Application of Macro Response Monte Carlo method for electron spectrum simulation

International Nuclear Information System (INIS)

Perles, L.A.; Almeida, A. de

2007-01-01

During the past years several variance reduction techniques for Monte Carlo electron transport have been developed in order to reduce the electron computation time transport for absorbed dose distribution. We have implemented the Macro Response Monte Carlo (MRMC) method to evaluate the electron spectrum which can be used as a phase space input for others simulation programs. Such technique uses probability distributions for electron histories previously simulated in spheres (called kugels). These probabilities are used to sample the primary electron final state, as well as the creation secondary electrons and photons. We have compared the MRMC electron spectra simulated in homogeneous phantom against the Geant4 spectra. The results showed an agreement better than 6% in the spectra peak energies and that MRMC code is up to 12 time faster than Geant4 simulations

Response spectrum analysis of coupled structural response to a three component seismic disturbance

International Nuclear Information System (INIS)

Boulet, J.A.M.; Carley, T.G.

1977-01-01

The work discussed herein is a comparison and evaluation of several response spectrum analysis (RSA) techniques as applied to the same structural model with seismic excitation having three spatial components. Lagrange's equations of motion for the system were written in matrix form and uncoupled with the modal matrix. Numerical integration (fourth order Runge-Kutta) of the resulting model equations produced time histories of system displacements in response to simultaneous application of three orthogonal components of ground motion, and displacement response spectra for each modal coordinate in response to each of the three ground motion components. Five different RSA techniques were used to combine the spectral displacements and the modal matrix to give approximations of maximum system displacements. These approximations were then compared with the maximum system displacements taken from the time histories. The RSA techniques used are the method of absolute sums, the square root of the sum of the squares, the double sum approach, the method of closely spaced modes, and Lin's method. The vectors of maximum system displacements as computed by the time history analysis and the five response spectrum analysis methods are presented. (Auth.)

Multiple Beta Spectrum Analysis Method Based on Spectrum Fitting

Energy Technology Data Exchange (ETDEWEB)

Lee, Uk Jae; Jung, Yun Song; Kim, Hee Reyoung [UNIST, Ulsan (Korea, Republic of)

2016-05-15

When the sample of several mixed radioactive nuclides is measured, it is difficult to divide each nuclide due to the overlapping of spectrums. For this reason, simple mathematical analysis method for spectrum analysis of the mixed beta ray source has been studied. However, existing research was in need of more accurate spectral analysis method as it has a problem of accuracy. The study will describe the contents of the separation methods of the mixed beta ray source through the analysis of the beta spectrum slope based on the curve fitting to resolve the existing problem. The fitting methods including It was understood that sum of sine fitting method was the best one of such proposed methods as Fourier, polynomial, Gaussian and sum of sine to obtain equation for distribution of mixed beta spectrum. It was shown to be the most appropriate for the analysis of the spectrum with various ratios of mixed nuclides. It was thought that this method could be applied to rapid spectrum analysis of the mixed beta ray source.

Neutron spectrum measurement using rise-time discrimination method

International Nuclear Information System (INIS)

Luo Zhiping; Suzuki, C.; Kosako, T.; Ma Jizeng

2009-01-01

PSD method can be used to measure the fast neutron spectrum in n/γ mixed field. A set of assemblies for measuring the pulse height distribution of neutrons is built up,based on a large volume NE213 liquid scintillator and standard NIM circuits,through the rise-time discrimination method. After that,the response matrix is calculated using Monte Carlo method. The energy calibration of the pulse height distribution is accomplished using 60 Co radioisotope. The neutron spectrum of the mono-energetic accelerator neutron source is achieved by unfolding process. Suggestions for further improvement of the system are presented at last. (authors)

Consideration of vertical seismic response spectrum in nuclear safety review

International Nuclear Information System (INIS)

Sun Zaozhan; Huang Bingchen

2011-01-01

The basic requirements for civil nuclear installation are introduced in the article. Starting from the basic concept of seismic response spectrum, the authors analyze the site seismic response spectrum and the design seismic response spectrum that desire much consideration. By distinguishing the absolute seismic response spectrum and relative seismic response spectrum, the authors analyze the difference and relationship between the vertical seismic response spectrum and horizontal seismic response spectrum. The authors also bring forward some suggestions for determining the site vertical seismic response spectrum by considering the fact in our country. (authors)

Fast radio burst search: cross spectrum vs. auto spectrum method

Science.gov (United States)

Liu, Lei; Zheng, Weimin; Yan, Zhen; Zhang, Juan

2018-06-01

The search for fast radio bursts (FRBs) is a hot topic in current radio astronomy studies. In this work, we carry out a single pulse search with a very long baseline interferometry (VLBI) pulsar observation data set using both auto spectrum and cross spectrum search methods. The cross spectrum method, first proposed in Liu et al., maximizes the signal power by fully utilizing the fringe phase information of the baseline cross spectrum. The auto spectrum search method is based on the popular pulsar software package PRESTO, which extracts single pulses from the auto spectrum of each station. According to our comparison, the cross spectrum method is able to enhance the signal power and therefore extract single pulses from data contaminated by high levels of radio frequency interference (RFI), which makes it possible to carry out a search for FRBs in regular VLBI observations when RFI is present.

Effect of PVRC damping with independent support motion response spectrum analysis of piping systems

International Nuclear Information System (INIS)

Wang, Y.K.; Bezler, P.; Shteyngart, S.

1986-01-01

The Technical Committee for Piping Systems of the Pressure Vessel Research Committee (PVRC) has recommended new damping values to be used in the seismic analyses of piping systems in nuclear power plants. To evaluate the effects of coupling these recommendations with the use of independent support motion analyses methods, two sets of seismic analyses have been carried out for several piping systems. One set based on the use of uniform damping as specified in Regulatory Guide 1.61, the other based on the PVRC recommendations. In each set the analyses were performed using independent support motion time history and response spectrum methods as well as the envelope spectrum method. In the independent response spectrum analyses, 14 response estimates were in fact obtained by considering different combination procedures between the support group contributions and all sequences of combinations between support groups, modes and directions. For each analysis set, the response spectrum results were compared with time history estimates of those results. Comparison tables were then prepared depicting the percentage by which the response spectrum estimates exceeded the time history estimates. By comparing the result tables between both analysis sets, the impact of PVRC damping can be observed. Preliminary results show that the degree of exceedance of the response spectrum estimates based on PVRC damping is less than that based on uniform damping for the same piping problem. Expressed differently the results obtained if ISM methods are coupled with PVRC damping are not as conservative as those obtained using uniform damping

On nonstationarity-related errors in modal combination rules of the response spectrum method

Science.gov (United States)

Pathak, Shashank; Gupta, Vinay K.

2017-10-01

Characterization of seismic hazard via (elastic) design spectra and the estimation of linear peak response of a given structure from this characterization continue to form the basis of earthquake-resistant design philosophy in various codes of practice all over the world. Since the direct use of design spectrum ordinates is a preferred option for the practicing engineers, modal combination rules play central role in the peak response estimation. Most of the available modal combination rules are however based on the assumption that nonstationarity affects the structural response alike at the modal and overall response levels. This study considers those situations where this assumption may cause significant errors in the peak response estimation, and preliminary models are proposed for the estimation of the extents to which nonstationarity affects the modal and total system responses, when the ground acceleration process is assumed to be a stationary process. It is shown through numerical examples in the context of complete-quadratic-combination (CQC) method that the nonstationarity-related errors in the estimation of peak base shear may be significant, when strong-motion duration of the excitation is too small compared to the period of the system and/or the response is distributed comparably in several modes. It is also shown that these errors are reduced marginally with the use of the proposed nonstationarity factor models.

Analytical procedure in aseismic design of eccentric structure using response spectrum

International Nuclear Information System (INIS)

Takemori, T.; Kuwabara, Y.; Suwabe, A.; Mitsunobu, S.

1977-01-01

In this paper, the response are evaluated by the following two methods by the use of the typical torsional analytical models in which masses, rigidities, eccentricities between the centers thereof and several actual earthquake waves are taken as the parameters: (1) the root mean square of responses by using the response spectra derived from the earthquake waves, (2) the time history analysis by using the earthquake wave. The earthquake waves used are chosen to present the different frequency content and magnitude of the response spectra. The typical results derived from the study are as follows: (a) the response accelerations of mass center in the input earthquake direction by the (1) method coincide comparatively well with those by the (2) method, (b) the response accelerations perpendicular to the input earthquake direction by (1) method are 2 to 3 times as much as those by the (2) method, (c) the amplification of the response accelerations at arbitrary points distributed on the spread mass to those of center of the lumped mass by the (1) method are remarkably large compared with those by the (2) method in both directions respectively. These problems on the response spectrum analysis for the above-mentioned eccentric structure are discussed, and an improved analytical method applying the amplification coefficients of responses derived from this parametric time history analysis is proposed to the actual seismic design by the using of the given design ground response spectrum with root mean square technique

Seismic response of structures by the response spectrum method

International Nuclear Information System (INIS)

Hadjian, A.H.

1981-01-01

The problems of the acceleration profile at the lower elevations of cantilever structures and the response of relatively rigid structures are explored. It is shown that the use of the conventional methods for the above problems provide very approximate results. An alternate combination of the modal responses is proposed that not only resolves the above problems but also provides better estimates of response for the complete range of structure frequencies. The procedure treats the relative and rigid body responses separately and then appropriately combines the two results. For the rigid range of frequencies (fundamental frequencies greater than about 2 Hz), the proposed procedure does not encounter any numerical difficulties because of the additive nature of the component responses; however, the application of the proposed procedure for very flexible structures causes accuracy problems since the rigid body effects tend to be subtractive from the flexural response of about equal magnitude. For this latter class of problems, the conventional approach of modal combination provides adequate results and avoids the above mentioned numerical difficulties. (orig.)

Analytical solution for beam with time-dependent boundary conditions versus response spectrum

International Nuclear Information System (INIS)

Gou, P.F.; Panahi, K.K.

2001-01-01

This paper studies the responses of a uniform simple beam for which the supports are subjected to time-dependent conditions. Analytical solution in terms of series was presented for two cases: (1) Two supports of a simple beam are subjected to a harmonic motion, and (2) One of the two supports is stationary while the other is subjected to a harmonic motion. The results of the analytical solution were investigated and compared with the results of conventional response spectrum method using the beam finite element model. One of the applications of the results presented in this paper can be used to assess the adequacy and accuracy of the engineering approaches such as response spectra methods. It has been found that, when the excitation frequency equals the fundamental frequency of the beam, the results from response spectrum method are in good agreement with the exact calculation. The effects of initial conditions on the responses are also examined. It seems that the non-zero initial velocity has pronounced effects on the displacement time histories but it has no effect on the maximum accelerations. (author)

Modification of evaluation response spectrum by ductility of equipment anchorage

International Nuclear Information System (INIS)

Choi, I. G.; Jun, Y. S.; Su, J. M.

2003-01-01

The failure mode of welded anchorage is assumed as brittle in the seismic capacity evaluation of nuclear power plant equipments. But the welded anchorage has some ductile capacity. This limited displacement capacity can cause the reduction of the effective frequency of high frequency equipments and the increase of the inelastic energy absorption capacity due to the nonlinear behavior. In this study, the uniform hazard spectrum for Korean nuclear power plant site was modified using the response spectrum reduction factor developed by EPRI. The spectral acceleration for various damping ratio was determined by the theoretical method based on the random vibration theory. In conclusion, the high frequency components of evaluation response spectra were greatly reduced due to the consideration of welded anchorage ductility. This reduced response spectra can be used for the development of in-structure response spectra used in the seismic capacity evaluation of high frequency equipments

Response spectrum analysis of coupled structural response to a three component seismic disturbance

International Nuclear Information System (INIS)

Boulet, J.A.M.; Carley, T.G.

1977-01-01

The work discussed herein is a comparison and evaluation of several response spectrum analysis (RSA) techniques as applied to the same structural model with seismic excitation having three spatial components. The structural model includes five lumped masses (floors) connected by four elastic members. The base is supported by three translational springs and two horizontal torsional springs. In general, the mass center and shear center of a building floor are distinct locations. Hence, inertia forces, which act at the mass center, induce twisting in the structure. Through this induced torsion, the lateral (x and y) displacements of the mass elements are coupled. The ground motion components used for this study are artificial earthquake records generated from recorded accelerograms by a spectrum modification technique. The accelerograms have response spectra which are compatible with U.S. NRC Regulatory Guide 1.60. Lagrange's equations of motion for the system were written in matrix form and uncoupled with the modal matrix. Numerical integration (fourth order Runge-Kutta) of the resulting modal equations produced time histories of system displacements in response to simultaneous application of three orthogonal components of ground motion, and displacement response spectra for each modal coordinate in response to each of the three ground motion components. Five different RSA techniques were used to combine the spectral displacements and the modal matrix to give approximations of maximum system displacements. These approximations were then compared with the maximum system displacements taken from the time histories. The RSA techniques used are the method of absolute sums, the square root of the sum of the sum of the squares, the double sum approach, the method of closely spaced modes, and Lin's method

Numerical study of the mode selection in response spectrum analysis-condensed version

International Nuclear Information System (INIS)

Ng, D.S.

1986-01-01

For quality assurance of the dynamic response spectrum analysis, the Nuclear Regulatory Commission (NRC) recommends retaining all modes below the cutoff frequency at which the spectral acceleration (S/sub a/) returns to the peak zero period acceleration (ZPA). It also suggests that modes accounting for at least 90 percent of the structural masses be included in the analysis. A simple frame-type structure is generated as a baseline frame. Then groups of oscillators representing substructure are added onto the frame to study substructure behavior. A base case is established for each frame by including the specific number of modes used. The tests are conducted by incrementing the number of modes in the response spectrum analyses starting with one mode. The structural response of each modal increment is compared with the base case to identify the efficiency of mode selection method. All three methods are then applied to the MFTF-B Axicell Vacuum Vessel. The responses in critical components of the vessel, such as hangers and foundations, will be analyzed to confirm the accuracy of the selected method

Instantaneous response spectrum in seismic testing of nuclear power plant equipment

International Nuclear Information System (INIS)

Morrone, A.

1977-01-01

Seismic response spectra, as used in seismic analyses, give the maximum responses of single degree of freedom oscillators without consideration of the different time in the seismic time history at which each of the maximum responses occur. For response spectrum seismic analysis, the use of time-independent maximum responses is appropriate. The time dependece is considered in a statistical manner, for multi-degree of freedom systems, usually by combining the modal effects by the square root of the sum of the squares. For seismic testing of electrical equipment. IEEE Std. 344-1975 makes use of the response spectrum to define the input motion of the shake table. One of the basic requirements is that the test response spectrum (TRS) that is, the response spectrum produced by the shake table motion, should envelop the required response spectrum (RRS) calculated from the building analysis at the support point of the equipment being tested. This paper presents the concept of instantaneous response spectrum (IRS) as the response of single degree of freedom oscillators at a particular time. It demonstrates that a shake table random motion whose standard TRS envelops the RRS does not necessarily satisfy the enveloping requirement instantaneously. (Auth.)

Vertical Footbridge Vibrations: The Response Spectrum Methodology

DEFF Research Database (Denmark)

Georgakis, Christos; Ingólfsson, Einar Thór

2008-01-01

In this paper, a novel, accurate and readily codifiable methodology for the prediction of vertical footbridge response is presented. The methodology is based on the well-established response spectrum approach used in the majority of the world’s current seismic design codes of practice. The concept...... of a universally applicable reference response spectrum is introduced, from which the pedestrian-induced vertical response of any footbridge may be determined, based on a defined “event” and the probability of occurrence of that event. A series of Monte Carlo simulations are undertaken for the development...... period is introduced and its implication on the calculation of footbridge response is discussed. Finally, a brief comparison is made between the theoretically predicted pedestrian-induced vertical response of an 80m long RC footbridge (as an example) and actual field measurements. The comparison shows...

Power/response spectrum transformations in equipment qualification

International Nuclear Information System (INIS)

Unruh, J.F.; Kana, D.D.

1985-01-01

Since its introduction a few years ago the use of the power/response spectrum transformation has gained considerable interest and acceptance, and a number of new applications of the transformation have been developed in the equipment qualification area. A brief review of the power/response spectrum transformation is given with a discussion of the input/output relationships for linear systems required for elevated power spectrum generation. Frequency content of earthquakelike signals is discussed with emphasis on the resolution given by the PSD. The problem of excessive ZPA due to inconsistent spectra enveloping and mechanical nonlinearities is also discussed. The PSD/RS transformation is applied to the problems of combining various dynamic load events, developing bounding spectra, and developing damping consistent test spectra. Development of elevated component spectra corrected for base overtest and generation from in-situ measurements is reviewed

A spectrum correction method for fuel assembly rehomogenization

International Nuclear Information System (INIS)

Lee, Kyung Taek; Cho, Nam Zin

2004-01-01

To overcome the limitation of existing homogenization methods based on the single assembly calculation with zero current boundary condition, we propose a new rehomogenization method, named spectrum correction method (SCM), consisting of the multigroup energy spectrum approximation by spectrum correction and the condensed two-group heterogeneous single assembly calculations with non-zero current boundary condition. In SCM, the spectrum shifting phenomena caused by current across assembly interfaces are considered by the spectrum correction at group condensation stage at first. Then, heterogeneous single assembly calculations with two-group cross sections condensed by using corrected multigroup energy spectrum are performed to obtain rehomogenized nodal diffusion parameters, i.e., assembly-wise homogenized cross sections and discontinuity factors. To evaluate the performance of SCM, it was applied to the analytic function expansion nodal (AFEN) method and several test problems were solved. The results show that SCM can reduce the errors significantly both in multiplication factors and assembly averaged power distributions

Comparison of RF spectrum prediction methods for dynamic spectrum access

Science.gov (United States)

Kovarskiy, Jacob A.; Martone, Anthony F.; Gallagher, Kyle A.; Sherbondy, Kelly D.; Narayanan, Ram M.

2017-05-01

Dynamic spectrum access (DSA) refers to the adaptive utilization of today's busy electromagnetic spectrum. Cognitive radio/radar technologies require DSA to intelligently transmit and receive information in changing environments. Predicting radio frequency (RF) activity reduces sensing time and energy consumption for identifying usable spectrum. Typical spectrum prediction methods involve modeling spectral statistics with Hidden Markov Models (HMM) or various neural network structures. HMMs describe the time-varying state probabilities of Markov processes as a dynamic Bayesian network. Neural Networks model biological brain neuron connections to perform a wide range of complex and often non-linear computations. This work compares HMM, Multilayer Perceptron (MLP), and Recurrent Neural Network (RNN) algorithms and their ability to perform RF channel state prediction. Monte Carlo simulations on both measured and simulated spectrum data evaluate the performance of these algorithms. Generalizing spectrum occupancy as an alternating renewal process allows Poisson random variables to generate simulated data while energy detection determines the occupancy state of measured RF spectrum data for testing. The results suggest that neural networks achieve better prediction accuracy and prove more adaptable to changing spectral statistics than HMMs given sufficient training data.

