WorldWideScience

Sample records for non-standard noise barriers

  1. Performance of Traffic Noise Barriers with Varying Cross-Section

    Directory of Open Access Journals (Sweden)

    Sanja Grubeša

    2011-05-01

    Full Text Available The efficiency of noise barriers largely depends on their geometry. In this paper, the performance of noise barriers was simulated using the numerical Boundary Element Method (BEM. Traffic noise was particularly considered with its standardized noise spectrum adapted to human hearing. The cross-section of the barriers was varied with the goal of finding the optimum shape in comparison to classical rectangular barriers. The barrier performance was calculated at different receiver points for a fixed barrier height and source position. The magnitude of the insertion loss parameter was used to evaluate the performance change, both in one-third octave bands and as the broadband mean insertion loss value. The proposed barriers of varying cross-section were also compared with a typical T-shape barrier of the same height.

  2. Open noise barriers based on sonic crystals. Advances in noise control in transport infraestructures

    Energy Technology Data Exchange (ETDEWEB)

    Peiro Torres, M.P.; Redondo Pastor, J.; Bravo Plana-Sala, J.M.; Sanchez Perez, J.V.

    2016-07-01

    Noise control is an environmental problem of first magnitude nowadays. In this work, we present a new concept of acoustic screen designed to control the specific noise generated by transport infrastructures, based on new materials called sonic crystals. These materials are formed by arrangements of acoustic scatterers in air, and provide a new and different mechanism in the fight against noise from those of the classical screens. This mechanism is usually called multiple scattering and is due to their structuring in addition to their physical properties. Due to the separation between scatterers, these barriers are transparent to air and water allowing a reduction on their foundations. Tests carried out in a wind tunnel show a reduction of 42% in the overturning momentum compared to classical barriers. The acoustical performance of these barriers is shown in this work, explaining the new characteristics provided in the control of noise. Finally, an example of these barriers is presented and classified according to acoustic standardization tests. The acoustic barrier reported in this work provides a high technological solution in the field of noise control. (Author)

  3. Highway renewable energy : photovoltaic noise barriers

    Science.gov (United States)

    2017-07-01

    Highway photovoltaic noise barriers (PVNBs) represent the combination of noise barrier systems and photovoltaic systems in order to mitigate traffic noise while simultaneously producing renewable energy. First deployed in Switzerland in 1989, PVNBs a...

  4. Hempcrete Noise Barrier Wall for Highway Noise Insulation : Research & Construction

    OpenAIRE

    KC, Prabesh

    2016-01-01

    The purpose of this thesis was to study the possibility of Hempcrete or hemp-lime composite noise barrier walls in the highways and to construct the walls for the acoustic test according to the European Union Standards EN ISO 717-1 and ISO 10140-2 for air-borne sound insulation. The thesis was commissioned by the company Hemprefine Oy, and all the standard tests were performed in the HAMK-Ruukki Sheet Metal Centre in Hämeenlinna and the VTT Technical Research Centre of Finland Ltd in Espoo. ...

  5. SOME OBSERVATIONS ON THE DESIGN OF NOISE BARRIERS

    OpenAIRE

    Arkadiusz BOCZKOWSKI

    2013-01-01

    The issue connected with effectiveness of noise barriers has been the subject of numerous considerations among acousticians. On the one hand, noise barriers are still the most popular and the most frequently used protection against traffic noise, on the other hand, however, the excessive number of noise barriers and the results of research focusing on effectiveness of the existing barriers make us reflect whether it is reasonable to use them. Very often low effectiveness of noise barriers is ...

  6. SOME OBSERVATIONS ON THE DESIGN OF NOISE BARRIERS

    Directory of Open Access Journals (Sweden)

    Arkadiusz BOCZKOWSKI

    2013-04-01

    Full Text Available The issue connected with effectiveness of noise barriers has been the subject of numerous considerations among acousticians. On the one hand, noise barriers are still the most popular and the most frequently used protection against traffic noise, on the other hand, however, the excessive number of noise barriers and the results of research focusing on effectiveness of the existing barriers make us reflect whether it is reasonable to use them. Very often low effectiveness of noise barriers is related to a badly conducted designing process. This article presents the basic mistakes made by noise barriers’ designers and the consequences thereof. Next, the paper describes the appropriate approach to the process of the noise barriers’ design which consists in the use of computer methods and conducting of a detailed analysis of the acoustic field’s distribution both behind the barrier and on the facades of the acoustically protected buildings.

  7. New solution for transport and industrial noise protection through reflective noise barriers

    Directory of Open Access Journals (Sweden)

    Kralov Ivan

    2017-01-01

    Full Text Available A new solution for protection of transportation and industrial noise through reflective noise barriers is proposed and investigated in this study. The new solution combines the advantages of the known barriers and has its own advantages in addition. The preliminary results show a very good level of noise reduction for this type of barriers.

  8. Optimal Height Calculation and Modelling of Noise Barrier

    Directory of Open Access Journals (Sweden)

    Raimondas Grubliauskas

    2011-04-01

    Full Text Available Transport is one of the main sources of noise having a particularly strong negative impact on the environment. In the city, one of the best methods to reduce the spread of noise in residential areas is a noise barrier. The article presents noise reduction barrier adaptation with empirical formulas calculating and modelling noise distribution. The simulation of noise dispersion has been performed applying the CadnaA program that allows modelling the noise levels of various developments under changing conditions. Calculation and simulation is obtained by assessing the level of noise reduction using the same variables. The investigation results are presented as noise distribution isolines. The selection of a different height of noise barriers are the results calculated at the heights of 1, 4 and 15 meters. The level of noise reduction at the maximum overlap of data, calculation and simulation has reached about 10%.Article in Lithuanian

  9. QUIESST, toward a better knowledge and understanding of how efficient noise barriers could actually be: noise in the built environment

    NARCIS (Netherlands)

    Clairbois, J.-P.; Roo, F. de; Garai, M.; Conter, M.; Defrance, J.; Oltean-Dumbrava, C.; Fusco, I.

    2010-01-01

    Since the early 80's, one models noise propagation, in the early 90's one started to standardize how to measure the intrinsic characteristics of manufactured noise barriers: in 1997, the EU funded ADRIENNE research ([1] and [2]) was a first step, but many problems still remained. Since years, all

  10. Photovoltaic noise barriers; Stille um die Laermschutzwand

    Energy Technology Data Exchange (ETDEWEB)

    Roepcke, I.

    2007-11-30

    Photovoltaic noise barriers are uncommon. There were some demonstration project, but interest died down - in spite of the fact that the EEG specifies the same level of reimbursement for PV noise barriers as for PlV roofs. Recently, efforts have been made to revive the market. (orig.)

  11. Simulating complex noise barrier reflections

    NARCIS (Netherlands)

    Eerden, F.J.M. van der; Lutgendorf, D.; Roo, F. de

    2011-01-01

    Within the EU FP7 QUIESST project, QUIeting the Environment for a Sustainable Surface Transport, a test method is being developed for the reflectivity of noise barriers. The method needs to account for a complex shape of barriers and the use of various types of absorbing materials. The performance

  12. Non-Markovian noise

    International Nuclear Information System (INIS)

    Fulinski, A.

    1994-01-01

    The properties of non-Markovian noises with exponentially correlated memory are discussed. Considered are dichotomic noise, white shot noise, Gaussian white noise, and Gaussian colored noise. The stationary correlation functions of the non-Markovian versions of these noises are given by linear combinations of two or three exponential functions (colored noises) or of the δ function and exponential function (white noises). The non-Markovian white noises are well defined only when the kernel of the non-Markovian master equation contains a nonzero admixture of a Markovian term. Approximate equations governing the probability densities for processes driven by such non-Markovian noises are derived, including non-Markovian versions of the Fokker-Planck equation and the telegrapher's equation. As an example, it is shown how the non-Markovian nature changes the behavior of the driven linear process

  13. The study for installing noise barrier on highway route no.9

    Directory of Open Access Journals (Sweden)

    Jiradecha Chaddanai

    2018-01-01

    Full Text Available Highway Route No. 9 is a Bangkok bypass motorway that aims to alleviate traffic congestion in greater Bangkok areas. Presently, it is found a rapid expansion of new communities residing along both side of Highway No. 9. To lessen the noise level, Department of Highways installed the noise barrier on the sensitive locations. However, people from communities living on both sides of highway still demand some additional noise pollution improvement. To improve the efficiency of using noise barriers and to promote environmental and social quality for the people on the sensitive communities along the highway route, the Department of Highways, therefore, designs a new technique for installing noise barrier on the sensitive areas, i.e. education institutions, temple, residential area. In addition, the mathematic model is applied to 12 selected locations of sensitive areas for monitoring the effectiveness of the new installation technique. The mathematic model is used for predict the future noise level after installation of noise barrier in year 2037. The results confirm that the appropriate height and width of noise barrier can improve the comfortable of the people on the sensitive area.

  14. Croatian Experience in Road Traffic Noise Management - Concrete Noise Barriers

    Directory of Open Access Journals (Sweden)

    Ahac Saša

    2014-07-01

    Full Text Available The paper gives an overview of concrete noise barrier application in several EU countries and in Croatia. It describes a process of introducing different noise protection solutions on Croatian market in the phase of intensive motorway construction in recent years. Namely, an extensive motorway network has been constructed in Croatia in the last 10 years. Following the process of motorway construction, noise protection walls have also been erected. Usage of different building materials and installation processes as well as variations in building expenditures has led to a comparative analysis of several types of noise protection solutions (expanded clay, wood fibre including a new eco-innovative product RUCONBAR, which incorporates rubber granules from recycled waste tyres to form a porous noise absorptive layer.

  15. Control strategies for active noise barriers using near-field error sensing

    NARCIS (Netherlands)

    Berkhoff, Arthur P.

    In this paper active noise control strategies for noise barriers are presented which are based on the use of sensors near the noise barrier. Virtual error signals are derived from these near-field sensor signals such that reductions of the far-field sound pressure are obtained with the active

  16. Research on the application of active sound barriers for the transformer noise abatement

    Directory of Open Access Journals (Sweden)

    Hu Sheng

    2016-01-01

    Full Text Available Sound barriers are a type of measure most commonly used in the noise abatement of transformers. In the noise abatement project of substations, the design of sound barriers is restrained by the portal frames which are used to hold up outgoing lines from the main transformers, which impacts the noise reduction effect. If active sound barriers are utilized in these places, the noise diffraction of sound barriers can be effectively reduced. At a 110kV Substation, an experiment using a 15-channel active sound barrier has been carried out. The result of the experiment shows that the mean noise reduction value (MNRV of the noise measuring points at the substation boundary are 1.5 dB (A. The effect of the active noise control system is impacted by the layout of the active noise control system, the acoustic environment on site and the spectral characteristic of the target area.

  17. Barrier inhomogeneities limited current and 1/f noise transport in GaN based nanoscale Schottky barrier diodes

    Science.gov (United States)

    Kumar, Ashutosh; Heilmann, M.; Latzel, Michael; Kapoor, Raman; Sharma, Intu; Göbelt, M.; Christiansen, Silke H.; Kumar, Vikram; Singh, Rajendra

    2016-01-01

    The electrical behaviour of Schottky barrier diodes realized on vertically standing individual GaN nanorods and array of nanorods is investigated. The Schottky diodes on individual nanorod show highest barrier height in comparison with large area diodes on nanorods array and epitaxial film which is in contrast with previously published work. The discrepancy between the electrical behaviour of nanoscale Schottky diodes and large area diodes is explained using cathodoluminescence measurements, surface potential analysis using Kelvin probe force microscopy and 1ow frequency noise measurements. The noise measurements on large area diodes on nanorods array and epitaxial film suggest the presence of barrier inhomogeneities at the metal/semiconductor interface which deviate the noise spectra from Lorentzian to 1/f type. These barrier inhomogeneities in large area diodes resulted in reduced barrier height whereas due to the limited role of barrier inhomogeneities in individual nanorod based Schottky diode, a higher barrier height is obtained. PMID:27282258

  18. Regulatory barriers blocking standardization of interoperability.

    Science.gov (United States)

    Zhong, Daidi; Kirwan, Michael J; Duan, Xiaolian

    2013-07-12

    Developing and implementing a set of personal health device interoperability standards is key to cultivating a healthy global industry ecosystem. The standardization organizations, including the Institute of Electrical and Electronics Engineers 11073 Personal Health Device Workgroup (IEEE 11073-PHD WG) and Continua Health Alliance, are striving for this purpose. However, factors like the medial device regulation, health policy, and market reality have placed non-technical barriers over the adoption of technical standards throughout the industry. These barriers have significantly impaired the motivations of consumer device vendors who desire to enter the personal health market and the overall success of personal health industry ecosystem. In this paper, we present the affect that these barriers have placed on the health ecosystem. This requires immediate action from policy makers and other stakeholders. The current regulatory policy needs to be updated to reflect the reality and demand of consumer health industry. Our hope is that this paper will draw wide consensus amongst its readers, policy makers, and other stakeholders.

  19. BARRIER DESIGN STRATEGIES TO CONTROL NOISE INGRESS INTO DOMESTIC BUILDINGS

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    Christina E. Mediastika

    2003-01-01

    Full Text Available Noise source for buildings adjacent to streets is traffic-generated predominantly. Where people are mostly spend their time indoors, it is important for buildings to have screening or blocking to control noise intrusion into living spaces. But this blocking should also permit airflow. This is important for middle to low-cost domestic buildings, which do not employ conditioned ventilation. A common feature of Indonesian buildings, fence, is studied to perform noise barrier. The fence -a barrier to be- should obey three factors: position, dimension, and material. All these three factors were studied to seek compromised design for acoustic performance and natural ventilation purpose. Domestic building situated in the urban area of Yogyakarta was studying to see the most possible design of the barrier to be. There are two calculation methods employed to investigate the proposed design. The study shows that it is possible to gain minimum of 10 dB noise reduction by placing windows within the shadow effect of approximately 1.5 height fence-barrier.

  20. The Analysis of Low Noise Protection Barriers Influence on Tram Traffic Noise Levels

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    Ahac Maja

    2013-07-01

    Full Text Available The paper describes the analysis of tram traffic noise situation in residential areas in the vicinity of Drzic Avenue, one of the major routes between the northern and southern part of the Croatian capital city Zagreb, and the effect of low barriers placed by the tracks on tram noise mitigation. In order to evaluate the effect of planned protection measure, noise models were produced and verified with short-term field measurements. Calculations were conducted by means of noise prediction software, using European interim noise prediction method and 3D model of analyzed area. Finally, the results of noise calculations for existing tram traffic situation and planned measure of protection are presented on noise maps.

  1. Influence of solid noise barriers on near-road and on-road air quality

    Science.gov (United States)

    Baldauf, Richard W.; Isakov, Vlad; Deshmukh, Parikshit; Venkatram, Akula; Yang, Bo; Zhang, K. Max

    2016-03-01

    Public health concerns regarding adverse health effects for populations spending significant amounts of time near high traffic roadways has increased substantially in recent years. Roadside features, including solid noise barriers, have been investigated as potential methods that can be implemented in a relatively short time period to reduce air pollution exposures from nearby traffic. A field study was conducted to determine the influence of noise barriers on both on-road and downwind pollutant concentrations near a large highway in Phoenix, Arizona, USA. Concentrations of nitrogen dioxide, carbon monoxide, ultrafine particles, and black carbon were measured using a mobile platform and fixed sites along two limited-access stretches of highway that contained a section of noise barrier and a section with no noise barrier at-grade with the surrounding terrain. Results of the study showed that pollutant concentrations behind the roadside barriers were significantly lower relative to those measured in the absence of barriers. The reductions ranged from 50% within 50 m from the barrier to about 30% as far as 300 m from the barrier. Reductions in pollutant concentrations generally began within the first 50 m of the barrier edge; however, concentrations were highly variable due to vehicle activity behind the barrier and along nearby urban arterial roadways. The concentrations on the highway, upwind of the barrier, varied depending on wind direction. Overall, the on-road concentrations in front of the noise barrier were similar to those measured in the absence of the barrier, contradicting previous modeling results that suggested roadside barriers increase pollutant levels on the road. Thus, this study suggests that noise barriers do reduce potential pollutant exposures for populations downwind of the road, and do not likely increase exposures to traffic-related pollutants for vehicle passengers on the highway.

  2. Far field effects of complex noise barrier reflections

    NARCIS (Netherlands)

    Lutgendorf, D.; Wessels, P.W.; Eerden, F.J.M. van den; Roo, F. de

    2012-01-01

    Within the EU FP7 QUIESST project, QUIeting the Environment for a Sustainable Surface Transport, a test method is being developed for the reflectivity of noise barriers. The method needs to account for a complex shape of barriers and the use of various types of absorbing materials. The performance

  3. Collapse models with non-white noises

    International Nuclear Information System (INIS)

    Adler, Stephen L; Bassi, Angelo

    2007-01-01

    We set up a general formalism for models of spontaneous wavefunction collapse with dynamics represented by a stochastic differential equation driven by general Gaussian noises, not necessarily white in time. In particular, we show that the non-Schroedinger terms of the equation induce the collapse of the wavefunction to one of the common eigenstates of the collapsing operators, and that the collapse occurs with the correct quantum probabilities. We also develop a perturbation expansion of the solution of the equation with respect to the parameter which sets the strength of the collapse process; such an approximation allows one to compute the leading-order terms for the deviations of the predictions of collapse models with respect to those of standard quantum mechanics. This analysis shows that to leading order, the 'imaginary noise' trick can be used for non-white Gaussian noise

  4. Regulatory Barriers Blocking Standardization of Interoperability

    OpenAIRE

    Zhong, Daidi; Kirwan, Michael J; Duan, Xiaolian

    2013-01-01

    Developing and implementing a set of personal health device interoperability standards is key to cultivating a healthy global industry ecosystem. The standardization organizations, including the Institute of Electrical and Electronics Engineers 11073 Personal Health Device Workgroup (IEEE 11073-PHD WG) and Continua Health Alliance, are striving for this purpose. However, factors like the medial device regulation, health policy, and market reality have placed non-technical barriers over the ad...

  5. ON THE APPLICATION OF PARTIAL BARRIERS FOR SPINNING MACHINE NOISE CONTROL: A THEORETICAL AND EXPERIMENTAL APPROACH

    Directory of Open Access Journals (Sweden)

    M. R. Monazzam, A. Nezafat

    2007-04-01

    Full Text Available Noise is one of the most serious challenges in modern community. In some specific industries, according to the nature of process, this challenge is more threatening. This paper describes a means of noise control for spinning machine based on experimental measurements. Also advantages and disadvantages of the control procedure are added. Different factors which may affect the performance of the barrier in this situation are also mentioned. To provide a good estimation of the control measure, a theoretical formula is also described and it is compared with the field data. Good agreement between the results of filed measurements and theoretical presented model was achieved. No obvious noise reduction was seen by partial indoor barriers in low absorbent enclosed spaces, since the reflection from multiple hard surfaces is the main dominated factor in the tested environment. At the end, the situation of the environment and standards, which are necessary in attaining the ideal results, are explained.

  6. 40 CFR 205.52 - Vehicle noise emission standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Vehicle noise emission standards. 205... ABATEMENT PROGRAMS TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Medium and Heavy Trucks § 205.52 Vehicle noise emission standards. (a) Low Speed Noise Emission Standard. Vehicles which are manufactured after...

  7. Radio-frequency shot-noise measurement in a magnetic tunnel junction with a MgO barrier

    International Nuclear Information System (INIS)

    Rehman, Mushtaq; Park, Junghwan; Song, Woon; Chong, Yonuk; Lee, Yeonsub; Min, Byoungchul; Shin, Kyungho; Ryu, Sangwan; Khim, Zheong

    2010-01-01

    We measured the noise power of a magnetic tunnel junction in the frequency range of 710 ∼ 1200 MHz. A low-noise cryogenic HEMT amplifier was used to measure the small noise signal at a high frequency with wide bandwidth. The MgO-barrier tunnel junction showed large tunnel magnetoresistance ratio of 215% at low temperature, which indicates electronic transport through the tunnel barrier without any significant spin-flip scattering. In the bias-dependent noise measurement, however, the zero-bias shot noise was enhanced compared to the value expected from a perfect tunnel barrier or the value observed from a good Al-AlO x -Al tunnel junction. We assume that this enhanced noise comes from inelastic tunneling processes through the barrier, which may be related to the observed zero-bias anomaly in the differential resistance of the tunnel junctions. We present a simple phenomenological model for how the inelastic scattering process can enhance the zero-bias noise in a tunnel junction.

  8. Schottky barrier parameters and low frequency noise characteristics of graphene-germanium Schottky barrier diode

    Science.gov (United States)

    Khurelbaatar, Zagarzusem; Kil, Yeon-Ho; Shim, Kyu-Hwan; Cho, Hyunjin; Kim, Myung-Jong; Lee, Sung-Nam; Jeong, Jae-chan; Hong, Hyobong; Choi, Chel-Jong

    2016-03-01

    We investigated the electrical properties of chemical vapor deposition-grown monolayer graphene/n-type germanium (Ge) Schottky barrier diodes (SBD) using current-voltage (I-V) characteristics and low frequency noise measurements. The Schottky barrier parameters of graphene/n-type Ge SBDs, such as Schottky barrier height (VB), ideality factor (n), and series resistance (Rs), were extracted using the forward I-V and Cheung's methods. The VB and n extracted from the forward ln(I)-V plot were found to be 0.63 eV and 1.78, respectively. In contrast, from Cheung method, the VB and n were calculated to be 0.53 eV and 1.76, respectively. Such a discrepancy between the values of VB calculated from the forward I-V and Cheung's methods indicated a deviation from the ideal thermionic emission of graphene/n-type Ge SBD associated with the voltage drop across graphene. The low frequency noise measurements performed at the frequencies in the range of 10 Hz-1 kHz showed that the graphene/n-type Ge SBD had 1/f γ frequency dependence, with γ ranging from 1.09 to 1.12, regardless of applied forward biases. Similar to forward-biased SBDs operating in the thermionic emission mode, the current noise power spectral density of graphene/n-type Ge SBD was linearly proportional to the forward current.

  9. Reconfigurable origami sonic barriers with tunable bandgaps for traffic noise mitigation

    Science.gov (United States)

    Thota, M.; Wang, K. W.

    2017-10-01

    An origami sonic barrier composed of cylindrical inclusions attached onto an origami sheet is proposed. The idea allows for tunable sound blocking properties for application in attenuating complex traffic noise spectra. Folding of the underlying origami sheet transforms the periodicity of the inclusions between different Bravais lattices, viz. between a square and a hexagonal lattice, and such significant lattice re-configuration leads to drastic tuning of dispersion characteristics. The wave tuning capabilities are corroborated via performing theoretical and numerical investigations using a plane wave expansion method and an acoustic simulation package of COMSOL, while experiments are performed on a one-seventh scaled-down model of origami sonic barrier to demonstrate the lattice re-configuration between different Bravais lattices and the associated bandgap adaptability. Good sound blocking performance in the frequency range of traffic noise spectra combined with less efforts, required for actuating one-degree of freedom folding mechanism, makes the origami sonic barrier a potential candidate for mitigating complex traffic noise.

  10. Pumped shot noise in adiabatically modulated graphene-based double-barrier structures.

    Science.gov (United States)

    Zhu, Rui; Lai, Maoli

    2011-11-16

    Quantum pumping processes are accompanied by considerable quantum noise. Based on the scattering approach, we investigated the pumped shot noise properties in adiabatically modulated graphene-based double-barrier structures. It is found that compared with the Poisson processes, the pumped shot noise is dramatically enhanced where the dc pumped current changes flow direction, which demonstrates the effect of the Klein paradox.

  11. Pumped shot noise in adiabatically modulated graphene-based double-barrier structures

    Science.gov (United States)

    Zhu, Rui; Lai, Maoli

    2011-11-01

    Quantum pumping processes are accompanied by considerable quantum noise. Based on the scattering approach, we investigated the pumped shot noise properties in adiabatically modulated graphene-based double-barrier structures. It is found that compared with the Poisson processes, the pumped shot noise is dramatically enhanced where the dc pumped current changes flow direction, which demonstrates the effect of the Klein paradox.

  12. Combined acoustical and visual performance of noise barriers in mitigating the environmental impact of motorways.

    Science.gov (United States)

    Jiang, Like; Kang, Jian

    2016-02-01

    This study investigated the overall performance of noise barriers in mitigating environmental impact of motorways, taking into consideration their effects on reducing noise and visual intrusions of moving traffic, but also potentially inducing visual impact themselves. A laboratory experiment was carried out, using computer-visualised video scenes and motorway traffic noise recordings to present experimental scenarios covering two traffic levels, two distances of receiver to road, two types of background landscape, and five barrier conditions including motorway only, motorway with tree belt, motorways with 3 m timber barrier, 5m timber barrier, and 5m transparent barrier. Responses from 30 participants of university students were gathered and perceived barrier performance analysed. The results show that noise barriers were always beneficial in mitigating environmental impact of motorways, or made no significant changes in environmental quality when the impact of motorways was low. Overall, barriers only offered similar mitigation effect as compared to tree belt, but showed some potential to be more advantageous when traffic level went high. 5m timber barrier tended to perform better than the 3m one at the distance of 300 m but not at 100 m possibly due to its negative visual effect when getting closer. The transparent barrier did not perform much differently from the timber barriers but tended to be the least effective in most scenarios. Some low positive correlations were found between aesthetic preference for barriers and environmental impact reduction by the barriers. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Toward the detection of gravitational waves under non-Gaussian noises I. Locally optimal statistic.

    Science.gov (United States)

    Yokoyama, Jun'ichi

    2014-01-01

    After reviewing the standard hypothesis test and the matched filter technique to identify gravitational waves under Gaussian noises, we introduce two methods to deal with non-Gaussian stationary noises. We formulate the likelihood ratio function under weakly non-Gaussian noises through the Edgeworth expansion and strongly non-Gaussian noises in terms of a new method we call Gaussian mapping where the observed marginal distribution and the two-body correlation function are fully taken into account. We then apply these two approaches to Student's t-distribution which has a larger tails than Gaussian. It is shown that while both methods work well in the case the non-Gaussianity is small, only the latter method works well for highly non-Gaussian case.

  14. Numerical simulation of the sound reflection effects of noise barriers in near and far field

    NARCIS (Netherlands)

    Lutgendorf, D.; Roo, F. de; Eerden, F.J.M. van der; Jean, P.; Ecotière, D.; Dutilleux, G.

    2011-01-01

    This paper deals with the first stages of the development of a new test method for evaluating the reflectivity performance of noise barriers. The reflectivity performance describes the increase in sound level at a receiver due to the presence of the noise barrier. First the current test method for

  15. Electron transport and noise spectroscopy in organic magnetic tunnel junctions with PTCDA and Alq3 barriers

    Science.gov (United States)

    Martinez, Isidoro; Cascales, Juan Pedro; Hong, Jhen-Yong; Lin, Minn-Tsong; Prezioso, Mirko; Riminucci, Alberto; Dediu, Valentin A.; Aliev, Farkhad G.

    2016-10-01

    The possible influence of internal barrier dynamics on spin, charge transport and their fluctuations in organic spintronics remains poorly understood. Here we present investigation of the electron transport and low frequency noise at temperatures down to 0.3K in magnetic tunnel junctions with an organic PTCDA barriers with thickness up to 5 nm in the tunneling regime and with 200 nm thick Alq3 barrier in the hopping regime. We observed high tunneling magneto-resistance at low temperatures (15-40%) and spin dependent super-poissonian shot noise in organic magnetic tunnel junctions (OMTJs) with PTCDA. The Fano factor exceeds 1.5-2 values which could be caused by interfacial states controlled by spin dependent bunching in the tunneling events through the molecules.1 The bias dependence of the low frequency noise in OMTJs with PTCDA barriers which includes both 1/f and random telegraph noise activated at specific biases will also be discussed. On the other hand, the organic junctions with ferromagnetic electrodes and thick Alq3 barriers present sub-poissonian shot noise which depends on the temperature, indicative of variable range hopping.

  16. Application of flexi-wall in noise barriers renewal

    Directory of Open Access Journals (Sweden)

    B. Daee

    2015-12-01

    Full Text Available This paper presents an experimental study on structural performance of an innovative noise barrier consisting of poly-block, light polyurethane foam (LPF and polyurea. This wall system (flexi-wall is intended to be employed as a vertical extension to existing noise barriers (sound walls in an accelerated construction method. To aid in the wall design, several mechanical tests were conducted on LPF specimens and two full-scale walls were then fabricated employing the same LPF material. The full-scale walls were subjected to lateral loading in order to establish their lateral resistance. A cyclic fatigue test was also performed on a full-scale flexi-wall in order to evaluate the performance of the wall under a repetitive loading condition. The results of the experiments indicated the suitability of flexi-wall in accelerated construction and confirmed that the structural performance of the wall system under lateral loading is satisfactory for the sound wall application. The experimental results were discussed and a preliminary design procedure for application of flexi-wall in sound wall applications was also developed.

  17. An investigation on the noise reduction performance of profiled rigid median barriers at highways

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Monazzam

    2012-01-01

    Full Text Available Median barriers as a portion of a divided highway are provided to minimize the cross-median crashes. Moreover, median barriers similar to roadside noise barriers could protect people from transportation noise. Thus, there is a need to investigate various median barrier models to identify changes of insertion loss over a simple rigid barrier. In order to estimate the acoustical influence of median barrier′s profile in the shadow zone, different median barrier models are presented and their insertion losses are calculated over a frequency range from 50 to 4000 Hz using a two-dimensional boundary element method. The present investigation has clearly revealed that among the profiled median barriers, T-shape, Y-shape, and L-shape provide better performance than that of the other shapes. It is also found that among inclined barriers, V-shape barrier significantly presents higher values of attenuation. Based on the calculation of different geometrics, it has been shown that a further 2 dB (A in efficiency could be obtained by a better design of the median barrier which is labeled model "L."

  18. The Influence of Visibility Conditions in Horizontal Road Curves on the Efficiency of Noise Protection Barriers

    Directory of Open Access Journals (Sweden)

    Džambas Tamara

    2013-12-01

    Full Text Available Ensuring sufficient visibility on planned roads by sight distance testing is an integral part of every project, but problems with visibility can emerge when noise barriers are erected on existing roads. Namely, in order to provide sufficient noise protection, high noise barriers are often placed at minimum distance from the carriageway edge, and additional visibility testing in most cases is not carried out.

  19. Temperature dependence of shot noise in double barrier magnetic tunnel junctions

    Science.gov (United States)

    Niu, Jiasen; Liu, Liang; Feng, J. F.; Han, X. F.; Coey, J. M. D.; Zhang, X.-G.; Wei, Jian

    2018-03-01

    Shot noise reveals spin dependent transport properties in a magnetic tunnel junction. We report measurement of shot noise in CoFeB/MgO/CoFeB/MgO/CoFeB double barrier magnetic tunnel junctions, which shows a strong temperature dependence. The Fano factor used to characterize shot noise increases with decreasing temperature. A sequential tunneling model can be used to account for these results, in which a larger Fano factor results from larger spin relaxation length at lower temperatures.

  20. A Comprehensive Review on the Effectiveness of Existing Noise Barriers commonly used in the Railway Industry

    Directory of Open Access Journals (Sweden)

    Shahidan Shahiron

    2017-01-01

    Full Text Available Nowadays, advanced development and sophisticated new technology have led to various types of environmental pollution such as water, air, land, thermal pollution and so on. Recently, however, noise pollution is becoming one of the major threats to the world especially in urban areas where it adversely affects the quality of life of the public. In Malaysia, the Department of Environment has identified that the average transportation noise levels in major cities in peninsular Malaysia are 71.6 dB (A and 70.4 dB (A during the day and night respectively. The noise is usually emitted by airplanes, trains, vehicles, motorcycles, trucks and etc. Even though rail transport requires less energy and emits less hazardous substances, it has contributed to noise pollution issues and several health hazards among urban inhabitants such as deafness, nervous breakdowns, mental disorder, heart troubles, high blood pressure, headaches, dizziness, inefficiency and insomnia. Therefore, many studies attempt to reduce noise pollution by applying noise barriers at noise polluted areas via various approaches. This paper aims to explore the effectiveness of noise barriers using noise absorption performance due to several factors such as type of absorbent materials, material thickness, density, porosity and design. This research has found that the thicker the specimen and the denser the absorbent material, the better the sound absorption performance. Besides that, barrier design also plays a major role in determining its effectiveness, where the effectiveness of noise barriers should be high and long enough to break the line-of-sight between the sound source and the receiver. There are several methods that can be used to measure the effectiveness of noise barriers such as the Adrienne Method (in-situ measurement method and impedance tube method (laboratory measurement method to measure the acoustic absorption. Nevertheless, the impedance tube measurement method provides

  1. Assessment and Mitigation of the Effects of Noise on Habitability in Deep Space Environments: Report on Non-Auditory Effects of Noise

    Science.gov (United States)

    Begault, Durand R.

    2018-01-01

    This document reviews non-auditory effects of noise relevant to habitable volume requirements in cislunar space. The non-auditory effects of noise in future long-term space habitats are likely to be impactful on team and individual performance, sleep, and cognitive well-being. This report has provided several recommendations for future standards and procedures for long-term space flight habitats, along with recommendations for NASA's Human Research Program in support of DST mission success.

  2. Low frequency noise in semiconductor detectors

    International Nuclear Information System (INIS)

    Stojanovic, M.; Marjanovic, N.

    1998-01-01

    Noise characteristics of surface-barrier detectors based on Au contacts on n-Si were measured and analyzed. The metal layers were deposited by evaporation to 40-100 nm thickness. Standard surface-barrier detectors based on Au/Si structures are known to have favorable characteristics, but they tend to degrade with aging and under severe working conditions. Degradation is particularly related to the increase in noise level, leakage current and the reduction of detector efficiency and resolution. Therefore, practical applications of surface-barrier detectors demand their constant upgrading. Improvements of detector properties are concentrated mainly on the front surface and front (rectifying) contact. The aim was to improve the noise characteristics of the surface-barrier structures and retain the favorable detector properties of the Au/Si system. (authors)

  3. Reduction of Non-stationary Noise using a Non-negative Latent Variable Decomposition

    DEFF Research Database (Denmark)

    Schmidt, Mikkel Nørgaard; Larsen, Jan

    2008-01-01

    We present a method for suppression of non-stationary noise in single channel recordings of speech. The method is based on a non-negative latent variable decomposition model for the speech and noise signals, learned directly from a noisy mixture. In non-speech regions an over complete basis...... is learned for the noise that is then used to jointly estimate the speech and the noise from the mixture. We compare the method to the classical spectral subtraction approach, where the noise spectrum is estimated as the average over non-speech frames. The proposed method significantly outperforms...

  4. Effect of noise on the standard mapping

    International Nuclear Information System (INIS)

    Karney, C.F.F.; Rechester, A.B.; White, R.B.

    1981-03-01

    The effect of a small amount of noise on the standard mapping is considered. Whenever the standard mapping possesses accelerator models (where the action increases approximately linearly with time), the diffusion coefficient contains a term proportional to the reciprocal of the variance of the noise term. At large values of the stochasticity parameter, the accelerator modes exhibit a universal behavior. As a result the dependence of the diffusion coefficient on stochasticity parameter also shows some universal behavior

  5. Interlamellar cracking of thermal barrier coatings with TGOs by non-standard four-point bending tests

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, P.F. [State Key Laboratory for Strength and Vibration, Department of Engineering Mechanics, Xi' an Jiaotong University, Xi' an (China); Li, X.D. [State Key Laboratory for Strength and Vibration, Department of Engineering Mechanics, Xi' an Jiaotong University, Xi' an (China); Aircraft Strength Research Institute of China, Xi' an, 710065 (China); Shang, F.L., E-mail: shangfl@mail.xjtu.edu.cn [State Key Laboratory for Strength and Vibration, Department of Engineering Mechanics, Xi' an Jiaotong University, Xi' an (China); Li, C.J. [State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi' an Jiaotong University, Xi' an (China)

    2011-09-25

    Highlights: {yields} A non-standard modified four-point bending specimen is adopted for delamination test. {yields} Typical failure mode of the TBC system with TGO layer is demonstrated. {yields} Fracture toughness of 8YSZ on a cold-sprayed MCrAlY coating is evaluated theoretically. - Abstract: This work concerns the failure mode and fracture toughness of plasma-sprayed 8 wt% yttria-stabilized zirconia (8YSZ) deposited on a cold-sprayed MCrAlY bond coat (BC) after thermal oxidation. Upon high-temperature exposure, a thermally grown oxide (TGO) layer was formed along the interface between the BC layer and YSZ ceramic coating layer through oxidation of the bond coat. By utilizing a non-standard modified four-point bending specimen, in conjunction with fractured surface examinations by scanning electron microscope and energy disperse spectroscope, the failure mode of this thermal barrier coating (TBC) system has been checked experimentally. It is shown that delamination cracks firstly initiate at the YSZ/BC interface edge, and then propagate along a wavy path near the interface, not only through the TBC but also within the TGO and along the interlamellar interfaces. Through a theoretical analysis of the bending specimen, the fracture toughness of this TBC system, in terms of strain energy release rate, has been determined from the load-displacement curves which were recorded during the tests.

  6. Anomalous barrier escape: The roles of noise distribution and correlation

    Science.gov (United States)

    Hu, Meng; Zhang, Jia-Ming; Bao, Jing-Dong

    2017-05-01

    We study numerically and analytically the barrier escape dynamics of a particle driven by an underlying correlated Lévy noise for a smooth metastable potential. A "quasi-monochrome-color" Lévy noise, i.e., the first-order derivative variable of a linear second-order differential equation subjected to a symmetric α-stable white Lévy noise, also called the harmonic velocity Lévy noise, is proposed. Note that the time-integral of the noise Green function of this kind is equal to zero. This leads to the existence of underlying negative time correlation and implies that a step in one direction is likely followed by a step in the other direction. By using the noise of this kind as a driving source, we discuss the competition between long flights and underlying negative correlations in the metastable dynamics. The quite rich behaviors in the parameter space including an optimum α for the stationary escape rate have been found. Remarkably, slow diffusion does not decrease the stationary rate while a negative correlation increases net escape. An approximate expression for the Lévy-Kramers rate is obtained to support the numerically observed dependencies.

  7. A sensitivity-based approach to optimize the surface treatment of a low-height tramway noise barrier

    Science.gov (United States)

    Jolibois, Alexandre

    Transportation noise has become a main nuisance in urban areas, in the industrialized world and across the world, to the point that according to the World Health Organization 65% of the European population is exposed to excessive noise and 20% to night-time levels that may harm their health. There is therefore a need to find new ways to mitigate transportation noise in urban areas. In this work, a possible device to achieve this goal is studied: a low-height noise barrier. It consists of a barrier typically less than one meter high placed close to the source, designed to decrease significantly the noise level for nearby pedestrians and cyclists. A numerical method which optimizes the surface treatment of a low-height barrier in order to increase its insertion loss is presented. Tramway noise barriers are especially studied since the noise sources are in this case close to the ground and would be attenuated more by the barrier. The acoustic behavior of the surface treatment is modeled via its admittance. It can be itself described by a few parameters (flow resistivity, geometrical dimensions...), which can then be optimized. It is proposed to couple porous layers and micro-perforated panel (MPP) resonators in order to take advantage of their different acoustic properties. Moreover, the optimization is achieved using a sensitivity-based method, since in this framework the gradient of the attenuation can be evaluated accurately and efficiently. Several shapes are considered: half-cylinder, quarter-cylinder, straight wall, T-shape and square shape. In the case of a half-cylindrical geometry, a semi-analytical solution for the sound field in terms of a series of cylindrical waves is derived, which simplifies the sensitivity calculation and optimization process. The boundary element method (BEM) is used to evaluate the attenuation for the remaining shapes, and in this case the sensitivity is evaluated using the adjoint state approach. For all considered geometries, it is

  8. Implementation of a Non-Metallic Barrier in an Electric Motor

    Science.gov (United States)

    M?Sadoques, George; Carra, Michael; Beringer, Woody

    2012-01-01

    Electric motors that run in pure oxygen must be sealed, or "canned," for safety reasons to prevent the oxygen from entering into the electrical portion of the motor. The current canning process involves designing a metallic barrier around the rotor to provide the separation. This metallic barrier reduces the motor efficiency as speed is increased. In higher-speed electric motors, efficiency is greatly improved if a very thin, nonmetallic barrier can be utilized. The barrier thickness needs to be approximately 0.025-in. (.0.6-mm) thick and can be made of a brittle material such as glass. The motors, however, designed for space applications are typically subject to high-vibration environments. A fragile, non-metallic barrier can be utilized in a motor assembly if held in place by a set of standard rubber O-ring seals. The O-rings provide the necessary sealing to keep oxygen away from the electrical portion of the motor and also isolate the fragile barrier from the harsh motor vibration environment. The compliance of the rubber O-rings gently constrains the fragile barrier and isolates it from the harsh external motor environment. The use of a non-metallic barrier greatly improves motor performance, especially at higher speeds, while isolating the electronics from the working fluid with an inert liner.

  9. Current inversion induced by colored non-Gaussian noise

    International Nuclear Information System (INIS)

    Bag, Bidhan Chandra; Hu, Chin-Kung

    2009-01-01

    We study a stochastic process driven by colored non-Gaussian noises. For the flashing ratchet model we find that there is a current inversion in the variation of the current with the half-cycle period which accounts for the potential on–off operation. The current inversion almost disappears if one switches from non-Gaussian (NG) to Gaussian (G) noise. We also find that at low value of the asymmetry parameter of the potential the mobility controlled current is more negative for NG noise as compared to G noise. But at large magnitude of the parameter the diffusion controlled positive current is higher for the former than for the latter. On increasing the noise correlation time (τ), keeping the noise strength fixed, the mean velocity of a particle first increases and then decreases after passing through a maximum if the noise is non-Gaussian. For Gaussian noise, the current monotonically decreases. The current increases with the noise parameter p, 0< p<5/3, which is 1 for Gaussian noise

  10. Stochastic resonance in a piecewise nonlinear model driven by multiplicative non-Gaussian noise and additive white noise

    Science.gov (United States)

    Guo, Yongfeng; Shen, Yajun; Tan, Jianguo

    2016-09-01

    The phenomenon of stochastic resonance (SR) in a piecewise nonlinear model driven by a periodic signal and correlated noises for the cases of a multiplicative non-Gaussian noise and an additive Gaussian white noise is investigated. Applying the path integral approach, the unified colored noise approximation and the two-state model theory, the analytical expression of the signal-to-noise ratio (SNR) is derived. It is found that conventional stochastic resonance exists in this system. From numerical computations we obtain that: (i) As a function of the non-Gaussian noise intensity, the SNR is increased when the non-Gaussian noise deviation parameter q is increased. (ii) As a function of the Gaussian noise intensity, the SNR is decreased when q is increased. This demonstrates that the effect of the non-Gaussian noise on SNR is different from that of the Gaussian noise in this system. Moreover, we further discuss the effect of the correlation time of the non-Gaussian noise, cross-correlation strength, the amplitude and frequency of the periodic signal on SR.

  11. Standards for the Protection of Skin Barrier Function.

    Science.gov (United States)

    Giménez-Arnau, Ana

    2016-01-01

    The skin is a vital organ, and through our skin we are in close contact with the entire environment. If we lose our skin we lose our life. The barrier function of the skin is mainly driven by the sophisticated epidermis in close relationship with the dermis. The epidermal epithelium is a mechanically, chemically, biologically and immunologically active barrier submitted to continuous turnover. The barrier function of the skin needs to be protected and restored. Its own physiology allows its recovery, but many times this is not sufficient. This chapter is focused on the standards to restore, treat and prevent barrier function disruption. These standards were developed from a scientific, academic and clinical point of view. There is a lack of standardized administrative recommendations. Still, there is a walk to do that will help to reduce the social and economic burden of diseases characterized by an abnormal skin barrier function. © 2016 S. Karger AG, Basel.

  12. Impact of noise barriers on the dispersal of solid pollutants from car emissions and their deposition in soil

    Directory of Open Access Journals (Sweden)

    Wawer Małgorzata

    2017-03-01

    Full Text Available Despite the existence of various methods aimed at protecting the environment from the negative influence of roads, there is a lack of adequate techniques for monitoring and reducing the spread of roadside pollution into the air and soils. The aim of this study was to assess the impact of noise barriers (sound walls on the dispersal and soil deposition of solid pollutants from car emissions, based on both quantitative and qualitative analysis. Magnetic susceptibility measurements, trace elements analyses, and platinum (Pt and rhodium (Rh content determinations were performed on soil samples collected in the vicinity of various types of noise barrier. Previous investigations have shown that most traffic emissions are deposited in the close vicinity of roads (up to 10 m, with pollution levels decreasing with increasing distance from the road edge. However, the results of the present study indicate that this distribution is disturbed in areas in which noise barriers are located. Moreover, additional soil enrichment with trace elements was observed at approx. 10-15 m behind the barriers. The spatial distribution of trace elements contents in the tested soil samples corresponded to the magnetic susceptibility values. High Fe, Zn, Mn and Pb levels were observed adjacent to noise barriers composed of sawdust concrete and steel panels.

  13. Tunnel barrier and noncollinear magnetization effects on shot noise in ferromagnetic/semiconductor/ferromagnetic heterojunctions

    International Nuclear Information System (INIS)

    An Xingtao; Liu Jianjun

    2008-01-01

    Based on the scattering approach, we investigate transport properties of electrons in a one-dimensional waveguide that contains a ferromagnetic/semiconductor/ferromagnetic heterojunction and tunnel barriers in the presence of Rashba and Dresselhaus spin-orbit interactions. We simultaneously consider significant quantum size effects, quantum coherence, Rashba and Dresselhaus spin-orbit interactions and noncollinear magnetizations. It is found that the tunnel barrier plays a decisive role in the transmission coefficient and shot noise of the ballistic spin electron transport through the heterojunction. When the small tunnel barriers are considered, the transport properties of electrons are quite different from those without tunnel barriers

  14. Non-monotonic probability of thermal reversal in thin-film biaxial nanomagnets with small energy barriers

    Directory of Open Access Journals (Sweden)

    N. Kani

    2017-05-01

    Full Text Available The goal of this paper is to investigate the short time-scale, thermally-induced probability of magnetization reversal for an biaxial nanomagnet that is characterized with a biaxial magnetic anisotropy. For the first time, we clearly show that for a given energy barrier of the nanomagnet, the magnetization reversal probability of an biaxial nanomagnet exhibits a non-monotonic dependence on its saturation magnetization. Specifically, there are two reasons for this non-monotonic behavior in rectangular thin-film nanomagnets that have a large perpendicular magnetic anisotropy. First, a large perpendicular anisotropy lowers the precessional period of the magnetization making it more likely to precess across the x^=0 plane if the magnetization energy exceeds the energy barrier. Second, the thermal-field torque at a particular energy increases as the magnitude of the perpendicular anisotropy increases during the magnetization precession. This non-monotonic behavior is most noticeable when analyzing the magnetization reversals on time-scales up to several tens of ns. In light of the several proposals of spintronic devices that require data retention on time-scales up to 10’s of ns, understanding the probability of magnetization reversal on the short time-scales is important. As such, the results presented in this paper will be helpful in quantifying the reliability and noise sensitivity of spintronic devices in which thermal noise is inevitably present.

  15. Image reconstruction under non-Gaussian noise

    DEFF Research Database (Denmark)

    Sciacchitano, Federica

    During acquisition and transmission, images are often blurred and corrupted by noise. One of the fundamental tasks of image processing is to reconstruct the clean image from a degraded version. The process of recovering the original image from the data is an example of inverse problem. Due...... to the ill-posedness of the problem, the simple inversion of the degradation model does not give any good reconstructions. Therefore, to deal with the ill-posedness it is necessary to use some prior information on the solution or the model and the Bayesian approach. Additive Gaussian noise has been......D thesis intends to solve some of the many open questions for image restoration under non-Gaussian noise. The two main kinds of noise studied in this PhD project are the impulse noise and the Cauchy noise. Impulse noise is due to for instance the malfunctioning pixel elements in the camera sensors, errors...

  16. Noise sensitivity, rather than noise level, predicts the non-auditory effects of noise in community samples: a population-based survey

    Directory of Open Access Journals (Sweden)

    Jangho Park

    2017-04-01

    Full Text Available Abstract Background Excessive noise affects human health and interferes with daily activities. Although environmental noise may not directly cause mental illness, it may accelerate and intensify the development of latent mental disorders. Noise sensitivity (NS is considered a moderator of non-auditory noise effects. In the present study, we aimed to assess whether NS is associated with non-auditory effects. Methods We recruited a community sample of 1836 residents residing in Ulsan and Seoul, South Korea. From July to November 2015, participants were interviewed regarding their demographic characteristics, socioeconomic status, medical history, and NS. The non-auditory effects of noise were assessed using the Center of Epidemiologic Studies Depression, Insomnia Severity index, State Trait Anxiety Inventory state subscale, and Stress Response Inventory-Modified Form. Individual noise levels were recorded from noise maps. A three-model multivariate logistic regression analysis was performed to identify factors that might affect psychiatric illnesses. Results Participants ranged in age from 19 to 91 years (mean: 47.0 ± 16.1 years, and 37.9% (n = 696 were male. Participants with high NS were more likely to have been diagnosed with diabetes and hyperlipidemia and to use psychiatric medication. The multivariable analysis indicated that even after adjusting for noise-related variables, sociodemographic factors, medical illness, and duration of residence, subjects in the high NS group were more than 2 times more likely to experience depression and insomnia and 1.9 times more likely to have anxiety, compared with those in the low NS group. Noise exposure level was not identified as an explanatory value. Conclusions NS increases the susceptibility and hence moderates there actions of individuals to noise. NS, rather than noise itself, is associated with an elevated susceptibility to non-auditory effects.

  17. I cristalli sonici come barriere antirumore - Sonic crystals as tunable noise barriers

    Directory of Open Access Journals (Sweden)

    Federica Morandi

    2017-02-01

    Full Text Available Il presente contributo riporta un'introduzione al tema della propagazione del suono nei cristalli sonici e un excursus sulla letteratura scientifica più recente. Si discutono i risultati di alcune indagini sperimentali condotte presso l’Università di Bologna inerenti misure di Insertion Loss, misure effettuate all’interno del reticolo e misure di intensimetria. Infine i valori di Sound Insulation misurati per un cristallo sonico sono confrontati con valori misurati su barriere tradizionali, evidenziando come il cristallo sonico permetta di raggiungere un isolamento confrontabile con il valore soglia di Insertion Loss raggiungibile a causa della diffrazione del bordo superiore della barriera. ------ This work reports an introduction to the topic of wave propagation in sonic crystals and a review of the recent scientific literature. The paper presents the results of some experimental investigations carried out at the University of Bologna by discussing Insertion Loss measurements, measurements performed inside the lattice and sound intensity measurements. Finally, the Sound Insulation Index measured for a sonic crystal is compared to the values measured for common noise barriers, pointing out that sonic crystals reach insulation values comparable to the maximum Insertion Loss achievable due to the top edge diffraction.

  18. Enhanced Thermionic Emission and Low 1/f Noise in Exfoliated Graphene/GaN Schottky Barrier Diode.

    Science.gov (United States)

    Kumar, Ashutosh; Kashid, Ranjit; Ghosh, Arindam; Kumar, Vikram; Singh, Rajendra

    2016-03-01

    Temperature-dependent electrical transport characteristics of exfoliated graphene/GaN Schottky diodes are investigated and compared with conventional Ni/GaN Schottky diodes. The ideality factor of graphene/GaN and Ni/GaN diodes are measured to be 1.33 and 1.51, respectively, which is suggestive of comparatively higher thermionic emission current in graphene/GaN diode. The barrier height values for graphene/GaN diode obtained using thermionic emission model and Richardson plots are found to be 0.60 and 0.72 eV, respectively, which are higher than predicted barrier height ∼0.40 eV as per the Schottky-Mott model. The higher barrier height is attributed to hole doping of graphene due to graphene-Au interaction which shifts the Fermi level in graphene by ∼0.3 eV. The magnitude of flicker noise of graphene/GaN Schottky diode increases up to 175 K followed by its decrease at higher temperatures. This indicates that diffusion currents and barrier inhomogeneities dominate the electronic transport at lower and higher temperatures, respectively. The exfoliated graphene/GaN diode is found to have lower level of barrier inhomogeneities than conventional Ni/GaN diode, as well as earlier reported graphene/GaN diode fabricated using chemical vapor deposited graphene. The lesser barrier inhomogeneities in graphene/GaN diode results in lower flicker noise by 2 orders of magnitude as compared to Ni/GaN diode. Enhanced thermionic emission current, lower level of inhomogeneities, and reduced flicker noise suggests that graphene-GaN Schottky diodes may have the underlying trend for replacing metal-GaN Schottky diodes.

  19. A Health-Based Metric for Evaluating the Effectiveness of Noise Barrier Mitigation Associated With Transport Infrastructure Noise

    Directory of Open Access Journals (Sweden)

    Geoffrey P Prendergast

    2017-01-01

    Full Text Available Introduction: This study examines the use of the number of night-time sleep disturbances as a health-based metric to assess the cost effectiveness of rail noise mitigation strategies for situations, wherein high-intensity noises dominate such as freight train pass-bys and wheel squeal. Materials and Methods: Twenty residential properties adjacent to the existing and proposed rail tracks in a noise catchment area of the Epping to Thornleigh Third Track project were used as a case study. Awakening probabilities were calculated for individual’s awakening 1, 3 and 5 times a night when subjected to 10 independent freight train pass-by noise events using internal maximum sound pressure levels (LAFmax. Results: Awakenings were predicted using a random intercept multivariate logistic regression model. With source mitigation in place, the majority of the residents were still predicted to be awoken at least once per night (median 88.0%, although substantial reductions in the median probabilities of awakening three and five times per night from 50.9 to 29.4% and 9.2 to 2.7%, respectively, were predicted. This resulted in a cost-effective estimate of 7.6–8.8 less people being awoken at least three times per night per A$1 million spent on noise barriers. Conclusion: The study demonstrates that an easily understood metric can be readily used to assist making decisions related to noise mitigation for large-scale transport projects.

  20. The solar noise barrier project : 2. The effect of street art on performance of a large scale luminescent solar concentrator prototype

    NARCIS (Netherlands)

    Debije, M.G.; Tzikas, C.; Rajkumar, V.A.; de Jong, M.

    2017-01-01

    Noise barriers have been used worldwide to reduce the impact of sound generated from traffic on nearby areas. A common feature to appear on these noise barriers are all manner of graffiti and street art. In this work we describe the relative performance of a large area luminescent solar concentrator

  1. Use of co-combustion bottom ash to design an acoustic absorbing material for highway noise barriers

    International Nuclear Information System (INIS)

    Arenas, Celia; Leiva, Carlos; Vilches, Luis F.; Cifuentes, Héctor

    2013-01-01

    Highlights: • The particle size of bottom ash influenced the acoustic behavior of the barrier. • The best sound absorption coefficients were measured for larger particle sizes. • The maximum noise absorption is displaced to lower frequencies for higher thickness. • A noise barrier was designed with better properties than commercial products. • Recycling products from bottom ash no present leaching and radioactivity problems. - Abstract: The present study aims to determine and evaluate the applicability of a new product consisting of coal bottom ash mixed with Portland cement in the application of highway noise barriers. In order to effectively recycle the bottom ash, the influence of the grain particle size of bottom ash, the thickness of the panel and the combination of different layers with various particle sizes have been studied, as well as some environmental properties including leachability (EN-12457-4, NEN-7345) and radioactivity tests. Based on the obtained results, the acoustic properties of the final composite material were similar or even better than those found in porous concrete used for the same application. According to this study, the material produced presented no environmental risk

  2. Use of co-combustion bottom ash to design an acoustic absorbing material for highway noise barriers

    Energy Technology Data Exchange (ETDEWEB)

    Arenas, Celia; Leiva, Carlos; Vilches, Luis F. [University of Seville, School of Industrial Engineering, Department of Chemical and Environmental Engineering, Camino de los Descubrimientos s/n, E-41092 Seville (Spain); Cifuentes, Héctor, E-mail: bulte@us.es [University of Seville, School of Industrial Engineering, Continuum Mechanics and Structural Analysis Department, Camino de los Descubrimientos s/n, E-41092 Seville (Spain)

    2013-11-15

    Highlights: • The particle size of bottom ash influenced the acoustic behavior of the barrier. • The best sound absorption coefficients were measured for larger particle sizes. • The maximum noise absorption is displaced to lower frequencies for higher thickness. • A noise barrier was designed with better properties than commercial products. • Recycling products from bottom ash no present leaching and radioactivity problems. - Abstract: The present study aims to determine and evaluate the applicability of a new product consisting of coal bottom ash mixed with Portland cement in the application of highway noise barriers. In order to effectively recycle the bottom ash, the influence of the grain particle size of bottom ash, the thickness of the panel and the combination of different layers with various particle sizes have been studied, as well as some environmental properties including leachability (EN-12457-4, NEN-7345) and radioactivity tests. Based on the obtained results, the acoustic properties of the final composite material were similar or even better than those found in porous concrete used for the same application. According to this study, the material produced presented no environmental risk.

  3. Evaluation of the potential of PV noise barrier technology for electricity production and market share. Final report

    International Nuclear Information System (INIS)

    Goetzberger, A.; Kleiss, G.; Castello, S.; Hille, G.; Reise, C.; Wiemken, E.; Betcke, J.W.H.; Van Dijk, V.A.P.; Pearsall, N.; Hynes, K.; Gaidddon, B.; Nordmann, T.; Froelich, A.

    1999-06-01

    The analysis of existing and planned noise barriers along rails and roads has been carried out by the national partners together with national authorities, which are experts and responsible for the required data. The methodical approach of this study includes the set-up of a grid along longitude and latitudes with 1 by 1 degrees for Germany, Italy, France, United Kingdom and 0.5 by 0.5 degrees for the Netherlands and Switzerland. For each degree the length and orientation of rails and roads, the existing and planned noise barriers are registered and grouped according to their orientations. The solar radiation is based on data of a METEONORM data set. This includes the solar radiation on horizontal orientation as well as various inclination angles for all possible orientations. Moreover, possible shading has been considered. The technical specifications of noise barriers (PVNB) are based on the comprehensive knowledge of TNC GmbH and TNC AG with various plants realised. Technologies have been considered for both state-of-the-art and innovative concepts such as bifacial PVNB. In bifacial PVNB the PV-module is mounted vertically on both sides and is used at the same time as noise reflecting material. Installed PV power and produced electricity have been calculated for: 1. theoretical potential 2. technical potential 3. short-term resp. European extrapolated potential 4. anticipated potential 5. EU-member assessment The result of this study confirms the current activities to implement PV on noise barriers as an important share in the PV market.The report is subdivided into two volumes: Volume 1 contains the main topics and results, and Volume 2 contains additional information on the solar radiation, typical concepts as an excerpt of the various potentials and all country maps with the required explanations. 95 refs

  4. Occupational Hearing Loss from Non-Gaussian Noise.

    Science.gov (United States)

    Suter, Alice H

    2017-08-01

    Noise levels are truly continuous in relatively few occupations, with some degree of intermittency the most common condition. The sound levels of intermittent noise are often referred to as non-Gaussian in that they are not normally distributed in the time domain. In some conditions, intermittent noise affects the ear differently from continuous noise, and it is this assumption that underlies the selection of the 5-dB exchange rate (ER). The scientific and professional communities have debated this assumption over recent decades. This monograph explores the effect of non-Gaussian noise on the auditory system. It begins by summarizing an earlier report by the same author concentrating on the subject of the ER. The conclusions of the earlier report supported the more conservative 3-dB ER with possible adjustments to the permissible exposure limit for certain working conditions. The current document has expanded on the earlier report in light of the relevant research accomplished in the intervening decades. Although some of the animal research has supported the mitigating effect of intermittency, a closer look at many of these studies reveals certain weaknesses, along with the fact that these noise exposures were not usually representative of the conditions under which people actually work. The more recent animal research on complex noise shows that intermittencies do not protect the cochlea and that many of the previous assumptions about the ameliorative effect of intermittencies are no longer valid, lending further support to the 3-dB ER. The neurologic effects of noise on hearing have gained increasing attention in recent years because of improvements in microscopy and immunostaining techniques. Animal experiments showing damage to auditory synapses from noise exposures previously considered harmless may signify the need for a more conservative approach to the assessment of noise-induced hearing loss and consequently the practice of hearing conservation programs.

  5. Wind Noise Reduction using Non-negative Sparse Coding

    DEFF Research Database (Denmark)

    Schmidt, Mikkel N.; Larsen, Jan; Hsiao, Fu-Tien

    2007-01-01

    We introduce a new speaker independent method for reducing wind noise in single-channel recordings of noisy speech. The method is based on non-negative sparse coding and relies on a wind noise dictionary which is estimated from an isolated noise recording. We estimate the parameters of the model ...... and discuss their sensitivity. We then compare the algorithm with the classical spectral subtraction method and the Qualcomm-ICSI-OGI noise reduction method. We optimize the sound quality in terms of signal-to-noise ratio and provide results on a noisy speech recognition task....

  6. Holistic optimization of noise barriers from acoustical and non-acoustical parameters

    NARCIS (Netherlands)

    Defrance, J.; Leissing, T.; Grannec, F.; Jean, P.; Lutgendorf, D.; Heinkele, C.; Clairbois, J.P.

    2012-01-01

    We present the last results obtained within WP5 "Holistic optimizations" of the QUIESST European Project dedicated to the assessment of Noise Reducing Devices' acoustical performances. A first task was a state of the art of existing methods followed by choices of best solutions for holistic

  7. Comparison between old and new noise standards in Nagoya City

    Science.gov (United States)

    Asai, Atsushi; Mishina, Yoshiaki; Oishi, Yasaki; Ogura, Toshimitsu; Hayashi, Akinori; Omiya, Masaaki; Kuno, Kazuhiro

    2004-10-01

    The Japanese Environmental Agency (now the Ministry of the Environment) updated the environmental quality standards for noise in April 1999. The new standards replaced the median value of percentile level L50 for noise evaluation with the equivalent sound pressure level LAeq. The standards renewed the classification of areas and time sections. The most significant change was the introduction of category of artery-road-adjacent area. This report sets the range of the artery-road-adjacent area to 20 m or less from the applicable road to compare the new standards with the old, based on data collected in Nagoya City. The achieved rates for the new standards seem to be on the whole the same as those for the old standards. However, a detailed analysis reveals some differences, such as higher achieved rates in the artery-road-adjacent areas and lower achieved rates in the general areas for the new standards than for the old.

