An alternative method for noise analysis using pixel variance as part of quality control procedures on digital mammography systems.

NARCIS (Netherlands)

Bouwman, R.; Young, K.; Lazzari, B.; Ravaglia, V.; Broeders, M.J.M.; Engen, R. van

2009-01-01

According to the European Guidelines for quality assured breast cancer screening and diagnosis, noise analysis is one of the measurements that needs to be performed as part of quality control procedures on digital mammography systems. However, the method recommended in the European Guidelines does

Hearing loss associated with repeated MRI acquisition procedure-related acoustic noise exposure: an occupational cohort study.

Science.gov (United States)

Bongers, Suzan; Slottje, Pauline; Kromhout, Hans

2017-11-01

To study the effects of repeated exposure to MRI-related acoustic noise during image acquisition procedures (scans) on hearing. A retrospective occupational cohort study was performed among workers of an MRI manufacturing facility (n=474). Longitudinal audiometry data from the facility's medical surveillance scheme collected from 1973 to 2010 were analysed by studying the association of cumulative exposure to MRI-related acoustic noise from voluntary (multiple) MRI scans and the hearing threshold of the volunteer. Repeated acoustic noise exposure during volunteer MRI scans was found to be associated with a small exposure-dependent increased rate change of hearing threshold level (dB/year), but the association was only found related to the number of voluntary MRI scans and not to modelled cumulative noise exposure (dB*hour) based on MRI-system type. The increased rate change of hearing threshold level was found to be statistically significant for the frequencies 500, 1000, 2000, 3000 and 4000 Hz in the right ear. From our longitudinal cohort study, it appeared that exposure to noise from voluntarily MRI scans may have resulted in a slight amount of hearing loss. Mandatory use of hearing protection might have prevented more severe hearing loss. Lack of consistency in findings between the left and right ears and between the two exposure measures prohibits definitive conclusions. Further research that addresses the study's methodological limitations is warranted to corroborate our findings. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A Nonlinear Adaptive Filter for Gyro Thermal Bias Error Cancellation

Science.gov (United States)

Galante, Joseph M.; Sanner, Robert M.

2012-01-01

Deterministic errors in angular rate gyros, such as thermal biases, can have a significant impact on spacecraft attitude knowledge. In particular, thermal biases are often the dominant error source in MEMS gyros after calibration. Filters, such as J\\,fEKFs, are commonly used to mitigate the impact of gyro errors and gyro noise on spacecraft closed loop pointing accuracy, but often have difficulty in rapidly changing thermal environments and can be computationally expensive. In this report an existing nonlinear adaptive filter is used as the basis for a new nonlinear adaptive filter designed to estimate and cancel thermal bias effects. A description of the filter is presented along with an implementation suitable for discrete-time applications. A simulation analysis demonstrates the performance of the filter in the presence of noisy measurements and provides a comparison with existing techniques.

Identification and reduction of vibration and noise of a glass tempering system

International Nuclear Information System (INIS)

Ashhab, M S

2015-01-01

The vibration and noise of a glass tempering machine at a factory are studied. Experiments were conducted to identify the sources of vibration and noise. It was found that main sources for vibration and noise are two air barrels, the air pipes from the fans to the glass tempering machine and the fans location. Solutions were suggested to reduce vibration and noise from these three main sources. One of the solutions that were implemented is placing rubber dampers beneath the air barrels and pipes which almost cancelled the horizontal vibrations in the building structure and reduced the vertical vibrations to a low value most likely coming from noise. There are two types of noise, namely, radiation noise from the fans through the fans room walls and transmitted noise through the pipes caused by turbulence. A glass wool noise insulating layer was installed on the wall between the fans room and factory to reduce radiation noise through this wall. Part of the air pipe system in the factory is made of a light material which produced the highest levels of noise above 110 dBA. These air pipes were wrapped by glass wool rolls and the noise level near them was reduced to below 100 dBA which comes from other machine parts. In addition, noise levels were reduced between 2 and 15 dBA at different points in the factory. (paper)

Contributing factors of elective surgical case cancellation: a retrospective cross-sectional study at a single-site hospital.

Science.gov (United States)

Yu, Kaiye; Xie, Xiaolei; Luo, Li; Gong, Renrong

2017-09-11

Case cancellation (CC) has significant impact on the efficiency of operating room (OR) management, which can be mitigated by taking preventive measures. In this study, using the data of the West China Hospital (WCH), we identified the effect of contributing factors and recommended hospital interventions to facilitate CC prevention. We conducted a retrospective review of 11,331 elective surgical cases from January 1 to December 31, 2014. CC reasons were grouped into six categories. The methods of descriptive statistics and hypothesis test were used to identify the effect of factors. CC reasons (746) were divided into six broad categories: workup related (preoperative diagnostic assessment issues or sudden medical condition changes) (25.8%), non-specified reasons (25.8%), coordination issues (15.1%), patient related (13.0%), support system issues (11.8%), and doctor related (8.5%). The types of the most frequently performed operations are identified, as well as their CRs. The cancellation rate (CR) of males was lower than that of females (16.7% to 18.3%). A large difference in the CRs existed among doctors. The CR on Monday was significantly higher than the other four weekdays. Workup related issues, the types of procedures, the menstrual cycle of females, highly imbalanced CRs among doctors, and tendency of cancellation on Monday are the major identified factors, which account for a significant amount of preventable cancellations. It is suggested that corresponding hospital interventions can reduce CR and improve OR efficiency, including maintaining effective coordination, good communication and well-designed preoperative assessment processes, focusing on the type of procedures which are more time-consuming and complex, paying special attention to the physiology of females during surgery planning, taking measures to reduce CR of top eight doctors, and improving surgery scheduling on Monday.

A simple procedure to estimate reactivity with good noise filtering characteristics

International Nuclear Information System (INIS)

Shimazu, Yoichiro

2014-01-01

Highlights: • A new and simple on-line reactivity estimation method is proposed. • The estimator has robust noise filtering characteristics. • The noise filtering is equivalent to those of conventional reactivity meters. • The new estimator eliminates the burden of selecting optimum filter constants. • The new estimation performance is assessed without and with measurement noise. - Abstract: A new and simple on-line reactivity estimation method is proposed. The estimator has robust noise filtering characteristics without the use of complex filters. The noise filtering capability is equivalent to or better than that of a conventional estimator based on Inverse Point Kinetics (IPK). The new estimator can also eliminate the burden of selecting optimum filter time constants, such as would be required for the IPK-based estimator, or noise covariance matrices, which are needed if the extended Kalman filter (EKF) technique is used. In this paper, the new estimation method is introduced and its performance assessed without and with measurement noise

49 CFR 40.203 - What problems cause a drug test to be cancelled unless they are corrected?

Science.gov (United States)

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false What problems cause a drug test to be cancelled unless they are corrected? 40.203 Section 40.203 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Problems in Drug Tests § 40.203...

Flux Cancellation Leading to CME Filament Eruptions

Science.gov (United States)

Popescu, Roxana M.; Panesar, Navdeep K.; Sterling, Alphonse C.; Moore, Ronald L.

2016-01-01

Solar filaments are strands of relatively cool, dense plasma magnetically suspended in the lower density hotter solar corona. They trace magnetic polarity inversion lines (PILs) in the photosphere below, and are supported against gravity at heights of up to approx.100 Mm above the chromosphere by the magnetic field in and around them. This field erupts when it is rendered unstable, often by magnetic flux cancellation or emergence at or near the PIL. We have studied the evolution of photospheric magnetic flux leading to ten observed filament eruptions. Specifically, we look for gradual magnetic changes in the neighborhood of the PIL prior to and during eruption. We use Extreme Ultraviolet (EUV) images from the Atmospheric Imaging Assembly (AIA), and magnetograms from the Helioseismic and Magnetic Imager (HMI), both on board the Solar Dynamics Observatory (SDO), to study filament eruptions and their photospheric magnetic fields. We examine whether flux cancellation or/and emergence leads to filament eruptions. We find that continuous flux cancellation was present at the PIL for many hours prior to each eruption. We present two CME-producing eruptions in detail and find the following: (a) the pre-eruption filament-holding core field is highly sheared and appears in the shape of a sigmoid above the PIL; (b) at the start of the eruption the opposite arms of the sigmoid reconnect in the middle above the site of (tether-cutting) flux cancellation at the PIL; (c) the filaments first show a slow-rise, followed by a fast-rise as they erupt. We conclude that these two filament eruptions result from flux cancellation in the middle of the sheared field, and thereafter evolve in agreement with the standard model for a CME/flare filament eruption from a closed bipolar magnetic field [flux cancellation (van Ballegooijen and Martens 1989 and Moore and Roumelrotis 1992) and runaway tether-cutting (Moore et. al 2001)].

Effect of six sigma program on the number of surgeries cancellation.

Science.gov (United States)

Gheysari, Esmat; Yousefi, Hojatollah; Soleymani, Hossain; Mojdeh, Soheila

2016-01-01

Today, the rate of surgeries is increasing, but surgeries are canceled due to various reasons. Unexpected cancellation of surgeries not only results in disorder in the operating room schedule, but also causes stress for patients and their family and increases costs. We determined the number and causes of surgery cancellations and areas for improvement. This outcome evaluation of Six Sigma program was conducted on 850 cases after the implementation of the program and compared to that of 850 cases which received routine care before the program. Cases were selected through easy sampling during the study. Before the implementation, the number of cancellations was recorded daily and their reasons were investigated. Then, Six Sigma program was implemented in accordance with the reasons for each category and necessary steps were taken to prevent the cancellation of surgeries. Data were collected for 3 months using a three-section data collection form. For data analysis, distribution and relative frequency and chi-square test were used. The three categories of patient, physician, and hospital system were identified as the main causes. The highest rate of cancellation was related to ENT surgeries (74.19%). No cancellations were made in orology surgeries. The implementation of the Six Sigma program caused a significant difference in surgery cancellation (P = 0.003); 31 (3.6%) cases of cancellation were reduced to 12 (1.4%) cases. The results showed that Six Sigma program is a pre-surgery care quality improvement program. Patient education and the implementation of the 6 sigma program can be effective in reducing the rate of cancellation of operations.

Generating cancelable fingerprint templates.

Science.gov (United States)

Ratha, Nalini K; Chikkerur, Sharat; Connell, Jonathan H; Bolle, Ruud M

2007-04-01

Biometrics-based authentication systems offer obvious usability advantages over traditional password and token-based authentication schemes. However, biometrics raises several privacy concerns. A biometric is permanently associated with a user and cannot be changed. Hence, if a biometric identifier is compromised, it is lost forever and possibly for every application where the biometric is used. Moreover, if the same biometric is used in multiple applications, a user can potentially be tracked from one application to the next by cross-matching biometric databases. In this paper, we demonstrate several methods to generate multiple cancelable identifiers from fingerprint images to overcome these problems. In essence, a user can be given as many biometric identifiers as needed by issuing a new transformation "key." The identifiers can be cancelled and replaced when compromised. We empirically compare the performance of several algorithms such as Cartesian, polar, and surface folding transformations of the minutiae positions. It is demonstrated through multiple experiments that we can achieve revocability and prevent cross-matching of biometric databases. It is also shown that the transforms are noninvertible by demonstrating that it is computationally as hard to recover the original biometric identifier from a transformed version as by randomly guessing. Based on these empirical results and a theoretical analysis we conclude that feature-level cancelable biometric construction is practicable in large biometric deployments.

Measurement of drag and its cancellation

Energy Technology Data Exchange (ETDEWEB)

DeBra, D B; Conklin, J W, E-mail: johnwc@stanford.edu [Department of Aeronautics and Astronautics, Stanford University, Stanford, CA 94305-4035 (United States)

2011-05-07

The design of drag cancellation missions of the future will take advantage of the technology experience of the past. The importance of data for modeling of the atmosphere led to at least six types of measurement: (a) balloon flights, (b) missile-launched falling spheres, (c) the 'cannonball' satellites of Ken Champion with accelerometers for low-altitude drag measurement (late 1960s and early 1970s), (d) the Agena flight of LOGACS (1967), a Bell MESA accelerometer mounted on a rotating platform to spectrally shift low-frequency errors in the accelerometer, (e) a series of French low-level accelerometers (e.g. CACTUS, 1975), and (f) correction of differential accelerations for drag errors in measuring gravity gradient on a pair of satellites (GRACE, 2002). The independent invention of the drag-free satellite concept by Pugh and Lange (1964) to cancel external disturbance added implementation opportunities. Its first flight application was for ephemeris prediction improvement with the DISCOS flight (1972)-still the only extended free test mass flight. Then successful flights for reduced disturbance environment for science measurement with gyros on GP-B (2004) and for improved accuracy in geodesy and ocean studies (GOCE, 2009) each using accelerometer measurements to control the drag-canceling thrust. LISA, DECIGO, BBO and other gravity wave-measuring satellite systems will push the cancellation of drag to new levels.

Measurement of drag and its cancellation

International Nuclear Information System (INIS)

DeBra, D B; Conklin, J W

2011-01-01

The design of drag cancellation missions of the future will take advantage of the technology experience of the past. The importance of data for modeling of the atmosphere led to at least six types of measurement: (a) balloon flights, (b) missile-launched falling spheres, (c) the 'cannonball' satellites of Ken Champion with accelerometers for low-altitude drag measurement (late 1960s and early 1970s), (d) the Agena flight of LOGACS (1967), a Bell MESA accelerometer mounted on a rotating platform to spectrally shift low-frequency errors in the accelerometer, (e) a series of French low-level accelerometers (e.g. CACTUS, 1975), and (f) correction of differential accelerations for drag errors in measuring gravity gradient on a pair of satellites (GRACE, 2002). The independent invention of the drag-free satellite concept by Pugh and Lange (1964) to cancel external disturbance added implementation opportunities. Its first flight application was for ephemeris prediction improvement with the DISCOS flight (1972)-still the only extended free test mass flight. Then successful flights for reduced disturbance environment for science measurement with gyros on GP-B (2004) and for improved accuracy in geodesy and ocean studies (GOCE, 2009) each using accelerometer measurements to control the drag-canceling thrust. LISA, DECIGO, BBO and other gravity wave-measuring satellite systems will push the cancellation of drag to new levels.

A robust power spectrum split cancellation-based spectrum sensing method for cognitive radio systems

International Nuclear Information System (INIS)

Qi Pei-Han; Li Zan; Si Jiang-Bo; Gao Rui

2014-01-01

Spectrum sensing is an essential component to realize the cognitive radio, and the requirement for real-time spectrum sensing in the case of lacking prior information, fading channel, and noise uncertainty, indeed poses a major challenge to the classical spectrum sensing algorithms. Based on the stochastic properties of scalar transformation of power spectral density (PSD), a novel spectrum sensing algorithm, referred to as the power spectral density split cancellation method (PSC), is proposed in this paper. The PSC makes use of a scalar value as a test statistic, which is the ratio of each subband power to the full band power. Besides, by exploiting the asymptotic normality and independence of Fourier transform, the distribution of the ratio and the mathematical expressions for the probabilities of false alarm and detection in different channel models are derived. Further, the exact closed-form expression of decision threshold is calculated in accordance with Neyman—Pearson criterion. Analytical and simulation results show that the PSC is invulnerable to noise uncertainty, and can achive excellent detection performance without prior knowledge in additive white Gaussian noise and flat slow fading channels. In addition, the PSC benefits from a low computational cost, which can be completed in microseconds. (interdisciplinary physics and related areas of science and technology)

A robust power spectrum split cancellation-based spectrum sensing method for cognitive radio systems

Science.gov (United States)

Qi, Pei-Han; Li, Zan; Si, Jiang-Bo; Gao, Rui

2014-12-01

Spectrum sensing is an essential component to realize the cognitive radio, and the requirement for real-time spectrum sensing in the case of lacking prior information, fading channel, and noise uncertainty, indeed poses a major challenge to the classical spectrum sensing algorithms. Based on the stochastic properties of scalar transformation of power spectral density (PSD), a novel spectrum sensing algorithm, referred to as the power spectral density split cancellation method (PSC), is proposed in this paper. The PSC makes use of a scalar value as a test statistic, which is the ratio of each subband power to the full band power. Besides, by exploiting the asymptotic normality and independence of Fourier transform, the distribution of the ratio and the mathematical expressions for the probabilities of false alarm and detection in different channel models are derived. Further, the exact closed-form expression of decision threshold is calculated in accordance with Neyman—Pearson criterion. Analytical and simulation results show that the PSC is invulnerable to noise uncertainty, and can achive excellent detection performance without prior knowledge in additive white Gaussian noise and flat slow fading channels. In addition, the PSC benefits from a low computational cost, which can be completed in microseconds.