Generation of equipment response spectrum considering equipment-structure interaction

International Nuclear Information System (INIS)

Lee, Sang Hoon; Yoo, Kwang Hoon

2005-01-01

Floor response spectra for dynamic response of subsystem such as equipment, or piping in nuclear power plant are usually generated without considering dynamic interaction between main structure and subsystem. Since the dynamic structural response generally has the narrow-banded shapes, the resulting floor response spectra developed for various locations in the structure usually have high spectral peak amplitudes in the narrow frequency bands corresponding to the natural frequencies of the structural system. The application of such spectra for design of subsystems often leads to excessive design conservatisms, especially when the equipment frequency and structure are at resonance condition. Thus, in order to provide a rational and realistic design input for dynamic analysis and design of equipment, dynamic equipment-structure interaction (ESI) should be considered in developing equipment response spectrum which is particularly important for equipment at the resonance condition. Many analytical methods have been proposed in the past for developing equipment response spectra considering ESI. However, most of these methods have not been adapted to the practical applications because of either the complexities or the lack of rigorousness of the methods. At one hand, mass ratio among the equipment and structure was used as an important parameter to obtain equipment response spectra. Similarly, Tseng has also proposed the analytical method for developing equipment response spectra using mass ratio in the frequency domain. This method is analytically rigorous and can be easily validated. It is based on the dynamic substructuring method as applied to the dynamic soil-structure interaction (SSI) analysis, and can relatively easily be implemented for practical applications without to change the current dynamic analysis and design practice for subsystems. The equipment response spectra derived in this study are also based on Tseng's proposed method

[A new measurement method of time-resolved spectrum].

Science.gov (United States)

Shi, Zhi-gang; Huang, Shi-hua; Liang, Chun-jun; Lei, Quan-sheng

2007-02-01

A new method for measuring time-resolved spectrum (TRS) is brought forward. Programming with assemble language controlled the micro-control-processor (AT89C51), and a kind of peripheral circuit constituted the drive circuit, which drived the stepping motor to run the monochromator. So the light of different kinds of expected wavelength could be obtained. The optical signal was transformed to electrical signal by optical-to-electrical transform with the help of photomultiplier tube (Hamamatsu 1P28). The electrical signal of spectrum data was transmitted to the oscillograph. Connecting the two serial interfaces of RS232 between the oscillograph and computer, the electrical signal of spectrum data could be transmitted to computer for programming to draw the attenuation curve and time-resolved spectrum (TRS) of the swatch. The method for measuring time-resolved spectrum (TRS) features parallel measurement in time scale but serial measurement in wavelength scale. Time-resolved spectrum (TRS) and integrated emission spectrum of Tb3+ in swatch Tb(o-BBA)3 phen were measured using this method. Compared with the real time-resolved spectrum (TRS). It was validated to be feasible, credible and convenient. The 3D spectra of fluorescence intensity-wavelength-time, and the integrated spectrum of the swatch Tb(o-BBA)3 phen are given.

Response margins investigation of piping dynamic analyses using the independent support motion method and PVRC [Pressure Vessel Research Committee] damping

International Nuclear Information System (INIS)

Bezler, P.; Wang, Y.K.; Reich, M.

1988-03-01

An evaluation of Independent Support Motion (ISM) response spectrum methods of analysis coupled with the Pressure Vessel Research Committee (PVRC) recommendation for damping, to compute the dynamic component of the seismic response of piping systems, was completed. Response estimates for five piping/structural systems were developed using fourteen variants of the ISM response spectrum method, the Uniform Support Motions response spectrum method and the ISM time history analysis method, all based on the PVRC recommendations for damping. The ISM/PVRC calculational procedures were found to exhibit orderly characteristics with levels of conservatism comparable to those obtained with the ISM/uniform damping procedures. Using the ISM/PVRC response spectrum method with absolute combination between group contributions provided consistently conservative results while using the ISM/PVRC response spectrum method with square root sum of squares combination between group contributions provided estimates of response which were deemed to be acceptable

The relationship between shock response spectrum and fast Fourier transform

International Nuclear Information System (INIS)

Zola, Maurizio

2001-01-01

In this paper the basic relationship between response spectrum and fast Fourier transform is laid down. Since a long time the response spectrum has been used by structural engineers in the seismic domain and nowadays it is going to be used to define transient motions. This way to define the excitation is more general and more real than the use of classical shape pulses for the reproduction of real environment. Nevertheless the response spectrum of a real excitation represents a loss of some information with respect to the Fourier transform. A useful discussion could arise from these observations. Appendix A gives the relationship between the mathematic Fourier transform and the digital Fourier transform given by computers, while Appendix B gives some examples of response spectra and Fourier transforms of simple functions. (author)

Analysis of soil-structure interaction and floor response spectrum of reactor building for China advanced research reactor

International Nuclear Information System (INIS)

Rong Feng; Wang Jiachun; He Shuyan

2006-01-01

Analysis of Soil-Structure Interaction (SSI) and calculation of Floor Response Spectrum (FRS) is substantial for anti-seismic design for China Advanced Research Reactor (CARR) project. The article uses direct method to analyze the seismic reaction of the reactor building in considering soil-structure interaction by establishing two-dimensional soil-structure co-acting model for analyzing and inputting of seismic waves from three directions respectively. The seismic response and floor response spectrum of foundation and floors of the building under different cases have been calculated. (authors)

Implicit Learning Abilities Predict Treatment Response in Autism Spectrum Disorders

Science.gov (United States)

2015-09-01

early behavioral interventions are the most effective treatment for Autism Spectrum Disorder (ASD), but almost half of the children do not make...behavioral intervention . 2. KEYWORDS Autism Spectrum Disorder , implicit learning, associative learning, individual differences, functional Magnetic...2 AWARD NUMBER: W81XWH-14-1-0261 TITLE: Implicit Learning Abilities Predict Treatment Response in Autism Spectrum Disorders PRINCIPAL

[A Method to Reconstruct Surface Reflectance Spectrum from Multispectral Image Based on Canopy Radiation Transfer Model].

Science.gov (United States)

Zhao, Yong-guang; Ma, Ling-ling; Li, Chuan-rong; Zhu, Xiao-hua; Tang, Ling-li

2015-07-01

Due to the lack of enough spectral bands for multi-spectral sensor, it is difficult to reconstruct surface retlectance spectrum from finite spectral information acquired by multi-spectral instrument. Here, taking into full account of the heterogeneity of pixel from remote sensing image, a method is proposed to simulate hyperspectral data from multispectral data based on canopy radiation transfer model. This method first assumes the mixed pixels contain two types of land cover, i.e., vegetation and soil. The sensitive parameters of Soil-Leaf-Canopy (SLC) model and a soil ratio factor were retrieved from multi-spectral data based on Look-Up Table (LUT) technology. Then, by combined with a soil ratio factor, all the parameters were input into the SLC model to simulate the surface reflectance spectrum from 400 to 2 400 nm. Taking Landsat Enhanced Thematic Mapper Plus (ETM+) image as reference image, the surface reflectance spectrum was simulated. The simulated reflectance spectrum revealed different feature information of different surface types. To test the performance of this method, the simulated reflectance spectrum was convolved with the Landsat ETM + spectral response curves and Moderate Resolution Imaging Spectrometer (MODIS) spectral response curves to obtain the simulated Landsat ETM+ and MODIS image. Finally, the simulated Landsat ETM+ and MODIS images were compared with the observed Landsat ETM+ and MODIS images. The results generally showed high correction coefficients (Landsat: 0.90-0.99, MODIS: 0.74-0.85) between most simulated bands and observed bands and indicated that the simulated reflectance spectrum was well simulated and reliable.

Research on influence of energy spectrum response of ICT detector arrays

International Nuclear Information System (INIS)

Zhou Rifeng; Gao Fuqiang; Zhang Ping

2008-01-01

The energy spectrum response is important characteristic for X-ray ICT detector. But there exist many difficulties to measure these parameters by experiments. The energy spectrum response of CdWO 4 detector was simulated by using the EGSnrc code. Meanwhile the effect of detection efficiency was analyzed by the distribution of accelerator bremsstrahlung spectra and the X-ray spectrum hardening, and some theoretic parameters were offered for the consistent and no-linearity correction of detector arrays. It was applied to ICT image correction, and a satisfying result was obtained. (authors)

Analytic moment method calculations of the drift wave spectrum

International Nuclear Information System (INIS)

Thayer, D.R.; Molvig, K.

1985-11-01

A derivation and approximate solution of renormalized mode coupling equations describing the turbulent drift wave spectrum is presented. Arguments are given which indicate that a weak turbulence formulation of the spectrum equations fails for a system with negative dissipation. The inadequacy of the weak turbulence theory is circumvented by utilizing a renormalized formation. An analytic moment method is developed to approximate the solution of the nonlinear spectrum integral equations. The solution method employs trial functions to reduce the integral equations to algebraic equations in basic parameters describing the spectrum. An approximate solution of the spectrum equations is first obtained for a mode dissipation with known solution, and second for an electron dissipation in the NSA

Impact induced response spectrum for the safety evaluation of the high flux isotope reactor

International Nuclear Information System (INIS)

Chang, S.J.

1997-01-01

The dynamic impact to the nearby HFIR reactor vessel caused by heavy load drop is analyzed. The impact calculation is carried out by applying the ABAQUS computer code. An impact-induced response spectrum is constructed in order to evaluate whether the HFIR vessel and the shutdown mechanism may be disabled. For the frequency range less than 10 Hz, the maximum spectral velocity of impact is approximately equal to that of the HFIR seismic design-basis spectrum. For the frequency range greater than 10 Hz, the impact-induced response spectrum is shown to cause no effect to the control rod and the shutdown mechanism. An earlier seismic safety assessment for the HFIR control and shutdown mechanism was made by EQE. Based on EQE modal solution that is combined with the impact-induced spectrum, it is concluded that the impact will not cause any damage to the shutdown mechanism, even while the reactor is in operation. The present method suggests a general approach for evaluating the impact induced damage to the reactor by applying the existing finite element modal solution that has been carried out for the seismic evaluation of the reactor

A method for measuring the energy spectrum of coincidence events in positron emission tomography.

Science.gov (United States)

Goertzen, Andrew L; Stout, David B; Thompson, Christopher J

2010-01-21

Positron emission tomography (PET) system energy response is typically characterized in singles detection mode, yet there are situations in which the energy spectrum of coincidence events might be different than the spectrum measured in singles mode. Examples include imaging with isotopes that emit a prompt gamma in coincidence with a positron emission, imaging with low activity in a LSO/LYSO-based cameras, in which the intrinsic activity is significant, and in high scatter situations where the two 511 keV photons have different scattering probabilities (i.e. off-center line source). The ability to accurately measure the energy spectrum of coincidence events could be used for validating simulation models, optimizing energy discriminator levels and examining scatter models and corrections. For many PET systems operating in coincidence mode, the only method available for estimating the energy spectrum is to step the lower and upper level discriminators (LLD and ULD). Simple measurement techniques such as using a narrow sliding energy window or stepping only the LLD will not yield a spectrum of coincidence events that is accurate for cases where there are different energy components contributing to the spectrum. In this work we propose a new method of measuring the energy spectrum of coincidence events in PET based on a linear combination of two sets of coincident count measurements: one made by stepping the LLD and one made by stepping the ULD. The method was tested using both Monte Carlo simulations of a Siemens microPET R4 camera and measured data acquired on a Siemens Inveon PET camera. The results show that our energy spectrum calculation method accurately measures the coincident energy spectra for cases including the beta/gamma spectrum of the (176)Lu intrinsic activity present in the LSO scintillator crystals, a (68)Ge source and an (124)I source (in which there are prompt gamma-rays emitted together with the positron).

A synthetic method of solar spectrum based on LED

Science.gov (United States)

Wang, Ji-qiang; Su, Shi; Zhang, Guo-yu; Zhang, Jian

2017-10-01

A synthetic method of solar spectrum which based on the spectral characteristics of the solar spectrum and LED, and the principle of arbitrary spectral synthesis was studied by using 14 kinds of LED with different central wavelengths.The LED and solar spectrum data were selected by Origin Software firstly, then calculated the total number of LED for each center band by the transformation relation between brightness and illumination and Least Squares Curve Fit in Matlab.Finally, the spectrum curve of AM1.5 standard solar spectrum was obtained. The results met the technical indexes of the solar spectrum matching with ±20% and the solar constant with >0.5.

Instantaneous response spectrum in seismic testing of nuclear power plant equipment

International Nuclear Information System (INIS)

Morrone, A.

1977-01-01

This paper presents the concept of instantaneous response spectrum (IRS) as the response of single degree of freedom oscillators at a particular time. It demonstrates that a shake table random motion whose standard TRS envelops the RRS does not necessarily satisfy the enveloping requirement instantaneously. That is, any one (or more) instantaneous required response spectrum (IRRS) is not enveloped by any instantaneous test response spectrum (ITRS). Response spectra from different time histories, including single frequency sine beat motion used in resonance testing, are compared for enveloping with maximum response and with the actual response at particular times. These comparisons are given for the enveloping of RRS and IRRS derived with a time history response calculated at a particular building elevation of a nuclear power plant. For the test motion, several of the most severe ITRS derived with a modified EL Centro motion and with a sine beat motion with ten cycles per beat were used. It is shown that although the TRS with the modified EL Centro motion enveloped the given RRS, the selected modified EL Centro ITRS did not envelop the corresponding IRRS. With the sine beat motion, even though the TRS did not fully envelop the given RRS, the resulting sine beat ITRS did not require a larger factor for full IRRS enveloping than those of the modified EL Centro motion

X-ray spectrum local method

International Nuclear Information System (INIS)

Avdonin, S.A.

1985-01-01

General characteristic and bases of X-ray spectrum local method used for qualitative and quantitative analyses of the mineral chemical composition with volumetric locality of several cubic micrometers. The method is based on the excitation in a sample of characteristic and bremsstrahlung spectra by means of a narrow electron beam at 5-50 keV accelerating voltage. Application of the method when studying uranium minerals and ores is considered. The method allows to determine the uranium presence forms in the ores, morphological features of the minerals, mineral microstructure, UO 2 and UO 3 ratios for unhydrous uraninites and pitchblendes and also to determine mineralization age

Evaluation of Floor Response Spectrum considering Ductility of Structure

Energy Technology Data Exchange (ETDEWEB)

Park, Junhee; Choi, In-Kil [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-10-15

The FRS (floor response spectrum) is directly influenced by the behavior of structure under the seismic load. If the structure is nonlinear range, the energy dissipation will be occurred by the damage of structure and the maximum force will be reduced. In Zion method, the inelastic energy abortion factor has been used to consider the nonlinearity of structure. This factor was used for the seismic fragility of structure. For the seismic fragility of equipment, the uncertainty of this factor was used differently according to the story level. But this method is not warranted under the strong earthquake leads to the structural damage. Therefore it is needed to evaluate the FRS considering the nonlinear behavior of structure and to assessment the conservatism related to nonlinear behavior of structure in FRS. In this study, the nonlinear analysis was performed for the conservatism of FRS under the damage of structure. The conservatism of FRS by the nonlinear analysis was compared by that proposed by the Zion method. The conservatism of floor acceleration response for the equipment was evaluated by performing the nonlinear analysis. From the nonlinear analysis results, it was showed that the median and β{sub c} of FRSR was increased with the ductility of structure and the response of equipment had the resonance effect between the frequency of equipment and structure. The seismic capacity of equipment by the Zion method can be different from the real seismic capacity of equipment because the inelastic structure response factor has nothing to do with the ductility of structure. Therefore the median and COV for FRSR should be defined considering the ductility of structure and the frequency of equipment for more exactly evaluating the seismic capacity of equipment.

Evaluation of Floor Response Spectrum considering Ductility of Structure

International Nuclear Information System (INIS)

Park, Junhee; Choi, In-Kil

2014-01-01

The FRS (floor response spectrum) is directly influenced by the behavior of structure under the seismic load. If the structure is nonlinear range, the energy dissipation will be occurred by the damage of structure and the maximum force will be reduced. In Zion method, the inelastic energy abortion factor has been used to consider the nonlinearity of structure. This factor was used for the seismic fragility of structure. For the seismic fragility of equipment, the uncertainty of this factor was used differently according to the story level. But this method is not warranted under the strong earthquake leads to the structural damage. Therefore it is needed to evaluate the FRS considering the nonlinear behavior of structure and to assessment the conservatism related to nonlinear behavior of structure in FRS. In this study, the nonlinear analysis was performed for the conservatism of FRS under the damage of structure. The conservatism of FRS by the nonlinear analysis was compared by that proposed by the Zion method. The conservatism of floor acceleration response for the equipment was evaluated by performing the nonlinear analysis. From the nonlinear analysis results, it was showed that the median and β c of FRSR was increased with the ductility of structure and the response of equipment had the resonance effect between the frequency of equipment and structure. The seismic capacity of equipment by the Zion method can be different from the real seismic capacity of equipment because the inelastic structure response factor has nothing to do with the ductility of structure. Therefore the median and COV for FRSR should be defined considering the ductility of structure and the frequency of equipment for more exactly evaluating the seismic capacity of equipment

A novel method of spectrum stabilization

International Nuclear Information System (INIS)

Sidhu, N.P.S.

1978-01-01

A new type of spectrum stabilizer for a scintillation spectrometer is described. A pulse light source DM 160 is used to introduce an artificial peak in the spectrum at a convenient energy. The centroid of pulse spectrum corresponding to artificial peak is compared with that of suitable reference pulses obtained from the DM 160 driver circuit. Any drift in artificial peak produces a d.c. voltage at the output of centroid comparator and this voltage is used to control the gain of variable gain amplifier to counter the drift. With suitable adjustment the effect of any variation in pulse height of DM 160 driving pulse can be compensated so that the spectrometer gain is independent of any variation, drift etc. in the height of pulse driving DM 160 tube. This circuit is simple and gives improved performance compared to 2 channel method of obtaining the control voltage for variable gain amplifier. (author)

A genetic algorithm based method for neutron spectrum unfolding

International Nuclear Information System (INIS)

Suman, Vitisha; Sarkar, P.K.