  8. Assessment of noise pollution in and around a sensitive zone in North India and its non-auditory impacts.

    Science.gov (United States)

    Khaiwal, Ravindra; Singh, Tanbir; Tripathy, Jaya Prasad; Mor, Suman; Munjal, Sanjay; Patro, Binod; Panda, Naresh

    2016-10-01

    Noise pollution in hospitals is recognized as a serious health hazard. Considering this, the current study aimed to map the noise pollution levels and to explore the self reported non-auditory effects of noise in a tertiary medical institute. The study was conducted in an 1800-bedded tertiary hospital where 27 sites (outdoor, indoor, road side and residential areas) were monitored for exposure to noise using Sound Level Meter for 24h. A detailed noise survey was also conducted around the sampling sites using a structured questionnaire to understand the opinion of the public regarding the impact of noise on their daily lives. The equivalent sound pressure level (Leq) was found higher than the permissible limits at all the sites both during daytime and night. The maximum equivalent sound pressure level (Lmax) during the day was observed higher (>80dB) at the emergency and around the main entrance of the hospital campus. Almost all the respondents (97%) regarded traffic as the major source of noise. About three-fourths (74%) reported irritation with loud noise whereas 40% of respondents reported headache due to noise. Less than one-third of respondents (29%) reported loss of sleep due to noise and 8% reported hypertension, which could be related to the disturbance caused due to noise. Noise levels in and around the hospital was well above the permissible standards. The recent Global Burden of Disease highlights the increasing risk of non communicable diseases. The non-auditory effects studied in the current work add to the risk factors associated with non communicable diseases. Hence, there is need to address the issue of noise pollution and associated health risks specially for vulnerable population. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  9. Methods to characterize non-Gaussian noise in TAMA

    International Nuclear Information System (INIS)

    Ando, Masaki; Arai, K; Takahashi, R; Tatsumi, D; Beyersdorf, P; Kawamura, S; Miyoki, S; Mio, N; Moriwaki, S; Numata, K; Kanda, N; Aso, Y; Fujimoto, M-K; Tsubono, K; Kuroda, K

    2003-01-01

    We present a data characterization method for the main output signal of the interferometric gravitational-wave detector, in particular targeting at effective detection of burst gravitational waves from stellar core collapse. The time scale of non-Gaussian events is evaluated in this method, and events with longer time scale than real signals are rejected as non-Gaussian noises. As a result of data analysis using 1000 h of real data with the interferometric gravitational-wave detector TAMA300, the false-alarm rate was improved 10 3 times with this non-Gaussian noise evaluation and rejection method

  10. Reduction of Air Pollution Levels Downwind of a Road with an Upwind Noise Barrier

    Science.gov (United States)

    We propose a dispersion model to characterize the impact of an upwind solid noise barrier next to a highway on air pollution concentrations downwind of the road. The model is based on data from wind tunnel experiments conducted by Heist et al. (2009). The model assumes that the...

  11. Feasibility study on the least square method for fitting non-Gaussian noise data

    Science.gov (United States)

    Xu, Wei; Chen, Wen; Liang, Yingjie

    2018-02-01

    This study is to investigate the feasibility of least square method in fitting non-Gaussian noise data. We add different levels of the two typical non-Gaussian noises, Lévy and stretched Gaussian noises, to exact value of the selected functions including linear equations, polynomial and exponential equations, and the maximum absolute and the mean square errors are calculated for the different cases. Lévy and stretched Gaussian distributions have many applications in fractional and fractal calculus. It is observed that the non-Gaussian noises are less accurately fitted than the Gaussian noise, but the stretched Gaussian cases appear to perform better than the Lévy noise cases. It is stressed that the least-squares method is inapplicable to the non-Gaussian noise cases when the noise level is larger than 5%.

  12. Regression of non-linear coupling of noise in LIGO detectors

    Science.gov (United States)

    Da Silva Costa, C. F.; Billman, C.; Effler, A.; Klimenko, S.; Cheng, H.-P.

    2018-03-01

    In 2015, after their upgrade, the advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors started acquiring data. The effort to improve their sensitivity has never stopped since then. The goal to achieve design sensitivity is challenging. Environmental and instrumental noise couple to the detector output with different, linear and non-linear, coupling mechanisms. The noise regression method we use is based on the Wiener–Kolmogorov filter, which uses witness channels to make noise predictions. We present here how this method helped to determine complex non-linear noise couplings in the output mode cleaner and in the mirror suspension system of the LIGO detector.

  13. Transportation Energy Futures Series: Non-Cost Barriers to Consumer Adoption of New Light-Duty Vehicle Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, T.

    2013-03-01

    Consumer preferences are key to the adoption of new vehicle technologies. Barriers to consumer adoption include price and other obstacles, such as limited driving range and charging infrastructure; unfamiliarity with the technology and uncertainty about direct benefits; limited makes and models with the technology; reputation or perception of the technology; standardization issues; and regulations. For each of these non-cost barriers, this report estimates an effective cost and summarizes underlying influences on consumer preferences, approximate magnitude and relative severity, and assesses potential actions, based on a comprehensive literature review. While the report concludes that non-cost barriers are significant, effective cost and potential market share are very uncertain. Policies and programs including opportunities for drivers to test drive advanced vehicles, general public outreach and information programs, incentives for providing charging and fueling infrastructure, and development of technology standards were examined for their ability to address barriers, but little quantitative data exists on the effectiveness of these measures. This is one in a series of reports produced as a result of the Transportation Energy Futures project, a Department of Energy-sponsored multi-agency effort to pinpoint underexplored strategies for reducing GHGs and petroleum dependence related to transportation.

  14. Acceptable noise level with Danish, Swedish, and non-semantic speech materials

    DEFF Research Database (Denmark)

    Brännström, K Jonas; Lantz, Johannes; Nielsen, Lars Holme

    2012-01-01

    reported results from American studies. Generally, significant differences were seen between test conditions using different types of noise within ears in each population. Significant differences were seen for ANL across populations, also when the non-semantic ISTS was used as speech signal. Conclusions......Abstract Objective: Acceptable noise level (ANL) has been established as a method to quantify the acceptance of background noise while listening to speech presented at the most comfortable level. The aim of the present study was to generate Danish, Swedish, and a non-semantic version of the ANL...... test and investigate normal-hearing Danish and Swedish subjects' performance on these tests. Design: ANL was measured using Danish and Swedish running speech with two different noises: Speech-weighted amplitude-modulated noise, and multitalker speech babble. ANL was also measured using the non...

  15. Maximum Correntropy Criterion Kalman Filter for α-Jerk Tracking Model with Non-Gaussian Noise

    Directory of Open Access Journals (Sweden)

    Bowen Hou

    2017-11-01

    Full Text Available As one of the most critical issues for target track, α -jerk model is an effective maneuver target track model. Non-Gaussian noises always exist in the track process, which usually lead to inconsistency and divergence of the track filter. A novel Kalman filter is derived and applied on α -jerk tracking model to handle non-Gaussian noise. The weighted least square solution is presented and the standard Kalman filter is deduced firstly. A novel Kalman filter with the weighted least square based on the maximum correntropy criterion is deduced. The robustness of the maximum correntropy criterion is also analyzed with the influence function and compared with the Huber-based filter, and, moreover, the kernel size of Gaussian kernel plays an important role in the filter algorithm. A new adaptive kernel method is proposed in this paper to adjust the parameter in real time. Finally, simulation results indicate the validity and the efficiency of the proposed filter. The comparison study shows that the proposed filter can significantly reduce the noise influence for α -jerk model.

  16. CONTRIBUTION OF QUADRATIC RESIDUE DIFFUSERS TO EFFICIENCY OF TILTED PROFILE PARALLEL HIGHWAY NOISE BARRIERS

    Directory of Open Access Journals (Sweden)

    M. R. Monazzam ، P. Nassiri

    2009-10-01

    Full Text Available This paper presents the results of an investigation on the acoustic performance of tilted profile parallel barriers with quadratic residue diffuser (QRD tops and faces. A 2D boundary element method (BEM is used to predict the barrier insertion loss. The results of rigid and with absorptive coverage are also calculated for comparisons. Using QRD on the top surface and faces of all tilted profile parallel barrier models introduced here is found to improve the efficiency of barriers compared with rigid equivalent parallel barrier at the examined receiver positions. Applying a QRD with frequency design of 400 Hz on 5 degrees tilted parallel barrier improves the overall performance of its equivalent rigid barrier by 1.8 dB(A. Increase in the treated surfaces with reactive elements shifts the effective performance toward lower frequencies. It is found that by tilting the barriers from 0 to 10 degrees in parallel set up, the degradation effects in parallel barriers is reduced but the absorption effect of fibrous materials and also diffusivity of the quadratic residue diffuser is reduced significantly. In this case all the designed barriers have better performance with 10 degrees tilting in parallel set up. The most economic traffic noise parallel barrier which produces significantly high performance, is achieved by covering the top surface of the barrier closed to the receiver by just a QRD with frequency design of 400 Hz and tilting angle of 10 degrees. The average A-weighted insertion loss in this barrier is predicted to be 16.3 dB (A.

  17. Evidence of Non-extensivity in Earth's Ambient Noise

    Science.gov (United States)

    Koutalonis, Ioannis; Vallianatos, Filippos

    2017-12-01

    The study of ambient seismic noise is one of the important scientific and practical research challenges, due to its use in a number of geophysical applications. In this work, we describe Earth's ambient noise fluctuations in terms of non-extensive statistical physics. We found that Earth's ambient noise increments follow the q-Gaussian distribution. This indicates that Earth's ambient noise's fluctuations are not random and present long-term memory effects that could be described in terms of Tsallis entropy. Our results suggest that q values depend on the time length used and that the non-extensive parameter, q, converges to value q → 1 for short-time windows and a saturation value of q ≈ 1.33 for longer ones. The results are discussed from the point of view of superstatistics introduced by Beck [Contin Mech Thermodyn 16(3):293-304, 2004] and connects the q values with the system's degrees of freedom. Our work indicates that the converged (maximum) value is q = 1.33 and is related to 5 degrees of freedom.

  18. Cost-effectiveness of a Ceramide-Infused Skin Barrier Versus a Standard Barrier

    Science.gov (United States)

    Berger, Ariel; Inglese, Gary; Skountrianos, George; Karlsmark, Tonny; Oguz, Mustafa

    2018-01-01

    PURPOSE: To assess the cost-effectiveness of a ceramide-infused skin barrier (CIB) versus other skin barriers (standard of care) among patients who have undergone ostomy creation. DESIGN: Cost-effectiveness analysis, based on a decision-analytic model that was estimated using data from the ADVOCATE (A Study Determining Variances in Ostomy Skin Conditions And The Economic Impact) trial, which investigated stoma-related healthcare costs over 12 weeks among patients who recently underwent fecal ostomy, and from other sources. SUBJECTS AND SETTING: Analysis was based on a hypothetical cohort of 1000 patients who recently underwent fecal ostomy; over a 1-year period, 500 patients were assumed to use CIB and 500 were assumed to use standard of care. METHODS: We adapted a previous economic model to estimate expected 1-year costs and outcomes among persons with a new ostomy assumed to use CIB versus standard of care. Outcomes of interest included peristomal skin complications (PSCs) (up to 2 during the 1-year period of interest) and quality-adjusted life days (QALDs); QALDs vary from 1, indicating a day of perfect health to 0, indicating a day with the lowest possible health (deceased). Subjects were assigned QALDs on a daily basis, with the value of the QALD on any given day based on whether the patient was experiencing a PSC. Costs included those related to skin barriers, ostomy accessories, and care of PSCs. The incremental cost-effectiveness of CIB versus standard of care was estimated as the incremental cost per PSC averted and QALD gained, respectively; net monetary benefit of CIB was also estimated. All analyses were run using the perspective of an Australian payer. RESULTS: On a per-patient basis, use of CIB was expected over a 1-year period to result in 0.16 fewer PSCs, an additional 0.35 QALDs, and a savings of A$180 (Australian dollars, US $137) in healthcare costs all versus standard of care. Management with CIB provided a net monetary benefit (calculated as

  19. Detrending of non-stationary noise data by spline techniques

    International Nuclear Information System (INIS)

    Behringer, K.

    1989-11-01

    An off-line method for detrending non-stationary noise data has been investigated. It uses a least squares spline approximation of the noise data with equally spaced breakpoints. Subtraction of the spline approximation from the noise signal at each data point gives a residual noise signal. The method acts as a high-pass filter with very sharp frequency cutoff. The cutoff frequency is determined by the breakpoint distance. The steepness of the cutoff is controlled by the spline order. (author) 12 figs., 1 tab., 5 refs

  20. Non-linearity consideration when analyzing reactor noise statistical characteristics. [BWR

    Energy Technology Data Exchange (ETDEWEB)

    Kebadze, B V; Adamovski, L A

    1975-06-01

    Statistical characteristics of boiling water reactor noise in the vicinity of stability threshold are studied. The reactor is considered as a non-linear system affected by random perturbations. To solve a non-linear problem the principle of statistical linearization is used. It is shown that the halfwidth of resonance peak in neutron power noise spectrum density as well as the reciprocal of noise dispersion, which are used in predicting a stable operation theshold, are different from zero both within and beyond the stability boundary the determination of which was based on linear criteria.

  1. Contribution of diffuser surfaces to efficiency of tilted T shape parallel highway noise barriers

    Directory of Open Access Journals (Sweden)

    N. Javid Rouzi

    2009-04-01

    Full Text Available Background and aimsThe paper presents the results of an investigation on the acoustic  performance of tilted profile parallel barriers with quadratic residue diffuser tops and faces.MethodsA2D boundary element method (BEM is used to predict the barrier insertion loss. The results of rigid and with absorptive coverage are also calculated for comparisons. Using QRD on the top surface and faces of all tilted profile parallel barrier models introduced here is found to  improve the efficiency of barriers compared with rigid equivalent parallel barrier at the examined  receiver positions.Results Applying a QRD with frequency design of 400 Hz on 5 degrees tilted parallel barrier  improves the overall performance of its equivalent rigid barrier by 1.8 dB(A. Increase the treated surfaces with reactive elements shifts the effective performance toward lower frequencies. It is  found that by tilting the barriers from 0 to 10 degrees in parallel set up, the degradation effects in  parallel barriers is reduced but the absorption effect of fibrous materials and also diffusivity of thequadratic residue diffuser is reduced significantly. In this case all the designed barriers have better  performance with 10 degrees tilting in parallel set up.ConclusionThe most economic traffic noise parallel barrier, which produces significantly  high performance, is achieved by covering the top surface of the barrier closed to the receiver by  just a QRD with frequency design of 400 Hz and tilting angle of 10 degrees. The average Aweighted  insertion loss in this barrier is predicted to be 16.3 dB (A.

  2. Transportation Energy Futures Series. Non-Cost Barriers to Consumer Adoption of New Light-Duty Vehicle Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, Thomas [Argonne National Lab. (ANL), Argonne, IL (United States)

    2013-03-01

    Consumer preferences are key to the adoption of new vehicle technologies. Barriers to consumer adoption include price and other obstacles, such as limited driving range and charging infrastructure; unfamiliarity with the technology and uncertainty about direct benefits; limited makes and models with the technology; reputation or perception of the technology; standardization issues; and regulations. For each of these non-cost barriers, this report estimates an effective cost and summarizes underlying influences on consumer preferences, approximate magnitude and relative severity, and assesses potential actions, based on a comprehensive literature review. While the report concludes that non-cost barriers are significant, effective cost and potential market share are very uncertain. Policies and programs including opportunities for drivers to test drive advanced vehicles, general public outreach and information programs, incentives for providing charging and fueling infrastructure, and development of technology standards were examined for their ability to address barriers, but little quantitative data exists on the effectiveness of these measures. This is one in a series of reports produced as a result of the Transportation Energy Futures project, a Department of Energy-sponsored multi-agency effort to pinpoint underexplored strategies for reducing GHGs and petroleum dependence related to transportation. View all reports on the TEF Web page, http://www.eere.energy.gov/analysis/transportationenergyfutures/index.html.

  3. On the effects of emission standards as a non-tariff barrier to trade in the case of a foreign Bertrand duopoly: A note

    International Nuclear Information System (INIS)

    Toshimitsu, Tsuyoshi

    2008-01-01

    Employing a model of an environmentally differentiated product market, we analyze how an emission regulation as non-tariff barriers to trade affects imports, the environment, and welfare in the case of a foreign Bertrand duopoly. Related to this issue, we reconsider the result of Moraga-Gonzalez and Padron-Fumero [Moraga-Gonzalez, J.L., Padron-Fumero, N., 2002. Environmental policy in a green market. Environmental and Resource Economics 22, 419-447] that a strict emission standard on a dirtier product degrades the environment and reduces the net social surplus associated with the valuation of environmental damage, if the marginal social valuation of environmental damage is larger. On the other hand, we show that a strict emission standard on a cleaner product always improves the environment and the net social surplus associated with the valuation of environmental damage. (author)

  4. Traffic noise control of a city

    International Nuclear Information System (INIS)

    Ahmed, A.; Khan, J.A.; Lakhani, A.H.; Hyder, F.G.; Shamsuddin, S.A.

    2003-01-01

    Long exposure to noise due to traffic affects our health and comfort. A noise level up to 45 dB is acceptable for the buildings in the city. A traffic noise study was conducted in Karachi at places of high traffic flow. The noise level was between 75-85 dB. Residential and commercial buildings had sound level up to 79 dB. Reducing vehicle noise by using proper muffler and acoustic treatment should first control traffic noise. Then noise can be reduced by 10-15 dB by constructing barriers of wood or concrete along roadside. Barrier height for sound attenuation can be found from Fresnel Number. The barrier reduces noise better if width at the top is increased and an inward bend of 60 degree is placed at the top. Where feasible a 4-5 meter high concrete barrier is recommended otherwise the nearby buildings from the road should be insulated and acoustically treated. (author)

  5. External non-white noise and nonequilibrium phase transitions

    International Nuclear Information System (INIS)

    Sancho, J.M.; San Miguel, M.

    1980-01-01

    Langevin equations with external non-white noise are considered. A Fokker Planck equation valid in general in first order of the correlation time tau of the noise is derived. In some cases its validity can be extended to any value of tau. The effect of a finite tau in the nonequilibrium phase transitions induced by the noise is analyzed, by means of such Fokker Planck equation, in general, for the Verhulst equation under two different kind of fluctuations, and for a genetic model. It is shown that new transitions can appear and that the threshold value of the parameter can be changed. (orig.)

  6. Robust statistics for deterministic and stochastic gravitational waves in non-Gaussian noise. II. Bayesian analyses

    International Nuclear Information System (INIS)

    Allen, Bruce; Creighton, Jolien D.E.; Flanagan, Eanna E.; Romano, Joseph D.

    2003-01-01

    In a previous paper (paper I), we derived a set of near-optimal signal detection techniques for gravitational wave detectors whose noise probability distributions contain non-Gaussian tails. The methods modify standard methods by truncating or clipping sample values which lie in those non-Gaussian tails. The methods were derived, in the frequentist framework, by minimizing false alarm probabilities at fixed false detection probability in the limit of weak signals. For stochastic signals, the resulting statistic consisted of a sum of an autocorrelation term and a cross-correlation term; it was necessary to discard 'by hand' the autocorrelation term in order to arrive at the correct, generalized cross-correlation statistic. In the present paper, we present an alternative derivation of the same signal detection techniques from within the Bayesian framework. We compute, for both deterministic and stochastic signals, the probability that a signal is present in the data, in the limit where the signal-to-noise ratio squared per frequency bin is small, where the signal is nevertheless strong enough to be detected (integrated signal-to-noise ratio large compared to 1), and where the total probability in the non-Gaussian tail part of the noise distribution is small. We show that, for each model considered, the resulting probability is to a good approximation a monotonic function of the detection statistic derived in paper I. Moreover, for stochastic signals, the new Bayesian derivation automatically eliminates the problematic autocorrelation term

  7. Random noise suppression of seismic data using non-local Bayes algorithm

    Science.gov (United States)

    Chang, De-Kuan; Yang, Wu-Yang; Wang, Yi-Hui; Yang, Qing; Wei, Xin-Jian; Feng, Xiao-Ying

    2018-02-01

    For random noise suppression of seismic data, we present a non-local Bayes (NL-Bayes) filtering algorithm. The NL-Bayes algorithm uses the Gaussian model instead of the weighted average of all similar patches in the NL-means algorithm to reduce the fuzzy of structural details, thereby improving the denoising performance. In the denoising process of seismic data, the size and the number of patches in the Gaussian model are adaptively calculated according to the standard deviation of noise. The NL-Bayes algorithm requires two iterations to complete seismic data denoising, but the second iteration makes use of denoised seismic data from the first iteration to calculate the better mean and covariance of the patch Gaussian model for improving the similarity of patches and achieving the purpose of denoising. Tests with synthetic and real data sets demonstrate that the NL-Bayes algorithm can effectively improve the SNR and preserve the fidelity of seismic data.

  8. Delay-enhanced stability and stochastic resonance in perception bistability under non-Gaussian noise

    International Nuclear Information System (INIS)

    Yang, Tao; Zeng, Chunhua; Liu, Ruifen; Wang, Hua; Mei, Dongcheng

    2015-01-01

    In this paper we investigate the effect of time delay in an attractor network model of perception bistability driven by non-Gaussian noise. Using delay Langevin and Fokker–Planck approaches, the theoretical analysis of the model is presented. It is found that the mean first-passage time (MFPT) as a function of the time delay exhibits a maximum, which is identified as the characteristic of the delay-enhanced stability of the system. This is different to the case of noise-enhanced stability. The non-Gaussian noise-enhanced stability of the system is also analyzed. The signal-to-noise ratio (SNR) as a function of the noise intensity exhibits a maximum. This maximum implies the identifying characteristic of stochastic resonance (SR), and the time delay and non-Gaussian noise can enhance the SR phenomenon. (paper)

  9. Low frequency noise in asymmetric double barrier magnetic tunnel junctions with a top thin MgO layer

    International Nuclear Information System (INIS)

    Guo Hui-Qiang; Tang Wei-Yue; Liu Liang; Wei Jian; Li Da-Lai; Feng Jia-Feng; Han Xiu-Feng

    2015-01-01

    Low frequency noise has been investigated at room temperature for asymmetric double barrier magnetic tunnel junctions (DBMTJs), where the coupling between the top and middle CoFeB layers is antiferromagnetic with a 0.8-nm thin top MgO barrier of the CoFeB/MgO/CoFe/CoFeB/MgO/CoFeB DBMTJ. At enough large bias, 1/f noise dominates the voltage noise power spectra in the low frequency region, and is conventionally characterized by the Hooge parameter α mag . With increasing external field, the top and bottom ferromagnetic layers are aligned by the field, and then the middle free layer rotates from antiparallel state (antiferromagnetic coupling between top and middle ferromagnetic layers) to parallel state. In this rotation process α mag and magnetoresistance-sensitivity-product show a linear dependence, consistent with the fluctuation dissipation relation. With the magnetic field applied at different angles (θ) to the easy axis of the free layer, the linear dependence persists while the intercept of the linear fit satisfies a cos(θ) dependence, similar to that for the magnetoresistance, suggesting intrinsic relation between magnetic losses and magnetoresistance. (rapid communication)

  10. Noise and non-linearities in high-throughput data

    International Nuclear Information System (INIS)

    Nguyen, Viet-Anh; Lió, Pietro; Koukolíková-Nicola, Zdena; Bagnoli, Franco

    2009-01-01

    High-throughput data analyses are becoming common in biology, communications, economics and sociology. The vast amounts of data are usually represented in the form of matrices and can be considered as knowledge networks. Spectra-based approaches have proved useful in extracting hidden information within such networks and for estimating missing data, but these methods are based essentially on linear assumptions. The physical models of matching, when applicable, often suggest non-linear mechanisms, that may sometimes be identified as noise. The use of non-linear models in data analysis, however, may require the introduction of many parameters, which lowers the statistical weight of the model. According to the quality of data, a simpler linear analysis may be more convenient than more complex approaches. In this paper, we show how a simple non-parametric Bayesian model may be used to explore the role of non-linearities and noise in synthetic and experimental data sets

  11. STAMINA - Model description. Standard Model Instrumentation for Noise Assessments

    NARCIS (Netherlands)

    Schreurs EM; Jabben J; Verheijen ENG; CMM; mev

    2010-01-01

    Deze rapportage beschrijft het STAMINA-model, dat staat voor Standard Model Instrumentation for Noise Assessments en door het RIVM is ontwikkeld. Het instituut gebruikt dit standaardmodel om omgevingsgeluid in Nederland in kaart te brengen. Het model is gebaseerd op de Standaard Karteringsmethode

  12. Colored non-gaussian noise driven open systems: generalization of Kramers' theory with a unified approach.

    Science.gov (United States)

    Baura, Alendu; Sen, Monoj Kumar; Goswami, Gurupada; Bag, Bidhan Chandra

    2011-01-28

    In this paper we have calculated escape rate from a meta stable state in the presence of both colored internal thermal and external nonthermal noises. For the internal noise we have considered usual gaussian distribution but the external noise may be gaussian or non-gaussian in characteristic. The calculated rate is valid for low noise strength of non-gaussian noise such that an effective gaussian approximation of non-gaussian noise wherein the higher order even cumulants of order "4" and higher are neglected. The rate expression we derived here reduces to the known results of the literature, as well as for purely external noise driven activated rate process. The latter exhibits how the rate changes if one switches from non-gaussian to gaussian character of the external noise.

  13. Activation barrier scaling and crossover for noise-induced switching in micromechanical parametric oscillators.

    Science.gov (United States)

    Chan, H B; Stambaugh, C

    2007-08-10

    We explore fluctuation-induced switching in parametrically driven micromechanical torsional oscillators. The oscillators possess one, two, or three stable attractors depending on the modulation frequency. Noise induces transitions between the coexisting attractors. Near the bifurcation points, the activation barriers are found to have a power law dependence on frequency detuning with critical exponents that are in agreement with predicted universal scaling relationships. At large detuning, we observe a crossover to a different power law dependence with an exponent that is device specific.

  14. Considerations in the development of subsurface containment barrier performance standards

    International Nuclear Information System (INIS)

    Dunstan, S.; Zdinak, A.P.; Lodman, D.

    1997-01-01

    The U.S. Department of Energy (DOE) is supporting subsurface barriers as an alternative remedial option for management of contamination problems at their facilities. Past cleanup initiatives have sometimes proven ineffective or extremely expensive. Economic considerations coupled with changing public and regulatory philosophies regarding remediation techniques makes subsurface barriers a promising technology for future cleanup efforts. As part of the initiative to develop subsurface containment barriers as an alternative remedial option, DOE funded MSE Technology Applications, Inc. (MSE) to conduct a comprehensive review to identify performance considerations for the acceptability of subsurface barrier technologies as a containment method. Findings from this evaluation were intended to provide a basis for selection and application of containment technologies to address waste problems at DOE sites. Based on this study, the development of performance standards should consider: (1) sustainable low hydraulic conductivity; (2) capability to meet applicable regulations; (3) compatibility with subsurface environmental conditions; (4) durability and long-term stability; (5) repairability; and (6) verification and monitoring. This paper describes the approach for determining considerations for performance standards

  15. Estimating the Economic Effects of Reducing Non-Tariff Barriers in the EEU

    OpenAIRE

    Vinokurov, Evgeny; Demidenko, Mikhail; Pelipas, Igor; Tochitskaya, Irina; Shymanovich, Gleb; Lipin, Andrey; Movchan, Veronika

    2015-01-01

    The report provides the first comprehensive assessment of the effects of non-tariff barriers on mutual trade in the EEU and gives recommendations as to how to remove them. It is based on a poll of 530 Russian, Kazakh and Belarusian exporters. In the research non-tariff barriers are divided into two groups. The first group includes non-tariff barriers such as sanitary and phytosanitary measures, technical barriers to trade, quotas, prohibitions, and quantitative controls. The second group comp...

  16. Making tensor factorizations robust to non-gaussian noise.

    Energy Technology Data Exchange (ETDEWEB)

    Chi, Eric C. (Rice University, Houston, TX); Kolda, Tamara Gibson

    2011-03-01

    Tensors are multi-way arrays, and the CANDECOMP/PARAFAC (CP) tensor factorization has found application in many different domains. The CP model is typically fit using a least squares objective function, which is a maximum likelihood estimate under the assumption of independent and identically distributed (i.i.d.) Gaussian noise. We demonstrate that this loss function can be highly sensitive to non-Gaussian noise. Therefore, we propose a loss function based on the 1-norm because it can accommodate both Gaussian and grossly non-Gaussian perturbations. We also present an alternating majorization-minimization (MM) algorithm for fitting a CP model using our proposed loss function (CPAL1) and compare its performance to the workhorse algorithm for fitting CP models, CP alternating least squares (CPALS).

  17. Toward the detection of gravitational waves under non-Gaussian noises II. Independent component analysis.

    Science.gov (United States)

    Morisaki, Soichiro; Yokoyama, Jun'ichi; Eda, Kazunari; Itoh, Yousuke

    2016-01-01

    We introduce a new analysis method to deal with stationary non-Gaussian noises in gravitational wave detectors in terms of the independent component analysis. First, we consider the simplest case where the detector outputs are linear combinations of the inputs, consisting of signals and various noises, and show that this method may be helpful to increase the signal-to-noise ratio. Next, we take into account the time delay between the inputs and the outputs. Finally, we extend our method to nonlinearly correlated noises and show that our method can identify the coupling coefficients and remove non-Gaussian noises. Although we focus on gravitational wave data analysis, our methods are applicable to the detection of any signals under non-Gaussian noises.

  18. Impact of the 'non-destructive' multiple-readout on the Lorentzian noise

    International Nuclear Information System (INIS)

    Guazzoni, C.; Gatti, E.; Geraci, A.

    2006-01-01

    In this paper, we discuss the effect of 'non-destructive' multiple-readout on the Lorentzian noise. To our knowledge, it is the first time that such interaction is investigated. We have studied the peculiarities of the shape of the optimum weighting function for the multiple-readout technique in the presence of Lorentzian noise and other noise sources. The impact of the Lorentzian noise on the resolution achievable with the multiple-readout technique is analyzed in detail with respect to the interaction between the oscillation time and the characteristic time constant of the Lorentzian noise

  19. Assessment of reflectivity of noise barriers in the far field – QUIESST method compared to traditional approach

    NARCIS (Netherlands)

    Roo, F. de

    2013-01-01

    The sound reflectivity of noise barriers elements is one of the major acoustic product characteristics. Traditionally this property was tested in reverberation rooms according to EN 1793-1 and the results were used to predict the effect of sound reflections in the far field. As in many cases these

  20. Nonlinear Bayesian Estimation of BOLD Signal under Non-Gaussian Noise

    Directory of Open Access Journals (Sweden)

    Ali Fahim Khan

    2015-01-01

    Full Text Available Modeling the blood oxygenation level dependent (BOLD signal has been a subject of study for over a decade in the neuroimaging community. Inspired from fluid dynamics, the hemodynamic model provides a plausible yet convincing interpretation of the BOLD signal by amalgamating effects of dynamic physiological changes in blood oxygenation, cerebral blood flow and volume. The nonautonomous, nonlinear set of differential equations of the hemodynamic model constitutes the process model while the weighted nonlinear sum of the physiological variables forms the measurement model. Plagued by various noise sources, the time series fMRI measurement data is mostly assumed to be affected by additive Gaussian noise. Though more feasible, the assumption may cause the designed filter to perform poorly if made to work under non-Gaussian environment. In this paper, we present a data assimilation scheme that assumes additive non-Gaussian noise, namely, the e-mixture noise, affecting the measurements. The proposed filter MAGSF and the celebrated EKF are put to test by performing joint optimal Bayesian filtering to estimate both the states and parameters governing the hemodynamic model under non-Gaussian environment. Analyses using both the synthetic and real data reveal superior performance of the MAGSF as compared to EKF.

  1. Linear and non-linear energy barriers in systems of interacting single-domain ferromagnetic particles

    International Nuclear Information System (INIS)

    Petrila, Iulian; Bodale, Ilie; Rotarescu, Cristian; Stancu, Alexandru

    2011-01-01

    A comparative analysis between linear and non-linear energy barriers used for modeling statistical thermally-excited ferromagnetic systems is presented. The linear energy barrier is obtained by new symmetry considerations about the anisotropy energy and the link with the non-linear energy barrier is also presented. For a relevant analysis we compare the effects of linear and non-linear energy barriers implemented in two different models: Preisach-Neel and Ising-Metropolis. The differences between energy barriers which are reflected in different coercive field dependence of the temperature are also presented. -- Highlights: → The linear energy barrier is obtained from symmetry considerations. → The linear and non-linear energy barriers are calibrated and implemented in Preisach-Neel and Ising-Metropolis models. → The temperature and time effects of the linear and non-linear energy barriers are analyzed.

  2. Modeling environmental noise exceedances using non-homogeneous Poisson processes.

    Science.gov (United States)

    Guarnaccia, Claudio; Quartieri, Joseph; Barrios, Juan M; Rodrigues, Eliane R

    2014-10-01

    In this work a non-homogeneous Poisson model is considered to study noise exposure. The Poisson process, counting the number of times that a sound level surpasses a threshold, is used to estimate the probability that a population is exposed to high levels of noise a certain number of times in a given time interval. The rate function of the Poisson process is assumed to be of a Weibull type. The presented model is applied to community noise data from Messina, Sicily (Italy). Four sets of data are used to estimate the parameters involved in the model. After the estimation and tuning are made, a way of estimating the probability that an environmental noise threshold is exceeded a certain number of times in a given time interval is presented. This estimation can be very useful in the study of noise exposure of a population and also to predict, given the current behavior of the data, the probability of occurrence of high levels of noise in the near future. One of the most important features of the model is that it implicitly takes into account different noise sources, which need to be treated separately when using usual models.

  3. Status of conversion of DOE standards to non-Government standards

    Energy Technology Data Exchange (ETDEWEB)

    Moseley, H.L.

    1992-07-01

    One major goal of the DOE Technical Standards Program is to convert existing DOE standards into non-Government standards (NGS's) where possible. This means that a DOE standard may form the basis for a standards-writing committee to produce a standard in the same subject area using the non-Government standards consensus process. This report is a summary of the activities that have evolved to effect conversion of DOE standards to NGSs, and the status of current conversion activities. In some cases, all requirements in a DOE standard will not be incorporated into the published non-Government standard because these requirements may be considered too restrictive or too specific for broader application by private industry. If requirements in a DOE standard are not incorporated in a non-Government standard and the requirements are considered necessary for DOE program applications, the DOE standard will be revised and issued as a supplement to the non-Government standard. The DOE standard will contain only those necessary requirements not reflected by the non-Government standard. Therefore, while complete conversion of DOE standards may not always be realized, the Department's technical standards policy as stated in Order 1300.2A has been fully supported in attempting to make maximum use of the non-Government standard.

  4. Status of conversion of DOE standards to non-Government standards

    Energy Technology Data Exchange (ETDEWEB)

    Moseley, H.L.

    1992-07-01

    One major goal of the DOE Technical Standards Program is to convert existing DOE standards into non-Government standards (NGS`s) where possible. This means that a DOE standard may form the basis for a standards-writing committee to produce a standard in the same subject area using the non-Government standards consensus process. This report is a summary of the activities that have evolved to effect conversion of DOE standards to NGSs, and the status of current conversion activities. In some cases, all requirements in a DOE standard will not be incorporated into the published non-Government standard because these requirements may be considered too restrictive or too specific for broader application by private industry. If requirements in a DOE standard are not incorporated in a non-Government standard and the requirements are considered necessary for DOE program applications, the DOE standard will be revised and issued as a supplement to the non-Government standard. The DOE standard will contain only those necessary requirements not reflected by the non-Government standard. Therefore, while complete conversion of DOE standards may not always be realized, the Department`s technical standards policy as stated in Order 1300.2A has been fully supported in attempting to make maximum use of the non-Government standard.

  5. Noise-Induced Modulation of the Relaxation Kinetics around a Non-Equilibrium Steady State of Non-Linear Chemical Reaction Networks

    OpenAIRE

    Ramaswamy, Rajesh; Sbalzarini, Ivo F; González-Segredo, Nélido

    2011-01-01

    Stochastic effects from correlated noise non-trivially modulate the kinetics of non-linear chemical reaction networks. This is especially important in systems where reactions are confined to small volumes and reactants are delivered in bursts. We characterise how the two noise sources confinement and burst modulate the relaxation kinetics of a non-linear reaction network around a non-equilibrium steady state. We find that the lifetimes of species change with burst input and confinement. Confi...

  6. Repeatability and reproducibility of in situ measurements of sound reflection and airborne sound insulation index of noise barriers

    NARCIS (Netherlands)

    Garai, M.; Schoen, E.; Behler, G.; Bragado, B.; Chudalla, M.; Conter, M.; Defrance, J.; Demizieux, P.; Glorieux, C.; Guidorzi, P.

    2014-01-01

    In Europe, in situ measurements of sound reflection and airborne sound insulation of noise barriers are usually done according to CEN/TS 1793-5. This method has been improved substantially during the EU funded QUIESST collaborative project. Within the same framework, an inter-laboratory test has

  7. The Traffic Noise Index: A Method of Controlling Noise Nuisance.

    Science.gov (United States)

    Langdon, F. J.; Scholes, W. E.

    This building research survey is an analysis of the social nuisance caused by urban motor ways and their noise. The Traffic Noise Index is used to indicate traffic noises and their effects on architectural designs and planning, while suggesting the need for more and better window insulation and acoustical barriers. Overall concern is for--(1)…

  8. 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....

  9. Impact of non-white noises in pulse amplitude measurements: a time-domain approach

    International Nuclear Information System (INIS)

    Pullia, A.

    1998-01-01

    The contribution of the 1/f-noise to the spectral line broadening in pulse amplitude measurements is derived with a time-domain analysis. The known time-domain relationships which provide the contributions of the series and parallel white noises are generalised for the case of 1/f and other typical non-white noises, by using the fractional derivative of either the system impulse response (time-invariant linear filters) or its weight function folded (time-variant linear filters). It is shown that a time-domain approach is also effective to determine the contribution of Lorentzian noises. A simple rule suitable to derive numerically the fractional derivative is given, which permits to calculate the effect of non-white noises even when the filter impulse response is not known analytically but only in sampled form. (orig.)

  10. Auditory and Non-Auditory Contributions for Unaided Speech Recognition in Noise as a Function of Hearing Aid Use.

    Science.gov (United States)

    Gieseler, Anja; Tahden, Maike A S; Thiel, Christiane M; Wagener, Kirsten C; Meis, Markus; Colonius, Hans

    2017-01-01

    Differences in understanding speech in noise among hearing-impaired individuals cannot be explained entirely by hearing thresholds alone, suggesting the contribution of other factors beyond standard auditory ones as derived from the audiogram. This paper reports two analyses addressing individual differences in the explanation of unaided speech-in-noise performance among n = 438 elderly hearing-impaired listeners ( mean = 71.1 ± 5.8 years). The main analysis was designed to identify clinically relevant auditory and non-auditory measures for speech-in-noise prediction using auditory (audiogram, categorical loudness scaling) and cognitive tests (verbal-intelligence test, screening test of dementia), as well as questionnaires assessing various self-reported measures (health status, socio-economic status, and subjective hearing problems). Using stepwise linear regression analysis, 62% of the variance in unaided speech-in-noise performance was explained, with measures Pure-tone average (PTA), Age , and Verbal intelligence emerging as the three most important predictors. In the complementary analysis, those individuals with the same hearing loss profile were separated into hearing aid users (HAU) and non-users (NU), and were then compared regarding potential differences in the test measures and in explaining unaided speech-in-noise recognition. The groupwise comparisons revealed significant differences in auditory measures and self-reported subjective hearing problems, while no differences in the cognitive domain were found. Furthermore, groupwise regression analyses revealed that Verbal intelligence had a predictive value in both groups, whereas Age and PTA only emerged significant in the group of hearing aid NU.

  11. Detecting the presence of a magnetic field under Gaussian and non-Gaussian noise by adaptive measurement

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yuan-Mei; Li, Jun-Gang, E-mail: jungl@bit.edu.cn; Zou, Jian

    2017-06-15

    Highlights: • Adaptive measurement strategy is used to detect the presence of a magnetic field. • Gaussian Ornstein–Uhlenbeck noise and non-Gaussian noise have been considered. • Weaker magnetic fields may be more easily detected than some stronger ones. - Abstract: By using the adaptive measurement method we study how to detect whether a weak magnetic field is actually present or not under Gaussian noise and non-Gaussian noise. We find that the adaptive measurement method can effectively improve the detection accuracy. For the case of Gaussian noise, we find the stronger the magnetic field strength, the easier for us to detect the magnetic field. Counterintuitively, for non-Gaussian noise, some weaker magnetic fields are more likely to be detected rather than some stronger ones. Finally, we give a reasonable physical interpretation.

  12. Non-standard patch test

    Directory of Open Access Journals (Sweden)

    Astri Adelia

    2018-06-01

    Full Text Available In managing contact dermatitis, identification of the causative agent is essential to prevent recurrent complaints. Patch test is the gold standard to identify the causative agent. Nowadays, there are many patch test standard materials available in the market, but do not include all the materials that potentially cause contact dermatitis. Patch test using patient’s own products or later we refer to as non-standard materials, is very helpful in identifying the causative agents of contact dermatitis. Guidance is needed in producing non-standard patch test materials in order to avoid test results discrepancy.

  13. Non-white noise in fMRI: Does modelling have an impact?

    DEFF Research Database (Denmark)

    Lund, Torben Ellegaard; Madsen, Kristoffer Hougaard; Sidaros, Karam

    2006-01-01

    are typically modelled as an autoregressive (AR) process. In this paper, we propose an alternative approach: Nuisance Variable Regression (NVR). By inclusion of confounding effects in a general linear model (GLM), we first confirm that the spatial distribution of the various fMRI noise sources is similar......The sources of non-white noise in Blood Oxygenation Level Dependent (BOLD) functional magnetic resonance imaging (fMRI) are many. Familiar sources include low-frequency drift due to hardware imperfections, oscillatory noise due to respiration and cardiac pulsation and residual movement artefacts...

  14. Acoustical topology optimization for Zwicker's loudness model - Application to noise barriers

    DEFF Research Database (Denmark)

    Kook, Junghwan; Koo, Kunmo; Hyun, Jaeyub

    2012-01-01

    acoustic properties may not represent adequate parameters for optimizing acoustic devices. In this paper, we first present a design method for acoustical topology optimization by considering human's subjective conception of sound. To consider human hearing characteristics. Zwicker's loudness is calculated...... according to DIN45631 (ISO 532B). The main objective of this work is to minimize the main specific loudness of a target critical band rate by optimizing the distribution of the reflecting material in a design domain. The Helmholtz equation is used to model acoustic wave propagation and, it is solved using...... the finite element method. The sensitivity of the main specific loudness is calculated using the adjoint variable method and the chain rule. To demonstrate the effectiveness of the proposed method, various examples of noise barriers are presented with different source and receiver locations. The results...

  15. The influence of fast neutron irradiation on the noise properties of silicon surface-barrier detectors

    International Nuclear Information System (INIS)

    Dabrowski, W.; Korbel, K.

    1988-01-01

    The susceptibility to the fast neutron irradiation of silicon surface-barrier detectors has been investigated. It was shown that the 1/f-noise decreases substantially with increasing fluence in the range from 10 10 n/cm 2 to 10 11 n/cm 2 . The deterioration of the detector performance is caused mainly by the positively-charged defects induced by the radiation. The critical value of the neutron fluence, at which the detector performance begins to be worsened was also determined. 5 refs., 5 figs. (author)

  16. Shot-noise at a Fermi-edge singularity: Non-Markovian dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Ubbelohde, N.; Maire, N.; Haug, R. J. [Institut für Festkörperphysik, Leibniz Universität Hannover, Appelstraße 2, D-30167 Hannover (Germany); Roszak, K. [Institute of Physics, Wrocław University of Technology, PL-50370 Wrocław (Poland); Hohls, F. [Physikalisch-Technische Bundesanstalt, D-38116 Braunschweig (Germany); Novotný, T. [Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, CZ-12116 Prague (Czech Republic)

    2013-12-04

    For an InAs quantum dot we study the current shot noise at a Fermi-edge singularity in low temperature cross-correlation measurements. In the regime of the interaction effect the strong suppression of noise observed at zero magnetic field and the sequence of enhancement and suppression in magnetic field go beyond a Markovian master equation model. Qualitative and quantitative agreement can however be achieved by a generalized master equation model taking non-Markovian dynamics into account.

  17. Non-auditory effects of noise in industry. VI. A final field study in industry

    NARCIS (Netherlands)

    van Dijk, F. J.; Souman, A. M.; de Vries, F. F.

    1987-01-01

    Non-auditory effects of noise were studied among 539 male workers from seven industries. The LAeq, assessed by personal noise dosimetry, has been used to study acute effects. Various indices of total noise exposure, involving level and duration, were developed for long-term effect studies. In the

  18. Comparative Analysis of AHP-TOPSIS and Fuzzy AHP Models in Selecting Appropriate Nanocomposites for Environmental Noise Barrier Applications

    Science.gov (United States)

    Naderzadeh, Mahdiyeh; Arabalibeik, Hossein; Monazzam, Mohammad Reza; Ghasemi, Ismaeil

    Choosing the right material in the design of environmental noise barriers has always been a challenging issue in acoustics. In less-developed countries, the material selection is affected by many factors from various aspects, which makes the decision-making very complicated. This study attempts to compare and assign weights to the most important indices affecting the choice of appropriate noise barrier material. These criteria include absorption coefficient, transparency, tensile modulus, strength at yield, elongation at break, impact strength, flexural modulus, hardness, and cost. For this purpose, experts' opinions was gathered through a total of 13 questionnaires and used for assigning weights by Analytic Hierarchy Process (AHP) and Fuzzy Analytic Hierarchy process (FAHP) techniques. According to the AHP results, impact strength, with only a minor difference of 0.093 compared to the AHP, was recognized as the most important criterion. Finally, the optimal composite material was selected using two different methods; first by Technique for Order-Preference by Similarity to Ideal Solution (TOPSIS) based on the weights obtained from AHP, and next by directly applying the obtained weights from FAHP to the true measured values of parameters. As the results show, in both abovementioned methods, Polycarbonate-SiO2 0.3% with roughened surface (PCSI3-R) received the highest score and was selected as the preferred composite material. Given the close similarity of the results, to determine the superiority of one method over the other, some noise was added to the original data set from the mechanical and acoustic tests and then the variance of the changes in the final orders of preferences was calculated. This indicates the robustness of the method against the measurement errors and noise. The results shows that under the same circumstances, the overall order shift variance in the classic TOPSIS is six times higher than that of the fuzzy AHP method.

  19. Light Barrier for Non-Foil Packaging

    Science.gov (United States)

    2010-12-16

    foil and all-plastic materials were retorted and a second set of all-plastic packaged entrees were Microwave Sterilized on the Washington State...Copolymers for Retort Applications; SPE Polyolefins and Flexible Packaging Conference: Society of Plastics Engineers. Newtown. CT, 43pp. Thellen C...Final Scientific Report Light Barrier for Non-Foil Packaging Contract No. W911QY-08-C-0132 Final Scientific Report Contract No. W911QY-08-C-0132

  20. A random-parametric reactor model with direct feedback and non-white noise

    International Nuclear Information System (INIS)

    Sako, O.; Taniguchi, A.; Kuroda, Y.

    1982-01-01

    The effects of multiplicative direct power feedback and non-white reactivity noise on the fluctuations of the neutron density are studied, based on the master equation using the cumulant expansion and the system-size expansion. The results obtained are the following: non-whiteness of reactivity noise reduces the variance of neutron density, as well as the level of the power spectral density. The nonlinear effect of power feedback gives rise to at least a pair of corner frequencies, in contrast to the single corner frequency in linearized case. (author)

  1. Green noise wall construction and evaluation.

    Science.gov (United States)

    2011-09-01

    This report details the research performed under Phase I of a research study titled Green Noise Wall Construction and Evaluation that looks into the feasibility of using green noise barriers as a noise mitigation option in Ohio. This phase incl...

  2. Proceedings of the 6th International Congress on Noise as a Public Health Problem, volume 2

    Science.gov (United States)

    1993-07-01

    The 160 papers from the congress are presented. Topics covered include the following: noise induced hearing loss; noise and communication; community response to noise; noise and animal life; non-auditory physiological effects; influence of noise on performance and behavior; noise and disturbed sleep; and regulations and standards.

  3. Recent advances in research on non-auditory effects of community noise

    Directory of Open Access Journals (Sweden)

    Belojević Goran

    2016-01-01

    Full Text Available Non-auditory effects of noise on humans have been intensively studied in the last four decades. The International Commission on Biological Effects of Noise has been following scientific advances in this field by organizing international congresses from the first one in 1968 in Washington, DC, to the 11th congress in Nara, Japan, in 2014. There is already a large scientific body of evidence on the effects of noise on annoyance, communication, performance and behavior, mental health, sleep, and cardiovascular functions including relationship with hypertension and ischemic heart disease. In the last five years new issues in this field have been tackled. Large epidemiological studies on community noise have reported its relationship with breast cancer, stroke, type 2 diabetes, and obesity. It seems that noise-induced sleep disturbance may be one of the mediating factors in these effects. Given a large public health importance of the above-mentioned diseases, future studies should more thoroughly address the mechanisms underlying the reported association with community noise exposure. [Projekat Ministarstva nauke Republike Srbije, br. 175078

  4. Evaluation of model-based versus non-parametric monaural noise-reduction approaches for hearing aids.

    Science.gov (United States)

    Harlander, Niklas; Rosenkranz, Tobias; Hohmann, Volker

    2012-08-01

    Single channel noise reduction has been well investigated and seems to have reached its limits in terms of speech intelligibility improvement, however, the quality of such schemes can still be advanced. This study tests to what extent novel model-based processing schemes might improve performance in particular for non-stationary noise conditions. Two prototype model-based algorithms, a speech-model-based, and a auditory-model-based algorithm were compared to a state-of-the-art non-parametric minimum statistics algorithm. A speech intelligibility test, preference rating, and listening effort scaling were performed. Additionally, three objective quality measures for the signal, background, and overall distortions were applied. For a better comparison of all algorithms, particular attention was given to the usage of the similar Wiener-based gain rule. The perceptual investigation was performed with fourteen hearing-impaired subjects. The results revealed that the non-parametric algorithm and the auditory model-based algorithm did not affect speech intelligibility, whereas the speech-model-based algorithm slightly decreased intelligibility. In terms of subjective quality, both model-based algorithms perform better than the unprocessed condition and the reference in particular for highly non-stationary noise environments. Data support the hypothesis that model-based algorithms are promising for improving performance in non-stationary noise conditions.

  5. Foundational aspects of non standard mathematics

    CERN Document Server

    Ballard, David

    1994-01-01

    This work proposes a major new extension of "non"standard mathematics. Addressed to a general mathematical audience, the book is intended to be philosophically provocative. The model theory on which "non"standard mathematics has been based is first reformulated within point set topology, which facilitates proofs and adds perspective. These topological techniques are then used to give new, uniform conservativity proofs for the various versions of "non"standard mathematics proposed by Nelson, Hrbáček, and Kawai. The proofs allow for sharp comparison. Addressing broader issues, Ballard then argues that what is novel in these forms of "non"standard mathematics is the introduction, however tentative, of relativity in one's mathematical environment. This hints at the possibility of a mathematical environment which is radically relativistic. The work's major and final feature is to present and prove conservative a version of "non"standard mathematics which, for the first time, illustrates this full radical relativ...

  6. Virtual Reality Platform Based Simulation System of Environmental Noise Abatement Research

    Science.gov (United States)

    Yijun, Liu; Yu, Fang; Xiaoman, He; Yongyou, Wang

    The general mathematic mode of computing noise abatement is commonly used for most project planning and appraisal of environmental noise abatement projects. However, the inconvenient and impracticable mode and algorithm usually cannot meet the real world computation and testing. Therefore, a more practicable abatement mode and algorithm (multiple noise sources with multiband under sound barriers) which had been applied to VR based simulation system. That implemented the function of real-time demonstrating noise scattering condition within 3D virtual space, furthermore, with sound barriers added in 3D scene, the effectiveness of denoise by sound barriers also can be demonstrated within this system. That provides a significant solution for environmental noise abatement projects as a whole.

  7. Non-statutory barriers and incentives to stakeholder participation in ...

    African Journals Online (AJOL)

    Non-statutory barriers and incentives to stakeholder participation in reducing water pollution: A South African case study. ... were found to be the major impediments preventing staff at government agencies and parastatals from motivating other ...

  8. Stochastic differential calculus for Gaussian and non-Gaussian noises: A critical review

    Science.gov (United States)

    Falsone, G.

    2018-03-01

    In this paper a review of the literature works devoted to the study of stochastic differential equations (SDEs) subjected to Gaussian and non-Gaussian white noises and to fractional Brownian noises is given. In these cases, particular attention must be paid in treating the SDEs because the classical rules of the differential calculus, as the Newton-Leibnitz one, cannot be applied or are applicable with many difficulties. Here all the principal approaches solving the SDEs are reported for any kind of noise, highlighting the negative and positive properties of each one and making the comparisons, where it is possible.

  9. Lifting Primordial Non-Gaussianity Above the Noise

    NARCIS (Netherlands)

    Welling, Yvette; Woude, Drian van der; Pajer, Enrico

    2016-01-01

    Primordial non-Gaussianity (PNG) in Large Scale Structures is obfuscated by the many additional sources of non-linearity. Within the Effective Field Theory approach to Standard Perturbation Theory, we show that matter non-linearities in the bispectrum can be modeled sufficiently well to strengthen

  10. Noise characterization of oil and gas operations.

    Science.gov (United States)

    Radtke, Cameron; Autenrieth, Daniel A; Lipsey, Tiffany; Brazile, William J

    2017-08-01

    In cooperation with The Colorado Oil and Gas Conservation Commission, researchers at Colorado State University performed area noise monitoring at 23 oil and gas sites throughout Northern Colorado. The goals of this study were to: (1) measure and compare the noise levels for the different phases of oil and gas development sites; (2) evaluate the effectiveness of noise barriers; and (3) determine if noise levels exceeded the Colorado Oil and Gas Conservation Commission noise limits. The four phases of oil and gas development include drilling, hydraulic fracturing, completion and production. Noise measurements were collected using the A- and C-weighted sound scales. Octave band analysis was also performed to characterize the frequency spectra of the noise measurements.  Noise measurements were collected using noise dosimeters and a hand-held sound-level meter at specified distances from the development sites in each cardinal direction. At 350 ft (107 m), drilling, hydraulic fracturing, and completion sites without noise barriers exceeded the maximum permissible noise levels for residential and commercial zones (55 dBA and 60 dBA, respectively). In addition, drilling and hydraulic fracturing sites with noise barriers exceeded the maximum permissible noise level for residential zones (55 dBA). However, during drilling, hydraulic fracturing, and completion operations, oil producers are allowed an exception to the noise permissible limits in that they only must comply with the industrial noise limit (80 dBA). It is stated in Rule 604.c.(2)A. that: "Operations involving pipeline or gas facility installation or maintenance, the use of a drilling rig, completion rig, workover rig, or stimulation is subject to the maximum permissible noise levels for industrial zones (80dBA)." [8] Production sites were within the Colorado Oil and Gas Conservation Commission permissible noise level criteria for all zones. At 350 ft (107 m) from the noise source, all drilling

  11. A statistical background noise correction sensitive to the steadiness of background noise.

    Science.gov (United States)

    Oppenheimer, Charles H

    2016-10-01

    A statistical background noise correction is developed for removing background noise contributions from measured source levels, producing a background noise-corrected source level. Like the standard background noise corrections of ISO 3741, ISO 3744, ISO 3745, and ISO 11201, the statistical background correction increases as the background level approaches the measured source level, decreasing the background noise-corrected source level. Unlike the standard corrections, the statistical background correction increases with steadiness of the background and is excluded from use when background fluctuation could be responsible for measured differences between the source and background noise levels. The statistical background noise correction has several advantages over the standard correction: (1) enveloping the true source with known confidence, (2) assuring physical source descriptions when measuring sources in fluctuating backgrounds, (3) reducing background corrected source descriptions by 1 to 8 dB for sources in steady backgrounds, and (4) providing a means to replace standardized background correction caps that incentivize against high precision grade methods.

  12. Barriers to the widespread adoption of health data standards: an exploratory qualitative study in tertiary healthcare organizations in Saudi Arabia.

    Science.gov (United States)

    Alkraiji, Abdullah; Jackson, Thomas; Murray, Ian

    2013-04-01

    Although health data standards are perceived to be the essential solution for interoperability barriers within medical IT systems, the level of adoption of those standards still remains frustratingly low. Little is known about the barriers facing their adoption within the healthcare organizations context. In addressing this gap in the literature, based on IT related standards adoption theories such as Diffusion of Innovation Theory and the theories surrounding the Economics of Standards, a qualitative multiple-case study was undertaken in Saudi Arabia to investigate those barriers. The results exposed that few standards were adopted because of four broad reasons, managerial, technical, educational and governmental. While some of the findings can be rooted to those related standards theories, others can be underpinned through the normative literature. Core barriers are the lack of a national regulator and a data exchange plan, and the lack of an adequate policy regarding medical IT systems and information management and national healthcare system; also important are technical barriers and the switching costs to the standards. The outcome of this study can be used in forming effective interventions when planning to use health data standards and, in particular those in developing countries.

  13. QUIESST Guidebook to Noise Reducing Devices optimisation

    NARCIS (Netherlands)

    Clairbois, J.P.; Roo, F. de; Garai, M.; Conter, M.; Defrance, J.; Oltean-Dumbrava, C.A.; Durso, C.

    2012-01-01

    The aim of this guidebook is to become a reference tool for noise mitigation through a better use of Noise Reducing Devices (NRD) (e.g.: Noise Barriers or sound Absorptive Claddings). It targets all the stakeholders involved in NRD projects (designers, manufacturers, authorities, construction

  14. Fault-tolerant quantum computation for local non-Markovian noise

    International Nuclear Information System (INIS)

    Terhal, Barbara M.; Burkard, Guido

    2005-01-01

    We derive a threshold result for fault-tolerant quantum computation for local non-Markovian noise models. The role of error amplitude in our analysis is played by the product of the elementary gate time t 0 and the spectral width of the interaction Hamiltonian between system and bath. We discuss extensions of our model and the applicability of our analysis

  15. Non-Stationary Rician Noise Estimation in Parallel MRI Using a Single Image: A Variance-Stabilizing Approach.

    Science.gov (United States)

    Pieciak, Tomasz; Aja-Fernandez, Santiago; Vegas-Sanchez-Ferrero, Gonzalo

    2017-10-01

    Parallel magnetic resonance imaging (pMRI) techniques have gained a great importance both in research and clinical communities recently since they considerably accelerate the image acquisition process. However, the image reconstruction algorithms needed to correct the subsampling artifacts affect the nature of noise, i.e., it becomes non-stationary. Some methods have been proposed in the literature dealing with the non-stationary noise in pMRI. However, their performance depends on information not usually available such as multiple acquisitions, receiver noise matrices, sensitivity coil profiles, reconstruction coefficients, or even biophysical models of the data. Besides, some methods show an undesirable granular pattern on the estimates as a side effect of local estimation. Finally, some methods make strong assumptions that just hold in the case of high signal-to-noise ratio (SNR), which limits their usability in real scenarios. We propose a new automatic noise estimation technique for non-stationary Rician noise that overcomes the aforementioned drawbacks. Its effectiveness is due to the derivation of a variance-stabilizing transformation designed to deal with any SNR. The method was compared to the main state-of-the-art methods in synthetic and real scenarios. Numerical results confirm the robustness of the method and its better performance for the whole range of SNRs.

  16. Multi-Resonant-Activation for a System Only Driven by Multi-State Noise

    International Nuclear Information System (INIS)

    Li Jinghui

    2010-01-01

    We consider the escape of the particles over fluctuating potential barrier for a system only driven by a multi-state noise. It is shown that, the noise can make the particles escape over the fluctuating potential barrier in some circumstances; but in other circumstances, it can not. If the noise can make the particle escape over the fluctuating potential barrier, the mean first passage time (MFPT) can display the phenomenon of multi-resonant-activation. For this phenomenon, there are two kinds of resonant activation to appear. One is resonant activation for the MFPTs as the function of the flipping rates of the fluctuating potential barrier; the other is that for the MFPTs as the functions of the transition rates of the multi-state noise. (general)

  17. Potential facilitators and barriers to adopting standard treatment guidelines in clinical practice.

    Science.gov (United States)

    Sharma, Sangeeta; Pandit, Ajay; Tabassum, Fauzia

    2017-04-18

    Purpose The purpose of this paper is to assess medicines information sources accessed by clinicians, if sources differed in theory and practice and to find out the barriers and facilitators to effective guideline adoption. Design/methodology/approach In all, 183 doctors were surveyed. Barriers and facilitators were classified as: communication; potential adopters; innovation; organization characteristics and environmental/social/economic context. Findings Most of the clinicians accessed multiple information sources including standard treatment guidelines, but also consulted seniors/colleagues in practice. The top three factors influencing clinical practice guideline adoption were innovation characteristics, environmental context and individual characteristics. The respondents differed in the following areas: concerns about flexibility offered by the guideline; denying patients' individuality; professional autonomy; insights into gaps in current practice and evidence-based practice; changing practices with little or no benefit. Barriers included negative staff attitudes/beliefs, guideline integration into organizational structures/processes, time/resource constraints. Fearing third parties (government and insurance companies) restricting medicines reimbursement and poor liability protection offered by the guidelines emerged as the barriers. Facilitators include aligning organizational structures/processes with the innovation; providing leadership support to guide diffusion; increasing awareness and enabling early innovation during pre/in-service training, with regular feedback on outcomes and use. Practical implications Guideline adoption in clinical practice is partly within doctors' control. There are other key prevailing factors in the local context such as environmental, social context, professional and organizational culture affecting its adoption. Organizational policy and accreditation standards necessitating adherence can serve as a driver. Originality

  18. Metric and topology on a non-standard real line and non-standard space-time

    International Nuclear Information System (INIS)

    Tahir Shah, K.

    1981-04-01

    We study metric and topological properties of extended real line R* and compare it with the non-standard model of real line *R. We show that some properties, like triangular inequality, cannot be carried over R* from R. This confirms F. Wattenberg's result for measure theory on Dedekind completion of *R. Based on conclusions from these results we propose a non-standard model of space-time. This space-time is without undefined objects like singularities. (author)

  19. Modeling and Compensating Temperature-Dependent Non-Uniformity Noise in IR Microbolometer Cameras

    Directory of Open Access Journals (Sweden)

    Alejandro Wolf

    2016-07-01

    Full Text Available Images rendered by uncooled microbolometer-based infrared (IR cameras are severely degraded by the spatial non-uniformity (NU noise. The NU noise imposes a fixed-pattern over the true images, and the intensity of the pattern changes with time due to the temperature instability of such cameras. In this paper, we present a novel model and a compensation algorithm for the spatial NU noise and its temperature-dependent variations. The model separates the NU noise into two components: a constant term, which corresponds to a set of NU parameters determining the spatial structure of the noise, and a dynamic term, which scales linearly with the fluctuations of the temperature surrounding the array of microbolometers. We use a black-body radiator and samples of the temperature surrounding the IR array to offline characterize both the constant and the temperature-dependent NU noise parameters. Next, the temperature-dependent variations are estimated online using both a spatially uniform Hammerstein-Wiener estimator and a pixelwise least mean squares (LMS estimator. We compensate for the NU noise in IR images from two long-wave IR cameras. Results show an excellent NU correction performance and a root mean square error of less than 0.25 ∘ C, when the array’s temperature varies by approximately 15 ∘ C.

  20. Noise Enhanced Stability

    International Nuclear Information System (INIS)

    Spagnolo, B.; Agudov, N.V.; Dubkov, A.A.

    2004-01-01

    The noise can stabilize a fluctuating or a periodically driven metastable state in such a way that the system remains in this state for a longer time than in the absence of white noise. This is the noise enhanced stability phenomenon, observed experimentally and numerically in different physical systems. After shortly reviewing all the physical systems where the phenomenon was observed, the theoretical approaches used to explain the effect are presented. Specifically the conditions to observe the effect in systems: (a) with periodical driving force, and (b) with random dichotomous driving force, are discussed. In case (b) we review the analytical results concerning the mean first passage time and the nonlinear relaxation time as a function of the white noise intensity, the parameters of the potential barrier, and of the dichotomous noise. (author)

  1. Does non-standard work mean non-standard health? Exploring links between non-standard work schedules, health behavior, and well-being

    Directory of Open Access Journals (Sweden)

    Megan R. Winkler

    2018-04-01

    Full Text Available The last century has seen dramatic shifts in population work circumstances, leading to an increasing normalization of non-standard work schedules (NSWSs, defined as non-daytime, irregular hours. An ever-growing body of evidence links NSWSs to a host of non-communicable chronic conditions; yet, these associations primarily concentrate on the physiologic mechanisms created by circadian disruption and insufficient sleep. While important, not all NSWSs create such chronobiologic disruption, and other aspects of working time and synchronization could be important to the relationships between work schedules and chronic disease. Leveraging survey data from Project EAT, a population-based study with health-related behavioral and psychological data from U.S. adults aged 25–36 years, this study explored the risks for a broad range of less healthful behavioral and well-being outcomes among NSWS workers compared to standard schedule workers (n = 1402. Variations across different NSWSs (evening, night/rotating, and irregular schedules were also explored. Results indicated that, relative to standard schedule workers, workers with NSWSs are at increased risk for non-optimal sleep, substance use, greater recreational screen time, worse dietary practices, obesity, and depression. There was minimal evidence to support differences in relative risks across workers with different types of NSWSs. The findings provide insight into the potential links between NSWSs and chronic disease and indicate the relevancy social disruption and daily health practices may play in the production of health and well-being outcomes among working populations. Keywords: United States, Work schedule tolerance, Health behavior, Mental health, Substance abuse, Obesity

  2. Bilayer graphene lattice-layer entanglement in the presence of non-Markovian phase noise

    Science.gov (United States)

    Bittencourt, Victor A. S. V.; Blasone, Massimo; Bernardini, Alex E.