49 CFR 40.208 - What problem requires corrective action but does not result in the cancellation of a test?

Science.gov (United States)

2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false What problem requires corrective action but does not result in the cancellation of a test? 40.208 Section 40.208 Transportation Office of the Secretary of Transportation PROCEDURES FOR TRANSPORTATION WORKPLACE DRUG AND ALCOHOL TESTING PROGRAMS Problems...

A journal cancellation survey and resulting impact on interlibrary loan.

Science.gov (United States)

Nash, Jacob L; McElfresh, Karen R

2016-10-01

The research describes an extensible method of evaluating and cancelling electronic journals during a budget shortfall and evaluates implications for interlibrary loan (ILL) and user satisfaction. We calculated cost per use for cancellable electronic journal subscriptions (n=533) from the 2013 calendar year and the first half of 2014, cancelling titles with cost per use greater than $20 and less than 100 yearly uses. For remaining titles, we issued an online survey asking respondents to rank the importance of journals to their work. Finally, we gathered ILL requests and COUNTER JR2 turnaway reports for calendar year 2015. Three hundred fifty-four respondents completed the survey. Because of the level of heterogeneity of titles in the survey as well as respondents' backgrounds, most titles were reported to be never used. We developed criteria based on average response across journals to determine which to cancel. Based on this methodology, we cancelled eight journals. Examination of ILL data revealed that none of the cancelled titles were requested with any frequency. Free-text responses indicated, however, that many value free ILL as a suitable substitute for immediate full-text access to biomedical journal literature. Soliciting user feedback through an electronic survey can assist collections librarians to make electronic journal cancellation decisions during slim budgetary years. This methodology can be adapted and improved upon at other health sciences libraries.

40 CFR 205.54 - Test procedures.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Test procedures. 205.54 Section 205.54 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) NOISE ABATEMENT PROGRAMS TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Medium and Heavy Trucks § 205.54 Test procedures. The procedures described...

30 CFR 285.437 - When can my lease or grant be canceled?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When can my lease or grant be canceled? 285.437... Administration Lease Or Grant Cancellation § 285.437 When can my lease or grant be canceled? (a) The Secretary will cancel any lease or grant issued under this part upon proof that it was obtained by fraud or...

Imperfect generalized transmit beamforming with co-channel interference cancelation

KAUST Repository

Radaydeh, Redha Mahmoud Mesleh; Alouini, Mohamed-Slim

2010-01-01

of outdated statistical ordering of the interferers instantaneous powers on the effectiveness of dominant interference cancelation is investigated against the less complex adaptive arbitrary cancelation scheme. For the system models described above, new exact

An Interference Cancellation Scheme for High Reliability Based on MIMO Systems

Directory of Open Access Journals (Sweden)

Jae-Hyun Ro

2018-03-01

Full Text Available This article proposes a new interference cancellation scheme in a half-duplex based two-path relay system. In the conventional two-path relay system, inter-relay-interference (IRI which severely degrades the error performances at a destination occurs because a source and a relay transmit signals simultaneously at a specific time. The proposed scheme removes the IRI at a relay for higher signal-to-interference plus noise ratio (SINR to receive interference free signal at a destination, unlike the conventional relay system, which removes IRI at a destination. To handle the IRI, the proposed scheme uses multiple-input multiple-output (MIMO signal detection at the relays and it makes low-complexity signal processing at a destination which is a usually mobile user. At the relays, the proposed scheme uses the low-complexity QR decomposition-M algorithm (QRD-M to optimally remove the IRI. Also, for obtaining diversity gain, the proposed scheme uses cyclic delay diversity (CDD to transmit the signals at a source and the relays. In simulation results, the error performance for the proposed scheme is better when the distance between one relay and another relay is low unlike the conventional scheme because the QRD-M detects received signal in order of higher post signal-to-noise ratio (SNR.

Fermi Electronics: A Means of Correlating and Canceling Shot Noise From Solid State Devices

National Research Council Canada - National Science Library

Brown, Elliot

2004-01-01

.... Simulation results are analyzed and compared to experimental results for an InGaAs/AlAs double-barrier structure, which is the fastest resonant tunneling diode ever characterized for its noise properties...

Active cancellation of residual amplitude modulation in a frequency-modulation based Fabry-Perot interferometer.

Science.gov (United States)

Yu, Yinan; Wang, Yicheng; Pratt, Jon R

2016-03-01

Residual amplitude modulation (RAM) is one of the most common noise sources known to degrade the sensitivity of frequency modulation spectroscopy. RAM can arise as a result of the temperature dependent birefringence of the modulator crystal, which causes the orientation of the crystal's optical axis to shift with respect to the polarization of the incident light with temperature. In the fiber-based optical interferometer used on the National Institute of Standards and Technology calculable capacitor, RAM degrades the measured laser frequency stability and correlates with the environmental temperature fluctuations. We have demonstrated a simple approach that cancels out excessive RAM due to polarization mismatch between the light and the optical axis of the crystal. The approach allows us to measure the frequency noise of a heterodyne beat between two lasers individually locked to different resonant modes of a cavity with an accuracy better than 0.5 ppm, which meets the requirement to further determine the longitudinal mode number of the cavity length. Also, this approach has substantially mitigated the temperature dependency of the measurements of the cavity length and consequently the capacitance.

Infrared divergence cancellation in pure Yang-Mills theory

International Nuclear Information System (INIS)

Alvarez, A.G.

1977-01-01

Virtual and real corrections to massless external lines in pure Yang-Mills theory are considered in order to look for general features of the infrared divergence cancellation. Use of the Ward identities and sums over transverse polarization states give rise to terms formally corresponding to real ghost emission, cancelling ghost loop singularities, and to a factorisation of the hard narrow single gauge boson emission. Other virtual corrections are examined in the soft region and a graph by graph cancellation is also found. An illustrative explicit calculation of scattering of a gauge particle in an external scalar potential, including hard narrow angle emission is presented. (Auth.)

Journal cancellations in university libraries in South Africa

Directory of Open Access Journals (Sweden)

Ruth Hoskins

2010-01-01

Full Text Available This article is based on part of a survey that investigated journal cancellations in university libraries in South Africa. A study population consisting of 17 university libraries in South Africa was surveyed by means of an online questionnaire to establish the factors that influenced journal cancellations. Interpretation of the results revealed that South African university libraries, like most academic and research libraries world wide, have been adversely affected by high priced journal subscriptions and many libraries have simply cancelled subscriptions to pay for ongoing subscriptions. Recommendations are made about enhancing library budgets and access to usage statistics, supporting consortia and avoiding restrictive journal packages.

42 CFR 57.313a - Loan cancellation reimbursement.

Science.gov (United States)

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Loan cancellation reimbursement. 57.313a Section 57.313a Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS GRANTS FOR... Loans § 57.313a Loan cancellation reimbursement. In the event that insufficient funds are available to...

Adaptive noise cancellation

International Nuclear Information System (INIS)

Rizwan, N.

1999-01-01

Wavelet analysis consists of decomposing a signal or an image into a hierarchical set of approximations and details. The levels in the hierarchy correspond to those in a dyadic scale. Wavelet provide an alternative to classical Short Time Fourier Transforms for the analysis of non-stationary signals. Wavelets are defined in continuous time and discrete time. Recently Discrete Wavelet Transform (DWT) had emerged as a popular technique in Image Compression. DWT has high decorrelation and energy compaction efficiency. In this report, the effect of level of decomposition on image compression was studied and results are compared with DCT based image compression. DWT proved better in compression as there was high energy compaction and compressed image was free from blocking artifacts. (author)

The position profiles of order cancellations in an emerging stock market

International Nuclear Information System (INIS)

Gu, Gao-Feng; Ren, Fei; Zhou, Wei-Xing; Xiong, Xiong; Zhang, Wei

2013-01-01

Order submission and cancellation are two constituent actions of stock trading behaviors in order-driven markets. Order submission dynamics has been extensively studied for different markets, while order cancellation dynamics is less understood. There are two positions associated with a cancellation, that is, the price level in the limit-order book (LOB) and the position in the queue at each price level. We study the profiles of these two order cancellation positions through rebuilding the limit-order book using the order flow data of 23 liquid stocks traded on the Shenzhen Stock Exchange in the year 2003. We find that the profiles of relative price levels where cancellations occur obey a log-normal distribution. After normalizing the relative price level by removing the factor of order numbers stored at the price level, we find that the profiles exhibit a power-law scaling behavior on the right tails for both buy and sell orders. When focusing on the order cancellation positions in the queue at each price level, we find that the profiles increase rapidly in the front of the queue, and then fluctuate around a constant value till the end of the queue. These profiles are similar for different stocks. In addition, the profiles of cancellation positions can be fitted by an exponent function for both buy and sell orders. These two kinds of cancellation profiles seem universal for different stocks investigated and exhibit minor asymmetry between buy and sell orders. Our empirical findings shed new light on the order cancellation dynamics and pose constraints on the construction of order-driven stock market models. (paper)

Split SR-RLS for the Joint Initialization of the Per-Tone Equalizers and Per-Tone Echo Cancelers in DMT-Based Receivers

Directory of Open Access Journals (Sweden)

Ysebaert Geert

2004-01-01

Full Text Available In asymmetric digital subscriber lines (ADSL, the available bandwidth is divided in subcarriers or tones which are assigned to the upstream and/or downstream transmission direction. To allow efficient bidirectional communication over one twisted pair, echo cancellation is required to separate upstream and downstream channels. In addition, intersymbol interference and intercarrier interference have to be reduced by means of equalization. In this paper, a computationally efficient algorithm for adaptively initializing the per-tone equalizers (PTEQ and per-tone echo cancelers (PTEC is presented. For a given number of equalizer and echo canceler taps per-tone, it was shown that the joint PTEQ/PTEC receiver structure is able to maximize the signal-to-noise ratio (SNR on each subcarrier and hence also the achievable bit rate. The proposed initialization scheme is based on a modification of the square root recursive least squares (SR-RLS algorithm to reduce computational complexity and memory requirement compared to full SR-RLS, while keeping the convergence rate acceptably fast. Our performance analysis will show that the proposed method converges in the mean and an upper bound for the step size is given. Moreover, we will indicate how the presented initialization method can be reused in several other ADSL applications.

Noise in gravitational-wave detectors and other classical-force measurements is not influenced by test-mass quantization

International Nuclear Information System (INIS)

Braginsky, Vladimir B.; Gorodetsky, Mikhail L.; Khalili, Farid Ya.; Vyatchanin, Sergey P.; Matsko, Andrey B.; Thorne, Kip S.

2003-01-01

It is shown that photon shot noise and radiation-pressure back-action noise are the sole forms of quantum noise in interferometric gravitational wave detectors that operate near or below the standard quantum limit, if one filters the interferometer output appropriately. No additional noise arises from the test masses' initial quantum state or from reduction of the test-mass state due to measurement of the interferometer output or from the uncertainty principle associated with the test-mass state. Two features of interferometers are central to these conclusions: (i) The interferometer output [the photon number flux N(t) entering the final photodetector] commutes with itself at different times in the Heisenberg picture, [N(t),N(t ' )]=0 and thus can be regarded as classical. (ii) This number flux is linear to high accuracy in the test-mass initial position and momentum operators x o and p o , and those operators influence the measured photon flux N(t) in manners that can easily be removed by filtering. For example, in most interferometers x o and p o appear in N(t) only at the test masses' ∼1 Hz pendular swinging frequency and their influence is removed when the output data are high-pass filtered to get rid of noise below ∼10 Hz. The test-mass operators x o and p o contained in the unfiltered output N(t) make a nonzero contribution to the commutator [N(t),N(t ' )]. That contribution is precisely canceled by a nonzero commutation of the photon shot noise and radiation-pressure noise, which also are contained in N(t). This cancellation of commutators is responsible for the fact that it is possible to derive an interferometer's standard quantum limit from test-mass considerations, and independently from photon-noise considerations, and get identically the same result. These conclusions are all true for a far wider class of measurements than just gravitational-wave interferometers. To elucidate them, this paper presents a series of idealized thought experiments that

Cancellation of soft and collinear divergences in noncommutative QED

International Nuclear Information System (INIS)

Mirza, B.; Zarei, M.

2006-01-01

In this paper, we investigate the behavior of noncommutative IR divergences and will also discuss their cancellation in the physical cross sections. The commutative IR (soft) divergences existing in the nonplanar diagrams will be examined in order to prove an all-order cancellation of these divergences using the Weinberg's method. In noncommutative QED, collinear divergences due to triple photon splitting vertex, were encountered, which are shown to be canceled out by the noncommutative version of KLN theorem. This guarantees that there is no mixing between the Collinear, soft divergences and noncommutative IR divergences

Three-dimensional Microarchitecture of Adolescent Cancellous Bone

DEFF Research Database (Denmark)

Ding, Ming; Hvid, I; Overgaard, Søren

regarding three-dimensional (3-D) microarchitecture of normal adolescent cancellous bone. The objective of this study was to investigate 3-D microarchitecture of normal adolescent cancellous bone, and compared them with adult cancellous bone, thus seeking more insight into the subchondral bone adaptations...... of lateral condyle in the young adult. There were no statistical significances in the mechanical properties apart from the Young’s modulus of adolescent in anterior-posterior direction was significantly lower than the other groups. DISCUSSION: This is the first study on the 3-D microarchitecture of human......, Switzerland) resulting in cubic voxel sizes of 10*10*10 m3. Microarchitectural properties were calculated, and the mean values for either tibia, medial or lateral condyle were used in analyses. Furthermore, the samples were first tested non-destructively in compression in antero-posterior (AP) and medial...

42 CFR 57.213a - Loan cancellation reimbursement.

Science.gov (United States)

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Loan cancellation reimbursement. 57.213a Section 57... Professions Student Loans § 57.213a Loan cancellation reimbursement. (a) For loans made prior to October 22... credited to this insurance fund), and used only to reimburse the school for the institutional share of any...