2013-03-01

An approach to neutron spectrum unfolding based on a stochastic evolutionary search mechanism - Genetic Algorithm (GA) is presented. It is tested to unfold a set of simulated spectra, the unfolded spectra is compared to the output of a standard code FERDOR. The method was then applied to a set of measured pulse height spectrum of neutrons from the AmBe source as well as of emitted neutrons from Li(p,n) and Ag(C,n) nuclear reactions carried out in the accelerator environment. The unfolded spectra compared to the output of FERDOR show good agreement in the case of AmBe spectra and Li(p,n) spectra. In the case of Ag(C,n) spectra GA method results in some fluctuations. Necessity of carrying out smoothening of the obtained solution is also studied, which leads to approximation of the solution yielding an appropriate solution finally. Few smoothing techniques like second difference smoothing, Monte Carlo averaging, combination of both and gaussian based smoothing methods are also studied. Unfolded results obtained after inclusion of the smoothening criteria are in close agreement with the output obtained from the FERDOR code. The present method is also tested on a set of underdetermined problems, the outputs of which is compared to the unfolded spectra obtained from the FERDOR applied to a completely determined problem, shows a good match. The distribution of the unfolded spectra is also studied. Uncertainty propagation in the unfolded spectra due to the errors present in the measurement as well as the response function is also carried out. The method appears to be promising for unfolding the completely determined as well as underdetermined problems. It also has provisions to carry out the uncertainty analysis. (author)

A fast computation method for MUSIC spectrum function based on circular arrays

Science.gov (United States)

Du, Zhengdong; Wei, Ping

2015-02-01

The large computation amount of multiple signal classification (MUSIC) spectrum function seriously affects the timeliness of direction finding system using MUSIC algorithm, especially in the two-dimensional directions of arrival (DOA) estimation of azimuth and elevation with a large antenna array. This paper proposes a fast computation method for MUSIC spectrum. It is suitable for any circular array. First, the circular array is transformed into a virtual uniform circular array, in the process of calculating MUSIC spectrum, for the cyclic characteristics of steering vector, the inner product in the calculation of spatial spectrum is realised by cyclic convolution. The computational amount of MUSIC spectrum is obviously less than that of the conventional method. It is a very practical way for MUSIC spectrum computation in circular arrays.

Libraries for spectrum identification: Method of normalized coordinates versus linear correlation

International Nuclear Information System (INIS)

Ferrero, A.; Lucena, P.; Herrera, R.G.; Dona, A.; Fernandez-Reyes, R.; Laserna, J.J.

2008-01-01

In this work it is proposed that an easy solution based directly on linear algebra in order to obtain the relation between a spectrum and a spectrum base. This solution is based on the algebraic determination of an unknown spectrum coordinates with respect to a spectral library base. The identification capacity comparison between this algebraic method and the linear correlation method has been shown using experimental spectra of polymers. Unlike the linear correlation (where the presence of impurities may decrease the discrimination capacity), this method allows to detect quantitatively the existence of a mixture of several substances in a sample and, consequently, to beer in mind impurities for improving the identification

Least-squares adjustment of a 'known' neutron spectrum: The importance of the covariance matrix of the input spectrum

International Nuclear Information System (INIS)

Mannhart, W.

1986-01-01

Based on the responses of 25 different neutron activation detectors, the neutron spectrum of Cf-252 hs been adjusted with least-squares methods. For a fixed input neutron spectrum, the covariance matrix of this spectrum has been systematically varied to investigate the influence of this matrix on the final result. The investigation showed that the adjusted neutron spectrum is rather sensitive to the structure of the covariance matrix for the input spectrum. (author)

Application of real time spectrum measurement to radiation monitors

International Nuclear Information System (INIS)

Matsuno, K.; Watanabe, M.; Sakamaki, T.

1996-01-01

A multichannel analyzer (MCA) and two realtime spectrum monitoring methods have been developed for use in radiation monitors. The new MCA was designed to be installed at a local site as a component of a radiation monitor. The MCA repeats spectrum measurement at short intervals (Δt) and, after each measurement, transmits a spectrum datum to the operation console. The authors applied two methods to process Δt spectrum counts for each channel for longer time interval. One method of processing counts is the 'running average (RA) method'. The other method is the 'exponential smoothing (ES) method', which simulates RC rate meters by subtracting a fraction corresponding to the accumulated counts. Relative standard deviations for each channel can be made the same by selecting an appropriate value. The response with the 'ES' method is initially faster than that with the 'RA' method, but the 'RA' method allows a full response to be reached at a predictable time. (author)

Short range spread-spectrum radiolocation system and method

Science.gov (United States)

Smith, Stephen F.

2003-04-29

A short range radiolocation system and associated methods that allow the location of an item, such as equipment, containers, pallets, vehicles, or personnel, within a defined area. A small, battery powered, self-contained tag is provided to an item to be located. The tag includes a spread-spectrum transmitter that transmits a spread-spectrum code and identification information. A plurality of receivers positioned about the area receive signals from a transmitting tag. The position of the tag, and hence the item, is located by triangulation. The system employs three different ranging techniques for providing coarse, intermediate, and fine spatial position resolution. Coarse positioning information is provided by use of direct-sequence code phase transmitted as a spread-spectrum signal. Intermediate positioning information is provided by the use of a difference signal transmitted with the direct-sequence spread-spectrum code. Fine positioning information is provided by use of carrier phase measurements. An algorithm is employed to combine the three data sets to provide accurate location measurements.

A note on probabilistic computation of earthquake response spectrum amplitudes

International Nuclear Information System (INIS)

Anderson, J.G.; Trifunac, M.D.

1979-01-01

This paper analyzes a method for computation of Pseudo Relative Velocity (PSV) spectrum and Absolute Acceleration (SA) spectrum so that the amplitudes and the shapes of these spectra reflect the geometrical characteristics of the seismic environment of the site. The estimated spectra also incorporate the geologic characteristics at the site, direction of ground motion and the probability of exceeding these motions. An example of applying this method in a realistic setting is presented and the uncertainties of the results are discussed. (Auth.)

Analysis of the computational methods on the equipment shock response based on ANSYS environments

International Nuclear Information System (INIS)

Wang Yu; Li Zhaojun

2005-01-01

With the developments and completions of equipment shock vibration theory, math calculation method simulation technique and other aspects, equipment shock calculation methods are gradually developing form static development to dynamic and from linearity to non-linearity. Now, the equipment shock calculation methods applied worldwide in engineering practices mostly include equivalent static force method, Dynamic Design Analysis Method (abbreviated to DDAM) and real-time simulation method. The DDAM is a method based on the modal analysis theory, which inputs the shock design spectrum as shock load and gets hold of the shock response of the integrated system by applying separate cross-modal integrating method within the frequency domain. The real-time simulation method is to carry through the computational analysis of the equipment shock response within the time domain, use the time-history curves obtained from real-time measurement or spectrum transformation as the equipment shock load and find an iterative solution of a differential equation of the system movement by using the computational procedure within the time domain. Conclusions: Using the separate DDAM and Real-time Simulation Method, this paper carried through the shock analysis of a three-dimensional frame floating raft in ANSYS environments, analyzed the result, and drew the following conclusion: Because DDAM does not calculate damping, non-linear effect and phase difference between mode responses, the result is much bigger than that of real-time simulation method. The coupling response is much complex when the mode result of 3-dimension structure is being calculated, and the coupling response of non-shock direction is also much bigger than that of real-time simulation method when DDAM is applied. Both DDAM and real-time simulation method has its good points and scope of application. The designers should select the design method that is economic and in point according to the features and anti

Statistical uncertainty of response characteristic of building-appendage system for spectrum-compatible artificial earthquake motion

International Nuclear Information System (INIS)

Kurosaki, A.; Kozeki, M.

1981-01-01

Spectrum-compatible artificial time histories of ground motions are frequently used for the seismic design of nuclear power plant structures and components. However, statistical uncertainty of the responses of building structures and mechanical components mounted on the building (building-appendage systems) are anticipated, since an artificial time history is no more than one sample from a population of such time histories that match a specified design response spectrum. This uncertainty may spoil the reliability of the seismic design and therefore the extent of the uncertainty of the response characteristic is a matter of great concern. In this paper, above-mentioned uncertainty of the dynamic response characteristics of the building-appendage system to the spectrum-compatible artificial earthquake is investigated. (orig./RW)

Method of detecting system function by measuring frequency response

Science.gov (United States)

Morrison, John L.; Morrison, William H.; Christophersen, Jon P.; Motloch, Chester G.

2013-01-08

Methods of rapidly measuring an impedance spectrum of an energy storage device in-situ over a limited number of logarithmically distributed frequencies are described. An energy storage device is excited with a known input signal, and a response is measured to ascertain the impedance spectrum. An excitation signal is a limited time duration sum-of-sines consisting of a select number of frequencies. In one embodiment, magnitude and phase of each frequency of interest within the sum-of-sines is identified when the selected frequencies and sample rate are logarithmic integer steps greater than two. This technique requires a measurement with a duration of one period of the lowest frequency. In another embodiment, where selected frequencies are distributed in octave steps, the impedance spectrum can be determined using a captured time record that is reduced to a half-period of the lowest frequency.

Method of T2 spectrum inversion with conjugate gradient algorithm from NMR data

International Nuclear Information System (INIS)

Li Pengju; Shi Shangming; Song Yanjie

2010-01-01

Based on the optimization techniques, the T 2 spectrum inversion method of conjugate gradient that is easy to realize non-negativity constraint of T2 spectrum is proposed. The method transforms the linear mixed-determined problem of T2 spectrum inversion into the typical optimization problem of searching the minimum of objective function by building up the objective function according to the basic idea of geophysics modeling. The optimization problem above is solved with the conjugate gradient algorithm that has quick convergence rate and quadratic termination. The method has been applied to the inversion of noise free echo train generated from artificial spectrum, artificial echo train with signal-to-noise ratio (SNR)=25 and NMR experimental data of drilling core. The comparison between the inversion results of this paper and artificial spectrum or the result of software imported in NMR laboratory shows that the method can correctly invert T 2 spectrum from artificial NMR relaxation data even though SNR=25 and that inversion T 2 spectrum with good continuity and smoothness from core NMR experimental data accords perfectly with that of laboratory software imported, and moreover,the absolute error between the NMR porosity computed from T 2 spectrum and helium (He) porosity in laboratory is 0.65%. (authors)

Spectrum scanning and reserve channel methods for link maintenance in cognitive radio systems

OpenAIRE

Subramani, S; Armour, SMD; Kaleshi, D; Fan, Z

2008-01-01

Underutilization of the limited spectrum sparked the need for dynamic spectrum access and flexible spectrum policies. Accurate estimation of spectrum occupancy is an essential step for spectrum access in distributed networks. This paper analyzes a bidirectional and dual scanning method that scans multiple spectrum bands to find a suitable free-channel. Moreover, secondary users' access to available spectrum could be interrupted by the arrival of primary spectrum users, forcing the well-behave...

Correction Method of Wiener Spectrum (WS) on Digital Medical Imaging Systems

International Nuclear Information System (INIS)

Kim, Jung Min; Lee, Ki Sung; Kim, You Hyun

2009-01-01

Noise evaluation for an image has been performed by root mean square (RMS) granularity, autocorrelation function (ACF), and Wiener spectrum. RMS granularity stands for standard deviation of photon data and ACF is acquired by integration of 1 D function of distance variation. Fourier transform of ACF results in noise power spectrum which is called Wiener spectrum in image quality evaluation. Wiener spectrum represents noise itself. In addition, along with MTF, it is an important factor to produce detective quantum efficiency (DQE). The proposed evaluation method using Wiener spectrum is expected to contribute to educate the concept of Wiener spectrum in educational organizations, choose the appropriate imaging detectors for clinical applications, and maintain image quality in digital imaging systems.

A BENCHMARK PROGRAM FOR EVALUATION OF METHODS FOR COMPUTING SEISMIC RESPONSE OF COUPLED BUILDING-PIPING/EQUIPMENT WITH NON-CLASSICAL DAMPING

International Nuclear Information System (INIS)

Xu, J.; Degrassi, G.; Chokshi, N.

2001-01-01

Under the auspices of the US Nuclear Regulatory Commission (NRC), Brookhaven National Laboratory (BNL) developed a comprehensive program to evaluate state-of-the-art methods and computer programs for seismic analysis of typical coupled nuclear power plant (NPP) systems with nonclassical damping. In this program, four benchmark models of coupled building-piping/equipment systems with different damping characteristics were analyzed for a suite of earthquakes by program participants applying their uniquely developed methods and computer programs. This paper presents the results of their analyses, and their comparison to the benchmark solutions generated by BNL using time domain direct integration methods. The participant's analysis results established using complex modal time history methods showed good comparison with the BNL solutions, while the analyses produced with either complex-mode response spectrum methods or classical normal-mode response spectrum method, in general, produced more conservative results, when averaged over a suite of earthquakes. However, when coupling due to damping is significant, complex-mode response spectrum methods performed better than the classical normal-mode response spectrum method. Furthermore, as part of the program objectives, a parametric assessment is also presented in this paper, aimed at evaluation of the applicability of various analysis methods to problems with different dynamic characteristics unique to coupled NPP systems. It is believed that the findings and insights learned from this program will be useful in developing new acceptance criteria and providing guidance for future regulatory activities involving licensing applications of these alternate methods to coupled systems

Comparative study for methods to determine the seismic response of NPP structures

International Nuclear Information System (INIS)

Varpasuo, P.

1995-01-01

There are many different important problem areas in evaluating the seismic response of structures. In this study the effort is concentrated on three of these areas. The first task is the mathematical formulation of earthquake excitation. The random vibration theory is taken as the tool in this task. The second area of interest in this study is the soil-structure interaction analysis. The approach of impedance functions is chosen and the focal point of interest is the significance of frequency dependent impedance functions. The third area of interest is the methods to determine the structural response. The following three methods were tested: the mode superposition time history method; the complex frequency response method; the response spectrum method. The comparison was made with the aid of MSC/NASTRAN code. The three methods gave for outer containment building response results which were in good agreement with each other. (author). 4 refs., 5 figs

A New Digital Signal Processing Method for Spectrum Interference Monitoring

Science.gov (United States)

Angrisani, L.; Capriglione, D.; Ferrigno, L.; Miele, G.

2011-01-01

Frequency spectrum is a limited shared resource, nowadays interested by an ever growing number of different applications. Generally, the companies providing such services pay to the governments the right of using a limited portion of the spectrum, consequently they would be assured that the licensed radio spectrum resource is not interested by significant external interferences. At the same time, they have to guarantee that their devices make an efficient use of the spectrum and meet the electromagnetic compatibility regulations. Therefore the competent authorities are called to control the access to the spectrum adopting suitable management and monitoring policies, as well as the manufacturers have to periodically verify the correct working of their apparatuses. Several measurement solutions are present on the market. They generally refer to real-time spectrum analyzers and measurement receivers. Both of them are characterized by good metrological accuracies but show costs, dimensions and weights that make no possible a use "on the field". The paper presents a first step in realizing a digital signal processing based measurement instrument able to suitably accomplish for the above mentioned needs. In particular the attention has been given to the DSP based measurement section of the instrument. To these aims an innovative measurement method for spectrum monitoring and management is proposed in this paper. It performs an efficient sequential analysis based on a sample by sample digital processing. Three main issues are in particular pursued: (i) measurement performance comparable to that exhibited by other methods proposed in literature; (ii) fast measurement time, (iii) easy implementation on cost-effective measurement hardware.

Spectrum unfolding by the least-squares methods

International Nuclear Information System (INIS)

Perey, F.G.

1977-01-01

The method of least squares is briefly reviewed, and the conditions under which it may be used are stated. From this analysis, a least-squares approach to the solution of the dosimetry neutron spectrum unfolding problem is introduced. The mathematical solution to this least-squares problem is derived from the general solution. The existence of this solution is analyzed in some detail. A chi 2 -test is derived for the consistency of the input data which does not require the solution to be obtained first. The fact that the problem is technically nonlinear, but should be treated in general as a linear one, is argued. Therefore, the solution should not be obtained by iteration. Two interpretations are made for the solution of the code STAY'SL, which solves this least-squares problem. The relationship of the solution to this least-squares problem to those obtained currently by other methods of solving the dosimetry neutron spectrum unfolding problem is extensively discussed. It is shown that the least-squares method does not require more input information than would be needed by current methods in order to estimate the uncertainties in their solutions. From this discussion it is concluded that the proposed least-squares method does provide the best complete solution, with uncertainties, to the problem as it is understood now. Finally, some implications of this method are mentioned regarding future work required in order to exploit its potential fully

Prediction of Support Reaction Forces of ITA via Response Spectrum Analysis

Energy Technology Data Exchange (ETDEWEB)

Kwak, Jin Sung; Jeong, Joon Ho; Lee, Sang Jin; Oh, Jin Ho; Lee, Jong Min [KAERI, Daejeon (Korea, Republic of)

2016-05-15

The irradiation targets are transferred along pipes between TTS (Target Transfer Station) and ITA (Irradiation Tube Assembly) by hydraulic forces. The ITA corresponds to the vertical guide tube for irradiation targets inside a reactor, and it penetrates the reactor structure. Because the ITA is classified into seismic category II, its structural integrity must be evaluated by the seismic analysis. To approach more realistic problem, the interaction between the ITA and the reactor structure must be considered. However, this paper is focused on the preliminary analysis, and it is simplified that only the response of the ITA caused by earthquake affects the reactor structure. The response of the ITA is predicted by the spectrum response analysis based on the FDRS (Floor Design Response Spectra) of KJRR. Finally, the reaction forces corresponding to the load transfer into the reactor structure are estimated by using ANSYS. In this study, the reaction forces due to the earthquake are estimated by the response spectrum analysis. For the saving computational time and resource required, the FE model with beam element is constructed, and it is confirmed that the accuracy of the solution is acceptable by comparing the results of the solid model.

Incremental-hinge piping analysis methods for inelastic seismic response prediction

International Nuclear Information System (INIS)

Jaquay, K.R.; Castle, W.R.; Larson, J.E.