    2018-03-01

    The evolution of single particle excitations of bilayer graphene under effects of non-Markovian noise is described with focus on the decoherence process of lattice-layer (LL) maximally entangled states. Once the noiseless dynamics of an arbitrary initial state is identified by the correspondence between the tight-binding Hamiltonian for the AB-stacked bilayer graphene and the Dirac equation—which includes pseudovectorlike and tensorlike field interactions—the noisy environment is described as random fluctuations on bias voltage and mass terms. The inclusion of noisy dynamics reproduces the Ornstein-Uhlenbeck processes: A non-Markovian noise model with a well-defined Markovian limit. Considering that an initial amount of entanglement shall be dissipated by the noise, two profiles of dissipation are identified. On one hand, for eigenstates of the noiseless Hamiltonian, deaths and revivals of entanglement are identified along the oscillation pattern for long interaction periods. On the other hand, for departing LL Werner and Cat states, the entanglement is suppressed although, for both cases, some identified memory effects compete with the pure noise-induced decoherence in order to preserve the the overall profile of a given initial state.

  3. Non-Saccharomyces yeasts protect against epithelial cell barrier disruption induced by Salmonella enterica subsp. enterica serovar Typhimurium.

    Science.gov (United States)

    Smith, I M; Baker, A; Arneborg, N; Jespersen, L

    2015-11-01

    The human gastrointestinal epithelium makes up the largest barrier separating the body from the external environment. Whereas invasive pathogens cause epithelial barrier disruption, probiotic micro-organisms modulate tight junction regulation and improve epithelial barrier function. In addition, probiotic strains may be able to reduce epithelial barrier disruption caused by pathogenic species. The aim of this study was to explore non-Saccharomyces yeast modulation of epithelial cell barrier function in vitro. Benchmarking against established probiotic strains, we evaluated the ability of four nonpathogenic yeast species to modulate transepithelial electrical resistance (TER) across a monolayer of differentiated human colonocytes (Caco-2 cells). Further, we assessed yeast modulation of a Salmonella Typhimurium-induced epithelial cell barrier function insult. Our findings demonstrate distinct patterns of non-Saccharomyces yeast modulation of epithelial cell barrier function. While the established probiotic yeast Saccharomyces boulardii increased TER across a Caco-2 monolayer by 30%, Kluyveromyces marxianus exhibited significantly stronger properties of TER enhancement (50% TER increase). In addition, our data demonstrate significant yeast-mediated modulation of Salmonella-induced epithelial cell barrier disruption and identify K. marxianus and Metschnikowia gruessii as two non-Saccharomyces yeasts capable of protecting human epithelial cells from pathogen invasion. This study demonstrates distinct patterns of non-Saccharomyces yeast modulation of epithelial cell barrier function in vitro. Further, our data demonstrate significant yeast-mediated modulation of Salmonella Typhimurium-induced epithelial cell barrier disruption and identify Kluyveromyces marxianus and Metschnikowia gruessii as two non-Saccharomyces yeasts capable of protecting human epithelial cells from pathogen invasion. This study is the first to demonstrate significant non-Saccharomyces yeast

  4. Relative resilience to noise of standard and sequential approaches to measurement-based quantum computation

    Science.gov (United States)

    Gallagher, C. B.; Ferraro, A.

    2018-05-01

    A possible alternative to the standard model of measurement-based quantum computation (MBQC) is offered by the sequential model of MBQC—a particular class of quantum computation via ancillae. Although these two models are equivalent under ideal conditions, their relative resilience to noise in practical conditions is not yet known. We analyze this relationship for various noise models in the ancilla preparation and in the entangling-gate implementation. The comparison of the two models is performed utilizing both the gate infidelity and the diamond distance as figures of merit. Our results show that in the majority of instances the sequential model outperforms the standard one in regard to a universal set of operations for quantum computation. Further investigation is made into the performance of sequential MBQC in experimental scenarios, thus setting benchmarks for possible cavity-QED implementations.

  5. RF dynamic and noise performance of Metallic Source/Drain SOI n-MOSFETs

    Science.gov (United States)

    Martin, Maria J.; Pascual, Elena; Rengel, Raúl

    2012-07-01

    This paper presents a detailed study of the RF and noise performance of n-type Schottky barrier (SB) MOSFETs with a particular focus on the influence of the Schottky barrier height (SBH) on the main dynamic and noise figures of merit. With this aim, a 2D Monte Carlo simulator including tunnelling transport across Schottky interfaces has been developed, with special care to consider quantum transmission coefficients and the influence of image charge effects at the Schottky junctions. Particular attention is paid to the microscopic transport features, including carrier mean free paths or number of scattering events along the channel for investigating the optimization of the device topology and the strategic concepts related to the noise performance of this new architecture. A more effective control of the gate electrode over drain current for low SBH (discussed in terms of internal physical quantities) is translated into an enhanced transconductance gm, cut-off frequency fT, and non-quasistatic dynamic parameters. The drain and gate intrinsic noise sources show a noteworthy degradation with the SBH reduction due to the increased current, influence of hot carriers and reduced number of phonon scatterings. However, the results evidence that this effect is counterbalanced by the extremely improved dynamic performance in terms of gm and fT. Therefore, the deterioration of the intrinsic noise performance of the SB-MOSFET has no significant impact on high-frequency noise FoMs as NFmin, Rn and Gass for low SBH and large gate overdrive conditions. The role of the SBH on Γopt, optimum noise reactance and susceptance has been also analyzed.

  6. Multi-Barrier Protection of Drinking Water Systems in Ontario: A Comparison of First Nation and Non-First Nation Communities

    Directory of Open Access Journals (Sweden)

    Budhendra Singh

    2012-11-01

    Full Text Available In some way or another, all levels of government in Canada and First Nations share responsibility to implement multi-barrier protection of drinking water. The goal is to protect water from source to tap to minimize risk so that people have access to adequate and safe drinking water. The federal government has committed to assist First Nations achieve comparable levels of service standards available to non-First Nation communities. However, several recent reports on the status of drinking water services standards in First Nations indicate that people in these communities often experience greater health risks than those living off reserves. Using the federal drinking water risk evaluation guidelines, the capacities of First Nations and non-First Nations in Ontario to implement multi-barrier protection of their drinking water systems are compared. The Risk Level Evaluation Guidelines for Water and Wastewater Treatment in First Nation Communities rank drinking water systems as low, medium, or high risk based on information about source water, system design, system operation, reporting, and operator expertise. The risk evaluation scores for First Nations drinking water systems were obtained from Aboriginal Affairs and Northern Development Canada. A survey based on the federal Risk Level Evaluation Guidelines was sent to non-First Nation communities throughout Ontario with 54 communities responding. The capacity among First Nations was variable throughout the province, whereas all of the municipalities were in the low risk category, even small and northern non-First Nation community water systems. It is clear that the financial and technological capacity issues should be addressed regardless of the legislative and regulatory regime that is established. The current governance and management structure does not appear to be significantly reducing the gap in service standards despite financial investment. Exploring social or other underlying determinants

  7. Non-standard work schedules, gender, and parental stress

    Directory of Open Access Journals (Sweden)

    Mariona Lozano

    2016-02-01

    Full Text Available Background: Working non-standard hours changes the temporal structure of family life, constraining the time that family members spend with one another and threatening individuals' well-being. However, the empirical research on the link between stress and non-standard schedules has provided mixed results. Some studies have indicated that working non-standard hours is harmful whereas others have suggested that working atypical hours might facilitate the balance between family and work. Moreover, there is some evidence that the association between stress and non-standard employment has different implications for men and women. Objective: This paper examines the association between non-standard work schedules and stress among dual-earner couples with children. Two research questions are addressed. First, do predictability of the schedule and time flexibility moderate the link between non-standard work hours and stress? Second, do non-standard schedules affect men's and women's perceptions of stress differently? Methods: We use a sample of 1,932 working parents from the Canadian 2010 General Social Survey, which includes a time-use diary. A sequential logit regression analysis stratified by gender is employed to model two types of result. First, we estimate the odds of being stressed versus not being stressed. Second, for all respondents feeling stressed, we estimate the odds of experiencing high levels versus moderate levels of stress. Results: Our analysis shows that the link between non-standard working hours and perceived stress differs between mothers and fathers. First, fathers with non-standard schedules appear more likely to experience stress than those working standard hours, although the results are not significant. Among mothers, having a non-standard schedule is associated with a significantly lower risk of experiencing stress. Second, the analysis focusing on the mediating role of flexibility and predictability indicates that

  8. Noise-induced modulation of the relaxation kinetics around a non-equilibrium steady state of non-linear chemical reaction networks.

    Science.gov (United States)

    Ramaswamy, Rajesh; Sbalzarini, Ivo F; González-Segredo, Nélido

    2011-01-28

    Stochastic effects from correlated noise non-trivially modulate the kinetics of non-linear chemical reaction networks. This is especially important in systems where reactions are confined to small volumes and reactants are delivered in bursts. We characterise how the two noise sources confinement and burst modulate the relaxation kinetics of a non-linear reaction network around a non-equilibrium steady state. We find that the lifetimes of species change with burst input and confinement. Confinement increases the lifetimes of all species that are involved in any non-linear reaction as a reactant. Burst monotonically increases or decreases lifetimes. Competition between burst-induced and confinement-induced modulation may hence lead to a non-monotonic modulation. We quantify lifetime as the integral of the time autocorrelation function (ACF) of concentration fluctuations around a non-equilibrium steady state of the reaction network. Furthermore, we look at the first and second derivatives of the ACF, each of which is affected in opposite ways by burst and confinement. This allows discriminating between these two noise sources. We analytically derive the ACF from the linear Fokker-Planck approximation of the chemical master equation in order to establish a baseline for the burst-induced modulation at low confinement. Effects of higher confinement are then studied using a partial-propensity stochastic simulation algorithm. The results presented here may help understand the mechanisms that deviate stochastic kinetics from its deterministic counterpart. In addition, they may be instrumental when using fluorescence-lifetime imaging microscopy (FLIM) or fluorescence-correlation spectroscopy (FCS) to measure confinement and burst in systems with known reaction rates, or, alternatively, to correct for the effects of confinement and burst when experimentally measuring reaction rates.

  9. A feedback control strategy for the airfoil system under non-Gaussian colored noise excitation

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yong, E-mail: hy@njust.edu.cn, E-mail: taogang@njust.edu.cn; Tao, Gang, E-mail: hy@njust.edu.cn, E-mail: taogang@njust.edu.cn [School of Energy and Power Engineering, Nanjing University of Science and Technology, 200 XiaoLingwei Street, Nanjing 210094 (China)

    2014-09-01

    The stability of a binary airfoil with feedback control under stochastic disturbances, a non-Gaussian colored noise, is studied in this paper. First, based on some approximated theories and methods the non-Gaussian colored noise is simplified to an Ornstein-Uhlenbeck process. Furthermore, via the stochastic averaging method and the logarithmic polar transformation, one dimensional diffusion process can be obtained. At last by applying the boundary conditions, the largest Lyapunov exponent which can determine the almost-sure stability of the system and the effective region of control parameters is calculated.

  10. A feedback control strategy for the airfoil system under non-Gaussian colored noise excitation.

    Science.gov (United States)

    Huang, Yong; Tao, Gang

    2014-09-01

    The stability of a binary airfoil with feedback control under stochastic disturbances, a non-Gaussian colored noise, is studied in this paper. First, based on some approximated theories and methods the non-Gaussian colored noise is simplified to an Ornstein-Uhlenbeck process. Furthermore, via the stochastic averaging method and the logarithmic polar transformation, one dimensional diffusion process can be obtained. At last by applying the boundary conditions, the largest Lyapunov exponent which can determine the almost-sure stability of the system and the effective region of control parameters is calculated.

  11. Phonic Attenuation due to Screen-Barriers

    Directory of Open Access Journals (Sweden)

    Vasile Bacria

    2011-10-01

    Full Text Available The technique of noise decreasing admits two basic approaches: an active approach and a passive one. In the frame of passive method one can count the employment of screen-barriers. In this paper we present some considerations on sound attenuation due to screen-barriers emphasizing the elements which influence it. The elucidation of these elements is made by measurements. The obtained results can be applied in every other practical situation concerning the protection against noise.

  12. Non-auditory effects of noise in industry. V. A field study in a shipyard

    NARCIS (Netherlands)

    van Dijk, F. J.; Verbeek, J. H.; de Fries, F. F.

    1987-01-01

    Workers of a shipbuilding and a machine shop department of a shipyard, with average noise levels of 98 dB(A) and 85.5 dB(A) respectively, were compared with respect to auditory and non-auditory effects. The distribution of years of noise exposure and of age was similar in both departments. No

  13. Suppression of thermal noise in a non-Markovian random velocity field

    International Nuclear Information System (INIS)

    Ueda, Masahiko

    2016-01-01

    We study the diffusion of Brownian particles in a Gaussian random velocity field with short memory. By extending the derivation of an effective Fokker–Planck equation for the Lanvegin equation with weakly colored noise to a random velocity-field problem, we find that the effect of thermal noise on particles is suppressed by the existence of memory. We also find that the renormalization effect for the relative diffusion of two particles is stronger than that for single-particle diffusion. The results are compared with those of molecular dynamics simulations. (paper: classical statistical mechanics, equilibrium and non-equilibrium)

  14. Random noise attenuation of non-uniformly sampled 3D seismic data along two spatial coordinates using non-equispaced curvelet transform

    Science.gov (United States)

    Zhang, Hua; Yang, Hui; Li, Hongxing; Huang, Guangnan; Ding, Zheyi

    2018-04-01

    The attenuation of random noise is important for improving the signal to noise ratio (SNR). However, the precondition for most conventional denoising methods is that the noisy data must be sampled on a uniform grid, making the conventional methods unsuitable for non-uniformly sampled data. In this paper, a denoising method capable of regularizing the noisy data from a non-uniform grid to a specified uniform grid is proposed. Firstly, the denoising method is performed for every time slice extracted from the 3D noisy data along the source and receiver directions, then the 2D non-equispaced fast Fourier transform (NFFT) is introduced in the conventional fast discrete curvelet transform (FDCT). The non-equispaced fast discrete curvelet transform (NFDCT) can be achieved based on the regularized inversion of an operator that links the uniformly sampled curvelet coefficients to the non-uniformly sampled noisy data. The uniform curvelet coefficients can be calculated by using the inversion algorithm of the spectral projected-gradient for ℓ1-norm problems. Then local threshold factors are chosen for the uniform curvelet coefficients for each decomposition scale, and effective curvelet coefficients are obtained respectively for each scale. Finally, the conventional inverse FDCT is applied to the effective curvelet coefficients. This completes the proposed 3D denoising method using the non-equispaced curvelet transform in the source-receiver domain. The examples for synthetic data and real data reveal the effectiveness of the proposed approach in applications to noise attenuation for non-uniformly sampled data compared with the conventional FDCT method and wavelet transformation.

  15. Noise-induced modulation of the relaxation kinetics around a non-equilibrium steady state of non-linear chemical reaction networks.

    Directory of Open Access Journals (Sweden)

    Rajesh Ramaswamy

    2011-01-01

    Full Text Available Stochastic effects from correlated noise non-trivially modulate the kinetics of non-linear chemical reaction networks. This is especially important in systems where reactions are confined to small volumes and reactants are delivered in bursts. We characterise how the two noise sources confinement and burst modulate the relaxation kinetics of a non-linear reaction network around a non-equilibrium steady state. We find that the lifetimes of species change with burst input and confinement. Confinement increases the lifetimes of all species that are involved in any non-linear reaction as a reactant. Burst monotonically increases or decreases lifetimes. Competition between burst-induced and confinement-induced modulation may hence lead to a non-monotonic modulation. We quantify lifetime as the integral of the time autocorrelation function (ACF of concentration fluctuations around a non-equilibrium steady state of the reaction network. Furthermore, we look at the first and second derivatives of the ACF, each of which is affected in opposite ways by burst and confinement. This allows discriminating between these two noise sources. We analytically derive the ACF from the linear Fokker-Planck approximation of the chemical master equation in order to establish a baseline for the burst-induced modulation at low confinement. Effects of higher confinement are then studied using a partial-propensity stochastic simulation algorithm. The results presented here may help understand the mechanisms that deviate stochastic kinetics from its deterministic counterpart. In addition, they may be instrumental when using fluorescence-lifetime imaging microscopy (FLIM or fluorescence-correlation spectroscopy (FCS to measure confinement and burst in systems with known reaction rates, or, alternatively, to correct for the effects of confinement and burst when experimentally measuring reaction rates.

  16. How much does language proficiency by non-native listeners influence speech audiometric tests in noise?

    Science.gov (United States)

    Warzybok, Anna; Brand, Thomas; Wagener, Kirsten C; Kollmeier, Birger

    2015-01-01

    The current study investigates the extent to which the linguistic complexity of three commonly employed speech recognition tests and second language proficiency influence speech recognition thresholds (SRTs) in noise in non-native listeners. SRTs were measured for non-natives and natives using three German speech recognition tests: the digit triplet test (DTT), the Oldenburg sentence test (OLSA), and the Göttingen sentence test (GÖSA). Sixty-four non-native and eight native listeners participated. Non-natives can show native-like SRTs in noise only for the linguistically easy speech material (DTT). Furthermore, the limitation of phonemic-acoustical cues in digit triplets affects speech recognition to the same extent in non-natives and natives. For more complex and less familiar speech materials, non-natives, ranging from basic to advanced proficiency in German, require on average 3-dB better signal-to-noise ratio for the OLSA and 6-dB for the GÖSA to obtain 50% speech recognition compared to native listeners. In clinical audiology, SRT measurements with a closed-set speech test (i.e. DTT for screening or OLSA test for clinical purposes) should be used with non-native listeners rather than open-set speech tests (such as the GÖSA or HINT), especially if a closed-set version in the patient's own native language is available.

  17. White noise excited non-ideal elasto-plastic oscillator

    DEFF Research Database (Denmark)

    Ditlevsen, Ove Dalager; Tarp-Johansen, Niels Jacob

    1997-01-01

    Two sets of 50 samples of the displacement response of the top traverse relative to the second traverse of an experimental shear frame with three traverses subject to white noise base shaking of two different intensities have been recorded at Institut fur Allgemeine Mechanik in 1995, and are in f......Two sets of 50 samples of the displacement response of the top traverse relative to the second traverse of an experimental shear frame with three traverses subject to white noise base shaking of two different intensities have been recorded at Institut fur Allgemeine Mechanik in 1995......, and are in file available for analysis. The column connection between the two top traverses were made of aluminum with a linear-elastic non-ideal plastic behavior, and the columns were therefore renewed after each experiment. The two other connections were made of steel with a purely linear-elastic behavior...... on an oscillator of more than one degree of freedom. Applied to the experimental frame the calculations give excellent predictions of the main distributional properties of the plastic displacement process....

  18. Fitness Effects of Network Non-Linearity Induced by Gene Expression Noise

    Science.gov (United States)

    Ray, Christian; Cooper, Tim; Balazsi, Gabor

    2012-02-01

    In the non-equilibrium dynamics of growing microbial cells, metabolic enzymes can create non-linearities in metabolite concentration because of non-linear degradation (utilization): an enzyme can saturate in the process of metabolite utilization. Increasing metabolite production past the saturation point then results in an ultrasensitive metabolite response. If the production rate of a metabolite depends on a second enzyme or other protein-mediated process, uncorrelated gene expression noise can thus cause transient metabolite concentration bursts. Such bursts are physiologically unnecessary and may represent a source of selection against the ultrasensitive switch, especially if the fluctuating metabolic intermediate is toxic. Selection may therefore favor correlated gene expression fluctuations for enzymes in the same pathway, such as by same-operon membership in bacteria. Using a modified experimental lac operon system, we are undertaking a combined theoretical-experimental approach to demonstrate that (i) the lac operon has an implicit ultrasensitive switch that we predict is avoided by gene expression correlations induced by same-operon membership; (ii) bacterial growth rates are sensitive to crossing the ultrasensitive threshold. Our results suggest that correlations in intrinsic gene expression noise are exploited by evolution to ameliorate the detrimental effects of nonlinearities in metabolite concentrations.

  19. Non-symmetric forms of non-linear vibrations of flexible cylindrical panels and plates under longitudinal load and additive white noise

    Science.gov (United States)

    Krysko, V. A.; Awrejcewicz, J.; Krylova, E. Yu; Papkova, I. V.; Krysko, A. V.

    2018-06-01

    Parametric non-linear vibrations of flexible cylindrical panels subjected to additive white noise are studied. The governing Marguerre equations are investigated using the finite difference method (FDM) of the second-order accuracy and the Runge-Kutta method. The considered mechanical structural member is treated as a system of many/infinite number of degrees of freedom (DoF). The dependence of chaotic vibrations on the number of DoFs is investigated. Reliability of results is guaranteed by comparing the results obtained using two qualitatively different methods to reduce the problem of PDEs (partial differential equations) to ODEs (ordinary differential equations), i.e. the Faedo-Galerkin method in higher approximations and the 4th and 6th order FDM. The Cauchy problem obtained by the FDM is eventually solved using the 4th-order Runge-Kutta methods. The numerical experiment yielded, for a certain set of parameters, the non-symmetric vibration modes/forms with and without white noise. In particular, it has been illustrated and discussed that action of white noise on chaotic vibrations implies quasi-periodicity, whereas the previously non-symmetric vibration modes are closer to symmetric ones.

  20. Combining semantics with non-standard interpreter hierarchies

    DEFF Research Database (Denmark)

    Abramov, Sergei M.; Glück, Robert

    2000-01-01

    This paper reports on results concerning the combination of non-standard semantics via interpreters. We define what a semantics combination means and identify under which conditions a combination can be realized by computer programs (robustness, safely combinable). We develop the underlying mathe...... mathematical theory and examine the meaning of several non-standard interpreter towers. Our results suggest a technique for the implementation of a certain class of programming language dialects by composing a hierarchy of non-standard interpreters....

  1. Study of quantum noise in nanoscale devices via the de Broglie-Bohm formulation

    International Nuclear Information System (INIS)

    Oriols, X.

    2005-01-01

    Full text: The experimental current measured in quantum-based devices fluctuates around average values, even at static conditions. Such current fluctuations are a consequence of the wave-particle duality. Roughly speaking, the undulatory nature of electrons (Schroedinger equation) controls the average current, while the particle like (discrete) nature of electrons determines the fluctuations. Such randomness in the electron flux of mesoscopic systems is known as quantum noise. The de Broglie-Bohm (dBB) interpretation of the quantum theory provides an excellent framework to study quantum noise because it describes phase-coherent phenomena in terms of well-defined quantum trajectories. This theory was initiated by de Broglie in 1926 and fully clarified by Bohm in 1952. In this conference we will present our quantum transport formalism, based on the dBB theory, to study fluctuations in mesoscopic systems. First, we show the excellent agreement between our noise results and those obtained by other approaches for simple tunnelling system. In addition, we will show how our quantum noise approach can directly include the non-trivial many-particle Coulomb interaction among electrons, via the instantaneous self-consistent solution of the Poisson and the Schroedinger equations. As a test, we study standard resonant tunnelling diodes for double and triple barrier. The current fluctuations obtained with dBB theory are in complete agreement with experimental results. We will also present noise results for time-dependent scenarios driven by very high frequencies (few THz), which are comparable to the inverse of the electron transit time in nanoscale devices. Under such conditions, the tunnelling phenomenology is clearly enriched leading to experimental evidences for the dBB theory. (author)

  2. Shot noise enhancement from non-equilibrium plasmons in Luttinger liquid junctions

    International Nuclear Information System (INIS)

    Kim, Jaeuk U; Kinaret, Jari M; Choi, Mahn-Soo

    2005-01-01

    We consider a quantum wire double junction system with each wire segment described by a spinless Luttinger model, and study theoretically shot noise in this system in the sequential tunnelling regime. We find that the non-equilibrium plasmonic excitations in the central wire segment give rise to qualitatively different behaviour compared to the case with equilibrium plasmons. In particular, shot noise is greatly enhanced by them, and exceeds the Poisson limit. We show that the enhancement can be explained by the emergence of several current-carrying processes, and that the effect disappears if the channels effectively collapse to one because of fast plasmon relaxation processes, for example

  3. Investigating the influence on safety of retrofitting Italian motorways with barriers meeting a new EU standard.

    Science.gov (United States)

    Cafiso, Salvatore; D'Agostino, Carmelo; Persaud, Bhagwant

    2017-04-03

    A new European Union (EU) regulation for safety barriers, which is based on performance, has encouraged road agencies to perform an upgrade of old barriers, with the expectation that there will be safety benefits at the retrofitted sites. The new class of barriers was designed and installed in compliance with the 1998 (European Norm) EN 1317 standards for road restraint systems, which lays down common requirements for the testing and certification of road restraint systems in all countries of the European Committee for Standardization (CEN). Both the older and new barriers are made of steel and are installed in such a way as to avoid vehicle intrusion, but the older ones are thought to be only effective at low speeds and large angles of impact. The new standard seeks to remedy this by providing better protection at higher speeds. This article seeks to quantify the effect on the frequency of fatal and injury crashes of retrofitting motorways with barriers meeting the new standards. The estimation of the crash modification was carried out by performing an empirical Bayes before-after analysis based on data from the A18 Messina-Catania motorway in Italy. The methodology has the great advantage to account for the regression to the mean effects. Besides, to account for time trend effects and dispersion of crash data, a modified calibration methodology of safety performance was used. This study, based on data collected on 76 km of motorway in the period 2000-2012, derived Crash Modification Factor point estimates that indicate reductions of 72% for run-off-road fatal and injury crashes and 38% in total fatal and injury crashes that could be expected by upgrading an old safety barrier by complying with new EU 1317 standards. The estimated benefit-cost ratio of 5.57 for total crashes indicates that the treatment is cost effective. The magnitude of this benefit indicates that the retrofits are cost-effective even for total crashes and should continue in any European country

  4. Conditional Probabilities in the Excursion Set Theory. Generic Barriers and non-Gaussian Initial Conditions

    CERN Document Server

    De Simone, Andrea; Riotto, Antonio

    2011-01-01

    The excursion set theory, where density perturbations evolve stochastically with the smoothing scale, provides a method for computing the dark matter halo mass function. The computation of the mass function is mapped into the so-called first-passage time problem in the presence of a moving barrier. The excursion set theory is also a powerful formalism to study other properties of dark matter halos such as halo bias, accretion rate, formation time, merging rate and the formation history of halos. This is achieved by computing conditional probabilities with non-trivial initial conditions, and the conditional two-barrier first-crossing rate. In this paper we use the recently-developed path integral formulation of the excursion set theory to calculate analytically these conditional probabilities in the presence of a generic moving barrier, including the one describing the ellipsoidal collapse, and for both Gaussian and non-Gaussian initial conditions. The non-Markovianity of the random walks induced by non-Gaussi...

  5. Activated barrier crossing dynamics in the non-radiative decay of NADH and NADPH

    Energy Technology Data Exchange (ETDEWEB)

    Blacker, Thomas S., E-mail: t.blacker@ucl.ac.uk [Centre for Mathematics and Physics in the Life Sciences and Experimental Biology (CoMPLEX), University College London, London WC1E 6BT (United Kingdom); Department of Physics and Astronomy, University College London, London WC1E 6BT (United Kingdom); Research Department of Cell and Developmental Biology, University College London, London WC1E 6BT (United Kingdom); Marsh, Richard J., E-mail: richard.marsh@ucl.ac.uk [Department of Physics and Astronomy, University College London, London WC1E 6BT (United Kingdom); Duchen, Michael R., E-mail: m.duchen@ucl.ac.uk [Research Department of Cell and Developmental Biology, University College London, London WC1E 6BT (United Kingdom); Bain, Angus J., E-mail: a.bain@ucl.ac.uk [Centre for Mathematics and Physics in the Life Sciences and Experimental Biology (CoMPLEX), University College London, London WC1E 6BT (United Kingdom); Department of Physics and Astronomy, University College London, London WC1E 6BT (United Kingdom)

    2013-08-30

    Highlights: ► NADH and NADPH have a high rate of non-radiative excited state decay. ► Conformational relaxation is shown to be a significant non-radiative pathway. ► The Kramers equation describes the barrier crossing dynamics of the relaxation. ► Conformational restriction upon enzyme binding will alter NAD(P)H lifetimes. - Abstract: In live tissue, alterations in metabolism induce changes in the fluorescence decay of the biological coenzyme NAD(P)H, the mechanism of which is not well understood. In this work, the fluorescence and anisotropy decay dynamics of NADH and NADPH were investigated as a function of viscosity in a range of water–glycerol solutions. The viscosity dependence of the non-radiative decay is well described by Kramers and Kramers–Hubbard models of activated barrier crossing over a wide viscosity range. Our combined lifetime and anisotropy analysis indicates common mechanisms of non-radiative relaxation in the two emitting states (conformations) of both molecules. The low frequencies associated with barrier crossing suggest that non-radiative decay is mediated by small scale motion (e.g. puckering) of the nicotinamide ring. Variations in the fluorescence lifetimes of NADH and NADPH when bound to different enzymes may therefore be attributed to differing levels of conformational restriction upon binding.

  6. Synthesizing qualitative and quantitative evidence on non-financial access barriers: implications for assessment at the district level.

    Science.gov (United States)

    O'Connell, Thomas S; Bedford, K Juliet A; Thiede, Michael; McIntyre, Di

    2015-06-09

    A key element of the global drive to universal health coverage is ensuring access to needed health services for everyone, and to pursue this goal in an equitable way. This requires concerted efforts to reduce disparities in access through understanding and acting on barriers facing communities with the lowest utilisation levels. Financial barriers dominate the empirical literature on health service access. Unless the full range of access barriers are investigated, efforts to promote equitable access to health care are unlikely to succeed. This paper therefore focuses on exploring the nature and extent of non-financial access barriers. We draw upon two structured literature reviews on barriers to access and utilization of maternal, newborn and child health services in Ghana, Bangladesh, Vietnam and Rwanda. One review analyses access barriers identified in published literature using qualitative research methods; the other in published literature using quantitative analysis of household survey data. We then synthesised the key qualitative and quantitative findings through a conjoint iterative analysis. Five dominant themes on non-financial access barriers were identified: ethnicity; religion; physical accessibility; decision-making, gender and autonomy; and knowledge, information and education. The analysis highlighted that non-financial factors pose considerable barriers to access, many of which relate to the acceptability dimension of access and are challenging to address. Another key finding is that quantitative research methods, while yielding important findings, are inadequate for understanding non-financial access barriers in sufficient detail to develop effective responses. Qualitative research is critical in filling this gap. The analysis also indicates that the nature of non-financial access barriers vary considerably, not only between countries but also between different communities within individual countries. To adequately understand access barriers as a

  7. Acceptable noise level (ANL) with Danish and non-semantic speech materials in adult hearing-aid users

    DEFF Research Database (Denmark)

    Olsen, Steen Østergaard; Lantz, Johannes; Nielsen, Lars Holme

    2012-01-01

    The acceptable noise level (ANL) test is used for quantification of the amount of background noise subjects accept when listening to speech. This study investigates Danish hearing-aid users' ANL performance using Danish and non-semantic speech signals, the repeatability of ANL, and the association...

  8. Perceptual effects of noise reduction by time-frequency masking of noisy speech.

    Science.gov (United States)

    Brons, Inge; Houben, Rolph; Dreschler, Wouter A

    2012-10-01

    Time-frequency masking is a method for noise reduction that is based on the time-frequency representation of a speech in noise signal. Depending on the estimated signal-to-noise ratio (SNR), each time-frequency unit is either attenuated or not. A special type of a time-frequency mask is the ideal binary mask (IBM), which has access to the real SNR (ideal). The IBM either retains or removes each time-frequency unit (binary mask). The IBM provides large improvements in speech intelligibility and is a valuable tool for investigating how different factors influence intelligibility. This study extends the standard outcome measure (speech intelligibility) with additional perceptual measures relevant for noise reduction: listening effort, noise annoyance, speech naturalness, and overall preference. Four types of time-frequency masking were evaluated: the original IBM, a tempered version of the IBM (called ITM) which applies limited and non-binary attenuation, and non-ideal masking (also tempered) with two different types of noise-estimation algorithms. The results from ideal masking imply that there is a trade-off between intelligibility and sound quality, which depends on the attenuation strength. Additionally, the results for non-ideal masking suggest that subjective measures can show effects of noise reduction even if noise reduction does not lead to differences in intelligibility.

  9. Parallel logic gates in synthetic gene networks induced by non-Gaussian noise.

    Science.gov (United States)

    Xu, Yong; Jin, Xiaoqin; Zhang, Huiqing

    2013-11-01

    The recent idea of logical stochastic resonance is verified in synthetic gene networks induced by non-Gaussian noise. We realize the switching between two kinds of logic gates under optimal moderate noise intensity by varying two different tunable parameters in a single gene network. Furthermore, in order to obtain more logic operations, thus providing additional information processing capacity, we obtain in a two-dimensional toggle switch model two complementary logic gates and realize the transformation between two logic gates via the methods of changing different parameters. These simulated results contribute to improve the computational power and functionality of the networks.

  10. Recent progress in the field of non-auditory health effects of noise. Trends and research needs

    NARCIS (Netherlands)

    Kluizenaar, Y. de; Matsui, T.

    2017-01-01

    With the aim to identify recent research achievements, current trends in research, remaining gaps of knowledge and priority areas of future research in the field of non-auditory health effects of noise, recent research progress was reviewed. A search was performed in PubMed (search terms “noise AND

  11. Extinction Effects of Multiplicative Non-Gaussian Lévy Noise in a Tumor Growth System with Immunization

    International Nuclear Information System (INIS)

    Hao Meng-Li; Xu Wei; Liu Di; Li Dong-Xi

    2014-01-01

    The extinction phenomenon induced by multiplicative non-Gaussian Lévy noise in a tumor growth model with immune response is discussed. Under the influence of the stochastic immune rate, the model is analyzed in terms of a stochastic differential equation with multiplicative noise. By means of the theory of the infinitesimal generator of Hunt processes, the escape probability, which is used to measure the noise-induced extinction probability of tumor cells, is explicitly expressed as a function of initial tumor cell density, stability index and noise intensity. Based on the numerical calculations, it is found that for different initial densities of tumor cells, noise parameters play opposite roles on the escape probability. The optimally selected values of the multiplicative noise intensity and the stability index are found to maximize the escape probability. (general)

  12. Non-Saccharomyces yeasts protect against epithelial cell barrier disruption induced by Salmonella enterica subsp. enterica serovar Typhimurium

    DEFF Research Database (Denmark)

    Smith, Ida Mosbech; Baker, A; Arneborg, Nils

    2015-01-01

    distinct patterns of non-Saccharomyces yeast modulation of epithelial cell barrier function. While the established probiotic yeast Saccharomyces boulardii increased TER across a Caco-2 monolayer by 30%, Kluyveromyces marxianus exhibited significantly stronger properties of TER enhancement (50% TER increase....... In addition, probiotic strains may be able to reduce epithelial barrier disruption caused by pathogenic species. The aim of this study was to explore non-Saccharomyces yeast modulation of epithelial cell barrier function in vitro. Benchmarking against established probiotic strains, we evaluated the ability......). In addition, our data demonstrate significant yeast-mediated modulation of Salmonella-induced epithelial cell barrier disruption and identify K. marxianus and Metschnikowia gruessii as two non-Saccharomyces yeasts capable of protecting human epithelial cells from pathogen invasion. SIGNIFICANCE AND IMPACT...

  13. Facilitators and barriers to non-medical prescribing - A systematic review and thematic synthesis.

    Science.gov (United States)

    Graham-Clarke, Emma; Rushton, Alison; Noblet, Timothy; Marriott, John

    2018-01-01

    Non-medical prescribing has the potential to deliver innovative healthcare within limited finances. However, uptake has been slow, and a proportion of non-medical prescribers do not use the qualification. This systematic review aimed to describe the facilitators and barriers to non-medical prescribing in the United Kingdom. The systematic review and thematic analysis included qualitative and mixed methods papers reporting facilitators and barriers to independent non-medical prescribing in the United Kingdom. The following databases were searched to identify relevant papers: AMED, ASSIA, BNI, CINAHL, EMBASE, ERIC, MEDLINE, Open Grey, Open access theses and dissertations, and Web of Science. Papers published between 2006 and March 2017 were included. Studies were quality assessed using a validated tool (QATSDD), then underwent thematic analysis. The protocol was registered with PROSPERO (CRD42015019786). Of 3991 potentially relevant identified studies, 42 were eligible for inclusion. The studies were generally of moderate quality (83%), and most (71%) were published 2007-2012. The nursing profession dominated the studies (30/42). Thematic analysis identified three overarching themes: non-medical prescriber, human factors, and organisational aspects. Each theme consisted of several sub-themes; the four most highly mentioned were 'medical professionals', 'area of competence', 'impact on time' and 'service'. Sub-themes were frequently interdependent on each other, having the potential to act as a barrier or facilitator depending on circumstances. Addressing the identified themes and subthemes enables strategies to be developed to support and optimise non-medical prescribing. Further research is required to identify if similar themes are encountered by other non-medical prescribing groups than nurses and pharmacists.

  14. On-board sound intensity tire-pavement noise study in North Carolina.

    Science.gov (United States)

    2011-12-01

    "This research investigated tire-pavement noise on various types of pavements across North Carolina by using On- : Board Sound Intensity (OBSI) method. To mitigate traffic noise, quieter pavement may provide advantages that : noise barriers cannot. T...

  15. Transient Properties of a Bistable System with Delay Time Driven by Non-Gaussian and Gaussian Noises: Mean First-Passage Time

    International Nuclear Information System (INIS)

    Li Dongxi; Xu Wei; Guo Yongfeng; Li Gaojie

    2008-01-01

    The mean first-passage time of a bistable system with time-delayed feedback driven by multiplicative non-Gaussian noise and additive Gaussian white noise is investigated. Firstly, the non-Markov process is reduced to the Markov process through a path-integral approach; Secondly, the approximate Fokker-Planck equation is obtained by applying the unified coloured noise approximation, the small time delay approximation and the Novikov Theorem. The functional analysis and simplification are employed to obtain the approximate expressions of MFPT. The effects of non-Gaussian parameter (measures deviation from Gaussian character) r, the delay time τ, the noise correlation time τ 0 , the intensities D and α of noise on the MFPT are discussed. It is found that the escape time could be reduced by increasing the delay time τ, the noise correlation time τ 0 , or by reducing the intensities D and α. As far as we know, this is the first time to consider the effect of delay time on the mean first-passage time in the stochastic dynamical system

  16. Decoherence and tripartite entanglement dynamics in the presence of Gaussian and non-Gaussian classical noise

    Energy Technology Data Exchange (ETDEWEB)

    Kenfack, Lionel Tenemeza, E-mail: kenfacklionel300@gmail.com [Mesoscopic and Multilayer Structure Laboratory, Department of Physics, Faculty of Science, University of Dschang, PO Box: 67 Dschang (Cameroon); Tchoffo, Martin; Fai, Lukong Cornelius [Mesoscopic and Multilayer Structure Laboratory, Department of Physics, Faculty of Science, University of Dschang, PO Box: 67 Dschang (Cameroon); Fouokeng, Georges Collince [Mesoscopic and Multilayer Structure Laboratory, Department of Physics, Faculty of Science, University of Dschang, PO Box: 67 Dschang (Cameroon); Laboratoire de Génie des Matériaux, Pôle Recherche-Innovation-Entrepreneuriat (PRIE), Institut Universitaire de la Côte, BP 3001 Douala (Cameroon)

    2017-04-15

    We address the entanglement dynamics of a three-qubit system interacting with a classical fluctuating environment described either by a Gaussian or non-Gaussian noise in three different configurations namely: common, independent and mixed environments. Specifically, we focus on the Ornstein-Uhlenbeck (OU) noise and the random telegraph noise (RTN). The qubits are prepared in a state composed of a Greenberger-Horne-Zeilinger (GHZ) and a W state. With the help of the tripartite negativity, we show that the entanglement evolution is not only affected by the type of system-environment coupling but also by the kind and the memory properties of the considered noise. We also compared the dynamics induced by the two kinds of noise and we find that even if both noises have a Lorentzian spectrum, the effects of the OU noise cannot be in a simple way deduced from those of the RTN and vice-versa. In addition, we show that the entanglement can be indefinitely preserved when the qubits are coupled to the environmental noise in a common environment (CE). Finally, the presence or absence of peculiar phenomena such as entanglement revivals (ER) and entanglement sudden death (ESD) is observed.

  17. Decoherence and tripartite entanglement dynamics in the presence of Gaussian and non-Gaussian classical noise

    International Nuclear Information System (INIS)

    Kenfack, Lionel Tenemeza; Tchoffo, Martin; Fai, Lukong Cornelius; Fouokeng, Georges Collince

    2017-01-01

    We address the entanglement dynamics of a three-qubit system interacting with a classical fluctuating environment described either by a Gaussian or non-Gaussian noise in three different configurations namely: common, independent and mixed environments. Specifically, we focus on the Ornstein-Uhlenbeck (OU) noise and the random telegraph noise (RTN). The qubits are prepared in a state composed of a Greenberger-Horne-Zeilinger (GHZ) and a W state. With the help of the tripartite negativity, we show that the entanglement evolution is not only affected by the type of system-environment coupling but also by the kind and the memory properties of the considered noise. We also compared the dynamics induced by the two kinds of noise and we find that even if both noises have a Lorentzian spectrum, the effects of the OU noise cannot be in a simple way deduced from those of the RTN and vice-versa. In addition, we show that the entanglement can be indefinitely preserved when the qubits are coupled to the environmental noise in a common environment (CE). Finally, the presence or absence of peculiar phenomena such as entanglement revivals (ER) and entanglement sudden death (ESD) is observed.

  18. In vivo validation of cardiac output assessment in non-standard 3D echocardiographic images

    Energy Technology Data Exchange (ETDEWEB)

    Nillesen, M M; Lopata, R G P; Gerrits, I H; Thijssen, J M; De Korte, C L [Clinical Physics Laboratory-833, Department of Pediatrics, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); De Boode, W P [Neonatology, Department of Pediatrics, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Huisman, H J [Department of Radiology, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands); Kapusta, L [Pediatric Cardiology, Department of Pediatrics, Radboud University Nijmegen Medical Centre, Nijmegen (Netherlands)], E-mail: m.m.nillesen@cukz.umcn.nl

    2009-04-07

    Automatic segmentation of the endocardial surface in three-dimensional (3D) echocardiographic images is an important tool to assess left ventricular (LV) geometry and cardiac output (CO). The presence of speckle noise as well as the nonisotropic characteristics of the myocardium impose strong demands on the segmentation algorithm. In the analysis of normal heart geometries of standardized (apical) views, it is advantageous to incorporate a priori knowledge about the shape and appearance of the heart. In contrast, when analyzing abnormal heart geometries, for example in children with congenital malformations, this a priori knowledge about the shape and anatomy of the LV might induce erroneous segmentation results. This study describes a fully automated segmentation method for the analysis of non-standard echocardiographic images, without making strong assumptions on the shape and appearance of the heart. The method was validated in vivo in a piglet model. Real-time 3D echocardiographic image sequences of five piglets were acquired in radiofrequency (rf) format. These ECG-gated full volume images were acquired intra-operatively in a non-standard view. Cardiac blood flow was measured simultaneously by an ultrasound transit time flow probe positioned around the common pulmonary artery. Three-dimensional adaptive filtering using the characteristics of speckle was performed on the demodulated rf data to reduce the influence of speckle noise and to optimize the distinction between blood and myocardium. A gradient-based 3D deformable simplex mesh was then used to segment the endocardial surface. A gradient and a speed force were included as external forces of the model. To balance data fitting and mesh regularity, one fixed set of weighting parameters of internal, gradient and speed forces was used for all data sets. End-diastolic and end-systolic volumes were computed from the segmented endocardial surface. The cardiac output derived from this automatic segmentation was

  19. In vivo validation of cardiac output assessment in non-standard 3D echocardiographic images

    International Nuclear Information System (INIS)

    Nillesen, M M; Lopata, R G P; Gerrits, I H; Thijssen, J M; De Korte, C L; De Boode, W P; Huisman, H J; Kapusta, L

    2009-01-01

    Automatic segmentation of the endocardial surface in three-dimensional (3D) echocardiographic images is an important tool to assess left ventricular (LV) geometry and cardiac output (CO). The presence of speckle noise as well as the nonisotropic characteristics of the myocardium impose strong demands on the segmentation algorithm. In the analysis of normal heart geometries of standardized (apical) views, it is advantageous to incorporate a priori knowledge about the shape and appearance of the heart. In contrast, when analyzing abnormal heart geometries, for example in children with congenital malformations, this a priori knowledge about the shape and anatomy of the LV might induce erroneous segmentation results. This study describes a fully automated segmentation method for the analysis of non-standard echocardiographic images, without making strong assumptions on the shape and appearance of the heart. The method was validated in vivo in a piglet model. Real-time 3D echocardiographic image sequences of five piglets were acquired in radiofrequency (rf) format. These ECG-gated full volume images were acquired intra-operatively in a non-standard view. Cardiac blood flow was measured simultaneously by an ultrasound transit time flow probe positioned around the common pulmonary artery. Three-dimensional adaptive filtering using the characteristics of speckle was performed on the demodulated rf data to reduce the influence of speckle noise and to optimize the distinction between blood and myocardium. A gradient-based 3D deformable simplex mesh was then used to segment the endocardial surface. A gradient and a speed force were included as external forces of the model. To balance data fitting and mesh regularity, one fixed set of weighting parameters of internal, gradient and speed forces was used for all data sets. End-diastolic and end-systolic volumes were computed from the segmented endocardial surface. The cardiac output derived from this automatic segmentation was

  20. In vivo validation of cardiac output assessment in non-standard 3D echocardiographic images

    Science.gov (United States)

    Nillesen, M. M.; Lopata, R. G. P.; de Boode, W. P.; Gerrits, I. H.; Huisman, H. J.; Thijssen, J. M.; Kapusta, L.; de Korte, C. L.

    2009-04-01

    Automatic segmentation of the endocardial surface in three-dimensional (3D) echocardiographic images is an important tool to assess left ventricular (LV) geometry and cardiac output (CO). The presence of speckle noise as well as the nonisotropic characteristics of the myocardium impose strong demands on the segmentation algorithm. In the analysis of normal heart geometries of standardized (apical) views, it is advantageous to incorporate a priori knowledge about the shape and appearance of the heart. In contrast, when analyzing abnormal heart geometries, for example in children with congenital malformations, this a priori knowledge about the shape and anatomy of the LV might induce erroneous segmentation results. This study describes a fully automated segmentation method for the analysis of non-standard echocardiographic images, without making strong assumptions on the shape and appearance of the heart. The method was validated in vivo in a piglet model. Real-time 3D echocardiographic image sequences of five piglets were acquired in radiofrequency (rf) format. These ECG-gated full volume images were acquired intra-operatively in a non-standard view. Cardiac blood flow was measured simultaneously by an ultrasound transit time flow probe positioned around the common pulmonary artery. Three-dimensional adaptive filtering using the characteristics of speckle was performed on the demodulated rf data to reduce the influence of speckle noise and to optimize the distinction between blood and myocardium. A gradient-based 3D deformable simplex mesh was then used to segment the endocardial surface. A gradient and a speed force were included as external forces of the model. To balance data fitting and mesh regularity, one fixed set of weighting parameters of internal, gradient and speed forces was used for all data sets. End-diastolic and end-systolic volumes were computed from the segmented endocardial surface. The cardiac output derived from this automatic segmentation was

  1. Wigner functions on non-standard symplectic vector spaces

    Science.gov (United States)

    Dias, Nuno Costa; Prata, João Nuno

    2018-01-01

    We consider the Weyl quantization on a flat non-standard symplectic vector space. We focus mainly on the properties of the Wigner functions defined therein. In particular we show that the sets of Wigner functions on distinct symplectic spaces are different but have non-empty intersections. This extends previous results to arbitrary dimension and arbitrary (constant) symplectic structure. As a by-product we introduce and prove several concepts and results on non-standard symplectic spaces which generalize those on the standard symplectic space, namely, the symplectic spectrum, Williamson's theorem, and Narcowich-Wigner spectra. We also show how Wigner functions on non-standard symplectic spaces behave under the action of an arbitrary linear coordinate transformation.

  2. Improving Signal-to-Noise Ratio in Susceptibility Weighted Imaging: A Novel Multicomponent Non-Local Approach.

    Directory of Open Access Journals (Sweden)

    Pasquale Borrelli

    Full Text Available In susceptibility-weighted imaging (SWI, the high resolution required to obtain a proper contrast generation leads to a reduced signal-to-noise ratio (SNR. The application of a denoising filter to produce images with higher SNR and still preserve small structures from excessive blurring is therefore extremely desirable. However, as the distributions of magnitude and phase noise may introduce biases during image restoration, the application of a denoising filter is non-trivial. Taking advantage of the potential multispectral nature of MR images, a multicomponent approach using a Non-Local Means (MNLM denoising filter may perform better than a component-by-component image restoration method. Here we present a new MNLM-based method (Multicomponent-Imaginary-Real-SWI, hereafter MIR-SWI to produce SWI images with high SNR and improved conspicuity. Both qualitative and quantitative comparisons of MIR-SWI with the original SWI scheme and previously proposed SWI restoring pipelines showed that MIR-SWI fared consistently better than the other approaches. Noise removal with MIR-SWI also provided improvement in contrast-to-noise ratio (CNR and vessel conspicuity at higher factors of phase mask multiplications than the one suggested in the literature for SWI vessel imaging. We conclude that a proper handling of noise in the complex MR dataset may lead to improved image quality for SWI data.

  3. Non-Unitarity, sterile neutrinos, and Non-Standard neutrino Interactions

    CERN Document Server

    Blennow, Mattias; Fernandez-Martinez, Enrique; Hernandez-Garcia, Josu; Lopez-Pavon, Jacobo

    2017-04-27

    The simplest Standard Model extension to explain neutrino masses involves the addition of right-handed neutrinos. At some level, this extension will impact neutrino oscillation searches. In this work we explore the differences and similarities between the case in which these neutrinos are kinematically accessible (sterile neutrinos) or not (mixing matrix non-unitarity). We clarify apparent inconsistencies in the present literature when using different parametrizations to describe these effects and recast both limits in the popular neutrino non-standard interaction (NSI) formal- ism. We find that, in the limit in which sterile oscillations are averaged out at the near detector, their effects at the far detector coincide with non-unitarity at leading order, even in presence of a matter potential. We also summarize the present bounds existing in both limits and compare them with the expected sensitivities of near-future facilities taking the DUNE proposal as a bench- mark. We conclude that non-unitarity effects ...

  4. DOE Technical Standards List. Directory of DOE and contractor personnel involved in non-government standards activities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    This is a periodic report on the level of agency participation in non-Government standards activities. This technical standards list is intended to assist US Department of Energy (DOE) management and other personnel involved in the DOE technical Standards Program by identifying those participating individuals. The body of this document contains a listing of DOE employees and DOE contractors who have submitted a Record of Non-Government Standards Activity. Additional names were added from rosters supplied by non-Government standards bodies. Appendices to this document are provided to list the information by parent employment organization, by non-Government standards activity, and by the proper names of the non-Government standards organizations and committees.

  5. Localized, Non-Harmonic Active Flap Motions for Low Frequency In-Plane Rotor Noise Reduction

    Science.gov (United States)

    Sim, Ben W.; Potsdam, Mark; Kitaplioglu, Cahit; LeMasurier, Philip; Lorber, Peter; Andrews, Joseph

    2012-01-01

    A first-of-its-kind demonstration of the use of localized, non-harmonic active flap motions, for suppressing low frequency, in-plane rotor noise, is reported in this paper. Operational feasibility is verified via testing of the full-scale AATD/Sikorsky/UTRC active flap demonstration rotor in the NFAC's 40- by 80-Foot anechoic wind tunnel. Effectiveness of using localized, non-harmonic active flap motions are compared to conventional four-per-rev harmonic flap motions, and also active flap motions derived from closed-loop acoustics implementations. All three approaches resulted in approximately the same noise reductions over an in-plane three-by-three microphone array installed forward and near in-plane of the rotor in the nearfield. It is also reported that using an active flap in this localized, non-harmonic manner, resulted in no more that 2% rotor performance penalty, but had the tendency to incur higher hub vibration levels.

  6. Non_standard Wood

    DEFF Research Database (Denmark)

    Tamke, Martin

    . Using parametric design tools and computer controlled production facilities Copenhagens Centre for IT and Architecture undertook a practice based research into performance based non-standard element design and mass customization techniques. In close cooperation with wood construction software......, but the integration of traditional wood craft techniques. The extensive use of self adjusting, load bearing wood-wood joints contributed to ease in production and assembly of a performance based architecture....

  7. Noise and Vibration Mitigation for Rail Transportation Systems : Proceedings of the 10th International Workshop on RailwayNoise

    CERN Document Server

    Gautier, Pierre-Etienne; Hanson, Carl; Hemsworth, Brian; Nelson, James; Schulte-Werning, Burkhard; Thompson, David; Vos, Paul

    2012-01-01

    This volume contains the contributions to the 10th International Workshop on Railway Noise, held October 18–22, 2010, in Nagahama, Japan, organized by the Railway Technical Research Institute (RTRI), Japan. With 11 sessions and 3 poster sessions, the workshop featured presentations by international leaders in the field of railway noise and vibration. All subjects relating to 1. prospects, legal regulation, and perception; 2. wheel and rail noise; 3. structure-borne noise and squeal noise; 4. ground-borne vibration; 5. aerodynamic noise and micro-pressure waves from tunnel portals; 6. interior noise and sound barriers; and 7. prediction, measurements, and monitoring are addressed here. This book is a useful “state-of-the-art” reference for scientists and engineers involved in solving environmental problems of railways.

  8. [Criteria for the assessment of the noise-induced occupational hearing loss: international and national standards].

    Science.gov (United States)

    Izmerov, N F; Denisov, É I; Adeninskaia, E E; Gorblianskiĭ, Iu Iu

    2014-01-01

    The objective of the present paper was to review international and national standards for the criteria of assessment of the noise-induced occupational loss of hearing. The importance of healthy hearing for the occupational safety is emphasized which implies the necessity of the more rigorous criteria for hearing conservation in the workers engaged in the noisy technological environment compared with those for the general population. A rationale for the development of the standard program of hearing conservation in the workers engaged in the noisy technological environment is proposed including hygienic norms and rules or national state standards.

  9. Summary Report Panel 1: The Need for Protocols and Standards in Research on Underwater Noise Impacts on Marine Life.

    Science.gov (United States)

    Erbe, Christine; Ainslie, Michael A; de Jong, Christ A F; Racca, Roberto; Stocker, Michael

    2016-01-01

    As concern about anthropogenic noise and its impacts on marine fauna is increasing around the globe, data are being compared across populations, species, noise sources, geographic regions, and time. However, much of the raw and processed data are not comparable due to differences in measurement methodology, analysis and reporting, and a lack of metadata. Common protocols and more formal, international standards are needed to ensure the effectiveness of research, conservation, regulation and practice, and unambiguous communication of information and ideas. Developing standards takes time and effort, is largely driven by a few expert volunteers, and would benefit from stakeholders' contribution and support.

  10. Lifting primordial non-Gaussianity above the noise

    International Nuclear Information System (INIS)

    Welling, Yvette; Woude, Drian van der; Pajer, Enrico

    2016-01-01

    Primordial non-Gaussianity (PNG) in Large Scale Structures is obfuscated by the many additional sources of non-linearity. Within the Effective Field Theory approach to Standard Perturbation Theory, we show that matter non-linearities in the bispectrum can be modeled sufficiently well to strengthen current bounds with near future surveys, such as Euclid. We find that the EFT corrections are crucial to this improvement in sensitivity. Yet, our understanding of non-linearities is still insufficient to reach important theoretical benchmarks for equilateral PNG, while, for local PNG, our forecast is more optimistic. We consistently account for the theoretical error intrinsic to the perturbative approach and discuss the details of its implementation in Fisher forecasts.

  11. Effect of Dielectric Barrier Discharge Plasma Actuators on Non-equilibrium Hypersonic Flows

    Science.gov (United States)

    2014-10-28

    results for MIG with the US3D code devel- oped at the University of Minnesota.61 US3D is an unstruc- tured CFD code for hypersonic flow solution used...Effect of dielectric barrier discharge plasma actuators on non-equilibrium hypersonic flows Ankush Bhatia,1 Subrata Roy,1 and Ryan Gosse2 1Applied...a cylindrical body in Mach 17 hypersonic flow is presented. This application focuses on using sinusoidal dielectric barrier discharge plasma actuators

  12. Lévy stable noise-induced transitions: stochastic resonance, resonant activation and dynamic hysteresis

    International Nuclear Information System (INIS)

    Dybiec, Bartłomiej; Gudowska-Nowak, Ewa

    2009-01-01

    A standard approach to analysis of noise-induced effects in stochastic dynamics assumes a Gaussian character of the noise term describing interaction of the analyzed system with its complex surroundings. An additional assumption about the existence of timescale separation between the dynamics of the measured observable and the typical timescale of the noise allows external fluctuations to be modeled as temporally uncorrelated and therefore white. However, in many natural phenomena the assumptions concerning the above mentioned properties of 'Gaussianity' and 'whiteness' of the noise can be violated. In this context, in contrast to the spatiotemporal coupling characterizing general forms of non-Markovian or semi-Markovian Lévy walks, so called Lévy flights correspond to the class of Markov processes which can still be interpreted as white, but distributed according to a more general, infinitely divisible, stable and non-Gaussian law. Lévy noise-driven non-equilibrium systems are known to manifest interesting physical properties and have been addressed in various scenarios of physical transport exhibiting a superdiffusive behavior. Here we present a brief overview of our recent investigations aimed at understanding features of stochastic dynamics under the influence of Lévy white noise perturbations. We find that the archetypal phenomena of noise-induced ordering are robust and can be detected also in systems driven by memoryless, non-Gaussian, heavy-tailed fluctuations with infinite variance

  13. Market Analysis of Soundproof and Noise Reduction Plate

    Directory of Open Access Journals (Sweden)

    Chang Heyu

    2017-01-01

    Full Text Available Since the reform and opening up, China has a booming economy development, transportation industry as an important part of the economic processes has made a considerable progress, and continue to promote the rapid economic development. At the end of 2012, China's highway mileage has reached 4.238 million km and highway mileage ranks first in the world. Transportation in promoting rapid economic development, but also brings the traffic noise which has a tremendous influence on residents’ daily life, and this influence has gradually deepening and widening, in this situation the production of noise reduction panel gradually emerged. In this paper, a noise barriers manufacturer’ business model in Beijing Daxing District and analyze existing data will be analyzed, it will give much guidance and reference for a new noise reduction factory. The study has shown that plant will target all levels of government departments in charge of roads and the property of management department of residence as our customer groups, increasing technological innovation and improving product quality to establish a more extensive business relationships, and gradually formed noise barriers market competitiveness.

  14. Building America Guidance for Identifying and Overcoming Code, Standard, and Rating Method Barriers

    Energy Technology Data Exchange (ETDEWEB)

    Cole, P. C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Halverson, M. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-09-01

    This guidance document was prepared using the input from the meeting summarized in the draft CSI Roadmap to provide Building America research teams and partners with specific information and approaches to identifying and overcoming potential barriers to Building America innovations arising in and/or stemming from codes, standards, and rating methods.

  15. VOLUNTARY NOISE MAPPING FOR SMART CITY

    Directory of Open Access Journals (Sweden)

    V. Poslončec-Petrić

    2016-09-01

    Full Text Available One of the main concept objectives of smart cities is to create a quality living environment that is long-term sustainable and economically justified. In that context, modern cities are aware of the exposure to various forms of physical and non-physical pollution that needs to be remediated, eliminated or reduced. To achieve that it is necessary to quality determine the sources and reasons of each pollution. The most prominent examples of physical pollution that affects the quality of life of citizens in cities are light and noise pollution. Noise pollution or noise, is mostly the consequence of road and rail traffic in cities and it directly affects the health of citizens. Traffic control, reduction of peak congestion, dispersion and traffic redirection or building protective barriers, are ways that cities use to reduce the amount of noise or its effects. To make these measures efficient it is necessary to obtain the information related to the level of noise in certain areas, streets, cities. To achieve this, smart cities use noise mapping. The city of Zagreb since 2012, participates in the i-SCOPE project (interoperable Smart City services trough Open Platform for urban Ecosystems. i-SCOPE delivers an open platform on top of which it develops, three "smart city" services: optimization of energy consumption through a service for accurate assessment of solar energy potential and energy loss at building level, environmental monitoring through a real-time environmental noise mapping service leveraging citizen's involvement will who act as distributed sensors city-wide measuring noise levels through an application on their mobile phones and improved inclusion and personal mobility of aging and diversely able citizens through an accurate personal routing service. The students of Faculty of Geodesy University of Zagreb, who enrolled in the course Thematic Cartography, were actively involved in the voluntary data acquisition in order to monitor the

  16. Voluntary Noise Mapping for Smart City

    Science.gov (United States)

    Poslončec-Petrić, V.; Vuković, V.; Frangeš, S.; Bačić, Ž.

    2016-09-01

    One of the main concept objectives of smart cities is to create a quality living environment that is long-term sustainable and economically justified. In that context, modern cities are aware of the exposure to various forms of physical and non-physical pollution that needs to be remediated, eliminated or reduced. To achieve that it is necessary to quality determine the sources and reasons of each pollution. The most prominent examples of physical pollution that affects the quality of life of citizens in cities are light and noise pollution. Noise pollution or noise, is mostly the consequence of road and rail traffic in cities and it directly affects the health of citizens. Traffic control, reduction of peak congestion, dispersion and traffic redirection or building protective barriers, are ways that cities use to reduce the amount of noise or its effects. To make these measures efficient it is necessary to obtain the information related to the level of noise in certain areas, streets, cities. To achieve this, smart cities use noise mapping. The city of Zagreb since 2012, participates in the i-SCOPE project (interoperable Smart City services trough Open Platform for urban Ecosystems). i-SCOPE delivers an open platform on top of which it develops, three "smart city" services: optimization of energy consumption through a service for accurate assessment of solar energy potential and energy loss at building level, environmental monitoring through a real-time environmental noise mapping service leveraging citizen's involvement will who act as distributed sensors city-wide measuring noise levels through an application on their mobile phones and improved inclusion and personal mobility of aging and diversely able citizens through an accurate personal routing service. The students of Faculty of Geodesy University of Zagreb, who enrolled in the course Thematic Cartography, were actively involved in the voluntary data acquisition in order to monitor the noise in real time

  17. The solar noise barrier project 3. The effects of seasonal spectral variation, cloud cover and heat distribution on the performance of full-scale luminescent solar concentrator panels

    NARCIS (Netherlands)

    Debije, M.G.; Tzikas, C.; de Jong, M.; Kanellis, M.; Slooff, L.H.