Acoustical Engineering Controls and Estimated Return on Investment for DoD Selected High Noise Sources: A Roadmap for Future Noise Control in Acquisition

Science.gov (United States)

2013-04-25

20K $4.4B $8.8B Active Noise Cancellation 7 dB $30K $60K $13.2B $26.4B Tire Tread Re-design 5 dB $0.8K $2K $0.3B $0.8B Distributed TVA’s 5 dB $10K...lbs Distributed vibration absorbers $10,000 to $20,000 4 inches tall 1000 lbs Tire Tread $200-500 Minimal impact Minimal impact Hydraulic Mounts...of vibration and changing the shape and thickness of covers can reduce vibration levels and reduce radiation efficiency. Other than separating

Structural strength of cancellous specimens from bovine femur under cyclic compression

Directory of Open Access Journals (Sweden)

Kaori Endo

2016-01-01

Full Text Available The incidence of osteoporotic fractures was estimated as nine million worldwide in 2000, with particular occurrence at the proximity of joints rich in cancellous bone. Although most of these fractures spontaneously heal, some fractures progressively collapse during the early post-fracture period. Prediction of bone fragility during progressive collapse following initial fracture is clinically important. However, the mechanism of collapse, especially the gradual loss of the height in the cancellous bone region, is not clearly proved. The strength of cancellous bone after yield stress is difficult to predict since structural and mechanical strength cannot be determined a priori. The purpose of this study was to identify whether the baseline structure and volume of cancellous bone contributed to the change in cancellous bone strength under cyclic loading. A total of fifteen cubic cancellous bone specimens were obtained from two 2-year-old bovines and divided into three groups by collection regions: femoral head, neck, and proximal metaphysis. Structural indices of each 5-mm cubic specimen were determined using micro-computed tomography. Specimens were then subjected to five cycles of uniaxial compressive loading at 0.05 mm/min with initial 20 N loading, 0.3 mm displacement, and then unloading to 0.2 mm with 0.1 mm displacement for five successive cycles. Elastic modulus and yield stress of cancellous bone decreased exponentially during five loading cycles. The decrease ratio of yield stress from baseline to fifth cycle was strongly correlated with bone volume fraction (BV/TV, r = 0.96, p < 0.01 and structural model index (SMI, r = − 0.81, p < 0.01. The decrease ratio of elastic modulus from baseline to fifth cycle was also correlated with BV/TV (r = 0.80, p < 0.01 and SMI (r = − 0.78, p < 0.01. These data indicate that structural deterioration of cancellous bone is associated with bone strength after yield stress. This study suggests that

19 CFR 113.55 - Cancellation of export bonds.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 1 2010-04-01 2010-04-01 false Cancellation of export bonds. 113.55 Section 113... export bonds. (a) Manner of cancellation. A bond to assure exportation as defined in § 101.1 of this... shall be signed by a revenue officer of the foreign country to which the merchandise is exported, unless...

HUD Initiated Activity Cancellation Reports

Data.gov (United States)

Department of Housing and Urban Development — This monthly report displays all HOME activities automatically cancelled by IDIS. Effective January 1, 2011, and the beginning of every month thereafter, committed...

Handbook for industrial noise control

Science.gov (United States)

The basic principles of sound, measuring techniques, and instrumentation associated with general purpose noise control are discussed. Means for identifying and characterizing a noise problem so that subsequent work may provide the most efficient and cost effective solution are outlined. A methodology for choosing appropriate noise control materials and the proper implementation of control procedures is detailed. The most significant NASA sponsored contributions to the state of the art development of optimum noise control technologies are described including cases in which aeroacoustics and related research have shed some light on ways of reducing noise generation at its source.

Effects of noise and working memory capacity on memory processing of speech for hearing-aid users.

Science.gov (United States)

Ng, Elaine Hoi Ning; Rudner, Mary; Lunner, Thomas; Pedersen, Michael Syskind; Rönnberg, Jerker

2013-07-01

It has been shown that noise reduction algorithms can reduce the negative effects of noise on memory processing in persons with normal hearing. The objective of the present study was to investigate whether a similar effect can be obtained for persons with hearing impairment and whether such an effect is dependent on individual differences in working memory capacity. A sentence-final word identification and recall (SWIR) test was conducted in two noise backgrounds with and without noise reduction as well as in quiet. Working memory capacity was measured using a reading span (RS) test. Twenty-six experienced hearing-aid users with moderate to moderately severe sensorineural hearing loss. Noise impaired recall performance. Competing speech disrupted memory performance more than speech-shaped noise. For late list items the disruptive effect of the competing speech background was virtually cancelled out by noise reduction for persons with high working memory capacity. Noise reduction can reduce the adverse effect of noise on memory for speech for persons with good working memory capacity. We argue that the mechanism behind this is faster word identification that enhances encoding into working memory.

21 CFR 1305.19 - Cancellation and voiding of DEA Forms 222.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Cancellation and voiding of DEA Forms 222. 1305.19... I AND II CONTROLLED SUBSTANCES DEA Form 222 § 1305.19 Cancellation and voiding of DEA Forms 222. (a) A purchaser may cancel part or all of an order on a DEA Form 222 by notifying the supplier in...

Crosstalk cancellation on linearly and circularly polarized communications satellite links

Science.gov (United States)

Overstreet, W. P.; Bostian, C. W.

1979-01-01

The paper discusses the cancellation network approach for reducing crosstalk caused by depolarization on a dual-polarized communications satellite link. If the characteristics of rain depolarization are sufficiently well known, the cancellation network can be designed in a way that reduces system complexity, the most important parameter being the phase of the cross-polarized signal. Relevant theoretical calculations and experimental data are presented. The simplicity of the cancellation system proposed makes it ideal for use with small domestic or private earth terminals.

Characterization of pseudosingle bunch kick-and-cancel operational mode

Science.gov (United States)

Sun, C.; Robin, D. S.; Steier, C.; Portmann, G.

2015-12-01

Pseudosingle-bunch kick-and-cancel (PSB-KAC) is a new operational mode at the Advanced Light Source of Lawrence Berkeley National Laboratory that provides full timing and repetition rate control for single x-ray pulse users while being fully transparent to other users of synchrotron radiation light. In this operational mode, a single electron bunch is periodically displaced from a main bunch train by a fast kicker magnet with a user-on-demand repetition rate, creating a single x-ray pulse to be matched to a typical laser excitation pulse rate. This operational mode can significantly improve the signal to noise ratio of single x-ray pulse experiments and drastically reduce dose-induced sample damage rate. It greatly expands the capabilities of synchrotron light sources to carry out dynamics and time-of-flight experiments. In this paper, we carry out extensive characterizations of this PSB-KAC mode both numerically and experimentally. This includes the working principle of this mode, resonance conditions and beam stability, experimental setups, and diagnostic tools and measurements.

Characterization of pseudosingle bunch kick-and-cancel operational mode

Directory of Open Access Journals (Sweden)

C. Sun

2015-12-01

Full Text Available Pseudosingle-bunch kick-and-cancel (PSB-KAC is a new operational mode at the Advanced Light Source of Lawrence Berkeley National Laboratory that provides full timing and repetition rate control for single x-ray pulse users while being fully transparent to other users of synchrotron radiation light. In this operational mode, a single electron bunch is periodically displaced from a main bunch train by a fast kicker magnet with a user-on-demand repetition rate, creating a single x-ray pulse to be matched to a typical laser excitation pulse rate. This operational mode can significantly improve the signal to noise ratio of single x-ray pulse experiments and drastically reduce dose-induced sample damage rate. It greatly expands the capabilities of synchrotron light sources to carry out dynamics and time-of-flight experiments. In this paper, we carry out extensive characterizations of this PSB-KAC mode both numerically and experimentally. This includes the working principle of this mode, resonance conditions and beam stability, experimental setups, and diagnostic tools and measurements.

Chip-interleaved optical code division multiple access relying on a photon-counting iterative successive interference canceller for free-space optical channels.

Science.gov (United States)

Zhou, Xiaolin; Zheng, Xiaowei; Zhang, Rong; Hanzo, Lajos

2013-07-01

In this paper, we design a novel Poisson photon-counting based iterative successive interference cancellation (SIC) scheme for transmission over free-space optical (FSO) channels in the presence of both multiple access interference (MAI) as well as Gamma-Gamma atmospheric turbulence fading, shot-noise and background light. Our simulation results demonstrate that the proposed scheme exhibits a strong MAI suppression capability. Importantly, an order of magnitude of BER improvements may be achieved compared to the conventional chip-level optical code-division multiple-access (OCDMA) photon-counting detector.

50 CFR 228.13 - Determination to cancel the hearing.

Science.gov (United States)

2010-10-01

... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Determination to cancel the hearing. 228.13 Section 228.13 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND...) REGULATIONS § 228.13 Determination to cancel the hearing. (a) If the presiding officer concludes that no...

Quantum-Noise-Limited Sensitivity Enhancement of a Passive Optical Cavity by a Fast-Light Medium

Science.gov (United States)

Smith, David D.; Luckay, H. A.; Chang, Hongrok; Myneni, Krishna

2016-01-01

We demonstrate for a passive optical cavity containing a dispersive atomic medium, the increase in scale factor near the critical anomalous dispersion is not cancelled by mode broadening or attenuation, resulting in an overall increase in the predicted quantum-noise-limited sensitivity. Enhancements of over two orders of magnitude are measured in the scale factor, which translates to greater than an order-of-magnitude enhancement in the predicted quantum-noise-limited measurement precision, by temperature tuning a low-pressure vapor of non-interacting atoms in a low-finesse cavity close to the critical anomalous dispersion condition. The predicted enhancement in sensitivity is confirmed through Monte-Carlo numerical simulations.

Signal to noise ratio enhancement for Eddy Current testing of steam generator tubes in PWR's

International Nuclear Information System (INIS)

Georgel, B.

1985-01-01

Noise reduction is a compulsory task when we try to recognize and characterize flaws. The signals we deal with come from Eddy Current testings of steam generator steel tubes. We point out the need for a spectral invariant in digital spectral analysis of 2 components signals. We make clear the pros and cons of classical passband filtering and suggest the use of a new noise cancellation method first discussed by Moriwaki and Tlusty. We generalize this tricky technique and prove it is a very special case of the well-known Wiener filter. In that sense the M-T method is shown to be optimal. 6 refs

Cancellation Mechanism for Dark-Matter-Nucleon Interaction.

Science.gov (United States)

Gross, Christian; Lebedev, Oleg; Toma, Takashi

2017-11-10

We consider a simple Higgs portal dark-matter model, where the standard model is supplemented with a complex scalar whose imaginary part plays the role of weakly interacting massive particle dark matter (DM). We show that the direct DM detection cross section vanishes at the tree level and zero momentum transfer due to a cancellation by virtue of a softly broken symmetry. This cancellation is operative for any mediator masses. As a result, our electroweak-scale dark matter satisfies all of the phenomenological constraints quite naturally.

30 CFR 285.1016 - When will an Alternate Use RUE be cancelled?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When will an Alternate Use RUE be cancelled? 285.1016 Section 285.1016 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR... Rue Administration § 285.1016 When will an Alternate Use RUE be cancelled? The Secretary may cancel an...

Cancellation of differential accelerations for the LISA spacecraft

International Nuclear Information System (INIS)

Bender, Peter L

2006-01-01

The three spacecraft of the Laser Interferometer Space Antenna will form a nearly equilateral triangle with nominal side lengths of 5 million km. However, the arm lengths and the corner angles will vary by very roughly 1% over 5-10 years. Part of this variation is due to the nature of Kepler orbits around the Sun. But Sweetser (2006 Astrodynamics 2005, Advances in the Astronautical Sciences vol 123 (San Diego, CA: Univelt Inc.) pp 693-712) has shown recently that differential secular accelerations due to the Earth for the three spacecraft prevent the minimal variations from being preserved for more than 2 or 3 years. Based on Sweetser's results, it appears possible to cancel out the differential secular acceleration due to the Earth by applying forces to the two proof masses in each spacecraft. The applied acceleration is at most 2.1 x 10 -9 m s -2 . However, the directions of the required accelerations would have substantial components along the sides of the triangle, and thus the amplitudes of the applied forces would have to have very low noise, even at frequencies down to below 0.1 mHz

Multi-element determination in cancellous bone of human femoral head by PIXE

International Nuclear Information System (INIS)

Yuanxun Zhang; Yongping Zhang; Yongpeng Tong; Shijing Qiu; Xiaotao Wu; Kerong Dai

1996-01-01

Proton Induced X-ray Emission (PIXE) method is used for the determination of elemental concentrations in cancellous bone of human femoral head from five autopsies and seven patients with femoral neck broken. The specimen preparation and experimental procedure are described in detail. Using the t test, the results show that the concentrations of P, Ca, Fe, Cu, Sr in control group are higher than those in patient group, but the concentrations of S, K, Zn, Mn are not significantly different. The physiological functions of metallic elements in human bone are also discussed. (author). 19 refs., 1 fig., 4 tabs

21 CFR 1.235 - How and when do you cancel your facility's registration information?

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false How and when do you cancel your facility's... for Registration of Food Facilities § 1.235 How and when do you cancel your facility's registration information? (a) Notification of registration cancellation. A facility canceling its registration must do so...

Measured results of polarization crosstalk cancellation using LMS control. [Least Mean Square

Science.gov (United States)

Baird, C. A.; Rassweiler, G. G.

1977-01-01

This paper discusses the use of wideband decoupling networks for the cancellation of polarization crosstalk in dual-polarized communication links. Measured cancellation performance for an all-electronic IF network and an RF electro-mechanical waveguide network are presented. Each of these networks utilizes LMS-type adaptive control techniques to adjust the cancellation network.

On a possible mechanism of cosmological term cancellation

International Nuclear Information System (INIS)

Dolgov, A.D.

1982-01-01

A model is proposed in which cosmological constant is cancelled automatically because of the back reaction on it of a scalar field PHI. The cancellation takes place if two conditions are imposed on the theory, namely vanishing of mass selfinteraction of field PHI. The vacuum energy in the framework of the model considered does not dissapear completely. This leads to some modification of the standard universe expansion scheme

Time-frequency peak filtering for random noise attenuation of magnetic resonance sounding signal

Science.gov (United States)

Lin, Tingting; Zhang, Yang; Yi, Xiaofeng; Fan, Tiehu; Wan, Ling

2018-05-01

When measuring in a geomagnetic field, the method of magnetic resonance sounding (MRS) is often limited because of the notably low signal-to-noise ratio (SNR). Most current studies focus on discarding spiky noise and power-line harmonic noise cancellation. However, the effects of random noise should not be underestimated. The common method for random noise attenuation is stacking, but collecting multiple recordings merely to suppress random noise is time-consuming. Moreover, stacking is insufficient to suppress high-level random noise. Here, we propose the use of time-frequency peak filtering for random noise attenuation, which is performed after the traditional de-spiking and power-line harmonic removal method. By encoding the noisy signal with frequency modulation and estimating the instantaneous frequency using the peak of the time-frequency representation of the encoded signal, the desired MRS signal can be acquired from only one stack. The performance of the proposed method is tested on synthetic envelope signals and field data from different surveys. Good estimations of the signal parameters are obtained at different SNRs. Moreover, an attempt to use the proposed method to handle a single recording provides better results compared to 16 stacks. Our results suggest that the number of stacks can be appropriately reduced to shorten the measurement time and improve the measurement efficiency.

Geneva University - Cancelled

CERN Multimedia

Université de Genève

2010-01-01

École de physique - Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 GENEVA 4 Tel: (022) 379 62 73 - Fax: (022) 379 69 92 Monday 19 April 2010 17h00 - Stückelberg Auditorium Into the darkness: Simulating the distribution of dark matter in our Universe Prof. Volker Springel - Heidelberg Institute for Theoretical Studies   THE COLLOQUIUM IS CANCELLED. Prof. Markus Büttiker

Cancellation Effects in CSR Induced Bunch Transverse Dynamics in Bends

International Nuclear Information System (INIS)

Li, R.