1989-01-01

This paper proposes nonlinear seismic response prediction methods for nuclear piping systems based on simplified plastic hinge analyses. The simplified plastic hinge analyses utilize an incremental series of flat response spectrum loadings and replace yielded components with hinge elements when a predefined hinge moment is reached. These hinge moment values, developed by Rodabaugh, result in inelastic energy dissipation of the same magnitude as observed in seismic tests of piping components. Two definitions of design level equivalent loads are employed: one conservatively based on the peaks of the design acceleration response spectra, the other based on inelastic frequencies determined by the method of Krylov and Bogolyuboff recently extended by Lazzeri to piping. Both definitions account for piping system inelastic energy dissipation using Newmark-Hall inelastic response spectrum reduction factors and the displacement ductility results of the incremental-hinge analysis. Two ratchet-fatigue damage models are used: one developed by Rodabaugh that conservatively correlates Markl static fatigue expressions to seismic tests to failure of piping components; the other developed by Severud that uses the ratchet expression of Bree for elbows and Edmunds and Beer for straights, and defines ratchet-fatigue interaction using Coffin's ductility based fatigue equation. Comparisons of predicted behavior versus experimental results are provided for a high-level seismic test of a segment of a representative nuclear plant piping system. (orig.)

New Measurements and Calculations to Characterize the Caliban Pulsed Reactor Cavity Neutron Spectrum by the Foil Activation Method

Energy Technology Data Exchange (ETDEWEB)

Jacquet, X.; Casoli, P.; Authier, N.; Rousseau, G. [CEA, Centre de Valduc, 21120 Is-sur-Tille (France); Barsu, C. [Pl. de la fontaine, 25410 Corcelles-Ferrieres (France)

2011-07-01

Caliban is a cylindrical metallic core reactor mainly composed of uranium 235. It is operated by the Criticality and Neutron Science Research Laboratory located at the French Atomic Energy Commission research center in Valduc. As with other fast burst reactors, Caliban is used extensively for determining the responses of electronic parts or other objects and materials to neutron-induced displacements. Therefore, Caliban's irradiation characteristics, and especially its central cavity neutron spectrum, have to be very accurately evaluated. The foil activation method has been used in the past by the Criticality and Neutron Science Research Laboratory to evaluate the neutron spectrum of the different facilities it operated, and in particular to characterize the Caliban cavity spectrum. In order to strengthen and to improve our knowledge of the Caliban cavity neutron spectrum and to reduce the uncertainties associated with the available evaluations, new measurements have been performed on the reactor and interpreted by the foil activation method. A sensor set has been selected to sample adequately the studied spectrum. Experimental measured reaction rates have been compared to the results from UMG spectrum unfolding software and to values obtained with the activation code Fispact. Experimental and simulation results are overall in good agreement, although gaps exist for some sensors. UMG software has also been used to rebuild the Caliban cavity neutron spectrum from activation measurements. For this purpose, a default spectrum is needed, and one has been calculated with the Monte-Carlo transport code Tripoli 4 using the benchmarked Caliban description. (authors)

Efficient response spectrum analysis of a reactor using Model Order Reduction

International Nuclear Information System (INIS)

Oh, Jin Ho; Choi, Jin Bok; Ryu, Jeong Soo

2012-01-01

A response spectrum analysis (RSA) has been widely used to evaluate the structural integrity of various structural components in the nuclear industry. However, solving the large and complex structural systems numerically using the RSA requires a considerable amount of computational resources and time. To overcome this problem, this paper proposes the RSA based on the model order reduction (MOR) technique achieved by applying a projection from a higher order to a lower order space using Krylov subspaces generated by the Arnoldi algorithm. The dynamic characteristics of the final reduced system are almost identical with those of the full system by matching the moments of the reduced system with those of the full system up to the required nth order. It is remarkably efficient in terms of computation time and does not require a global system. Numerical examples demonstrate that the proposed method saves computational costs effectively, and provides a reduced system framework that predicts the accurate responses of a global system

Early Sensory Over-Responsivity in Toddlers with Autism Spectrum Disorders as a Predictor of Family Impairment and Parenting Stress

Science.gov (United States)

Ben-Sasson, A.; Soto, T. W.; Martinez-Pedraza, F.; Carter, A. S.

2013-01-01

Background: Sensory over-responsivity (SOR) affects many individuals with autism spectrum disorders (ASD), often leading to stressful encounters during daily routines. Methods: This study describes the associations between early SOR symptoms and the longitudinal course of restrictions in family life activities and parenting stress across three…

Tapering the sky response for angular power spectrum estimation from low-frequency radio-interferometric data.

Science.gov (United States)

Choudhuri, Samir; Bharadwaj, Somnath; Roy, Nirupam; Ghosh, Abhik; Ali, Sk Saiyad

2016-06-11

It is important to correctly subtract point sources from radio-interferometric data in order to measure the power spectrum of diffuse radiation like the Galactic synchrotron or the Epoch of Reionization 21-cm signal. It is computationally very expensive and challenging to image a very large area and accurately subtract all the point sources from the image. The problem is particularly severe at the sidelobes and the outer parts of the main lobe where the antenna response is highly frequency dependent and the calibration also differs from that of the phase centre. Here, we show that it is possible to overcome this problem by tapering the sky response. Using simulated 150 MHz observations, we demonstrate that it is possible to suppress the contribution due to point sources from the outer parts by using the Tapered Gridded Estimator to measure the angular power spectrum C ℓ of the sky signal. We also show from the simulation that this method can self-consistently compute the noise bias and accurately subtract it to provide an unbiased estimation of C ℓ .

[Research on the method of copper converting process determination based on emission spectrum analysis].

Science.gov (United States)

Li, Xian-xin; Liu, Wen-qing; Zhang, Yu-jun; Si, Fu-qi; Dou, Ke; Wang, Feng-ping; Huang, Shu-hua; Fang, Wu; Wang, Wei-qiang; Huang, Yong-feng

2012-05-01

A method of copper converting process determination based on PbO/PbS emission spectrum analysis was described. According to the known emission spectrum of gas molecules, the existence of PbO and PbS was confirmed in the measured spectrum. Through the field experiment it was determined that the main emission spectrum of the slag stage was from PbS, and the main emission spectrum of the copper stage was from PbO. The relative changes in PbO/PbS emission spectrum provide the method of copper converting process determination. Through using the relative intensity in PbO/PbS emission spectrum the copper smelting process can be divided into two different stages, i.e., the slag stage (S phase) and the copper stage (B phase). In a complete copper smelting cycle, a receiving telescope of appropriate view angle aiming at the converter flame, after noise filtering on the PbO/PbS emission spectrum, the process determination agrees with the actual production. Both the theory and experiment prove that the method of copper converting process determination based on emission spectrum analysis is feasible.

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

International Nuclear Information System (INIS)

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

2014-01-01

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

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

Science.gov (United States)

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

2014-12-01

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

Comparative study on γ-ray spectrum by several filtering method

International Nuclear Information System (INIS)

Yuan Xinyu; Liu Liangjun; Zhou Jianliang

2011-01-01

Comparative study was conducted on results of gamma-ray spectrum by using a majority of active smoothing method, which were used to show filtering effect. The results showed that peak was widened and overlap peaks increased with energy domain filter in γ-ray spectrum. Filter and its parameters should be seriously taken into consideration in frequency domain. Wavelet transformation can keep signal in high frequency region well. Improved threshold method showed the advantages of hard and soft threshold method at the same time by comparison, which was suitable for weak peaks detection. A new filter was put forward to eke out gravity model approach, whose denoise level was detected by standard deviation. This method not only kept signal and net area of peak well,but also attained better result and had simple computer program. (authors)

A Simple Method of Spectrum Processing for β-ray Measurement without Pretreatment

Energy Technology Data Exchange (ETDEWEB)

Bae, Jun Woo; Kim, Hee Reyoung [UNIST, Ulsan (Korea, Republic of)

2016-10-15

Radioactivity analysis of β-emitting radionuclide is important because of its dangerousness of overexposure. γ-ray has been measured by conventional detector such as NaI(Tl) or high purity germanium (HPGe) detector. But β-ray is hard to detect by those detectors because of its short range. Therefore, liquid scintillation counter (LSC) has been used to measure the radioactivity of pure beta emitter but there is huge problem of organic waste production, though LSC has high efficiency for detection of low energy β-ray. To solve this problem, characterization of β-ray measurement in a plastic scintillator was carried out in this study. There have been some studies about plastic scintillator to measure the β-rays without liquid scintillation method. Plastic scintillator has benefits for detection of β-ray because it has relative low effective atomic number. β-ray and γ-ray spectra in cylindrical plastic scintillator was analyzed and a method of separation of β-ray spectrum was suggested. A simple method of β-ray spectrum separation was suggested. The method was verified by chi-square method to estimate the difference between calculated and measured spectrum. This method was successfully applied by using disc source. For future works, practical radioactive source will be used to acquire the pulse height spectrum. The method can be used for measurement of pure β emitter without pretreatment if this method is verified for practical purpose.

239pu alpha spectrum analysis based on PIPS detector response function and variations with vacuum and distance

Institute of Scientific and Technical Information of China (English)

Rui Shi; Xian-Guo Tuo; Huai-Liang Li; Jian-Bo Yang; Yi Cheng; Hong-Long Zheng

2017-01-01

Effect factors of the absorption of the source,air,entrance window,and dead layer of a detector must be considered in the measurement of monoenergetic alpha particles,along with statsfical noise and other factors that collectively cause the alpha spectrum to exhibit a well-known low-energy tail.Therefore,the establishment of an alpha spectrum detector response function from the perspective of a signaling system must consider the various factors mentioned above.The detector response function is the convolution of an alphaparticle pulse function,two exponential functions,and a Gaussian function,followed by calculation of the parameters of the detector response function using the weighted leastsquares fitting method as proposed in this paper.In our experiment,239pu alpha spectra were measured by a highresolution,passivated implanted planar silicon (PIPS)detector at 10 levels of vacuum and 10 source-detector distances.The spectrum-fitting results were excellent as evaluated by reduced Chi-square (x2) and correlation coefficients.Finally,the variation of parameters with vacuum level and source-detector distance was studied.Results demonstrate that ο,τ1,and τ2 exhibit no obvious trend of variation with vacuum in the range 2000-20,000 mTorr,and at a confidence level of 95％,the values of τ1 and τ2 decline in a similar fashion with source-detector distance by the power exponential function,while the value of ο declines linearly.

Spectrum interrogation of fiber acoustic sensor based on self-fitting and differential method.

Science.gov (United States)

Fu, Xin; Lu, Ping; Ni, Wenjun; Liao, Hao; Wang, Shun; Liu, Deming; Zhang, Jiangshan

2017-02-20

In this article, we propose an interrogation method of fiber acoustic sensor to recover the time-domain signal from the sensor spectrum. The optical spectrum of the sensor will show a ripple waveform when responding to acoustic signal due to the scanning process in a certain wavelength range. The reason behind this phenomenon is the dynamic variation of the sensor spectrum while the intensity of different wavelength is acquired at different time in a scanning period. The frequency components can be extracted from the ripple spectrum assisted by the wavelength scanning speed. The signal is able to be recovered by differential between the ripple spectrum and its self-fitted curve. The differential process can eliminate the interference caused by environmental perturbations such as temperature or refractive index (RI), etc. The proposed method is appropriate for fiber acoustic sensors based on gratings or interferometers. A long period grating (LPG) is adopted as an acoustic sensor head to prove the feasibility of the interrogation method in experiment. The ability to compensate the environmental fluctuations is also demonstrated.

[Research on the temperature field detection method of hot forging based on long-wavelength infrared spectrum].

Science.gov (United States)

Zhang, Yu-Cun; Wei, Bin; Fu, Xian-Bin

2014-02-01

A temperature field detection method based on long-wavelength infrared spectrum for hot forging is proposed in the present paper. This method combines primary spectrum pyrometry and three-stage FP-cavity LCTF. By optimizing the solutions of three group nonlinear equations in the mathematical model of temperature detection, the errors are reduced, thus measuring results will be more objective and accurate. Then the system of three-stage FP-cavity LCTF was designed on the principle of crystal birefringence. The system realized rapid selection of any wavelength in a certain wavelength range. It makes the response of the temperature measuring system rapid and accurate. As a result, without the emissivity of hot forging, the method can acquire exact information of temperature field and effectively suppress the background light radiation around the hot forging and ambient light that impact the temperature detection accuracy. Finally, the results of MATLAB showed that the infrared spectroscopy through the three-stage FP-cavity LCTF could meet the requirements of design. And experiments verified the feasibility of temperature measuring method. Compared with traditional single-band thermal infrared imager, the accuracy of measuring result was improved.

SPECTRUM WEIGHTED RESPONSES OF SEVERAL DETECTORS IN MIXED FIELDS OF FAST AND THERMAL NEUTRONS

Directory of Open Access Journals (Sweden)

SANG IN KIM

2014-04-01

Full Text Available The spectrum weighted responses of various detectors were calculated to provide guidance on the proper selection and use of survey instruments on the basis of their energy response characteristics on the neutron fields. To yield the spectrum weighted response, the detector response functions of 17 neutron-measuring devices were numerically folded with each of the produced calibration neutron spectra through the in-house developed software ‘K-SWR’. The detectors’ response functions were taken from the IAEA Technical Reports Series No. 403 (TRS-403. The reference neutron fields of 21 kinds with 2 spectra groups with different proportions of thermal and fast neutrons have been produced using neutrons from the 241Am-Be sources held in a graphite pile, a bare 241Am-Be source, and a DT neutron generator. Fluence-average energy (Eave varied from 3.8 MeV to 16.9 MeV, and the ambient-dose-equivalent rate [H*(10/h] varied from 0.99 to 16.5 mSv/h.

An automatic method to determine cutoff frequency based on image power spectrum

International Nuclear Information System (INIS)

Beis, J.S.; Vancouver Hospital and Health Sciences Center, British Columbia; Celler, A.; Barney, J.S.

1995-01-01

The authors present an algorithm for automatically choosing filter cutoff frequency (F c ) using the power spectrum of the projections. The method is based on the assumption that the expectation of the image power spectrum is the sum of the expectation of the blurred object power spectrum (dominant at low frequencies) plus a constant value due to Poisson noise. By considering the discrete components of the noise-dominated high-frequency spectrum as a Gaussian distribution N(μ,σ), the Student t-test determines F c as the highest frequency for which the image frequency components are unlikely to be drawn from N (μ,σ). The method is general and can be applied to any filter. In this work, the authors tested the approach using the Metz restoration filter on simulated, phantom, and patient data with good results. Quantitative performance of the technique was evaluated by plotting recovery coefficient (RC) versus NMSE of reconstructed images

Pushover, Response Spectrum and Time History Analyses of Safe Rooms in a Poor Performance Masonry Building

International Nuclear Information System (INIS)

Mazloom, M.

2008-01-01

The idea of safe room has been developed for decreasing the earthquake casualties in masonry buildings. The information obtained from the previous ground motions occurring in seismic zones expresses the lack of enough safety of these buildings against earthquakes. For this reason, an attempt has been made to create some safe areas inside the existing masonry buildings, which are called safe rooms. The practical method for making these safe areas is to install some prefabricated steel frames in some parts of the existing structure. These frames do not carry any service loads before an earthquake. However, if a devastating earthquake happens and the load bearing walls of the building are destroyed, some parts of the floors, which are in the safe areas, will fall on the roof of the installed frames and the occupants who have sheltered there will survive. This paper presents the performance of these frames located in a destroying three storey masonry building with favorable conclusions. In fact, the experimental pushover diagram of the safe room located at the ground-floor level of this building is compared with the analytical results and it is concluded that pushover analysis is a good method for seismic performance evaluation of safe rooms. For time history analysis the 1940 El Centro, the 2003 Bam, and the 1990 Manjil earthquake records with the maximum peak accelerations of 0.35g were utilized. Also the design spectrum of Iranian Standard No. 2800-05 for the ground kind 2 is used for response spectrum analysis. The results of time history, response spectrum and pushover analyses show that the strength and displacement capacity of the steel frames are adequate to accommodate the distortions generated by seismic loads and aftershocks properly

A new method to cluster genomes based on cumulative Fourier power spectrum.

Science.gov (United States)

Dong, Rui; Zhu, Ziyue; Yin, Changchuan; He, Rong L; Yau, Stephen S-T

2018-06-20

Analyzing phylogenetic relationships using mathematical methods has always been of importance in bioinformatics. Quantitative research may interpret the raw biological data in a precise way. Multiple Sequence Alignment (MSA) is used frequently to analyze biological evolutions, but is very time-consuming. When the scale of data is large, alignment methods cannot finish calculation in reasonable time. Therefore, we present a new method using moments of cumulative Fourier power spectrum in clustering the DNA sequences. Each sequence is translated into a vector in Euclidean space. Distances between the vectors can reflect the relationships between sequences. The mapping between the spectra and moment vector is one-to-one, which means that no information is lost in the power spectra during the calculation. We cluster and classify several datasets including Influenza A, primates, and human rhinovirus (HRV) datasets to build up the phylogenetic trees. Results show that the new proposed cumulative Fourier power spectrum is much faster and more accurately than MSA and another alignment-free method known as k-mer. The research provides us new insights in the study of phylogeny, evolution, and efficient DNA comparison algorithms for large genomes. The computer programs of the cumulative Fourier power spectrum are available at GitHub (https://github.com/YaulabTsinghua/cumulative-Fourier-power-spectrum). Copyright © 2018. Published by Elsevier B.V.

A Method to Reconstruct the Solar-Induced Canopy Fluorescence Spectrum from Hyperspectral Measurements

Directory of Open Access Journals (Sweden)

Feng Zhao

2014-10-01

Full Text Available A method for canopy Fluorescence Spectrum Reconstruction (FSR is proposed in this study, which can be used to retrieve the solar-induced canopy fluorescence spectrum over the whole chlorophyll fluorescence emission region from 640–850 nm. Firstly, the radiance of the solar-induced chlorophyll fluorescence (Fs at five absorption lines of the solar spectrum was retrieved by a Spectral Fitting Method (SFM. The Singular Vector Decomposition (SVD technique was then used to extract three basis spectra from a training dataset simulated by the model SCOPE (Soil Canopy Observation, Photochemistry and Energy fluxes. Finally, these basis spectra were linearly combined to reconstruct the Fs spectrum, and the coefficients of them were determined by Weighted Linear Least Squares (WLLS fitting with the five retrieved Fs values. Results for simulated datasets indicate that the FSR method could accurately reconstruct the Fs spectra from hyperspectral measurements acquired by instruments of high Spectral Resolution (SR and Signal to Noise Ratio (SNR. The FSR method was also applied to an experimental dataset acquired in a diurnal experiment. The diurnal change of the reconstructed Fs spectra shows that the Fs radiance around noon was higher than that in the morning and afternoon, which is consistent with former studies. Finally, the potential and limitations of this method are discussed.