    We report on the relative performances of two large-scale luminescent solar concentrator (LSC) noise barriers placed in an outdoor environment monitored for over a year. Comparisons are made for the performances of a number of attached photovoltaic cells with changing spectral illumination, cloud

  18. Acceptable noise level (ANL) with Danish and non-semantic speech materials in adult hearing-aid users

    DEFF Research Database (Denmark)

    Olsen, Steen Østergaard; Lantz, Johannes; Nielsen, Lars Holme

    2012-01-01

    The acceptable noise level (ANL) test is used for quantification of the amount of background noise subjects accept when listening to speech. This study investigates Danish hearing-aid users' ANL performance using Danish and non-semantic speech signals, the repeatability of ANL, and the association...... between ANL and outcome of the international outcome inventory for hearing aids (IOI-HA)....

  19. Barriers to exercise in younger and older non-exercising adult women: a cross sectional study in London, United Kingdom.

    Science.gov (United States)

    El Ansari, Walid; Lovell, Geoff

    2009-04-01

    A survey of 100 women in the south of London, United Kingdom (UK) compared exercise barrier intensities between non-exercising younger (20-27 years) and older (28-35 years) adult women; and examined childcare duties as perceived barriers to exercise. Perceived barriers to exercise were examined using an Exercise Benefits/Barriers Scale (EBBS) comprising four subscales (exercise milieu; time expenditure; physical exertion; family discouragement). Participants' number of children was also noted. Non-exercising older women reported significantly higher total exercise barriers, as well as across three barrier subscales: exercise milieu, time expenditure, and family discouragement. For both age groups, significant correlation existed between number of children and women's total exercise barrier scores. Number of children explained approximately 25% and approximately 30% of the variance of younger and older women's total barrier scores respectively. For both women groups, the strongest correlation between exercise barrier and number of children was for the time expenditure subscale. Broad grouping of 20-35 year old non-exercising women does not reflect a homogenous sample. Age categories employing narrower age brackets are recommended. Issues surrounding family responsibilities e.g. childcare duties may be shared between these groups and require further research and policy attention.

  20. Time Dependence of Entropy Flux and Entropy Production of a Dissipative Dynamical System Driven by Non-Gaussian Noise

    International Nuclear Information System (INIS)

    Guo Yongfeng; Xu Wei; Li Dongxi; Xie Wenxian

    2008-01-01

    A stochastic dissipative dynamical system driven by non-Gaussian noise is investigated. A general approximate Fokker-Planck equation of the system is derived through a path-integral approach. Based on the definition of Shannon's information entropy, the exact time dependence of entropy flux and entropy production of the system is calculated both in the absence and in the presence of non-equilibrium constraint. The present calculation can be used to interpret the interplay of the dissipative constant and non-Gaussian noise on the entropy flux and entropy production

  1. Subcutaneous Tissue Thickness is an Independent Predictor of Image Noise in Cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Staniak, Henrique Lane; Sharovsky, Rodolfo [Hospital Universitário - Universidade de São Paulo, São Paulo, SP (Brazil); Pereira, Alexandre Costa [Hospital das Clínicas - Universidade de São Paulo, São Paulo, SP (Brazil); Castro, Cláudio Campi de; Benseñor, Isabela M.; Lotufo, Paulo A. [Hospital Universitário - Universidade de São Paulo, São Paulo, SP (Brazil); Faculdade de Medicina - Universidade de São Paulo, São Paulo, SP (Brazil); Bittencourt, Márcio Sommer, E-mail: msbittencourt@mail.harvard.edu [Hospital Universitário - Universidade de São Paulo, São Paulo, SP (Brazil)

    2014-01-15

    Few data on the definition of simple robust parameters to predict image noise in cardiac computed tomography (CT) exist. To evaluate the value of a simple measure of subcutaneous tissue as a predictor of image noise in cardiac CT. 86 patients underwent prospective ECG-gated coronary computed tomographic angiography (CTA) and coronary calcium scoring (CAC) with 120 kV and 150 mA. The image quality was objectively measured by the image noise in the aorta in the cardiac CTA, and low noise was defined as noise < 30HU. The chest anteroposterior diameter and lateral width, the image noise in the aorta and the skin-sternum (SS) thickness were measured as predictors of cardiac CTA noise. The association of the predictors and image noise was performed by using Pearson correlation. The mean radiation dose was 3.5 ± 1.5 mSv. The mean image noise in CT was 36.3 ± 8.5 HU, and the mean image noise in non-contrast scan was 17.7 ± 4.4 HU. All predictors were independently associated with cardiac CTA noise. The best predictors were SS thickness, with a correlation of 0.70 (p < 0.001), and noise in the non-contrast images, with a correlation of 0.73 (p < 0.001). When evaluating the ability to predict low image noise, the areas under the ROC curve for the non-contrast noise and for the SS thickness were 0.837 and 0.864, respectively. Both SS thickness and CAC noise are simple accurate predictors of cardiac CTA image noise. Those parameters can be incorporated in standard CT protocols to adequately adjust radiation exposure.

  2. Subcutaneous Tissue Thickness is an Independent Predictor of Image Noise in Cardiac CT

    International Nuclear Information System (INIS)

    Staniak, Henrique Lane; Sharovsky, Rodolfo; Pereira, Alexandre Costa; Castro, Cláudio Campi de; Benseñor, Isabela M.; Lotufo, Paulo A.; Bittencourt, Márcio Sommer

    2014-01-01

    Few data on the definition of simple robust parameters to predict image noise in cardiac computed tomography (CT) exist. To evaluate the value of a simple measure of subcutaneous tissue as a predictor of image noise in cardiac CT. 86 patients underwent prospective ECG-gated coronary computed tomographic angiography (CTA) and coronary calcium scoring (CAC) with 120 kV and 150 mA. The image quality was objectively measured by the image noise in the aorta in the cardiac CTA, and low noise was defined as noise < 30HU. The chest anteroposterior diameter and lateral width, the image noise in the aorta and the skin-sternum (SS) thickness were measured as predictors of cardiac CTA noise. The association of the predictors and image noise was performed by using Pearson correlation. The mean radiation dose was 3.5 ± 1.5 mSv. The mean image noise in CT was 36.3 ± 8.5 HU, and the mean image noise in non-contrast scan was 17.7 ± 4.4 HU. All predictors were independently associated with cardiac CTA noise. The best predictors were SS thickness, with a correlation of 0.70 (p < 0.001), and noise in the non-contrast images, with a correlation of 0.73 (p < 0.001). When evaluating the ability to predict low image noise, the areas under the ROC curve for the non-contrast noise and for the SS thickness were 0.837 and 0.864, respectively. Both SS thickness and CAC noise are simple accurate predictors of cardiac CTA image noise. Those parameters can be incorporated in standard CT protocols to adequately adjust radiation exposure

  3. Investigations of internal noise levels for different target sizes, contrasts, and noise structures

    Science.gov (United States)

    Han, Minah; Choi, Shinkook; Baek, Jongduk

    2014-03-01

    To describe internal noise levels for different target sizes, contrasts, and noise structures, Gaussian targets with four different sizes (i.e., standard deviation of 2,4,6 and 8) and three different noise structures(i.e., white, low-pass, and highpass) were generated. The generated noise images were scaled to have standard deviation of 0.15. For each noise type, target contrasts were adjusted to have the same detectability based on NPW, and the detectability of CHO was calculated accordingly. For human observer study, 3 trained observers performed 2AFC detection tasks, and correction rate, Pc, was calculated for each task. By adding proper internal noise level to numerical observer (i.e., NPW and CHO), detectability of human observer was matched with that of numerical observers. Even though target contrasts were adjusted to have the same detectability of NPW observer, detectability of human observer decreases as the target size increases. The internal noise level varies for different target sizes, contrasts, and noise structures, demonstrating different internal noise levels should be considered in numerical observer to predict the detection performance of human observer.

  4. Non-commutative standard model: model building

    CERN Document Server

    Chaichian, Masud; Presnajder, P

    2003-01-01

    A non-commutative version of the usual electro-weak theory is constructed. We discuss how to overcome the two major problems: (1) although we can have non-commutative U(n) (which we denote by U sub * (n)) gauge theory we cannot have non-commutative SU(n) and (2) the charges in non-commutative QED are quantized to just 0,+-1. We show how the latter problem with charge quantization, as well as with the gauge group, can be resolved by taking the U sub * (3) x U sub * (2) x U sub * (1) gauge group and reducing the extra U(1) factors in an appropriate way. Then we proceed with building the non-commutative version of the standard model by specifying the proper representations for the entire particle content of the theory, the gauge bosons, the fermions and Higgs. We also present the full action for the non-commutative standard model (NCSM). In addition, among several peculiar features of our model, we address the inherentCP violation and new neutrino interactions. (orig.)

  5. Covariance measurement in the presence of non-synchronous trading and market microstructure noise

    NARCIS (Netherlands)

    Griffin, J.E.; Oomen, R.C.A.

    2011-01-01

    This paper studies the problem of covariance estimation when prices are observed non-synchronously and contaminated by i.i.d. microstructure noise. We derive closed form expressions for the bias and variance of three popular covariance estimators, namely realised covariance, realised covariance plus

  6. Random resampling masks: a non-Bayesian one-shot strategy for noise reduction in digital holography.

    Science.gov (United States)

    Bianco, V; Paturzo, M; Memmolo, P; Finizio, A; Ferraro, P; Javidi, B

    2013-03-01

    Holographic imaging may become severely degraded by a mixture of speckle and incoherent additive noise. Bayesian approaches reduce the incoherent noise, but prior information is needed on the noise statistics. With no prior knowledge, one-shot reduction of noise is a highly desirable goal, as the recording process is simplified and made faster. Indeed, neither multiple acquisitions nor a complex setup are needed. So far, this result has been achieved at the cost of a deterministic resolution loss. Here we propose a fast non-Bayesian denoising method that avoids this trade-off by means of a numerical synthesis of a moving diffuser. In this way, only one single hologram is required as multiple uncorrelated reconstructions are provided by random complementary resampling masks. Experiments show a significant incoherent noise reduction, close to the theoretical improvement bound, resulting in image-contrast improvement. At the same time, we preserve the resolution of the unprocessed image.

  7. Enhancement and Noise Statistics Estimation for Non-Stationary Voiced Speech

    DEFF Research Database (Denmark)

    Nørholm, Sidsel Marie; Jensen, Jesper Rindom; Christensen, Mads Græsbøll

    2016-01-01

    In this paper, single channel speech enhancement in the time domain is considered. We address the problem of modelling non-stationary speech by describing the voiced speech parts by a harmonic linear chirp model instead of using the traditional harmonic model. This means that the speech signal...... through simulations on synthetic and speech signals, that the chirp versions of the filters perform better than their harmonic counterparts in terms of output signal-to-noise ratio (SNR) and signal reduction factor. For synthetic signals, the output SNR for the harmonic chirp APES based filter...... is increased 3 dB compared to the harmonic APES based filter at an input SNR of 10 dB, and at the same time the signal reduction factor is decreased. For speech signals, the increase is 1.5 dB along with a decrease in the signal reduction factor of 0.7. As an implicit part of the APES filter, a noise...

  8. Direct estimation and correction of bias from temporally variable non-stationary noise in a channelized Hotelling model observer.

    Science.gov (United States)

    Fetterly, Kenneth A; Favazza, Christopher P

    2016-08-07

    Channelized Hotelling model observer (CHO) methods were developed to assess performance of an x-ray angiography system. The analytical methods included correction for known bias error due to finite sampling. Detectability indices ([Formula: see text]) corresponding to disk-shaped objects with diameters in the range 0.5-4 mm were calculated. Application of the CHO for variable detector target dose (DTD) in the range 6-240 nGy frame(-1) resulted in [Formula: see text] estimates which were as much as 2.9×  greater than expected of a quantum limited system. Over-estimation of [Formula: see text] was presumed to be a result of bias error due to temporally variable non-stationary noise. Statistical theory which allows for independent contributions of 'signal' from a test object (o) and temporally variable non-stationary noise (ns) was developed. The theory demonstrates that the biased [Formula: see text] is the sum of the detectability indices associated with the test object [Formula: see text] and non-stationary noise ([Formula: see text]). Given the nature of the imaging system and the experimental methods, [Formula: see text] cannot be directly determined independent of [Formula: see text]. However, methods to estimate [Formula: see text] independent of [Formula: see text] were developed. In accordance with the theory, [Formula: see text] was subtracted from experimental estimates of [Formula: see text], providing an unbiased estimate of [Formula: see text]. Estimates of [Formula: see text] exhibited trends consistent with expectations of an angiography system that is quantum limited for high DTD and compromised by detector electronic readout noise for low DTD conditions. Results suggest that these methods provide [Formula: see text] estimates which are accurate and precise for [Formula: see text]. Further, results demonstrated that the source of bias was detector electronic readout noise. In summary, this work presents theory and methods to test for the

  9. The non-English major lecturers speak English: The barriers encountered by adult learners

    Directory of Open Access Journals (Sweden)

    Ahmad Madkur

    2018-03-01

    Full Text Available This study was aimed at investigating the difficulties and problems faced by non-English major lecturers when they were taking a part in English discussion. This study was a qualitative descriptive research involving 10 non-English major lecturers who took a part in a twice-a-week discussion so-called English Corner. To collect the data, in-depth interview and observation were used. The collected data were analyzed by using Miles and Huberman’s interactive data analysis data model consisting of data reduction, data display and data verifying. The result of the study showed that those barriers could be classified into three problems namely socio-cultural, linguistic and interpersonal problems. The found barriers were expected to be a consideration to find out the solution to make the betterment of English learning among lecturers with the non-English background of study.

  10. CP Studies and Non-Standard Higgs Physics

    DEFF Research Database (Denmark)

    Kraml, S.; Accomando, E.; G. Akeroyd, A.

    2006-01-01

    There are many possibilities for new physics beyond the Standard Model that feature non-standard Higgs sectors. These may introduce new sources of CP violation, and there may be mixing between multiple Higgs bosons or other new scalar bosons. Alternatively, the Higgs may be a composite state......, or there may even be no Higgs at all. These non-standard Higgs scenarios have important implications for collider physics as well as for cosmology, and understanding their phenomenology is essential for a full comprehension of electroweak symmetry breaking. This report discusses the most relevant theories...

  11. Use of co-combustion bottom ash to design an acoustic absorbing material for highway noise barriers.

    Science.gov (United States)

    Arenas, Celia; Leiva, Carlos; Vilches, Luis F; Cifuentes, Héctor

    2013-11-01

    The present study aims to determine and evaluate the applicability of a new product consisting of coal bottom ash mixed with Portland cement in the application of highway noise barriers. In order to effectively recycle the bottom ash, the influence of the grain particle size of bottom ash, the thickness of the panel and the combination of different layers with various particle sizes have been studied, as well as some environmental properties including leachability (EN-12457-4, NEN-7345) and radioactivity tests. Based on the obtained results, the acoustic properties of the final composite material were similar or even better than those found in porous concrete used for the same application. According to this study, the material produced presented no environmental risk. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. SELECTED PROBLEMS OF PROTECTION AGAINST ROAD TRAFFIC NOISE

    Directory of Open Access Journals (Sweden)

    Władysław Gardziejczyk

    2015-11-01

    Full Text Available The paper presents factors for assessment of road traffic noise level and possible actions towards the minimization of excessive noise in the roadway neighborhood. Changes of equivalent sound level values were analyzed in relation to traffic intensity, categorization and vehicles speed. In relation to measures reducing noise level in roadway’s surroundings particular attention was given to anti-noise protections and tyre/noise reduction. Acoustic effectiveness of specific solutions was showed based on chosen examples. It was proved that when admissible noise level is slightly exceeded the need for noise barrier use may be replaced by a proper design and maintenance of road pavement or by enforcement of speed limit.

  13. A tunable acoustic barrier based on periodic arrays of subwavelength slits

    Directory of Open Access Journals (Sweden)

    Constanza Rubio

    2015-05-01

    Full Text Available The most usual method to reduce undesirable enviromental noise levels during its transmission is the use of acoustic barriers. A novel type of acoustic barrier based on sound transmission through subwavelength slits is presented. This system consists of two rows of periodic repetition of vertical rigid pickets separated by a slit of subwavelength width and with a misalignment between them. Here, both the experimental and the numerical analyses are presented. The acoustic barrier proposed can be easily built and is frequency tunable. The results demonstrated that the proposed barrier can be tuned to mitigate a band noise without excesive barrier thickness. The use of this system as an environmental acoustic barrier has certain advantages with regard to the ones currently used both from the constructive and the acoustical point of view.

  14. A tunable acoustic barrier based on periodic arrays of subwavelength slits

    Science.gov (United States)

    Rubio, Constanza; Uris, Antonio; Candelas, Pilar; Belmar, Francisco; Gomez-Lozano, Vicente

    2015-05-01

    The most usual method to reduce undesirable enviromental noise levels during its transmission is the use of acoustic barriers. A novel type of acoustic barrier based on sound transmission through subwavelength slits is presented. This system consists of two rows of periodic repetition of vertical rigid pickets separated by a slit of subwavelength width and with a misalignment between them. Here, both the experimental and the numerical analyses are presented. The acoustic barrier proposed can be easily built and is frequency tunable. The results demonstrated that the proposed barrier can be tuned to mitigate a band noise without excesive barrier thickness. The use of this system as an environmental acoustic barrier has certain advantages with regard to the ones currently used both from the constructive and the acoustical point of view.

  15. Comparison of Auditory Brainstem Response in Noise Induced Tinnitus and Non-Tinnitus Control Subjects

    Directory of Open Access Journals (Sweden)

    Ghassem Mohammadkhani

    2009-12-01

    Full Text Available Background and Aim: Tinnitus is an unpleasant sound which can cause some behavioral disorders. According to evidence the origin of tinnitus is not only in peripheral but also in central auditory system. So evaluation of central auditory system function is necessary. In this study Auditory brainstem responses (ABR were compared in noise induced tinnitus and non-tinnitus control subjects.Materials and Methods: This cross-sectional, descriptive and analytic study is conducted in 60 cases in two groups including of 30 noise induced tinnitus and 30 non-tinnitus control subjects. ABRs were recorded ipsilateraly and contralateraly and their latencies and amplitudes were analyzed.Results: Mean interpeak latencies of III-V (p= 0.022, I-V (p=0.033 in ipsilatral electrode array and mean absolute latencies of IV (p=0.015 and V (p=0.048 in contralatral electrode array were significantly increased in noise induced tinnitus group relative to control group. Conclusion: It can be concluded from that there are some decrease in neural transmission time in brainstem and there are some sign of involvement of medial nuclei in olivery complex in addition to lateral lemniscus.

  16. A robust and coherent network statistic for detecting gravitational waves from inspiralling compact binaries in non-Gaussian noise

    CERN Document Server

    Bose, S

    2002-01-01

    The robust statistic proposed by Creighton (Creighton J D E 1999 Phys. Rev. D 60 021101) and Allen et al (Allen et al 2001 Preprint gr-gc/010500) for the detection of stationary non-Gaussian noise is briefly reviewed. We compute the robust statistic for generic weak gravitational-wave signals in the mixture-Gaussian noise model to an accuracy higher than in those analyses, and reinterpret its role. Specifically, we obtain the coherent statistic for detecting gravitational-wave signals from inspiralling compact binaries with an arbitrary network of earth-based interferometers. Finally, we show that excess computational costs incurred owing to non-Gaussianity is negligible compared to the cost of detection in Gaussian noise.

  17. Barriers to Exercise in Younger and Older Non-Exercising Adult Women: A Cross Sectional Study in London, United Kingdom

    Science.gov (United States)

    Ansari, Walid El; Lovell, Geoff

    2009-01-01

    A survey of 100 women in the south of London, United Kingdom (UK) compared exercise barrier intensities between non-exercising younger (20–27 years) and older (28–35 years) adult women; and examined childcare duties as perceived barriers to exercise. Perceived barriers to exercise were examined using an Exercise Benefits/Barriers Scale (EBBS) comprising four subscales (exercise milieu; time expenditure; physical exertion; family discouragement). Participants’ number of children was also noted. Non-exercising older women reported significantly higher total exercise barriers, as well as across three barrier subscales: exercise milieu, time expenditure, and family discouragement. For both age groups, significant correlation existed between number of children and women’s total exercise barrier scores. Number of children explained ≈25% and ≈30% of the variance of younger and older women’s total barrier scores respectively. For both women groups, the strongest correlation between exercise barrier and number of children was for the time expenditure subscale. Broad grouping of 20–35 year old non-exercising women does not reflect a homogenous sample. Age categories employing narrower age brackets are recommended. Issues surrounding family responsibilities e.g. childcare duties may be shared between these groups and require further research and policy attention. PMID:19440527

  18. Barriers to Exercise in Younger and Older Non-Exercising Adult Women: A Cross Sectional Study in London, United Kingdom

    Directory of Open Access Journals (Sweden)

    Geoff Lovell

    2009-04-01

    Full Text Available A survey of 100 women in the south of London, United Kingdom (UK compared exercise barrier intensities between non-exercising younger (20-27 years and older (28-35 years adult women; and examined childcare duties as perceived barriers to exercise. Perceived barriers to exercise were examined using an Exercise Benefits/Barriers Scale (EBBS comprising four subscales (exercise milieu; time expenditure; physical exertion; family discouragement. Participants’ number of children was also noted. Non-exercising older women reported significantly higher total exercise barriers, as well as across three barrier subscales: exercise milieu, time expenditure, and family discouragement. For both age groups, significant correlation existed between number of children and women’s total exercise barrier scores. Number of children explained »25% and »30% of the variance of younger and older women’s total barrier scores respectively. For both women groups, the strongest correlation between exercise barrier and number of children was for the time expenditure subscale. Broad grouping of 20-35 year old non-exercising women does not reflect a homogenous sample. Age categories employing narrower age brackets are recommended. Issues surrounding family responsibilities e.g. childcare duties may be shared between these groups and require further research and policy attention.

  19. Quantum 1/f noise in non-degerate semiconductors and emission statistics of alpha particles

    International Nuclear Information System (INIS)

    Kousik, G.S.

    1985-01-01

    Charged particle scattering is accompanied by the emission of soft photons. Handel's theory of 1/f noise, based on the infrared divergent coupling of the system to the electromagnetic field or other elementary excitations, states that the current associated with a beam of scattered particles will exhibit 1/f noise. The fraction of the particles scattered with an energy loss epsilon to soft photon emission is proportional to 1/epsilon and herein lies the origin of the quantum theory of 1/f noise. The 1/f noise caused by mobility fluctuations in semiconductors is related to the scattering cross section fluctuation given by Handel's theory, through the relaxation time. Chapters Two through Five of this dissertation presents the results of the detailed calculation of mobility fluctuation 1/f noise and Hooge parameter in nondegenerate semiconductors. Numerical results are given for silicon and gallium arsenide. Data obtained from extensive measurements on counting techniques for alpha-particles radioactive decay from a source containing 94 Pu 239 , 95 Am 241 and 96 Cm 244 are presented in Chapters Six and Seven of this dissertation. These data show that the statistics are non-Poissonian for large counting times (of the order of 1000 minutes) contrary to the popular belief that alpha-decay is an example of Poissonian statistics. Measurements of the Allan variance indicated the presence of a slow Lorentzian flicker noise and 1/f noise and the magnitude of the noise for large counting times is considerably larger than that predicted by Poissonian statistics

  20. Non-standard antennas

    CERN Document Server

    Le Chevalier, Francois; Staraj, Robert

    2013-01-01

    This book aims at describing the wide variety of new technologies and concepts of non-standard antenna systems - reconfigurable, integrated, terahertz, deformable, ultra-wideband, using metamaterials, or MEMS,  etc, and how they open the way to a wide range of applications, from personal security and communications to multifunction radars and towed sonars, or satellite navigation systems, with space-time diversity on transmit and receive. A reference book for designers  in this lively scientific community linking antenna experts and signal processing engineers.

  1. A Non-standard Empirical Likelihood for Time Series

    DEFF Research Database (Denmark)

    Nordman, Daniel J.; Bunzel, Helle; Lahiri, Soumendra N.

    Standard blockwise empirical likelihood (BEL) for stationary, weakly dependent time series requires specifying a fixed block length as a tuning parameter for setting confidence regions. This aspect can be difficult and impacts coverage accuracy. As an alternative, this paper proposes a new version...... of BEL based on a simple, though non-standard, data-blocking rule which uses a data block of every possible length. Consequently, the method involves no block selection and is also anticipated to exhibit better coverage performance. Its non-standard blocking scheme, however, induces non......-standard asymptotics and requires a significantly different development compared to standard BEL. We establish the large-sample distribution of log-ratio statistics from the new BEL method for calibrating confidence regions for mean or smooth function parameters of time series. This limit law is not the usual chi...

  2. Does the Finite Size of Electrons Affect Quantum Noise in Electronic Devices?

    International Nuclear Information System (INIS)

    Colomés, E; Marian, D; Oriols, X

    2015-01-01

    Quantum transport is commonly studied with the use of quasi-particle infinite- extended states. This leads to a powerful formalism, the scattering-states theory, able to capture in compact formulas quantities of interest, such as average current, noise, etc.. However, when investigating the spatial size-dependence of quasi-particle wave packets in quantum noise with exchange and tunneling, unexpected new terms appear in the quantum noise expression. For this purpose, the two particle transmission and reflection probabilities for two initial one-particle wave packets (with opposite central momentums) spatially localized at each side of a potential barrier are studied. After the interaction, each wave packet splits into a transmitted and a reflected component. It can be shown that the probability of detecting two (identically injected) electrons at the same side of the barrier is different from zero in very common (single or double barrier) scenarios. This originates an increase of quantum noise which cannot be obtained through the scattering states formalism. (paper)

  3. Visuo-manual tracking: does intermittent control with aperiodic sampling explain linear power and non-linear remnant without sensorimotor noise?

    Science.gov (United States)

    Gollee, Henrik; Gawthrop, Peter J; Lakie, Martin; Loram, Ian D

    2017-11-01

    A human controlling an external system is described most easily and conventionally as linearly and continuously translating sensory input to motor output, with the inevitable output remnant, non-linearly related to the input, attributed to sensorimotor noise. Recent experiments show sustained manual tracking involves repeated refractoriness (insensitivity to sensory information for a certain duration), with the temporary 200-500 ms periods of irresponsiveness to sensory input making the control process intrinsically non-linear. This evidence calls for re-examination of the extent to which random sensorimotor noise is required to explain the non-linear remnant. This investigation of manual tracking shows how the full motor output (linear component and remnant) can be explained mechanistically by aperiodic sampling triggered by prediction error thresholds. Whereas broadband physiological noise is general to all processes, aperiodic sampling is associated with sensorimotor decision making within specific frontal, striatal and parietal networks; we conclude that manual tracking utilises such slow serial decision making pathways up to several times per second. The human operator is described adequately by linear translation of sensory input to motor output. Motor output also always includes a non-linear remnant resulting from random sensorimotor noise from multiple sources, and non-linear input transformations, for example thresholds or refractory periods. Recent evidence showed that manual tracking incurs substantial, serial, refractoriness (insensitivity to sensory information of 350 and 550 ms for 1st and 2nd order systems respectively). Our two questions are: (i) What are the comparative merits of explaining the non-linear remnant using noise or non-linear transformations? (ii) Can non-linear transformations represent serial motor decision making within the sensorimotor feedback loop intrinsic to tracking? Twelve participants (instructed to act in three prescribed

  4. Non-standard Employment in the Nordics – towards precarious work?

    DEFF Research Database (Denmark)

    Rasmussen, Stine; Nätti, Jouko; Larsen, Trine Pernille

    2018-01-01

    This article examines non-standard employment and precariousness in four Nordic countries (Denmark, Sweden, Finland and Norway). Drawing on data from the Labour Force Survey from 1995-2015, the article investigates and compares recent developments of non-standard employment in the countries and w...... to be largely integrated in the Nordic labour markets, it still entails precarious elements in certain countries. Norway and Denmark stand out as less insecure labour markets, while Finland and Sweden have more precariousness associated with non-standard employment.......This article examines non-standard employment and precariousness in four Nordic countries (Denmark, Sweden, Finland and Norway). Drawing on data from the Labour Force Survey from 1995-2015, the article investigates and compares recent developments of non-standard employment in the countries...... and whether fixed-term contracts, temporary agency work, marginal part-time work and solo self-employment have precarious elements (income or job insecurity). We conclude that non-standard employment has remained rather stable in all four countries over time. However, although non-standard employment seems...

  5. Perceived exercise benefits and barriers of non-exercising female university students in the United Kingdom.

    Science.gov (United States)

    Lovell, Geoff P; El Ansari, Walid; Parker, John K

    2010-03-01

    Many individuals do not engage in sufficient physical activity due to low perceived benefits and high perceived barriers to exercise. Given the increasing incidence of obesity and obesity related health disorders, this topic requires further exploration. We used the Exercise Benefits/Barriers Scale to assess perceived benefit and barrier intensities to exercise in 200 non-exercising female university students (mean age 19.3 years, SD = 1.06) in the UK. Although our participants were selected because they self reported themselves to be non-exercising, however they reported significantly higher perceived benefits from exercise than perceived barriers to exercise [t(199) = 6.18, p exercise was physical performance followed by the benefits of psychological outlook, preventive health, life enhancement, and then social interaction. Physical performance was rated significantly higher than all other benefits. Psychological outlook and preventive health were not rated significantly different, although both were significantly higher than life enhancement and social interaction. Life enhancement was also rated significantly higher than social interaction. The greatest perceived barrier to exercise was physical exertion, which was rated significantly higher than time expenditure, exercise milieu, and family discouragement barriers. Implications from this investigation for the design of physical activity programmes include the importance, for females, of a perception of high benefit/barrier ratio that could be conducive to participation in exercise. Applied interventions need to assist female students to 'disengage' from or overcome any perceived 'unpleasantness' of physical exertion during physical activity (decrease their perceived barriers), and to further highlight the multiple health and other benefits of regular exercising (increase their perceived benefits).

  6. Non-unitarity, sterile neutrinos, and non-standard neutrino interactions

    Energy Technology Data Exchange (ETDEWEB)

    Blennow, Mattias [Department of Theoretical Physics, School of Engineering Sciences, KTH Royal Institute of Technology, Albanova University Center, 106 91 Stockholm (Sweden); Coloma, Pilar [Theoretical Physics Department, Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States); Fernandez-Martinez, Enrique; Hernandez-Garcia, Josu [Departamento de Física Teórica, Universidad Autónoma de Madrid, Cantoblanco E-28049 Madrid (Spain); Instituto de Física Teórica UAM/CSIC, Calle Nicolás Cabrera 13-15, Cantoblanco E-28049 Madrid (Spain); Lopez-Pavon, Jacobo [INFN, Sezione di Genova, via Dodecaneso 33, 16146 Genova (Italy); CERN, Theoretical Physics Department, Geneva (Switzerland)

    2017-04-27

    The simplest Standard Model extension to explain neutrino masses involves the addition of right-handed neutrinos. At some level, this extension will impact neutrino oscillation searches. In this work we explore the differences and similarities between the case in which these neutrinos are kinematically accessible (sterile neutrinos) or not (mixing matrix non-unitarity). We clarify apparent inconsistencies in the present literature when using different parametrizations to describe these effects and recast both limits in the popular neutrino non-standard interaction (NSI) formalism. We find that, in the limit in which sterile oscillations are averaged out at the near detector, their effects at the far detector coincide with non-unitarity at leading order, even in presence of a matter potential. We also summarize the present bounds existing in both limits and compare them with the expected sensitivities of near-future facilities taking the DUNE proposal as a benchmark. We conclude that non-unitarity effects are too constrained to impact present or near future neutrino oscillation facilities but that sterile neutrinos can play an important role at long baseline experiments. The role of the near detector is also discussed in detail.

  7. Development of a coincidence system for radio-nuclide standardization using surface barrier detectors

    International Nuclear Information System (INIS)

    Koskinas, M.F.

    1988-01-01

    A system for the standardization of alpha-gamma or electron-X radionuclide emitters has been developed in the present work. The system consists of one or two surface barrier detectors for alpha or electron detection which are coupled to thin-window NaI (T1) crystals suitable for low energy X or gamma ray detection. The performance of the system has been verified by means of the standardization of 241 Am, 137 Cs and 109 Cd solutions. The activity has been obtained using the extrapolation method applied to the 4Πα-γ and 2Πe c -X coincidence technique. The surface barrier detection efficiency was varied by placing absorbers over the radioactive sources or by changing the source to detector distance. The results were compared to those obtained using conventional absolute systems based on gas-flow and pressurized 4Π proportional counters, or using radioactive solutions standardized in international comparisons spondored by the Bureau International des Poids et Mesures. The expect and measured activities agree within the experimental uncertainties which were: 0.2 % for 241 Am, 0.7% for 137 Cs and 0.6% for 109 Cd. The ratio between the probabilities of (electron capture + internal conversion) and internal conversion for the K-shell of 109 Cd has been determined. The result is: 2.8883 ± 0.016. (author) [pt

  8. Reversible, non-barrier male contraception: status and prospects.

    Science.gov (United States)

    Hoesl, C E; Saad, F; Pöppel, M; Altwein, J E

    2005-11-01

    Male, non-barrier, contraceptive options are limited to vasectomy and inadequate methods such as withdrawal and periodic abstinence. Herein we give an overview of current research on male contraception by pharmacological means. Literature search of PubMed documented publications and abstracts from meetings. Cross-cultural surveys show men's willingness to carry contraceptive responsibility. Clinical trials substantiate that hormonal contraception involving suppression of gonadotropins holds the best promise to provide a male pharmacological contraceptive. Androgens have been demonstrated to induce reversible infertility particularly in combination with certain progestins and GnRH antagonists. Advances in non-endocrine contraception include intervention with triptolide derivatives, alkylated imino sugars, and immunization by eppin. The prospect of a pharmacological, male contraceptive has been considerably advanced in recent years. Long-term studies involving a greater number of subjects may result in a safe, reversible and effective means. Asia is likely to be the first market for male, hormonal contraceptive methods. The clinical evaluation of non-endocrine approaches may ultimately lead to an alternative to hormone-based male contraception.

  9. New Insight in Loss of Gut Barrier during Major Non-Abdominal Surgery.

    Directory of Open Access Journals (Sweden)

    Joep P M Derikx

    Full Text Available Gut barrier loss has been implicated as a critical event in the occurrence of postoperative complications. We aimed to study the development of gut barrier loss in patients undergoing major non-abdominal surgery.Twenty consecutive children undergoing spinal fusion surgery were included. This kind of surgery is characterized by long operation time, significant blood loss, prolonged systemic hypotension, without directly leading to compromise of the intestines by intestinal manipulation or use of extracorporeal circulation. Blood was collected preoperatively, every two hours during surgery and 2, 4, 15 and 24 hours postoperatively. Gut mucosal barrier was assessed by plasma markers for enterocyte damage (I-FABP, I-BABP and urinary presence of tight junction protein claudin-3. Intestinal mucosal perfusion was measured by gastric tonometry (P(rCO2, P(r-aCO2-gap. Plasma concentration of I-FABP, I-BABP and urinary expression of claudin-3 increased rapidly and significantly after the onset of surgery in most children. Postoperatively, all markers decreased promptly towards baseline values together with normalisation of MAP. Plasma levels of I-FABP, I-BABP were significantly negatively correlated with MAP at (1/2 hour before blood sampling (-0.726 (p<0.001, -0.483 (P<0.001, respectively. Furthermore, circulating I-FABP correlated with gastric mucosal P(rCO2, P(r-aCO2-gap measured at the same time points (0.553 (p = 0.040, 0.585 (p = 0.028, respectively.This study shows the development of gut barrier loss in children undergoing major non-abdominal surgery, which is related to preceding hypotension and mesenterial hypoperfusion. These data shed new light on the potential role of peroperative circulatory perturbation and intestinal barrier loss.

  10. New Insight in Loss of Gut Barrier during Major Non-Abdominal Surgery

    Science.gov (United States)

    Derikx, Joep P. M.; van Waardenburg, Dick A.; Thuijls, Geertje; Willigers, Henriëtte M.; Koenraads, Marianne; van Bijnen, Annemarie A.; Heineman, Erik; Poeze, Martijn; Ambergen, Ton; van Ooij, André; van Rhijn, Lodewijk W.; Buurman, Wim A.

    2008-01-01

    Background Gut barrier loss has been implicated as a critical event in the occurrence of postoperative complications. We aimed to study the development of gut barrier loss in patients undergoing major non-abdominal surgery. Methodology/Principal Findings Twenty consecutive children undergoing spinal fusion surgery were included. This kind of surgery is characterized by long operation time, significant blood loss, prolonged systemic hypotension, without directly leading to compromise of the intestines by intestinal manipulation or use of extracorporeal circulation. Blood was collected preoperatively, every two hours during surgery and 2, 4, 15 and 24 hours postoperatively. Gut mucosal barrier was assessed by plasma markers for enterocyte damage (I-FABP, I-BABP) and urinary presence of tight junction protein claudin-3. Intestinal mucosal perfusion was measured by gastric tonometry (PrCO2, Pr-aCO2-gap). Plasma concentration of I-FABP, I-BABP and urinary expression of claudin-3 increased rapidly and significantly after the onset of surgery in most children. Postoperatively, all markers decreased promptly towards baseline values together with normalisation of MAP. Plasma levels of I-FABP, I-BABP were significantly negatively correlated with MAP at ½ hour before blood sampling (−0.726 (p<0.001), −0.483 (P<0.001), respectively). Furthermore, circulating I-FABP correlated with gastric mucosal PrCO2, Pr-aCO2-gap measured at the same time points (0.553 (p = 0.040), 0.585 (p = 0.028), respectively). Conclusions/Significance This study shows the development of gut barrier loss in children undergoing major non-abdominal surgery, which is related to preceding hypotension and mesenterial hypoperfusion. These data shed new light on the potential role of peroperative circulatory perturbation and intestinal barrier loss. PMID:19088854

  11. Assessment of non-cost barriers to renewable energy growth in EU Member States - AEON

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    The accelerated deployment of renewable energy technologies has become a major priority for public policy makers across the globe. In the last two decades, most of the debate concerning the promotion of renewables was focused on the financial support schemes and on improving grid access conditions for renewable electricity. Of course, these are crucial issues which will continue to deserve serious attention in the future. However, during the last few years, the importance of tackling non-financial and non-technical barriers to renewable electricity, heat and transport has gained the attention of many policy analysts. In June 2009, Directive 2009/28/EC on the promotion of the use of energy from renewable sources, entered into force. The articles 13, 14 and 16 of the Directive contain a number of requirements for Member States to address or remove non-cost barriers to the increased deployment of renewable energy sources. This study presents among others an overview of these barriers in all EU Member States; their history, their impact on renewable energy deployment and suggestions for policy solutions, where feasible. Separate studies were carried out for 27 EU-countries and made available in a zip-file.

  12. Noise barriers and the harmonoise sound propagation model

    NARCIS (Netherlands)

    Salomons, E.M.; Maercke, D. van; Randrianoelina, A.

    2009-01-01

    The Harmonoise sound propagation model ('the Harmonoise engineering model') was developed in the European project Harmonoise (2001-2004) for road and rail traffic noise. In 2008, CSTB Grenoble and TNO Delft have prepared a detailed description of the various steps involved in a calculation with the

  13. GIS-Based Noise Simulation Open Source Software: N-GNOIS

    Science.gov (United States)

    Vijay, Ritesh; Sharma, A.; Kumar, M.; Shende, V.; Chakrabarti, T.; Gupta, Rajesh

    2015-12-01

    Geographical information system (GIS)-based noise simulation software (N-GNOIS) has been developed to simulate the noise scenario due to point and mobile sources considering the impact of geographical features and meteorological parameters. These have been addressed in the software through attenuation modules of atmosphere, vegetation and barrier. N-GNOIS is a user friendly, platform-independent and open geospatial consortia (OGC) compliant software. It has been developed using open source technology (QGIS) and open source language (Python). N-GNOIS has unique features like cumulative impact of point and mobile sources, building structure and honking due to traffic. Honking is the most common phenomenon in developing countries and is frequently observed on any type of roads. N-GNOIS also helps in designing physical barrier and vegetation cover to check the propagation of noise and acts as a decision making tool for planning and management of noise component in environmental impact assessment (EIA) studies.

  14. NON-STANDARD FORMS OF EMPLOYMENT IN BUSINESS ORGANIZATIONS

    Directory of Open Access Journals (Sweden)

    A. E. Chekanov

    2013-01-01

    Full Text Available The article discusses the emergence and development of non-standard forms of employment and flexible working. The causes of their use reflects the results of research conducted in the workplace. Non-standard forms of employment and attractive today as they allow to expand the circle of the workforce.

  15. Noise alters guinea pig's blood-labyrinth barrier ultrastructure and permeability along with a decrease of cochlear Claudin-5 and Occludin.

    Science.gov (United States)

    Wu, Yong-Xiang; Zhu, Guo-Xia; Liu, Xin-Qin; Sun, Fei; Zhou, Ke; Wang, Shuang; Wang, Chun-Mei; Jia, Jin-Wen; Song, Jian-Tao; Lu, Lian-Jun

    2014-12-24

    Noise exposure (NE) is a severe modern health hazard that induces hearing impairment. However, the noise-induced ultrastructural changes of blood-labyrinth barrier (BLB) and the potential involvements of tight junction proteins (TJP) remain inconclusive. We investigated the effects of NE on not only the ultrastructure of cochlea and permeability of BLB but also the expression of TJP within the guinea pig cochlea. Male albino guinea pigs were exposed to white noise for 4 h or 2 consecutive days (115 dB sound pressure level, 6 hours per day) and the hearing impairments and light microscopic change of BLB were evaluated with auditory brainstem responses (ABR) and the cochlear sensory epithelia surface preparation, respectively. The cochlear ultrastructure and BLB permeability after NE 2d were revealed with transmission electron microscope (TEM) and lanthanum nitrate-tracing techniques, respectively. The potential alterations of TJPs Claudin-5 and Occludin were quantified with immunohistochemistry and western blot. NE induced significant hearing impairment and NE 2d contributed to significant outer hair cell (OHC) loss that is most severe in the first row of outer hair cells. Furthermore, the loosen TJ and an obvious leakage of lanthanum nitrate particles beneath the basal lamina were revealed with TEM. Moreover, a dose-dependent decrease of Claudin-5 and Occludin was observed in the cochlea after NE. All these findings suggest that both decrease of Claudin-5 and Occludin and increased BLB permeability are involved in the pathologic process of noise-induced hearing impairment; however, the causal relationship and underlying mechanisms should be further investigated.

  16. SU-F-I-80: Correction for Bias in a Channelized Hotelling Model Observer Caused by Temporally Variable Non-Stationary Noise

    International Nuclear Information System (INIS)

    Favazza, C; Fetterly, K

    2016-01-01

    Purpose: Application of a channelized Hotelling model observer (CHO) over a wide range of x-ray angiography detector target dose (DTD) levels demonstrated substantial bias for conditions yielding low detectability indices (d’), including low DTD and small test objects. The purpose of this work was to develop theory and methods to correct this bias. Methods: A hypothesis was developed wherein the measured detectability index (d’b) for a known test object is positively biased by temporally variable non-stationary noise in the images. Hotelling’s T2 test statistic provided the foundation for a mathematical theory which accounts for independent contributions to the measured d’b value from both the test object (d’o) and non-stationary noise (d’ns). Experimental methods were developed to directly estimate d’o by determining d’ns and subtracting it from d’b, in accordance with the theory. Specifically, d’ns was determined from two sets of images from which the traditional test object was withheld. This method was applied to angiography images with DTD levels in the range 0 to 240 nGy and for disk-shaped iodine-based contrast targets with diameters 0.5 to 4.0 mm. Results: Bias in d’ was evidenced by d’b values which exceeded values expected from a quantum limited imaging system and decreasing object size and DTD. d’ns increased with decreasing DTD, reaching a maximum of 2.6 for DTD = 0. Bias-corrected d’o estimates demonstrated sub-quantum limited performance of the x-ray angiography for low DTD. Findings demonstrated that the source of non-stationary noise was detector electronic readout noise. Conclusion: Theory and methods to estimate and correct bias in CHO measurements from temporally variable non-stationary noise were presented. The temporal non-stationary noise was shown to be due to electronic readout noise. This method facilitates accurate estimates of d’ values over a large range of object size and detector target dose.

  17. SU-F-I-80: Correction for Bias in a Channelized Hotelling Model Observer Caused by Temporally Variable Non-Stationary Noise

    Energy Technology Data Exchange (ETDEWEB)

    Favazza, C; Fetterly, K [Mayo Clinic, Rochester, MN (United States)

    2016-06-15

    Purpose: Application of a channelized Hotelling model observer (CHO) over a wide range of x-ray angiography detector target dose (DTD) levels demonstrated substantial bias for conditions yielding low detectability indices (d’), including low DTD and small test objects. The purpose of this work was to develop theory and methods to correct this bias. Methods: A hypothesis was developed wherein the measured detectability index (d’b) for a known test object is positively biased by temporally variable non-stationary noise in the images. Hotelling’s T2 test statistic provided the foundation for a mathematical theory which accounts for independent contributions to the measured d’b value from both the test object (d’o) and non-stationary noise (d’ns). Experimental methods were developed to directly estimate d’o by determining d’ns and subtracting it from d’b, in accordance with the theory. Specifically, d’ns was determined from two sets of images from which the traditional test object was withheld. This method was applied to angiography images with DTD levels in the range 0 to 240 nGy and for disk-shaped iodine-based contrast targets with diameters 0.5 to 4.0 mm. Results: Bias in d’ was evidenced by d’b values which exceeded values expected from a quantum limited imaging system and decreasing object size and DTD. d’ns increased with decreasing DTD, reaching a maximum of 2.6 for DTD = 0. Bias-corrected d’o estimates demonstrated sub-quantum limited performance of the x-ray angiography for low DTD. Findings demonstrated that the source of non-stationary noise was detector electronic readout noise. Conclusion: Theory and methods to estimate and correct bias in CHO measurements from temporally variable non-stationary noise were presented. The temporal non-stationary noise was shown to be due to electronic readout noise. This method facilitates accurate estimates of d’ values over a large range of object size and detector target dose.

  18. Building America Guidance for Identifying and Overcoming Code, Standard, and Rating Method Barriers

    Energy Technology Data Exchange (ETDEWEB)

    Cole, Pamala C.; Halverson, Mark A.

    2013-09-01

    The U.S. Department of Energy’s (DOE) Building America program implemented a new Codes and Standards Innovation (CSI) Team in 2013. The Team’s mission is to assist Building America (BA) research teams and partners in identifying and resolving conflicts between Building America innovations and the various codes and standards that govern the construction of residences. A CSI Roadmap was completed in September, 2013. This guidance document was prepared using the information in the CSI Roadmap to provide BA research teams and partners with specific information and approaches to identifying and overcoming potential barriers to Building America (BA) innovations arising in and/or stemming from codes, standards, and rating methods. For more information on the BA CSI team, please email: CSITeam@pnnl.gov

  19. Perceived Exercise Benefits and Barriers of Non-Exercising Female University Students in the United Kingdom

    Directory of Open Access Journals (Sweden)

    John K. Parker

    2010-03-01

    Full Text Available Many individuals do not engage in sufficient physical activity due to low perceived benefits and high perceived barriers to exercise. Given the increasing incidence of obesity and obesity related health disorders, this topic requires further exploration. We used the Exercise Benefits/Barriers Scale to assess perceived benefit and barrier intensities to exercise in 200 non-exercising female university students (mean age 19.3 years, SD = 1.06 in the UK. Although our participants were selected because they self reported themselves to be non-exercising, however they reported significantly higher perceived benefits from exercise than perceived barriers to exercise [t(199 = 6.18, p < 0.001], and their perceived benefit/barrier ratio was 1.33. The greatest perceived benefit from exercise was physical performance followed by the benefits of psychological outlook, preventive health, life enhancement, and then social interaction. Physical performance was rated significantly higher than all other benefits. Psychological outlook and preventive health were not rated significantly different, although both were significantly higher than life enhancement and social interaction. Life enhancement was also rated significantly higher than social interaction. The greatest perceived barrier to exercise was physical exertion, which was rated significantly higher than time expenditure, exercise milieu, and family discouragement barriers. Implications from this investigation for the design of physical activity programmes include the importance, for females, of a perception of high benefit/barrier ratio that could be conducive to participation in exercise. Applied interventions need to assist female students to ‘disengage’ from or overcome any perceived ‘unpleasantness’ of physical exertion during physical activity (decrease their perceived barriers, and to further highlight the multiple health and other benefits of regular exercising (increase their perceived

  20. A new technique for noise reduction at coronary CT angiography with multi-phase data-averaging and non-rigid image registration

    Energy Technology Data Exchange (ETDEWEB)

    Tatsugami, Fuminari; Higaki, Toru; Nakamura, Yuko; Yamagami, Takuji; Date, Shuji; Awai, Kazuo [Hiroshima University, Department of Diagnostic Radiology, Minami-ku, Hiroshima (Japan); Fujioka, Chikako; Kiguchi, Masao [Hiroshima University, Department of Radiology, Minami-ku, Hiroshima (Japan); Kihara, Yasuki [Hiroshima University, Department of Cardiovascular Medicine, Minami-ku, Hiroshima (Japan)

    2015-01-15

    To investigate the feasibility of a newly developed noise reduction technique at coronary CT angiography (CTA) that uses multi-phase data-averaging and non-rigid image registration. Sixty-five patients underwent coronary CTA with prospective ECG-triggering. The range of the phase window was set at 70-80 % of the R-R interval. First, three sets of consecutive volume data at 70 %, 75 % and 80 % of the R-R interval were prepared. Second, we applied non-rigid registration to align the 70 % and 80 % images to the 75 % image. Finally, we performed weighted averaging of the three images and generated a de-noised image. The image noise and contrast-to-noise ratio (CNR) in the proximal coronary arteries between the conventional 75 % and the de-noised images were compared. Two radiologists evaluated the image quality using a 5-point scale (1, poor; 5, excellent). On de-noised images, mean image noise was significantly lower than on conventional 75 % images (18.3 HU ± 2.6 vs. 23.0 HU ± 3.3, P < 0.01) and the CNR was significantly higher (P < 0.01). The mean image quality score for conventional 75 % and de-noised images was 3.9 and 4.4, respectively (P < 0.01). Our method reduces image noise and improves image quality at coronary CTA. (orig.)

  1. 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

  2. Shot noise and electronic properties in the inversion-symmetric Weyl semimetal resonant structure

    Science.gov (United States)

    Yang, Yanling; Bai, Chunxu; Xu, Xiaoguang; Jiang, Yong

    2018-02-01

    Using the transfer matrix method, the authors combine the analytical formula with numerical calculation to explore the shot noise and conductance of massless Weyl fermions in the Weyl semimetal resonant junction. By varying the barrier strength, the structure of the junction, the Fermi energy, and the crystallographic angle, the shot noise and conductance can be tuned efficiently. For a quasiperiodic superlattice, in complete contrast to the conventional junction case, the effect of the disorder strength on the shot noise and conductance depends on the competition of classical tunneling and Klein tunneling. Moreover, the delta barrier structure is also vital in determining the shot noise and conductance. In particular, a universal Fano factor has been found in a single delta potential case, whereas the resonant structure of the Fano factor perfectly matches with the number of barriers in a delta potential superlattice. These results are crucial for engineering nanoelectronic devices based on this topological semimetal material.

  3. On signal design by the R/0/ criterion for non-white Gaussian noise channels

    Science.gov (United States)

    Bordelon, D. L.

    1977-01-01

    The use of the cut-off rate criterion for modulation system design is investigated for channels with non-white Gaussian noise. A signal space representation of the waveform channel is developed, and the cut-off rate for vector channels with additive non-white Gaussian noise and unquantized demodulation is derived. When the signal input to the channel is a continuous random vector, maximization of the cut-off rate with constrained average signal energy leads to a water-filling interpretation of optimal energy distribution in signal space. The necessary condition for a finite signal set to maximize the cut-off rate with constrained energy and an equally likely probability assignment of signal vectors is presented, and an algorithm is outlined for numerically computing the optimum signal set. As an example, the rectangular signal set which has the water-filling average energy distribution and the optimum rectangular set are compared.

  4. Stochastic resonance and stability for a stochastic metapopulation system subjected to non-Gaussian noise and multiplicative periodic signal

    International Nuclear Information System (INIS)

    Kang-Kang, Wang; Xian-Bin, Liu; Yu, Zhou

    2015-01-01

    In this paper, the stability and stochastic resonance (SR) phenomenon induced by the multiplicative periodic signal for a metapopulation system driven by the additive Gaussian noise, multiplicative non-Gaussian noise and noise correlation time is investigated. By using the fast descent method, unified colored noise approximation and McNamara and Wiesenfeld’s SR theory, the analytical expressions of the stationary probability distribution function and signal-to-noise ratio (SNR) are derived in the adiabatic limit. Via numerical calculations, each effect of the addictive noise intensity, the multiplicative noise intensity and the correlation time upon the steady state probability distribution function and the SNR is discussed, respectively. It is shown that multiplicative, additive noises and the departure parameter from the Gaussian noise can all destroy the stability of the population system. However, the noise correlation time can consolidate the stability of the system. On the other hand, the correlation time always plays an important role in motivating the SR and enhancing the SNR. Under different parameter conditions of the system, the multiplicative, additive noises and the departure parameter can not only excite SR phenomenon, but also restrain the SR phenomenon, which demonstrates the complexity of different noises upon the nonlinear system. (paper)

  5. Dynamics of non-Markovian exclusion processes

    International Nuclear Information System (INIS)

    Khoromskaia, Diana; Grosskinsky, Stefan; Harris, Rosemary J

    2014-01-01

    Driven diffusive systems are often used as simple discrete models of collective transport phenomena in physics, biology or social sciences. Restricting attention to one-dimensional geometries, the asymmetric simple exclusion process (ASEP) plays a paradigmatic role to describe noise-activated driven motion of entities subject to an excluded volume interaction and many variants have been studied in recent years. While in the standard ASEP the noise is Poissonian and the process is therefore Markovian, in many applications the statistics of the activating noise has a non-standard distribution with possible memory effects resulting from internal degrees of freedom or external sources. This leads to temporal correlations and can significantly affect the shape of the current-density relation as has been studied recently for a number of scenarios. In this paper we report a general framework to derive the fundamental diagram of ASEPs driven by non-Poissonian noise by using effectively only two simple quantities, viz., the mean residual lifetime of the jump distribution and a suitably defined temporal correlation length. We corroborate our results by detailed numerical studies for various noise statistics under periodic boundary conditions and discuss how our approach can be applied to more general driven diffusive systems. (paper)

  6. Dynamics of non-Markovian exclusion processes

    Science.gov (United States)

    Khoromskaia, Diana; Harris, Rosemary J.; Grosskinsky, Stefan

    2014-12-01

    Driven diffusive systems are often used as simple discrete models of collective transport phenomena in physics, biology or social sciences. Restricting attention to one-dimensional geometries, the asymmetric simple exclusion process (ASEP) plays a paradigmatic role to describe noise-activated driven motion of entities subject to an excluded volume interaction and many variants have been studied in recent years. While in the standard ASEP the noise is Poissonian and the process is therefore Markovian, in many applications the statistics of the activating noise has a non-standard distribution with possible memory effects resulting from internal degrees of freedom or external sources. This leads to temporal correlations and can significantly affect the shape of the current-density relation as has been studied recently for a number of scenarios. In this paper we report a general framework to derive the fundamental diagram of ASEPs driven by non-Poissonian noise by using effectively only two simple quantities, viz., the mean residual lifetime of the jump distribution and a suitably defined temporal correlation length. We corroborate our results by detailed numerical studies for various noise statistics under periodic boundary conditions and discuss how our approach can be applied to more general driven diffusive systems.

  7. 11th International Workshop on Railway Noise

    CERN Document Server

    Anderson, David; Gautier, Pierre-Etienne; Iida, Masanobu; Nelson, James; Thompson, David; Tielkes, Thorsten; Towers, David; Vos, Paul

    2015-01-01

    The book reports on the 11th International Workshop on Railway Noise, held on 9 – 13 September, 2013, in Uddevalla, Sweden. The event, which was jointly organized by the Competence Centre Chalmers Railway Mechanics (CHARMEC) and the Departments of Applied Mechanics and Applied Acoustics at Chalmers University of Technology in Gothenburg, Sweden, covered a broad range of topics in the field of railway noise and vibration, including: prospects, legal regulations and perceptions; wheel and rail noise; prediction, measurements and monitoring; ground-borne vibration; squeal noise and structure-borne noise; and aerodynamic noise generated by high-speed trains. Further topics included: resilient track forms; grinding, corrugation and roughness; and interior noise and sound barriers. This book, which consists of a collection of peer-reviewed papers originally submitted to the workshop, not only provides readers with an overview of the latest developments in the field, but also offers scientists and engineers essent...

  8. Bregman Cost for Non-Gaussian Noise

    DEFF Research Database (Denmark)

    Burger, Martin; Dong, Yiqiu; Sciacchitano, Federica

    estimator for the Bregman cost if the image is corrupted by Gaussian noise. In this work we extend this result to other noise models with log-concave likelihood density, by introducing two related Bregman cost functions for which the CM and the MAP estimates are proper Bayes estima-tors. Moreover, we also....... From a theoretical point of view it has been argued that the MAP estimate is only in an asymptotic sense a Bayes estimator for the uniform cost function, while the CM estimate is a Bayes estimator for the means squared cost function. Recently, it has been proven that the MAP estimate is a proper Bayes...

  9. Non-destructive inspection protocol for reinforced concrete barriers and bridge railings

    Energy Technology Data Exchange (ETDEWEB)

    Chintakunta, Satish R. [Engineering and Software Consultants, Inc., 14123 Robert Paris Ct., Chantilly, VA 20151 (United States); Boone, Shane D. [Federal Highway Administration, Turner Fairbank Highway Research Center, 6300 Georgetown Pike, McLean, VA 22101 (United States)

    2014-02-18

    Reinforced concrete highway barriers and bridge railings serve to prevent errant vehicles from departing the travel way at grade separations. Despite the important role that they play in maintaining safety and their ubiquitous nature, barrier inspection rarely moves beyond visual inspection. In August 2008, a tractor-trailer fatally departed William Preston Lane, Jr. Memorial Bridge after it dislodged a section of the bridge barrier. Investigations following the accident identified significant corrosion of the anchor bolts attaching the bridge railing to the bridge deck. As a result of the information gathered during its investigation of the accident, the National Transportation Safety Board (NTSB) made recommendations to the Federal Highway Administration concerning Non-Destructive Evaluation (NDE) of concrete bridge railings. The Center for nondestructive evaluation (NDE) at Turner Fairbank Highway Research Center in McLean, VA is currently evaluating feasibility of using four technologies - ground penetrating radar (GPR), ultrasonic pulse-echo, digital radiography and infrared thermal imaging methods to develop bridge inspection methods that augment visual inspections, offer reliable measurement techniques, and are practical, both in terms of time and cost, for field inspection work. Controlled samples containing predefined corrosion levels in reinforcing steel were embedded at barrier connection points for laboratory testing. All four NDE techniques were used in the initial phase I testing. An inspection protocol for detecting and measuring the corrosion of reinforced steel embedded in the anchorage system will be developed as part of phase II research. The identified technologies shall be further developed for field testing utilizing a structure with a barrier in good condition and a structure with a barrier in poor condition.

  10. Non-destructive inspection protocol for reinforced concrete barriers and bridge railings

    Science.gov (United States)

    Chintakunta, Satish R.; Boone, Shane D.

    2014-02-01

    Reinforced concrete highway barriers and bridge railings serve to prevent errant vehicles from departing the travel way at grade separations. Despite the important role that they play in maintaining safety and their ubiquitous nature, barrier inspection rarely moves beyond visual inspection. In August 2008, a tractor-trailer fatally departed William Preston Lane, Jr. Memorial Bridge after it dislodged a section of the bridge barrier. Investigations following the accident identified significant corrosion of the anchor bolts attaching the bridge railing to the bridge deck. As a result of the information gathered during its investigation of the accident, the National Transportation Safety Board (NTSB) made recommendations to the Federal Highway Administration concerning Non-Destructive Evaluation (NDE) of concrete bridge railings. The Center for nondestructive evaluation (NDE) at Turner Fairbank Highway Research Center in McLean, VA is currently evaluating feasibility of using four technologies - ground penetrating radar (GPR), ultrasonic pulse-echo, digital radiography and infrared thermal imaging methods to develop bridge inspection methods that augment visual inspections, offer reliable measurement techniques, and are practical, both in terms of time and cost, for field inspection work. Controlled samples containing predefined corrosion levels in reinforcing steel were embedded at barrier connection points for laboratory testing. All four NDE techniques were used in the initial phase I testing. An inspection protocol for detecting and measuring the corrosion of reinforced steel embedded in the anchorage system will be developed as part of phase II research. The identified technologies shall be further developed for field testing utilizing a structure with a barrier in good condition and a structure with a barrier in poor condition.

  11. Non-standard quantum groups and superization

    Energy Technology Data Exchange (ETDEWEB)

    Majid, S. [Cambridge Univ. (United Kingdom). Dept. of Applied Mathematics and Theoretical Physics (DAMTP); Rodriguez-Plaza, M.J. [Nationaal Inst. voor Kernfysica en Hoge-Energiefysica (NIKHEF), Amsterdam (Netherlands). Sectie H

    1995-12-31

    We obtain the universal R-matrix of the non-standard quantum group associated to the Alexander-Conway knot polynomial. We show further that this nonstandard quantum group is related to the super-quantum group U{sub q}gl(1 vertical stroke 1) by a general process of superization, which we describe. We also study a twisted variant of this non-standard quantum group and obtain, as a result, a twisted version uf U{sub q}gl(1 vertical stroke 1) as a q-supersymmetry of the exterior differential calculus of any quantum plane of Hecke type, acting by mixing the bosonic x{sub i} co-ordinates and the forms dx{sub i}. (orig.).

  12. Noise-induced effects in population dynamics

    Science.gov (United States)

    Spagnolo, Bernardo; Cirone, Markus; La Barbera, Antonino; de Pasquale, Ferdinando

    2002-03-01

    We investigate the role of noise in the nonlinear relaxation of two ecosystems described by generalized Lotka-Volterra equations in the presence of multiplicative noise. Specifically we study two cases: (i) an ecosystem with two interacting species in the presence of periodic driving; (ii) an ecosystem with a great number of interacting species with random interaction matrix. We analyse the interplay between noise and periodic modulation for case (i) and the role of the noise in the transient dynamics of the ecosystem in the presence of an absorbing barrier in case (ii). We find that the presence of noise is responsible for the generation of temporal oscillations and for the appearance of spatial patterns in the first case. In the other case we obtain the asymptotic behaviour of the time average of the ith population and discuss the effect of the noise on the probability distributions of the population and of the local field.