2002-01-01

The partial cancellation between the effect of centrifugal space charge force on transverse bunch dynamics and the potential energy effect has been a long-standing controversial issue in the study of coherent synchrotron radiation (CSR) induced bunch dynamics in bends. In this paper, we clarify our definition of the ''centrifugal space charge force,'' and discuss the meaning of the ''cancellation effect'' and its general application. We further use simulation to demonstrate the cancellation in both steady state and transient regimes, and show the behavior of the effective transverse force

25 CFR 273.72 - Appeal from decision to cancel contract for cause.

Science.gov (United States)

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Appeal from decision to cancel contract for cause. 273.72 Section 273.72 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR INDIAN SELF-DETERMINATION AND... decision to cancel contract for cause. A contractor may appeal the decision of a Bureau official to cancel...

Poultry Plant Noise Control

Science.gov (United States)

1982-01-01

A demonstration conducted last winter at the Tip Top Poultry Plant intended to show poultry plant managers from all over the U.S. potential solutions to the problem of plant noise. Plastic covers used over sound absorbing materials need to meet cleanability requirements, high- pressure water cleaning and other harsh maintenance procedures peculiar to the poultry processing industry. For the demonstration, Fiber Flex, Inc. manufactured and donated 750 noise panels; Owens-Corning Fiberglas Corporation donated the fiberglas cores; and the cover material was purchased from Howe and Bainbridge. The Engineering Experiment Station (EES) conducted before and after noise surveys and is evaluating the effect of noise reduction on turnover and productivity in the demonstration plant. EES plans to conduct a noise abatement workshop and update a handbook to help poultry processors with noise problems. EES study and demonstration may be applicable to other food processing plants where similar sanitary constraints exist.

Analysis of Intercarrier Interference Cancellation Scheme in OFDM Systems

Directory of Open Access Journals (Sweden)

Nasir Salh Almisbah

2012-06-01

Full Text Available Abstract: Orthogonal Frequency Division Multiplexing (OFDM is an emerging multi-carrier modulation scheme, which has been adopted for several wireless standards such as IEEE 802.11a and HiperLAN2. In OFDM systems, the performance is very sensitive to subcarrier frequency errors (offset. This paper shows the analysis and derivations of intercarrier interference (ICI complex gain that used in self-cancellation scheme and its dependence on subcarrier frequency offset. Simulation shows that better improvement in performance is achieved for systems that use this cancellation scheme. Moreover, analysis and simulation show that theoretical carrier-to-interference ratio (CIR for OFDM with cancellation scheme is greater than conventional one by more than 14dB.

Interference Cancellation Using Space-Time Processing and Precoding Design

CERN Document Server

Li, Feng

2013-01-01

Interference Cancellation Using Space-Time Processing and Precoding Design introduces original design methods to achieve interference cancellation, low-complexity decoding and full diversity for a series of multi-user systems. In multi-user environments, co-channel interference will diminish the performance of wireless communications systems. In this book, we investigate how to design robust space-time codes and pre-coders to suppress the co-channel interference when multiple antennas are available.   This book offers a valuable reference work for graduate students, academic researchers and engineers who are interested in interference cancellation in wireless communications. Rigorous performance analysis and various simulation illustrations are included for each design method.   Dr. Feng Li is a scientific researcher at Cornell University.

Outage Performance in Cognitive Radio Systems with Opportunistic Interference Cancelation

DEFF Research Database (Denmark)

Di Taranto, Rocco; Popovski, Petar

2011-01-01

, respectively. The secondary receiver applies Opportunistic Interference Cancelation (OIC) and Suboptimal Opportunistic Interference Cancelation (S-OIC) thus decoding the primary signal when such an opportunity is created by the rate selected at the primary transmitter and the power received from the primary...

78 FR 48456 - Notice of Cancellation of Customs Broker Licenses

Science.gov (United States)

2013-08-08

... DEPARTMENT OF HOMELAND SECURITY U.S. Customs and Border Protection Notice of Cancellation of Customs Broker Licenses AGENCY: U.S. Customs and Border Protection, Department of Homeland Security. ACTION: Customs broker license cancellations. SUMMARY: Notice is hereby given that the customs broker...

Characteristics Analysis of Joint Acoustic Echo and Noise Suppression in Periodic Drillstring Waveguide

Directory of Open Access Journals (Sweden)

Li Cheng

2014-01-01

Full Text Available A new method of wireless data telemetry used by oil industry uses compressional acoustic waves to transmit downhole information from the bottom hole to the surface. Unfortunately, acoustic echoes and drilling vibration noises in periodic drillstring are a major issue in transmission performance. A combined acoustic echo and noise suppression method based on wave motion characteristic in drillstring is adopted to enhance an upward-going transmitted acoustic signal. The presented scheme consists of a primary acoustic echo canceller using an array of two accelerometers for dealing with the downward-going noises and a secondary acoustic insulation structure for restraining the upward-going vibration noises. Furthermore, the secondary acoustic insulation structure exhibits a banded and dispersive spectral structure because of periodic groove configuration. By using a finite-differential algorithm for the one-dimensional propagation of longitudinal waves, acoustic receiving characteristics of transmitted signals are simulated with additive Gaussian noise in a periodic pipe structure of limited length to investigate the effects on transmission performance optimization. The results reveal that the proposed scheme can achieve a much lower error bit ratio over a specified acoustic isolation frequency range with a 30–40 dB reduction in the average noise level compared to traditional single-receiver scheme.

Using Comics to Communicate Legal Contract Cancellation

Directory of Open Access Journals (Sweden)

Marietjie Botes

2017-10-01

Full Text Available This article investigates how comics can be used to adequately communicate the correct process of contract cancellation and whether comics can enhance understanding of the legal process. A survey of pre-owned vehicle buyers of various levels of education in Pretoria, South Africa found that when comics are used to communicate contract cancellation, a significant increase in the comprehension of the legal cancellation process occurs. The results may influence how contracting parties may choose to communicate complex legal issues in future, specifically to consumers with little formal education or when parties are confronted with severe language barriers, which is highly relevant in a country such as South Africa with eleven official languages and generally low levels of education. The article argues that representatives tasked with explaining contractual content to contracting parties should consider making use of comics to aid them in their communication process to ensure proper understanding and execution of terms and conditions, which in turn may lead to fewer disputes and avoid expensive litigation.

Probability Theory Plus Noise: Descriptive Estimation and Inferential Judgment.

Science.gov (United States)

Costello, Fintan; Watts, Paul

2018-01-01

We describe a computational model of two central aspects of people's probabilistic reasoning: descriptive probability estimation and inferential probability judgment. This model assumes that people's reasoning follows standard frequentist probability theory, but it is subject to random noise. This random noise has a regressive effect in descriptive probability estimation, moving probability estimates away from normative probabilities and toward the center of the probability scale. This random noise has an anti-regressive effect in inferential judgement, however. These regressive and anti-regressive effects explain various reliable and systematic biases seen in people's descriptive probability estimation and inferential probability judgment. This model predicts that these contrary effects will tend to cancel out in tasks that involve both descriptive estimation and inferential judgement, leading to unbiased responses in those tasks. We test this model by applying it to one such task, described by Gallistel et al. ). Participants' median responses in this task were unbiased, agreeing with normative probability theory over the full range of responses. Our model captures the pattern of unbiased responses in this task, while simultaneously explaining systematic biases away from normatively correct probabilities seen in other tasks. Copyright © 2018 Cognitive Science Society, Inc.

A new pathway for elective surgery to reduce cancellation rates

DEFF Research Database (Denmark)

Hovlid, Einar; Bukve, Oddbjørn; Haug, Kjell

2012-01-01

The cancellation of planned surgeries causes prolonged wait times, harm to patients, and is a waste of scarce resources. To reduce high cancellation rates in a Norwegian general hospital, the pathway for elective surgery was redesigned. The changes included earlier clinical assessment of patients...

Revenue management under customer choice behaviour with cancellations and overbooking

NARCIS (Netherlands)

Sierag, D.D.; Koole, G.M.; Mei, van der R.D.; Zwart, B.; Rest, van der J.I.

2015-01-01

In many application areas such as airlines and hotels a large number of bookings are typically cancelled. Explicitly taking into account cancellations creates an opportunity for increasing revenue. Motivated by this we propose a revenue management model based on Talluri and van Ryzin (2004) that

Noise pollution of air compressor and its noise reduction procedures by using an enclosure

Directory of Open Access Journals (Sweden)

Farhad Forouharmajd

2012-01-01

Conclusions: An overall noise reduction by 25 dB with the use of mineral wool as an extra liner on the inside of the enclosure, suggests that the effectiveness of the enclosure can be increased by using such absorber materials.

75 FR 68012 - Notice of Intention To Cancel Registrations of Certain Transfer Agents

Science.gov (United States)

2010-11-04

... SECURITIES AND EXCHANGE COMMISSION [Release No. 34-63211] Notice of Intention To Cancel... Securities Exchange Act of 1934 (``Act''),\\1\\ cancelling the registrations of the transfer agents whose names... 20549-7010 or by e- mail at [email protected] with the phrase ``Notice of Intention To Cancel...

75 FR 12561 - Delaware River and Bay Oil Spill Advisory Committee; Meeting Cancelled

Science.gov (United States)

2010-03-16

... DEPARTMENT OF HOMELAND SECURITY Coast Guard [Docket No. USCG-2008-0333] Delaware River and Bay Oil Spill Advisory Committee; Meeting Cancelled AGENCY: Coast Guard, DHS. ACTION: Notice of cancellation of...) is cancelled. FOR FURTHER INFORMATION CONTACT: Gerald Conrad, Liaison to the DFO of the DRBOSAC, (215...

Ununited fracture neck of femur treated with closed reduction and internal fixation with cancellous screw and fibular strut graft

Directory of Open Access Journals (Sweden)

Singh Daria

2006-01-01

Full Text Available Background: Ununited fracture neck of femur in young adults has been tackled in various ways. Methods: Twenty five patients of ununited fracture neck of femur in age group 21-55 years were treated by closed reduction, cancellous screw fixation and fibular strut graft and followed up for 2-6 years. Time gap between injury and operation was 6 weeks to 58 weeks. Five cases were previously fixed with various fixation devices. Results: Osseous union was achieved in 24 cases with average time of 18.16 weeks. Main complication encountered in follow-up was avascular necrosis of femoral head, others were joint stiffness and shortening. Functional end results were good to excellent in 24 cases. Conclusion: Closed reduction with internal fixation by cancellous screw and fibular strut grafting is easy and useful procedure.

Modular Engine Noise Component Prediction System (MCP) Program Users' Guide

Science.gov (United States)

Golub, Robert A. (Technical Monitor); Herkes, William H.; Reed, David H.

2004-01-01

This is a user's manual for Modular Engine Noise Component Prediction System (MCP). This computer code allows the user to predict turbofan engine noise estimates. The program is based on an empirical procedure that has evolved over many years at The Boeing Company. The data used to develop the procedure include both full-scale engine data and small-scale model data, and include testing done by Boeing, by the engine manufacturers, and by NASA. In order to generate a noise estimate, the user specifies the appropriate engine properties (including both geometry and performance parameters), the microphone locations, the atmospheric conditions, and certain data processing options. The version of the program described here allows the user to predict three components: inlet-radiated fan noise, aft-radiated fan noise, and jet noise. MCP predicts one-third octave band noise levels over the frequency range of 50 to 10,000 Hertz. It also calculates overall sound pressure levels and certain subjective noise metrics (e.g., perceived noise levels).

A general procedure to generate models for urban environmental-noise pollution using feature selection and machine learning methods.

Science.gov (United States)

Torija, Antonio J; Ruiz, Diego P

2015-02-01

The prediction of environmental noise in urban environments requires the solution of a complex and non-linear problem, since there are complex relationships among the multitude of variables involved in the characterization and modelling of environmental noise and environmental-noise magnitudes. Moreover, the inclusion of the great spatial heterogeneity characteristic of urban environments seems to be essential in order to achieve an accurate environmental-noise prediction in cities. This problem is addressed in this paper, where a procedure based on feature-selection techniques and machine-learning regression methods is proposed and applied to this environmental problem. Three machine-learning regression methods, which are considered very robust in solving non-linear problems, are used to estimate the energy-equivalent sound-pressure level descriptor (LAeq). These three methods are: (i) multilayer perceptron (MLP), (ii) sequential minimal optimisation (SMO), and (iii) Gaussian processes for regression (GPR). In addition, because of the high number of input variables involved in environmental-noise modelling and estimation in urban environments, which make LAeq prediction models quite complex and costly in terms of time and resources for application to real situations, three different techniques are used to approach feature selection or data reduction. The feature-selection techniques used are: (i) correlation-based feature-subset selection (CFS), (ii) wrapper for feature-subset selection (WFS), and the data reduction technique is principal-component analysis (PCA). The subsequent analysis leads to a proposal of different schemes, depending on the needs regarding data collection and accuracy. The use of WFS as the feature-selection technique with the implementation of SMO or GPR as regression algorithm provides the best LAeq estimation (R(2)=0.94 and mean absolute error (MAE)=1.14-1.16 dB(A)). Copyright © 2014 Elsevier B.V. All rights reserved.

Statistical and heuristic image noise extraction (SHINE): a new method for processing Poisson noise in scintigraphic images

International Nuclear Information System (INIS)

Hannequin, Pascal; Mas, Jacky

2002-01-01

Poisson noise is one of the factors degrading scintigraphic images, especially at low count level, due to the statistical nature of photon detection. We have developed an original procedure, named statistical and heuristic image noise extraction (SHINE), to reduce the Poisson noise contained in the scintigraphic images, preserving the resolution, the contrast and the texture. The SHINE procedure consists in dividing the image into 4 x 4 blocks and performing a correspondence analysis on these blocks. Each block is then reconstructed using its own significant factors which are selected using an original statistical variance test. The SHINE procedure has been validated using a line numerical phantom and a hot spots and cold spots real phantom. The reference images are the noise-free simulated images for the numerical phantom and an extremely high counts image for the real phantom. The SHINE procedure has then been applied to the Jaszczak phantom and clinical data including planar bone scintigraphy, planar Sestamibi scintigraphy and Tl-201 myocardial SPECT. The SHINE procedure reduces the mean normalized error between the noisy images and the corresponding reference images. This reduction is constant and does not change with the count level. The SNR in a SHINE processed image is close to that of the corresponding raw image with twice the number of counts. The visual results with the Jaszczak phantom SPECT have shown that SHINE preserves the contrast and the resolution of the slices well. Clinical examples have shown no visual difference between the SHINE images and the corresponding raw images obtained with twice the acquisition duration. SHINE is an entirely automatic procedure which enables halving the acquisition time or the injected dose in scintigraphic acquisitions. It can be applied to all scintigraphic images, including PET data, and to all low-count photon images

75 FR 19390 - Cydia Pomonella Granulovirus; Product Cancellation Order for a Pesticide Registration

Science.gov (United States)

2010-04-14

... the cancelled product identified in Table 1 of Unit II. in a manner inconsistent with any of the..., including any existing stocks provisions. DATES: The cancellation of the product listed in Table 1 of Unit... listed in Table 1 of this unit. Table 1.-- Cydia pomonella granulovirus Product Cancellation EPA...

Active control of multi-modal propagation of tonal noise in

DEFF Research Database (Denmark)

Laugesen, Søren

1996-01-01

The active control of tonal noise propagating in ducts at frequencies where many modes are able to propagate is considered. The final objective of the work reported is to cancel the prominent 450-500 Hz blade passing frequency of the rotary suction fans found in chimney stacks of power stations...... laboratory. The study of the full control system, which comprises thirty secondary sources and thirty-two error sensors, has revealed a number of new results, in particular with respect to the positioning of the sources and sensors along the length of the duct. Eventually, a reduction of the radiated power...