Seismic response analysis of structural system subjected to multiple support excitation

International Nuclear Information System (INIS)

Wu, R.W.; Hussain, F.A.; Liu, L.K.

1978-01-01

In the seismic analysis of a multiply supported structural system subjected to nonuniform excitations at each support point, the single response spectrum, the time history, and the multiple response spectrum are the three commonly employed methods. In the present paper the three methods are developed, evaluated, and the limitations and advantages of each method assessed. A numerical example has been carried out for a typical piping system. Considerably smaller responses have been predicted by the time history method than that by the single response spectrum method. This is mainly due to the fact that the phase and amplitude relations between the support excitations are faithfully retained in the time history method. The multiple response spectrum prediction has been observed to compare favourably with the time history method prediction. Based on the present evaluation, the multiple response spectrum method is the most efficient method for seismic response analysis of structural systems subjected to multiple support excitation. (Auth.)

Responsiveness of the Psychoeducational Profile-Third Edition for Children with Autism Spectrum Disorders

Science.gov (United States)

Chen, Kuan-Lin; Chiang, Fu-Mei; Tseng, Mei-Hui; Fu, Chung-Pei; Hsieh, Ching-Lin

2011-01-01

The aim of this study was to examine the responsiveness of the Psychoeducational Profile-third edition (PEP-3) in children with Autism Spectrum Disorders (ASD). We investigated the responsiveness in terms of three types of scores (i.e., raw scores, developmental ages, and percentile ranks) of the subtests and composites of the PEP-3 and three…

Systematic evaluations of probabilistic floor response spectrum generation

International Nuclear Information System (INIS)

Lilhanand, K.; Wing, D.W.; Tseng, W.S.

1985-01-01

The relative merits of the current methods for direct generation of probabilistic floor response spectra (FRS) from the prescribed design response spectra (DRS) are evaluated. The explicit probabilistic methods, which explicitly use the relationship between the power spectral density function (PSDF) and response spectra (RS), i.e., the PSDF-RS relationship, are found to have advantages for practical applications over the implicit methods. To evaluate the accuracy of the explicit methods, the root-mean-square (rms) response and the peak factor contained in the PSDF-RS relationship are systematically evaluated, especially for the narrow-band floor spectral response, by comparing the analytical results with simulation results. Based on the evaluation results, a method is recommended for practical use for the direct generation of probabilistic FRS. (orig.)

Planetary method to measure the neutrons spectrum in lineal accelerators of medical use

International Nuclear Information System (INIS)

Vega C, H. R.; Benites R, J. L.

2014-08-01

A novel procedure to measure the neutrons spectrum originated in a lineal accelerator of medical use has been developed. The method uses a passive spectrometer of Bonner spheres. The main advantage of the method is that only requires of a single shot of the accelerator. When this is used around a lineal accelerator is necessary to operate it under the same conditions so many times like the spheres that contain the spectrometer, activity that consumes enough time. The developed procedure consists on situating all the spheres of the spectrometer at the same time and to realize the reading making a single shot. With this method the photo neutrons spectrum produced by a lineal accelerator Varian ix of 15 MV to 100 cm of the isocenter was determined, with the spectrum is determined the total flow and the ambient dose equivalent. (Author)

Shock Protection of Portable Electronic Products: Shock Response Spectrum, Damage Boundary Approach, and Beyond

Directory of Open Access Journals (Sweden)

Suresh Goyal

1997-01-01

Full Text Available The pervasive shock response spectrum (SRS and damage boundary methods for evaluating product fragility and designing external cushioning for shock protection are described in detail with references to the best available literature. Underlying assumptions are carefully reviewed and the central message of the SRS is highlighted, particularly as it relates to standardized drop testing. Shortcomings of these methods are discussed, and the results are extended to apply to more general systems. Finally some general packaging and shock-mounting strategies are discussed in the context of protecting a fragile disk drive in a notebook computer, although the conclusions apply to other products as well. For example, exterior only cushioning (with low restitution to reduce subsequent impacts will provide a slenderer form factor than the next best strategy: interior cushioning with a “dead” hard outer shell.

Method of detecting system function by measuring frequency response

Science.gov (United States)

Morrison, John L [Butte, MT; Morrison, William H [Manchester, CT; Christophersen, Jon P [Idaho Falls, ID

2012-04-03

Real-time battery impedance spectrum is acquired using a one-time record. Fast Summation Transformation (FST) is a parallel method of acquiring a real-time battery impedance spectrum using a one-time record that enables battery diagnostics. An excitation current to a battery is a sum of equal amplitude sine waves of frequencies that are octave harmonics spread over a range of interest. A sample frequency is also octave and harmonically related to all frequencies in the sum. The time profile of this signal has a duration that is a few periods of the lowest frequency. The voltage response of the battery, average deleted, is the impedance of the battery in the time domain. Since the excitation frequencies are known and octave and harmonically related, a simple algorithm, FST, processes the time record by rectifying relative to the sine and cosine of each frequency. Another algorithm yields real and imaginary components for each frequency.

Neutron spectrum determination by activation method in fast neutron fields at the RB reactor

International Nuclear Information System (INIS)

Sokcic-Kostic, M.; Pesic, M.; Antic, D.

1994-01-01

The fast neutron fields of the RB reactor are presented in this paper. The activation method for spectrum determination is described and explained. The obtained results for intermediate and fast spectrum are given and discussed. (author)

Aquaporin-4 serostatus does not predict response to immunotherapy in neuromyelitis optica spectrum disorders.

Science.gov (United States)

Mealy, Maureen A; Kim, Su-Hyun; Schmidt, Felix; López, Reydmar; Jimenez Arango, Jorge A; Paul, Friedemann; Wingerchuk, Dean M; Greenberg, Benjamin M; Kim, Ho Jin; Levy, Michael

2017-08-01

Debate exists about whether neuromyelitis optica spectrum disorder seronegative disease represents the same immune-mediated attack on astrocytic aquaporin-4 as in seropositive disease. We investigated whether response to common treatments for neuromyelitis optica spectrum disorder differed by serostatus, as assessed by change in annualized relapse rate. We performed a multicenter retrospective analysis of 245 patients with neuromyelitis optica spectrum disorder who were treated with either rituximab or mycophenolate mofetil as their first-line immunosuppressive treatment for disease prevention. Patients were followed for a minimum of 6 months following treatment initiation. In those started on rituximab, the pre-treatment annualized relapse rates for seropositive and seronegative patients were 1.81 and 1.93, respectively. On-treatment annualized relapse rates significantly declined to 0.32 (seropositive; p optica spectrum disorder patients, treatment was effective regardless of serostatus. This suggests that treatment should not differ when considering these treatments.

A fully distributed method for dynamic spectrum sharing in femtocells

DEFF Research Database (Denmark)

Da Costa, Gustavo Wagner Oliveira; Cattoni, Andrea Fabio; Kovacs, Istvan

2012-01-01

such characteristics are combined the traditional network planning and optimization of cellular networks fails to be cost effective. Therefore, a greater deal of automation is needed in femtocells. In particular, this paper proposes a novel method for autonomous selection of spectrum/ channels in femtocells....... This method effectively mitigates cotier interference with no signaling at all across different femtocells. Still, the method has a remarkable simple implementation. The efficiency of the proposed method was evaluated by system level simulations. The results show large throughput gains for the cells...

[A method of recognizing biology surface spectrum using cascade-connection artificial neural nets].

Science.gov (United States)

Shi, Wei-Jie; Yao, Yong; Zhang, Tie-Qiang; Meng, Xian-Jiang

2008-05-01

A method of recognizing the visible spectrum of micro-areas on the biological surface with cascade-connection artificial neural nets is presented in the present paper. The visible spectra of spots on apples' pericarp, ranging from 500 to 730 nm, were obtained with a fiber-probe spectrometer, and a new spectrum recognition system consisting of three-level cascade-connection neural nets was set up. The experiments show that the spectra of rotten, scar and bumped spot on an apple's pericarp can be recognized by the spectrum recognition system, and the recognition accuracy is higher than 85% even when noise level is 15%. The new recognition system overcomes the disadvantages of poor accuracy and poor anti-noise with the traditional system based on single cascade neural nets. Finally, a new method of expression of recognition results was proved. The method is based on the conception of degree of membership in fuzzing mathematics, and through it the recognition results can be expressed exactly and objectively.

Quantitative Evaluation of gamma-Spectrum Analysis Methods using IAEA Test Spectra

DEFF Research Database (Denmark)

Nielsen, Sven Poul

1982-01-01

A description is given of a γ-spectrum analysis method based on nonlinear least-squares fitting. The quality of the method is investigated by using statistical tests on the results from analyses of IAEA test spectra. By applying an empirical correction factor of 0.75 to the calculated peak-area u...

[An automatic peak detection method for LIBS spectrum based on continuous wavelet transform].

Science.gov (United States)

Chen, Peng-Fei; Tian, Di; Qiao, Shu-Jun; Yang, Guang

2014-07-01

Spectrum peak detection in the laser-induced breakdown spectroscopy (LIBS) is an essential step, but the presence of background and noise seriously disturb the accuracy of peak position. The present paper proposed a method applied to automatic peak detection for LIBS spectrum in order to enhance the ability of overlapping peaks searching and adaptivity. We introduced the ridge peak detection method based on continuous wavelet transform to LIBS, and discussed the choice of the mother wavelet and optimized the scale factor and the shift factor. This method also improved the ridge peak detection method with a correcting ridge method. The experimental results show that compared with other peak detection methods (the direct comparison method, derivative method and ridge peak search method), our method had a significant advantage on the ability to distinguish overlapping peaks and the precision of peak detection, and could be be applied to data processing in LIBS.

Response of neural reward regions to food cues in autism spectrum disorders

Directory of Open Access Journals (Sweden)

Cascio Carissa J

2012-05-01

Full Text Available Abstract Background One hypothesis for the social deficits that characterize autism spectrum disorders (ASD is diminished neural reward response to social interaction and attachment. Prior research using established monetary reward paradigms as a test of non-social reward to compare with social reward may involve confounds in the ability of individuals with ASD to utilize symbolic representation of money and the abstraction required to interpret monetary gains. Thus, a useful addition to our understanding of neural reward circuitry in ASD includes a characterization of the neural response to primary rewards. Method We asked 17 children with ASD and 18 children without ASD to abstain from eating for at least four hours before an MRI scan in which they viewed images of high-calorie foods. We assessed the neural reward network for increases in the blood oxygenation level dependent (BOLD signal in response to the food images Results We found very similar patterns of increased BOLD signal to these images in the two groups; both groups showed increased BOLD signal in the bilateral amygdala, as well as in the nucleus accumbens, orbitofrontal cortex, and insula. Direct group comparisons revealed that the ASD group showed a stronger response to food cues in bilateral insula along the anterior-posterior gradient and in the anterior cingulate cortex than the control group, whereas there were no neural reward regions that showed higher activation for controls than for ASD. Conclusion These results suggest that neural response to primary rewards is not diminished but in fact shows an aberrant enhancement in children with ASD.

Neutron spectrum determination by activation method in fast neutron fields at the RB reactors

International Nuclear Information System (INIS)

Sokcic-Kostic, M.S.; Pesic, M.P.; Antic, D.P.

1994-01-01

The fast neutron fields of the RB reactor are presented in this paper. The activation method for spectrum determination is described and explained. The obtained results for intermediate and fast spectrum are given and discussed. (authors). 7 refs., 3 tabs

Photovoltaic yield: correction method for the mismatch between the solar spectrum and the reference ASTMG AM1.5G spectrum

Directory of Open Access Journals (Sweden)

Mambrini Thomas

2015-01-01

Full Text Available We propose a method for a spectral correction of the predicted PV yield and we show the importance of the spectral mismatch on the solar cell. Indeed, currently predicted PV yield are made considering solar irradiation, ambient temperature, incidence angle and partially (or not the solar spectrum. However, the solar spectrum is not always the same. It varies depending on the site location, atmospheric conditions, time of the day...This may impact the photovoltaic solar cells differently according to their technology (crystalline Silicon, thin film, multi-junctions... This paper presents a method for calculating the correction of the short-circuit current of a photovoltaic cell due to the mismatch of the solar spectrum with the reference ASTM AM1.5G spectrum, for a specific site, throughout the year, using monthly data of AERONET (AErosol RObotic NETwork established by NASA and CNRS and the model SMARTS (simple model for atmospheric transmission of sunshine developed by the NREL. We applied this correction method on the site of Palaiseau (France, 48.7°N, 2.2°E, 156 m, close to our laboratory, just for comparison and the example of Blida (Algeria, 36°N, 2°E, 230 m is given for one year. This example illustrates the importance of this spectral correction to better estimate the photovoltaic yield. To be more precise, instead of modeling the solar spectral distribution, one can measure it with a spectro-radiometer, and then, derive the spectral mismatch correction. Some of our typical measurements are presented in this paper.

Activation method for measurement of neutron spectrum parameters

International Nuclear Information System (INIS)

Efimov, B.V.; Demidov, A.M.; Ionov, V.S.; Konjaev, S.I.; Marin, S.V.; Bryzgalov, V.I.

2007-01-01

Experimental researches of spectrum parameters of neutrons at nuclear installations RRC KI are submitted. The installations have different designs of the cores, reflector, parameters and types of fuel elements. Measurements were carried out with use of the technique developed in RRC KI for irradiation resonance detectors UKD. The arrangement of detectors in the cores ensured possibility of measurement of neutron spectra with distinguished values of parameters. The spectrum parameters which are introduced by parametrical representation of a neutrons spectrum in the form corresponding to formalism Westcott. On experimental data were determinate absolute values of density neutron flux (DNF) in thermal and epithermal area of a spectrum (F t , f epi ), empirical dependence of temperature of neutron gas (Tn) on parameter of a rigidity of a spectrum (z), density neutron flux in transitional energy area of the spectrum. Dependences of spectral indexes of nuclides (UDy/UX), included in UKD, from a rigidity z and-or temperatures of neutron gas Tn are obtained.B Tools of mathematical processing of results are used for activation data and estimation of parameters of a spectrum (F t , f epi , z, Tn, UDy/UX). In the paper are presented some results of researches of neutron spectrum parameters of the nuclear installations (Authors)

Frequency characteristic measurement of a fiber optic gyroscope using a correlation spectrum analysis method based on a pseudo-random sequence

International Nuclear Information System (INIS)

Li, Yang; Chen, Xingfan; Liu, Cheng

2015-01-01

The frequency characteristic is an important indicator of a system’s dynamic performance. The identification of a fiber optic gyroscope (FOG)’s frequency characteristic using a correlation spectrum analysis method based on a pseudo-random sequence is proposed. Taking the angle vibrator as the source of the test rotation stimulation and a pseudo-random sequence as the test signal, the frequency characteristic of a FOG is calculated according to the power spectral density of the rotation rate signal and the cross-power spectral density of the FOG’s output signal and rotation rate signal. A theoretical simulation is done to confirm the validity of this method. An experiment system is built and the test results indicate that the measurement error of the normalized amplitude–frequency response is less than 0.01, that the error of the phase–frequency response is less than 0.3 rad, and the overall measurement accuracy is superior to the traditional frequency-sweep method. By using this method, the FOG’s amplitude–frequency response and phase–frequency response can be measured simultaneously, quickly, accurately, and with a high frequency resolution. The described method meets the requirements of engineering applications. (paper)

Analysis of a gamma-ray spectrum by using a standard spectrum

International Nuclear Information System (INIS)

Tasaka, Kanji

1975-06-01

The standard spectrum method has been extended to take into account the energy dependence of a standard spectrum. The method analyses the observed gamma-ray spectrum by the least-square method, using an interpolated standard spectrum for expressing the line shape and a linear function for the background continuum. The interpolated standard spectrum is defined for each fitting interval by interpolating several standard spectra, which are derived directly from the observed spectra of single photopeaks each corresponding to the incident monochromatic gamma-rays by subtracting the background and smoothing the data. (author)

Using activation method to measure neutron spectrum in an irradiation chamber of a research reactor

International Nuclear Information System (INIS)

Zhou Xuemei; Liu Guimin; Wang Xiaohe; Li Da; Meng Lingjie

2014-01-01

Neutron spectrum should be measured before test samples are irradiated. Neutron spectrum in an irradiation chamber of a research reactor was measured by using activation method when the reactor is in normal operation under 2 MW. Sixteen kinds of non-fission foils (19 reaction channels) were selected, of which 10 were sensitive to thermal and intermediate energy regions, while the others were of different threshold energy and sensitive to fast energy regions. By measuring the foil radioactivity, the neutron spectrum was unfolded with the iterative methods SAND-II and MSIT. Finally, shielding corrections of group cross-section and main factors affecting the calculation accuracy were studied and the uncertainty of solution was analyzed using the Monte Carlo method in the process of SAND-II. (authors)

Experimental validation of a structural damage detection method based on marginal Hilbert spectrum

Science.gov (United States)

Banerji, Srishti; Roy, Timir B.; Sabamehr, Ardalan; Bagchi, Ashutosh

2017-04-01

Structural Health Monitoring (SHM) using dynamic characteristics of structures is crucial for early damage detection. Damage detection can be performed by capturing and assessing structural responses. Instrumented structures are monitored by analyzing the responses recorded by deployed sensors in the form of signals. Signal processing is an important tool for the processing of the collected data to diagnose anomalies in structural behavior. The vibration signature of the structure varies with damage. In order to attain effective damage detection, preservation of non-linear and non-stationary features of real structural responses is important. Decomposition of the signals into Intrinsic Mode Functions (IMF) by Empirical Mode Decomposition (EMD) and application of Hilbert-Huang Transform (HHT) addresses the time-varying instantaneous properties of the structural response. The energy distribution among different vibration modes of the intact and damaged structure depicted by Marginal Hilbert Spectrum (MHS) detects location and severity of the damage. The present work investigates damage detection analytically and experimentally by employing MHS. The testing of this methodology for different damage scenarios of a frame structure resulted in its accurate damage identification. The sensitivity of Hilbert Spectral Analysis (HSA) is assessed with varying frequencies and damage locations by means of calculating Damage Indices (DI) from the Hilbert spectrum curves of the undamaged and damaged structures.