  13. Quantitative analysis of LISA pathfinder test-mass noise

    International Nuclear Information System (INIS)

    Ferraioli, Luigi; Congedo, Giuseppe; Hueller, Mauro; Vitale, Stefano; Hewitson, Martin; Nofrarias, Miquel; Armano, Michele

    2011-01-01

    LISA Pathfinder (LPF) is a mission aiming to test the critical technology for the forthcoming space-based gravitational-wave detectors. The main scientific objective of the LPF mission is to demonstrate test masses free falling with residual accelerations below 3x10 -14 m s -2 /√(Hz) at 1 mHz. Reaching such an ambitious target will require a significant amount of system optimization and characterization, which will in turn require accurate and quantitative noise analysis procedures. In this paper, we discuss two main problems associated with the analysis of the data from LPF: i) excess noise detection and ii) noise parameter identification. The mission is focused on the low-frequency region ([0.1, 10] mHz) of the available signal spectrum. In such a region, the signal is dominated by the force noise acting on test masses. At the same time, the mission duration is limited to 90 days and typical data segments will be 24 hours in length. Considering those constraints, noise analysis is expected to deal with a limited amount of non-Gaussian data, since the spectrum statistics will be far from Gaussian and the lowest available frequency is limited by the data length. In this paper, we analyze the details of the expected statistics for spectral data and develop two suitable excess noise estimators. One is based on the statistical properties of the integrated spectrum, the other is based on the Kolmogorov-Smirnov test. The sensitivity of the estimators is discussed theoretically for independent data, then the algorithms are tested on LPF synthetic data. The test on realistic LPF data allows the effect of spectral data correlations on the efficiency of the different noise excess estimators to be highlighted. It also reveals the versatility of the Kolmogorov-Smirnov approach, which can be adapted to provide reasonable results on correlated data from a modified version of the standard equations for the inversion of the test statistic. Closely related to excess noise

  14. LOW-NOISE PAVEMENT AS A WAY OF LIMITATION OF TRAFFIC NOISE LEVEL

    Directory of Open Access Journals (Sweden)

    Władysław Gardziejczyk

    2014-11-01

    Full Text Available Road surface can significantlyreduce the trafficnoise level. Depending on the characteristic of the upper surface layers the differences between the maximum rolling noise levels from passing vehicles to reach values about 10 dB (A. A special group is low-noise pavements characterized by the presence of voids above 15%. Application the porous asphalt layers or asphalt mixture type BBTM affects a significantreduction the width of land surrounded the roads where permissible equivalent sound level is exceeded. Such solutions in some cases can replace acoustic barriers. Road pavements with a higher content of voids require proper maintenance because their acoustic performances are reduced during operation.

  15. Noise spectrum of quantum transport through double quantum dots: Renormalization and non-Markovian effects

    Directory of Open Access Journals (Sweden)

    Pengqin Shi

    2016-09-01

    Full Text Available Based on the time-nonlocal particle number-resolved master equation, we investigate the sequential electron transport through the interacting double quantum dots. Our calculations show that there exists the effect of energy renormalization in the dispersion of the bath interaction spectrum and it is sensitive to the the bandwidth of the bath. This effect would strongly affect the stationary current and its zero-frequency shot noise for weak inter-dot coherent coupling strength, but for strong inter-dot coupling regime, it is negligible due to the strong intrinsic Rabi coherent dynamics. Moreover, the possible observable effects of the energy renormalization in the noise spectrum are also investigated through the Rabi coherence signal. Finally, the non-Markovian effect is manifested in the finite-frequency noise spectrum with the appearance of quasisteps, and the magnitude of these quasisteps are modified by the dispersion function.

  16. Noise characterization of enhancement-mode AlGaN graded barrier MIS-HEMT devices

    Science.gov (United States)

    Mohanbabu, A.; Saravana Kumar, R.; Mohankumar, N.

    2017-12-01

    This paper reports a systematic theoretical study on the microwave noise performance of graded AlGaN/GaN metal-insulator semiconductor high-electron mobility transistors (MIS-HEMTs) built on an Al2O3 substrate. The HfAlOx/AlGaN/GaN MIS-HEMT devices designed for this study show an outstanding small signal analog/RF and noise performance. The results on 1 μm gate length device show an enhancement mode operation with threshold voltage, VT = + 5.3 V, low drain leakage current, Ids,LL in the order of 1 × 10-9 A/mm along with high current gain cut-off frequency, fT of 17 GHz and maximum oscillation frequency fmax of 47 GHz at Vds = 10 V. The device Isbnd V and low-frequency noise estimation of the gate and drain noise spectral density and their correlation are evaluated using a Green's function method under different biasing conditions. The devices show a minimum noise figure (NFmin) of 1.053 dB in combination with equivalent noise resistance (Rn) of 23 Ω at 17 GHz, at Vgs = 6 V and Vds = 5 V which is relatively low and is suitable for broad-band low-noise amplifiers. This study shows that the graded AlGaN MIS-HEMT with HfAlOX gate insulator is appropriate for application requiring high-power and low-noise.

  17. Control system architecture: The standard and non-standard models

    International Nuclear Information System (INIS)

    Thuot, M.E.; Dalesio, L.R.

    1993-01-01

    Control system architecture development has followed the advances in computer technology through mainframes to minicomputers to micros and workstations. This technology advance and increasingly challenging accelerator data acquisition and automation requirements have driven control system architecture development. In summarizing the progress of control system architecture at the last International Conference on Accelerator and Large Experimental Physics Control Systems (ICALEPCS) B. Kuiper asserted that the system architecture issue was resolved and presented a ''standard model''. The ''standard model'' consists of a local area network (Ethernet or FDDI) providing communication between front end microcomputers, connected to the accelerator, and workstations, providing the operator interface and computational support. Although this model represents many present designs, there are exceptions including reflected memory and hierarchical architectures driven by requirements for widely dispersed, large channel count or tightly coupled systems. This paper describes the performance characteristics and features of the ''standard model'' to determine if the requirements of ''non-standard'' architectures can be met. Several possible extensions to the ''standard model'' are suggested including software as well as the hardware architectural feature

  18. Finite-difference time-domain simulation of thermal noise in open cavities

    International Nuclear Information System (INIS)

    Andreasen, Jonathan; Cao Hui; Taflove, Allen; Kumar, Prem; Cao Changqi

    2008-01-01

    A numerical model based on the finite-difference time-domain (FDTD) method is developed to simulate thermal noise in open cavities owing to output coupling. The absorbing boundary of the FDTD grid is treated as a blackbody, whose thermal radiation penetrates the cavity in the grid. The calculated amount of thermal noise in a one-dimensional dielectric cavity recovers the standard result of the quantum Langevin equation in the Markovian regime. Our FDTD simulation also demonstrates that in the non-Markovian regime the buildup of the intracavity noise field depends on the ratio of the cavity photon lifetime to the coherence time of thermal radiation. The advantage of our numerical method is that the thermal noise is introduced in the time domain without prior knowledge of cavity modes

  19. DOE technical standards list: Directory of DOE and contractor personnel involved in non-government standards activities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-05-01

    The body of this document contains a listing of DOE employees and DOE contractors who have submitted form DOE F 1300.2, Record of Non-Government Standards Activity, which is attached to the end of this document. Additional names were added from rosters supplied by non-Government standards bodies. The committees or governing bodies in which the person participates is listed after each name. An asterisk preceding the committee notation indicates that the person has identified himself or herself as the DOE representative on that committee. Appendices to this document are also provided to sort the information by the parent employment organization, by non-Government standards activity, and by the proper names of the non-Government standards organizations and committees. DOE employees and contractors listed in this technical standards list are those recorded as of May 1, 1999.

  20. Shot Noise in Negative-Differential-Conductance Devices

    National Research Council Canada - National Science Library

    Song, W

    2003-01-01

    The authors have compared the shot-noise properties at T = 4.2 K of a double-barrier resonant-tunneling diode and a superlattice tunnel diode, both of which exhibit negative differential-conductance (NDC...

  1. A novel method to remove GPR background noise based on the similarity of non-neighboring regions

    Science.gov (United States)

    Montiel-Zafra, V.; Canadas-Quesada, F. J.; Vera-Candeas, P.; Ruiz-Reyes, N.; Rey, J.; Martinez, J.

    2017-09-01

    Ground penetrating radar (GPR) is a non-destructive technique that has been widely used in many areas of research, such as landmine detection or subsurface anomalies, where it is required to locate targets embedded within a background medium. One of the major challenges in the research of GPR data remains the improvement of the image quality of stone materials by means of detection of true anisotropies since most of the errors are caused by an incorrect interpretation by the users. However, it is complicated due to the interference of the horizontal background noise, e.g., the air-ground interface, that reduces the high-resolution quality of radargrams. Thus, weak or deep anisotropies are often masked by this type of noise. In order to remove the background noise obtained by GPR, this work proposes a novel background removal method assuming that the horizontal noise shows repetitive two-dimensional regions along the movement of the GPR antenna. Specifically, the proposed method, based on the non-local similarity of regions over the distance, computes similarities between different regions of the same depth in order to identify most repetitive regions using a criterion to avoid closer regions. Evaluations are performed using a set of synthetic and real GPR data. Experimental results show that the proposed method obtains promising results compared to the classic background removal techniques and the most recently published background removal methods.

  2. Effects of non-standard interactions in the MINOS experiment

    International Nuclear Information System (INIS)

    Blennow, Mattias; Ohlsson, Tommy; Skrotzki, Julian

    2008-01-01

    We investigate the effects of non-standard interactions on the determination of the neutrino oscillation parameters Δm 31 2 , θ 23 , and θ 13 in the MINOS experiment. We show that adding non-standard interactions to the analysis lead to an extension of the allowed parameter space to larger values of Δm 31 2 and smaller θ 23 , and basically removes all predictability for θ 13 . In addition, we discuss the sensitivities to the non-standard interaction parameters of the MINOS experiment alone. In particular, we examine the degeneracy between θ 13 and the non-standard interaction parameter ε eτ . We find that this degeneracy is responsible for the removal of the θ 13 predictability and that the possible bound on |ε eτ | is competitive with direct bounds only if a more stringent external bound on θ 13 is applied

  3. Field evaluation of vegetation and noise barriers for mitigation of near-freeway air pollution under variable wind conditions

    Science.gov (United States)

    Lee, Eon S.; Ranasinghe, Dilhara R.; Ahangar, Faraz Enayati; Amini, Seyedmorteza; Mara, Steven; Choi, Wonsik; Paulson, Suzanne; Zhu, Yifang

    2018-02-01

    Traffic-related air pollutants are a significant public health concern, particularly near freeways. Previous studies have suggested either soundwall or vegetation barriers might reduce the near-freeway air pollution. This study aims to investigate the effectiveness of a combination of both soundwall and vegetation barrier for reducing ultrafine particles (UFPs, diameter ≤ 100 nm) and PM2.5 (diameter ≤ 2.5 μm) concentrations. Concurrent data collection was carried out at both upwind and downwind fixed locations approximately 10-15 m away from the edge of two major freeways in California. This study observed that the reduction of UFP and PM2.5 was generally greater with the combination barrier than with either soundwall or vegetation alone. Since there were no non-barrier sites at the study locations, the reductions reported here are all in relative terms. The soundwall barrier was more effective for reducing PM2.5 (25-53%) than UFPs (0-5%), and was most effective (51-53% for PM2.5) when the wind speed ranged between 1 and 2 m/s. Under the same range of wind speed, the vegetation barrier had little effect (0-5%) on reducing PM2.5; but was effective at reducing UFP (up to 50%). For both types of roadside barrier, decreasing wind speed resulted in greater net reduction of UFPs (i.e., total number particle concentrations; inversely proportional). This trend was observed, however, only within specific particle size ranges (i.e., diameter pollution mitigation.

  4. The standard model on non-commutative space-time

    International Nuclear Information System (INIS)

    Calmet, X.; Jurco, B.; Schupp, P.; Wohlgenannt, M.; Wess, J.

    2002-01-01

    We consider the standard model on a non-commutative space and expand the action in the non-commutativity parameter θ μν . No new particles are introduced; the structure group is SU(3) x SU(2) x U(1). We derive the leading order action. At zeroth order the action coincides with the ordinary standard model. At leading order in θ μν we find new vertices which are absent in the standard model on commutative space-time. The most striking features are couplings between quarks, gluons and electroweak bosons and many new vertices in the charged and neutral currents. We find that parity is violated in non-commutative QCD. The Higgs mechanism can be applied. QED is not deformed in the minimal version of the NCSM to the order considered. (orig.)

  5. Colored thermal noise driven dynamical system in the presence and absence of non-equilibrium constraint: time dependence of information entropy flux and entropy production

    International Nuclear Information System (INIS)

    Goswami, Gurupada; Mukherjee, Biswajit; Bag, Bidhan Chandra

    2005-01-01

    We have studied the relaxation of non-Markovian and thermodynamically closed system both in the absence and presence of non-equilibrium constraint in terms of the information entropy flux and entropy production based on the Fokker-Planck and the entropy balance equations. Our calculation shows how the relaxation time depends on noise correlation time. It also considers how the non-equilibrium constraint is affected by system parameters such as noise correlation time, strength of dissipation and frequency of dynamical system. The interplay of non-equilibrium constraint, frictional memory kernel, noise correlation time and frequency of dynamical system reveals the extremum nature of the entropy production

  6. Colored thermal noise driven dynamical system in the presence and absence of non-equilibrium constraint: time dependence of information entropy flux and entropy production

    Science.gov (United States)

    Goswami, Gurupada; Mukherjee, Biswajit; Bag, Bidhan Chandra

    2005-06-01

    We have studied the relaxation of non-Markovian and thermodynamically closed system both in the absence and presence of non-equilibrium constraint in terms of the information entropy flux and entropy production based on the Fokker-Planck and the entropy balance equations. Our calculation shows how the relaxation time depends on noise correlation time. It also considers how the non-equilibrium constraint is affected by system parameters such as noise correlation time, strength of dissipation and frequency of dynamical system. The interplay of non-equilibrium constraint, frictional memory kernel, noise correlation time and frequency of dynamical system reveals the extremum nature of the entropy production.

  7. Transistor design considerations for low-noise preamplifiers

    International Nuclear Information System (INIS)

    Fair, R.B.

    1976-01-01

    A review is presented of design considerations for GaAs Schottky-barrier FETs and other types of transistors in low-noise amplifiers for capacitive sources which are used in nuclear radiation detectors and high speed fiber-optic communication systems. Ultimate limits on performance are evaluated in terms of the g/sub m//C/sub i/ ratio and the gate leakage current to minimize the noise sources. Si bipolar transistors and the future prospects of GaAs, Si and InAs MISFETs are discussed, and performance is compared to FETs currently being used in low-noise preamplifiers

  8. The GEOFAR Project - Geothermal Finance and Awareness in Europeans Regions - Development of new schemes to overcome non-technical barriers, focusing particularly on financial barriers

    Science.gov (United States)

    Poux, Adeline; Wendel, Marco; Jaudin, Florence; Hiegl, Mathias

    2010-05-01

    Numerous advantages of geothermal energy like its widespread distribution, a base-load power and availability higher than 90%, a small footprint and low carbon emissions, and the growing concerns about climate changes strongly promote the development of geothermal projects. Geothermal energy as a local energy source implies needs on surface to be located close to the geothermal resource. Many European regions dispose of a good geothermal potential but it is mostly not sufficiently developed due to non-technical barriers occurring at the very early stages of the project. The GEOFAR Project carried out within the framework of EU's "Intelligent Energy Europe" (IEE) program, gathers a consortium of European partners from Germany, France, Greece, Spain and Portugal. Launched in September 2008, the aim of this research project is to analyze the mentioned non-technical barriers, focusing most particularly on economic and financial aspects. Based on this analysis GEOFAR aims at developing new financial and administrative schemes to overcome the main financial barriers for deep geothermal projects (for electricity and direct use, without heat pumps). The analysis of the current situation and the future development of geothermal energy in GEOFAR target countries (Germany, France, Greece, Spain, Portugal, Slovakia, Bulgaria and Hungary) was necessary to understand and expose the diverging status of the geothermal sector and the more and less complicated situation for geothermal projects in different Europeans Regions. A deeper analysis of 40 cases studies (operating, planned and failed projects) of deep geothermal projects also contributed to this detailed view. An exhaustive analysis and description of financial mechanisms already existing in different European countries and at European level to support investors completed the research on non-technical barriers. Based on this profound analysis, the GEOFAR project has made an overview of the difficulties met by project

  9. Auditory and Non-Auditory Contributions for Unaided Speech Recognition in Noise as a Function of Hearing Aid Use

    OpenAIRE

    Gieseler, Anja; Tahden, Maike A. S.; Thiel, Christiane M.; Wagener, Kirsten C.; Meis, Markus; Colonius, Hans

    2017-01-01

    Differences in understanding speech in noise among hearing-impaired individuals cannot be explained entirely by hearing thresholds alone, suggesting the contribution of other factors beyond standard auditory ones as derived from the audiogram. This paper reports two analyses addressing individual differences in the explanation of unaided speech-in-noise performance among n = 438 elderly hearing-impaired listeners (mean = 71.1 ± 5.8 years). The main analysis was designed to identify clinically...

  10. A comparison of barriers to mental health support-seeking among farming and non-farming adults in rural South Australia.

    Science.gov (United States)

    Hull, Melissa J; Fennell, Kate M; Vallury, Kari; Jones, Martin; Dollman, James

    2017-12-01

    To assess the differences between farming and non-farming rural adults in perceived barriers to mental health service use. A cross-sectional survey, modified from the Barriers to Help-Seeking Scale (BHSS), was conducted using a computer-assisted telephone interview. Respondents (age 52.6 ± 11.6 years) were recruited from three rural regions of South Australia. Approximately, 78 non-farmers and 45 farmers were included in analyses. 78 retired and two unemployed participants were excluded from the analyses. Farmers and non-farmers were compared on domain scores and individual item responses from the adapted BHSS that represent 'agrarian' attitudes to support-seeking for mental health: stoicism, self-reliance, minimisation of the problem, stigma and distrust of health professionals. In the analysis of domain scores, 'Need for Control and Self-Reliance' was a stronger barrier for farmers than non-farmers (P = 0.009) with a trend (P = 0.07) towards stronger barriers among farmers in the 'Minimising Problem and Resignation' domain. In the analysis of item-level responses, there was a difference (P = 0.03) between farmers and non-farmers in responses to 'I find it difficult to understand my doctor/health professional', with 24.4% of the farmers agreeing that this is a barrier compared with 15.3% of the non-farmers. Long-held stereotypes of stoicism and self-reliance among farmers were somewhat supported, in the context of mental health. Mental health services and professionals in rural Australia might need to adapt their practices to successfully engage this population. © 2017 National Rural Health Alliance Inc.

  11. 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)

  12. Sustainability and EMAS: Impact of Motivations and Barriers on the Perceived Benefits from the Adoption of Standards

    Directory of Open Access Journals (Sweden)

    José Álvarez-García

    2016-10-01

    Full Text Available The objective of this paper is to analyze the influence of the sources of motivation that lead companies to adopt a global standard of the Environmental Management System and the barriers found in the process, on the perceived benefits of the implementation and certification of the standard. To achieve the objectives proposed, primary data were collected using a survey questionnaire that was administered to a representative sample of companies certified as EMAS-Eco-Management and Audit Scheme of the Autonomous Community of Galicia (sample of 114 of the 255 companies. An extensive review of the academic literature published on ISO 14001 and EMAS about motivations, barriers and benefits was carried out in order to establish the working hypotheses that are analyzed using structural equation models as the statistical tool. The findings of this study show that the motivations positively affect the benefits derived from implementation, noting that the internal motivations (related to efficiency; improved performance, productivity and profitability have a stronger influence on the benefits than the external motivations (related to stakeholders’ social pressure. In addition, the motivations also affect the perceived barriers, and these affect the benefits negatively, i.e., the higher the barriers encountered, the lower the perceived benefits. The results obtained allow us to identify important implications for managers, which will help them establish management strategies in the field of environmental management.

  13. Resonant activation in 2D and 3D systems driven by multi-variate Lévy noise

    International Nuclear Information System (INIS)

    Szczepaniec, Krzysztof; Dybiec, Bartłomiej

    2014-01-01

    Resonant activation is one of the classical effects demonstrating the constructive role of noise. In resonant activation, the cooperative action of a barrier modulation process and noise lead to the optimal escape kinetics as measured by the mean first passage time. Resonant activation has been observed in versatile systems for various types of barrier modulation process and noise type. Here, we show that resonant activation is also observed in 2D and 3D systems driven by bi-variate and tri-variate α-stable noise. The strength of resonant activation is sensitive to the exact value of the noise parameters. In particular, the decrease in the stability index α results in the disappearance of the resonant activation. (paper)

  14. The Use of Noise Dampening Mats to Reduce Heavy-Equipment Noise Exposures in Construction

    Directory of Open Access Journals (Sweden)

    Sabah Saleh

    2017-06-01

    Full Text Available The performance of sound barriers was evaluated to determine their technical effectiveness and practicality in reducing noise exposures to operating engineers in construction. Commercially purchased sound dampening mats (SDMats were installed inside three heavy-equipment engine compartments. Sound pressure levels (SPLs were measured before and after installing the SDMats while the equipment was on idle and full-throttle settings where it normally operates. SPLs inside the heavy-equipment operator cabs were significantly reduced by 5.6–7.6 dBA on the full-throttle setting following installation of the SDMats (p<0.01. The evaluated engineering control intervention was simple to install, affordable, and substantially reduced the engine noise reaching the heavy-equipment operator, potentially reducing reliance on hearing-protection devices to protect construction workers from noise exposures.

  15. Boltzmann-distribution-equivalent for Lévy noise and how it leads to thermodynamically consistent epicatalysis

    Science.gov (United States)

    Bier, Martin

    2018-02-01

    Nonequilibrium systems commonly exhibit Lévy noise. This means that the distribution for the size of the Brownian fluctuations has a "fat" power-law tail. Large Brownian kicks are then more common as compared to the ordinary Gaussian distribution. We consider a two-state system, i.e., two wells and a barrier in between. The barrier is sufficiently high for a barrier crossing to be a rare event. When the noise is Lévy, we do not get a Boltzmann distribution between the two wells. Instead we get a situation where the distribution between the two wells also depends on the height of the barrier that is in between. Ordinarily, a catalyst, by lowering the barrier between two states, speeds up the relaxation to an equilibrium, but does not change the equilibrium distribution. In an environment with Lévy noise, on the other hand, we have the possibility of epicatalysis, i.e., a catalyst effectively altering the distribution between two states through the changing of the barrier height. After deriving formulas to quantitatively describe this effect, we discuss how this idea may apply in nuclear reactors and in the biochemistry of a living cell.

  16. SOUND FIELD DIFFUSIVITY AT THE TOP SURFACE OF SCHROEDER DIFFUSER BARRIERS

    OpenAIRE

    M. R. Monazzam

    2006-01-01

    Reactive barriers are one of the most promising and novel environmental noise barriers. In this case using Schroeder diffusers (e.g. quadratic residue diffusers) on the top surface of the T-shape barrier was shown to significantly improve the performance of absorbent T-shape barriers. The reasons behind the high performance of diffuser barriers are considered in this investigation. A question about the diffusivity behavior of Schroeder diffusers when they are utilized on the top of barrier wa...

  17. Noise Diagnostics of Stationary and Non-Stationary Reactor Processes

    Energy Technology Data Exchange (ETDEWEB)

    Sunde, Carl

    2007-04-15

    This thesis concerns the application of noise diagnostics on different problems in the area of reactor physics involving both stationary and non-stationary core processes. Five different problems are treated, divided into three different parts. The first problem treated in the first part is the classification of two-phase flow regimes from neutron radiographic and visible light images with a neuro-wavelet algorithm. The algorithm consists of wavelet pre-processing and of an artificial neural network. The result indicates that the wavelet pre-processing is improving the training of the neural network. Next, detector tubes which are suspected of impacting on nearby fuel-assemblies in a boiling water reactor (BWR) are identified by both a classical spectral method and wavelet-based methods. It was found that there is good agreement between the different methods as well as with visual inspections of detector tube and fuel assembly damage made during the outage at the plant. The third problem addresses the determination of the decay ratio of a BWR from the auto-correlation function (ACF). Here wavelets are used, with some success, both for de-trending and de-nosing of the ACF and also for direct estimation of the decay ratio from the ACF. The second part deals with the analysis of beam-mode and shell-mode core-barrel vibrations in pressurised water reactors (PWRs). The beam-mode vibrations are analysed by using parameters of the vibration peaks, in spectra from ex core detectors. A trend analysis of the peak amplitude shows that the peak amplitude is changing during the fuel cycle. When it comes to the analysis of the shell-mode vibration, 1-D analytical and numerical calculations are performed in order to calculate the neutron noise induced in the core. The two calculations are in agreement and show that a large local noise component is present in the core which could be used to classify the shell-mode vibrations. However, a measurement made in the PWR Ringhals-3 shows

  18. Noise Diagnostics of Stationary and Non-Stationary Reactor Processes

    International Nuclear Information System (INIS)

    Sunde, Carl

    2007-01-01

    This thesis concerns the application of noise diagnostics on different problems in the area of reactor physics involving both stationary and non-stationary core processes. Five different problems are treated, divided into three different parts. The first problem treated in the first part is the classification of two-phase flow regimes from neutron radiographic and visible light images with a neuro-wavelet algorithm. The algorithm consists of wavelet pre-processing and of an artificial neural network. The result indicates that the wavelet pre-processing is improving the training of the neural network. Next, detector tubes which are suspected of impacting on nearby fuel-assemblies in a boiling water reactor (BWR) are identified by both a classical spectral method and wavelet-based methods. It was found that there is good agreement between the different methods as well as with visual inspections of detector tube and fuel assembly damage made during the outage at the plant. The third problem addresses the determination of the decay ratio of a BWR from the auto-correlation function (ACF). Here wavelets are used, with some success, both for de-trending and de-nosing of the ACF and also for direct estimation of the decay ratio from the ACF. The second part deals with the analysis of beam-mode and shell-mode core-barrel vibrations in pressurised water reactors (PWRs). The beam-mode vibrations are analysed by using parameters of the vibration peaks, in spectra from ex core detectors. A trend analysis of the peak amplitude shows that the peak amplitude is changing during the fuel cycle. When it comes to the analysis of the shell-mode vibration, 1-D analytical and numerical calculations are performed in order to calculate the neutron noise induced in the core. The two calculations are in agreement and show that a large local noise component is present in the core which could be used to classify the shell-mode vibrations. However, a measurement made in the PWR Ringhals-3 shows

  19. Non-verbal communication barriers when dealing with Saudi sellers

    Directory of Open Access Journals (Sweden)

    Yosra Missaoui

    2015-12-01

    Full Text Available Communication has a major impact on how customers perceive sellers and their organizations. Especially, the non-verbal communication such as body language, appearance, facial expressions, gestures, proximity, posture, eye contact that can influence positively or negatively the first impression of customers and their experiences in stores. Salespeople in many countries, especially the developing ones, are just telling about their companies’ products because they are unaware of the real role of sellers and the importance of non-verbal communication. In Saudi Arabia, the seller profession has been exclusively for foreign labor until 2006. It is very recently that Saudi workforce enters to the retailing sector as sellers. The non-verbal communication of those sellers has never been evaluated from consumer’s point of view. Therefore, the aim of this paper is to explore the non-verbal communication barriers that customers are facing when dealing with Saudi sellers. After discussing the non-verbal communication skills that sellers must have in the light of the previous academic research and the depth interviews with seven focus groups of Saudi customers, this study found that the Saudi customers were not totally satisfied with the current non-verbal communication skills of Saudi sellers. Therefore, it is strongly recommended to develop the non-verbal communication skills of Saudi sellers by intensive trainings, to distinguish more the appearance of their sellers, especially the female ones, to focus on the time of intervention as well as the proximity to customers.

  20. Self-noise in interferometers - radio and infrared

    International Nuclear Information System (INIS)

    Kulkarni, S.R.

    1989-01-01

    A complete theory of noise in a synthesis image is proposed for a source of arbitrary strength. In the limit of faint sources, the standard estimates of noise in a synthesis image are recovered, while in the limit of strong sources, the noise in the synthesis image is found to be dominated by either self noise or by the noise generated by the source signal itself. It is found that the best VLBI maps (with noise approaching the thermal noise) may in fact be limited by self noise, and that there is a negligible bias in the standard definitions of the bispectrum phasor and the closure phase. The results suggest that at the low signal levels which are characteristic of infrared interferometers, it is best to fit the model to all the closure phases and fringe amplitudes. 13 refs

  1. The standard model on non-commutative space-time

    Energy Technology Data Exchange (ETDEWEB)

    Calmet, X.; Jurco, B.; Schupp, P.; Wohlgenannt, M. [Sektion Physik, Universitaet Muenchen (Germany); Wess, J. [Sektion Physik, Universitaet Muenchen (Germany); Max-Planck-Institut fuer Physik, Muenchen (Germany)

    2002-03-01

    We consider the standard model on a non-commutative space and expand the action in the non-commutativity parameter {theta}{sup {mu}}{sup {nu}}. No new particles are introduced; the structure group is SU(3) x SU(2) x U(1). We derive the leading order action. At zeroth order the action coincides with the ordinary standard model. At leading order in {theta}{sup {mu}}{sup {nu}} we find new vertices which are absent in the standard model on commutative space-time. The most striking features are couplings between quarks, gluons and electroweak bosons and many new vertices in the charged and neutral currents. We find that parity is violated in non-commutative QCD. The Higgs mechanism can be applied. QED is not deformed in the minimal version of the NCSM to the order considered. (orig.)

  2. STUDY NOISE POLLUTION TYUMEN USING GIS

    Directory of Open Access Journals (Sweden)

    V. A. Dobryakova

    2016-01-01

    Full Text Available One of the most harmful factors of environment of the city is the noise, and its weight among the factors adversely affecting the life and health of the population has been increasing steadily [Sheina and etc., 2007; Polovinkina and etc., 2012]. Today, most major cities of the Russian Federation (70% have a high noise pollution problem. The system of support for the monitoring and control of acoustic situation in the city can be considered noise pollution electronic cards made using geographic information systems (GIS. There are two fundamentally different approaches to the selection of software for creation of noise maps. According to the first of them, use universal multifunctional complexes GIS (ArcGIS, MapInfo. According to the distribution of data points on the noise characteristics is created TIN model. A second approach to create noise maps using highly specialized software (MapNoise, SoundPLAN, Mitha, Cadna, ExNOISE et al.. To calculate noise propagation area is divided on the grid with a certain step, the most relevant mapping purposes. Calculation of noise levels is carried out in a grid cell by measurements based on diffraction and reflection of sound barriers and absorbing underlying surface. Noise pollution is also displayed using contour lines.

  3. Existing Noise Level at Railway Stations in Malaysia

    Directory of Open Access Journals (Sweden)

    Shahidan Shahiron

    2017-01-01

    Full Text Available Railway transportation known as one of the most environmental friendly transportation mode. However, the significance problems of railway transportation are noise pollution and negatively impact the wellbeing of the whole community. Unfortunately, there has been lack of public awareness about the noise level produce by the railway transportation in Malaysia. This study investigates the noise level produced by railway transportation in Malaysia specifically by Keretapi Tanah Melayu Berhad (KTMB. Methods of collecting existing noise level at railway stations in Malaysia are briefly discussed in this study. The finding indicates that the noise level produced by the railway transportation in Malaysia which is by KTMB is considered as dangerous to human being and also exceed the noise limit that has been assigned by Department of Environment Ministry of Natural Resources and Environment of Malaysia. A better noise barrier and improved material should be developed to mitigate the existing noise level produced by railway transportations in Malaysia.

  4. Wind Noise Reduction in a Non-Porous Subsurface Windscreen

    Science.gov (United States)

    Zuckerwar, Allan J.; Shams, Qamar A.; Knight, H. Keith

    2012-01-01

    Measurements of wind noise reduction were conducted on a box-shaped, subsurface windscreen made of closed cell polyurethane foam. The windscreen was installed in the ground with the lid flush with the ground surface. The wind was generated by means of a fan, situated on the ground, and the wind speed was measured at the center of the windscreen lid with an ultrasonic anemometer. The wind speed was controlled by moving the fan to selected distances from the windscreen. The wind noise was measured on a PCB Piezotronics 3†electret microphone. Wind noise spectra were measured with the microphone exposed directly to the wind (atop the windscreen lid) and with the microphone installed inside the windscreen. The difference between the two spectra comprises the wind noise reduction. At wind speeds of 3, 5, and 7 m/s, the wind noise reduction is typically 15 dB over the frequency range of 0.1-20 Hz.

  5. Noise Estimation and Quality Assessment of Gaussian Noise Corrupted Images

    Science.gov (United States)

    Kamble, V. M.; Bhurchandi, K.

    2018-03-01

    Evaluating the exact quantity of noise present in an image and quality of an image in the absence of reference image is a challenging task. We propose a near perfect noise estimation method and a no reference image quality assessment method for images corrupted by Gaussian noise. The proposed methods obtain initial estimate of noise standard deviation present in an image using the median of wavelet transform coefficients and then obtains a near to exact estimate using curve fitting. The proposed noise estimation method provides the estimate of noise within average error of +/-4%. For quality assessment, this noise estimate is mapped to fit the Differential Mean Opinion Score (DMOS) using a nonlinear function. The proposed methods require minimum training and yields the noise estimate and image quality score. Images from Laboratory for image and Video Processing (LIVE) database and Computational Perception and Image Quality (CSIQ) database are used for validation of the proposed quality assessment method. Experimental results show that the performance of proposed quality assessment method is at par with the existing no reference image quality assessment metric for Gaussian noise corrupted images.

  6. Higher Education in Non-Standard Wage Contracts

    Science.gov (United States)

    Rosti, Luisa; Chelli, Francesco

    2012-01-01

    Purpose: The purpose of this paper is to verify whether higher education increases the likelihood of young Italian workers moving from non-standard to standard wage contracts. Design/methodology/approach: The authors exploit a data set on labour market flows, produced by the Italian National Statistical Office, by interviewing about 85,000…

  7. Parametrisation D'effets Non-Standard EN Phenomenologie Electrofaible

    Science.gov (United States)

    Maksymyk, Ivan

    Cette these pat articles porte sur la parametrisation d'effets non standard en physique electrofaible. Dans chaque analyse, nous avons ajoute plusieurs operateurs non standard au lagrangien du modele standard electrofaible. Les operateurs non standard decrivent les nouveaux effets decoulant d'un modele sous-jacent non-specefie. D'emblee, le nombre d'operateurs non standard que l'on peut inclure dans une telle analyse est illimite. Mais pour une classe specifique de modeles sous-jacents, les effets non standard peuvent etre decrits par un nombre raisonnable d'operateurs. Dans chaque analyse nous avons developpe des expressions pour des observables electrofaibles, en fonction des coefficients des operateurs nouveaux. En effectuant un "fit" statistique sur un ensemble de donnees experimentales precises, nous avons obtenu des contraintes phenomenologiques sur ces coefficients. Dans "Model-Independent Global Constraints on New Physics", nous avons adopte des hypotheses tres peu contraignantes relatives aux modeles sous-jacents. Nous avons tronque le lagrangien effectif a la dimension cinq (inclusivement). Visant la plus grande generalite possible, nous avons admis des interactions qui ne respectent pas les symetries discretes (soit C, P et CP) ainsi que des interactions qui ne conservent pas la saveur. Le lagrangien effectif contient une quarantaine d'operateurs nouveaux. Nous avons determine que, pour la plupart des coefficients des nouveaux operateurs, les contraintes sont assez serrees (2 ou 3%), mais il y a des exceptions interessantes. Dans "Bounding Anomalous Three-Gauge-Boson Couplings", nous avons determine des contraintes phenomenologiques sur les deviations des couplages a trois bosons de jauge par rapport aux interactions prescrites par le modele standard. Pour ce faire, nous avons calcule les contributions indirectes des CTBJ non standard aux observables de basse energie. Puisque le lagrangien effectif est non-renormalisable, certaines difficultes techniques

  8. DOE technical standards list: Directory of DOE and contractor personnel involved in non-government standards activities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    The body of this document contains a listing of DOE employees and DOE contractors who have submitted form DOE F 1300.2, Record of Non-Government Standards Activity, which is attached to the end of this document and to DOE Order 1300.2A. Additional names were added from rosters supplied by non-Government standards bodies. The committees or governing bodies in which the person participates is listed after each name. An asterisk preceding the committee notation indicates that the person has identified himself or herself as the DOE representative on that committee. Appendices to this document are also provided to sort the information by the parent employment organization, by non-Government standards activity, and by the proper names of the non-Government standards organizations and committees. DOE employees and contractors listed in this TSL are those recorded as of July 1, 1996.

  9. Barriers and facilitators to using NHS Direct: a qualitative study of 'users' and 'non-users'.

    Science.gov (United States)

    Cook, Erica J; Randhawa, Gurch; Large, Shirley; Guppy, Andy; Chater, Angel M; Ali, Nasreen

    2014-10-25

    NHS Direct, introduced in 1998, has provided 24/7 telephone-based healthcare advice and information to the public in England and Wales. National studies have suggested variation in the uptake of this service amongst the UK's diverse population. This study provides the first exploration of the barriers and facilitators that impact upon the uptake of this service from the perspectives of both 'users' and 'non- users'. Focus groups were held with NHS Direct 'users' (N = 2) from Bedfordshire alongside 'non-users' from Manchester (N = 3) and Mendip, Somerset (N = 4). Each focus group had between five to eight participants. A total of eighty one people aged between 21 and 94 years old (M: 58.90, SD: 22.70) took part in this research. Each focus group discussion lasted approximately 90 minutes and was audiotape-recorded with participants' permission. The recordings were transcribed verbatim. A framework approach was used to analyse the transcripts. The findings from this research uncovered a range of barriers and facilitators that impact upon the uptake of NHS Direct. 'Non-users' were unaware of the range of services that NHS Direct provided. Furthermore, 'non-users' highlighted a preference for face-to face communication, identifying a lack of confidence in discussing healthcare over the telephone. This was particularly evident among older people with cognitive difficulties. The cost to telephone a '0845' number from a mobile was also viewed to be a barrier to access NHS Direct, expressed more often by 'non-users' from deprived communities. NHS Direct 'users' identified that awareness, ease of use and convenience were facilitators which influenced their decision to use the service. An understanding of the barriers and facilitators which impact on the access and uptake of telephone-based healthcare is essential to move patients towards the self-care model. This research has highlighted the need for telephone-based healthcare services to increase public awareness; through

  10. Integrating ground-penetrating radar and borehole data from a Wadden Sea barrier island

    DEFF Research Database (Denmark)

    Nielsen, Lars; Møller, I.; Nielsen, L. H.

    2009-01-01

    Sea level rise may have large implications for low-gradient barrier coastal systems. This problem motivated an integrated ground-penetrating radar (GPR) and sedimentological study of the Rømø Wadden Sea barrier island. Crossing W-E and N-S-oriented 100 MHz GPR reflection profiles with a total...... island. We document different standard processing steps which lead to increased signal-to-noise ratio, improved resolution and trustworthy GPR-to-borehole correlation. The GPR signals image the subsurface layering with a vertical resolution of ~ 0.2-0.3 m. The penetration depth of the GPR reflection...... conversion of the reflection profiles. The GPR reflections are correlated with sedimentological facies logs, and we test to which extent it is possible to map the architecture of different sedimentary units of the Rømø barrier island based on joint interpretation of the GPR and core data. Detailed...

  11. Barriers to Exercise in Younger and Older Non-Exercising Adult Women: A Cross Sectional Study in London, United Kingdom

    OpenAIRE

    Ansari, Walid El; Lovell, Geoff

    2009-01-01

    A survey of 100 women in the south of London, United Kingdom (UK) compared exercise barrier intensities between non-exercising younger (20-27 years) and older (28-35 years) adult women; and examined childcare duties as perceived barriers to exercise. Perceived barriers to exercise were examined using an Exercise Benefits/Barriers Scale (EBBS) comprising four subscales (exercise milieu; time expenditure; physical exertion; family discouragement). Participants’ number of children was also noted...

  12. Effect of personal and situational variables on noise annoyance: With special reference to implications for en route noise

    Science.gov (United States)

    Fields, James M.

    1992-08-01

    Over 680 publications from 282 social surveys of residents' reactions to environmental noise have been examined to locate 495 published findings on 26 topics concerning non-noise explanations for residents' reactions to environmental noise. This report (1) tabulates the evidence on the 26 response topics, (2) identifies the 495 findings, and (3) discusses the implications for en route noise assessment. After controlling for noise level, over half of the social survey evidence indicates that noise annoyance is not strongly affected by any of the nine demographic variables examined (age, sex, social status, income, education, homeownership, type of dwelling, length of residence, or receipt of benefits from the noise source), but is positively associated with each of the five attitudinal variables examined (a fear of danger from the noise source, a sensitivity towards noise generally, the belief that the authorities can control the noise, the awareness of non-noise impacts of the source, and the belief that the noise source is not important).

  13. An observational study of emergency department utilization among enrollees of Minnesota Health Care Programs: financial and non-financial barriers have different associations.

    Science.gov (United States)

    Shippee, Nathan D; Shippee, Tetyana P; Hess, Erik P; Beebe, Timothy J

    2014-02-08

    Emergency department (ED) use is costly, and especially frequent among publicly insured populations in the US, who also disproportionately encounter financial (cost/coverage-related) and non-financial/practical barriers to care. The present study examines the distinct associations financial and non-financial barriers to care have with patterns of ED use among a publicly insured population. This observational study uses linked administrative-survey data for enrollees of Minnesota Health Care Programs to examine patterns in ED use-specifically, enrollee self-report of the ED as usual source of care, and past-year count of 0, 1, or 2+ ED visits from administrative data. Main independent variables included a count of seven enrollee-reported financial concerns about healthcare costs and coverage, and a count of seven enrollee-reported non-financial, practical barriers to access (e.g., limited office hours, problems with childcare). Covariates included health, health care, and demographic measures. In multivariate regression models, only financial concerns were positively associated with reporting ED as usual source of care, but only non-financial barriers were significantly associated with greater ED visits. Regression-adjusted values indicated notable differences in ED visits by number of non-financial barriers: zero non-financial barriers meant an adjusted 78% chance of having zero ED visits (95% C.I.: 70.5%-85.5%), 15.9% chance of 1(95% C.I.: 10.4%-21.3%), and 6.2% chance (95% C.I.: 3.5%-8.8%) of 2+ visits, whereas having all seven non-financial barriers meant a 48.2% adjusted chance of zero visits (95% C.I.: 30.9%-65.6%), 31.8% chance of 1 visit (95% C.I.: 24.2%-39.5%), and 20% chance (95% C.I.: 8.4%-31.6%) of 2+ visits. Financial barriers were associated with identifying the ED as one's usual source of care but non-financial barriers were associated with actual ED visits. Outreach/literacy efforts may help reduce reliance on/perception of ED as usual source of care

  14. The minimal non-minimal standard model

    International Nuclear Information System (INIS)

    Bij, J.J. van der

    2006-01-01

    In this Letter I discuss a class of extensions of the standard model that have a minimal number of possible parameters, but can in principle explain dark matter and inflation. It is pointed out that the so-called new minimal standard model contains a large number of parameters that can be put to zero, without affecting the renormalizability of the model. With the extra restrictions one might call it the minimal (new) non-minimal standard model (MNMSM). A few hidden discrete variables are present. It is argued that the inflaton should be higher-dimensional. Experimental consequences for the LHC and the ILC are discussed

  15. Dynamics of a Landau–Zener non-dissipative system with fluctuating energy levels

    Energy Technology Data Exchange (ETDEWEB)

    Fai, L.C. [Mesoscopic and Multilayer Structures Laboratory, Department of Physics, Faculty of Science, University of Dschang, Dschang (Cameroon); Diffo, J.T., E-mail: diffojaures@yahoo.com [Mesoscopic and Multilayer Structures Laboratory, Department of Physics, Faculty of Science, University of Dschang, Dschang (Cameroon); Department of Physics, Higher Teachers’ Training College, The University of Maroua, Maroua (Cameroon); Ateuafack, M.E.; Tchoffo, M.; Fouokeng, G.C. [Mesoscopic and Multilayer Structures Laboratory, Department of Physics, Faculty of Science, University of Dschang, Dschang (Cameroon)

    2014-12-01

    This paper considers a Landau–Zener (two-level) system influenced by a three-dimensional Gaussian and non-Gaussian coloured noise and finds a general form of the time dependent diabatic quantum bit (qubit) flip transition probabilities in the fast, intermediate and slow noise limits. The qubit flip probability is observed to mimic (for low-frequencies noise) that of the standard LZ problem. The qubit flip probability is also observed to be the measure of quantum coherence of states. The transition probability is observed to be tailored by non-Gaussian low-frequency noise and otherwise by Gaussian low-frequency coloured noise. Intermediate and fast noise limits are observed to alter the memory of the system in time and found to improve and control quantum information processing.

  16. Dynamics of a Landau–Zener non-dissipative system with fluctuating energy levels

    International Nuclear Information System (INIS)

    Fai, L.C.; Diffo, J.T.; Ateuafack, M.E.; Tchoffo, M.; Fouokeng, G.C.

    2014-01-01

    This paper considers a Landau–Zener (two-level) system influenced by a three-dimensional Gaussian and non-Gaussian coloured noise and finds a general form of the time dependent diabatic quantum bit (qubit) flip transition probabilities in the fast, intermediate and slow noise limits. The qubit flip probability is observed to mimic (for low-frequencies noise) that of the standard LZ problem. The qubit flip probability is also observed to be the measure of quantum coherence of states. The transition probability is observed to be tailored by non-Gaussian low-frequency noise and otherwise by Gaussian low-frequency coloured noise. Intermediate and fast noise limits are observed to alter the memory of the system in time and found to improve and control quantum information processing

  17. Non-auditory effects of noise in industry. IV. A field study on industrial noise and blood pressure

    NARCIS (Netherlands)

    Verbeek, J. H.; van Dijk, F. J.; de Vries, F. F.

    1987-01-01

    Audiometry and casual blood pressure measurements were carried out among industrial workers exposed to noise levels exceeding 80 dB(A). Workers with long-term noise exposure had increased blood pressure, after correction for age. Only a weak correlation was observed between noise-induced hearing

  18. Collaborative noise data collected from smartphones

    Directory of Open Access Journals (Sweden)

    Erwan Bocher

    2017-10-01

    The noise data that are acquired by volunteers around the world (citizen observations, are organized in three files, containing the path of measures (a set of points, standardized noise indicators, noise description and other useful variables (GPS accuracy, speed…. These data can be very relevant later to propose an environmental noise evaluation, through simple or complex treatments.

  19. Acceptable noise level

    DEFF Research Database (Denmark)

    Olsen, Steen Østergaard; Nielsen, Lars Holme; Lantz, Johannes

    2012-01-01

    The acceptable noise level (ANL) is used to quantify the amount of background noise that subjects can accept while listening to speech, and is suggested for prediction of individual hearing-aid use. The aim of this study was to assess the repeatability of the ANL measured in normal-hearing subjects...... using running Danish and non-semantic speech materials as stimuli and modulated speech-spectrum and multi-talker babble noises as competing stimuli....

  20. Acceptable noise level

    DEFF Research Database (Denmark)

    Olsen, Steen Østergaard; Nielsen, Lars Holme; Lantz, Johannes

    2012-01-01

    The acceptable noise level (ANL) is used to quantify the amount of background noise that subjects can accept while listening to speech, and is suggested for prediction of individual hearing-aid use. The aim of this study was to assess the repeatability of the ANL measured in normal-hearing subjec...... using running Danish and non-semantic speech materials as stimuli and modulated speech-spectrum and multi-talker babble noises as competing stimuli....

  1. Adaptive non-local means on local principle neighborhood for noise/artifacts reduction in low-dose CT images.

    Science.gov (United States)

    Zhang, Yuanke; Lu, Hongbing; Rong, Junyan; Meng, Jing; Shang, Junliang; Ren, Pinghong; Zhang, Junying

    2017-09-01

    Low-dose CT (LDCT) technique can reduce the x-ray radiation exposure to patients at the cost of degraded images with severe noise and artifacts. Non-local means (NLM) filtering has shown its potential in improving LDCT image quality. However, currently most NLM-based approaches employ a weighted average operation directly on all neighbor pixels with a fixed filtering parameter throughout the NLM filtering process, ignoring the non-stationary noise nature of LDCT images. In this paper, an adaptive NLM filtering scheme on local principle neighborhoods (PC-NLM) is proposed for structure-preserving noise/artifacts reduction in LDCT images. Instead of using neighboring patches directly, in the PC-NLM scheme, the principle component analysis (PCA) is first applied on local neighboring patches of the target patch to decompose the local patches into uncorrelated principle components (PCs), then a NLM filtering is used to regularize each PC of the target patch and finally the regularized components is transformed to get the target patch in image domain. Especially, in the NLM scheme, the filtering parameter is estimated adaptively from local noise level of the neighborhood as well as the signal-to-noise ratio (SNR) of the corresponding PC, which guarantees a "weaker" NLM filtering on PCs with higher SNR and a "stronger" filtering on PCs with lower SNR. The PC-NLM procedure is iteratively performed several times for better removal of the noise and artifacts, and an adaptive iteration strategy is developed to reduce the computational load by determining whether a patch should be processed or not in next round of the PC-NLM filtering. The effectiveness of the presented PC-NLM algorithm is validated by experimental phantom studies and clinical studies. The results show that it can achieve promising gain over some state-of-the-art methods in terms of artifact suppression and structure preservation. With the use of PCA on local neighborhoods to extract principal structural

  2. Measuring Variability in the Presence of Noise

    Science.gov (United States)

    Welsh, W. F.

    Quantitative measurements of a variable signal in the presence of noise requires very careful attention to subtle affects which can easily bias the measurements. This is not limited to the low-count rate regime, nor is the bias error necessarily small. In this talk I will mention some of the dangers in applying standard techniques which are appropriate for high signal to noise data but fail in the cases where the S/N is low. I will discuss methods for correcting the bias in the these cases, both for periodic and non-periodic variability, and will introduce the concept of the ``filtered de-biased RMS''. I will also illustrate some common abuses of power spectrum interpretation. All of these points will be illustrated with examples from recent work on CV and AGN variability.

  3. Phenomenon of entropic stochastic resonance with asymmetric dichotomous noise and white noise

    International Nuclear Information System (INIS)

    Guo, Feng; Li, Shao-Fu; Cheng, Xiao-Feng

    2012-01-01

    The entropic stochastic resonance (ESR) in a confined system subject to asymmetric dichotomous noise, white noise, and a periodic square-wave signal is investigated. Under the adiabatic approximation condition, by use of the properties of the dichotomous noise, we obtain the expression of the output signal-to-noise ratio (SNR) based on two-state theory. The SNR is shown to be a nonmonotonic function of the strength and asymmetry of the dichotomous noise, the intensity of the white noise, and the amplitude of the square-wave signal. The SNR varies non-monotonically with increases in the parameters of the confined structure. The influence of the correlation rate of the dichotomous noise and the frequency of the external constant force on the SNR is also discussed.

  4. 14 CFR 36.801 - Noise measurement.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Noise measurement. 36.801 Section 36.801 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT NOISE STANDARDS: AIRCRAFT TYPE AND AIRWORTHINESS CERTIFICATION Helicopters § 36.801 Noise measurement. For primary, normal...

  5. Testing non-standard CP violation in neutrino propagation

    International Nuclear Information System (INIS)

    Winter, Walter

    2009-01-01

    Non-standard physics which can be described by effective four fermion interactions may be an additional source of CP violation in the neutrino propagation. We discuss the detectability of such a CP violation at a neutrino factory. We assume the current baseline setup of the international design study of a neutrino factory (IDS-NF) for the simulation. We find that the CP violation from certain non-standard interactions is, in principle, detectable significantly below their current bounds - even if there is no CP violation in the standard oscillation framework. Therefore, a new physics effect might be mis-interpreted as the canonical Dirac CP violation, and a possibly even more exciting effect might be missed

  6. Personal noise dosimeters: Accuracy and reliability in varied settings

    Directory of Open Access Journals (Sweden)

    Sheri Lynn Cook-Cunningham

    2014-01-01

    Full Text Available This study investigated the accuracy, reliability, and characteristics of three brands of personal noise dosimeters (N = 7 units in both pink noise (PN environments and natural environments (NEs through the acquisition of decibel readings, Leq readings and noise doses. Acquisition periods included repeated PN conditions, choir room rehearsals and participant (N = 3 Leq and noise dosages procured during a day in the life of a music student. Among primary results: (a All dosimeters exhibited very strong positive correlations for PN measurements across all instruments; (b all dosimeters were within the recommended American National Standard Institute (ANSI SI.25-1991 standard of ±2 dB (A of a reference measurement; and (c all dosimeters were within the recommended ANSI SI.25-1991 standard of ±2 dB (A when compared with each other. Results were discussed in terms of using personal noise dosimeters within hearing conservation and research contexts and recommendations for future research. Personal noise dosimeters were studied within the contexts of PN environments and NEs (choral classroom and the day in the life of collegiate music students. This quantitative study was a non-experimental correlation design. Three brands of personal noise dosimeters (Cirrus doseBadge, Quest Edge Eg5 and Etymotic ER200D were tested in two environments, a PN setting and a natural setting. There were two conditions within each environment. In the PN environment condition one, each dosimeter was tested individually in comparison with two reference measuring devices (Ivie and Easera while PN was generated by a Whites Instrument PN Tube. In condition two, the PN procedures were replicated for longer periods while all dosimeters measured the sound levels simultaneously. In the NE condition one, all dosimeters were placed side by side on a music stand and recorded sound levels of choir rehearsals over a 7-h rehearsal period. In NE, condition two noise levels were measured

  7. Noise impact assessment of wind farms

    International Nuclear Information System (INIS)

    Hayes, M.

    1993-01-01

    The noise impact assessment of a wind farm is dependent upon a number of factors pertinent to the site. The most controversial is the selection of a criterion which is acceptable to both the developer of a site, in terms of maximising the number of turbines he may operate without fear of injunction to stop, and the local residents and Environmental Health Officer who will have to enforce any agreements. A number of British Standards exist which cover noise issues. There are, however, certain reservations about their use when applied to potential wind farm developments; some of the more relevant standards are outlined. In addition, Draft Planning Guidance notes which have recently been issued are discussed. These are intended to provide an indication to local planning authorities as to what noise levels and criteria may be acceptable when considering noise emitted by wind farms. No European standard for noise emission from wind farms exists but the legislative position in Denmark, the Netherlands, Germany and Sweden is briefly considered. It is considered that when a maximum level criterion is set it should take into account the existing background noise levels based on measurements which are taken at the most sensitive dwellings to the site. A method for calculating emitted noise levels from turbine arrays is described. (UK)

  8. Non-linear degradation model of cement barriers in a borehole repository for disused radioactive sources

    International Nuclear Information System (INIS)

    Gharbieh, Heidar K.; Cota, Stela

    2015-01-01

    Narrow diameter borehole facilities (a few tens of centimeters), like the BOSS concept developed by the IAEA, provide a safe and cost effective disposal option for radioactive waste and particularly disused sources. The BOSS concept (borehole disposal of sealed radioactive sources) comprises a multi-barrier system of cement grout and stainless steel components. In order to predict the long-time performance of the cement barriers as an input of a future safety assessment under the specific hydrochemical and hydrological conditions, a non-linear degradation model was developed in this work. With the assistance of the program 'PHREEQC' it describes the change of the porosity and the hydraulic conductivity with time, which also let to conclusions concerning the change of the sorption capacity of the cement grout. This work includes the theoretical approach and illustrates the non-liner degradation by means of an exemplary water composition found in the saturated zone and the dimensions of the backfill made of cement grout representing a barrier of the BOSS borehole facility. (author)

  9. Tibiofemoral wear in standard and non-standard squat: implication for total knee arthroplasty.

    Science.gov (United States)

    Fekete, Gusztáv; Sun, Dong; Gu, Yaodong; Neis, Patric Daniel; Ferreira, Ney Francisco; Innocenti, Bernardo; Csizmadia, Béla M

    2017-01-01

    Due to the more resilient biomaterials, problems related to wear in total knee replacements (TKRs) have decreased but not disappeared. In the design-related factors, wear is still the second most important mechanical factor that limits the lifetime of TKRs and it is also highly influenced by the local kinematics of the knee. During wear experiments, constant load and slide-roll ratio is frequently applied in tribo-tests beside other important parameters. Nevertheless, numerous studies demonstrated that constant slide-roll ratio is not accurate approach if TKR wear is modelled, while instead of a constant load, a flexion-angle dependent tibiofemoral force should be involved into the wear model to obtain realistic results. A new analytical wear model, based upon Archard's law, is introduced, which can determine the effect of the tibiofemoral force and the varying slide-roll on wear between the tibiofemoral connection under standard and non-standard squat movement. The calculated total wear with constant slide-roll during standard squat was 5.5 times higher compared to the reference value, while if total wear includes varying slide-roll during standard squat, the calculated wear was approximately 6.25 times higher. With regard to non-standard squat, total wear with constant slide-roll during standard squat was 4.16 times higher than the reference value. If total wear included varying slide-roll, the calculated wear was approximately 4.75 times higher. It was demonstrated that the augmented force parameter solely caused 65% higher wear volume while the slide-roll ratio itself increased wear volume by 15% higher compared to the reference value. These results state that the force component has the major effect on wear propagation while non-standard squat should be proposed for TKR patients as rehabilitation exercise.

  10. Assessment of noise environment during construction of a major bridge and associated approach road.

    Science.gov (United States)

    Roy, T K; Mukhopadhyay, A R; Ghosh, S K; Majumder, G

    2011-10-01

    In this paper a methodology to quantify the noise environment, during a major bridge construction and upgrading approach road connectivity, has been provided. Noise levels were monitored at eleven sites. These eleven sites have been classified into three categories - commercial, residential and silence zones. The study was carried out to measure the ambient noise levels in all the eleven sites falling in the above three categories during both day and night times considering both "working" and "non-working" days. It was found that the mean noise level during night time was more, compared to that during day time for commercial, residential as well as silence zones. The likely causes of more noise during night time have been explored. Appropriate remedial measures have been suggested to reduce the noise levels. In addition, the noise levels in the above three zones have been compared, wherever feasible statistically, with the respective zonal standards. Significance has been found in all the cases. The underlying causes and remedies have been provided.

  11. Highway traffic noise prediction based on GIS

    Science.gov (United States)

    Zhao, Jianghua; Qin, Qiming

    2014-05-01

    Before building a new road, we need to predict the traffic noise generated by vehicles. Traditional traffic noise prediction methods are based on certain locations and they are not only time-consuming, high cost, but also cannot be visualized. Geographical Information System (GIS) can not only solve the problem of manual data processing, but also can get noise values at any point. The paper selected a road segment from Wenxi to Heyang. According to the geographical overview of the study area and the comparison between several models, we combine the JTG B03-2006 model and the HJ2.4-2009 model to predict the traffic noise depending on the circumstances. Finally, we interpolate the noise values at each prediction point and then generate contours of noise. By overlaying the village data on the noise contour layer, we can get the thematic maps. The use of GIS for road traffic noise prediction greatly facilitates the decision-makers because of GIS spatial analysis function and visualization capabilities. We can clearly see the districts where noise are excessive, and thus it becomes convenient to optimize the road line and take noise reduction measures such as installing sound barriers and relocating villages and so on.

  12. Barriers to franchise initiation for general remodelers in U.S. remodeling industry: A non-franchisor perspective

    OpenAIRE

    Murray, B. C.

    2008-01-01

    The following report is an exploratory investigation into the barriers of franchise initiation for general contractors in the US remodeling industry. The applicability of theories used to describe why firms franchise is evaluated using secondary quantitative data. Further exploration is achieved by interviewing non-franchising, general remodelers classified as 'potential franchisors'. Overall, the outcomes suggest that franchisee recruitment is a perceived operational barrier by general remod...

  13. Dynamics of tripartite quantum correlations and decoherence in flux qubit systems under local and non-local static noise

    Science.gov (United States)

    Arthur, Tsamouo Tsokeng; Martin, Tchoffo; Fai, Lukong Cornelius

    2018-06-01

    We investigate the dynamics of entanglement, decoherence and quantum discord in a system of three non-interacting superconducting flux qubits (fqubits) initially prepared in a Greenberger-Horne-Zeilinger (GHZ) state and subject to static noise in different, bipartite and common environments, since it is recognized that different noise configurations generally lead to completely different dynamical behavior of physical systems. The noise is modeled by randomizing the single fqubit transition amplitude. Decoherence and quantum correlations dynamics are strongly affected by the purity of the initial state, type of system-environment interaction and the system-environment coupling strength. Specifically, quantum correlations can persist when the fqubits are commonly coupled to a noise source, and reaches a saturation value respective to the purity of the initial state. As the number of decoherence channels increases (bipartite and different environments), decoherence becomes stronger against quantum correlations that decay faster, exhibiting sudden death and revival phenomena. The residual entanglement can be successfully detected by means of suitable entanglement witness, and we derive a necessary condition for entanglement detection related to the tunable and non-degenerated energy levels of fqubits. In accordance with the current literature, our results further suggest the efficiency of fqubits over ordinary ones, as far as the preservation of quantum correlations needed for quantum processing purposes is concerned.

  14. Digital economy and non-standard work

    Directory of Open Access Journals (Sweden)

    Patrizia Tullini

    2016-12-01

    Full Text Available Public and scientific debate on the digital economy is now widespread in many european countries. Also labour law scholars started to pay more attention to the new economical models and to the impact of digital technologies on productive processes. Economics and labour sciences should now move from a descriptive analysis to a deeper theoretical elaboration.The directions of the theoretical analysis are essentially two: the first one deals with the overbearing diffusion of non-standard forms of work on the web, especially on the digital platforms. This trend undermines the traditional foundation of subordination and affects the dynamics of global labour law market. The second directions deals with the increasing use of artificial intelligence in the industrial environment that presents new legal and social issues, concerning both the replacement of standard work with robotics and the complementarity between human work and «non-human agents» work.

  15. Noise levels of toys for children between the ages of birth and 3 ...

    African Journals Online (AJOL)

    Design. A quantitative, non-experimental, descriptive research design was employed for this study. Subjects. Twenty toys, 5 from each of 4 categories, were chosen from a popular toy store in ... the noise levels of toys on the packaging and adherence to ASTM International standards for toy manufacturers are recommended.

  16. Control system architecture: The standard and non-standard models

    International Nuclear Information System (INIS)

    Thuot, M.E.; Dalesio, L.R.

    1993-01-01

    Control system architecture development has followed the advances in computer technology through mainframes to minicomputers to micros and workstations. This technology advance and increasingly challenging accelerator data acquisition and automation requirements have driven control system architecture development. In summarizing the progress of control system architecture at the last International Conference on Accelerator and Large Experimental Physics Control Systems (ICALEPCS) B. Kuiper asserted that the system architecture issue was resolved and presented a open-quotes standard modelclose quotes. The open-quotes standard modelclose quotes consists of a local area network (Ethernet or FDDI) providing communication between front end microcomputers, connected to the accelerator, and workstations, providing the operator interface and computational support. Although this model represents many present designs, there are exceptions including reflected memory and hierarchical architectures driven by requirements for widely dispersed, large channel count or tightly coupled systems. This paper describes the performance characteristics and features of the open-quotes standard modelclose quotes to determine if the requirements of open-quotes non-standardclose quotes architectures can be met. Several possible extensions to the open-quotes standard modelclose quotes are suggested including software as well as the hardware architectural features

  17. Presentation and verification of a simple mathematical model foridentification of the areas behind noise barrierwith the highest performance

    Directory of Open Access Journals (Sweden)

    M. Monazzam

    2009-07-01

    Full Text Available Background and aims   Traffic noise barriers are the most important measure to control the environmental noise pollution. Diffraction from top edge of noise barriers is the most important path of indirect sound wave moves towards receiver.Therefore, most studies are focused on  improvement of this kind.   Methods   T-shape profile barriers are one of the most successful barrier among many different profiles. In this investigation the theory of destructive effect of diffracted waves from real edge of barrier and the wave diffracted from image of the barrier with phase difference of radians is used. Firstly a simple mathematical representation of the zones behind rigid and absorbent T- shape barriers with the highest insertion loss using the destructive effect of indirect path via barrier  image is introduced and then two different profile reflective and absorption barrier is used for  verification of the introduced model   Results   The results are then compared with the results of a verified two dimensional boundary element method at 1/3 octave band frequencies and in a wide field behind those barriers. Avery good agreement between the results has been achieved. In this method effective height is used for any different profile barriers.   Conclusion   The introduced model is very simple, flexible and fast and could be used for choosing the best location of profile rigid and absorptive barriers to achieve the highest  performance.  

  18. Non-standard employment relations and wages among school-leavers in the Netherlands

    NARCIS (Netherlands)

    de Vries, M.R.; Wolbers, M.H.J.