New image-processing and noise-reduction software reduces radiation dose during complex endovascular procedures.

Science.gov (United States)

Kirkwood, Melissa L; Guild, Jeffrey B; Arbique, Gary M; Tsai, Shirling; Modrall, J Gregory; Anderson, Jon A; Rectenwald, John; Timaran, Carlos

2016-11-01

A new proprietary image-processing system known as AlluraClarity, developed by Philips Healthcare (Best, The Netherlands) for radiation-based interventional procedures, claims to lower radiation dose while preserving image quality using noise-reduction algorithms. This study determined whether the surgeon and patient radiation dose during complex endovascular procedures (CEPs) is decreased after the implementation of this new operating system. Radiation dose to operators, procedure type, reference air kerma, kerma area product, and patient body mass index were recorded during CEPs on two Philips Allura FD 20 fluoroscopy systems with and without Clarity. Operator dose during CEPs was measured using optically stimulable, luminescent nanoDot (Landauer Inc, Glenwood, Ill) detectors placed outside the lead apron at the left upper chest position. nanoDots were read using a microStar ii (Landauer Inc) medical dosimetry system. For the CEPs in the Clarity group, the radiation dose to surgeons was also measured by the DoseAware (Philips Healthcare) personal dosimetry system. Side-by-side measurements of DoseAware and nanoDots allowed for cross-calibration between systems. Operator effective dose was determined using a modified Niklason algorithm. To control for patient size and case complexity, the average fluoroscopy dose rate and the dose per radiographic frame were adjusted for body mass index differences and then compared between the groups with and without Clarity by procedure. Additional factors, for example, physician practice patterns, that may have affected operator dose were inferred by comparing the ratio of the operator dose to procedural kerma area product with and without Clarity. A one-sided Wilcoxon rank sum test was used to compare groups for radiation doses, reference air kermas, and operating practices for each procedure type. The analysis included 234 CEPs; 95 performed without Clarity and 139 with Clarity. Practice patterns of operators during

Noise estimation of oil lubricated journal bearings

International Nuclear Information System (INIS)

Rho, Byoung Hoo; Kim, Kyung Woong

2003-01-01

Noise estimating procedures of oil lubricated journal bearings are presented. Nonlinear analysis of rotor-bearing system including unbalance mass of the rotor is performed in order to obtain acoustical properties of the bearing. Acoustical properties of the bearing are investigated through frequency analysis of the pressure fluctuation of the fluid film calculated from the nonlinear analysis. Noise estimating procedures presented in this paper could aid in the evaluation and understanding of acoustical properties of oil lubricated journal bearings

Design of Cancelable Palmprint Templates Based on Look Up Table

Science.gov (United States)

Qiu, Jian; Li, Hengjian; Dong, Jiwen

2018-03-01

A novel cancelable palmprint templates generation scheme is proposed in this paper. Firstly, the Gabor filter and chaotic matrix are used to extract palmprint features. It is then arranged into a row vector and divided into equal size blocks. These blocks are converted to corresponding decimals and mapped to look up tables, forming final cancelable palmprint features based on the selected check bits. Finally, collaborative representation based classification with regularized least square is used for classification. Experimental results on the Hong Kong PolyU Palmprint Database verify that the proposed cancelable templates can achieve very high performance and security levels. Meanwhile, it can also satisfy the needs of real-time applications.

Selective Adaptive Parallel Interference Cancellation for Multicarrier DS-CDMA Systems

Directory of Open Access Journals (Sweden)

Ahmed El-Sayed El-Mahdy

2013-07-01

Full Text Available In this paper, Selective Adaptive Parallel Interference Cancellation (SA-PIC technique is presented for Multicarrier Direct Sequence Code Division Multiple Access (MC DS-CDMA scheme. The motivation of using SA-PIC is that it gives high performance and at the same time, reduces the computational complexity required to perform interference cancellation. An upper bound expression of the bit error rate (BER for the SA-PIC under Rayleigh fading channel condition is derived. Moreover, the implementation complexities for SA-PIC and Adaptive Parallel Interference Cancellation (APIC are discussed and compared. The performance of SA-PIC is investigated analytically and validated via computer simulations.

20 CFR 410.233 - Cancellation of a request for withdrawal.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Cancellation of a request for withdrawal. 410.233 Section 410.233 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH AND... Entitlement; Filing of Claims and Evidence § 410.233 Cancellation of a request for withdrawal. Before or after...

30 CFR 285.534 - When may MMS cancel my bond?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When may MMS cancel my bond? 285.534 Section 285.534 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE RENEWABLE... Assurance Requirements Changes in Financial Assurance § 285.534 When may MMS cancel my bond? When your lease...

On the regge-cut cancellation in planar amplitude of the dual unitarisation scheme

International Nuclear Information System (INIS)

Kwiecinski, J.; Sakai, N.

1976-09-01

The problem of the Regge-cut cancellation in equations for planar Reggeons is considered by using the j-plane methods in treating the underlying integral equations. It is shown that the kernel should have the zero which cancels the Reggeon-loop singularity in order to eliminate the cut in the Reggeon-Reggeon scattering amplitudes besides amplitudes involving external particles. This zero (nonsense zero) implies that the finite size cluster is incompatable with the cut cancellation. Two alternatives no-double-counting conditions of the 'Reggeon-bootstrap' (the Oxford Rutherford model and the Finkelstein-Koplik model) are examined and it is found that the Regge-cut cannot be cancelled because of the finite size of the cluster. Substantial modifications of the 'Reggeon-bootstrap' model may be necessary if the Regge-cut is to be cancelled. (author)

75 FR 51053 - Propetamphos; Notice of Receipt of Requests to Voluntarily Cancel Pesticide Registrations

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2010-08-18

... of Requests to Voluntarily Cancel Pesticide Registrations AGENCY: Environmental Protection Agency... registrant, Wellmark International, to voluntarily cancel its registrations of products containing the... registrations have been canceled only if such sale, distribution, or use is consistent with the terms as...

75 FR 51048 - Notice of Receipt of Request to Voluntarily Cancel a Pesticide Registration

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2010-08-18

... Voluntarily Cancel a Pesticide Registration AGENCY: Environmental Protection Agency (EPA). ACTION: Notice... cancel a pesticide registration. DATES: Comments must be received on or before September 17, 2010... the registrant to cancel a technical grade active ingredient pesticide product registered under...

75 FR 32766 - Notice of Receipt of Requests to Voluntarily Cancel Certain Pesticide Registrations

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2010-06-09

... to Voluntarily Cancel Certain Pesticide Registrations AGENCY: Environmental Protection Agency (EPA... or Mosquitoes, LLC., to voluntarily cancel the pesticide registration for the product, Biter Fighter... registrant requested a waiver of the 180-day comment period, orders will be issued canceling this...

75 FR 70256 - Tralomethrin; Notice of Receipt of Request To Voluntarily Cancel Pesticide Registrations

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2010-11-17

... of Request To Voluntarily Cancel Pesticide Registrations AGENCY: Environmental Protection Agency (EPA... voluntarily cancel their registrations of products containing the pesticide tralomethrin. The request would... will cancel the sole technical product registration for tralomethrin. EPA intends to grant this request...

75 FR 5318 - Notice of Receipt of Requests to Voluntarily Cancel Certain Pesticide Registrations

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2010-02-02

... to Voluntarily Cancel Certain Pesticide Registrations AGENCY: Environmental Protection Agency (EPA... voluntarily cancel certain pesticide registrations. DATES: Unless a request is withdrawn by or March 4, 2010... will be issued canceling these registrations. The Agency will consider withdrawal requests postmarked...

30 CFR 250.182 - When may the Secretary cancel a lease at the exploration stage?

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2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When may the Secretary cancel a lease at the... Requirements, Lease Term Extensions, and Lease Cancellations § 250.182 When may the Secretary cancel a lease at... be modified to avoid the condition(s). The Secretary may cancel the lease if: (a) The primary lease...

76 FR 16843 - Order Cancelling Registrations of Certain Transfer Agents

Science.gov (United States)

2011-03-25

... existence or has ceased to do business as a transfer agent, the Commission shall by order cancel that... name appears in the attached Appendix either is no longer in existence or has ceased doing business as... cancel the registration of certain transfer agents whom it believed were no longer in existence or had...

Diagrammatic cancellations and the gauge dependence of QED

Energy Technology Data Exchange (ETDEWEB)

Kißler, Henry, E-mail: kissler@physik.hu-berlin.de [Department of Mathematical Sciences, University of Liverpool, L69 7ZL, Liverpool (United Kingdom); Department of Mathematics, Humboldt-Universität zu Berlin, Rudower Chaussee 25, D-12489 Berlin (Germany); Kreimer, Dirk, E-mail: kreimer@math.hu-berlin.de [Department of Mathematics, Humboldt-Universität zu Berlin, Rudower Chaussee 25, D-12489 Berlin (Germany)

2017-01-10

This letter examines diagrammatic cancellations for Quantum Electrodynamics (QED) in the general linear gauge. These cancellations combine Feynman graphs of various topologies and provide a method to reconstruct the gauge dependence of the electron propagator from the result of a particular gauge by means of a linear Dyson–Schwinger equation. We use this method in combination with dimensional regularization to demonstrate how the 3-loop ε-expansion in the Feynman gauge determines the ε-expansions for all gauge parameter dependent terms to 4 loops.

78 FR 15949 - Notice of Receipt of Request To Voluntarily Cancel Certain Pesticide Registrations

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2013-03-13

... Voluntarily Cancel Certain Pesticide Registrations AGENCY: Environmental Protection Agency (EPA). ACTION... is issuing a notice of receipt of requests by a registrant to voluntarily cancel certain pesticide... in this notice will be permitted after the registration has been canceled only if such sale...

76 FR 47579 - Notice of Receipt of Requests To Voluntarily Cancel Certain Pesticide Registrations

Science.gov (United States)

2011-08-05

... To Voluntarily Cancel Certain Pesticide Registrations AGENCY: Environmental Protection Agency (EPA... voluntarily cancel certain pesticide registrations. EPA intends to grant these requests at the close of the... will be permitted after the registrations have been cancelled only if such sale, distribution, or use...

Continuous weakly cancellative triangular subnorms: I. Their web-geometric properties

Czech Academy of Sciences Publication Activity Database

Petrík, Milan; Sarkoci, Peter

2018-01-01

Roč. 332, 1 February (2018), s. 93-110 ISSN 0165-0114 R&D Projects: GA ČR GJ15-07724Y Institutional support: RVO:67985807 Keywords : associativity * conditionally cancellative * continuous triangular subnorm * contour * level set * Reidemeister closure condition * weakly cancellative * web geometry Subject RIV: BA - General Mathematics Impact factor: 2.718, year: 2016

Surprisingly rational: probability theory plus noise explains biases in judgment.

Science.gov (United States)

Costello, Fintan; Watts, Paul

2014-07-01

The systematic biases seen in people's probability judgments are typically taken as evidence that people do not use the rules of probability theory when reasoning about probability but instead use heuristics, which sometimes yield reasonable judgments and sometimes yield systematic biases. This view has had a major impact in economics, law, medicine, and other fields; indeed, the idea that people cannot reason with probabilities has become a truism. We present a simple alternative to this view, where people reason about probability according to probability theory but are subject to random variation or noise in the reasoning process. In this account the effect of noise is canceled for some probabilistic expressions. Analyzing data from 2 experiments, we find that, for these expressions, people's probability judgments are strikingly close to those required by probability theory. For other expressions, this account produces systematic deviations in probability estimates. These deviations explain 4 reliable biases in human probabilistic reasoning (conservatism, subadditivity, conjunction, and disjunction fallacies). These results suggest that people's probability judgments embody the rules of probability theory and that biases in those judgments are due to the effects of random noise. (c) 2014 APA, all rights reserved.

Learning contrast-invariant cancellation of redundant signals in neural systems.

Directory of Open Access Journals (Sweden)

Jorge F Mejias

Full Text Available Cancellation of redundant information is a highly desirable feature of sensory systems, since it would potentially lead to a more efficient detection of novel information. However, biologically plausible mechanisms responsible for such selective cancellation, and especially those robust to realistic variations in the intensity of the redundant signals, are mostly unknown. In this work, we study, via in vivo experimental recordings and computational models, the behavior of a cerebellar-like circuit in the weakly electric fish which is known to perform cancellation of redundant stimuli. We experimentally observe contrast invariance in the cancellation of spatially and temporally redundant stimuli in such a system. Our model, which incorporates heterogeneously-delayed feedback, bursting dynamics and burst-induced STDP, is in agreement with our in vivo observations. In addition, the model gives insight on the activity of granule cells and parallel fibers involved in the feedback pathway, and provides a strong prediction on the parallel fiber potentiation time scale. Finally, our model predicts the existence of an optimal learning contrast around 15% contrast levels, which are commonly experienced by interacting fish.

A Novel Offset Cancellation Based on Parasitic-Insensitive Switched-Capacitor Sensing Circuit for the Out-of-Plane Single-Gimbaled Decoupled CMOS-MEMS Gyroscope

Science.gov (United States)

Chang, Ming-Hui; Huang, Han-Pang

2013-01-01

This paper presents a novel parasitic-insensitive switched-capacitor (PISC) sensing circuit design in order to obtain high sensitivity and ultra linearity and reduce the parasitic effect for the out-of-plane single-gimbaled decoupled CMOS-MEMS gyroscope (SGDG). According to the simulation results, the proposed PISC circuit has better sensitivity and high linearity in a wide dynamic range. Experimental results also show a better performance. In addition, the PISC circuit can use signal processing to cancel the offset and noise. Thus, this circuit is very suitable for gyroscope measurement. PMID:23493122

Stationary echo canceling in velocity estimation by time-domain cross-correlation

DEFF Research Database (Denmark)

Jensen, Jørgen Arendt

1993-01-01

The application of stationary echo canceling to ultrasonic estimation of blood velocities using time-domain cross-correlation is investigated. Expressions are derived that show the influence from the echo canceler on the signals that enter the cross-correlation estimator. It is demonstrated...

Optimization of actuator arrays for aircraft interior noise control

Science.gov (United States)

Cabell, R. H.; Lester, H. C.; Mathur, G. P.; Tran, B. N.

1993-01-01

A numerical procedure for grouping actuators in order to reduce the number of degrees of freedom in an active noise control system is evaluated using experimental data. Piezoceramic actuators for reducing aircraft interior noise are arranged into groups using a nonlinear optimization routine and clustering algorithm. An actuator group is created when two or more actuators are driven with the same control input. This procedure is suitable for active control applications where actuators are already mounted on a structure. The feasibility of this technique is demonstrated using measured data from the aft cabin of a Douglas DC-9 fuselage. The measured data include transfer functions between 34 piezoceramic actuators and 29 interior microphones and microphone responses due to the primary noise produced by external speakers. Control inputs for the grouped actuators were calculated so that a cost function, defined as a quadratic pressure term and a penalty term, was a minimum. The measured transfer functions and microphone responses are checked by comparing calculated noise reductions with measured noise reductions for four frequencies. The grouping procedure is then used to determine actuator groups that improve overall interior noise reductions by 5.3 to 15 dB, compared to the baseline experimental configuration.

Generalized synchronization induced by noise and parameter mismatching in Hindmarsh-Rose neurons

International Nuclear Information System (INIS)

Wu Ying; Xu Jianxue; He Daihai; Earn, David J.D.