Research on n-γ discrimination method based on spectrum gradient analysis of signals

International Nuclear Information System (INIS)

Luo Xiaoliang; Liu Guofu; Yang Jun; Wang Yueke

2013-01-01

Having discovered that there are distinct differences between the spectrum gradient of the output neutron and γ-ray signal from liquid scintillator detectors, this paper presented a n-γ discrimination method called spectrum gradient analysis (SGA) based on frequency-domain features of the pulse signals. The basic principle and feasibility of SGA method were discussed and the validity of n-γ discrimination results of SGA was verified by the associated particle neutron flight experiment. The discrimination performance of SGA was evaluated under different conditions of sampling rates ranging from 5 G/s to 250 M/s. The results show that SGA method exhibits insensitivity to noise, strong anti-interference ability, stable discrimination performance and lower amount of calculation in contrast with time-domain n-γ discrimination methods. (authors)

Impaired Overt Facial Mimicry in Response to Dynamic Facial Expressions in High-Functioning Autism Spectrum Disorders

Science.gov (United States)

Yoshimura, Sayaka; Sato, Wataru; Uono, Shota; Toichi, Motomi

2015-01-01

Previous electromyographic studies have reported that individuals with autism spectrum disorders (ASD) exhibited atypical patterns of facial muscle activity in response to facial expression stimuli. However, whether such activity is expressed in visible facial mimicry remains unknown. To investigate this issue, we videotaped facial responses in…

Empathic responsiveness of children and adolescents with high-functioning autism spectrum disorder.

Science.gov (United States)

Scheeren, Anke M; Koot, Hans M; Mundy, Peter C; Mous, Larissa; Begeer, Sander

2013-10-01

Previous studies have shown reduced empathic responsiveness to others' emotions in preschoolers with autism spectrum disorder (ASD) and an intellectual disability. However, age and intelligence may promote children's empathic responsiveness. Therefore, we examined the empathic responsiveness in normally intelligent school-aged children and adolescents with a clinical diagnosis of ASD (n = 151) and in a typically developing comparison group (n = 50), using structured observations and parent reports. Based on the observations, participants' responses to the emotional displays of an interviewer were surprisingly similar. However, compared with parents from the comparison group, parents of a child with ASD reported significantly fewer empathic responses, particularly when the child received a high score on the Autism Diagnostic Observation Schedule. Even though parents report a reduced empathic responsiveness in school-aged children and adolescents with ASD, it may be difficult to find these empathic limitations during brief observations in a structured setting. © 2013 International Society for Autism Research, Wiley Periodicals, Inc.

A method for synthesizing response functions of NaI detectors to gamma rays

International Nuclear Information System (INIS)

Sie, S.H.

1978-08-01

A simple method of parametrizing the response function of NaI detectors to gamma rays is described, based on decomposition of the pulse-height spectrum into components associated with the actual detection processes. Smooth dependence of the derived parameters on the gamma-ray energy made it possible to generate a lineshape for any gamma-ray energy by suitable interpolation techniques. The method is applied in analysis of spectra measured with a 7.6 x 7.6 cm NaI detector in continuum gamma-ray study following (HI,xn) reaction

Spectrum correction algorithm for detectors in airborne radioactivity monitoring equipment NH-UAV based on a ratio processing method

International Nuclear Information System (INIS)

Cao, Ye; Tang, Xiao-Bin; Wang, Peng; Meng, Jia; Huang, Xi; Wen, Liang-Sheng; Chen, Da

2015-01-01

The unmanned aerial vehicle (UAV) radiation monitoring method plays an important role in nuclear accidents emergency. In this research, a spectrum correction algorithm about the UAV airborne radioactivity monitoring equipment NH-UAV was studied to measure the radioactive nuclides within a small area in real time and in a fixed place. The simulation spectra of the high-purity germanium (HPGe) detector and the lanthanum bromide (LaBr 3 ) detector in the equipment were obtained using the Monte Carlo technique. Spectrum correction coefficients were calculated after performing ratio processing techniques about the net peak areas between the double detectors on the detection spectrum of the LaBr 3 detector according to the accuracy of the detection spectrum of the HPGe detector. The relationship between the spectrum correction coefficient and the size of the source term was also investigated. A good linear relation exists between the spectrum correction coefficient and the corresponding energy (R 2 =0.9765). The maximum relative deviation from the real condition reduced from 1.65 to 0.035. The spectrum correction method was verified as feasible. - Highlights: • An airborne radioactivity monitoring equipment NH-UAV was developed to measure radionuclide after a nuclear accident. • A spectrum correction algorithm was proposed to obtain precise information on the detected radioactivity within a small area. • The spectrum correction method was verified as feasible. • The corresponding spectrum correction coefficients increase first and then stay constant

Spectrum correction algorithm for detectors in airborne radioactivity monitoring equipment NH-UAV based on a ratio processing method

Energy Technology Data Exchange (ETDEWEB)

Cao, Ye [Department of Nuclear Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Tang, Xiao-Bin, E-mail: tangxiaobin@nuaa.edu.cn [Department of Nuclear Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Jiangsu Key Laboratory of Nuclear Energy Equipment Materials Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Wang, Peng; Meng, Jia; Huang, Xi; Wen, Liang-Sheng [Department of Nuclear Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Chen, Da [Department of Nuclear Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Jiangsu Key Laboratory of Nuclear Energy Equipment Materials Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)

2015-10-11

The unmanned aerial vehicle (UAV) radiation monitoring method plays an important role in nuclear accidents emergency. In this research, a spectrum correction algorithm about the UAV airborne radioactivity monitoring equipment NH-UAV was studied to measure the radioactive nuclides within a small area in real time and in a fixed place. The simulation spectra of the high-purity germanium (HPGe) detector and the lanthanum bromide (LaBr{sub 3}) detector in the equipment were obtained using the Monte Carlo technique. Spectrum correction coefficients were calculated after performing ratio processing techniques about the net peak areas between the double detectors on the detection spectrum of the LaBr{sub 3} detector according to the accuracy of the detection spectrum of the HPGe detector. The relationship between the spectrum correction coefficient and the size of the source term was also investigated. A good linear relation exists between the spectrum correction coefficient and the corresponding energy (R{sup 2}=0.9765). The maximum relative deviation from the real condition reduced from 1.65 to 0.035. The spectrum correction method was verified as feasible. - Highlights: • An airborne radioactivity monitoring equipment NH-UAV was developed to measure radionuclide after a nuclear accident. • A spectrum correction algorithm was proposed to obtain precise information on the detected radioactivity within a small area. • The spectrum correction method was verified as feasible. • The corresponding spectrum correction coefficients increase first and then stay constant.

Evaluation of the Neutron Detector Response for Cosmic Ray Energy Spectrum by Monte Carlo Transport Simulation

International Nuclear Information System (INIS)

Pazianotto, Mauricio T.; Carlson, Brett V.; Federico, Claudio A.; Gonzalez, Odair L.

2011-01-01

Neutrons generated by the interaction of cosmic rays with the atmosphere make an important contribution to the dose accumulated in electronic circuits and aircraft crew members at flight altitude. High-energy neutrons are produced in spallation reactions and intranuclear cascade processes by primary cosmic-ray particle interactions with atoms in the atmosphere. These neutrons can produce secondary neutrons and also undergo a moderation process due to atmosphere interactions, resulting in a wider energy spectrum, ranging from thermal energies (0.025 eV) to energies of several hundreds of MeV. The Long-Counter (LC) detector is a widely used neutron detector designed to measure the directional flux of neutrons with about constant response over a wide energy range (thermal to 20 MeV). ). Its calibration process and the determination of its energy response for the wide-energy of cosmic ray induced neutron spectrum is a very difficult process due to the lack of installations with these capabilities. The goal of this study is to assess the behavior of the response of a Long Counter using the Monte Carlo (MC) computational code MCNPX (Monte Carlo N-Particle eXtended). The dependence of the Long Counter response on the angle of incidence, as well as on the neutron energy, will be carefully investigated, compared with the experimental data previously obtained with 241 Am-Be and 252 Cf neutron sources and extended to the neutron spectrum produced by cosmic rays. (Author)

Development of spectral history methods for pin-by-pin core analysis method using three-dimensional direct response matrix

International Nuclear Information System (INIS)

Mitsuyasu, T.; Ishii, K.; Hino, T.; Aoyama, M.

2009-01-01

Spectral history methods for pin-by-pin core analysis method using the three-dimensional direct response matrix have been developed. The direct response matrix is formalized by four sub-response matrices in order to respond to a core eigenvalue k and thus can be recomposed at each outer iteration in the core analysis. For core analysis, it is necessary to take into account the burn-up effect related to spectral history. One of the methods is to evaluate the nodal burn-up spectrum obtained using the out-going neutron current. The other is to correct the fuel rod neutron production rates obtained the pin-by-pin correction. These spectral history methods were tested in a heterogeneous system. The test results show that the neutron multiplication factor error can be reduced by half during burn-up, the nodal neutron production rates errors can be reduced by 30% or more. The root-mean-square differences between the relative fuel rod neutron production rate distributions can be reduced within 1.1% error. This means that these methods can accurately reflect the effects of intra- and inter-assembly heterogeneities during burn-up and can be used for core analysis. Core analysis with the DRM method was carried out for an ABWR quarter core and it was found that both thermal power and coolant-flow distributions were smoothly converged. (authors)

A simple method for the rapid assessment of the qualitative ESR response of fossil samples to laboratory irradiation

International Nuclear Information System (INIS)

Gruen, Rainer

2006-01-01

A simple and effective method is proposed for the analysis of the qualitative response of ESR spectra to dosing. The method comprises of the alignment of the spectra, and subtraction of the natural spectrum from those that were subsequently irradiated in the laboratory. In that way, the ESR response to environmental radiation can be compared to the ESR response to laboratory radiation. As illustrated on some tooth enamel and mollusk shell samples, both materials are frequently used in dating and accident dosimetry, the method is very effective for the identification of regions where the two radiation regimes generate qualitatively the same dose response as well as for the isolation of radiation insensitive signals that interfere with those used for dose estimation

Response Inhibition in Adults with Autism Spectrum Disorder Compared to Attention Deficit/Hyperactivity Disorder

Science.gov (United States)

Johnston, Kate; Madden, Anya K.; Bramham, Jessica; Russell, Ailsa J.

2011-01-01

Autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD) are hypothesised to involve core deficits in executive function. Previous studies have found evidence of a double dissociation between the disorders on specific executive functions (planning and response inhibition). To date most research has been conducted with…

Spectrum unfolding in X-ray spectrometry using the maximum entropy method

International Nuclear Information System (INIS)

Fernandez, Jorge E.; Scot, Viviana; Di Giulio, Eugenio

2014-01-01

The solution of the unfolding problem is an ever-present issue in X-ray spectrometry. The maximum entropy technique solves this problem by taking advantage of some known a priori physical information and by ensuring an outcome with only positive values. This method is implemented in MAXED (MAXimum Entropy Deconvolution), a software code contained in the package UMG (Unfolding with MAXED and GRAVEL) developed at PTB and distributed by NEA Data Bank. This package contains also the code GRAVEL (used to estimate the precision of the solution). This article introduces the new code UMESTRAT (Unfolding Maximum Entropy STRATegy) which applies a semi-automatic strategy to solve the unfolding problem by using a suitable combination of MAXED and GRAVEL for applications in X-ray spectrometry. Some examples of the use of UMESTRAT are shown, demonstrating its capability to remove detector artifacts from the measured spectrum consistently with the model used for the detector response function (DRF). - Highlights: ► A new strategy to solve the unfolding problem in X-ray spectrometry is presented. ► The presented strategy uses a suitable combination of the codes MAXED and GRAVEL. ► The applied strategy provides additional information on the Detector Response Function. ► The code UMESTRAT is developed to apply this new strategy in a semi-automatic mode

Unbroken Mirror Neurons in Autism Spectrum Disorders

Science.gov (United States)

Fan, Yang-Teng; Decety, Jean; Yang, Chia-Yen; Liu, Ji-Lin; Cheng, Yawei

2010-01-01

Background: The "broken mirror" theory of autism, which proposes that a dysfunction of the human mirror neuron system (MNS) is responsible for the core social and cognitive deficits in individuals with autism spectrum disorders (ASD), has received considerable attention despite weak empirical evidence. Methods: In this electroencephalographic…

Evaluation of methods used for the direct generation of response spectra

International Nuclear Information System (INIS)

Mayers, R.L.; Muraki, T.; Jones, L.R.; Donikian, R.

1983-01-01

The paper presents an alternate methodology by which seismic in-structure response spectra may be generated directly from either ground or floor excitation spectra. The method is based upon stochastic concepts and utilizes the modal superposition solution. The philosophy of the method is based upon the notion that the evaluation of 'peak' response in uncertain excitation environments is only meaningful in a probabilistic sense. This interpretation of response spectra facilitates the generation of in-structure spectra for any non-exceedance probability (NEP). The method is validated by comparisons with a set of deterministic time-history analyses with three example models: an eleven-story building model, a containment structure stick model, and a floor mounted control panel, subjected to ten input spectrum compatible acceleration time-histories. A significant finding resulting from these examples is that the time-history method portrayed substantial variation in the resulting in-structure spectra, and therefore is unreliable for the generation of spectra. It is shown that the average of the time-history generated spectra can be estimated by the direct generation procedure, and reliable spectra may be generated for 85 NEP levels. The methodology presented herein is shown to be valid for both primary and secondary systems. Also included in the paper, is a review of the stochastic methods proposed by Singh and Der Kiureghian et. al., and the Fourier transform method proposed by Scanlan et al. (orig./HP)

Phonon spectrum of YBCO obtained by specific heat inversion method for real data

CERN Document Server

Tao Wen; Dai Xian Xi; Dai Ji Xin; Evenson, W E

2003-01-01

In this paper, the phonon spectrum of YBCO is obtained from experimental specific heat data by an exact inversion formula with a parameter for eliminating divergences. The results can be compared to those of neutron inelastic scattering, which can only be carried out in a few laboratories. Some key points of specific heat-phonon spectrum inversion (SPI) theory and a method of asymptotic behaviour control are discussed. An improved unique existence theorem is presented, and a universal function set for numerical calculation of SPI is calculated with high accuracy, which makes the inversion method applicable and convenient in practice. This is the first time specific heat-phonon SPI has been realized for a concrete system.

Electromyographic Responses to Emotional Facial Expressions in 6-7 Year Olds with Autism Spectrum Disorders

Science.gov (United States)

Deschamps, P. K. H.; Coppes, L.; Kenemans, J. L.; Schutter, D. J. L. G.; Matthys, W.

2015-01-01

This study aimed to examine facial mimicry in 6-7 year old children with autism spectrum disorder (ASD) and to explore whether facial mimicry was related to the severity of impairment in social responsiveness. Facial electromyographic activity in response to angry, fearful, sad and happy facial expressions was recorded in twenty 6-7 year old…

Transient and steady-state auditory gamma-band responses in first-degree relatives of people with autism spectrum disorder

Directory of Open Access Journals (Sweden)

Rojas Donald C

2011-07-01

Full Text Available Abstract Background Stimulus-related γ-band oscillations, which may be related to perceptual binding, are reduced in people with autism spectrum disorders (ASD. The purpose of this study was to examine auditory transient and steady-state γ-band findings in first-degree relatives of people with ASD to assess the potential familiality of these findings in ASD. Methods Magnetoencephalography (MEG recordings in 21 parents who had a child with an autism spectrum disorder (pASD and 20 healthy adult control subjects (HC were obtained. Gamma-band phase locking factor (PLF, and evoked and induced power to 32, 40 and 48 Hz amplitude-modulated sounds were measured for transient and steady-state responses. Participants were also tested on a number of behavioral and cognitive assessments related to the broad autism phenotype (BAP. Results Reliable group differences were seen primarily for steady-state responses. In the left hemisphere, pASD subjects exhibited lower phase-locked steady-state power in all three conditions. Total γ-band power, including the non-phase-locked component, was also reduced in the pASD group. In addition, pASD subjects had significantly lower PLF than the HC group. Correlations were seen between MEG measures and BAP measures. Conclusions The reduction in steady-state γ-band responses in the pASD group is consistent with previous results for children with ASD. Steady-state responses may be more sensitive than transient responses to phase-locking errors in ASD. Together with the lower PLF and phase-locked power in first-degree relatives, correlations between γ-band measures and behavioral measures relevant to the BAP highlight the potential of γ-band deficits as a potential new autism endophenotype.

Response to unfairness across the suicide risk spectrum.

Science.gov (United States)

Carbajal, Jessica M; Gamboa, Jorge L; Moore, Jordan; Smith, Favrin; Ann Eads, Lou; Clothier, Jeffrey L; Cáceda, Ricardo

2017-12-01

Suicidal behavior is frequently triggered by social crises, such as familial, romantic, social or work-related conflict. A variety of cognitive and social functioning impairments has been associated with suicidal thoughts and acts. One of the precipitating and perpetuating factors of social conflict is the desire for retribution after a perceived offense, even at one's own detriment. We utilized the Ultimatum Game-a behavioral economic task which examines the behavioral response to perceived unfairness-in order to characterize the response to unfairness across the acute suicide risk spectrum. We examined five groups of adult individuals of both genders (n = 204): High- and Low-Lethality recent Suicide Attempters, Suicidal Ideators, Non-Suicidal Depressed Patients; and Healthy Controls. We also measured demographic and clinical variables. Even though all depressed groups showed similar rejection rates in the Ultimatum Game, there was a higher likelihood of rejecting offers in the low stakes condition in all acutely suicidal groups compared with healthy controls. Stake size, offer, education, and gender of the proposer were significantly associated with rejection rates. Acutely suicidal patients may be more vulnerable to adverse interpersonal interactions. Further characterization of social behavior may provide targets for secondary and tertiary prevention for high-risk individuals. Published by Elsevier B.V.

Assessment of precast beam-column using capacity demand response spectrum subject to design basis earthquake and maximum considered earthquake

Science.gov (United States)

Ghani, Kay Dora Abd.; Tukiar, Mohd Azuan; Hamid, Nor Hayati Abdul

2017-08-01

Malaysia is surrounded by the tectonic feature of the Sumatera area which consists of two seismically active inter-plate boundaries, namely the Indo-Australian and the Eurasian Plates on the west and the Philippine Plates on the east. Hence, Malaysia experiences tremors from far distant earthquake occurring in Banda Aceh, Nias Island, Padang and other parts of Sumatera Indonesia. In order to predict the safety of precast buildings in Malaysia under near field ground motion the response spectrum analysis could be used for dealing with future earthquake whose specific nature is unknown. This paper aimed to develop of capacity demand response spectrum subject to Design Basis Earthquake (DBE) and Maximum Considered Earthquake (MCE) in order to assess the performance of precast beam column joint. From the capacity-demand response spectrum analysis, it can be concluded that the precast beam-column joints would not survive when subjected to earthquake excitation with surface-wave magnitude, Mw, of more than 5.5 Scale Richter (Type 1 spectra). This means that the beam-column joint which was designed using the current code of practice (BS8110) would be severely damaged when subjected to high earthquake excitation. The capacity-demand response spectrum analysis also shows that the precast beam-column joints in the prototype studied would be severely damaged when subjected to Maximum Considered Earthquake (MCE) with PGA=0.22g having a surface-wave magnitude of more than 5.5 Scale Richter, or Type 1 spectra.