    2005-01-01

    Non-standard (alternatively, flexible) employment has become common in the Netherlands, and viewed as an important weapon for combating youth unemployment. However, if such jobs are 'bad', non-standard employment becomes a matter of concern. In addition, non-standard employment may hit the least

  19. Improved noise-adding radiometer for microwave receivers

    Science.gov (United States)

    Batelaan, P. D.; Stelzried, C. T.; Goldstein, R. M.

    1973-01-01

    Use of input switch and noise reference standard is avoided by using noise-adding technique. Excess noise from solid state noise-diode is coupled into receiver through directional coupler and square-wave modulated at low rate. High sensitivity receivers for radioastronomy applications are utilized with greater confidence in stability of radiometer.

  20. Status of non-standard neutrino interactions

    International Nuclear Information System (INIS)

    Ohlsson, Tommy

    2013-01-01

    The phenomenon of neutrino oscillations has been established as the leading mechanism behind neutrino flavor transitions, providing solid experimental evidence that neutrinos are massive and lepton flavors are mixed. Here we review sub-leading effects in neutrino flavor transitions known as non-standard neutrino interactions (NSIs), which is currently the most explored description for effects beyond the standard paradigm of neutrino oscillations. In particular, we report on the phenomenology of NSIs and their experimental and phenomenological bounds as well as an outlook for future sensitivity and discovery reach. (review article)

  1. Noise, buildings and people

    Energy Technology Data Exchange (ETDEWEB)

    Croome, D J

    1977-01-01

    This book covers the physics of acoustics necessary to understand the analytical aspects of acoustical design and noise control in buildings. The major part is devoted to the problems of noise and man, and other chapters cover features of noise control in and around buildings. In an introduction, building environmental engineering is dealth with in general terms of architecture, creativity, systms design, etc. Aspects of the acoustical environment, noise sources in buildings, control of airborne and structure-borne noise and acoustical design techniques are covered in Part II. Items include: comfort, physiological response to noise and vibrations, noise criteria, human performance, speech communication, landscaped offices, sound generation by air-conditioning and heating equipment, building structure and noise attenuation, acoustical design. Part III gives some fundamentals of acoustics; mechanical vibration, wave motion, propagation of sound, structure-borne sound, behavior of sound in rooms, transmission of sound through structure. References include lists of British standards and booklets on health and safety at work.

  2. Noise Producing Toys and the Efficacy of Product Standard Criteria to Protect Health and Education Outcomes

    Directory of Open Access Journals (Sweden)

    Stuart J. McLaren

    2013-12-01

    Full Text Available An evaluation of 28 commercially available toys imported into New Zealand revealed that 21% of these toys do not meet the acoustic criteria in the ISO standard, ISO 8124-1:2009 Safety of Toys, adopted by Australia and New Zealand as AS/NZS ISO 8124.1:2010. While overall the 2010 standard provided a greater level of protection than the earlier 2002 standard, there was one high risk toy category where the 2002 standard provided greater protection. A secondary set of toys from the personal collections of children known to display atypical methods of play with toys, such as those with autism spectrum disorders (ASD, was part of the evaluation. Only one of these toys cleanly passed the 2010 standard, with the remainder failing or showing a marginal-pass. As there is no tolerance level stated in the standards to account for interpretation of data and experimental error, a value of +2 dB was used. The findings of the study indicate that the current standard is inadequate in providing protection against excessive noise exposure. Amendments to the criteria have been recommended that apply to the recently adopted 2013 standard. These include the integration of the new approaches published in the recently amended European standard (EN 71 on safety of toys.

  3. Noise producing toys and the efficacy of product standard criteria to protect health and education outcomes.

    Science.gov (United States)

    McLaren, Stuart J; Page, Wyatt H; Parker, Lou; Rushton, Martin

    2013-12-19

    An evaluation of 28 commercially available toys imported into New Zealand revealed that 21% of these toys do not meet the acoustic criteria in the ISO standard, ISO 8124-1:2009 Safety of Toys, adopted by Australia and New Zealand as AS/NZS ISO 8124.1:2010. While overall the 2010 standard provided a greater level of protection than the earlier 2002 standard, there was one high risk toy category where the 2002 standard provided greater protection. A secondary set of toys from the personal collections of children known to display atypical methods of play with toys, such as those with autism spectrum disorders (ASD), was part of the evaluation. Only one of these toys cleanly passed the 2010 standard, with the remainder failing or showing a marginal-pass. As there is no tolerance level stated in the standards to account for interpretation of data and experimental error, a value of +2 dB was used. The findings of the study indicate that the current standard is inadequate in providing protection against excessive noise exposure. Amendments to the criteria have been recommended that apply to the recently adopted 2013 standard. These include the integration of the new approaches published in the recently amended European standard (EN 71) on safety of toys.

  4. Effect of fMRI acoustic noise on non-auditory working memory task: comparison between continuous and pulsed sound emitting EPI.

    Science.gov (United States)

    Haller, Sven; Bartsch, Andreas J; Radue, Ernst W; Klarhöfer, Markus; Seifritz, Erich; Scheffler, Klaus

    2005-11-01

    Conventional blood oxygenation level-dependent (BOLD) based functional magnetic resonance imaging (fMRI) is accompanied by substantial acoustic gradient noise. This noise can influence the performance as well as neuronal activations. Conventional fMRI typically has a pulsed noise component, which is a particularly efficient auditory stimulus. We investigated whether the elimination of this pulsed noise component in a recent modification of continuous-sound fMRI modifies neuronal activations in a cognitively demanding non-auditory working memory task. Sixteen normal subjects performed a letter variant n-back task. Brain activity and psychomotor performance was examined during fMRI with continuous-sound fMRI and conventional fMRI. We found greater BOLD responses in bilateral medial frontal gyrus, left middle frontal gyrus, left middle temporal gyrus, left hippocampus, right superior frontal gyrus, right precuneus and right cingulate gyrus with continuous-sound compared to conventional fMRI. Conversely, BOLD responses were greater in bilateral cingulate gyrus, left middle and superior frontal gyrus and right lingual gyrus with conventional compared to continuous-sound fMRI. There were no differences in psychomotor performance between both scanning protocols. Although behavioral performance was not affected, acoustic gradient noise interferes with neuronal activations in non-auditory cognitive tasks and represents a putative systematic confound.

  5. The influence of acoustical and non-acoustical factors on short-term annoyance due to aircraft noise in the field - The COSMA study.

    Science.gov (United States)

    Bartels, Susanne; Márki, Ferenc; Müller, Uwe

    2015-12-15

    Air traffic has increased for the past decades and is forecasted to continue to grow. Noise due to current airport operations can impair the physical and psychological well-being of airport residents. The field study investigated aircraft noise-induced short-term (i.e., within hourly intervals) annoyance in local residents near a busy airport. We aimed at examining the contribution of acoustical and non-acoustical factors to the annoyance rating. Across four days from getting up till going to bed, 55 residents near Cologne/Bonn Airport (M=46years, SD=14years, 34 female) rated their annoyance due to aircraft noise at hourly intervals. For each participant and each hour, 26 noise metrics from outdoor measurements and further 6 individualized metrics that took into account the sound attenuation due to each person's whereabouts in and around their homes were obtained. Non-acoustical variables were differentiated into situational factors (time of day, performed activity during past hour, day of the week) and personal factors (e.g., sensitivity to noise, attitudes, domestic noise insulation). Generalized Estimation Equations were applied for the development of a prediction model for annoyance. Acoustical factors explained only a small proportion (13.7%) of the variance in the annoyance ratings. The number of fly-overs predicted annoyance better than did equivalent and maximum sound pressure levels. The proportion of explained variance in annoyance rose considerably (to 27.6%) when individualized noise metrics as well as situational and personal variables were included in the prediction model. Consideration of noise metrics related to the number of fly-overs and individual adjustment of noise metrics can improve the prediction of short-term annoyance compared to models using equivalent outdoor levels only. Non-acoustical factors have remarkable impact not only on long-term annoyance as shown before but also on short-term annoyance judged in the home environment. Copyright

  6. Improved GIS-based Methods for Traffic Noise Impact Assessment

    DEFF Research Database (Denmark)

    Nielsen, Otto Anker; Bloch, Karsten Sand

    1996-01-01

    When vector-based GIS-packages are used for traffic noise impact assessments, the buffer-technique is usually employed for the study: 1. For each road segment buffer-zones representing different noise-intervals are generated, 2. The buffers from all road segments are smoothed together, and 3....... The number of buildings within the buffers are enumerated. This technique provides an inaccurate assessment of the noise diffusion since it does not correct for buildings barrier and reflection to noise. The paper presents the results from a research project where the traditional noise buffer technique...... was compared with a new method which includes these corrections. Both methods follow the Common Nordic Noise Calculation Model, although the traditional buffer technique ignores parts of the model. The basis for the work was a digital map of roads and building polygons, combined with a traffic- and road...

  7. Sea-Level Trend Uncertainty With Pacific Climatic Variability and Temporally-Correlated Noise

    Science.gov (United States)

    Royston, Sam; Watson, Christopher S.; Legrésy, Benoît; King, Matt A.; Church, John A.; Bos, Machiel S.

    2018-03-01

    Recent studies have identified climatic drivers of the east-west see-saw of Pacific Ocean satellite altimetry era sea level trends and a number of sea-level trend and acceleration assessments attempt to account for this. We investigate the effect of Pacific climate variability, together with temporally-correlated noise, on linear trend error estimates and determine new time-of-emergence (ToE) estimates across the Indian and Pacific Oceans. Sea-level trend studies often advocate the use of auto-regressive (AR) noise models to adequately assess formal uncertainties, yet sea level often exhibits colored but non-AR(1) noise. Standard error estimates are over- or under-estimated by an AR(1) model for much of the Indo-Pacific sea level. Allowing for PDO and ENSO variability in the trend estimate only reduces standard errors across the tropics and we find noise characteristics are largely unaffected. Of importance for trend and acceleration detection studies, formal error estimates remain on average up to 1.6 times those from an AR(1) model for long-duration tide gauge data. There is an even chance that the observed trend from the satellite altimetry era exceeds the noise in patches of the tropical Pacific and Indian Oceans and the south-west and north-east Pacific gyres. By including climate indices in the trend analysis, the time it takes for the observed linear sea-level trend to emerge from the noise reduces by up to 2 decades.

  8. Effects of noise overexposure on distortion product otoacoustic emissions

    DEFF Research Database (Denmark)

    de Toro, Miguel Angel Aranda

    are assumed to be equally hazardous for our hearing. Nevertheless, the standard allows adding a +5dB penalty to impulsive and tonal noises based on the presumption that they might pose a higher risk of hearing loss. This PhD thesis investigates the effect of different occupational noise exposures......The risk of noise-induced hearing loss (NIHL) at the workplace can be predicted according to the International Standard ISO 1999:1990. The standard is applicable to all types of noise and it is based on measurements of the total acoustic energy (LEX,8ℎ). Therefore, noises with equal energy...... may be more appropriate for tonal exposures. This presentation will also address methodological aspects of DPOAE measurements that might improve hearing diagnosis and detection of hearing loss....

  9. State-of-the-Art Review on Sustainable Design and Construction of Quieter Pavements—Part 1: Traffic Noise Measurement and Abatement Techniques

    Directory of Open Access Journals (Sweden)

    MD Ohiduzzaman

    2016-08-01

    Full Text Available Noise pollution due to highway traffic has drawn the attention of transportation agencies worldwide. Noise pollution is an irritant to residents, especially in urban areas near roads with high traffic volume. In addition to its adverse effects on the quality of life, traffic noise can induce stress that could lead to sleep disturbance and anxiety. Traditionally, noise barrier walls have been used for highways to mitigate traffic noise. However, using barrier walls as a noise abatement measure has proven to be very expensive. In addition to the cost, noise barrier walls are not always effective because they must break the line of sight to work properly, which is not always possible in case of intersections or driveways. Therefore, researchers especially from Europe and USA have been very proactive to reduce the noise at source. A number of research studies show traffic noise can be reduced by using an alternative surface type or changing texture of the pavement while complying with other requirements of sustainability, i.e., safety, structural durability, construction and maintenance costs. This paper presents a comprehensive review of the research conducted on this subject. A review of the tire-pavement noise generation and amplification mechanism, various traffic noise measurement methods and correlation among these methods, in addition to the abatement techniques used by various agencies to reduce pavement noise, is also presented.

  10. Noise exposure in occupational setting associated with elevated blood pressure in China

    Directory of Open Access Journals (Sweden)

    Shuchang Chen

    2017-01-01

    Full Text Available Abstract Background Hypertension is the primary out-auditory adverse outcome caused due to occupational noise exposure. This study investigated the associations of noise exposure in an occupational setting with blood pressure and risk of hypertension. Methods A total of 1,390 occupational noise-exposed workers and 1399 frequency matched non-noise-exposed subjects were recruited from a cross-sectional survey of occupational noise-exposed and the general population, respectively. Blood pressure was measured using a mercury sphygmomanometer following a standard protocol. Multiple logistic regression was used to calculate the odds ratio (OR and 95% confidence interval (CI of noise exposure adjusted by potential confounders. Results Noise-exposed subjects had significantly higher levels of systolic blood pressure(SBP (125.1 ± 13.9 mm Hg and diastolic blood pressure (DBP (77.6 ± 10.7 mm Hg than control subjects (SBP: 117.2 ± 15.7 mm Hg, DBP: 70.0 ± 10.5 mm Hg (P  0.05. Conclusions Occupational noise exposure was associated with higher levels of SBP, DBP, and the risk of hypertension. These findings indicate that effective and feasible measures should be implemented to reduce the risk of hypertension caused by occupational noise exposure.

  11. Effect of cigarette smoking on noise-induced hearing loss in workers exposed to occupational noise in China.

    Science.gov (United States)

    Tao, Liyuan; Davis, Robert; Heyer, Nicholas; Yang, Qiuling; Qiu, Wei; Zhu, Liangliang; Li, Nan; Zhang, Hua; Zeng, Lin; Zhao, Yiming

    2013-01-01

    Excessive exposure to high noise level environments has the potential to cause noise-induced hearing loss (NIHL), and cigarette smoking has also been shown to have a potential adverse effect on hearing. The aim of this study was to determine whether smoking interacts with noise in the development of hearing loss, and if so, the extent of the contribution from smoking on NIHL. A cross-sectional study was designed to assess the effect of smoking on NIHL in 517 male workers (non-smokers: N = 199; smokers: N = 318) exposed to a high-level industrial noise environment in China. Shift-long temporal waveforms of the noise that workers were exposed to for evaluation of noise exposures, and audiometric threshold measures were obtained on all selected subjects. The subjects used hearing protection devices only within the last 1-2 years. The results suggest that smoking has an adverse effect on NIHL in workers exposed to high level industrial noise, i.e., the median high frequency hearing thresholds were significantly greater in smokers than non-smokers exposed to noise for more than 10 years. This effect was observed at 4.0 and 6.0 kHz. Smoking did not have an adverse effect on NIHL in workers exposed to noise less than 10 years. Multivariate regression analysis revealed that the odds ratio (OR) for high frequency hearing loss (i.e., hearing threshold greater than 40 dB at 4.0 kHz) were 1.94 for smokers in comparison to non-smokers. The results suggest that: (1) smokers have a higher risk of developing high frequency hearing loss than non-smokers with a similar occupational noise exposure, and (2) the interaction between cigarette smoking and high-level noise exposure may be additive. There is a need to develop and analyze a larger database of workers with well-documented exposures and smoking histories for better understanding of the effect of smoking on NIHL incurred from high-level industrial noise exposures. A better understanding of the role of smoking may lead to its

  12. Non-linear dynamical classification of short time series of the rössler system in high noise regimes.

    Science.gov (United States)

    Lainscsek, Claudia; Weyhenmeyer, Jonathan; Hernandez, Manuel E; Poizner, Howard; Sejnowski, Terrence J

    2013-01-01

    Time series analysis with delay differential equations (DDEs) reveals non-linear properties of the underlying dynamical system and can serve as a non-linear time-domain classification tool. Here global DDE models were used to analyze short segments of simulated time series from a known dynamical system, the Rössler system, in high noise regimes. In a companion paper, we apply the DDE model developed here to classify short segments of encephalographic (EEG) data recorded from patients with Parkinson's disease and healthy subjects. Nine simulated subjects in each of two distinct classes were generated by varying the bifurcation parameter b and keeping the other two parameters (a and c) of the Rössler system fixed. All choices of b were in the chaotic parameter range. We diluted the simulated data using white noise ranging from 10 to -30 dB signal-to-noise ratios (SNR). Structure selection was supervised by selecting the number of terms, delays, and order of non-linearity of the model DDE model that best linearly separated the two classes of data. The distances d from the linear dividing hyperplane was then used to assess the classification performance by computing the area A' under the ROC curve. The selected model was tested on untrained data using repeated random sub-sampling validation. DDEs were able to accurately distinguish the two dynamical conditions, and moreover, to quantify the changes in the dynamics. There was a significant correlation between the dynamical bifurcation parameter b of the simulated data and the classification parameter d from our analysis. This correlation still held for new simulated subjects with new dynamical parameters selected from each of the two dynamical regimes. Furthermore, the correlation was robust to added noise, being significant even when the noise was greater than the signal. We conclude that DDE models may be used as a generalizable and reliable classification tool for even small segments of noisy data.

  13. Landing gear noise attenuation

    Science.gov (United States)

    Moe, Jeffrey W. (Inventor); Whitmire, Julia (Inventor); Kwan, Hwa-Wan (Inventor); Abeysinghe, Amal (Inventor)

    2011-01-01

    A landing gear noise attenuator mitigates noise generated by airframe deployable landing gear. The noise attenuator can have a first position when the landing gear is in its deployed or down position, and a second position when the landing gear is in its up or stowed position. The noise attenuator may be an inflatable fairing that does not compromise limited space constraints associated with landing gear retraction and stowage. A truck fairing mounted under a truck beam can have a compliant edge to allow for non-destructive impingement of a deflected fire during certain conditions.

  14. On the Performance Analysis of Digital Communication Systems Perturbed by Non-Gaussian Noise and Interference

    KAUST Repository

    Soury, Hamza

    2016-06-29

    The Gaussian distribution is typically used to model the additive noise affecting communication systems. However, in many cases the noise cannot be modeled by a Gaussian distribution. In this thesis, we investigate the performance of different communication systems perturbed by non-Gaussian noise. Three families of noise are considered in this work, namely the generalized Gaussian noise, the Laplace noise/interference, and the impulsive noise that is modeled by an α-stable distribution. More specifically, in the first part of this thesis, the impact of an additive generalized Gaussian noise is studied by computing the average symbol error rate (SER) of one dimensional and two dimensional constellations in fading environment. We begin by the simple case of two symbols, i.e. binary phase shift keying (BPSK) constellation. From the results of this constellation, we extended the work to the average SER of an M pulse amplitude modulation (PAM). The first 2 − D constellation is the M quadrature amplitude modulation (QAM) (studied for two geometric shapes, namely square and rectangular), which is the combination of two orthogonal PAM signals (in-phase and quadrature phase PAM). In the second part, the system performance of a circular constellation, namely M phase shift keying (MPSK) is studied in conjunction with a Laplace noise with independent noise components. A closed form and an asymptotic expansion of the SER are derived for two detectors, maximum likelihood and minimum distance detectors. Next, we look at the intra cell interference of a full duplex cellular network which is shown to follow a Laplacian distribution with dependent, but uncorrelated, complex components. The densities of that interference are expressed in a closed form in order to obtain the SER of several communication systems (BPSK, PAM, QAM, and MPSK). Finally, we study the statistics of the α-stable distribution. Those statistics are expressed in closed form in terms of the Fox H function and

  15. Cladding failure model III (CFM III). A simple model for iodine induced stress corrosion cracking of zirconium-lined barrier and standard zircaloy cladding

    International Nuclear Information System (INIS)

    Tasooji, A.; Miller, A.K.

    1984-01-01

    A previously developed unified model (SCCIG*) for predicting iodine induced SCC in standard Zircaloy cladding was modified recently into the ''SCCIG-B'' model which predicts the stress corrosion cracking behaviour of zirconium lined barrier cladding. Several published papers have presented the capability of these models for predicting various observed behaviours related to SCC. A closed form equation, called Cladding Failure Model III (CMFIII), has been derived from the SCCIG-B model. CFMIII takes the form of an explicit equation for the radial crack growth rate dc/dt as a function of hoop strain, crack depth, temperature, and surface iodine concentration in irradiated cladding (both barrier and standard Zircaloy). CMFIII has approximately the same predictive capabilities as the physically based SCCIG and/or SCCIG-B models but is computationally faster and more convenient and can be easily utilized in fuel performance codes for predicting the behaviour of barrier and standard claddings in reactor operations. (author)

  16. The need to revitalize our national noise policy

    Science.gov (United States)

    Lang, William W.; Beranek, Leo L.

    2002-05-01

    At the present time, our Nation does not have a national noise policy. The Congress attempted to define one with the passage of the Noise Control Act of 1972 as follows: The Congress declares that it is the policy of the United States to promote an environment for all Americans free from noise that jeopardizes their health and welfare. The Act assigned to the Environmental Protection Agency (EPA) the role of leading Federal agency with the task of coordinating the programs of all Federal agencies relating to noise research and noise control. Ten years later (1982), all funds for noise control were withdrawn from the EPA, and today the Nation is without an effective, overall noise policy. Residual responsibility for the control of environmental and occupational noise currently rests with a dozen agencies of the Federal government, as well as State, municipal, and local authorities. But the activities of these organizations are largely uncoordinated, and the enforcement of existing noise control regulations is at best sporadic, and in some cases nonexistent. To assure our quality of life and to minimize the economic impact of potential trade barriers, a study team is recommending that a national noise policy be developed and then implemented in the immediate future.

  17. Novel Diagonal Reloading Based Direction of Arrival Estimation in Unknown Non-Uniform Noise

    Directory of Open Access Journals (Sweden)

    Hao Zhou

    2018-01-01

    Full Text Available Nested array can expand the degrees of freedom (DOF from difference coarray perspective, but suffering from the performance degradation of direction of arrival (DOA estimation in unknown non-uniform noise. In this paper, a novel diagonal reloading (DR based DOA estimation algorithm is proposed using a recently developed nested MIMO array. The elements in the main diagonal of the sample covariance matrix are eliminated; next the smallest MN-K eigenvalues of the revised matrix are obtained and averaged to estimate the sum value of the signal power. Further the estimated sum value is filled into the main diagonal of the revised matrix for estimating the signal covariance matrix. In this case, the negative effect of noise is eliminated without losing the useful information of the signal matrix. Besides, the degrees of freedom are expanded obviously, resulting in the performance improvement. Several simulations are conducted to demonstrate the effectiveness of the proposed algorithm.

  18. Interaction of smoking and occupational noise exposure on hearing loss: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Mohammadi Saber

    2007-07-01

    Full Text Available Abstract Background Noise is the most common hazardous agent at workplaces. Noise induced hearing loss (NIHL has been known since the industrial revolution. Although NIHL is permanent, irreversible and frequent, it is preventable. The economic costs of NIHL have been estimated to be about billions of dollars. Besides, cigarette smoking is a common habit worldwide, and according to some recent studies smoking and noise may act in common causal pathways for hearing loss. Methods A cross-sectional study was designed to study the effect of smoking on NIHL in 206 male smoker workers and 206 male non-smoker workers in a large food-producing factory, in which workers were exposed to noise levels exceeding 85dBA. To determine noise exposure level, we used sound level measurements reported by industrial hygienists. A qualified audiologist assessed hearing acuity by using standardized audiometric procedures assuring at least 14 h of noise avoidance. Results We observed that the percentage of workers with hearing threshold differences of greater than or equal to 30 dB between 4000 Hz and 1000 Hz in both ears were 49.5% and 11.2% in smoker and non smoker groups, respectively (Odds ratio = 7.8, 95% CI = 4.7 – 13, and the percentage of workers with a hearing threshold of greater than 25dB at 4000 Hz in the better ear were 63.6% and 18.4% in smoker and non smoker groups, respectively. This difference was statistically significant after adjustment for age and exposure duration. Conclusion It can be concluded that smoking can accelerate noise induced hearing loss, but more research is needed to understand the underlying mechanisms. Accurate follow up of smoker workers who are exposed to noise levels exceeding 85 dBA is suggested. Smokers should periodically attend educational courses on "smoking cessation", especially in noisy workplaces.

  19. Interaction of smoking and occupational noise exposure on hearing loss: a cross-sectional study.

    Science.gov (United States)

    Pouryaghoub, Gholamreza; Mehrdad, Ramin; Mohammadi, Saber

    2007-07-03

    Noise is the most common hazardous agent at workplaces. Noise induced hearing loss (NIHL) has been known since the industrial revolution. Although NIHL is permanent, irreversible and frequent, it is preventable. The economic costs of NIHL have been estimated to be about billions of dollars. Besides, cigarette smoking is a common habit worldwide, and according to some recent studies smoking and noise may act in common causal pathways for hearing loss. A cross-sectional study was designed to study the effect of smoking on NIHL in 206 male smoker workers and 206 male non-smoker workers in a large food-producing factory, in which workers were exposed to noise levels exceeding 85 dBA. To determine noise exposure level, we used sound level measurements reported by industrial hygienists.A qualified audiologist assessed hearing acuity by using standardized audiometric procedures assuring at least 14 h of noise avoidance. We observed that the percentage of workers with hearing threshold differences of greater than or equal to 30 dB between 4000 Hz and 1000 Hz in both ears were 49.5% and 11.2% in smoker and non smoker groups, respectively (Odds ratio = 7.8, 95% CI = 4.7-13), and the percentage of workers with a hearing threshold of greater than 25 dB at 4000 Hz in the better ear were 63.6% and 18.4% in smoker and non smoker groups, respectively. This difference was statistically significant after adjustment for age and exposure duration. It can be concluded that smoking can accelerate noise induced hearing loss, but more research is needed to understand the underlying mechanisms. Accurate follow up of smoker workers who are exposed to noise levels exceeding 85 dBA is suggested. Smokers should periodically attend educational courses on "smoking cessation", especially in noisy workplaces.

  20. Fractals in Power Reactor Noise

    International Nuclear Information System (INIS)

    Aguilar Martinez, O.

    1994-01-01

    In this work the non- lineal dynamic problem of power reactor is analyzed using classic concepts of fractal analysis as: attractors, Hausdorff-Besikovics dimension, phase space, etc. A new non-linear problem is also analyzed: the discrimination of chaotic signals from random neutron noise signals and processing for diagnosis purposes. The advantages of a fractal analysis approach in the power reactor noise are commented in details

  1. Noise-immune complex correlation for optical coherence angiography based on standard and Jones matrix optical coherence tomography.

    Science.gov (United States)

    Makita, Shuichi; Kurokawa, Kazuhiro; Hong, Young-Joo; Miura, Masahiro; Yasuno, Yoshiaki

    2016-04-01

    This paper describes a complex correlation mapping algorithm for optical coherence angiography (cmOCA). The proposed algorithm avoids the signal-to-noise ratio dependence and exhibits low noise in vasculature imaging. The complex correlation coefficient of the signals, rather than that of the measured data are estimated, and two-step averaging is introduced. Algorithms of motion artifact removal based on non perfusing tissue detection using correlation are developed. The algorithms are implemented with Jones-matrix OCT. Simultaneous imaging of pigmented tissue and vasculature is also achieved using degree of polarization uniformity imaging with cmOCA. An application of cmOCA to in vivo posterior human eyes is presented to demonstrate that high-contrast images of patients' eyes can be obtained.

  2. Noise-immune complex correlation for optical coherence angiography based on standard and Jones matrix optical coherence tomography

    Science.gov (United States)

    Makita, Shuichi; Kurokawa, Kazuhiro; Hong, Young-Joo; Miura, Masahiro; Yasuno, Yoshiaki

    2016-01-01

    This paper describes a complex correlation mapping algorithm for optical coherence angiography (cmOCA). The proposed algorithm avoids the signal-to-noise ratio dependence and exhibits low noise in vasculature imaging. The complex correlation coefficient of the signals, rather than that of the measured data are estimated, and two-step averaging is introduced. Algorithms of motion artifact removal based on non perfusing tissue detection using correlation are developed. The algorithms are implemented with Jones-matrix OCT. Simultaneous imaging of pigmented tissue and vasculature is also achieved using degree of polarization uniformity imaging with cmOCA. An application of cmOCA to in vivo posterior human eyes is presented to demonstrate that high-contrast images of patients’ eyes can be obtained. PMID:27446673

  3. Analysis of approaches to classification of forms of non-standard employment

    Directory of Open Access Journals (Sweden)

    N. V. Dorokhova

    2017-01-01

    Full Text Available Currently becoming more widespread non-standard forms of employment. If this is not clear approach to the definition and maintenance of non-standard employment. In the article the analysis of diverse interpretations of the concept, on what basis, the author makes a conclusion about the complexity and contradictory nature of precarious employment as an economic category. It examines different approaches to classification of forms of precarious employment. The main forms of precarious employment such as flexible working year, flexible working week, flexible working hours, remote work, employees on call, shift forwarding; Agency employment, self-employment, negotiator, underemployment, over employment, employment on the basis of fixed-term contracts employment based on contract of civil-legal nature, one-time employment, casual employment, temporary employment, secondary employment and part-time. The author’s approach to classification of non-standard forms of employment, based on identifying the impact of atypical employment on the development of human potential. For the purpose of classification of non-standard employment forms from the standpoint of their impact on human development as the criteria of classification proposed in the following: working conditions, wages and social guarantees, possibility of workers ' participation in management, personal development and self-employment stability. Depending on what value each of these criteria, some form of non-standard employment can be attributed to the progressive or regressive. Classification of non-standard forms of employment should be the basis of the state policy of employment management.

  4. Evaluation of Noise pollution in Omidiyeh city, 2015

    Directory of Open Access Journals (Sweden)

    satar soltanian

    2016-03-01

    Full Text Available Introduction and Purpose: Noise pollution is one of the important environmental problems that has been on a growing trend in the recent years. This study was conducted to evaluate the level of noise pollution in Omidiyeh city, Iran. Methods: Testo 815 sound level meter was employed to quantify the sound pressure level (SPL. The measurements were conducted during 7-9 am, 12- 14 am, and 19-21 pm, at three locations (one station in each of commercial, residential, and commercial-residential areas, and the results were compared with the standard level of noise pollution. Results: The results indicated that the SPL at all the specified times and areas were higher than the standard level. The mean SPL in commercial, residential, and commercial-residential areas were 72.86, 67.36, and 61.71 dB, respectively, which were 7.86, 7.36, and 6.71 dB higher than the standards of noise in the open air. Conclusion: This study showed that the SPL was higher than standard level, Therefor new approaches should be implemented to reduce the level of noise pollution

  5. Noise properties of Hilbert transform evaluation

    International Nuclear Information System (INIS)

    Pavliček, Pavel; Svak, Vojtěch

    2015-01-01

    The Hilbert transform is a standard method for the calculation of the envelope and phase of a modulated signal in optical measurement methods. Usually, the intensity of light is converted into an electric signal at a detector. Therefore the actual spatially or temporally sampled signal is always affected by noise. Because the noise values of individual samples are independent, the noise can be considered as white. If the envelope and phase are calculated from the noised signal, they will also be affected by the noise. We calculate the variance and spectral density of both the envelope noise and the phase noise. We determine which parameters influence the variance and spectral density of both the envelope noise and the phase noise. Finally, we determine the influence of the noise on the measurement uncertainty in white-light interferometry and fringe-pattern analysis. (paper)

  6. Current-phase relations and noise in rf biased SQUIDS

    International Nuclear Information System (INIS)

    Jackel, L.D.; Clark, T.D.; Buhrman, R.A.

    1975-01-01

    An investigation was made of the effect of the weak link current-phase relation on noise in rf biased SQUIDs. Non-sinusoidal current-phase relations were observed in various weak links, and these non-sinusoidal relations were correlated with significantly increased intrinsic noise in the SQUID ring. The current-phase relation was also found to affect the amplitude of the rf SQUID ring dissipation. The result of an rf SQUID system noise analysis shows that, due to increased intrinsic noise and reduced ring dissipation, the minimum attainable noise for a SQUID ring having a very non-sinusoidal current-phase relation is considerably greater than for a ring with a sinusoidal relation

  7. 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

  8. WHO Environmental Noise Guidelines for the European Region: A Systematic Review on Environmental Noise and Annoyance

    Directory of Open Access Journals (Sweden)

    Rainer Guski

    2017-12-01

    Full Text Available Background: This paper describes a systematic review and meta-analyses on effects of environmental noise on annoyance. The noise sources include aircraft, road, and rail transportation noise as well as wind turbines and noise source combinations. Objectives: Update knowledge about effects of environmental noise on people living in the vicinity of noise sources. Methods: Eligible were published studies (2000–2014 providing comparable acoustical and social survey data including exposure-response functions between standard indicators of noise exposure and standard annoyance responses. The systematic literature search in 20 data bases resulted in 62 studies, of which 57 were used for quantitative meta-analyses. By means of questionnaires sent to the study authors, additional study data were obtained. Risk of bias was assessed by means of study characteristics for individual studies and by funnel plots to assess the risk of publication bias. Main Results: Tentative exposure-response relations for percent highly annoyed residents (%HA in relation to noise levels for aircraft, road, rail, wind turbine and noise source combinations are presented as well as meta-analyses of correlations between noise levels and annoyance raw scores, and the OR for increase of %HA with increasing noise levels. Quality of evidence was assessed using the GRADE terminology. The evidence of exposure-response relations between noise levels and %HA is moderate (aircraft and railway or low (road traffic and wind turbines. The evidence of correlations between noise levels and annoyance raw scores is high (aircraft and railway or moderate (road traffic and wind turbines. The evidence of ORs representing the %HA increase by a certain noise level increase is moderate (aircraft noise, moderate/high (road and railway traffic, and low (wind turbines. Strengths and Limitations: The strength of the evidence is seen in the large total sample size encompassing the included studies (e

  9. Measured and calculated noise reduction of rail dampers and absorption plates on a high speed slab track

    NARCIS (Netherlands)

    Dittrich, M.G.; Graafland, F.; Eisses, A.R.; Nijhof, M.J.J.

    2015-01-01

    Rail dampers and sound absorbing plates have been tested on a high speed railway slab track in a walled cutting at a noise sensitive location. Their noise reduction has been determined from pass-by measurements during service and predicted using BEM calculations. The cutting depth, noise barrier

  10. Observation of Synchrotron Radiation Using Low Noise Block (LNB) at ANKA

    CERN Document Server

    Judin, V; Hofmann, A; Huttel, E; Kehrer, B; Klein, M; Marsching, S; Muller, A-S; Smale, N; Caspers, F

    2011-01-01

    Generally Coherent Synchrotron Radiation (CSR) is emitted for wavelengths longer than or equal the bunch length, so for CSR in the THz-range short bunches are required. There are two types of detectors in this range of the spectrum: slow detectors like a golay cell or pyrometric detectors (used for e.g. imaging, spectroscopy) and fast detectors like superconducting bolometer detector systems and Schottky Barrier diodes (used for e.g. the investigation of dynamic processes in accelerator physics). The hot electron bolometer (HEB) detector system is a member of second group. It is very fast and has broad spectral characteristics, but unfortunately very expensive and have to be cooled using liquid helium. If the broad spectral response is not important, it will be suitably to use a Schottky Barrier diode instead. These detectors are massively cheaper but also slower. As an alternative to a Schottky diode a LNB (Low Noise Block) can be also used. It is usually used in standard TV-SAT-receivers. Due to mass produc...

  11. Spatial traffic noise pollution assessment – A case study

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Monazzam

    2015-06-01

    Full Text Available Objectives: Spatial assessment of traffic noise pollution intensity will provide urban planners with approximate estimation of citizens exposure to impermissible sound levels. They could identify critical noise pollution areas wherein noise barriers should be embedded. The present study aims at using the Geographic Information System (GIS to assess spatial changes in traffic noise pollution in Tehran, the capital of Iran, and the largest city in the Middle East. Material and Methods: For this purpose, while measuring equivalent sound levels at different time periods of a day and different days of a week in District 14 of Tehran, wherein there are highways and busy streets, the geographic coordination of the measurement points was recorded at the stations. The obtained results indicated that the equivalent sound level did not show a statistically significant difference between weekdays, and morning, afternoon and evening hours as well as time intervals of 10 min, 15 min and 30 min. Then, 91 stations were selected in the target area and equivalent sound level was measured for each station on 3 occasions of the morning (7:00–9:00 a.m., afternoon (12.00–3:00 p.m. and evening (5:00–8:00 p.m. on Saturdays to Wednesdays. Results: As the results suggest, the maximum equivalent sound level (Leq was reported from Basij Highway, which is a very important connecting thoroughfare in the district, and was equal to 84.2 dB(A, while the minimum equivalent sound level (Leq, measured in the Fajr Hospital, was equal to 59.9 dB(A. Conclusions: The average equivalent sound level was higher than the national standard limit at all stations. The use of sound walls in Highways Basij and Mahallati as well as widening the Streets 17th Shahrivar, Pirouzi and Khavaran, benchmarked on a map, were recommended as the most effective mitigation measures. Additionally, the research findings confirm the outstanding applicability of the Geographic Information System in

  12. Performance analysis of an all-optical OFDM system in presence of non-linear phase noise.

    Science.gov (United States)

    Hmood, Jassim K; Harun, Sulaiman W; Emami, Siamak D; Khodaei, Amin; Noordin, Kamarul A; Ahmad, Harith; Shalaby, Hossam M H

    2015-02-23

    The potential for higher spectral efficiency has increased the interest in all-optical orthogonal frequency division multiplexing (OFDM) systems. However, the sensitivity of all-optical OFDM to fiber non-linearity, which causes nonlinear phase noise, is still a major concern. In this paper, an analytical model for estimating the phase noise due to self-phase modulation (SPM), cross-phase modulation (XPM), and four-wave mixing (FWM) in an all-optical OFDM system is presented. The phase noise versus power, distance, and number of subcarriers is evaluated by implementing the mathematical model using Matlab. In order to verify the results, an all-optical OFDM system, that uses coupler-based inverse fast Fourier transform/fast Fourier transform without any nonlinear compensation, is demonstrated by numerical simulation. The system employs 29 subcarriers; each subcarrier is modulated by a 4-QAM or 16-QAM format with a symbol rate of 25 Gsymbol/s. The results indicate that the phase variance due to FWM is dominant over those induced by either SPM or XPM. It is also shown that the minimum phase noise occurs at -3 dBm and -1 dBm for 4-QAM and 16-QAM, respectively. Finally, the error vector magnitude (EVM) versus subcarrier power and symbol rate is quantified using both simulation and the analytical model. It turns out that both EVM results are in good agreement with each other.

  13. 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

  14. Wick calculus on spaces of generalized functions of compound poisson white noise

    Science.gov (United States)

    Lytvynov, Eugene W.; Rebenko, Alexei L.; Shchepan'ur, Gennadi V.

    1997-04-01

    We derive white noise calculus for a compound Poisson process. Namely, we consider, on the Schwartz space of tempered distributions, S', a measure of compound Poisson white noise, μcp, and construct a whole scale of standard nuclear triples ( Scp) - x ⊃ L2cp) ≡ L2( S', dμcp) ⊃( Scpx, x≥ 0, which are obtained as images under some isomorphism of the corresponding triples centred at a Fock space. It turns out that the most interesting case is x = 1, when our triple coincides with the triple that is constructed by using a system of Appell polynomials in the framework of non-Gaussian biorthogonal analysis. Our special attention is paid to the Wick calculus of the Poisson field, or the quantum compound Poisson white noise process in other terms, which is the family of operators acting from ( Scp) 1 into ( Scp) 1 as multiplication by the compound Poisson white noise ω( t).

  15. Mechanical characteristics of historic mortars from tests on small-sample non-standard on small-sample non-standard specimens

    Czech Academy of Sciences Publication Activity Database

    Drdácký, Miloš; Slížková, Zuzana

    2008-01-01

    Roč. 17, č. 1 (2008), s. 20-29 ISSN 1407-7353 R&D Projects: GA ČR(CZ) GA103/06/1609 Institutional research plan: CEZ:AV0Z20710524 Keywords : small-sample non-standard testing * lime * historic mortar Subject RIV: AL - Art, Architecture, Cultural Heritage

  16. Noise source identification for ducted fan systems

    OpenAIRE

    BENNETT, GARETH; FITZPATRICK, JOHN AIDAN

    2008-01-01

    PUBLISHED Coherence based source analysis techniques can be used to identify the contribution of combustion noise in the exhaust of a jet engine and hence enable the design of noise reduction devices. However, when the combustion noise propagates in a non-linear fashion the identified contribution using ordinary coherence methods will be inaccurate. In this paper, an analysis technique to enable the contribution of linear and non-linear mechanisms to the propagated sound ...

  17. Evaluation of Suitability of Non-Standardized Test Block for Ultrasonic Testing

    International Nuclear Information System (INIS)

    Kwon, Ho Young; Lim, Jong Ho; Kang, Sei Sun

    2000-01-01

    Standard Test Block(STB) for UT(Ultrasonic Testing) is a block approved by authoritative for material, shape and quality. STB is used for characteristic tests, sensitivity calibration and control of the time base range of UT inspection devices. The material, size and chemical components of STB should be strictly controlled to meet the related standards such as ASTM and JIS because it has an effect upon sensitivity, resolution and reproductivity of UT. The STBs which are not approved are sometimes used because the qualified STBs are very expensive. So, the purpose of this study is to survey the characteristics, quality and usability of Non-Standardized Test Blocks. Non-Standardized Test Blocks did not meet the standard requirements in size or chemical components, and ultrasonic characteristics. Therefore if the Non-Standardized Test Blocks are used without being tested, it's likely to cause errors in detecting the location and measuring the size of the defects

  18. Noise Maps for Quantitative and Clinical Severity Towards Long-Term ECG Monitoring.

    Science.gov (United States)

    Everss-Villalba, Estrella; Melgarejo-Meseguer, Francisco Manuel; Blanco-Velasco, Manuel; Gimeno-Blanes, Francisco Javier; Sala-Pla, Salvador; Rojo-Álvarez, José Luis; García-Alberola, Arcadi

    2017-10-25

    Noise and artifacts are inherent contaminating components and are particularly present in Holter electrocardiogram (ECG) monitoring. The presence of noise is even more significant in long-term monitoring (LTM) recordings, as these are collected for several days in patients following their daily activities; hence, strong artifact components can temporarily impair the clinical measurements from the LTM recordings. Traditionally, the noise presence has been dealt with as a problem of non-desirable component removal by means of several quantitative signal metrics such as the signal-to-noise ratio (SNR), but current systems do not provide any information about the true impact of noise on the ECG clinical evaluation. As a first step towards an alternative to classical approaches, this work assesses the ECG quality under the assumption that an ECG has good quality when it is clinically interpretable. Therefore, our hypotheses are that it is possible (a) to create a clinical severity score for the effect of the noise on the ECG, (b) to characterize its consistency in terms of its temporal and statistical distribution, and (c) to use it for signal quality evaluation in LTM scenarios. For this purpose, a database of external event recorder (EER) signals is assembled and labeled from a clinical point of view for its use as the gold standard of noise severity categorization. These devices are assumed to capture those signal segments more prone to be corrupted with noise during long-term periods. Then, the ECG noise is characterized through the comparison of these clinical severity criteria with conventional quantitative metrics taken from traditional noise-removal approaches, and noise maps are proposed as a novel representation tool to achieve this comparison. Our results showed that neither of the benchmarked quantitative noise measurement criteria represent an accurate enough estimation of the clinical severity of the noise. A case study of long-term ECG is reported

  19. Self-regulation of turbulence bursts and transport barriers

    International Nuclear Information System (INIS)

    Floriani, E; Ciraolo, G; Ghendrih, Ph; Sarazin, Y; Lima, R

    2013-01-01

    The interplay between turbulent bursts and transport barriers is analyzed with a simplified model of interchange turbulence in magnetically confined plasmas. The turbulent bursts spread into the transport barriers and, depending on the competing magnitude of the burst and stopping capability of the barrier, can burn through. Simulations of two models of transport barriers are presented: a hard barrier where interchange turbulence modes are stable in a prescribed region and a soft barrier with external plasma biasing. The response of the transport barriers to the non-linear perturbations of the turbulent bursts, addressed in a predator–prey approach, indicates that the barriers monitor an amplification factor of the turbulent bursts, with amplification smaller than one for most bursts and, in some cases, amplification factors that can significantly exceed unity. The weak barriers in corrugated profiles and magnetic structures, as well as the standard barriers, are characterized by these transmission properties, which then regulate the turbulent burst transport properties. The interplays of barriers and turbulent bursts are modeled as competing stochastic processes. For different classes of the probability density function (PDF) of these processes, one can predict the heavy tail properties of the bursts downstream from the barrier, either exponential for a leaky barrier, or with power laws for a tight barrier. The intrinsic probing of the transport barriers by the turbulent bursts thus gives access to the properties of the barriers. The main stochastic variables are the barrier width and the spreading distance of the turbulent bursts within the barrier, together with their level of correlation. One finds that in the case of a barrier with volumetric losses, such as radiation or particle losses as addressed in our present simulations, the stochastic model predicts a leaky behavior with an exponential PDF of escaping turbulent bursts in agreement with the simulation

  20. Provider-related barriers to rapid HIV testing in U.S. urban non-profit community clinics, community-based organizations (CBOs) and hospitals.

    Science.gov (United States)

    Bogart, Laura M; Howerton, Devery; Lange, James; Setodji, Claude Messan; Becker, Kirsten; Klein, David J; Asch, Steven M

    2010-06-01

    We examined provider-reported barriers to rapid HIV testing in U.S. urban non-profit community clinics, community-based organizations (CBOs), and hospitals. 12 primary metropolitan statistical areas (PMSAs; three per region) were sampled randomly, with sampling weights proportional to AIDS case reports. Across PMSAs, all 671 hospitals and a random sample of 738 clinics/CBOs were telephoned for a survey on rapid HIV test availability. Of the 671 hospitals, 172 hospitals were randomly selected for barriers questions, for which 158 laboratory and 136 department staff were eligible and interviewed in 2005. Of the 738 clinics/CBOs, 276 were randomly selected for barriers questions, 206 were reached, and 118 were eligible and interviewed in 2005-2006. In multivariate models, barriers regarding translation of administrative/quality assurance policies into practice were significantly associated with rapid HIV testing availability. For greater rapid testing diffusion, policies are needed to reduce administrative barriers and provide quality assurance training to non-laboratory staff.

  1. Transport barriers in plasmas

    International Nuclear Information System (INIS)

    Caldas, I L; Szezech, J D Jr; Kroetz, T; Marcus, F A; Roberto, M; Viana, R L; Lopes, S R

    2012-01-01

    We discuss the creation of transport barriers in magnetically confined plasmas with non monotonic equilibrium radial profiles. These barriers reduce the transport in the shearless region (i.e., where the twist condition does not hold). For the chaotic motion of particles in an equilibrium electric field with a nonmonotonic radial profile, perturbed by electrostatic waves, we show that a nontwist transport barrier can be created in the plasma by modifying the electric field radial profile. We also show non twist barriers in chaotic magnetic field line transport in the plasma near to the tokamak wall with resonant modes due to electric currents in external coils.

  2. Effects of non-stationary noise on consonant identification

    DEFF Research Database (Denmark)

    Zaar, Johannes; Kowalewski, Borys; Dau, Torsten

    2018-01-01

    recognition scores were inversely related to the amount of simultaneous masking. However, even with minimum simultaneous masking, a substantial loss of consonant recognition was observed at low SNRs, suggesting a forward masking effect. The model, which employs adaptive processes in the front end, accounted...... in such conditions. Normal-hearing listeners were presented with 15 Danish CVs in 5-Hz interrupted noise at SNRs of −20, −10, 0, and 10 dB. Five different CV onset times with respect to the noise bursts were considered, differing in the amount of induced simultaneous and forward masking. As expected, the consonant...

  3. MOOC & B-Learning: Students' Barriers and Satisfaction in Formal and Non-Formal Learning Environments

    Science.gov (United States)

    Gutiérrez-Santiuste, Elba; Gámiz-Sánchez, Vanesa-M.; Gutiérrez-Pérez, Jose

    2015-01-01

    The study presents a comparative analysis of two virtual learning formats: one non-formal through a Massive Open Online Course (MOOC) and the other formal through b-learning. We compare the communication barriers and the satisfaction perceived by the students (N = 249) by developing a qualitative analysis using semi-structured questionnaires and…

  4. Noise-induced hearing loss and combined noise and vibration exposure.

    Science.gov (United States)

    Turcot, A; Girard, S A; Courteau, M; Baril, J; Larocque, R

    2015-04-01

    While there is a wide body of literature addressing noise-induced hearing loss (NIHL) and hand-arm vibration syndrome (HAVS) independently, relatively few studies have considered the combined effects of noise and vibration. These studies have suggested an increased risk of NIHL in workers with vibration white finger (VWF), though the relationship remains poorly understood. To determine whether hearing impairment is worse in noise-exposed workers with VWF than in workers with similar noise exposures but without VWF. The Quebec National Institute of Public Health audiometric database was used in conjunction with work-related accident and occupational diseases data from the Quebec workers' compensation board to analyse differences in audiometry results between vibration-exposed workers in the mining and forestry industries and the overall source population, and between mining and forestry workers with documented VWF and those without VWF. The International Organization for Standardization (ISO) 7029 standards were used to calculate hearing loss not attributable to age. 15751 vibration-exposed workers were identified in an overall source population of 59339. Workers with VWF (n = 96) had significantly worse hearing at every frequency studied (500, 1000, 2000 4000 Hz) compared with other mining and forestry workers without VWF. This study confirms previous findings of greater hearing loss at higher frequencies in workers with VWF, but also found a significant difference in hearing loss at low frequencies. It therefore supports the association between combined noise and hand-arm vibration (HAV) exposure and NIHL. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. 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...

  6. Search for non-standard SUSY signatures in CMS

    International Nuclear Information System (INIS)

    Teyssier, Daniel

    2008-01-01

    New studies of the CMS collaboration are presented on the sensitivity to searches for non-standard signatures of particular SUSY scenarios. These signatures include non-pointing photons as well as pairs of prompt photons as expected GMSB SUSY models, as well as heavy stable charged particles produced in split supersymmetry models, long lived staus from GMSB SUSY and long lived stops in other SUSY scenarios. Detailed detector simulation is used for the study, and all relevant Standard Model background and detector effects that can mimic these special signatures are included. It is shown that with already with less than 100 pb -1 the CMS sensitivity will probe an interesting as yet by data unexplored parameter range of these models.

  7. 49 CFR 229.121 - Locomotive cab noise.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Locomotive cab noise. 229.121 Section 229.121... § 229.121 Locomotive cab noise. (a) Performance standards for locomotives. (1) When tested for static noise in accordance with paragraph (a)(3) of this section, all locomotives of each design or model that...

  8. Moment Lyapunov Exponent and Stochastic Stability of Binary Airfoil under Combined Harmonic and Non-Gaussian Colored Noise Excitations

    Science.gov (United States)

    Hu, D. L.; Liu, X. B.

    Both periodic loading and random forces commonly co-exist in real engineering applications. However, the dynamic behavior, especially dynamic stability of systems under parametric periodic and random excitations has been reported little in the literature. In this study, the moment Lyapunov exponent and stochastic stability of binary airfoil under combined harmonic and non-Gaussian colored noise excitations are investigated. The noise is simplified to an Ornstein-Uhlenbeck process by applying the path-integral method. Via the singular perturbation method, the second-order expansions of the moment Lyapunov exponent are obtained, which agree well with the results obtained by the Monte Carlo simulation. Finally, the effects of the noise and parametric resonance (such as subharmonic resonance and combination additive resonance) on the stochastic stability of the binary airfoil system are discussed.

  9. Barriers to standard precautions adherence in a dental school in Iran: a qualitative study.

    Science.gov (United States)

    Hedayati, Hamidreza; Marjadi, Brahmaputra; Askarian, Mehrdad

    2014-07-01

    Setting up good infection control practices in educational institutions is crucial in shaping future health professionals. The implementation of standard precautions (SPs) in Iranian dental schools has not been explored qualitatively to identify barriers to good practice. Twelve focus group discussions and 8 semistructured interviews were conducted with students, residents, and staff members (n = 83) of the Shiraz University of Medical Sciences Dental School. The interview guide addressed performance, subjective norms, and behavioral control domains of SP-related behaviors. Thematic analysis was performed manually to identify barriers to SP practices. Proximal factors of poor SP adherence were a lack of knowledge and technical difficulties. These factors were compounded by intermediate factors in the work environment: lack of facilities, heavy workload, patient expectations, interprofessional conflicts, and lack of good role models. Two underlying distal factors were financial issues and unsupportive organizational culture. The social constructionism theory was useful in analyzing the situation and suggesting an educational approach as part of the solution. Complex and intertwined barriers of SP adherence were found in this dental school. A social construction approach may assist in addressing these problems by shifting the culture through education to construct a contextual new knowledge. Further research in medical sociology of SP practices would be useful. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  10. Searches for non-Standard Model Higgs bosons

    CERN Document Server

    Dumitriu, Ana Elena; The ATLAS collaboration

    2018-01-01

    This presentation focuses on the Searches for non-Standard Model Higgs bosons using 36.1 fb of data collected by the ATLAS experiment. There are several theoretical models with an extended Higgs sector considered: 2 Higgs Doublet Models (2HDM), Supersymmetry (SUSY), which brings along super-partners of the SM particles (+ The Minimal Supersymmetric Standard Model (MSSM), whose Higgs sector is equivalent to the one of a constrained 2HDM of type II and the next-to MSSM (NMSSM)), General searches and Invisible decaying Higgs boson.

  11. Saturated Resin Ectopic Regeneration by Non-Thermal Dielectric Barrier Discharge Plasma

    Directory of Open Access Journals (Sweden)

    Chunjing Hao

    2017-11-01

    Full Text Available Textile dyes are some of the most refractory organic compounds in the environment due to their complex and various structure. An integrated resin adsorption/Dielectric Barrier Discharge (DBD plasma regeneration was proposed to treat the indigo carmine solution. It is the first time to report ectopic regeneration of the saturated resins by non-thermal Dielectric Barrier Discharge. The adsorption/desorption efficiency, surface functional groups, structural properties, regeneration efficiency, and the intermediate products between gas and liquid phase before and after treatment were investigated. The results showed that DBD plasma could maintain the efficient adsorption performance of resins while degrading the indigo carmine adsorbed by resins. The degradation rate of indigo carmine reached 88% and the regeneration efficiency (RE can be maintained above 85% after multi-successive regeneration cycles. The indigo carmine contaminants were decomposed by a variety of reactive radicals leading to fracture of exocyclic C=C bond, which could cause decoloration of dye solution. Based on above results, a possible degradation pathway for the indigo carmine by resin adsorption/DBD plasma treatment was proposed.

  12. Phosphate barrier on pore-filled cation-exchange membrane for blocking complexing ions in presence of non-complexing ions

    Science.gov (United States)

    Chavan, Vivek; Agarwal, Chhavi; Shinde, Rakesh N.

    2018-06-01

    In present work, an approach has been used to form a phosphate groups bearing surface barrier on a cation-exchange membrane (CEM). Using optimized conditions, the phosphate bearing monomer bis[2-(methacryloyloxy)ethyl] phosphate has been grafted on the surface of the host poly(ethersulfone) membranes using UV light induced polymerization. The detailed characterizations have shown that less than a micron layer of phosphate barrier is formed without disturbing the original microporous structure of the host membrane. The pores of thus formed membrane have been blocked by cationic-gel formed by in situ UV-initiator induced polymerization of 2-acrylamido-2-methyl-1-propane sulphonic acid along with crosslinker ethylene glycol dimethacrylate in the pores of the membrane. UV-initiator is required for pore-filling as UV light would not penetrate the interior matrix of the membrane. The phosphate functionalized barrier membrane has been examined for permselectivity using a mixture of representative complexing Am3+ ions and non-complexing Cs+ ions. This experiment has demonstrated that complex forming Am3+ ions are blocked by phosphate barrier layer while non-complexing Cs+ ions are allowed to pass through the channels formed by the crosslinked cationic gel.

  13. Barriers to oral health care utilization in Ibadan, South West Nigeria ...

    African Journals Online (AJOL)

    Background: Barriers to oral health utilization are many, but those that are significant for our environment are not yet clear. The current study was designed ... Fear of dental injection, cost of treatment, feeling of insecurity when the dentist is operating and disturbing noise from dental drill were the major barriers. There was a ...

  14. Cardiovascular effects of environmental noise: Research in Austria

    Directory of Open Access Journals (Sweden)

    Peter Lercher

    2011-01-01

    Full Text Available Cardiovascular effects of noise rank second in terms of disability-adjusted life year (DALYs after annoyance. Although research during the past decade has consolidated the available data base, the most recent meta-analysis still shows wide confidence intervals - indicating imprecise information for public health risk assessment. The alpine area of Tyrol in the Austrian part of the Alps has experienced a massive increase in car and heavy goods traffic (road and rail during the last 35 years. Over the past 25 years small-, middle-, and large-sized epidemiological health surveys have been conducted - mostly within the framework of environmental health impact assessments. By design, these studies have emphasized a contextually driven environmental stress perspective, where the adverse health effects on account of noise are studied in a broader framework of environmental health, susceptibility, and coping. Furthermore, innovative exposure assessment strategies have been implemented. This article reviews the existing knowledge from these studies over time, and presents the exposure-response curves, with and without interaction assessment, based on standardized re-analyses and discusses it in the light of past and current cardiovascular noise effects research. The findings support relevant moderation by age, gender, and family history in nearly all studies and suggest a strong need for consideration of non-linearity in the exposure-response analyses. On the other hand, air pollution has not played a relevant role as a moderator in the noise-hypertension or the noise-angina pectoris relationship. Finally, different noise modeling procedures can introduce variations in the exposure response curves, with substantive consequences for public health risk assessment of noise exposure.

  15. Stereodynamic tetrahydrobiisoindole “NU-BIPHEP(O”s: functionalization, rotational barriers and non-covalent interactions

    Directory of Open Access Journals (Sweden)

    Golo Storch

    2016-07-01

    Full Text Available Stereodynamic ligands offer intriguing possibilities in enantioselective catalysis. “NU-BIPHEPs” are a class of stereodynamic diphosphine ligands which are easily accessible via rhodium-catalyzed double [2 + 2 + 2] cycloadditions. This study explores the preparation of differently functionalized “NU-BIPHEP(O” compounds, the characterization of non-covalent adduct formation and the quantification of enantiomerization barriers. In order to explore the possibilities of functionalization, we studied modifications of the ligand backbone, e.g., with 3,5-dichlorobenzoyl chloride. Diastereomeric adducts with Okamoto-type cellulose derivatives and on-column deracemization were realized on the basis of non-covalent interactions. Enantioselective dynamic HPLC (DHPLC allowed for the determination of rotational barriers of ΔG‡298K = 92.2 ± 0.3 kJ mol−1 and 99.5 ± 0.1 kJ mol−1 underlining the stereodynamic properties of “NU-BIPHEPs” and “NU-BIPHEP(Os”, respectively. These results make the preparation of tailor-made functionalized stereodynamic ligands possible and give an outline for possible applications in enantioselective catalysis.

  16. Signal to noise ratio (SNR) and image uniformity: an estimate of performance of magnetic resonance imaging (MRI) system

    International Nuclear Information System (INIS)

    Narayan, P.; Suri, S.; Choudhary, S.R.

    2001-01-01

    In most general definition, noise in an image, is any variation that represents a deviation from truth. Noise sources in MRI can be systematic or random and statistical in nature. Data processing algorithms that smooth and enhance the edges by non-linear intensity assignments among other factors can affect the distribution of statistical noise. The SNR and image uniformity depends on the various parameters of NMR imaging system (viz. General system calibration, Gain coil tuning, AF shielding, coil loading, image processing and scan parameters like TE, TR, interslice distance, slice thickness, pixel size and matrix size). A study on SNR and image uniformity have been performed using standard head AF coil with different TR and the estimates of their variation are presented. A comparison between different techniques has also been evaluated using standard protocol of the Siemens Magnetom Vision Plus MRI system

  17. Barriers to cross--institutional health information exchange: a literature review.

    Science.gov (United States)

    Edwards, Ashley; Hollin, Ilene; Barry, Jeffrey; Kachnowski, Stan

    2010-01-01

    While the development of health information technology, particularly electronic health records (EHR), is a triumph for the advancement of healthcare, non-interoperable clinical data systems lead to fragmented communication and incomplete records. If interoperable HIT systems could be achieved integrated HIT could be leveraged to lessen medical errors, improve patient care and optimize epidemiological research. To understand the barriers to interoperability or health information exchange (HIE), we reviewed the literature on HIT and barriers to HIE. Our search yielded 492 articles, 25 meeting our inclusion criteria. In general, we found that the predominant barriers to HIE are need for standards, security concerns, economic loss to competitors, and federated systems. Research on interoperability is limited because most HIE programs are still in formative stages. More research is needed to fully understand interoperability of HIT, how to overcome the barriers to interoperability, and how to design HIT to better facilitate HIE.

  18. Non-Geiger-Mode Single-Photon Avalanche Detector with Low Excess Noise

    Science.gov (United States)

    Zhao, Kai; Lo, YuHwa; Farr, William

    2010-01-01

    This design constitutes a self-resetting (gain quenching), room-temperature operational semiconductor single-photon-sensitive detector that is sensitive to telecommunications optical wavelengths and is scalable to large areas (millimeter diameter) with high bandwidth and efficiencies. The device can detect single photons at a 1,550-nm wavelength at a gain of 1 x 10(exp 6). Unlike conventional single photon avalanche detectors (SPADs), where gain is an extremely sensitive function to the bias voltage, the multiplication gain of this device is stable at 1 x 10(exp 6) over a wide range of bias from 30.2 to 30.9 V. Here, the multiplication gain is defined as the total number of charge carriers contained in one output pulse that is triggered by the absorption of a single photon. The statistics of magnitude of output signals also shows that the device has a very narrow pulse height distribution, which demonstrates a greatly suppressed gain fluctuation. From the histograms of both pulse height and pulse charge, the equivalent gain variance (excess noise) is between 1.001 and 1.007 at a gain of 1 x 10(exp 6). With these advantages, the device holds promise to function as a PMT-like photon counter at a 1,550- nm wavelength. The epitaxial layer structure of the device allows photons to be absorbed in the InGaAs layer, generating electron/hole (e-h) pairs. Driven by an electrical field in InGaAs, electrons are collected at the anode while holes reach the multiplication region (InAlAs p-i-n structure) and trigger the avalanche process. As a result, a large number of e-h pairs are created, and the holes move toward the cathode. Holes created by the avalanche process gain large kinetic energy through the electric field, and are considered hot. These hot holes are cooled as they travel across a p -InAlAs low field region, and are eventually blocked by energy barriers formed by the InGaAsP/ InAlAs heterojunctions. The composition of the InGaAsP alloy was chosen to have an 80 me

  19. Environmental propagation of noise in mines and nearby villages: A study through noise mapping

    Directory of Open Access Journals (Sweden)

    Veena D Manwar

    2016-01-01

    Full Text Available Background: Noise mapping being an established practice in Europe is hardly practiced for noise management in India although it is mandatory in Indian mines as per guidelines of the Directorate General of Mines Safety (DGMS. As a pilot study, noise mapping was conducted in an opencast mine with three different models; one based on the baseline operating conditions in two shifts (Situation A, and two other virtual situations where either production targets were enhanced by extending working hours to three shifts (Situation B or only by increased mechanization and not changing the duration of work (Situation C. Methods: Noise sources were categorized as point, line, area, and moving sources. Considering measured power of the sources, specific meteorological and geographical parameters, noise maps were generated using Predictor LimA software. Results: In all three situations, Lden values were 95 dB(A and 70–80 dB(A near drill machine and haul roads, respectively. Noise contours were wider in Situation C due to increase in frequency of dumpers. Lden values near Shovel 1 and Shovel 2 under Situation B increased by 5 dB and 3 dB, respectively due to expansion of working hours. In Situation C, noise levels were >82 dB(A around shovels. Noise levels on both sides of conveyor belts were in the range of 80–85 dB(A in Situations A and C whereas it was 85–90 dB(A in Situation B. Near crusher plants, it ranged from 80 to 90 dB(A in Situations A and C and between 85 and 95 dB(A in Situation B. In all situations, noise levels near residential areas exceeded the Central Pollution Control Board (CPCB limits, i.e., 55 dB(A. Conclusions: For all situations, predicted noise levels exceeded CPCB limits within the mine and nearby residential area. Residential areas near the crusher plants are vulnerable to increased noise propagation. It is recommended to put an acoustic barrier near the crusher plant to attenuate the noise propagation.