2005-01-01

Synchronization of two simple neuron models has been investigated in many studies. Thresholds for complete synchronization (CS) and phase synchronization (PS) have been obtained for coupling by diffusion or noise. In addition, it has been shown that it is possible for directional diffusion to induce generalized synchronization (GS) in a pair of neuron models even if the neurons are not identical (and differ in a single parameter). We study a system of two uncoupled, nonidentical Hindmarsh-Rose (HR) neurons and show that GS can be achieved by a combination of noise and changing the value of a second parameter in one of the neurons (the second parameter mismatch cancels the first). The significance of this approach will be the greatest in situations where the parameter that is originally mismatched cannot be controlled, but a suitable controllable parameter can be identified

Anomaly cancellation and smooth non-Kahler solutions in heterotic string theory

International Nuclear Information System (INIS)

Becker, Katrin; Becker, Melanie; Fu Jixiang; Tseng, L.-S.; Yau, S.-T.

2006-01-01

We show that six-dimensional backgrounds that are T 2 bundle over a Calabi-Yau two-fold base are consistent smooth solutions of heterotic flux compactifications. We emphasize the importance of the anomaly cancellation condition which can only be satisfied if the base is K3 while a T 4 base is excluded. The conditions imposed by anomaly cancellation for the T 2 bundle structure, the dilaton field, and the holomorphic stable bundles are analyzed and the solutions determined. Applying duality, we check the consistency of the anomaly cancellation constraints with those for flux backgrounds of M-theory on eight-manifolds

Cancellation of Glauber gluon exchange in the double Drell-Yan process

International Nuclear Information System (INIS)

Diehl, Markus; Gaunt, Jonathan R.; Ostermeier, Daniel; Ploessl, Peter; Schaefer, Andreas

2015-10-01

An essential part of any factorisation proof is the demonstration that the exchange of Glauber gluons cancels for the considered observable. We show this cancellation at all orders for double Drell-Yan production (the double parton scattering process in which a pair of electroweak gauge bosons is produced) both for the integrated cross section and for the cross section differential in the transverse boson momenta. In the process of constructing this proof, we also revisit and clarify some issues regarding the Glauber cancellation argument and its relation to the rest of the factorisation proof for the single Drell-Yan process.

Measurement time and statistics for a noise thermometer with a synthetic-noise reference

Science.gov (United States)

White, D. R.; Benz, S. P.; Labenski, J. R.; Nam, S. W.; Qu, J. F.; Rogalla, H.; Tew, W. L.

2008-08-01

This paper describes methods for reducing the statistical uncertainty in measurements made by noise thermometers using digital cross-correlators and, in particular, for thermometers using pseudo-random noise for the reference signal. First, a discrete-frequency expression for the correlation bandwidth for conventional noise thermometers is derived. It is shown how an alternative frequency-domain computation can be used to eliminate the spectral response of the correlator and increase the correlation bandwidth. The corresponding expressions for the uncertainty in the measurement of pseudo-random noise in the presence of uncorrelated thermal noise are then derived. The measurement uncertainty in this case is less than that for true thermal-noise measurements. For pseudo-random sources generating a frequency comb, an additional small reduction in uncertainty is possible, but at the cost of increasing the thermometer's sensitivity to non-linearity errors. A procedure is described for allocating integration times to further reduce the total uncertainty in temperature measurements. Finally, an important systematic error arising from the calculation of ratios of statistical variables is described.

Noise annoyance caused by continuous descent approaches compared to regular descent procedures

NARCIS (Netherlands)

White, K.; Arntzen, M.; Walker, F.; Waiyaki, F.M.; Meeter, M.; Bronkhorst, A.W.

2017-01-01

During Continuous Descent Approaches (CDAs) aircraft glide towards the runway resulting in reduced noise and fuel usage. Here, we investigated whether such landings cause less noise annoyance than a regular stepwise approach. Both landing types were compared in a controlled laboratory setting with a

Cancelamento de cirurgias de catarata em um hospital público de referência Cancellation of cataract surgery in a public hospital

Directory of Open Access Journals (Sweden)

Micheli Patrícia de Fátima Magri

2012-10-01

Full Text Available OBJETIVO: Analisar a incidência e causas de cancelamento de cirurgias de catarata em um hospital público de referência. MÉTODOS: Trata-se de um estudo retrospectivo em que foram analisados o número de cancelamentos de facectomias durante o ano de 2009. Foram analisados sexo, idade, tipo de procedimento suspenso (facoemulsificação ou extração extracapsular do cristalino, tipo de anestesia, convênio (Sistema Único de Saúde ou convênio/particular e motivo de suspensão da cirurgia (causas clínicas, institucionais ou pessoais. RESULTADOS: Foram agendadas no período 2.965 cirurgias de catarata, havendo 650 cancelamentos (21,92%. Dentre as principais razões para a suspensão do procedimento destacaram-se as causas clínicas (86,90%. Os meses de inverno apresentaram os maiores índices de suspensão de cirurgias de catarata. CONCLUSÃO: A taxa de cancelamento de cirurgia de catarata em serviços públicos parece ser a mesma que há 10 anos. A principal causa de suspensão deve-se por condições clínicas (hipertensão, diabetes, falta de exames, etc..PURPOSE: To report the incidence and causes of cataract surgery cancellations in a public hospital. METHODS: This is a retrospective study, which examined the number of cancellations of cataract surgery during 2009. We analyzed the type of procedure suspended (phacoemulsification or extracapsular extraction, type of anesthesia, gender, age, covenant (public/private and the main reasons for suspension of the surgeries (clinical causes, institutional or personal. RESULTS: We analyzed 2,965 scheduled cataract surgeries, with 650 cancellations (21.92%. The main reason for the suspension of the procedure was clinical causes (86.90%. The winter months had the highest suspension rates of cataract surgery. CONCLUSION: The cancellation rate of cataract surgery in Brazilian public system seems to be the same as 10 years ago. The main cause of the suspension should be in clinical conditions

A Strategy for Understanding Noise-Induced Annoyance

Science.gov (United States)

1988-08-01

Estimation by Sequential Testing (PEST) (Taylor and Creelman , 1967) can be used to efficiently establish the indifference point for each such pair of...population on applicability of noise rating procedures". Noise Control Engineering, 4, 65-70. Taylor, M. M. & Creelman , C. D. "PEST: Efficient

Evaluation of noise pollution level based upon community exposure and response data

Science.gov (United States)

Edmiston, R. D.

1972-01-01

The results and procedures are reported from an evaluation of noise pollution level as a predictor of annoyance, based on aircraft noise exposure and community response data. The measures of noise exposure presented include composite noise rating, noise exposure forecast, noise and number index. A proposed measure as a universal noise exposure measure for noise pollution level (L sub NP) is discussed.

77 FR 19747 - Proposed Cancelation

Science.gov (United States)

2012-04-02

... DEPARTMENT OF TRANSPORTATION Office of the Secretary [Order 2012-3-7; Docket DOT-OST-2012-0022] Proposed Cancelation of the Air Taxi Authority Of VIH Cougar Helicopters, Inc. AGENCY: Department of... order finding that VIH Cougar Helicopters, Inc. is not a U.S. citizen as defined in 49 U.S.C. 40102(a...

Task-related modulation of visual neglect in cancellation tasks

OpenAIRE

Sarri, Margarita; Greenwood, Richard; Kalra, Lalit; Driver, Jon

2008-01-01

Unilateral neglect involves deficits of spatial exploration and awareness that do not always affect a fixed portion of extrapersonal space, but may vary with current stimulation and possibly with task demands. Here, we assessed any ‘top-down’, task-related influences on visual neglect, with novel experimental variants of the cancellation test. Many different versions of the cancellation test are used clinically, and can differ in the extent of neglect revealed, though the exact factors determ...

Noninvadability implies noncoexistence for a class of cancellative systems

Czech Academy of Sciences Publication Activity Database

Swart, Jan M.

2013-01-01

Roč. 18, č. 38 (2013), s. 1-12 ISSN 1083-589X R&D Projects: GA ČR GAP201/10/0752 Institutional support: RVO:67985556 Keywords : cancellative system * interface tightness * duality * coexistence * Neuhauser-Pacala model * affine voter model * rebellious voter model * balancing selection * branching * annihilation * parity preservation Subject RIV: BA - General Mathematics Impact factor: 0.627, year: 2013 http://library.utia.cas.cz/separaty/2013/SI/swart-noninvadability implies noncoexistence for a class of cancellative systems.pdf

Theoretical calculation on ICI reduction using digital coherent superposition of optical OFDM subcarrier pairs in the presence of laser phase noise.

Science.gov (United States)

Yi, Xingwen; Xu, Bo; Zhang, Jing; Lin, Yun; Qiu, Kun

2014-12-15

Digital coherent superposition (DCS) of optical OFDM subcarrier pairs with Hermitian symmetry can reduce the inter-carrier-interference (ICI) noise resulted from phase noise. In this paper, we show two different implementations of DCS-OFDM that have the same performance in the presence of laser phase noise. We complete the theoretical calculation on ICI reduction by using the model of pure Wiener phase noise. By Taylor expansion of the ICI, we show that the ICI power is cancelled to the second order by DCS. The fourth order term is further derived out and only decided by the ratio of laser linewidth to OFDM subcarrier symbol rate, which can greatly simplify the system design. Finally, we verify our theoretical calculations in simulations and use the analytical results to predict the system performance. DCS-OFDM is expected to be beneficial to certain optical fiber transmissions.

Noise levels in Damascus city

International Nuclear Information System (INIS)

Al-Oudat, M.; Maslmani, Y.

2004-01-01

Outdoor noise levels were measured at 22 sites in Damascus city. Sound level meter model NC-10 with a 20-140 dBA selectable range was used in the current investigation. At each site noise data were collected from 7 to 21 o'clock. The results showed that the noise levels were higher than WHO (World Health Organization) standard by 5-24.7 dB, 10-16 dB, 10-11 dB and 12-17 dB in residential, commercial, Commercial-industrial, and Heavy traffic streets respectively. Indoor and outdoor noise levels in some hospitals were higher than WHO standard by 15-28 dB and 19-23 dB respectively. The study showed that the authorities administration must take necessary procedures to reduce the noise levels in residential regions and in the regions surrounding the hospitals. (author)

Cancellation of Glauber gluon exchange in the double Drell-Yan process

NARCIS (Netherlands)

Diehl, M.; Gaunt, J.R.; Ostermeier, D.; Ploessl, P.; Schaefer, A.

2016-01-01

For any factorisation proof, a crucial step is a demonstration of the cancellation of so-called Glauber gluons. We summarise a recent paper in which we demonstrated this cancellation for double Drell–Yan production (the double parton scattering process in which a pair of electroweak gauge bosons is

77 FR 59190 - Halofenozide; Notice of Receipt of Requests To Voluntarily Cancel Pesticide Registrations and...

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2012-09-26

... of Requests To Voluntarily Cancel Pesticide Registrations and Terminate All Uses AGENCY... voluntarily cancel pesticide registrations of all products containing the pesticide halofenozide. The requests would cancel all technical and end-use registrations and delete all halofenozide uses. The requests...

75 FR 52340 - Fenoxycarb; Notice of Receipt of Request To Voluntarily Cancel Certain Pesticide Registrations

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2010-08-25

... of Request To Voluntarily Cancel Certain Pesticide Registrations AGENCY: Environmental Protection... registrants to voluntarily cancel registrations of products containing the pesticide fenoxycarb. The request... listed in this notice will be permitted after the registrations have been canceled only if such sale...

75 FR 28019 - Resmethrin; Notice of Receipt of Requests to Voluntarily Cancel Certain Pesticide Registrations

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2010-05-19

... of Requests to Voluntarily Cancel Certain Pesticide Registrations AGENCY: Environmental Protection... registrants to voluntarily cancel their registrations of certain products containing the pesticide resmethrin... after the registration has been cancelled only if such sale, distribution, or use is consistent with the...

46 CFR 308.524 - Application for cancellation of Open Cargo Policy, Form MA-304.

Science.gov (United States)

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false Application for cancellation of Open Cargo Policy, Form... § 308.524 Application for cancellation of Open Cargo Policy, Form MA-304. The standard form of application for cancellation of an Open Cargo Policy Form MA-304 may be obtained from the American War Risk...

Interference Cancelation Schemes for Uplink Transmission in Femtocells

DEFF Research Database (Denmark)

Thai, Chan; Popovski, Petar

2010-01-01

We present techniques that solve the near-far problems in femtocell networks. When a co-channel configuration is used, a transmission in the macrocell may cause interference to a femtocell. We introduce methods to cancel the interference caused by the macrocell to a femtocell by using the high......-rate link between the macrocell base station (BS) and the femtocell BS. In such a way, the interference from macrocell transmitters is completely cancelled when uplink transmission is used in the femtocell. Therefore, the allocation of time slots for uplink/downlink in a femtocell can be done by trying only...

75 FR 22404 - Clofencet; Notice of Receipt of Request to Voluntarily Cancel Certain Pesticide Registrations

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2010-04-28

... Request to Voluntarily Cancel Certain Pesticide Registrations AGENCY: Environmental Protection Agency (EPA... voluntarily cancel their registrations of certain products containing the pesticide clofencet. The request... cancelled only if such sale, distribution, or use is consistent with the terms as described in the final...

76 FR 36535 - Dicofol; Notice of Receipt of Request To Voluntarily Cancel Certain Pesticide Registrations

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2011-06-22

... Request To Voluntarily Cancel Certain Pesticide Registrations AGENCY: Environmental Protection Agency (EPA... registrants to voluntarily cancel their registrations of all products containing the pesticide dicofol. The... the registrations have been cancelled only if such sale, distribution, or use is consistent with the...

75 FR 24697 - Carbaryl; Notice of Receipt of Requests To Voluntarily Cancel Certain Pesticide Registrations

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2010-05-05

... Requests To Voluntarily Cancel Certain Pesticide Registrations AGENCY: Environmental Protection Agency (EPA... voluntarily cancel their registrations of certain products containing the pesticide carbaryl. The requests... of products listed in this notice will be permitted after the registration has been canceled only if...

75 FR 22402 - Methyl Parathion; Notice of Receipt of Request to Voluntarily Cancel Pesticide Registrations

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2010-04-28

... Receipt of Request to Voluntarily Cancel Pesticide Registrations AGENCY: Environmental Protection Agency... registrants to voluntarily cancel their registrations of products containing the pesticide methyl parathion... will be permitted after the registration has been cancelled only if such sale, distribution, or use is...

40 CFR Appendix I to Subparts D and E - Motorcycle Noise Emission Test Procedures [Note

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Motorcycle Noise Emission Test... (CONTINUED) NOISE ABATEMENT PROGRAMS TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Motorcycles Recall of noncomplying motorcycles; relabeling of mislabeled motorcycles. Appendix I to Subparts D and E—Motorcycle Noise...

Adaptive Feedforward Cancellation of Sinusoidal Disturbances in Superconducting RF Cavities

CERN Document Server

Kandil, T H; Hartung, W; Khalil, H; Popielarski, J; Vincent, J; York, R C

2004-01-01

A control method, known as adaptive feedforward cancellation (AFC) is applied to damp sinusoidal disturbances due to microphonics in superconducting RF (SRF) cavities. AFC provides a method for damping internal, and external sinusoidal disturbances with known frequencies. It is preferred over other schemes because it uses rudimentary information about the frequency response at the disturbance frequencies, without the necessity of knowing an analytic model (transfer function) of the system. It estimates the magnitude and phase of the sinusoidal disturbance inputs and generates a control signal to cancel their effect. AFC, along with a frequency estimation process, is shown to be very successful in the cancellation of sinusoidal signals from different sources. The results of this research may significantly reduce the power requirements and increase the stability for lightly loaded continuous-wave SRF systems.