Neuroendocrine abnormalities in hypothalamic amenorrhea: spectrum, stability, and response to neurotransmitter modulation.

Science.gov (United States)

Perkins, R B; Hall, J E; Martin, K A

1999-06-01

To characterize the neuroendocrine patterns of abnormal GnRH secretion in hypothalamic amenorrhea (HA), 49 women with primary and secondary HA underwent frequent sampling of LH in a total of 72 baseline studies over 12-24 h. A subset of women participated in more than one study to address 1) the variability of LH pulse patterns over time; and 2) the impact of modulating opioid, dopaminergic, and adrenergic tone on LH secretory patterns. The frequency and amplitude of LH secretion was compared with that seen in the early follicular phase (EFP) of normally cycling women. The spectrum of abnormalities of LH pulses was 8% apulsatile, 27% low frequency/low amplitude, 8% low amplitude/normal frequency, 43% low frequency/normal amplitude, 14% normal frequency/normal amplitude. Of patients studied overnight, 45% demonstrated a pubertal pattern of augmented LH secretion during sleep. Of patients studied repeatedly, 75% demonstrated at least 2 different patterns of LH secretion, and 33% reverted at least once to a normal pattern of secretion. An increase in LH pulse frequency was seen in 12 of 15 subjects in response to naloxone (opioid receptor antagonist). Clonidine (alpha-2 adrenergic agonist) was associated with a decrease in mean LH in 3 of 3 subjects. An increase in LH pulse frequency was seen in 4 of 8 subjects in response to metoclopramide (dopamine receptor antagonist), but the response was not statistically significant. Baseline abnormalities in LH secretion did not appear to influence response to neurotransmitter modulation. 1) HA represents a spectrum of disordered GnRH secretion that can vary over time; 2) LH pulse patterns at baseline do not appear to influence the ability to respond to neurotransmitter modulation; 3) Opioid and adrenergic tone appear to influence the hypothalamic GnRH pulse generator in some individuals with HA.

Measurement of Neutron Energy Spectrum Emitted by Cf-252 Source Using Time-of-Flight Method

Energy Technology Data Exchange (ETDEWEB)

Lee, Cheol Ho; Son, Jaebum; Kim, Tae Hoon; Lee, Sangmin; Kim, Yong-Kyun [Hanyang University, Seoul (Korea, Republic of)

2016-10-15

The techniques proposed to detect the neutrons usually require the detection of a secondary recoiling nucleus in a scintillator (or other type of detector) to indicate the rare collision of a neutron with a nucleus. This is the same basic technique, in this case detection of a recoil proton that was used by Chadwick in the 1930 s to discover and identify the neutron and determine its mass. It is primary technique still used today for detection of fast neutron, which typically involves the use of a hydrogen based organic plastic or liquid scintillator coupled to a photo-multiplier tube. The light output from such scintillators is a function of the cross section and nuclear kinematics of the n + nucleus collision. With the exception of deuterated scintillators, the scintillator signal does not necessarily produce a distinct peak in the scintillator spectrum directly related to the incident neutron energy. Instead neutron time-of-flight (TOF) often must be utilized to determine the neutron energy, which requires generation of a prompt start signal from the nuclear source emitting the neutrons. This method takes advantage of the high number of prompt gamma rays. The Time-of-Flight method was used to measure neutron energy spectrum emitted by the Cf-252 neutron source. Plastic scintillator that has a superior discrimination ability of neutron and gamma-ray was used as a stop signal detector and liquid scintillator was used as a stat signal detector. In experiment, neutron and gamma-ray spectrum was firstly measured and discriminated using the TOF method. Secondly, neutron energy spectrum was obtained through spectrum analysis. Equation of neutron energy spectrum that was emitted by Cf-252 source using the Gaussian fitting was obtained.

Radioisotope identification method for poorly resolved gamma-ray spectrum of nuclear security concern

Energy Technology Data Exchange (ETDEWEB)

Ninh, Giang Nguyen; Phongphaeth, Pengvanich, E-mail: phongphaeth.p@chula.ac.th; Nares, Chankow [Nuclear Engineering Department, Faculty of Engineering, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330 (Thailand); Hao, Quang Nguyen [Vietnam Atomic Energy Institute, Ministry of Science and Technology, Hanoi (Viet Nam)

2016-01-22

Gamma-ray signal can be used as a fingerprint for radioisotope identification. In the context of radioactive and nuclear materials security at the border control point, the detection task can present a significant challenge due to various constraints such as the limited measurement time, the shielding conditions, and the noise interference. This study proposes a novel method to identify the signal of one or several radioisotopes from a poorly resolved gamma-ray spectrum. In this method, the noise component in the raw spectrum is reduced by the wavelet decomposition approach, and the removal of the continuum background is performed using the baseline determination algorithm. Finally, the identification of radioisotope is completed using the matrix linear regression method. The proposed method has been verified by experiments using the poorly resolved gamma-ray signals from various scenarios including single source, mixing of natural uranium with five of the most common industrial radioactive sources (57Co, 60Co, 133Ba, 137Cs, and 241Am). The preliminary results show that the proposed algorithm is comparable with the commercial method.

Radioisotope identification method for poorly resolved gamma-ray spectrum of nuclear security concern

International Nuclear Information System (INIS)

Ninh, Giang Nguyen; Phongphaeth, Pengvanich; Nares, Chankow; Hao, Quang Nguyen

2016-01-01

Gamma-ray signal can be used as a fingerprint for radioisotope identification. In the context of radioactive and nuclear materials security at the border control point, the detection task can present a significant challenge due to various constraints such as the limited measurement time, the shielding conditions, and the noise interference. This study proposes a novel method to identify the signal of one or several radioisotopes from a poorly resolved gamma-ray spectrum. In this method, the noise component in the raw spectrum is reduced by the wavelet decomposition approach, and the removal of the continuum background is performed using the baseline determination algorithm. Finally, the identification of radioisotope is completed using the matrix linear regression method. The proposed method has been verified by experiments using the poorly resolved gamma-ray signals from various scenarios including single source, mixing of natural uranium with five of the most common industrial radioactive sources (57Co, 60Co, 133Ba, 137Cs, and 241Am). The preliminary results show that the proposed algorithm is comparable with the commercial method

Functional Neuroimaging of Sensory Over-Responsivity in Youth With Autism Spectrum Disorders

OpenAIRE

Green, Shulamite A.

2014-01-01

In addition to the core social and communication symptoms, individuals with autism spectrum disorders (ASD) have high rates of sensory over-responsivity (SOR). Despite the fact that over half of children and adolescents with ASD have SOR, very little is known about the neurobiological bases of this condition. SOR often co-occurs with anxiety disorders, which suggests a possible common biological basis for both SOR and anxiety in a subgroup of youth with ASD. The following studies used functio...

Floor response spectra for multi-degree-of-freedom systems by Fourier transform

International Nuclear Information System (INIS)

Scanlan, R.H.; Sachs, K.

1975-01-01

A method of generating floor response spectra from a given ground response spectrum is given. This time-saving approach makes use of Fourier spectrum techniques and the randomness of phase angles. In matrix form a structure having many degrees-of-freedom is described by the equation of motion with M, C, K as the mass-, damping-, and stiffness matrices and Z being the acceleration time history of the earthquake and I a direction vector. If the Fourier spectrum FZ of the ground motion is known, then by standard methods the Fourier spectrum of the equipment response can be obtained. The assumption of random phase angles for the synthetic time history Z seems reasonable. The response is then also a superposition of cosine waves. Good agreement with time history methods is obtained. This method is much faster than time history methods, which are being used in most applications

New method of interpretation of the solar spectrum lines

International Nuclear Information System (INIS)

Sitnik, G.F.

1975-01-01

Close triplet lines, which appear from a common low level or from low sublevels with small energy difference are used. It is supposed that for such lines both the function of the source in line and the frequency dependence of the selective coefficient of absorption are the same over any depth of the region of line production in the atmosphere and change with the depth equally. The residual intensities of some lines of the triplet, which are measured for every line at a number of profile points (at the same distance from its center and at different distances from the solar limb center), serve as initial material. The intensities are expressed in terms of the intensity of the continuous spectrum in the center of the solar limb for the average wave length of the triplet interval. Such observations avoid the usual assumption about the source function constancy in line inside the line. On the contrary, the frequency dependence of this function is clarified by the use of this method. Calculations make it possible to determine the source function in line and its long-wave dependence inside the line; to derive a solar atmosphere model and to determine the source function in the continuous spectrum in accordance with observations at profile points in its middle part and in the wing; to find the relation between the selective and continuous absorption coefficients in the dependence on the optical depth in the continuous spectrum; and to find the long-wave dependences of coefficients for both the selective absorption and the selective emission at different optical depths

Synthesis of artificial spectrum-compatible seismic accelerograms

International Nuclear Information System (INIS)

Vrochidou, E; Alvanitopoulos, P F; Andreadis, I; Mallousi, K; Elenas, A

2014-01-01

The Hilbert–Huang transform is used to generate artificial seismic signals compatible with the acceleration spectra of natural seismic records. Artificial spectrum-compatible accelerograms are utilized instead of natural earthquake records for the dynamic response analysis of many critical structures such as hospitals, bridges, and power plants. The realistic estimation of the seismic response of structures involves nonlinear dynamic analysis. Moreover, it requires seismic accelerograms representative of the actual ground acceleration time histories expected at the site of interest. Unfortunately, not many actual records of different seismic intensities are available for many regions. In addition, a large number of seismic accelerograms are required to perform a series of nonlinear dynamic analyses for a reliable statistical investigation of the structural behavior under earthquake excitation. These are the main motivations for generating artificial spectrum-compatible seismic accelerograms and could be useful in earthquake engineering for dynamic analysis and design of buildings. According to the proposed method, a single natural earthquake record is deconstructed into amplitude and frequency components using the Hilbert–Huang transform. The proposed method is illustrated by studying 20 natural seismic records with different characteristics such as different frequency content, amplitude, and duration. Experimental results reveal the efficiency of the proposed method in comparison with well-established and industrial methods in the literature. (paper)

Associations between cytokines, endocrine stress response, and gastrointestinal symptoms in autism spectrum disorder

OpenAIRE

Ferguson, Bradley J.; Marler, Sarah; Altstein, Lily L.; Lee, Evon Batey; Mazurek, Micah O.; McLaughlin, Aaron; Macklin, Eric A.; McDonnell, Erin; Davis, Daniel J.; Belenchia, Anthony M.; Gillespie, Catherine H.; Peterson, Catherine A.; Bauman, Margaret L.; Margolis, Kara Gross; Veenstra-VanderWeele, Jeremy

2016-01-01

Many children and adolescents with autism spectrum disorder (ASD) have significant gastrointestinal (GI) symptoms, but the etiology is currently unknown. Some individuals with ASD show altered reactivity to stress and altered immune markers relative to typically-developing individuals, particularly stress-responsive cytokines including tumor necrosis factor alpha (TNF-?) and interleukin 6 (IL-6). Acute and chronic stress is associated with the onset and exacerbation of GI symptoms in those wi...

Local region power spectrum-based unfocused ship detection method in synthetic aperture radar images

Science.gov (United States)

Wei, Xiangfei; Wang, Xiaoqing; Chong, Jinsong

2018-01-01

Ships on synthetic aperture radar (SAR) images will be severely defocused and their energy will disperse into numerous resolution cells under long SAR integration time. Therefore, the image intensity of ships is weak and sometimes even overwhelmed by sea clutter on SAR image. Consequently, it is hard to detect the ships from SAR intensity images. A ship detection method based on local region power spectrum of SAR complex image is proposed. Although the energies of the ships are dispersed on SAR intensity images, their spectral energies are rather concentrated or will cause the power spectra of local areas of SAR images to deviate from that of sea surface background. Therefore, the key idea of the proposed method is to detect ships via the power spectra distortion of local areas of SAR images. The local region power spectrum of a moving target on SAR image is analyzed and the way to obtain the detection threshold through the probability density function (pdf) of the power spectrum is illustrated. Numerical P- and L-band airborne SAR ocean data are utilized and the detection results are also illustrated. Results show that the proposed method can well detect the unfocused ships, with a detection rate of 93.6% and a false-alarm rate of 8.6%. Moreover, by comparing with some other algorithms, it indicates that the proposed method performs better under long SAR integration time. Finally, the applicability of the proposed method and the way of parameters selection are also discussed.

Minimally verbal school-aged children with autism spectrum disorder: the neglected end of the spectrum.

Science.gov (United States)

Tager-Flusberg, Helen; Kasari, Connie

2013-12-01

It is currently estimated that about 30% of children with autism spectrum disorder remain minimally verbal, even after receiving years of interventions and a range of educational opportunities. Very little is known about the individuals at this end of the autism spectrum, in part because this is a highly variable population with no single set of defining characteristics or patterns of skills or deficits, and in part because it is extremely challenging to provide reliable or valid assessments of their developmental functioning. In this paper, we summarize current knowledge based on research including minimally verbal children. We review promising new novel methods for assessing the verbal and nonverbal abilities of minimally verbal school-aged children, including eye-tracking and brain-imaging methods that do not require overt responses. We then review what is known about interventions that may be effective in improving language and communication skills, including discussion of both nonaugmentative and augmentative methods. In the final section of the paper, we discuss the gaps in the literature and needs for future research. © 2013 International Society for Autism Research, Wiley Periodicals, Inc.

Converging Pathways in Autism Spectrum Disorders: Interplay Between Synaptic Dysfunction and Immune Responses

Directory of Open Access Journals (Sweden)

Irina eVoineagu

2013-11-01

Full Text Available Autism spectrum disorders (ASD are highly heritable, yet genetically heterogeneous neurodevelopmental conditions. Recent genome-wide association and gene expression studies have provided evidence supporting the notion that the large number of genetic variants associated with ASD converge toward a core set of dysregulated biological processes. Here we review recent data demonstrating the involvement of synaptic dysfunction and abnormal immune responses in ASD, and discuss the functional interplay between the two phenomena.

Spectrum Recombination.

Science.gov (United States)

Greenslade, Thomas B., Jr.

1984-01-01

Describes several methods of executing lecture demonstrations involving the recombination of the spectrum. Groups the techniques into two general classes: bringing selected portions of the spectrum together using lenses or mirrors and blurring the colors by rapid movement or foreshortening. (JM)

Influence of the Spatial Dimensions of Ultrasonic Transducers on the Frequency Spectrum of Guided Waves.

Science.gov (United States)

Samaitis, Vykintas; Mažeika, Liudas

2017-08-08

Ultrasonic guided wave (UGW)-based condition monitoring has shown great promise in detecting, localizing, and characterizing damage in complex systems. However, the application of guided waves for damage detection is challenging due to the existence of multiple modes and dispersion. This results in distorted wave packets with limited resolution and the interference of multiple reflected modes. To develop reliable inspection systems, either the transducers have to be optimized to generate a desired single mode of guided waves with known dispersive properties, or the frequency responses of all modes present in the structure must be known to predict wave interaction. Currently, there is a lack of methods to predict the response spectrum of guided wave modes, especially in cases when multiple modes are being excited simultaneously. Such methods are of vital importance for further understanding wave propagation within the structures as well as wave-damage interaction. In this study, a novel method to predict the response spectrum of guided wave modes was proposed based on Fourier analysis of the particle velocity distribution on the excitation area. The method proposed in this study estimates an excitability function based on the spatial dimensions of the transducer, type of vibration, and dispersive properties of the medium. As a result, the response amplitude as a function of frequency for each guided wave mode present in the structure can be separately obtained. The method was validated with numerical simulations on the aluminum and glass fiber composite samples. The key findings showed that it can be applied to estimate the response spectrum of a guided wave mode on any type of material (either isotropic structures, or multi layered anisotropic composites) and under any type of excitation if the phase velocity dispersion curve and the particle velocity distribution of the wave source was known initially. Thus, the proposed method may be a beneficial tool to explain

Neuromagnetic Oscillations Predict Evoked-Response Latency Delays and Core Language Deficits in Autism Spectrum Disorders

Science.gov (United States)

Edgar, J. Christopher; Khan, Sarah Y.; Blaskey, Lisa; Chow, Vivian Y.; Rey, Michael; Gaetz, William; Cannon, Katelyn M.; Monroe, Justin F.; Cornew, Lauren; Qasmieh, Saba; Liu, Song; Welsh, John P.; Levy, Susan E.; Roberts, Timothy P. L.

2015-01-01

Previous studies have observed evoked response latency as well as gamma band superior temporal gyrus (STG) auditory abnormalities in individuals with autism spectrum disorders (ASD). A limitation of these studies is that associations between these two abnormalities, as well as the full extent of oscillatory phenomena in ASD in terms of frequency…

Band selection method based on spectrum difference in targets of interest in hyperspectral imagery

Science.gov (United States)

Zhang, Xiaohan; Yang, Guang; Yang, Yongbo; Huang, Junhua

2016-10-01

While hyperspectral data shares rich spectrum information, it has numbers of bands with high correlation coefficients, causing great data redundancy. A reasonable band selection is important for subsequent processing. Bands with large amount of information and low correlation should be selected. On this basis, according to the needs of target detection applications, the spectral characteristics of the objects of interest are taken into consideration in this paper, and a new method based on spectrum difference is proposed. Firstly, according to the spectrum differences of targets of interest, a difference matrix which represents the different spectral reflectance of different targets in different bands is structured. By setting a threshold, the bands satisfying the conditions would be left, constituting a subset of bands. Then, the correlation coefficients between bands are calculated and correlation matrix is given. According to the size of the correlation coefficient, the bands can be set into several groups. At last, the conception of normalized variance is used on behalf of the information content of each band. The bands are sorted by the value of its normalized variance. Set needing number of bands, and the optimum band combination solution can be get by these three steps. This method retains the greatest degree of difference between the target of interest and is easy to achieve by computer automatically. Besides, false color image synthesis experiment is carried out using the bands selected by this method as well as other 3 methods to show the performance of method in this paper.