  20. Workshop on CP Studies and Non-Standard Higgs Physics

    CERN Document Server

    Accomando, E.; Akhmetzyanova, E.; Albert, J.; Alves, A.; Amapane, N.; Aoki, M.; Azuelos, G.; Baffioni, S.; Ballestrero, A.; Barger, V.; Bartl, A.; Bechtle, P.; Blanger, G.; Belhouari, A.; Bellan, R.; Belyaev, A.; Benes, Petr; Benslama, K.; Bernreuther, W.; Besanon, M.; Bevilacqua, G.; Beyer, M.; Bluj, M.; Bolognesi, S.; Boonekamp, M.; Borzumati, Francesca; Boudjema, F.; Brandenburg, A.; Brauner, Tomas; Buszello, C.P.; Butterworth, J.M.; Carena, Marcela; Cavalli, D.; Cerminara, G.; Choi, S.Y.; Clerbaux, B.; Collard, C.; Conley, John A.; Deandrea, A.; De Curtis, S.; Dermisek, R.; De Roeck, A.; Dewhirst, G.; Diaz, M.A.; Diaz-Cruz, J.L.; Dietrich, D.D.; Dolgopolov, M.; Dominici, D.; Dubinin, M.; Eboli, O.; Ellis, John R.; Evans, N.; Fano, L.; Ferland, J.; Ferrag, S.; Fitzgerald, S.P.; Fraas, H.; Franke, F.; Gennai, S.; Ginzburg, I.F.; Godbole, R.M.; Gregoire, T.; Grenier, Gerald Jean; Grojean, C.; Gudnason, S.B.; Gunion, J.F.; Haber, H.E.; Hahn, T.; Han, T.; Hankele, V.; Hays, Christopher Paul; Heinemeyer, S.; Hesselbach, S.; Hewett, J.L.; Hidaka, K.; Hirsch, M.; Hollik, W.; Hooper, D.; Hosek, J.; Hubisz, J.; Hugonie, C.; Kalinowski, J.; Kanemura, S.; Kashkan, V.; Kernreiter, T.; Khater, W.; Khoze, V.A.; Kilian, W.; King, S.F.; Kittel, O.; Klamke, G.; Kneur, J.L.; Kouvaris, C.; Kraml, S.; Krawczyk, M.; Krstonoic, P.; Kyriakis, A.; Langacker, P.; Le, M.P.; Lee, H.-S.; Lee, J.S.; Lemaire, M.C.; Liao, Y.; Lillie, B.; Litvine, Vladimir A.; Logan, H.E.; McElrath, Bob; Mahmoud, T.; Maina, E.; Mariotti, C.; Marquard, P.; Martin, A.D.; Mazumdar, K.; Miller, D.J.; Min, P.; Monig, Klaus; Moortgat-Pick, G.; Moretti, S.; Muhlleitner, M.M.; Munir, S.; Nevzorov, R.; Newman, H.; Niezurawski, P.; Nikitenko, A.; Noriega-Papaqui, R.; Okada, Y.; Osland, P.; Pilaftsis, A.; Porod, W.; Przysiezniak, H.; Pukhov, A.; Rainwater, D.; Raspereza, A.; Reuter, J.; Riemann, S.; Rindani, S.; Rizzo, T.G.; Ros, E.; Rosado, A.; Rousseau, D.; Roy, D.P.; Ryskin, M.G.; Rzehak, H.; Sannino, F.; Schmidt, E.; Schrder, H.; Schumacher, M.; Semenov, A.; Senaha, E.; Shaughnessy, G.; Singh, R.K.; Terning, J.; Vacavant, L.; Velasco, M.; Villanova del Moral, Albert; von der Pahlen, F.; Weiglein, G.; Williams, J.; Williams, K.E.; Zarnecki, A.F.; Zeppenfeld, D.; Zerwas, D.; Zerwas, P.M.; Zerwekh, A.R.; Ziethe, J.; 2nd Workshop on CP Studies and Non-standard Higgs Physics; 3rd Workshop on CP Studies and Non-standard Higgs Physics; 4th Workshop on CP Studies and Non-standard Higgs Physics; CPNSH; Workshop on CP Studies and Non-standard Higgs Physics; CP Studies and Non-Standard Higgs Physics

    2006-01-01

    There are many possibilities for new physics beyond the Standard Model that feature non-standard Higgs sectors. These may introduce new sources of CP violation, and there may be mixing between multiple Higgs bosons or other new scalar bosons. Alternatively, the Higgs may be a composite state, or there may even be no Higgs at all. These non-standard Higgs scenarios have important implications for collider physics as well as for cosmology, and understanding their phenomenology is essential for a full comprehension of electroweak symmetry breaking. This report discusses the most relevant theories which go beyond the Standard Model and its minimal, CP-conserving supersymmetric extension: two-Higgs-doublet models and minimal supersymmetric models with CP violation, supersymmetric models with an extra singlet, models with extra gauge groups or Higgs triplets, Little Higgs models, models in extra dimensions, and models with technicolour or other new strong dynamics. For each of these scenarios, this report presents ...

  1. British Thoracic Society Quality Standards for acute non-invasive ventilation in adults

    Science.gov (United States)

    Davies, Michael; Allen, Martin; Bentley, Andrew; Bourke, Stephen C; Creagh-Brown, Ben; D’Oliveiro, Rachel; Glossop, Alastair; Gray, Alasdair; Jacobs, Phillip; Mahadeva, Ravi; Moses, Rachael; Setchfield, Ian

    2018-01-01

    Introduction The purpose of the quality standards document is to provide healthcare professionals, commissioners, service providers and patients with a guide to standards of care that should be met for the provision of acute non-invasive ventilation in adults together with measurable markers of good practice. Methods Development of British Thoracic Society (BTS) Quality Standards follows the BTS process of quality standard production based on the National Institute for Health and Care Excellence process manual for the development of quality standards. Results 6 quality statements have been developed, each describing a standard of care for the provision of acute non-invasive ventilation in the UK, together with measurable markers of good practice. Conclusion BTS Quality Standards for acute non-invasive ventilation in adults form a key part of the range of supporting materials that the Society produces to assist in the dissemination and implementation of guideline’s recommendations. PMID:29636979

  2. Motivators of and Barriers to Engagement in Healthy Eating Behaviors among non-Hispanic Black Adults.

    Science.gov (United States)

    Nolan, Sarah E M; Tucker, Carolyn M; Flenar, Delphia J; Arthur, Tya M; Smith, Tasia M

    2016-09-01

    The objective of this study was to determine if non-Hispanic Black adults' levels of endorsement of motivators and barriers related to healthy eating are significantly associated with their level of engagement in healthy eating and their perceived importance of healthy eating and if these investigated variables differ by gender, income, and/or age. An assessment battery was completed by a cross-sectional sample of 207 non-Hispanic Black adults in Bronx, NY (54.1 % female; age: M = 38, SD = 14.12). Participants were recruited by culturally diverse data collectors at community-based locations within Bronx. Building healthy eating into a routine was a significant motivator of healthy eating (p motivators to engaging in healthy eating (routine: p motivators and barriers. Intervention programs to increase healthy eating among adults similar to those in this study may benefit from including a focus on increasing self-control of eating behaviors and incorporating healthy eating into one's routine.

  3. Spatial traffic noise pollution assessment - A case study.

    Science.gov (United States)

    Monazzam, Mohammad Reza; Karimi, Elham; Abbaspour, Majid; Nassiri, Parvin; Taghavi, Lobat

    2015-01-01

    Spatial assessment of traffic noise pollution intensity will provide urban planners with approximate estimation of citizens exposure to impermissible sound levels. They could identify critical noise pollution areas wherein noise barriers should be embedded. The present study aims at using the Geographic Information System (GIS) to assess spatial changes in traffic noise pollution in Tehran, the capital of Iran, and the largest city in the Middle East. For this purpose, while measuring equivalent sound levels at different time periods of a day and different days of a week in District 14 of Tehran, wherein there are highways and busy streets, the geographic coordination of the measurement points was recorded at the stations. The obtained results indicated that the equivalent sound level did not show a statistically significant difference between weekdays, and morning, afternoon and evening hours as well as time intervals of 10 min, 15 min and 30 min. Then, 91 stations were selected in the target area and equivalent sound level was measured for each station on 3 occasions of the morning (7:00-9:00 a.m.), afternoon (12.00-3:00 p.m.) and evening (5:00-8:00 p.m.) on Saturdays to Wednesdays. As the results suggest, the maximum equivalent sound level (Leq) was reported from Basij Highway, which is a very important connecting thoroughfare in the district, and was equal to 84.2 dB(A), while the minimum equivalent sound level (Leq), measured in the Fajr Hospital, was equal to 59.9 dB(A). The average equivalent sound level was higher than the national standard limit at all stations. The use of sound walls in Highways Basij and Mahallati as well as widening the Streets 17th Shahrivar, Pirouzi and Khavaran, benchmarked on a map, were recommended as the most effective mitigation measures. Additionally, the research findings confirm the outstanding applicability of the Geographic Information System in handling noise pollution data towards depicting noise pollution intensity caused

  4. Dynamic responses of connections in road safety barriers

    International Nuclear Information System (INIS)

    Bayton, D.A.F.; Long, R.; Fourlaris, G.

    2009-01-01

    Bolted road safety barrier connections utilise slotted holes that are perpendicular to the direction of the safety barrier beam. Due to the clearance between the slotted holes and the bolts, a varying amount of slippage is seen before contact with the edge of the slot is made. The stiffness characteristics of bolted road safety barrier connections have been examined with a representative test coupon that incorporates a full size safety barrier connection slot to industry standard dimensions. Previous research work has successfully determined the stiffness characteristics of the bolted connections at quasi-static strain rates. Representative non-linear finite element models of the bolted test coupons have been constructed. When compared to the laboratory results the initial stiffness, maximum force and displacement of the bolted connections are similar to the finite element model predictions. Current investigations have moved onto strain rates comparable to those observed in actual vehicle crash tests. Explicit dynamic finite element (FE) models have been constructed and validated, using experimental data produced using a series of high strain rate laboratory tests for a number of bolt configurations

  5. 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.

  6. Non-Power Reactor Operator Licensing Examiner Standards

    International Nuclear Information System (INIS)

    1994-06-01

    The Non-Power Reactor Operator Licensing Examiner Standards provide policy and guidance to NRC examiners and establish the procedures and practices for examining and licensing of applicants for NRC operator licenses pursuant to Part 55 of Title 10 of the Code of Federal Regulations (10 CFR Part 55). They are intended to assist NRC examiners and facility licensees to understand the examination process better and to provide for equitable and consistent administration of examinations to all applicants by NRC examiners. These standards are not a substitute for the operator licensing regulations and are subject to revision or other internal operator examination licensing policy changes. As appropriate, this standard will be revised periodically to accommodate comments and reflect new information or experience

  7. Noise in strong laser-atom interactions: Phase telegraph noise

    International Nuclear Information System (INIS)

    Eberly, J.H.; Wodkiewicz, K.; Shore, B.W.

    1984-01-01

    We discuss strong laser-atom interactions that are subjected to jump-type (random telegraph) random-phase noise. Physically, the jumps may arise from laser fluctuations, from collisions of various kinds, or from other external forces. Our discussion is carried out in two stages. First, direct and partially heuristic calculations determine the laser spectrum and also give a third-order differential equation for the average inversion of a two-level atom on resonance. At this stage a number of general features of the interaction are able to be studied easily. The optical analog of motional narrowing, for example, is clearly predicted. Second, we show that the theory of generalized Poisson processes allows laser-atom interactions in the presence of random telegraph noise of all kinds (not only phase noise) to be treated systematically, by means of a master equation first used in the context of quantum optics by Burshtein. We use the Burshtein equation to obtain an exact expression for the two-level atom's steady-state resonance fluorescence spectrum, when the exciting laser exhibits phase telegraph noise. Some comparisons are made with results obtained from other noise models. Detailed treatments of the effects ofmly jumps, or as a model of finite laser bandwidth effects, in which the laser frequency exhibits random jumps. We show that these two types of frequency noise can be distinguished in light-scattering spectra. We also discuss examples which demonstrate both temporal and spectral motional narrowing, nonexponential correlations, and non-Lorentzian spectra. Its exact solubility in finite terms makes the frequency-telegraph noise model an attractive alternative to the white-noise Ornstein-Uhlenbeck frequency noise model which has been previously applied to laser-atom interactions

  8. P3a from white noise.

    Science.gov (United States)

    Frank, David W; Yee, Ryan B; Polich, John

    2012-08-01

    P3a and P3b event-related brain potentials (ERPs) were elicited with an auditory three-stimulus (target, distracter, and standard) discrimination task in which subjects responded only to the target. Distracter stimuli consisted of white noise or novel sounds with stimulus characteristics perceptually matched. Target/standard discrimination difficulty was manipulated by varying target/standard pitch differences to produce relatively easy, medium, and hard tasks. Error rate and response time increased with increases in task difficulty. P3a was larger for the white noise compared to novel sounds, maximum over the central/parietal recording sites, and did not differ in size across difficulty levels. P3b was unaffected by distracter type, decreased as task difficulty increased, and maximum over the parietal recording sites. The findings indicate that P3a from white noise is robust and should be useful for applied studies as it removes stimulus novelty variability. Theoretical perspectives are discussed. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Effects of time pressure and noise on non-destructive testing

    Energy Technology Data Exchange (ETDEWEB)

    Enkvist, J.; Svenson, Ola [Stockholm Univ. (Sweden). Dept. of Psychology; Edland, A. [Swedish Nuclear Power Inspectorate, Stockholm (Sweden)

    2001-12-01

    Manual ultrasonic testing (UT) is the most frequently used non-destructive testing (NDT) method for in-service inspection of components important to safety and/or plant availability. Earlier, great variations have been found in operator performance, often attributed to operator fatigue. However, no conclusive findings have been reported. According to the Yerkes-Dodson law there is an optimal arousal level where performance is highest, for simple tasks this optimum is higher than for more complex tasks. In the present study twenty operators performed manual ultrasonic inspections of six test pieces with manufactured flaws. The operators performed the inspections under stress (high arousal - time pressure and noise) and non-stress conditions; one condition the first day and the other the second and last day. It was hypothesised that the stress condition led to a level of arousal so high that it would affect the results negatively. The results confirmed that the operators were affected by the stress condition. However, contrary to the hypotheses it was found that the manipulation increased operator performance. Operators with the stress condition the first day performed better than the other operators did (under both the stress and the non-stress condition). This was interpreted as the 'stress first' (group 1) operators had established efficient performance patterns the first day - affecting also the second day. Operators beginning with stress condition also tended to be more motivated. It was concluded that operator performance is affected by arousal. The operators with non-stress first (group 2) worked hard with the complex task but their arousal level was assumed to be above the optimal, resulting in a low hit rate.

  10. Effects of time pressure and noise on non-destructive testing

    Energy Technology Data Exchange (ETDEWEB)

    Enkvist, J; Svenson, Ola [Stockholm Univ. (Sweden). Dept. of Psychology; Edland, A [Swedish Nuclear Power Inspectorate, Stockholm (Sweden)

    2001-12-01

    Manual ultrasonic testing (UT) is the most frequently used non-destructive testing (NDT) method for in-service inspection of components important to safety and/or plant availability. Earlier, great variations have been found in operator performance, often attributed to operator fatigue. However, no conclusive findings have been reported. According to the Yerkes-Dodson law there is an optimal arousal level where performance is highest, for simple tasks this optimum is higher than for more complex tasks. In the present study twenty operators performed manual ultrasonic inspections of six test pieces with manufactured flaws. The operators performed the inspections under stress (high arousal - time pressure and noise) and non-stress conditions; one condition the first day and the other the second and last day. It was hypothesised that the stress condition led to a level of arousal so high that it would affect the results negatively. The results confirmed that the operators were affected by the stress condition. However, contrary to the hypotheses it was found that the manipulation increased operator performance. Operators with the stress condition the first day performed better than the other operators did (under both the stress and the non-stress condition). This was interpreted as the 'stress first' (group 1) operators had established efficient performance patterns the first day - affecting also the second day. Operators beginning with stress condition also tended to be more motivated. It was concluded that operator performance is affected by arousal. The operators with non-stress first (group 2) worked hard with the complex task but their arousal level was assumed to be above the optimal, resulting in a low hit rate.

  11. Effects of time pressure and noise on non-destructive testing

    International Nuclear Information System (INIS)

    Enkvist, J.; Svenson, Ola

    2001-12-01

    Manual ultrasonic testing (UT) is the most frequently used non-destructive testing (NDT) method for in-service inspection of components important to safety and/or plant availability. Earlier, great variations have been found in operator performance, often attributed to operator fatigue. However, no conclusive findings have been reported. According to the Yerkes-Dodson law there is an optimal arousal level where performance is highest, for simple tasks this optimum is higher than for more complex tasks. In the present study twenty operators performed manual ultrasonic inspections of six test pieces with manufactured flaws. The operators performed the inspections under stress (high arousal - time pressure and noise) and non-stress conditions; one condition the first day and the other the second and last day. It was hypothesised that the stress condition led to a level of arousal so high that it would affect the results negatively. The results confirmed that the operators were affected by the stress condition. However, contrary to the hypotheses it was found that the manipulation increased operator performance. Operators with the stress condition the first day performed better than the other operators did (under both the stress and the non-stress condition). This was interpreted as the 'stress first' (group 1) operators had established efficient performance patterns the first day - affecting also the second day. Operators beginning with stress condition also tended to be more motivated. It was concluded that operator performance is affected by arousal. The operators with non-stress first (group 2) worked hard with the complex task but their arousal level was assumed to be above the optimal, resulting in a low hit rate

  12. Acoustic-noise-optimized diffusion-weighted imaging.

    Science.gov (United States)

    Ott, Martin; Blaimer, Martin; Grodzki, David M; Breuer, Felix A; Roesch, Julie; Dörfler, Arnd; Heismann, Björn; Jakob, Peter M

    2015-12-01

    This work was aimed at reducing acoustic noise in diffusion-weighted MR imaging (DWI) that might reach acoustic noise levels of over 100 dB(A) in clinical practice. A diffusion-weighted readout-segmented echo-planar imaging (EPI) sequence was optimized for acoustic noise by utilizing small readout segment widths to obtain low gradient slew rates and amplitudes instead of faster k-space coverage. In addition, all other gradients were optimized for low slew rates. Volunteer and patient imaging experiments were conducted to demonstrate the feasibility of the method. Acoustic noise measurements were performed and analyzed for four different DWI measurement protocols at 1.5T and 3T. An acoustic noise reduction of up to 20 dB(A) was achieved, which corresponds to a fourfold reduction in acoustic perception. The image quality was preserved at the level of a standard single-shot (ss)-EPI sequence, with a 27-54% increase in scan time. The diffusion-weighted imaging technique proposed in this study allowed a substantial reduction in the level of acoustic noise compared to standard single-shot diffusion-weighted EPI. This is expected to afford considerably more patient comfort, but a larger study would be necessary to fully characterize the subjective changes in patient experience.

  13. Cable-to-post attachments for use in non-proprietary high-tension cable median barrier - phase II.

    Science.gov (United States)

    2016-03-24

    The objective of this study was to reevaluate and improve the existing cable-to-post attachment hardware that is utilized : in the non-proprietary cable barrier being developed at MwRSF. The study focused on redesigning the bolted, tabbed : bracket (...

  14. Dynamical reduction models with general gaussian noises

    International Nuclear Information System (INIS)

    Bassi, Angelo; Ghirardi, GianCarlo

    2002-02-01

    We consider the effect of replacing in stochastic differential equations leading to the dynamical collapse of the statevector, white noise stochastic processes with non white ones. We prove that such a modification can be consistently performed without altering the most interesting features of the previous models. One of the reasons to discuss this matter derives from the desire of being allowed to deal with physical stochastic fields, such as the gravitational one, which cannot give rise to white noises. From our point of view the most relevant motivation for the approach we propose here derives from the fact that in relativistic models the occurrence of white noises is the main responsible for the appearance of untractable divergences. Therefore, one can hope that resorting to non white noises one can overcome such a difficulty. We investigate stochastic equations with non white noises, we discuss their reduction properties and their physical implications. Our analysis has a precise interest not only for the above mentioned subject but also for the general study of dissipative systems and decoherence. (author)

  15. Directory of DOE and contractor personnel involved in non-government standards activities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    This document contains a listing of DOE employees and DOE contractors who have submitted form DOE F 1300.2, Record of Non-Government Standards Activity. Additional names were added from rosters supplied by non-Government standards bodies.

  16. NASA's Pursuit of Low-Noise Propulsion for Low-Boom Commercial Supersonic Vehicles

    Science.gov (United States)

    Bridges, James; Brown, Clifford A.; Seidel, Jonathan A.

    2018-01-01

    Since 2006, when the Fundamental Aeronautics Program was instituted within NASA's Aeronautics Mission Directorate, there has been a Project looking at the technical barriers to commercial supersonic flight. Among the barriers is the noise produced by aircraft during landing and takeoff. Over the years that followed, research was carried out at NASA aeronautics research centers, often in collaboration with academia and industry, addressing the problem. In 2013, a high-level milestone was established, described as a Technical Challenge, with the objective of demonstrating the feasibility of a low-boom supersonic airliner that could meet current airport noise regulations. The Technical Challenge was formally called "Low Noise Propulsion for Low Boom Aircraft", and was completed in late 2016. This paper reports the technical findings from this Technical Challenge, reaching back almost 10 years to review the technologies and tools that were developed along the way. It also discusses the final aircraft configuration and propulsion systems required for a supersonic civilian aircraft to meet noise regulations using the technologies available today. Finally, the paper documents the model-scale tests that validated the acoustic performance of the study aircraft.

  17. Transfer standard for the spectral density of relative intensity noise of optical fiber sources near 1550 nm

    International Nuclear Information System (INIS)

    Obarski, Gregory E.; Splett, Jolene D.

    2001-01-01

    We have developed a transfer standard for the spectral density of relative intensity noise (RIN) of optical fiber sources near 1550 nm. Amplified spontaneous emission (ASE) from an erbium-doped fiber amplifier (EDFA), when it is optically filtered over a narrow band (<5 nm), yields a stable RIN spectrum that is practically constant to several tens of gigahertz. The RIN is calculated from the power spectral density as measured with a calibrated optical spectrum analyzer. For a typical device it is -110 dB/Hz, with uncertainty ≤0.12 dB/Hz. The invariance of the RIN under attenuation yields a considerable dynamic range with respect to rf noise levels. Results are compared with those from a second method that uses a distributed-feedback laser (DFB) that has a Poisson-limited RIN. Application of each method to the same RIN measurement system yields frequency-dependent calibration functions that, when they are averaged, differ by ≤0.2 dB. [copyright] 2001 Optical Society of America

  18. Yoga versus non-standard care for schizophrenia.

    Science.gov (United States)

    Broderick, Julie; Crumlish, Niall; Waugh, Alice; Vancampfort, Davy

    2017-09-28

    Yoga is an ancient spiritual practice that originated in India and is currently accepted in the Western world as a form of relaxation and exercise. It has been of interest for people with schizophrenia as an alternative or adjunctive treatment. To systematically assess the effects of yoga versus non-standard care for people with schizophrenia. The Information Specialist of the Cochrane Schizophrenia Group searched their specialised Trials Register (latest 30 March 2017), which is based on regular searches of MEDLINE, PubMed, Embase, CINAHL, BIOSIS, AMED, PsycINFO, and registries of clinical trials. We searched the references of all included studies. There are no language, date, document type, or publication status limitations for inclusion of records in the register. All randomised controlled trials (RCTs) including people with schizophrenia and comparing yoga with non-standard care. We included trials that met our selection criteria and reported useable data. The review team independently selected studies, assessed quality, and extracted data. For binary outcomes, we calculated risk ratio (RR) and its 95% confidence interval (CI), on an intention-to-treat basis. For continuous data, we estimated the mean difference (MD) between groups and its 95% CI. We employed a fixed-effect models for analyses. We examined data for heterogeneity (I 2 technique), assessed risk of bias for included studies, and created a 'Summary of findings' table for seven main outcomes of interest using GRADE (Grading of Recommendations Assessment, Development and Evaluation). We were able to include six studies (586 participants). Non-standard care consisted solely of another type of exercise programme. All outcomes were short term (less than six months). There was a clear difference in the outcome leaving the study early (6 RCTs, n=586, RR 0.64 CI 0.49 to 0.83, medium quality evidence) in favour of the yoga group. There were no clear differences between groups for the remaining outcomes

  19. Force coordination in static manipulation tasks performed using standard and non-standard grasping techniques.

    Science.gov (United States)

    de Freitas, Paulo B; Jaric, Slobodan

    2009-04-01

    We evaluated coordination of the hand grip force (GF; normal component of the force acting at the hand-object contact area) and load force (LF; the tangential component) in a variety of grasping techniques and two LF directions. Thirteen participants exerted a continuous sinusoidal LF pattern against externally fixed handles applying both standard (i.e., using either the tips of the digits or the palms; the precision and palm grasps, respectively) and non-standard grasping techniques (using wrists and the dorsal finger areas; the wrist and fist grasp). We hypothesized (1) that the non-standard grasping techniques would provide deteriorated indices of force coordination when compared with the standard ones, and (2) that the nervous system would be able to adjust GF to the differences in friction coefficients of various skin areas used for grasping. However, most of the indices of force coordination remained similar across the tested grasping techniques, while the GF adjustments for the differences in friction coefficients (highest in the palm and the lowest in the fist and wrist grasp) provided inconclusive results. As hypothesized, GF relative to the skin friction was lowest in the precision grasp, but highest in the palm grasp. Therefore, we conclude that (1) the elaborate coordination of GF and LF consistently seen across the standard grasping techniques could be generalized to the non-standard ones, while (2) the ability to adjust GF using the same grasping technique to the differences in friction of various objects cannot be fully generalized to the GF adjustment when different grasps (i.e., hand segments) are used to manipulate the same object. Due to the importance of the studied phenomena for understanding both the functional and neural control aspects of manipulation, future studies should extend the current research to the transient and dynamic tasks, as well as to the general role of friction in our mechanical interactions with the environment.

  20. Noise Considerations in Resistance Bridges

    DEFF Research Database (Denmark)

    Diamond, Joseph M.

    1963-01-01

    A signal-to-noise analysis is made of the Wheatstone bridge, where the unknown and standard resistors may be at different temperatures, a situation which occurs in resistance thermometry. The limiting condition is assumed to be dissipation in the unknown resistor. It is shown that the ratio arms...... thermometry, where the noise in the unknown resistor will predominate strongly. An impedance step-up device (transformer or tuned circuit) is valuable in raising the bridge signal and noise level above the noise of the first amplifier tube. However, as the step-up ratio is increased, two counterfactors appear....... With certain assumptions about the noise and grid current of the first tube it is found that the equivalent temperature of a unity ratio (Mueller) bridge used for liquid helium measurements may be 400°K....

  1. An observational study of emergency department utilization among enrollees of Minnesota Health Care Programs: financial and non-financial barriers have different associations

    OpenAIRE

    Shippee, Nathan D; Shippee, Tetyana P; Hess, Erik P; Beebe, Timothy J

    2014-01-01

    Background Emergency department (ED) use is costly, and especially frequent among publicly insured populations in the US, who also disproportionately encounter financial (cost/coverage-related) and non-financial/practical barriers to care. The present study examines the distinct associations financial and non-financial barriers to care have with patterns of ED use among a publicly insured population. Methods This observational study uses linked administrative-survey data for enrollees of Minn...

  2. Qualitative criteria and thresholds for low noise asphalt mixture design

    Science.gov (United States)

    Vaitkus, A.; Andriejauskas, T.; Gražulytė, J.; Šernas, O.; Vorobjovas, V.; Kleizienė, R.

    2018-05-01

    Low noise asphalt pavements are cost efficient and cost effective alternative for road traffic noise mitigation comparing with noise barriers, façade insulation and other known noise mitigation measures. However, design of low noise asphalt mixtures strongly depends on climate and traffic peculiarities of different regions. Severe climate regions face problems related with short durability of low noise asphalt mixtures in terms of considerable negative impact of harsh climate conditions (frost-thaw, large temperature fluctuations, hydrological behaviour, etc.) and traffic (traffic loads, traffic volumes, studded tyres, etc.). Thus there is a need to find balance between mechanical and acoustical durability as well as to ensure adequate pavement skid resistance for road safety purposes. Paper presents analysis of the qualitative criteria and design parameters thresholds of low noise asphalt mixtures. Different asphalt mixture composition materials (grading, aggregate, binder, additives, etc.) and relevant asphalt layer properties (air void content, texture, evenness, degree of compaction, etc.) were investigated and assessed according their suitability for durable and effective low noise pavements. Paper concluded with the overview of requirements, qualitative criteria and thresholds for low noise asphalt mixture design for severe climate regions.

  3. Traffic noise affects forest bird species in a protected tropical forest

    Directory of Open Access Journals (Sweden)

    J. Edgardo Arévalo

    2011-06-01

    Full Text Available The construction of roads near protected forest areas alters ecosystem function by creating habitat fragmentation and through several direct and indirect negative effects such as increased pollution, animal mortality through collisions, disturbance caused by excessive noise and wind turbulence. Noise in particular may have strong negative effects on animal groups such as frogs and birds, that rely on sound for communication as it can negatively interfere with vocalizations used for territorial defense or courtship. Thus, birds are expected to be less abundant close to the road where noise levels are high. In this study, we examined the effects of road traffic noise levels on forest bird species in a protected tropical forest in Costa Rica. Data collection was conducted in a forest segment of the Carara National Park adjacent to the Coastal Highway. We carried out 120 ten minute bird surveys and measured road noise levels 192 times from the 19th to the 23rd of April and from the 21st to the 28th of November, 2008. To maximize bird detection for the species richness estimates we operated six 12m standard mist nets simultaneously with the surveys. The overall mist-netting effort was 240net/h. In addition, we estimated traffic volumes by tallying the number of vehicles passing by the edge of the park using 24 one hour counts throughout the study. We found that the relative abundance of birds and bird species richness decreased significantly with the increasing traffic noise in the dry and wet season. Noise decreased significantly and in a logarithmic way with distance from the road in both seasons. However, noise levels at any given distance were significantly higher in the dry compared to the wet season. Our results suggest that noise might be an important factor influencing road bird avoidance as measured by species richness and relative abundance. Since the protected forest in question is located in a national park subjected to tourist visitation

  4. TH-A-18C-07: Noise Suppression in Material Decomposition for Dual-Energy CT

    International Nuclear Information System (INIS)

    Dong, X; Petrongolo, M; Wang, T; Zhu, L

    2014-01-01

    Purpose: A general problem of dual-energy CT (DECT) is that the decomposition is sensitive to noise in the two sets of dual-energy projection data, resulting in severely degraded qualities of decomposed images. We have previously proposed an iterative denoising method for DECT. Using a linear decomposition function, the method does not gain the full benefits of DECT on beam-hardening correction. In this work, we expand the framework of our iterative method to include non-linear decomposition models for noise suppression in DECT. Methods: We first obtain decomposed projections, which are free of beam-hardening artifacts, using a lookup table pre-measured on a calibration phantom. First-pass material images with high noise are reconstructed from the decomposed projections using standard filter-backprojection reconstruction. Noise on the decomposed images is then suppressed by an iterative method, which is formulated in the form of least-square estimation with smoothness regularization. Based on the design principles of a best linear unbiased estimator, we include the inverse of the estimated variance-covariance matrix of the decomposed images as the penalty weight in the least-square term. Analytical formulae are derived to compute the variance-covariance matrix from the measured decomposition lookup table. Results: We have evaluated the proposed method via phantom studies. Using non-linear decomposition, our method effectively suppresses the streaking artifacts of beam-hardening and obtains more uniform images than our previous approach based on a linear model. The proposed method reduces the average noise standard deviation of two basis materials by one order of magnitude without sacrificing the spatial resolution. Conclusion: We propose a general framework of iterative denoising for material decomposition of DECT. Preliminary phantom studies have shown the proposed method improves the image uniformity and reduces noise level without resolution loss. In the future

  5. High level white noise generator

    International Nuclear Information System (INIS)

    Borkowski, C.J.; Blalock, T.V.

    1979-01-01

    A wide band, stable, random noise source with a high and well-defined output power spectral density is provided which may be used for accurate calibration of Johnson Noise Power Thermometers (JNPT) and other applications requiring a stable, wide band, well-defined noise power spectral density. The noise source is based on the fact that the open-circuit thermal noise voltage of a feedback resistor, connecting the output to the input of a special inverting amplifier, is available at the amplifier output from an equivalent low output impedance caused by the feedback mechanism. The noise power spectral density level at the noise source output is equivalent to the density of the open-circuit thermal noise or a 100 ohm resistor at a temperature of approximately 64,000 Kelvins. The noise source has an output power spectral density that is flat to within 0.1% (0.0043 db) in the frequency range of from 1 KHz to 100 KHz which brackets typical passbands of the signal-processing channels of JNPT's. Two embodiments, one of higher accuracy that is suitable for use as a standards instrument and another that is particularly adapted for ambient temperature operation, are illustrated in this application

  6. High level white noise generator

    Science.gov (United States)

    Borkowski, Casimer J.; Blalock, Theron V.

    1979-01-01

    A wide band, stable, random noise source with a high and well-defined output power spectral density is provided which may be used for accurate calibration of Johnson Noise Power Thermometers (JNPT) and other applications requiring a stable, wide band, well-defined noise power spectral density. The noise source is based on the fact that the open-circuit thermal noise voltage of a feedback resistor, connecting the output to the input of a special inverting amplifier, is available at the amplifier output from an equivalent low output impedance caused by the feedback mechanism. The noise power spectral density level at the noise source output is equivalent to the density of the open-circuit thermal noise or a 100 ohm resistor at a temperature of approximately 64,000 Kelvins. The noise source has an output power spectral density that is flat to within 0.1% (0.0043 db) in the frequency range of from 1 KHz to 100 KHz which brackets typical passbands of the signal-processing channels of JNPT's. Two embodiments, one of higher accuracy that is suitable for use as a standards instrument and another that is particularly adapted for ambient temperature operation, are illustrated in this application.

  7. Non-standard employment relationship and the gender dimension

    OpenAIRE

    Mihaela-Emilia Marica

    2015-01-01

    Besides influences economic, political and social on the standard form of individual employment contract, which led to a more flexible regulatory framework in the field of labor relations, an important factor that marked trend evolving contract atypical employment is the number of women who entered the labor market in recent decades. Because most strongly feminized form of employment non-standard employment relationship part-time, this article captures the issues most important about the r...

  8. 'Pipetron' beam dynamics with noise

    International Nuclear Information System (INIS)

    Shiltsev, V.D.

    1996-10-01

    Extra-large hadron collider, ''Pipetron'', at 100 TeV energy is currently under consideration. In this article we study the Pipetron transverse and longitudinal beam dynamics under influence of external noises. The major effects are growths of transverse and longitudinal emittances of the beam caused by noisy forces which vary over the revolution period or synchrotron oscillation period, respectively; and closed orbit distortions induced by slow drift of magnet positions. Based on analytical consideration of these phenomena, we estimate tolerable levels of these noises and compare them with available experimental data. Although it is concluded that transverse and, probably, longitudinal feedback systems are necessary for the emittance's preservation, and sophisticated beam-based orbit correction methods should be used at the Pipetron, we observe no unreasonable requirements which present and impenetrable barrier to the project

  9. Non-stationary least-squares complex decomposition for microseismic noise attenuation

    Science.gov (United States)

    Chen, Yangkang

    2018-06-01

    Microseismic data processing and imaging are crucial for subsurface real-time monitoring during hydraulic fracturing process. Unlike the active-source seismic events or large-scale earthquake events, the microseismic event is usually of very small magnitude, which makes its detection challenging. The biggest trouble of microseismic data is the low signal-to-noise ratio issue. Because of the small energy difference between effective microseismic signal and ambient noise, the effective signals are usually buried in strong random noise. I propose a useful microseismic denoising algorithm that is based on decomposing a microseismic trace into an ensemble of components using least-squares inversion. Based on the predictive property of useful microseismic event along the time direction, the random noise can be filtered out via least-squares fitting of multiple damping exponential components. The method is flexible and almost automated since the only parameter needed to be defined is a decomposition number. I use some synthetic and real data examples to demonstrate the potential of the algorithm in processing complicated microseismic data sets.

  10. ANALISIS SIFAT AKUSTIK PAGAR PEMBATAS SEBAGAI PEREDAM BISING KENDARAAN BERMOTOR: SALAH SATU ALTERNATIF PENGENDALI BISING DI KOTA DENPASAR (Analysis on The Acoustic Characteristic of Fence to Reduce Noise from Motorized Vehicles: One of The Alternatives

    Directory of Open Access Journals (Sweden)

    Putri Kusuma

    2015-01-01

    setting up barriers in a form of fence, especially that in Balinese traditional architecture. The research aims to study the effectiveness of different kinds of fence and to study the effects of these fences and the number of vehicles on the noise level produced. The research was conducted based on the (ISO R 1996 standard, namely the equivalence of noise level of n number of sample. It adopted a purposive sampling select the type of barrier, and focused on the following research objects: (1 type of fence, (2 distance of measurement from a noise source, and (3 type number of vehicles. The effectiveness of a barrier is expressed in the amount of noise reduction from a noise, either with or without barrier, and the coefficient of muting from each barrier. The tests to analyze the data are the correlation test to know the effectiveness of barrier and the regression test to know the kind of relationship between the type of vehicle and the noise level. The research found that a massive fence is the most effective noise reducer among different tyes of fence, with coefficient of 0.12. However, it offers less aesthetic element as it gives a impression of individualsm in addition to its structure that obstructs the eyes to see what is happening ourtside. A fence with gaps covered with vegetation is better both from the esthetic point of view and from physical function that is to reduce noise, with a coefficient of 0.09. The relation between the noise level and the number of vehicle can be identified by using a linear equation approach by putting the equivalence of the number of vehicle with that of motorcycle.

  11. Stochastic resonance in an asymmetric bistable system driven by multiplicative colored noise and additive white noise

    International Nuclear Information System (INIS)

    Zhou Bingchang; Xu Wei

    2008-01-01

    The phenomenon of stochastic resonance (SR) in a bistable system driven by multiplicative colored and additive white noises and a periodic rectangular signal with a constant component is studied by using the unified colored noise approximation and the theory of signal-to-noise (SNR) in the adiabatic limit. The analytic expression of the SNR is obtained for arbitrary signal amplitude without being restricted to small amplitudes. The SNR is a non-monotonic function of intensities of multiplicative colored and additive white noises and correlation time of multiplicative colored noise, so SR exhibits in the bistable system. The effects of potential asymmetry r and correlation time τ of multiplicative colored noise on SNR are opposite. Moreover, It is more sensitive to control SR through adjusting the additive white noise intensity D than adjusting the multiplicative colored noise intensity Q

  12. A Ratiometric Method for Johnson Noise Thermometry Using a Quantized Voltage Noise Source

    Science.gov (United States)

    Nam, S. W.; Benz, S. P.; Martinis, J. M.; Dresselhaus, P.; Tew, W. L.; White, D. R.

    2003-09-01

    Johnson Noise Thermometry (JNT) involves the measurement of the statistical variance of a fluctuating voltage across a resistor in thermal equilibrium. Modern digital techniques make it now possible to perform many functions required for JNT in highly efficient and predictable ways. We describe the operational characteristics of a prototype JNT system which uses digital signal processing for filtering, real-time spectral cross-correlation for noise power measurement, and a digitally synthesized Quantized Voltage Noise Source (QVNS) as an AC voltage reference. The QVNS emulates noise with a constant spectral density that is stable, programmable, and calculable in terms of known parameters using digital synthesis techniques. Changes in analog gain are accounted for by alternating the inputs between the Johnson noise sensor and the QVNS. The Johnson noise power at a known temperature is first balanced with a synthesized noise power from the QVNS. The process is then repeated by balancing the noise power from the same resistor at an unknown temperature. When the two noise power ratios are combined, a thermodynamic temperature is derived using the ratio of the two QVNS spectral densities. We present preliminary results where the ratio between the gallium triple point and the water triple point is used to demonstrate the accuracy of the measurement system with a standard uncertainty of 0.04 %.

  13. Unscented Kalman filtering in the additive noise case

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The unscented Kalman filter(UKF) has four implementations in the additive noise case,according to whether the state is augmented with noise vectors and whether a new set of sigma points is redrawn from the predicted state(which is so-called resampling) for the observation prediction.This paper concerns the differences of performances for those implementations,such as accuracy,adaptability,computational complexity,etc.The conditionally equivalent relationships between the augmented and non-augmented unscented transforms(UTs) are proved for several sampling strategies that are commonly used.Then,we find that the augmented and non-augmented UKFs have the same filter results with the additive measurement noise,but only have the same state predictions with the additive process noise.Resampling is not believed to be necessary in some researches.However,we find out that resampling can be helpful for an adaptive Kalman gain.This will improve the convergence and accuracy of the filter when the large scale state modeling bias or unknown maneuvers occur.Finally,some universal designing principles for a practical UKF are given as follows:1) for the additive observation noise case,it’s better to use the non-augmented UKF;2) for the additive process noise case,when the small state modeling bias or maneuvers are involved,the non-resampling algorithms with state whether augmented or not are candidates for filters;3) the resampling and non-augmented algorithm is the only choice while the large state modeling bias or maneuvers are latent.

  14. Semi-classical noise investigation for sub-40nm metal-oxide-semiconductor field-effect transistors

    International Nuclear Information System (INIS)

    Spathis, C.; Birbas, A.; Georgakopoulou, K.

    2015-01-01

    Device white noise levels in short channel Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) dictate the performance and reliability of high-frequency circuits ranging from high-speed microprocessors to Low-Noise Amplifiers (LNAs) and microwave circuits. Recent experimental noise measurements with very short devices demonstrate the existence of suppressed shot noise, contrary to the predictions of classical channel thermal noise models. In this work we show that, as the dimensions continue to shrink, shot noise has to be considered when the channel resistance becomes comparable to the barrier resistance at the source-channel junction. By adopting a semi-classical approach and taking retrospectively into account transport, short-channel and quantum effects, we investigate the partitioning between shot and thermal noise, and formulate a predictive model that describes the noise characteristics of modern devices

  15. Semi-classical noise investigation for sub-40nm metal-oxide-semiconductor field-effect transistors

    Energy Technology Data Exchange (ETDEWEB)

    Spathis, C., E-mail: cspathis@ece.upatras.gr; Birbas, A.; Georgakopoulou, K. [Department of Electrical and Computer Engineering, University of Patras, Patras 26500 (Greece)

    2015-08-15

    Device white noise levels in short channel Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) dictate the performance and reliability of high-frequency circuits ranging from high-speed microprocessors to Low-Noise Amplifiers (LNAs) and microwave circuits. Recent experimental noise measurements with very short devices demonstrate the existence of suppressed shot noise, contrary to the predictions of classical channel thermal noise models. In this work we show that, as the dimensions continue to shrink, shot noise has to be considered when the channel resistance becomes comparable to the barrier resistance at the source-channel junction. By adopting a semi-classical approach and taking retrospectively into account transport, short-channel and quantum effects, we investigate the partitioning between shot and thermal noise, and formulate a predictive model that describes the noise characteristics of modern devices.

  16. MIMO scheme performance and detection in epsilon noise

    OpenAIRE

    Stepanov, Sander

    2006-01-01

    New approach for analysis and decoding MIMO signaling is developed for usual model of nongaussion noise consists of background and impulsive noise named epsilon - noise. It is shown that non-gaussion noise performance significantly worse than gaussion ones. Stimulation results strengthen out theory. Robust in statistical sense detection rule is suggested for such kind of noise features much best robust detector performance than detector designed for Gaussian noise in impulsive environment and...

  17. Programmable, very low noise current source

    Science.gov (United States)

    Scandurra, G.; Cannatà, G.; Giusi, G.; Ciofi, C.

    2014-12-01

    We propose a new approach for the realization of very low noise programmable current sources mainly intended for application in the field of low frequency noise measurements. The design is based on a low noise Junction Field Effect Transistor (JFET) acting as a high impedance current source and programmability is obtained by resorting to a low noise, programmable floating voltage source that allows to set the sourced current at the desired value. The floating voltage source is obtained by exploiting the properties of a standard photovoltaic MOSFET driver. Proper filtering and a control network employing super-capacitors allow to reduce the low frequency output noise to that due to the low noise JFET down to frequencies as low as 100 mHz while allowing, at the same time, to set the desired current by means of a standard DA converter with an accuracy better than 1%. A prototype of the system capable of supplying currents from a few hundreds of μA up to a few mA demonstrates the effectiveness of the approach we propose. When delivering a DC current of about 2 mA, the power spectral density of the current fluctuations at the output is found to be less than 25 pA/√Hz at 100 mHz and less than 6 pA/√Hz for f > 1 Hz, resulting in an RMS noise in the bandwidth from 0.1 to 10 Hz of less than 14 pA.

  18. Reduction of external noise of mobile energy facilities by using active noise control system in muffler

    Science.gov (United States)

    Polivaev, O. I.; Kuznetsov, A. N.; Larionov, A. N.; Beliansky, R. G.

    2018-03-01

    The paper describes a method for the reducing emission of low-frequency noise of modern automotive vehicles into the environment. The importance of reducing the external noise of modern mobile energy facilities made in Russia is substantiated. Standard methods for controlling external noise in technology are of low efficiency when low-frequency sound waves are reduced. In this case, it is in the low-frequency zone of the sound range that the main power of the noise emitted by the machinery lies. The most effective way to reduce such sound waves is to use active noise control systems. A design of a muffler using a similar system is presented. This muffler allowed one to reduce the emission of increased noise levels into the environment by 7-11 dB and to increase acoustic comfort at the operator's workplace by 3-5 dB.

  19. Non-reciprocal Interspecies Hybridization Barriers in the Capsella Genus Are Established in the Endosperm.

    Directory of Open Access Journals (Sweden)

    Carolin A Rebernig

    2015-06-01

    Full Text Available The transition to selfing in Capsella rubella accompanies its recent divergence from the ancestral outcrossing C. grandiflora species about 100,000 years ago. Whether the change in mating system was accompanied by the evolution of additional reproductive barriers that enforced species divergence remained unknown. Here, we show that C. rubella and C. grandiflora are reproductively separated by an endosperm-based, non-reciprocal postzygotic hybridization barrier. While hybridizations of C. rubella maternal plants with C. grandiflora pollen donors resulted in complete seed abortion caused by endosperm cellularization failure, the reciprocal hybridization resulted in the formation of small seeds with precociously cellularized endosperm. Strikingly, the transcriptomic response of both hybridizations mimicked respectively the response of paternal and maternal excess hybridizations in Arabidopsis thaliana, suggesting unbalanced genome strength causes hybridization failure in both species. These results provide strong support for the theory that crosses between plants of different mating systems will be unbalanced, with the outcrosser behaving like a plant of increased ploidy, evoking a response that resembles an interploidy-type seed failure. Seed incompatilibity of C. rubella pollinated by C. grandiflora followed the Bateson-Dobzhansky-Muller model, involving negative genetic interaction of multiple paternal C. grandiflora loci with at least one maternal C. rubella locus. Given that both species only recently diverged, our data suggest that a fast evolving mechanism underlies the post-zygotic hybridization barrier(s separating both species.

  20. An examination of the parametric properties of four noise sensitivity measures

    DEFF Research Database (Denmark)

    van Kamp, Irene; Ellermeier, Wolfgang; Lopez-Barrio, Isabel

    2006-01-01

    Noise sensitivity (NS) is a personality trait with a strong influence on reactions to noise. Studies of reaction should include a standard measure of NS that is founded on a theoretically justified definition of NS, and examination of existing NS measures' parametric properties (internal consiste......, demographics and lifestyle). A standard NS measure should demonstrate high reliability, and should predict responses to noise. Discussion is welcomed and will focus on validation strategies and optimizing the study design.......Noise sensitivity (NS) is a personality trait with a strong influence on reactions to noise. Studies of reaction should include a standard measure of NS that is founded on a theoretically justified definition of NS, and examination of existing NS measures' parametric properties (internal...... consistency; stability; convergent and predictive validity). At each of 6 laboratory centres (Aalborg; London; Sydney; Dortmund; Madrid, Amsterdam), participants will complete four NS measures on each of two occasions. In one occasion, participants will complete a task while exposed to recorded aircraft noise...

  1. High-order noise analysis for low dose iterative image reconstruction methods: ASIR, IRIS, and MBAI

    Science.gov (United States)

    Do, Synho; Singh, Sarabjeet; Kalra, Mannudeep K.; Karl, W. Clem; Brady, Thomas J.; Pien, Homer

    2011-03-01

    Iterative reconstruction techniques (IRTs) has been shown to suppress noise significantly in low dose CT imaging. However, medical doctors hesitate to accept this new technology because visual impression of IRT images are different from full-dose filtered back-projection (FBP) images. Most common noise measurements such as the mean and standard deviation of homogeneous region in the image that do not provide sufficient characterization of noise statistics when probability density function becomes non-Gaussian. In this study, we measure L-moments of intensity values of images acquired at 10% of normal dose and reconstructed by IRT methods of two state-of-art clinical scanners (i.e., GE HDCT and Siemens DSCT flash) by keeping dosage level identical to each other. The high- and low-dose scans (i.e., 10% of high dose) were acquired from each scanner and L-moments of noise patches were calculated for the comparison.

  2. Atomistic modeling of the structural components of the blood-brain barrier

    Science.gov (United States)

    Glukhova, O. E.; Grishina, O. A.; Slepchenkov, M. M.

    2015-03-01

    Blood-brain barrier, which is a barrage system between the brain and blood vessels, plays a key role in the "isolation" of the brain of unnecessary information, and reduce the "noise" in the interneuron communication. It is known that the barrier function of the BBB strictly depends on the initial state of the organism and changes significantly with age and, especially in developing the "vascular accidents". Disclosure mechanisms of regulation of the barrier function will develop new ways to deliver neurotrophic drugs to the brain in the newborn. The aim of this work is the construction of atomistic models of structural components of the blood-brain barrier to reveal the mechanisms of regulation of the barrier function.

  3. Market barriers to welfare product innovations

    NARCIS (Netherlands)

    Binnekamp, M.H.A.; Ingenbleek, P.T.M.

    2006-01-01

    New products that are based on higher animal welfare standards encounter several barriers on the road to market acceptance. The authors focus on the Dutch poultry sector and distinguish between retailer and consumer barriers. Retailer barriers include the powerful position of retailers, the price

  4. Electrochemical noise from corroding carbon steel and aluminium

    International Nuclear Information System (INIS)

    Singh, P.R.; Gaonkar, K.B.; De, P.K.; Banerjee, S.

    1997-05-01

    Electrochemical noise measurements were conducted on carbon steel and aluminium in sodium chloride solutions. Noise parameters like standard deviation of potential and current, noise resistance, pitting index, noise power were studied for the purpose of measuring corrosion rate. These parameters compared well with the corrosion rate. Pitting index was not very reliable. Current noise was more close to the corrosion rates. General corrosion gave rise to white noise type of power spectrum while flicker noise type of spectrum was obtained from pitting attack. Sodium nitrite is shown to inhibit the corrosion of carbon steel. Aluminium corrodes in the early period of exposure and passivates during long exposure

  5. Impact of environmental noise on growth and neuropsychological development of newborn rats.

    Science.gov (United States)

    Zheng, Yanyan; Meng, Meng; Zhao, Congmin; Liao, Wei; Zhang, Yuping; Wang, Liyan; Wen, Enyi

    2014-05-01

    We aimed to investigate the effects of environmental noise exposure on the growth and neuropsychological development in neonatal rats. Twenty-four postnatal 7-day-old Sprague-Dawley rats were randomly assigned into control, high-noise and reduced noise groups. The rats in the high-noise group were exposed to 90 dB white noise, and those in the control group were grown under standard condition, while those in the reduced noise group were exposed to standard condition with sound-absorbing cotton. Ten, 15, and 20 days post noise exposure, both the body weight and length of the rats in high-noise group were lower than those in the control and reduced noise groups, respectively. The secretion of growth hormone was significantly decreased in the rats exposed to high noise environment, compared to those exposed to standard condition and reduced noise. More interestingly, the swimming distance was apparently increased and the swimming speed was significantly decreased in high-noise group compared with those in control and reduced noise groups. Importantly, the mRNA and protein levels of SYP in the rats hippocampus were significantly decreased in high-noise group compare with those in control and reduced noise groups. Similarly, the positive expression of SYP in the CA1 region of hippocampus was also significantly decreased in the high noise group rats. In conclusion, our results demonstrated that high noise exposure could decrease the production of growth hormone and SYP in neonatal rats, which may retard the growth of weight and length and the capability of learning and memory. Copyright © 2014 Wiley Periodicals, Inc.

  6. Identifying non-technical skills and barriers for improvement of teamwork in cardiac arrest teams

    DEFF Research Database (Denmark)

    Andersen, P.O.; Jensen, Michael Kammer; Lippert, A.

    2010-01-01

    Background: The application of non-technical skills (NTSs) in health care has previously been described in other health-care educational programmes. NTSs are behavioural principles such as leadership, task distribution and communication. The aim of this study was to identify NTSs suitable...... for improving team performance in multi-professional cardiac arrest teams, and to describe barriers to the use and implementation of such NTSs by using a qualitative method. Methods: Individual semi-structured interviews were conducted with 11 Danish Advanced Life Support instructors during the period April...... 2006 to November 2006. Interviews were focussed on barriers and recommendations for teamwork in the cardiac arrest team, optimal policy for improvement of resuscitation training and clinical practice, use of cognitive aids and adoption of European Resuscitation Council (ERC) Guidelines 2005. Interviews...

  7. Accurate estimation of camera shot noise in the real-time

    Science.gov (United States)

    Cheremkhin, Pavel A.; Evtikhiev, Nikolay N.; Krasnov, Vitaly V.; Rodin, Vladislav G.; Starikov, Rostislav S.

    2017-10-01

    Nowadays digital cameras are essential parts of various technological processes and daily tasks. They are widely used in optics and photonics, astronomy, biology and other various fields of science and technology such as control systems and video-surveillance monitoring. One of the main information limitations of photo- and videocameras are noises of photosensor pixels. Camera's photosensor noise can be divided into random and pattern components. Temporal noise includes random noise component while spatial noise includes pattern noise component. Temporal noise can be divided into signal-dependent shot noise and signal-nondependent dark temporal noise. For measurement of camera noise characteristics, the most widely used methods are standards (for example, EMVA Standard 1288). It allows precise shot and dark temporal noise measurement but difficult in implementation and time-consuming. Earlier we proposed method for measurement of temporal noise of photo- and videocameras. It is based on the automatic segmentation of nonuniform targets (ASNT). Only two frames are sufficient for noise measurement with the modified method. In this paper, we registered frames and estimated shot and dark temporal noises of cameras consistently in the real-time. The modified ASNT method is used. Estimation was performed for the cameras: consumer photocamera Canon EOS 400D (CMOS, 10.1 MP, 12 bit ADC), scientific camera MegaPlus II ES11000 (CCD, 10.7 MP, 12 bit ADC), industrial camera PixeLink PL-B781F (CMOS, 6.6 MP, 10 bit ADC) and video-surveillance camera Watec LCL-902C (CCD, 0.47 MP, external 8 bit ADC). Experimental dependencies of temporal noise on signal value are in good agreement with fitted curves based on a Poisson distribution excluding areas near saturation. Time of registering and processing of frames used for temporal noise estimation was measured. Using standard computer, frames were registered and processed during a fraction of second to several seconds only. Also the

  8. Characterizing transient noise in the LIGO detectors

    Science.gov (United States)

    Nuttall, L. K.

    2018-05-01

    Data from the LIGO detectors typically contain many non-Gaussian noise transients which arise due to instrumental and environmental conditions. These non-Gaussian transients can be an issue for the modelled and unmodelled transient gravitational-wave searches, as they can mask or mimic a true signal. Data quality can change quite rapidly, making it imperative to track and find new sources of transient noise so that data are minimally contaminated. Several examples of transient noise and the tools used to track them are presented. These instances serve to highlight the diverse range of noise sources present at the LIGO detectors during their second observing run. This article is part of a discussion meeting issue `The promises of gravitational-wave astronomy'.

  9. Barriers to and Methods of Help Seeking for Domestic Violence Victimization: A Comparison of Hispanic and Non-Hispanic White Women Residing in the United States.

    Science.gov (United States)

    Bridges, Ana J; Karlsson, Marie E; Jackson, Jennifer C; Andrews, Arthur R; Villalobos, Bianca T

    2018-02-01

    This study examined strategies Hispanic and non-Hispanic White victims of domestic violence use to manage violence and leave their relationships. Participants ( N = 76, 41% Hispanic) completed self-report questionnaires and a semistructured interview with a language-congruent research assistant. Hispanics reported child care needs and fears of social embarrassment as barriers to leaving, while non-Hispanic Whites reported fewer social supports as a barrier. Hispanics were more likely to use legal resources for help, while non-Hispanic Whites used more informal resources. Recognizing unique barriers to leaving abusive relationships and accessing help can guide service providers and others to target vulnerable populations more effectively.

  10. Barriers to and facilitators of independent non-medical prescribing in clinical practice: a mixed-methods systematic review

    Directory of Open Access Journals (Sweden)

    Timothy Noblet

    2017-10-01

    Registration: PROSPERO CRD42015017212. [Noblet T, Marriott J, Graham-Clarke E, Rushton A (2017 Barriers to and facilitators of independent non-medical prescribing in clinical practice: a mixed-methods systematic review. Journal of Physiotherapy 63: 221–234

  11. Effect of non-magnetic intermediate layer on film structure, magnetic properties, and noise characteristics of FeCSi soft magnetic multilayers

    International Nuclear Information System (INIS)

    Kawano, Hiroyasu; Morikawa, Takeshi; Matsumoto, Koji; Shono, Keiji

    2004-01-01

    The film structures, magnetic properties, and noise characteristics of soft magnetic multilayers with alternately stacked FeCSi soft magnetic layers and non-magnetic intermediate layers were investigated. The FeCSi layers in an as-deposited multilayer with C or Ta intermediate layers had the same nano-sized fine crystalline grains and low media noise as an as-deposited FeCSi monolayer. Amorphous C intermediate layers suppressed the amplitude of spike noise especially well. In contrast, FeCSi layers in an as-deposited multilayer with Cr or Ti intermediate layers were composed of coarse crystalline grains, which increased the media noise. The crystallographic match at the interface between the layers in a multilayer could explain these phenomena. The similarity of the atomic arrangement at the interface between layers and the crystallographic match of less than a few percent for the distance between atoms crystallized FeCSi layers with nano-sized fine crystalline grains into ones with coarse crystalline grains during deposition

  12. Detecting nonlinearity in time series driven by non-Gaussian noise: the case of river flows

    Directory of Open Access Journals (Sweden)

    F. Laio

    2004-01-01

    Full Text Available Several methods exist for the detection of nonlinearity in univariate time series. In the present work we consider riverflow time series to infer the dynamical characteristics of the rainfall-runoff transformation. It is shown that the non-Gaussian nature of the driving force (rainfall can distort the results of such methods, in particular when surrogate data techniques are used. Deterministic versus stochastic (DVS plots, conditionally applied to the decay phases of the time series, are instead proved to be a suitable tool to detect nonlinearity in processes driven by non-Gaussian (Poissonian noise. An application to daily discharges from three Italian rivers provides important clues to the presence of nonlinearity in the rainfall-runoff transformation.

  13. Relic abundance of WIMPs in non-standard cosmological scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Yimingniyazi, W.

    2007-08-06

    In this thesis we study the relic density n{sub {chi}} of non--relativistic long--lived or stable particles {chi} in various non--standard cosmological scenarios. First, we discuss the relic density in the non--standard cosmological scenario in which the temperature is too low for the particles {chi} to achieve full chemical equilibrium. We also investigated the case where {chi} particles are non--thermally produced from the decay of heavier particles in addition to the usual thermal production. In low temperature scenario, we calculate the relic abundance starting from arbitrary initial temperatures T{sub 0} of the radiation--dominated epoch and derive approximate solutions for the temperature dependence of the relic density which can accurately reproduces numerical results when full thermal equilibrium is not achieved. If full equilibrium is reached, our ansatz no longer reproduces the correct temperature dependence of the {chi} number density. However, we can contrive a semi-analytic formula which gives the correct final relic density, to an accuracy of about 3% or better, for all cross sections and initial temperatures. We also derive the lower bound on the initial temperature T{sub 0}, assuming that the relic particle accounts for the dark matter energy density in the universe. The observed cold dark matter abundance constrains the initial temperature T{sub 0} {>=}m{sub {chi}}/23, where m{sub {chi}} is the mass of {chi}. Second, we discuss the {chi} density in the scenario where the the Hubble parameter is modified. Even in this case, an approximate formula similar to the standard one is found to be capable of predicting the final relic abundance correctly. Choosing the {chi} annihilation cross section such that the observed cold dark matter abundance is reproduced in standard cosmology, we constrain possible modifications of the expansion rate at T {proportional_to}m{sub {chi}}/20, well before Big Bang Nucleosynthesis. (orig.)

  14. Relic abundance of WIMPs in non-standard cosmological scenarios

    International Nuclear Information System (INIS)

    Yimingniyazi, W.

    2007-01-01

    In this thesis we study the relic density n χ of non--relativistic long--lived or stable particles χ in various non--standard cosmological scenarios. First, we discuss the relic density in the non--standard cosmological scenario in which the temperature is too low for the particles χ to achieve full chemical equilibrium. We also investigated the case where χ particles are non--thermally produced from the decay of heavier particles in addition to the usual thermal production. In low temperature scenario, we calculate the relic abundance starting from arbitrary initial temperatures T 0 of the radiation--dominated epoch and derive approximate solutions for the temperature dependence of the relic density which can accurately reproduces numerical results when full thermal equilibrium is not achieved. If full equilibrium is reached, our ansatz no longer reproduces the correct temperature dependence of the χ number density. However, we can contrive a semi-analytic formula which gives the correct final relic density, to an accuracy of about 3% or better, for all cross sections and initial temperatures. We also derive the lower bound on the initial temperature T 0 , assuming that the relic particle accounts for the dark matter energy density in the universe. The observed cold dark matter abundance constrains the initial temperature T 0 ≥m χ /23, where m χ is the mass of χ. Second, we discuss the χ density in the scenario where the the Hubble parameter is modified. Even in this case, an approximate formula similar to the standard one is found to be capable of predicting the final relic abundance correctly. Choosing the χ annihilation cross section such that the observed cold dark matter abundance is reproduced in standard cosmology, we constrain possible modifications of the expansion rate at T ∝m χ /20, well before Big Bang Nucleosynthesis. (orig.)

  15. Monitoring the mechanical vibration of in-core detector tubes and fuel channels via ICFD noise analysis

    International Nuclear Information System (INIS)

    Glockler, O.; Cooke, D.F.; Czuppon, G.J.; Kapoor, K.K.