Spatial noise in staring IR focal plane arrays

International Nuclear Information System (INIS)

Scribner, D.A.; Kruer, M.R.; Sarkady, K.; Gridley, J.C.

1988-01-01

Problems with nonuniformity correction algorithms due to nonlinear pixel response and 1/f noise have been shown previously to cause spatial noise which can be significantly greater than temporal noise. The residual spatial noise after correction cannot be reduced with time averaging. Because of spatial noise the sensitivity of staring FPA sensors is often less than predicted on the basis of the temporal noise of the individual elements. A review is given of methods for measuring and analyzing spatial noise (after nonuniformity correction) in staring infrared focal plane arrays. Automated measurement techniques are described briefly, including necessary equipment and data reduction procedures. An example of spatial noise measurements is given using a staring InSb Charge Injection Device (CID) array

75 FR 34182 - Federal Prevailing Rate Advisory Committee; Cancellation of Upcoming Meeting

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2010-06-16

... OFFICE OF PERSONNEL MANAGEMENT Federal Prevailing Rate Advisory Committee; Cancellation of... Prevailing Rate Advisory Committee is issuing this notice to cancel the June 17, 2010, public [email protected] ; or FAX: (202) 606-4264. Sheldon Friedman, Chairman, Federal Prevailing Rate...

77 FR 3326 - Cancellation of Environmental Impact Statement in Orange County, NC

Science.gov (United States)

2012-01-23

... DEPARTMENT OF TRANSPORTATION Federal Highway Administration Cancellation of Environmental Impact Statement in Orange County, NC AGENCY: Federal Highway Administration (FHWA), North Carolina Department of... US 70 Business and US 70 Bypass in Orange County, North Carolina. The project is now cancelled...

Annoyance rating of wind turbine noise

International Nuclear Information System (INIS)

Iredale, R.A.

1992-01-01

This paper proposes a simple criterion for noise limitation of wind turbines: 'The La A50 from a Wind Farm should not exceeding the L A50 of the wind generated background plus 5dB at any place of potential complaint'. This criterion is then examined and developed in the light of experience to date with turbine noise complaint and procedures. (author)

Cloaking through cancellation of diffusive wave scattering

KAUST Repository

Farhat, Mohamed

2016-08-10

A new cloaking mechanism, which makes enclosed objects invisible to diffusive photon density waves, is proposed. First, diffusive scattering from a basic core-shell geometry, which represents the cloaked structure, is studied. The conditions of scattering cancellation in a quasi-static scattering regime are derived. These allow for tailoring the diffusivity constant of the shell enclosing the object so that the fields scattered from the shell and the object cancel each other. This means that the photon flow outside the cloak behaves as if the cloaked object were not present. Diffusive light invisibility may have potential applications in hiding hot spots in infrared thermography or tissue imaging. © 2016 The Author(s) Published by the Royal Society. All rights reserved.

10 CFR 25.27 - Reopening of cases in which requests for access authorizations are canceled.

Science.gov (United States)

2010-01-01

... authorizations are canceled. 25.27 Section 25.27 Energy NUCLEAR REGULATORY COMMISSION ACCESS AUTHORIZATION Access Authorizations § 25.27 Reopening of cases in which requests for access authorizations are canceled. (a) In... cases were previously canceled, new fingerprint cards (FD-257) in duplicate and a new Security...

Suppression of enhanced physiological tremor via stochastic noise: initial observations.

Directory of Open Access Journals (Sweden)

Carlos Trenado

Full Text Available Enhanced physiological tremor is a disabling condition that arises because of unstable interactions between central tremor generators and the biomechanics of the spinal stretch reflex. Previous work has shown that peripheral input may push the tremor-related spinal and cortical systems closer to anti-phase firing, potentially leading to a reduction in tremor through phase cancellation. The aim of the present study was to investigate whether peripherally applied mechanical stochastic noise can attenuate enhanced physiological tremor and improve motor performance. Eight subjects with enhanced physiological tremor performed a visuomotor task requiring the right index finger to compensate a static force generated by a manipulandum to which Gaussian noise (3-35 Hz was applied. The finger position was displayed on-line on a monitor as a small white dot which the subjects had to maintain in the center of a larger green circle. Electromyogram (EMG from the active hand muscles and finger position were recorded. Performance was measured by the mean absolute deviation of the white dot from the zero position. Tremor was identified by the acceleration in the frequency range 7-12 Hz. Two different conditions were compared: with and without superimposed noise at optimal amplitude (determined at the beginning of the experiment. The application of optimum noise reduced tremor (accelerometric amplitude and EMG activity and improved the motor performance (reduced mean absolute deviation from zero. These data provide the first evidence of a significant reduction of enhanced physiological tremor in the human sensorimotor system due to application of external stochastic noise.

41 CFR 102-74.500 - Can Federal agencies disapprove permit applications or cancel issued permits?

Science.gov (United States)

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Can Federal agencies disapprove permit applications or cancel issued permits? 102-74.500 Section 102-74.500 Public Contracts and... cancel issued permits? Yes, Federal agencies may disapprove any permit application or cancel an issued...

Effects of white noise and holding on pain perception in newborns.

Science.gov (United States)

Karakoç, Ayse; Türker, Funda

2014-12-01

This experimental study on newborns was conducted to compare the effects of various atraumatic care procedures during an infant's crying response to pain. Included in this study were 120 newborns chosen from among healthy infants admitted to the Obstetrics Department of Çanakkale State Hospital between April 2010 and June 2010. The patients were divided into three physically homogeneous groups. Infants in group 1 were held on the mothers' laps, infants in group 2 were held on the mother's laps and listened to white noise, and infants in group 3 lay in their cribs and listened to white noise while undergoing a painful procedure. Data collection included the Neonatal Infant Pain Scale, which was used to evaluate the behavioral responses to pain during a heel prick blood draw and a newborn information sheet developed by the researcher. Changes in cardiac and respiratory rates recorded during the invasive procedure were statistically significant among the three groups (p white noise. This group was then followed by the infants who listened to white noise while being held by their mothers. The highest behavioral reaction was reported by those infants who were held by their mothers but did not listen to white noise. According to the results, white noise is an effective nonpharmacologic method to control pain, reduce crying time, and positively effect vital signs. Therefore, it is recommended that the use of white noise be practiced on newborns when they undergo painful procedures. Copyright © 2014 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

Reactor surveillance by noise analysis

International Nuclear Information System (INIS)

Ciftcioglu, Ozer

1988-01-01

A real-time noise analysis system is designed for the TRIGA reactor at Istanbul Technical University. By means of the noise techniques, reactor surveillance is performed together with failure diagnosis. The fast data processing is carried out by FFT in real-time so that malfunction or non-stationary operation of the reactor in long term can be identified by comparing the noise power spectra with the corresponding reference patterns while the decision making procedure is accomplished by the method of hypothesis testing. The system being computer based safety instrumentation involves CAMAC in conjunction with the RT-11 (PDP-11) single user dedicated environment. (author)

76 FR 12769 - Federal Prevailing Rate Advisory Committee; Cancellation of Upcoming Meeting

Science.gov (United States)

2011-03-08

... OFFICE OF PERSONNEL MANAGEMENT Federal Prevailing Rate Advisory Committee; Cancellation of... Prevailing Rate Advisory Committee is issuing this notice to cancel the March 17, 2011, public meeting..., Chairman, Federal Prevailing Rate Advisory Committee. [FR Doc. 2011-5266 Filed 3-7-11; 8:45 am] BILLING...

78 FR 20359 - Federal Prevailing Rate Advisory Committee; Cancellation of Upcoming Meeting

Science.gov (United States)

2013-04-04

... OFFICE OF PERSONNEL MANAGEMENT Federal Prevailing Rate Advisory Committee; Cancellation of... Prevailing Rate Advisory Committee is issuing this notice to cancel the April 18, 2013, public meeting... Officer, Federal Prevailing Rate Advisory Committee. [FR Doc. 2013-07875 Filed 4-3-13; 8:45 am] BILLING...

76 FR 70512 - Federal Prevailing Rate Advisory Committee; Cancellation of Upcoming Meeting

Science.gov (United States)

2011-11-14

... OFFICE OF PERSONNEL MANAGEMENT Federal Prevailing Rate Advisory Committee; Cancellation of... Prevailing Rate Advisory Committee is issuing this notice to cancel the November 17, 2011, public meeting..., Chairman, Federal Prevailing Rate Advisory Committee. [FR Doc. 2011-29274 Filed 11-10-11; 8:45 am] BILLING...

Performance analysis of an optical self-interference cancellation system with a directly modulated laser-based demonstration.

Science.gov (United States)

Yu, Yinghong; Zhang, Yunhao; Huang, Lin; Xiao, Shilin

2018-02-20

In this paper, two main performance indices of the optical self-interference cancellation (OSIC) system are theoretically analyzed: cancellation bandwidth and depth. Delay deviation is investigated to be the determining factor of cancellation bandwidth, based on which the bandwidth advantage of the OSIC system over electrical schemes is also proven theoretically. Cancellation depth in the narrowband is mostly influenced by attenuation and delay-adjusting deviation, while in the broadband case, the performance is mostly limited by frequency-dependent amplitude and phase mismatch. The cancellation performance analysis is suitable for most linear modulation-demodulation OSIC systems, including the directly modulated laser (DML)-based OSIC system verified experimentally in this paper. The cancellation model is well demonstrated by the agreement between experimental cancellation results and predicted performance. For over-the-air demonstration with the employment of antennas, broadband cancellation within 450 MHz bandwidth of 22 dB and 25 dB is achieved at 900 MHz and 2.4 GHz, respectively. In addition, orthogonal frequency division multiplexing signals are employed to show in-band full-duplex transmission with good performance by the DML-based OSIC system, with successful suppression of self-interference and recovery of the signal of interest.

Beam energy gain fluctuation in a linac caused by RF system noise

International Nuclear Information System (INIS)

Sakaki, H.; Yoshikawa, H.; Hori, T.; Yokomizo, H.

2002-01-01

In this paper, energy gain fluctuation caused by white noise in a linear accelerator is calculated. First, we formulate a computational procedure to determine the energy gain in the acceleration structure. Then, using this computational procedure, the size of the white noise of the gain is calculated. These noise sources are caused by various RF components, especially the thyratron. The calculated gain fluctuation per one RF system is ±0.054%∼±0.134%(±3σ). In general, it is difficult to control white noise. This gain fluctuation is composed only of the white noise. Therefore, this value has the same meaning as a 'Control threshold'. Thus, the control method can be evaluated based on this value

Nonlinear interaction of instability waves and vortex-pairing noise in axisymmetric subsonic jets

Science.gov (United States)

Yang, Hai-Hua; Zhou, Lin; Zhang, Xing-Chen; Wan, Zhen-Hua; Sun, De-Jun

2016-10-01

A direct simulation with selected inflow forcing is performed for an accurate description of the jet flow field and far-field noise. The effects of the Mach number and heating on the acoustic field are studied in detail. The beam patterns and acoustic intensities are both varied as the change of the Mach number and temperature. The decomposition of the source terms of the Lilley-Goldstein (L-G) equation shows that the momentum and thermodynamic components lead to distinctly different beam patterns. Significant cancellation is found between the momentum and thermodynamic components at low polar angles for the isothermal jet and large polar angles for the hot jet. The cancellation leads to the minimum values of the far-field sound. Based on linear parabolized stability equation solutions, the nonlinear interaction model for sound prediction is built in combination with the L-G equation. The dominant beam patterns and their original locations predicted by the nonlinear model are in good agreement with the direct simulation results, and the predictions of sound pressure level (SPL) by the nonlinear model are relatively reasonable.

Nonlinear interaction of instability waves and vortex-pairing noise in axisymmetric subsonic jets

Energy Technology Data Exchange (ETDEWEB)

Yang, Hai-Hua; Zhang, Xing-Chen; Wan, Zhen-Hua; Sun, De-Jun [Department of Modern Mechanics, University of Science and Technology of China, Hefei 230027 (China); Zhou, Lin, E-mail: wanzh@ustc.edu.cn [Institute of Structural Mechanics, Chinese Academy of Engineering Physics, Mianyang 623100 (China)

2016-10-15

A direct simulation with selected inflow forcing is performed for an accurate description of the jet flow field and far-field noise. The effects of the Mach number and heating on the acoustic field are studied in detail. The beam patterns and acoustic intensities are both varied as the change of the Mach number and temperature. The decomposition of the source terms of the Lilley–Goldstein (L–G) equation shows that the momentum and thermodynamic components lead to distinctly different beam patterns. Significant cancellation is found between the momentum and thermodynamic components at low polar angles for the isothermal jet and large polar angles for the hot jet. The cancellation leads to the minimum values of the far-field sound. Based on linear parabolized stability equation solutions, the nonlinear interaction model for sound prediction is built in combination with the L–G equation. The dominant beam patterns and their original locations predicted by the nonlinear model are in good agreement with the direct simulation results, and the predictions of sound pressure level (SPL) by the nonlinear model are relatively reasonable. (paper)

Investigation of signal models and methods for evaluating structures of processing telecommunication information exchange systems under acoustic noise conditions

Science.gov (United States)

Kropotov, Y. A.; Belov, A. A.; Proskuryakov, A. Y.; Kolpakov, A. A.

2018-05-01

The paper considers models and methods for estimating signals during the transmission of information messages in telecommunication systems of audio exchange. One-dimensional probability distribution functions that can be used to isolate useful signals, and acoustic noise interference are presented. An approach to the estimation of the correlation and spectral functions of the parameters of acoustic signals is proposed, based on the parametric representation of acoustic signals and the components of the noise components. The paper suggests an approach to improving the efficiency of interference cancellation and highlighting the necessary information when processing signals from telecommunications systems. In this case, the suppression of acoustic noise is based on the methods of adaptive filtering and adaptive compensation. The work also describes the models of echo signals and the structure of subscriber devices in operational command telecommunications systems.

Full-duplex MIMO system based on antenna cancellation technique

DEFF Research Database (Denmark)

Foroozanfard, Ehsan; Franek, Ondrej; Tatomirescu, Alexandru

2014-01-01

The performance of an antenna cancellation technique for a multiple-input– multiple-output (MIMO) full-duplex system that is based on null-steering beamforming and antenna polarization diversity is investigated. A practical implementation of a symmetric antenna topology comprising three dual......-polarized patch antennas operating at 2.4 GHz is described. The measurement results show an average of 60 dB self-interference cancellation over 200 MHz bandwidth. Moreover, a decoupling level of up to 22 dB is achieved for MIMO multiplexing using antenna polarization diversity. The performance evaluation...

Distortion Cancellation via Polyphase Multipath Circuits

NARCIS (Netherlands)

Mensink, E.; Klumperink, Eric A.M.; Nauta, Bram

The central question of this paper is: can we enhance the spectral purity of nonlinear circuits with the help of polyphase multipath circuits. Polyphase multipath circuits are circuits with two or more paths that exploit phase differences between the paths to cancel unwanted signals. It turns out

78 FR 41962 - Federal Prevailing Rate Advisory Committee; Cancellation of Upcoming Meeting

Science.gov (United States)

2013-07-12

... OFFICE OF PERSONNEL MANAGEMENT Federal Prevailing Rate Advisory Committee; Cancellation of... Prevailing Rate Advisory Committee is issuing this notice to cancel the July 18, 2013, public meeting... Prevailing Rate Advisory Committee. [FR Doc. 2013-16763 Filed 7-11-13; 8:45 am] BILLING CODE 6325-49-P ...

77 FR 28640 - Federal Prevailing Rate Advisory Committee; Cancellation of Upcoming Meeting

Science.gov (United States)

2012-05-15

... OFFICE OF PERSONNEL MANAGEMENT Federal Prevailing Rate Advisory Committee; Cancellation of... Prevailing Rate Advisory Committee is issuing this notice to cancel the May 24, 2012, public meeting..., Federal Prevailing Rate Advisory Committee. [FR Doc. 2012-11728 Filed 5-14-12; 8:45 am] BILLING CODE 6325...

76 FR 62422 - National Institute of Environmental Health Sciences; Cancellation of Meeting

Science.gov (United States)

2011-10-07

... DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health National Institute of Environmental Health Sciences; Cancellation of Meeting Notice is hereby given of the cancellation of the Interagency Breast Cancer and Environmental Research Coordinating Committee, October 12, 2011, 1 p.m. to 3 p.m...

Safe Harvesting of Outer Table Parietal Bone Grafts Using an Oscillating Saw and a Bone Scraper : A Refinement of Technique for Harvesting Cortical and "Cancellous"-Like Calvarial Bone

NARCIS (Netherlands)

Schortinghuis, Jurjen; Putters, Thomas F.; Raghoebar, Gerry M.

Calvarial bone is a readily available source of bone for preimplantation augmentation procedures of the alveolar process. However, the calvaria consist mostly of cortical bone, and cancellous bone of the diploic space is scarce. A bone scraper (Safescraper Twist; META, Reggio Emilia, Italy) was used

Towards a better understanding of helicopter external noise

Science.gov (United States)

Damongeot, A.; Dambra, F.; Masure, B.

The problem of helicopter external noise generation is studied taking into consideration simultaneously the multiple noise sources: rotor rotational-, rotor broadband -, and engine noise. The main data are obtained during flight tests of the rather quiet AS 332 Super Puma. The flight procedures settled by ICAO for noise regulations are used: horizontal flyover at 90 percent of the maximum speed, approach at minimum power velocity, take-off at best rate of climb. Noise source levels are assessed through narrow band analysis of ground microphone recordings, ground measurements of engine noise and theoretical means. With the perceived noise level unit used throughout the study, relative magnitude of noise sources is shown to be different from that obtained with linear noise unit. A parametric study of the influence of some helicopter parameters on external noise has shown that thickness-tapered, chord-tapered, and swept-back blade tips are good means to reduce the overall noise level in flyover and approach.

Interference Cancellation for Coexisting Wireless Data and Power Transmission in the Same Frequency

International Nuclear Information System (INIS)

Yamazaki, Keita; Sugiyama, Yusuke; Saruwatari, Shunsuke; Kawahara, Yoshihiro; Watanabe, Takashi

2014-01-01

Combining wireless transmission of data and power signals enables wireless sensor networks to drive perpetually without changing batteries. To achieve the simultaneous data and power transmission, the present paper proposes power signal interference cancellation for wireless data and power transmission at the same time in the same frequency. We evaluate the performance of the proposed power signal interference cancellation using Universal Software Radio Peripheral N200 (USRP N200) software defined radio. Evaluations show that the proposed interference cancellation is feasible to receive data while transmitting power

A mean-field approach for an intercarrier interference canceller for OFDM

International Nuclear Information System (INIS)

Sakata, A; Kabashima, Y; Peleg, Y

2012-01-01

The similarity of the mathematical description of random-field spin systems to the orthogonal frequency-division multiplexing (OFDM) scheme for wireless communication is exploited in an intercarrier interference (ICI) canceller used in the demodulation of OFDM. The translational symmetry in the Fourier domain generically concentrates the major contribution of ICI from each subcarrier in the subcarrier’s neighbourhood. This observation in conjunction with the mean-field approach leads to the development of an ICI canceller whose necessary cost of computation scales linearly with respect to the number of subcarriers. It is also shown that the dynamics of the mean-field canceller are well captured by a discrete map of a single macroscopic variable, without taking the spatial and time correlations of estimated variables into account. (paper)

Experimental Test of Entropic Noise-Disturbance Uncertainty Relations for Spin-1/2 Measurements.

Science.gov (United States)

Sulyok, Georg; Sponar, Stephan; Demirel, Bülent; Buscemi, Francesco; Hall, Michael J W; Ozawa, Masanao; Hasegawa, Yuji

2015-07-17

Information-theoretic definitions for noise and disturbance in quantum measurements were given in [Phys. Rev. Lett. 112, 050401 (2014)] and a state-independent noise-disturbance uncertainty relation was obtained. Here, we derive a tight noise-disturbance uncertainty relation for complementary qubit observables and carry out an experimental test. Successive projective measurements on the neutron's spin-1/2 system, together with a correction procedure which reduces the disturbance, are performed. Our experimental results saturate the tight noise-disturbance uncertainty relation for qubits when an optimal correction procedure is applied.

Multi moment cancellation of participant fluctuations

OpenAIRE

Begun, Viktor; Mackowiak-Pawlowska, Maja

2017-01-01

We summarize the new method for the correction of participant fluctuations in high energy nucleus-nucleus collisions. It allows to estimate a fluctuation baseline in comparison to a useful signal. In particular cases of a weak signal compared to baseline, it allows to cancel the baseline contribution from participants.

On the stochastic pendulum with Ornstein-Uhlenbeck noise

International Nuclear Information System (INIS)

Mallick, Kirone; Marcq, Philippe

2004-01-01

We study a frictionless pendulum subject to multiplicative random noise. Because of destructive interference between the angular displacement of the system and the noise term, the energy fluctuations are reduced when the noise has a non-zero correlation time. We derive the long time behaviour of the pendulum in the case of Ornstein-Uhlenbeck noise by a recursive adiabatic elimination procedure. An analytical expression for the asymptotic probability distribution function of the energy is obtained and the results agree with numerical simulations. Lastly, we compare our method with other approximation schemes

In vitro cartilage tissue engineering using cancellous bone matrix gelatin as a biodegradable scaffold

International Nuclear Information System (INIS)

Yang Bo; Yin Zhanhai; Cao Junling; Shi Zhongli; Zhang Zengtie; Liu Fuqiang; Song Hongxing; Caterson, Bruce

2010-01-01

In this study, we constructed tissue-engineered cartilage using allogeneic cancellous bone matrix gelatin (BMG) as a scaffold. Allogeneic BMG was prepared by sequential defatting, demineralization and denaturation. Isolated rabbit chondrocytes were seeded onto allogeneic cancellous BMG, and cell-BMG constructs were harvested after 1, 3 and 6 weeks for evaluation by hematoxylin and eosin staining for overall morphology, toluidine blue for extracellular matrix (ECM) proteoglycans, immunohistochemical staining for collagen type II and a transmission electron microscope for examining cellular microstructure on BMG. The prepared BMG was highly porous with mechanical strength adjustable by duration of demineralization and was easily trimmed for tissue repair. Cancellous BMG showed favorable porosity for cell habitation and metabolism material exchange with larger pore sizes (100-500 μm) than in cortical BMG (5-15 μm), allowing cell penetration. Cancellous BMG also showed good biocompatibility, which supported chondrocyte proliferation and sustained their differentiated phenotype in culture for up to 6 weeks. Rich and evenly distributed cartilage ECM proteoglycans and collagen type II were observed around chondrocytes on the surface and inside the pores throughout the cancellous BMG. Considering the large supply of banked bone allografts and relatively convenient preparation, our study suggests that allogeneic cancellous BMG is a promising scaffold for cartilage tissue engineering.

In vitro cartilage tissue engineering using cancellous bone matrix gelatin as a biodegradable scaffold

Energy Technology Data Exchange (ETDEWEB)

Yang Bo; Yin Zhanhai; Cao Junling; Shi Zhongli; Zhang Zengtie; Liu Fuqiang [College of Medicine, Xi' an Jiaotong University, Yanta West Road, No 76, Yanta District, Xi' an, Shaanxi Province 710061 (China); Song Hongxing [Department of Orthopedics, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Caterson, Bruce, E-mail: caojl@mail.xjtu.edu.c [Connective Tissue Biology Laboratories, Cardiff School of Biosciences, Cardiff University, Biomedical Building, Museum Avenue, Cardiff, CF10 3US (United Kingdom)

2010-08-01

In this study, we constructed tissue-engineered cartilage using allogeneic cancellous bone matrix gelatin (BMG) as a scaffold. Allogeneic BMG was prepared by sequential defatting, demineralization and denaturation. Isolated rabbit chondrocytes were seeded onto allogeneic cancellous BMG, and cell-BMG constructs were harvested after 1, 3 and 6 weeks for evaluation by hematoxylin and eosin staining for overall morphology, toluidine blue for extracellular matrix (ECM) proteoglycans, immunohistochemical staining for collagen type II and a transmission electron microscope for examining cellular microstructure on BMG. The prepared BMG was highly porous with mechanical strength adjustable by duration of demineralization and was easily trimmed for tissue repair. Cancellous BMG showed favorable porosity for cell habitation and metabolism material exchange with larger pore sizes (100-500 {mu}m) than in cortical BMG (5-15 {mu}m), allowing cell penetration. Cancellous BMG also showed good biocompatibility, which supported chondrocyte proliferation and sustained their differentiated phenotype in culture for up to 6 weeks. Rich and evenly distributed cartilage ECM proteoglycans and collagen type II were observed around chondrocytes on the surface and inside the pores throughout the cancellous BMG. Considering the large supply of banked bone allografts and relatively convenient preparation, our study suggests that allogeneic cancellous BMG is a promising scaffold for cartilage tissue engineering.

75 FR 57787 - Methyl Parathion; Notice of Receipt of Request to Voluntarily Cancel Certain Pesticide Registrations

Science.gov (United States)

2010-09-22

... Receipt of Request to Voluntarily Cancel Certain Pesticide Registrations AGENCY: Environmental Protection... registrant to voluntarily cancel their section 24(c) Special Local Needs (SLN) registrations of certain... after the registration has been canceled only if the sale, distribution, or use is consistent with the...

Radiographic healing and remodelling of cortical and cancellous bone grafts after rigid plate fixation

International Nuclear Information System (INIS)

Waris, P.; Karaharju, E.; Slaetis, P.; Paavolainen, P.

1980-01-01

Cortical and cancellous interposition grafts, with rigid plate fixation, in the tibiofibular bones of 130 rabbits were followed radiographically for one year. The cancellous grafts healed earlier, but by 12 weeks both graft types had been incorporated, the distal host-graft interface being the last to heal. Progressive cancellous transformation in both the graft and host bone led to an increased over-all bone diameter, a widened medullary canal and a thinned porotic wall. (Auth.)

Noise pollution mapping approach and accuracy on landscape scales.

Science.gov (United States)

Iglesias Merchan, Carlos; Diaz-Balteiro, Luis

2013-04-01

Noise mapping allows the characterization of environmental variables, such as noise pollution or soundscape, depending on the task. Strategic noise mapping (as per Directive 2002/49/EC, 2002) is a tool intended for the assessment of noise pollution at the European level every five years. These maps are based on common methods and procedures intended for human exposure assessment in the European Union that could be also be adapted for assessing environmental noise pollution in natural parks. However, given the size of such areas, there could be an alternative approach to soundscape characterization rather than using human noise exposure procedures. It is possible to optimize the size of the mapping grid used for such work by taking into account the attributes of the area to be studied and the desired outcome. This would then optimize the mapping time and the cost. This type of optimization is important in noise assessment as well as in the study of other environmental variables. This study compares 15 models, using different grid sizes, to assess the accuracy of the noise mapping of the road traffic noise at a landscape scale, with respect to noise and landscape indicators. In a study area located in the Manzanares High River Basin Regional Park in Spain, different accuracy levels (Kappa index values from 0.725 to 0.987) were obtained depending on the terrain and noise source properties. The time taken for the calculations and the noise mapping accuracy results reveal the potential for setting the map resolution in line with decision-makers' criteria and budget considerations. Copyright © 2013 Elsevier B.V. All rights reserved.

Evaluation of noise pollution level in the operating rooms of hospitals: A study in Iran.

Science.gov (United States)

Giv, Masoumeh Dorri; Sani, Karim Ghazikhanlou; Alizadeh, Majid; Valinejadi, Ali; Majdabadi, Hesamedin Askari

2017-06-01

Noise pollution in the operating rooms is one of the remaining challenges. Both patients and physicians are exposed to different sound levels during the operative cases, many of which can last for hours. This study aims to evaluate the noise pollution in the operating rooms during different surgical procedures. In this cross-sectional study, sound level in the operating rooms of Hamadan University-affiliated hospitals (totally 10) in Iran during different surgical procedures was measured using B&K sound meter. The gathered data were compared with national and international standards. Statistical analysis was performed using descriptive statistics and one-way ANOVA, t -test, and Pearson's correlation test. Noise pollution level at majority of surgical procedures is higher than national and international documented standards. The highest level of noise pollution is related to orthopedic procedures, and the lowest one related to laparoscopic and heart surgery procedures. The highest and lowest registered sound level during the operation was 93 and 55 dB, respectively. Sound level generated by equipments (69 ± 4.1 dB), trolley movement (66 ± 2.3 dB), and personnel conversations (64 ± 3.9 dB) are the main sources of noise. The noise pollution of operating rooms are higher than available standards. The procedure needs to be corrected for achieving the proper conditions.

Thirty years of progress in applications and modeling of ocean ambient noise

Science.gov (United States)

Siderius, Martin; Buckingham, Michael J.

2012-11-01

Ambient noise in the ocean is a stochastic process, which traditionally was considered to be a nuisance, since it reduced the detectability of sonar signals of interest. However, over the last thirty years, it has come to be recognized that the ambient noise itself contains useful information about the ocean and ocean processes. To extract the information, various inversion procedures have been developed, based upon which a number of practical applications of the ambient noise have evolved. Since naturally generated ambient noise is always present in the ocean, it has the advantage of being non-invasive and non-damaging to marine life, including marine mammals. In this article, a summary of the commonly encountered ambient noise models is offered, along with the associated inversion procedures, and some of the more recent applications of the ambient noise are highlighted.

77 FR 69840 - Iodomethane; Notice of Receipt of Request to Voluntarily Cancel Iodomethane Pesticide...

Science.gov (United States)

2012-11-21

... of Request to Voluntarily Cancel Iodomethane Pesticide Registrations and Amend a Registration AGENCY... voluntarily cancel the registrations of products containing the pesticide iodomethane. In addition, the... deadline identified. [[Page 69841

Retailer's inventory system in a two-level trade credit financing with selling price discount and partial order cancelations

Science.gov (United States)

Thangam, A.

2015-06-01

In today's fast marketing over the Internet or online, many retailers want to trade at the same time and change their marketing strategy to attract more customers. Some of the customers may decide to cancel their orders partially with a retailer due to various reasons such as increase in customer's waiting time, loss of customer's goodwill on retailer's business, attractive promotional schemes offered by other retailers etc. Even though there is a lag in trading and order cancelation, this paper attempts to develop the retailer's inventory model with the effect of order cancelations during advance sales period. The retailer announces a price discount program during advance sales period to promote his sales and also he offers trade credit financing during the sales periods. The retailer availing trade credit period from his supplier offers a permissible delay period to his customers. The customer who gets an item has allowed paying on or before the permissible delay period which is accounted from the buying time rather than the start period of inventory sales. This accounts for significant changes in the calculations of interest payable and interest earned by the retailer. The retailer's total cost is minimized so as to find out the optimal replenishment cycle time and price discount policies through a solution procedure. The results derived in mathematical theorems are implemented in numerical examples and sensitivity analyses on several inventory parameters are obtained.

Retailer's inventory system in a two-level trade credit financing with selling price discount and partial order cancellations

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