    2000-01-01

    Vibrations of core internals are regularly monitored in the CANDU nuclear generating stations of Ontario Power Generation (OPG) via the noise analysis of in-core flux detectors (ICFDs). Voltage signals of standard station instrumentation are recorded by portable multi-channel high-speed high-resolution data acquisition systems, then statistical parameters are derived from the multi-channel time series measurements. Reactor noise analysis is a non-intrusive statistical technique regularly used in system surveillance, diagnostics and in actual operational I and C problems. It utilizes the dynamic information carried by the small fluctuations (noise) of station signals measured around their mean values during steady-state operation. The present paper discusses specific results related to the flow-induced mechanical vibrations of detector tubes and fuel channels. (author)

  16. Statistical Angles on the Lattice QCD Signal-to-Noise Problem

    Science.gov (United States)

    Wagman, Michael L.

    The theory of quantum chromodynamics (QCD) encodes the strong interactions that bind quarks and gluons into nucleons and that bind nucleons into nuclei. Predictive control of QCD would allow nuclear structure and reactions as well as properties of supernovae and neutron stars to be theoretically studied from first principles. Lattice QCD (LQCD) can represent generic QCD predictions in terms of well-defined path integrals, but the sign and signal-to-noise problems have obstructed LQCD calculations of large nuclei and nuclear matter in practice. This thesis presents a statistical study of LQCD correlation functions, with a particular focus on characterizing the structure of the noise associated with quantum fluctuations. The signal-to-noise problem in baryon correlation functions is demonstrated to arise from a sign problem associated with Monte Carlo sampling of complex correlation functions. Properties of circular statistics are used to understand the emergence of a large time noise region where standard energy measurements are unreliable. Power-law tails associated with stable distributions and Levy flights are found to play a central role in the time evolution of baryon correlation functions. Building on these observations, a new statistical analysis technique called phase reweighting is introduced that allow energy levels to be extracted from large-time correlation functions with time-independent signal-to-noise ratios. Phase reweighting effectively includes dynamical refinement of source magnitudes but introduces a bias associated with the phase. This bias can be removed by performing an extrapolation, but at the expense of re-introducing a signal-to-noise problem. Lattice QCD calculations of the ρ+ and nucleon masses and of the ΞΞ(1S0) binding energy show consistency between standard results obtained using smaller-time correlation functions and phase-reweighted results using large-time correlation functions inaccessible to standard statistical analysis

  17. Non-standard neutrino interactions in the mu–tau sector

    Directory of Open Access Journals (Sweden)

    Irina Mocioiu

    2015-04-01

    Full Text Available We discuss neutrino mass hierarchy implications arising from the effects of non-standard neutrino interactions on muon rates in high statistics atmospheric neutrino oscillation experiments like IceCube DeepCore. We concentrate on the mu–tau sector, which is presently the least constrained. It is shown that the magnitude of the effects depends strongly on the sign of the ϵμτ parameter describing this non-standard interaction. A simple analytic model is used to understand the parameter space where differences between the two signs are maximized. We discuss how this effect is partially degenerate with changing the neutrino mass hierarchy, as well as how this degeneracy could be lifted.

  18. Local noise in a diffusive conductor

    Science.gov (United States)

    Tikhonov, E. S.; Shovkun, D. V.; Ercolani, D.; Rossella, F.; Rocci, M.; Sorba, L.; Roddaro, S.; Khrapai, V. S.

    2016-07-01

    The control and measurement of local non-equilibrium configurations is of utmost importance in applications on energy harvesting, thermoelectrics and heat management in nano-electronics. This challenging task can be achieved with the help of various local probes, prominent examples including superconducting or quantum dot based tunnel junctions, classical and quantum resistors, and Raman thermography. Beyond time-averaged properties, valuable information can also be gained from spontaneous fluctuations of current (noise). From these perspective, however, a fundamental constraint is set by current conservation, which makes noise a characteristic of the whole conductor, rather than some part of it. Here we demonstrate how to remove this obstacle and pick up a local noise temperature of a current biased diffusive conductor with the help of a miniature noise probe. This approach is virtually noninvasive for the electronic energy distributions and extends primary local measurements towards strongly non-equilibrium regimes.

  19. Exploring conservative islands using correlated and uncorrelated noise

    Science.gov (United States)

    da Silva, Rafael M.; Manchein, Cesar; Beims, Marcus W.

    2018-02-01

    In this work, noise is used to analyze the penetration of regular islands in conservative dynamical systems. For this purpose we use the standard map choosing nonlinearity parameters for which a mixed phase space is present. The random variable which simulates noise assumes three distributions, namely equally distributed, normal or Gaussian, and power law (obtained from the same standard map but for other parameters). To investigate the penetration process and explore distinct dynamical behaviors which may occur, we use recurrence time statistics (RTS), Lyapunov exponents and the occupation rate of the phase space. Our main findings are as follows: (i) the standard deviations of the distributions are the most relevant quantity to induce the penetration; (ii) the penetration of islands induce power-law decays in the RTS as a consequence of enhanced trapping; (iii) for the power-law correlated noise an algebraic decay of the RTS is observed, even though sticky motion is absent; and (iv) although strong noise intensities induce an ergodic-like behavior with exponential decays of RTS, the largest Lyapunov exponent is reminiscent of the regular islands.

  20. Non-Markovian stochastic Schroedinger equations: Generalization to real-valued noise using quantum-measurement theory

    International Nuclear Information System (INIS)

    Gambetta, Jay; Wiseman, H.M.

    2002-01-01

    Do stochastic Schroedinger equations, also known as unravelings, have a physical interpretation? In the Markovian limit, where the system on average obeys a master equation, the answer is yes. Markovian stochastic Schroedinger equations generate quantum trajectories for the system state conditioned on continuously monitoring the bath. For a given master equation, there are many different unravelings, corresponding to different sorts of measurement on the bath. In this paper we address the non-Markovian case, and in particular the sort of stochastic Schroedinger equation introduced by Strunz, Diosi, and Gisin [Phys. Rev. Lett. 82, 1801 (1999)]. Using a quantum-measurement theory approach, we rederive their unraveling that involves complex-valued Gaussian noise. We also derive an unraveling involving real-valued Gaussian noise. We show that in the Markovian limit, these two unravelings correspond to heterodyne and homodyne detection, respectively. Although we use quantum-measurement theory to define these unravelings, we conclude that the stochastic evolution of the system state is not a true quantum trajectory, as the identity of the state through time is a fiction

  1. Training Methods for Image Noise Level Estimation on Wavelet Components

    Directory of Open Access Journals (Sweden)

    A. De Stefano

    2004-12-01

    Full Text Available The estimation of the standard deviation of noise contaminating an image is a fundamental step in wavelet-based noise reduction techniques. The method widely used is based on the mean absolute deviation (MAD. This model-based method assumes specific characteristics of the noise-contaminated image component. Three novel and alternative methods for estimating the noise standard deviation are proposed in this work and compared with the MAD method. Two of these methods rely on a preliminary training stage in order to extract parameters which are then used in the application stage. The sets used for training and testing, 13 and 5 images, respectively, are fully disjoint. The third method assumes specific statistical distributions for image and noise components. Results showed the prevalence of the training-based methods for the images and the range of noise levels considered.

  2. Image denoising based on noise detection

    Science.gov (United States)

    Jiang, Yuanxiang; Yuan, Rui; Sun, Yuqiu; Tian, Jinwen

    2018-03-01

    Because of the noise points in the images, any operation of denoising would change the original information of non-noise pixel. A noise detection algorithm based on fractional calculus was proposed to denoise in this paper. Convolution of the image was made to gain direction gradient masks firstly. Then, the mean gray was calculated to obtain the gradient detection maps. Logical product was made to acquire noise position image next. Comparisons in the visual effect and evaluation parameters after processing, the results of experiment showed that the denoising algorithms based on noise were better than that of traditional methods in both subjective and objective aspects.

  3. Restoration of Static JPEG Images and RGB Video Frames by Means of Nonlinear Filtering in Conditions of Gaussian and Non-Gaussian Noise

    Science.gov (United States)

    Sokolov, R. I.; Abdullin, R. R.

    2017-11-01

    The use of nonlinear Markov process filtering makes it possible to restore both video stream frames and static photos at the stage of preprocessing. The present paper reflects the results of research in comparison of these types image filtering quality by means of special algorithm when Gaussian or non-Gaussian noises acting. Examples of filter operation at different values of signal-to-noise ratio are presented. A comparative analysis has been performed, and the best filtered kind of noise has been defined. It has been shown the quality of developed algorithm is much better than quality of adaptive one for RGB signal filtering at the same a priori information about the signal. Also, an advantage over median filter takes a place when both fluctuation and pulse noise filtering.

  4. On signal design by the R sub 0 criterion for non-white Gaussian noise channels

    Science.gov (United States)

    Bordelon, D. L.

    1976-01-01

    The use of the R sub 0 criterion for modulation system design is investigated for channels with non-white Gaussian noise. A signal space representation of the waveform channel is developed, and the cut-off rate R sub 0 for vector channels with additive nonwhite Gaussian noise and unquantized demodulation is derived. When the signal unput to the channel is a continuous random vector, maximization of R sub 0 with constrained average signal energy leads to a water-filling interpretation of optimal energy distribution in signal space. The necessary condition for a finite signal set to maximize R sub 0 with constrained energy and an equally likely probability assignment of signal vectors is presented, and an algorithm is outlined for numerically computing the optimum signal set. A necessary condition on a constrained energy, finite signal set is found which maximizes a Taylor series approximation of R sub 0. This signal set is compared with the finite signal set which has the water-filling average energy distribution.

  5. Implementation of a Non-Metallic Barrier in an Electric Motor

    Science.gov (United States)

    M'Sadoques, George A. (Inventor); Carra, Michael R. (Inventor); Beringer, Durwood M. (Inventor)

    2013-01-01

    A motor for use in a volatile environment includes a rotor exposed to the volatile environment, electronics for rotating the rotor, an impervious ceramic barrier separating the electronics and the rotor, and a flexible seal for preventing the volatile environment from contacting the electronics and for minimizing vibratory and twisting loads upon the barrier to minimize damage to the barrier.

  6. CONDITIONS FOR OVERCOMING COMMUNICATION-LANGUAGE BARRIERS IN THE SYSTEM OF NON-LINGUISTIC HIGHER EDUCATION

    Directory of Open Access Journals (Sweden)

    Lidiya Olegovna Polyakova

    2016-01-01

    Results. Results of our scientific work are such conditions should be implemented based on the principle of «vertical integration», covering the social levels of the customer of higher education (economic sector, national systems of higher education, the University, the faculty, the chair. Practical implications. Presents a set of tools that is effective in solving problems of communication-language barriers of future specialists of non-linguistic profile.

  7. Transfer standard for the spectral density of relative intensity noise of optical fiber sources near 1550 nm

    Energy Technology Data Exchange (ETDEWEB)

    Obarski, Gregory E.; Splett, Jolene D.

    2001-06-01

    We have developed a transfer standard for the spectral density of relative intensity noise (RIN) of optical fiber sources near 1550 nm. Amplified spontaneous emission (ASE) from an erbium-doped fiber amplifier (EDFA), when it is optically filtered over a narrow band ({lt}5 nm), yields a stable RIN spectrum that is practically constant to several tens of gigahertz. The RIN is calculated from the power spectral density as measured with a calibrated optical spectrum analyzer. For a typical device it is {minus}110 dB/Hz, with uncertainty {le}0.12 dB/Hz. The invariance of the RIN under attenuation yields a considerable dynamic range with respect to rf noise levels. Results are compared with those from a second method that uses a distributed-feedback laser (DFB) that has a Poisson-limited RIN. Application of each method to the same RIN measurement system yields frequency-dependent calibration functions that, when they are averaged, differ by {le}0.2 dB. {copyright} 2001 Optical Society of America

  8. 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.

  9. CHANGES AND MODIFICATIONS OF THE TROUSERS PATENS FOR NON-STANDARD FIGURES

    Directory of Open Access Journals (Sweden)

    SUDACEVSCHI SVETLANA

    2015-12-01

    Full Text Available Among the problems faced by the constructors of clothing goods are the non-standard figures of the human body. The present article examines the possibilities of modifying the curve of women’s trousers. The author proposes methods of chang­ing the basic drawing of the women’s trousers for figures with non-standard figures and to use these methods in the process of training in specialized educational institutions.

  10. Mentoring overseas nurses: barriers to effective and non-discriminatory mentoring practices.

    Science.gov (United States)

    Allan, Helen

    2010-09-01

    In this article it is argued that there are barriers to effective and non-discriminatory practice when mentoring overseas nurses within the National Health Service (NHS) and the care home sector. These include a lack of awareness about how cultural differences affect mentoring and learning for overseas nurses during their period of supervised practice prior to registration with the UK Nursing and Midwifery Council. These barriers may demonstrate a lack of effective teaching of ethical practice in the context of cultural diversity in health care. This argument is supported by empirical data from a national study. Interviews were undertaken with 93 overseas nurses and 24 national and 13 local managers and mentors from six research sites involving UK health care employers in the NHS and independent sectors in different regions of the UK. The data collected showed that overseas nurses are discriminated against in their learning by poor mentoring practices; equally, from these data, it appears that mentors are ill-equipped by existing mentor preparation programmes to mentor overseas-trained nurses from culturally diverse backgrounds. Recommendations are made for improving mentoring programmes to address mentors' ability to facilitate learning in a culturally diverse workplace and thereby improve overseas nurses' experiences of their supervised practice.

  11. Evaluation of internal noise methods for Hotelling observer models

    International Nuclear Information System (INIS)

    Zhang Yani; Pham, Binh T.; Eckstein, Miguel P.

    2007-01-01

    The inclusion of internal noise in model observers is a common method to allow for quantitative comparisons between human and model observer performance in visual detection tasks. In this article, we studied two different strategies for inserting internal noise into Hotelling model observers. In the first strategy, internal noise was added to the output of individual channels: (a) Independent nonuniform channel noise, (b) independent uniform channel noise. In the second strategy, internal noise was added to the decision variable arising from the combination of channel responses. The standard deviation of the zero mean internal noise was either constant or proportional to: (a) the decision variable's standard deviation due to the external noise, (b) the decision variable's variance caused by the external noise, (c) the decision variable magnitude on a trial to trial basis. We tested three model observers: square window Hotelling observer (HO), channelized Hotelling observer (CHO), and Laguerre-Gauss Hotelling observer (LGHO) using a four alternative forced choice (4AFC) signal known exactly but variable task with a simulated signal embedded in real x-ray coronary angiogram backgrounds. The results showed that the internal noise method that led to the best prediction of human performance differed across the studied model observers. The CHO model best predicted human observer performance with the channel internal noise. The HO and LGHO best predicted human observer performance with the decision variable internal noise. The present results might guide researchers with the choice of methods to include internal noise into Hotelling model observers when evaluating and optimizing medical image quality

  12. Post commissioning noise study

    International Nuclear Information System (INIS)

    Heraud, P.

    2008-01-01

    This presentation described a wind farm post-commissioning study conducted at a wind farm owned by Helimax Energy Inc. The farm was located in a partly-forested, partly cultivated region in Quebec that featured gently rolling hills. Over 600 dwellings were located within 2 km of the wind farm, and 44 dwellings were within the wind farm's boundaries. The noise impact assessments were conducted at various points near the wind farm. The wind farm was designed using an International Standards Organization (ISO) noise propagation model and a 40 dBA to provide adequate setbacks. The study was conducted using 10 days of continuous measurements at selected points of a wind farm. Points of reception included points from 650 m to 800 m. Noise over 2 km was not thought to be contributed by the wind turbine. The nearest dwelling was 512 m from one of the farm's wind turbines. The study also considered ground factor, temperature, relative humidity, and the height of the receptors. Quebec noise level limits are 40 dBA at night, and 45 dBA during the day. Noise level limits are independent of wind speed. Measured noise contributions over 40 dBA were not observed during the measurement program. The wind turbines were only audible for 1 night out of the 30 night study period. It was concluded that the ISO noise propagation model is a reliable tool for conducting noise impact assessments. tabs., figs

  13. Designing acoustics for linguistically diverse classrooms: Effects of background noise, reverberation and talker foreign accent on speech comprehension by native and non-native English-speaking listeners

    Science.gov (United States)

    Peng, Zhao Ellen

    The current classroom acoustics standard (ANSI S12.60-2010) recommends core learning spaces not to exceed background noise level (BNL) of 35 dBA and reverberation time (RT) of 0.6 second, based on speech intelligibility performance mainly by the native English-speaking population. Existing literature has not correlated these recommended values well with student learning outcomes. With a growing population of non-native English speakers in American classrooms, the special needs for perceiving degraded speech among non-native listeners, either due to realistic room acoustics or talker foreign accent, have not been addressed in the current standard. This research seeks to investigate the effects of BNL and RT on the comprehension of English speech from native English and native Mandarin Chinese talkers as perceived by native and non-native English listeners, and to provide acoustic design guidelines to supplement the existing standard. This dissertation presents two studies on the effects of RT and BNL on more realistic classroom learning experiences. How do native and non-native English-speaking listeners perform on speech comprehension tasks under adverse acoustic conditions, if the English speech is produced by talkers of native English (Study 1) versus native Mandarin Chinese (Study 2)? Speech comprehension materials were played back in a listening chamber to individual listeners: native and non-native English-speaking in Study 1; native English, native Mandarin Chinese, and other non-native English-speaking in Study 2. Each listener was screened for baseline English proficiency level, and completed dual tasks simultaneously involving speech comprehension and adaptive dot-tracing under 15 acoustic conditions, comprised of three BNL conditions (RC-30, 40, and 50) and five RT scenarios (0.4 to 1.2 seconds). The results show that BNL and RT negatively affect both objective performance and subjective perception of speech comprehension, more severely for non

  14. Progress in Noise Thermometry at 505 K and 693 K Using Quantized Voltage Noise Ratio Spectra

    Science.gov (United States)

    Tew, W. L.; Benz, S. P.; Dresselhaus, P. D.; Coakley, K. J.; Rogalla, H.; White, D. R.; Labenski, J. R.

    2010-09-01

    Technical advances and new results in noise thermometry at temperatures near the tin freezing point and the zinc freezing point using a quantized voltage noise source (QVNS) are reported. The temperatures are derived by comparing the power spectral density of QVNS synthesized noise with that of Johnson noise from a known resistance at both 505 K and 693 K. Reference noise is digitally synthesized so that the average power spectra of the QVNS match those of the thermal noise, resulting in ratios of power spectra close to unity in the low-frequency limit. Three-parameter models are used to account for differences in impedance-related time constants in the spectra. Direct comparison of noise temperatures to the International Temperature Scale of 1990 (ITS-90) is achieved in a comparison furnace with standard platinum resistance thermometers. The observed noise temperatures determined by operating the noise thermometer in both absolute and relative modes, and related statistics together with estimated uncertainties are reported. The relative noise thermometry results are combined with results from other thermodynamic determinations at temperatures near the tin freezing point to calculate a value of T - T 90 = +4(18) mK for temperatures near the zinc freezing point. These latest results achieve a lower uncertainty than that of our earlier efforts. The present value of T - T 90 is compared to other published determinations from noise thermometry and other methods.

  15. Assessment of Traffic Noise Impacts

    DEFF Research Database (Denmark)

    Rich, Jeppe Husted; Nielsen, Otto Anker

    2004-01-01

    A steady growth in traffic intensities in most urban areas throughout the world has forced planners and politicians to seriously consider the resulting environmental impact, such as traffic noise, accidents and air pollution. The assessment of such negative factors is needed in order to reveal...... the true social benefit of infrastructure plans. The paper presents a noise assessment model for the Copenhagen region, which brings together GIS technology and non-linear hedonic regression models to reveal the implicit costs of traffic noise measured as the marginal percentage loss in property values...

  16. Effect of non-tariff barriers on secondary processed wood product trade: New Zealand exports to the United States, China and Japan

    Science.gov (United States)

    James A. Turner; Joseph Buongiorno; Shushuai Zhu; Frances Maplesden

    2008-01-01

    Secondary processed wood products - builder's carpentry and joinery, moldings and millwork, wooden furniture, and prefabricated buildings - have grown significantly in importance in the global trade of wood products. At the same time there has been increased use of non-tariff barriers to restrict their trade.  These barriers could have an important impact on the...

  17. Non-surgical retreatment of a failed apicoectomy without retrofilling using white mineral trioxide aggregate as an apical barrier.

    Science.gov (United States)

    Stefopoulos, Spyridon; Tzanetakis, Giorgos N; Kontakiotis, Evangelos G

    2012-01-01

    Root-end resected teeth with persistent apical periodontitis are usually retreated surgically or a combination of non-surgical and surgical retreatment is employed. However, patients are sometimes unwilling to be subjected to a second surgical procedure. The apical barrier technique that is used for apical closure of immature teeth with necrotic pulps may be an alternative to non-surgically retreat a failed apicoectomy. Mineral trioxide aggregate (MTA) has become the material of choice in such cases because of its excellent biocompatibility, sealing ability and osseoinductive properties. This case report describes the non-surgical retreatment of a failed apicoectomy with no attempt at retrofilling of a maxillary central incisor. White MTA was used to induce apical closure of the wide resected apical area. Four-year follow-up examination revealed an asymptomatic, fully functional tooth with a satisfactory healing of the apical lesion. White MTA apical barrier may constitute a reliable and efficient technique to non-surgically retreat teeth with failed root-end resection. The predictability of such a treatment is of great benefit for the patient who is unwilling to be submitted to a second surgical procedure.

  18. Omnidirectional ventilated acoustic barrier

    Science.gov (United States)

    Zhang, Hai-long; Zhu, Yi-fan; Liang, Bin; Yang, Jing; Yang, Jun; Cheng, Jian-chun

    2017-11-01

    As an important problem in acoustics, sound insulation finds applications in a great variety of situations. In the existing schemes, however, there has always been a trade-off between the thinness of sound-insulating devices and their ventilating capabilities, limiting their potentials in the control of low-frequency sound in high ventilation environments. Here, we design and experimentally implement an omnidirectional acoustic barrier with a planar profile, subwavelength thickness ( 0.18 λ ), yet high ventilation. The proposed mechanism is based on the interference between the resonant scattering of discrete states and the background scattering of continuous states which induces a Fano-like asymmetric transmission profile. Benefitting from the binary-structured design of the coiled unit and hollow pipe, it maximally simplifies the design and fabrication while ensuring the ventilation for all the non-resonant units with open tubes. The simulated and measured results agree well, showing the effectiveness of our proposed mechanism to block low frequency sound coming from various directions while allowing 63% of the air flow to pass. We anticipate our design to open routes to design sound insulators and to enable applications in traditionally unattainable cases such as those calling for noise reduction and cooling simultaneously.

  19. Speech-in-Noise Tests and Supra-threshold Auditory Evoked Potentials as Metrics for Noise Damage and Clinical Trial Outcome Measures.

    Science.gov (United States)

    Le Prell, Colleen G; Brungart, Douglas S

    2016-09-01

    In humans, the accepted clinical standards for detecting hearing loss are the behavioral audiogram, based on the absolute detection threshold of pure-tones, and the threshold auditory brainstem response (ABR). The audiogram and the threshold ABR are reliable and sensitive measures of hearing thresholds in human listeners. However, recent results from noise-exposed animals demonstrate that noise exposure can cause substantial neurodegeneration in the peripheral auditory system without degrading pure-tone audiometric thresholds. It has been suggested that clinical measures of auditory performance conducted with stimuli presented above the detection threshold may be more sensitive than the behavioral audiogram in detecting early-stage noise-induced hearing loss in listeners with audiometric thresholds within normal limits. Supra-threshold speech-in-noise testing and supra-threshold ABR responses are reviewed here, given that they may be useful supplements to the behavioral audiogram for assessment of possible neurodegeneration in noise-exposed listeners. Supra-threshold tests may be useful for assessing the effects of noise on the human inner ear, and the effectiveness of interventions designed to prevent noise trauma. The current state of the science does not necessarily allow us to define a single set of best practice protocols. Nonetheless, we encourage investigators to incorporate these metrics into test batteries when feasible, with an effort to standardize procedures to the greatest extent possible as new reports emerge.

  20. Environmental impact of noise levels in and around opencast bauxite mine.

    Science.gov (United States)

    Kisku, G C; Barman, S C; Kidwai, M M; Bhargava, S K

    2002-01-01

    Until recently, noise pollution has not been paid adequate attention as air, water and land pollution. In order to assess (predict) the impact of bauxite mine noise on employees health and in and around bauxite mine environment, general noise sources and equipment noise were monitored. All these noise sources were compared with prescribed standard noise levels laid down by Central Pollution Control Board (CPCB). Data has also been compared with reference site, north block hill top which is barren and virgin plateau/top covered with grass only and free from human interference. Equipment noise levels were much higher than the other zone of the mine which does not have the corresponding standards. Rock breaker recorded the highest noise level with 73.1 +/- 14.2 to 89.5 +/- 10.1 dB (A) while from ripper dozer it was least with 61.0 +/- 17.3 to 76.2 +/- 6.2 dB (A). Meteorological parameters did not have much influence upon equipment noise up to 100 feet from the source.

  1. Semantic and phonetic enhancements for speech-in-noise recognition by native and non-native listeners.

    Science.gov (United States)

    Bradlow, Ann R; Alexander, Jennifer A

    2007-04-01

    Previous research has shown that speech recognition differences between native and proficient non-native listeners emerge under suboptimal conditions. Current evidence has suggested that the key deficit that underlies this disproportionate effect of unfavorable listening conditions for non-native listeners is their less effective use of compensatory information at higher levels of processing to recover from information loss at the phoneme identification level. The present study investigated whether this non-native disadvantage could be overcome if enhancements at various levels of processing were presented in combination. Native and non-native listeners were presented with English sentences in which the final word varied in predictability and which were produced in either plain or clear speech. Results showed that, relative to the low-predictability-plain-speech baseline condition, non-native listener final word recognition improved only when both semantic and acoustic enhancements were available (high-predictability-clear-speech). In contrast, the native listeners benefited from each source of enhancement separately and in combination. These results suggests that native and non-native listeners apply similar strategies for speech-in-noise perception: The crucial difference is in the signal clarity required for contextual information to be effective, rather than in an inability of non-native listeners to take advantage of this contextual information per se.

  2. Physics beyond the standard model in the non-perturbative unification scheme

    International Nuclear Information System (INIS)

    Kapetanakis, D.; Zoupanos, G.

    1990-01-01

    The non-perturbative unification scenario predicts reasonably well the low energy gauge couplings of the standard model. Agreement with the measured low energy couplings is obtained by assuming certain kind of physics beyond the standard model. A number of possibilities for physics beyond the standard model is examined. The best candidates so far are the standard model with eight fermionic families and a similar number of Higgs doublets, and the supersymmetric standard model with five families. (author)

  3. Socio-technical inertia: Understanding the barriers to electric vehicles

    International Nuclear Information System (INIS)

    Steinhilber, Simone; Wells, Peter; Thankappan, Samarthia

    2013-01-01

    It is widely accepted that electrification of the transport sector is one of several technological trajectories that could redress some of the environmental issues associated with the growth in travel demand including climate change and oil demand at a global scale, and air quality and noise pollution at the urban scale. Electric vehicles have been considered a promising technology at repeated intervals over the last century, but this promise has not been realised. This paper is a contribution to understanding the key tools and strategies that might enable the successful introduction of new technologies and innovations by exploring the key barriers to electric vehicles encountered in two countries (UK and Germany) where the automobile industry has been historically significant. The study evaluates stakeholders' opinions on relevant regulation, infrastructure investment, R and D incentives, and consumer incentives. The key findings of the research are that the introduction and penetration of EVs is confronted by several barriers that inhibit a larger market penetration under current conditions, which in turn casts doubt on the assumptions of strategic niche management and transitions theory. - Highlights: • Immature developing technology reason behind non-commercialisation of EVs. • EVs currently do not present a significant benefit to the electricity sector. • EVs rely on a mix of regulatory and government measures for their development. • EVs face lock-in problem of unsustainable technologies and related barriers. • Positive milieu for innovation in vehicle technology and business models are required

  4. Impact of image noise on gamma index calculation

    International Nuclear Information System (INIS)

    Chen, M; Mo, X; Parnell, D; Olivera, G; Galmarini, D; Lu, W

    2014-01-01

    Purpose: The Gamma Index defines an asymmetric metric between the evaluated image and the reference image. It provides a quantitative comparison that can be used to indicate sample-wised pass/fail on the agreement of the two images. The Gamma passing/failing rate has become an important clinical evaluation tool. However, the presence of noise in the evaluated and/or reference images may change the Gamma Index, hence the passing/failing rate, and further, clinical decisions. In this work, we systematically studied the impact of the image noise on the Gamma Index calculation. Methods: We used both analytic formulation and numerical calculations in our study. The numerical calculations included simulations and clinical images. Three different noise scenarios were studied in simulations: noise in reference images only, in evaluated images only, and in both. Both white and spatially correlated noises of various magnitudes were simulated. For clinical images of various noise levels, the Gamma Index of measurement against calculation, calculation against measurement, and measurement against measurement, were evaluated. Results: Numerical calculations for both the simulation and clinical data agreed with the analytic formulations, and the clinical data agreed with the simulations. For the Gamma Index of measurement against calculation, its distribution has an increased mean and an increased standard deviation as the noise increases. On the contrary, for the Gamma index of calculation against measurement, its distribution has a decreased mean and stabilized standard deviation as the noise increases. White noise has greater impact on the Gamma Index than spatially correlated noise. Conclusions: The noise has significant impact on the Gamma Index calculation and the impact is asymmetric. The Gamma Index should be reported along with the noise levels in both reference and evaluated images. Reporting of the Gamma Index with switched roles of the images as reference and

  5. Impact of Image Noise on Gamma Index Calculation

    Science.gov (United States)

    Chen, M.; Mo, X.; Parnell, D.; Olivera, G.; Galmarini, D.; Lu, W.

    2014-03-01

    Purpose: The Gamma Index defines an asymmetric metric between the evaluated image and the reference image. It provides a quantitative comparison that can be used to indicate sample-wised pass/fail on the agreement of the two images. The Gamma passing/failing rate has become an important clinical evaluation tool. However, the presence of noise in the evaluated and/or reference images may change the Gamma Index, hence the passing/failing rate, and further, clinical decisions. In this work, we systematically studied the impact of the image noise on the Gamma Index calculation. Methods: We used both analytic formulation and numerical calculations in our study. The numerical calculations included simulations and clinical images. Three different noise scenarios were studied in simulations: noise in reference images only, in evaluated images only, and in both. Both white and spatially correlated noises of various magnitudes were simulated. For clinical images of various noise levels, the Gamma Index of measurement against calculation, calculation against measurement, and measurement against measurement, were evaluated. Results: Numerical calculations for both the simulation and clinical data agreed with the analytic formulations, and the clinical data agreed with the simulations. For the Gamma Index of measurement against calculation, its distribution has an increased mean and an increased standard deviation as the noise increases. On the contrary, for the Gamma index of calculation against measurement, its distribution has a decreased mean and stabilized standard deviation as the noise increases. White noise has greater impact on the Gamma Index than spatially correlated noise. Conclusions: The noise has significant impact on the Gamma Index calculation and the impact is asymmetric. The Gamma Index should be reported along with the noise levels in both reference and evaluated images. Reporting of the Gamma Index with switched roles of the images as reference and

  6. Correlated Levy Noise in Linear Dynamical Systems

    International Nuclear Information System (INIS)

    Srokowski, T.

    2011-01-01

    Linear dynamical systems, driven by a non-white noise which has the Levy distribution, are analysed. Noise is modelled by a specific stochastic process which is defined by the Langevin equation with a linear force and the Levy distributed symmetric white noise. Correlation properties of the process are discussed. The Fokker-Planck equation driven by that noise is solved. Distributions have the Levy shape and their width, for a given time, is smaller than for processes in the white noise limit. Applicability of the adiabatic approximation in the case of the linear force is discussed. (author)

  7. THE NOISE IMMUNITY OF THE DIGITAL DEMODULATOR MFM-AM SIGNAL USED IN DATA COMMUNICATIONS SYSTEMS OF AIR TRAFFIC CONTROL WITH AUTOMATIC DEPENDENT SURVEILLANCE AGAINST A NON-GAUSSIAN NOISE

    Directory of Open Access Journals (Sweden)

    A. L. Senyavskiy

    2015-01-01

    Full Text Available The article analyzes the robustness of the digital demodulator of the signal with the lowest frequency shift keying at a subcarrier frequency with respect to non-Gaussian interference type of atmospheric, industrial noise and interfering frequency -and phase-shift keyed signals. This type of demodulator is used for the transmission of navigation data in the systems of air traffic control with automatic dependent surveillance.

  8. Fractal characterization for noise signal validation in power reactors

    International Nuclear Information System (INIS)

    Aguilar Martinez, Omar

    2003-01-01

    Up to now, a great variety of methods is used for the dynamical characterization of different components of Nuclear Power Plants (NPPs). With this aim, time and spectral analysis are usually considered, and different tools of non-stationary and non-gaussian analysis are also presented. When applying non-lineal dynamics theory for noise signal validation purposes in power reactors, the extraction of fractal echoes plays a main role. Fractal characterization for noise signal validation purposes can be integrated to the task of processing and acquisition of time signals in noise (fluctuation parameters) analysis systems. The possibility of discrimination between deterministic chaotic signals and pure noise signals has been incorporated, as a complement; to noise signals analysis in normal and anomalous operational conditions in NPPs using a fractal approach. In this work the detailed analysis of a neutronic sensor response is considered and the fractal characterization of its dynamics state (i.e. sensor line) for noise signal classification, it is presented. The experiment from where the time series (signals) were obtained, was carried out at the Research Reactor of the Technical University of Budapest, Hungary, during a model experiment for ageing process study of in-core neutron detectors (author)

  9. Non-standard and improperly posed problems

    CERN Document Server

    Straughan, Brian; Ames, William F

    1997-01-01

    Written by two international experts in the field, this book is the first unified survey of the advances made in the last 15 years on key non-standard and improperly posed problems for partial differential equations.This reference for mathematicians, scientists, and engineers provides an overview of the methodology typically used to study improperly posed problems. It focuses on structural stability--the continuous dependence of solutions on the initial conditions and the modeling equations--and on problems for which data are only prescribed on part of the boundary.The book addresses continuou

  10. Prediction of speech masking release for fluctuating interferers based on the envelope power signal-to-noise ratio

    DEFF Research Database (Denmark)

    Jørgensen, Søren; Dau, Torsten

    2012-01-01

    -hearing listeners in conditions with additive stationary noise, reverberation, and nonlinear processing with spectral subtraction. The latter condition represents a case in which the standardized speech intelligibility index and speech transmission index fail. However, the sEPSM is limited to conditions...... for the stationary and non-stationary interferers, demonstrating further that the envelope SNR is crucial for speech comprehension....

  11. Analysis and Extension of the Percentile Method, Estimating a Noise Curve from a Single Image

    Directory of Open Access Journals (Sweden)

    Miguel Colom

    2013-12-01

    Full Text Available Given a white Gaussian noise signal on a sampling grid, its variance can be estimated from a small block sample. However, in natural images we observe the combination of the geometry of the scene being photographed and the added noise. In this case, estimating directly the standard deviation of the noise from block samples is not reliable since the measured standard deviation is not explained just by the noise but also by the geometry of the image. The Percentile method tries to estimate the standard deviation of the noise from blocks of a high-passed version of the image and a small p-percentile of these standard deviations. The idea behind is that edges and textures in a block of the image increase the observed standard deviation but they never make it decrease. Therefore, a small percentile (0.5%, for example in the list of standard deviations of the blocks is less likely to be affected by the edges and textures than a higher percentile (50%, for example. The 0.5%-percentile is empirically proven to be adequate for most natural, medical and microscopy images. The Percentile method is adapted to signal-dependent noise, which is realistic with the Poisson noise model obtained by a CCD device in a digital camera.

  12. Non-linear gyrokinetic simulations of microturbulence in TCV electron internal transport barriers

    Science.gov (United States)

    Lapillonne, X.; Brunner, S.; Sauter, O.; Villard, L.; Fable, E.; Görler, T.; Jenko, F.; Merz, F.

    2011-05-01

    Using the local (flux-tube) version of the Eulerian code GENE (Jenko et al 2000 Phys. Plasmas 7 1904), gyrokinetic simulations of microturbulence were carried out considering parameters relevant to electron-internal transport barriers (e-ITBs) in the TCV tokamak (Sauter et al 2005 Phys. Rev. Lett. 94 105002), generated under conditions of low or negative shear. For typical density and temperature gradients measured in such barriers, the corresponding simulated fluctuation spectra appears to simultaneously contain longer wavelength trapped electron modes (TEMs, for typically k⊥ρi 0.5). The contributions to the electron particle flux from these two types of modes are, respectively, outward/inward and may cancel each other for experimentally realistic gradients. This mechanism may partly explain the feasibility of e-ITBs. The non-linear simulation results confirm the predictions of a previously developed quasi-linear model (Fable et al 2010 Plasma Phys. Control. Fusion 52 015007), namely that the stationary condition of zero particle flux is obtained through the competitive contributions of ITG and TEM. A quantitative comparison of the electron heat flux with experimental estimates is presented as well.

  13. Non-parametric system identification from non-linear stochastic response

    DEFF Research Database (Denmark)

    Rüdinger, Finn; Krenk, Steen

    2001-01-01

    An estimation method is proposed for identification of non-linear stiffness and damping of single-degree-of-freedom systems under stationary white noise excitation. Non-parametric estimates of the stiffness and damping along with an estimate of the white noise intensity are obtained by suitable...... of the energy at mean-level crossings, which yields the damping relative to white noise intensity. Finally, an estimate of the noise intensity is extracted by estimating the absolute damping from the autocovariance functions of a set of modified phase plane variables at different energy levels. The method...

  14. Can OPERA help in constraining neutrino non-standard interactions?

    Energy Technology Data Exchange (ETDEWEB)

    Esteban-Pretel, A.; Valle, J.W.F. [AHEP Group, Institut de Fisica Corpuscular, C.S.I.C./Universitat de Valencia, Edificio Institutos de Paterna, Apt 22085, E-46071 Valencia (Spain); Huber, P. [Theory Division, Department of Physics, CERN, CH-1211 Geneva 23 (Switzerland); Institute for Particle, Nuclear and Astronomical Sciences, Physics Department, Virgina Tech, Blacksburg, VA 24062 (United States)], E-mail: pahuber@vt.edu

    2008-10-09

    We study how much the unique ability of the OPERA experiment to directly detect {nu}{sub {tau}} can help in probing new, non-standard contact interactions of the third family of neutrinos. We perform a combined analysis of future, high-statistics MINOS and OPERA data. For the case of non-standard interactions in {nu}{sub {mu}} to {nu}{sub e} transitions we also include the impact of possible Double Chooz data. In all cases we find that the {nu}{sub {tau}} sample of OPERA is too small to be statistically significant, even if one doubles the nominal exposure of OPERA to 9x10{sup 19} pot. OPERA's real benefit for this measurement lies in its very high neutrino energy and hence very different L/E compared to MINOS.

  15. Schottky barrier MOSFET systems and fabrication thereof

    Science.gov (United States)

    Welch, J.D.

    1997-09-02

    (MOS) device systems-utilizing Schottky barrier source and drain to channel region junctions are disclosed. Experimentally derived results which demonstrate operation of fabricated N-channel and P-channel Schottky barrier (MOSFET) devices, and of fabricated single devices with operational characteristics similar to (CMOS) and to a non-latching (SRC) are reported. Use of essentially non-rectifying Schottky barriers in (MOS) structures involving highly doped and the like and intrinsic semiconductor to allow non-rectifying interconnection of, and electrical accessing of device regions is also disclosed. Insulator effected low leakage current device geometries and fabrication procedures therefore are taught. Selective electrical interconnection of drain to drain, source to drain, or source to source, of N-channel and/or P-channel Schottky barrier (MOSFET) devices formed on P-type, N-type and Intrinsic semiconductor allows realization of Schottky Barrier (CMOS), (MOSFET) with (MOSFET) load, balanced differential (MOSFET) device systems and inverting and non-inverting single devices with operating characteristics similar to (CMOS), which devices can be utilized in modulation, as well as in voltage controlled switching and effecting a direction of rectification. 89 figs.

  16. A novel segmentation method for uneven lighting image with noise injection based on non-local spatial information and intuitionistic fuzzy entropy

    Science.gov (United States)

    Yu, Haiyan; Fan, Jiulun

    2017-12-01

    Local thresholding methods for uneven lighting image segmentation always have the limitations that they are very sensitive to noise injection and that the performance relies largely upon the choice of the initial window size. This paper proposes a novel algorithm for segmenting uneven lighting images with strong noise injection based on non-local spatial information and intuitionistic fuzzy theory. We regard an image as a gray wave in three-dimensional space, which is composed of many peaks and troughs, and these peaks and troughs can divide the image into many local sub-regions in different directions. Our algorithm computes the relative characteristic of each pixel located in the corresponding sub-region based on fuzzy membership function and uses it to replace its absolute characteristic (its gray level) to reduce the influence of uneven light on image segmentation. At the same time, the non-local adaptive spatial constraints of pixels are introduced to avoid noise interference with the search of local sub-regions and the computation of local characteristics. Moreover, edge information is also taken into account to avoid false peak and trough labeling. Finally, a global method based on intuitionistic fuzzy entropy is employed on the wave transformation image to obtain the segmented result. Experiments on several test images show that the proposed method has excellent capability of decreasing the influence of uneven illumination on images and noise injection and behaves more robustly than several classical global and local thresholding methods.

  17. Noise-induced hearing loss

    Directory of Open Access Journals (Sweden)

    Mariola Sliwinska-Kowalska

    2012-01-01

    Full Text Available Noise-induced hearing loss (NIHL still remains a problem in developed countries, despite reduced occupational noise exposure, strict standards for hearing protection and extensive public health awareness campaigns. Therefore NIHL continues to be the focus of noise research activities. This paper summarizes progress achieved recently in our knowledge of NIHL. It includes papers published between the years 2008-2011 (in English, which were identified by a literature search of accessible medical and other relevant databases. A substantial part of this research has been concerned with the risk of NIHL in the entertainment sector, particularly in professional, orchestral musicians. There are also constant concerns regarding noise exposure and hearing risk in "hard to control" occupations, such as farming and construction work. Although occupational noise has decreased since the early 1980s, the number of young people subject to social noise exposure has tripled. If the exposure limits from the Noise at Work Regulations are applied, discotheque music, rock concerts, as well as music from personal music players are associated with the risk of hearing loss in teenagers and young adults. Several recent research studies have increased the understanding of the pathomechanisms of acoustic trauma, the genetics of NIHL, as well as possible dietary and pharmacologic otoprotection in acoustic trauma. The results of these studies are very promising and offer grounds to expect that targeted therapies might help prevent the loss of sensory hair cells and protect the hearing of noise-exposed individuals. These studies emphasize the need to launch an improved noise exposure policy for hearing protection along with developing more efficient norms of NIHL risk assessment.

  18. A simulation to study the feasibility of improving the temporal resolution of LAGEOS geodynamic solutions by using a sequential process noise filter

    Science.gov (United States)

    Hartman, Brian Davis

    1995-01-01

    A key drawback to estimating geodetic and geodynamic parameters over time based on satellite laser ranging (SLR) observations is the inability to accurately model all the forces acting on the satellite. Errors associated with the observations and the measurement model can detract from the estimates as well. These 'model errors' corrupt the solutions obtained from the satellite orbit determination process. Dynamical models for satellite motion utilize known geophysical parameters to mathematically detail the forces acting on the satellite. However, these parameters, while estimated as constants, vary over time. These temporal variations must be accounted for in some fashion to maintain meaningful solutions. The primary goal of this study is to analyze the feasibility of using a sequential process noise filter for estimating geodynamic parameters over time from the Laser Geodynamics Satellite (LAGEOS) SLR data. This evaluation is achieved by first simulating a sequence of realistic LAGEOS laser ranging observations. These observations are generated using models with known temporal variations in several geodynamic parameters (along track drag and the J(sub 2), J(sub 3), J(sub 4), and J(sub 5) geopotential coefficients). A standard (non-stochastic) filter and a stochastic process noise filter are then utilized to estimate the model parameters from the simulated observations. The standard non-stochastic filter estimates these parameters as constants over consecutive fixed time intervals. Thus, the resulting solutions contain constant estimates of parameters that vary in time which limits the temporal resolution and accuracy of the solution. The stochastic process noise filter estimates these parameters as correlated process noise variables. As a result, the stochastic process noise filter has the potential to estimate the temporal variations more accurately since the constraint of estimating the parameters as constants is eliminated. A comparison of the temporal

  19. Are more restrictive food cadmium standards justifiable health safety measures or opportunistic barriers to trade? An answer from economics and public health

    International Nuclear Information System (INIS)

    Figueroa B, Eugenio

    2008-01-01

    In the past, Cd regulations have imposed trade restrictions on foodstuffs from some developing countries seeking to access markets in the developed world and in recent years, there has been a trend towards imposing more rigorous standards. This trend seems to respond more to public and private sectors strategies in some developed countries to create disguised barriers to trade and to improve market competitiveness for their industries, than to scientifically justified health precautions (sanitary and phytosanitary measures) and/or technical barriers to trade acceptable under the Uruguay Round Agreement of the WTO. Applying more rigorous Cd standards in some developed countries will not only increase production costs in developing countries but it will also have a large impact on their economies highly dependent on international agricultural markets. In the current literature there are large uncertainties in the cause-effect relationship between current levels of Cd intakes and eventual health effects in human beings; even the risk of Cd to kidney function is under considerable debate. Recent works on the importance of zinc:Cd ratio rather than Cd levels alone to determine Cd risk factors, on the one hand, and on the declining trends of Cd level in foods and soils, on the other, also indicate a lack of scientific evidence justifying more restrictive cadmium standards. This shows that developing countries should fight for changing and making more transparent the current international structures and procedures for setting sanitary and phytosanitary measures and technical barriers to trade

  20. Are more restrictive food cadmium standards justifiable health safety measures or opportunistic barriers to trade? An answer from economics and public health.

    Science.gov (United States)

    Figueroa B, Eugenio

    2008-01-15

    In the past, Cd regulations have imposed trade restrictions on foodstuffs from some developing countries seeking to access markets in the developed world and in recent years, there has been a trend towards imposing more rigorous standards. This trend seems to respond more to public and private sectors strategies in some developed countries to create disguised barriers to trade and to improve market competitiveness for their industries, than to scientifically justified health precautions (sanitary and phytosanitary measures) and/or technical barriers to trade acceptable under the Uruguay Round Agreement of the WTO. Applying more rigorous Cd standards in some developed countries will not only increase production costs in developing countries but it will also have a large impact on their economies highly dependent on international agricultural markets. In the current literature there are large uncertainties in the cause-effect relationship between current levels of Cd intakes and eventual health effects in human beings; even the risk of Cd to kidney function is under considerable debate. Recent works on the importance of zinc:Cd ratio rather than Cd levels alone to determine Cd risk factors, on the one hand, and on the declining trends of Cd level in foods and soils, on the other, also indicate a lack of scientific evidence justifying more restrictive cadmium standards. This shows that developing countries should fight for changing and making more transparent the current international structures and procedures for setting sanitary and phytosanitary measures and technical barriers to trade.

  1. Curtailing the dark side in non-standard neutrino interactions

    Energy Technology Data Exchange (ETDEWEB)

    Coloma, Pilar [Theoretical Physics Department, Fermi National Accelerator Laboratory,P.O. Box 500, Batavia, IL 60510 (United States); Denton, Peter B. [Theoretical Physics Department, Fermi National Accelerator Laboratory,P.O. Box 500, Batavia, IL 60510 (United States); Niels Bohr International Academy, University of Copenhagen, The Niels Bohr Institute,Blegdamsvej 17, DK-2100, Copenhagen (Denmark); Gonzalez-Garcia, M.C. [Departament de Fisíca Quàntica i Astrofísica and Institut de Ciencies del Cosmos,Universitat de Barcelona, Diagonal 647, E-08028 Barcelona (Spain); Institució Catalana de Recerca i Estudis Avançats (ICREA),Pg. Lluis Companys 23, 08010 Barcelona (Spain); C.N. Yang Institute for Theoretical Physics, Stony Brook University,Stony Brook, NY 11794-3840 (United States); Maltoni, Michele [Instituto de Física Teórica UAM/CSIC, Universidad Autónoma de Madrid,Calle de Nicolás Cabrera 13-15, Cantoblanco, E-28049 Madrid (Spain); Schwetz, Thomas [Institut für Kernphysik, Karlsruher Institut für Technologie (KIT), D-76021 Karlsruhe (Germany)

    2017-04-20

    In presence of non-standard neutrino interactions the neutrino flavor evolution equation is affected by a degeneracy which leads to the so-called LMA-Dark solution. It requires a solar mixing angle in the second octant and implies an ambiguity in the neutrino mass ordering. Non-oscillation experiments are required to break this degeneracy. We perform a combined analysis of data from oscillation experiments with the neutrino scattering experiments CHARM and NuTeV. We find that the degeneracy can be lifted if the non-standard neutrino interactions take place with down quarks, but it remains for up quarks. However, CHARM and NuTeV constraints apply only if the new interactions take place through mediators not much lighter than the electroweak scale. For light mediators we consider the possibility to resolve the degeneracy by using data from future coherent neutrino-nucleus scattering experiments. We find that, for an experiment using a stopped-pion neutrino source, the LMA-Dark degeneracy will either be resolved, or the presence of new interactions in the neutrino sector will be established with high significance.

  2. HF DBD plasma actuators for reduction of cylinder noise in flow

    Science.gov (United States)

    Kopiev, V. F.; Kazansky, P. N.; Kopiev, V. A.; Moralev, I. A.; Zaytsev, M. Yu

    2017-11-01

    Surface high frequency dielectric barrier discharge (HF DBD) was used to reduce flow-induced noise, radiated by circular cylinder in cross flow. Effect of HF DBD actuators is studied for flow velocity up to 80 m s-1 (Reynolds numbers up to 2.18 · 105), corresponding to the typical aircraft landing approach speed. Noise measurements were performed by microphone array in anechoic chamber; averaged flow parameters were studied by particle image velocimetry (PIV). Actuator was powered by high-frequency voltage in hundreds kHz range in steady or modulated mode with the modulation frequency of 0.3-20 kHz (Strouhal number St of 0.4 to 20). It is demonstrated that upstream directed plasma actuators are able to reduce the vortex noise of a cylinder by 10 dB. Noise reduction is accompanied by significant reorganization of the wake behind a cylinder, decreasing both wake width and turbulence level. The physical mechanism related to broadband noise control by HF DBD actuator is also discussed.

  3. Zero Thermal Noise in Resistors at Zero Temperature

    Science.gov (United States)

    Kish, Laszlo B.; Niklasson, Gunnar A.; Granqvist, Claes-Göran

    2016-06-01

    The bandwidth of transistors in logic devices approaches the quantum limit, where Johnson noise and associated error rates are supposed to be strongly enhanced. However, the related theory — asserting a temperature-independent quantum zero-point (ZP) contribution to Johnson noise, which dominates the quantum regime — is controversial and resolution of the controversy is essential to determine the real error rate and fundamental energy dissipation limits of logic gates in the quantum limit. The Callen-Welton formula (fluctuation-dissipation theorem) of voltage and current noise for a resistance is the sum of Nyquist’s classical Johnson noise equation and a quantum ZP term with a power density spectrum proportional to frequency and independent of temperature. The classical Johnson-Nyquist formula vanishes at the approach of zero temperature, but the quantum ZP term still predicts non-zero noise voltage and current. Here, we show that this noise cannot be reconciled with the Fermi-Dirac distribution, which defines the thermodynamics of electrons according to quantum-statistical physics. Consequently, Johnson noise must be nil at zero temperature, and non-zero noise found for certain experimental arrangements may be a measurement artifact, such as the one mentioned in Kleen’s uncertainty relation argument.

  4. REDUCTION OF CLASSROOM NOISE LEVELS USING GROUP CONTINGENCIES

    OpenAIRE

    Ring, Brandon M.; Sigurdsson, Sigurdur O.; Eubanks, Sean L.; Silverman, Kenneth

    2014-01-01

    The therapeutic workplace is an employment-based abstinence reinforcement intervention for unemployed drug users where trainees receive on-the-job employment skills training in a classroom setting. The study is an extension of prior therapeutic workplace research, which suggested that trainees frequently violated noise standards. Participants received real-time graphed feedback of noise levels and had the opportunity to earn monetary group reinforcement for maintaining a low number of noise v...

  5. Ultra-cold WIMPs relics of non-standard pre-BBN cosmologies

    CERN Document Server

    Gelmini, Graciela B

    2008-01-01

    We point out that in scenarios in which the Universe evolves in a non-standard manner during and after the kinetic decoupling of weakly interacting massive particles (WIMPs), these relics can be much colder than in standard cosmological scenarios (i.e. can be ultra-cold), possibly leading to the formation of smaller first objects in hierarchical structure formation scenarios.

  6. Exponential synchronization of delayed neutral-type neural networks with Lévy noise under non-Lipschitz condition

    Science.gov (United States)

    Ma, Shuo; Kang, Yanmei

    2018-04-01

    In this paper, the exponential synchronization of stochastic neutral-type neural networks with time-varying delay and Lévy noise under non-Lipschitz condition is investigated for the first time. Using the general Itô's formula and the nonnegative semi-martingale convergence theorem, we derive general sufficient conditions of two kinds of exponential synchronization for the drive system and the response system with adaptive control. Numerical examples are presented to verify the effectiveness of the proposed criteria.

  7. Analytical model for the TeraHertz current noise in nanometric Schottky-barrier diodes and heterostructure barrier varactors

    Energy Technology Data Exchange (ETDEWEB)

    Mahi, F Z; Helmaoui, A [Physics of Semiconductor Devices Laboratory (LPDS), University of Bechar (Algeria); Varani, L [Institute of Electronics of the South (IES - CNRS UMR 5214), University of Montpellier (France); Shiktorov, P; Starikov, E; Gruzhinskis, V, E-mail: fati_zo_mahi2002@yahoo.f [Semiconductor Physics Institute, Vilnius (Lithuania)

    2009-11-15

    In this paper we propose an analytical model for the calculation of the spectral density of current fluctuations in Heterostructure-barrier varactors . The structures of the calculated spectra are analyzed in terms of physical processes useful to optimize the device parameters for the extraction of the high-order harmonics.

  8. The Sunet System for Monitoring Noise Pollution in Cluj-Napoca

    Directory of Open Access Journals (Sweden)

    Beca Ilinca Mirela

    2017-12-01

    Full Text Available In Europe the need for local authorities to provide a high standard of living for their communities led to the establishment of the European noise mapping directive 2002/49/EC. Whilst Noise mapping itself doesn’t need continuous noise monitoring, states must produce a noise action plan which highlights actions they intend to take to reduce the number of people affected.

  9. Converse Barrier Certificate Theorem

    DEFF Research Database (Denmark)

    Wisniewski, Rafael; Sloth, Christoffer

    2013-01-01

    This paper presents a converse barrier certificate theorem for a generic dynamical system.We show that a barrier certificate exists for any safe dynamical system defined on a compact manifold. Other authors have developed a related result, by assuming that the dynamical system has no singular...... points in the considered subset of the state space. In this paper, we redefine the standard notion of safety to comply with generic dynamical systems with multiple singularities. Afterwards, we prove the converse barrier certificate theorem and illustrate the differences between ours and previous work...

  10. The Use of the Kurtosis-Adjusted Cumulative Noise Exposure Metric in Evaluating the Hearing Loss Risk for Complex Noise.

    Science.gov (United States)

    Xie, Hong-Wei; Qiu, Wei; Heyer, Nicholas J; Zhang, Mei-Bian; Zhang, Peng; Zhao, Yi-Ming; Hamernik, Roger P

    2016-01-01

    To test a kurtosis-adjusted cumulative noise exposure (CNE) metric for use in evaluating the risk of hearing loss among workers exposed to industrial noises. Specifically, to evaluate whether the kurtosis-adjusted CNE (1) provides a better association with observed industrial noise-induced hearing loss, and (2) provides a single metric applicable to both complex (non-Gaussian [non-G]) and continuous or steady state (Gaussian [G]) noise exposures for predicting noise-induced hearing loss (dose-response curves). Audiometric and noise exposure data were acquired on a population of screened workers (N = 341) from two steel manufacturing plants located in Zhejiang province and a textile manufacturing plant located in Henan province, China. All the subjects from the two steel manufacturing plants (N = 178) were exposed to complex noise, whereas the subjects from textile manufacturing plant (N = 163) were exposed to a G continuous noise. Each subject was given an otologic examination to determine their pure-tone HTL and had their personal 8-hr equivalent A-weighted noise exposure (LAeq) and full-shift noise kurtosis statistic (which is sensitive to the peaks and temporal characteristics of noise exposures) measured. For each subject, an unadjusted and kurtosis-adjusted CNE index for the years worked was created. Multiple linear regression analysis controlling for age was used to determine the relationship between CNE (unadjusted and kurtosis adjusted) and the mean HTL at 3, 4, and 6 kHz (HTL346) among the complex noise-exposed group. In addition, each subject's HTLs from 0.5 to 8.0 kHz were age and sex adjusted using Annex A (ISO-1999) to determine whether they had adjusted high-frequency noise-induced hearing loss (AHFNIHL), defined as an adjusted HTL shift of 30 dB or greater at 3.0, 4.0, or 6.0 kHz in either ear. Dose-response curves for AHFNIHL were developed separately for workers exposed to G and non-G noise using both unadjusted and adjusted CNE as the exposure

  11. 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...

  12. Controlling the spin-torque efficiency with ferroelectric barriers

    KAUST Repository

    Useinov, A.; Chshiev, M.; Manchon, Aurelien

    2015-01-01

    Nonequilibrium spin-dependent transport in magnetic tunnel junctions comprising a ferroelectric barrier is theoretically investigated. The exact solutions of the free electron Schrödinger equation for electron tunneling in the presence of interfacial screening are obtained by combining Bessel and Airy functions. We demonstrate that the spin transfer torque efficiency, and more generally the bias dependence of tunneling magneto- and electroresistance, can be controlled by switching the ferroelectric polarization of the barrier. In particular, the critical voltage at which the in-plane torque changes sign can be strongly enhanced or reduced depending on the direction of the ferroelectric polarization of the barrier. This effect provides a supplementary way to electrically control the current-driven dynamic states of the magnetization and related magnetic noise in spin transfer devices.

  13. Controlling the spin-torque efficiency with ferroelectric barriers

    KAUST Repository

    Useinov, A.

    2015-02-11

    Nonequilibrium spin-dependent transport in magnetic tunnel junctions comprising a ferroelectric barrier is theoretically investigated. The exact solutions of the free electron Schrödinger equation for electron tunneling in the presence of interfacial screening are obtained by combining Bessel and Airy functions. We demonstrate that the spin transfer torque efficiency, and more generally the bias dependence of tunneling magneto- and electroresistance, can be controlled by switching the ferroelectric polarization of the barrier. In particular, the critical voltage at which the in-plane torque changes sign can be strongly enhanced or reduced depending on the direction of the ferroelectric polarization of the barrier. This effect provides a supplementary way to electrically control the current-driven dynamic states of the magnetization and related magnetic noise in spin transfer devices.

  14. Preschool Personnel Exposure to Occupational Noise

    Directory of Open Access Journals (Sweden)

    Kaļužnaja Darja

    2016-10-01

    Full Text Available Increased noise, which is also below the occupational exposure values and is “hearing safe” noise, affects the exposed person’s health as a non-specific stressor. Increased noise level also creates an environment for additional vocal apparatus load. The objective of this study was to determine preschool personnel occupational noise and its relationship with subjective health complaints. Data were obtained with survey assistance through subjective answers of respondents about health complaints and noise exposure among Rīga preschool personnel. Objective noise measurements were made to assess real noise levels in the preschool environment. Data from 155 respondents and objective measurements of 37 preschool classrooms were obtained. The results showed that the average 8-h noise exposure among Rīga preschool educational institutions was 70 dB(A, which did not exceed the Latvian work environment noise limits, but exceeded the 35–40 dB(A noise limit in the educational environment guidelines recommended by the WHO. The survey results showed that loud noise is one of the most important workplace environmental factors (~70% of respondents feel a necessity to increase voice because of noise. A constant feeling of fatigue, headache, irritable feeling, and a desire to isolate oneself from others more often occurred in respondents exposed to increased noise, compared with those who noted that they were not exposed to increased noise. In general, loud noise was associated with increased subjective health complaints in preschool education institution personnel.

  15. Collectivism versus individualism: performance-related pay and union coverage for non-standard workers in Britain

    OpenAIRE

    Booth, Alison L.; Francesconi, Marco

    2000-01-01

    This paper documents the extent of union coverage and performance-related pay (PRP) - the latter representing one aspect of pay flexibility - across standard and non-standard workers in Britain, using the first seven waves of the British Household Panel Survey, 1991-1997. We find there is no evidence of expansion of either union coverage or PRP towards any type of non-standard employment in the 1990s. Thus union rhetoric about a 'strategy of enlargement' towards non-standard workers remains j...

  16. 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.

  17. Road Traffic Noise Pollution Analysis for Cernavoda City

    Science.gov (United States)

    Manea, L.; Manea, A.; Florea, D.; Tarulescu, S.

    2017-10-01

    In the present paper was studied the noise pollution in Cernavodă city. The noise measurements were made for nine intersections from different city areas. Noise measurements were taken for three chosen routes with high population density, heavy traffic, commercial and residential buildings. Average, maximum and minimum values were collected and compared with standards. The impact of road traffic noise on the community depends on various factors such as road location and design, land use planning measures, building design, traffic composition, driver behaviour and the relief. In the study area 9 locations are identified to measure noise level. By using sound level meter noise levels are measured at different peak sessions i.e. morning, afternoon and evening. The presented values were collected for evening rush hour.

  18. Gravitational wave detection using laser interferometry beyond the standard quantum limit

    Science.gov (United States)

    Heurs, M.

    2018-05-01

    Interferometric gravitational wave detectors (such as advanced LIGO) employ high-power solid-state lasers to maximize their detection sensitivity and hence their reach into the universe. These sophisticated light sources are ultra-stabilized with regard to output power, emission frequency and beam geometry; this is crucial to obtain low detector noise. However, even when all laser noise is reduced as far as technically possible, unavoidable quantum noise of the laser still remains. This is a consequence of the Heisenberg Uncertainty Principle, the basis of quantum mechanics: in this case, it is fundamentally impossible to simultaneously reduce both the phase noise and the amplitude noise of a laser to arbitrarily low levels. This fact manifests in the detector noise budget as two distinct noise sources-photon shot noise and quantum radiation pressure noise-which together form a lower boundary for current-day gravitational wave detector sensitivities, the standard quantum limit of interferometry. To overcome this limit, various techniques are being proposed, among them different uses of non-classical light and alternative interferometer topologies. This article explains how quantum noise enters and manifests in an interferometric gravitational wave detector, and gives an overview of some of the schemes proposed to overcome this seemingly fundamental limitation, all aimed at the goal of higher gravitational wave event detection rates. This article is part of a discussion meeting issue `The promises of gravitational-wave astronomy'.

  19. 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...

  20. Asymmetric dark matter annihilation as a test of non-standard cosmologies

    International Nuclear Information System (INIS)

    Gelmini, Graciela B.; Huh, Ji-Haeng; Rehagen, Thomas

    2013-01-01

    We show that the relic abundance of the minority component of asymmetric dark matter can be very sensitive to the expansion rate of the Universe and the temperature of transition between a non-standard pre-Big Bang Nucleosynthesis cosmological phase and the standard radiation dominated phase, if chemical decoupling happens before this transition. In particular, because the annihilation cross section of asymmetric dark matter is typically larger than that of symmetric dark matter in the standard cosmology, the decrease in relic density of the minority component in non-standard cosmologies with respect to the majority component may be compensated by the increase in annihilation cross section, so that the annihilation rate at present of asymmetric dark matter, contrary to general belief, could be larger than that of symmetric dark matter in the standard cosmology. Thus, if the annihilation cross section of the asymmetric dark matter candidate is known, the annihilation rate at present, if detectable, could be used to test the Universe before Big Bang Nucleosynthesis, an epoch from which we do not yet have any data