A study on the spectrum analyzing of internal leak in valve for power plant using acoustic emission method

International Nuclear Information System (INIS)

Lee, Sang Guk; Lee, Sun Ki; Lee, Jun Shin; Sohn, Seok Man

2004-01-01

The purpose of this study is to estimate the availability of acoustic emission method to the internal leak of the valves at nuclear power plants. The acoustic emission method was applied to the valves at the site, and the background noise was measured for the abnormal plant condition. From the comparison of the background noise data with the experimental results as to relation between leak flow and acoustic signal, the minimum leak flow rates that can be detected by acoustic signal was suggested. When the background levels are higher than the acoustic signal, the method described below was considered that the analysis the remainder among the background noise frequency spectrum and the acoustic signal spectrum become a very useful leak detection method. A few experimental examples of the spectrum analysis that varied the background noise characteristic were given

Microstrip natural wave spectrum mathematical model using partial inversion method

International Nuclear Information System (INIS)

Pogarsky, S.A.; Litvinenko, L.N.; Prosvirnin, S.L.

1995-01-01

It is generally agreed that both microstrip lines itself and different discontinuities based on microstrips are the most difficult problem for accurate electrodynamic analysis. Over the last years much has been published about principles and accurate (or full wave) methods of microstrip lines investigations. The growing interest for this problem may be explained by the microstrip application in the millimeter-wave range for purpose of realizing interconnects and a variety of passive components. At these higher operating rating frequencies accurate component modeling becomes more critical. A creation, examination and experimental verification of the accurate method for planar electrodynamical structures natural wave spectrum investigations are the objects of this manuscript. The moment method with partial inversion operator method using may be considered as a basical way for solving this problem. This method is outlook for accurate analysis of different planar discontinuities in microstrip: such as step discontinuities, microstrip turns, Y- and X-junctions and etc., substrate space steps dielectric constants and other anisotropy types

Error evaluation of inelastic response spectrum method for earthquake design

International Nuclear Information System (INIS)

Paz, M.; Wong, J.

1981-01-01

Two-story, four-story and ten-story shear building-type frames subjected to earthquake excitaion, were analyzed at several levels of their yield resistance. These frames were subjected at their base to the motion recorded for north-south component of the 1940 El Centro earthquake, and to an artificial earthquake which would produce the response spectral charts recommended for design. The frames were first subjected to 25% or 50% of the intensity level of these earthquakes. The resulting maximum relative displacement for each story of the frames was assumed to be yield resistance for the subsequent analyses at 100% of intensity for the excitation. The frames analyzed were uniform along their height with the stiffness adjusted as to result in 0.20 seconds of the fundamental period for the two-story frame, 0.40 seconds for the four-story frame and 1.0 seconds for the ten-story frame. Results of the study provided the following conclusions: (1) The percentage error in floor displacement for linear behavior was less than 10%; (2) The percentage error in floor displacement for inelastic behavior (elastoplastic) could be as high as 100%; (3) In most of the cases analyzed, the error increased with damping in the system; (4) As a general rule, the error increased as the modal yield resistance decreased; (5) The error was lower for the structures subjected to the 1940 E1 Centro earthquake than for the same structures subjected to an artificial earthquake which was generated from the response spectra for design. (orig./HP)

Altered responses to social chemosignals in autism spectrum disorder.

Science.gov (United States)

Endevelt-Shapira, Yaara; Perl, Ofer; Ravia, Aharon; Amir, Daniel; Eisen, Ami; Bezalel, Vered; Rozenkrantz, Liron; Mishor, Eva; Pinchover, Liron; Soroka, Timna; Honigstein, Danielle; Sobel, Noam

2018-01-01

Autism spectrum disorder (ASD) is characterized by impaired social communication, often attributed to misreading of emotional cues. Why individuals with ASD misread emotions remains unclear. Given that terrestrial mammals rely on their sense of smell to read conspecific emotions, we hypothesized that misreading of emotional cues in ASD partially reflects altered social chemosignaling. We found no difference between typically developed (TD) and cognitively able adults with ASD at explicit detection and perception of social chemosignals. Nevertheless, TD and ASD participants dissociated in their responses to subliminal presentation of these same compounds: the undetected 'smell of fear' (skydiver sweat) increased physiological arousal and reduced explicit and implicit measures of trust in TD but acted opposite in ASD participants. Moreover, two different undetected synthetic putative social chemosignals increased or decreased arousal in TD but acted opposite in ASD participants. These results implicate social chemosignaling as a sensory substrate of social impairment in ASD.

Affective neural response to restricted interests in autism spectrum disorders.

Science.gov (United States)

Cascio, Carissa J; Foss-Feig, Jennifer H; Heacock, Jessica; Schauder, Kimberly B; Loring, Whitney A; Rogers, Baxter P; Pryweller, Jennifer R; Newsom, Cassandra R; Cockhren, Jurnell; Cao, Aize; Bolton, Scott

2014-01-01

Restricted interests are a class of repetitive behavior in autism spectrum disorders (ASD) whose intensity and narrow focus often contribute to significant interference with daily functioning. While numerous neuroimaging studies have investigated executive circuits as putative neural substrates of repetitive behavior, recent work implicates affective neural circuits in restricted interests. We sought to explore the role of affective neural circuits and determine how restricted interests are distinguished from hobbies or interests in typical development. We compared a group of children with ASD to a typically developing (TD) group of children with strong interests or hobbies, employing parent report, an operant behavioral task, and functional imaging with personalized stimuli based on individual interests. While performance on the operant task was similar between the two groups, parent report of intensity and interference of interests was significantly higher in the ASD group. Both the ASD and TD groups showed increased BOLD response in widespread affective neural regions to the pictures of their own interest. When viewing pictures of other children's interests, the TD group showed a similar pattern, whereas BOLD response in the ASD group was much more limited. Increased BOLD response in the insula and anterior cingulate cortex distinguished the ASD from the TD group, and parent report of the intensity and interference with daily life of the child's restricted interest predicted insula response. While affective neural network response and operant behavior are comparable in typical and restricted interests, the narrowness of focus that clinically distinguishes restricted interests in ASD is reflected in more interference in daily life and aberrantly enhanced insula and anterior cingulate response to individuals' own interests in the ASD group. These results further support the involvement of affective neural networks in repetitive behaviors in ASD. © 2013 The

Method to deduce the energy spectrum by the Pierre Auger Observatory

Energy Technology Data Exchange (ETDEWEB)

Maris, I.; Roth, M.; Schmidt, T.; Schuessler, F.; Unger, M. [Univ. Karlsruhe (Germany); Bluemer, J. [Univ. Karlsruhe (Germany); Forschungszentrum Karlsruhe (Germany)

2007-07-01

Taken into account the great advantage of having a hybrid detector it has been developed a method, simulation independent, to determine the energy of the comic rays recorded by the surface detector of the Pierre Auger Observatory. The method assumes that the cosmic ray flux has the same distribution in zenith angle for all energy ranges. Therefore one can relate the calorimetric measurement of the fluorescence detector of the CR energy with a SD quantity, e.g. shower size at 1000m distance from the core, corrected for the different attenuations in the atmosphere. The method of measuring and calibrating the primary energy and the influence of reconstruction uncertainties on the energy spectrum are presented. (orig.)

Speech spectrum's correlation with speakers' Eysenck personality traits.

Directory of Open Access Journals (Sweden)

Chao Hu

Full Text Available The current study explored the correlation between speakers' Eysenck personality traits and speech spectrum parameters. Forty-six subjects completed the Eysenck Personality Questionnaire. They were instructed to verbally answer the questions shown on a computer screen and their responses were recorded by the computer. Spectrum parameters of /sh/ and /i/ were analyzed by Praat voice software. Formant frequencies of the consonant /sh/ in lying responses were significantly lower than that in truthful responses, whereas no difference existed on the vowel /i/ speech spectrum. The second formant bandwidth of the consonant /sh/ speech spectrum was significantly correlated with the personality traits of Psychoticism, Extraversion, and Neuroticism, and the correlation differed between truthful and lying responses, whereas the first formant frequency of the vowel /i/ speech spectrum was negatively correlated with Neuroticism in both response types. The results suggest that personality characteristics may be conveyed through the human voice, although the extent to which these effects are due to physiological differences in the organs associated with speech or to a general Pygmalion effect is yet unknown.

Hybrid spread spectrum radio system

Science.gov (United States)

Smith, Stephen F [London, TN; Dress, William B [Camas, WA

2010-02-09

Systems and methods are described for hybrid spread spectrum radio systems. A method, includes receiving a hybrid spread spectrum signal including: fast frequency hopping demodulating and direct sequence demodulating a direct sequence spread spectrum signal, wherein multiple frequency hops occur within a single data-bit time and each bit is represented by chip transmissions at multiple frequencies.

Photoneutron spectrum measured with Bonner Spheres in Planetary method mode

Energy Technology Data Exchange (ETDEWEB)

Benites R, J. [Centro Estatal de Cancerologia de Nayarit, Servicio de Seguridad Radiologica, Calz. de la Cruz 118 Sur, 63000 Tepic, Nayarit (Mexico); Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Apdo. Postal 336, 98000 Zacatecas (Mexico); Velazquez F, J., E-mail: jlbenitesr@prodigy.net.mx [Universidad Autonoma de Nayarit, Posgrado en Ciencias Biologico Agropecuarias, Carretera Tepic-Compostela Km 9, 63780 Jalisco-Nayarit (Mexico)

2012-10-15

We measured the spectrum of photoneutrons at 100 cm isocenter linear accelerator (Linac) Varian ix operating at 15 MV Bremsstrahlung mode. In this process was used a radiation field of 20 x 20 cm{sup 2} at a depth of 5 cm in a solid water phantom with dimensions of 30 x 30 x 15 cm{sup 3}. The measurement was performed with a system using it Bonner Spheres spectrometric method Planetary mode. As neutron detector of the spectrometer is used thermoluminescent dosimeters pairs of type 600 and 700. (Author)

Photoneutron spectrum measured with Bonner Spheres in Planetary method mode

International Nuclear Information System (INIS)

Benites R, J.; Vega C, H. R.; Velazquez F, J.

2012-10-01

We measured the spectrum of photoneutrons at 100 cm isocenter linear accelerator (Linac) Varian ix operating at 15 MV Bremsstrahlung mode. In this process was used a radiation field of 20 x 20 cm 2 at a depth of 5 cm in a solid water phantom with dimensions of 30 x 30 x 15 cm 3 . The measurement was performed with a system using it Bonner Spheres spectrometric method Planetary mode. As neutron detector of the spectrometer is used thermoluminescent dosimeters pairs of type 600 and 700. (Author)

Development of methods to predict both the dynamic and the pseudo-static response of secondary structures subjected to seismic excitations

International Nuclear Information System (INIS)

Subudhi, M.; Bezler, P.

1984-01-01

Multiple independent support excitation time history formulations have been used to investigate simplified methods to predict the inertial (or dynamic) component of response as well as the pseudo-static (or static) component of response of secondary structures subjected to seismic excitations. For the dynamic component the independent response spectrum method is used with current industry practice for the modal and direction of excitation combinations being adopted and various procedures for the group combination and sequence being investigated. SRSS combination between support groups is found to yield satisfactory results. For the static component, support grouping by elevation for preliminary design followed by support grouping by attachment point for final design assure overall safety in the design

Equivalent non-Gaussian excitation method for response moment calculation of systems under non-Gaussian random excitation

International Nuclear Information System (INIS)

Tsuchida, Takahiro; Kimura, Koji

2015-01-01

Equivalent non-Gaussian excitation method is proposed to obtain the moments up to the fourth order of the response of systems under non-Gaussian random excitation. The excitation is prescribed by the probability density and power spectrum. Moment equations for the response can be derived from the stochastic differential equations for the excitation and the system. However, the moment equations are not closed due to the nonlinearity of the diffusion coefficient in the equation for the excitation. In the proposed method, the diffusion coefficient is replaced with the equivalent diffusion coefficient approximately to obtain a closed set of the moment equations. The square of the equivalent diffusion coefficient is expressed by the second-order polynomial. In order to demonstrate the validity of the method, a linear system to non-Gaussian excitation with generalized Gaussian distribution is analyzed. The results show the method is applicable to non-Gaussian excitation with the widely different kurtosis and bandwidth. (author)

Probabilistic Seismic Hazard Assessment Method for Nonlinear Soil Sites based on the Hazard Spectrum of Bedrock Sites

International Nuclear Information System (INIS)

Hahm, Dae Gi; Seo, Jeong Moon; Choi, In Kil

2011-01-01

For the probabilistic safety assessment of the nuclear power plants (NPP) under seismic events, the rational probabilistic seismic hazard estimation should be performed. Generally, the probabilistic seismic hazard of NPP site is represented by the uniform hazard spectrum (UHS) for the specific annual frequency. In most case, since that the attenuation equations were defined for the bedrock sites, the standard attenuation laws cannot be applied to the general soft soil sites. Hence, for the probabilistic estimation of the seismic hazard of soft soil sites, a methodology of probabilistic seismic hazard analysis (PSHA) coupled with nonlinear dynamic analyses of the soil column are required. Two methods are commonly used for the site response analysis considering the nonlinearity of sites. The one is the deterministic method and another is the probabilistic method. In the analysis of site response, there exist many uncertainty factors such as the variation of the magnitude and frequency contents of input ground motion, and material properties of soil deposits. Hence, nowadays, it is recommended that the adoption of the probabilistic method for the PSHA of soft soil deposits considering such uncertainty factors. In this study, we estimated the amplification factor of the surface of the soft soil deposits with considering the uncertainties of the input ground motions and the soil material properties. Then, we proposed the probabilistic methodology to evaluate the UHS of the soft soil site by multiplying the amplification factor to that of the bedrock site. The proposed method was applied to four typical target sites of KNGR and APR1400 NPP site categories

Response approach to the squeezed-limit bispectrum: application to the correlation of quasar and Lyman-α forest power spectrum

Energy Technology Data Exchange (ETDEWEB)

Chiang, Chi-Ting [C.N. Yang Institute for Theoretical Physics, Stony Brook University, Stony Brook, NY 11794 (United States); Cieplak, Agnieszka M.; Slosar, Anže [Brookhaven National Laboratory, Blgd 510, Upton, NY 11375 (United States); Schmidt, Fabian, E-mail: chi-ting.chiang@stonybrook.edu, E-mail: acieplak@bnl.gov, E-mail: fabians@mpa-garching.mpg.de, E-mail: anze@bnl.gov [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85741 Garching (Germany)

2017-06-01

The squeezed-limit bispectrum, which is generated by nonlinear gravitational evolution as well as inflationary physics, measures the correlation of three wavenumbers, in the configuration where one wavenumber is much smaller than the other two. Since the squeezed-limit bispectrum encodes the impact of a large-scale fluctuation on the small-scale power spectrum, it can be understood as how the small-scale power spectrum ''responds'' to the large-scale fluctuation. Viewed in this way, the squeezed-limit bispectrum can be calculated using the response approach even in the cases which do not submit to perturbative treatment. To illustrate this point, we apply this approach to the cross-correlation between the large-scale quasar density field and small-scale Lyman-α forest flux power spectrum. In particular, using separate universe simulations which implement changes in the large-scale density, velocity gradient, and primordial power spectrum amplitude, we measure how the Lyman-α forest flux power spectrum responds to the local, long-wavelength quasar overdensity, and equivalently their squeezed-limit bispectrum. We perform a Fisher forecast for the ability of future experiments to constrain local non-Gaussianity using the bispectrum of quasars and the Lyman-α forest. Combining with quasar and Lyman-α forest power spectra to constrain the biases, we find that for DESI the expected 1−σ constraint is err[ f {sub NL}]∼60. Ability for DESI to measure f {sub NL} through this channel is limited primarily by the aliasing and instrumental noise of the Lyman-α forest flux power spectrum. The combination of response approach and separate universe simulations provides a novel technique to explore the constraints from the squeezed-limit bispectrum between different observables.

Generation of artificial time-histories, rich in all frequencies, from given response spectra

International Nuclear Information System (INIS)

Levy, S.; Wilkinson, J.P.D.

1976-01-01

In the design of nuclear power plants, it has been found desirable in certain instances to use the time-history method of dynamic analysis to determine the plant response to seismic input. In the implementation of this method, it is necessary to determine an adequate representation of the excitation as a function of time. Because many design criteria are specified in terms of design response spectra one is faced with the problem of generating a time-history whose own response spectrum approximates as far as possible to the originally specified design response spectrum. One objective of this paper is to present a method of synthesizing such time-histories from a given design response spectrum. The design response spectra may be descriptive of floor responses at a particular location in a plant, or they may be descriptive of seismic ground motions at a plant site. The method described in this paper allows the generation of time histories that are rich in all frequencies in the spectrum. This richness is achieved by choosing a large number of closely-spaced frequency points such that the half-power points of adjacent frequencies overlap. Examples are given concerning seismic design response spectra, and a number of points are discussed concerning the effect of frequency spacing on convergence. (Auth.)

Development of an evaluation method for seismic isolation systems of nuclear power facilities. Seismic design analysis methods for crossover piping system

International Nuclear Information System (INIS)

Tai, Koichi; Sasajima, Keisuke; Fukushima, Shunsuke; Takamura, Noriyuki; Onishi, Shigenobu

2014-01-01

This paper provides seismic design analysis methods suitable for crossover piping system, which connects between seismic isolated building and non-isolated building in the seismic isolated nuclear power plant. Through the numerical study focused on the main steam crossover piping system, seismic response spectrum analysis applying ISM (Independent Support Motion) method with SRSS combination or CCFS (Cross-oscillator, Cross-Floor response Spectrum) method has found to be quite effective for the seismic design of multiply supported crossover piping system. (author)

Spectrum Trading in India and 5G

DEFF Research Database (Denmark)

Tripathi, Purnendu; Prasad, Ramjee

2013-01-01

Currently radio spectrum is largely managed through Command and Control method. Public mobile services require spectrum below 3 GHz for providing cost effective services. The existing method has created artificial shortage of spectrum especially below 3 GHz. Spectrum trading is a new concept...

A Spectrum Sensing Method Based on Signal Feature and Clustering Algorithm in Cognitive Wireless Multimedia Sensor Networks

Directory of Open Access Journals (Sweden)

Yongwei Zhang

2017-01-01

Full Text Available In order to solve the problem of difficulty in determining the threshold in spectrum sensing technologies based on the random matrix theory, a spectrum sensing method based on clustering algorithm and signal feature is proposed for Cognitive Wireless Multimedia Sensor Networks. Firstly, the wireless communication signal features are obtained according to the sampling signal covariance matrix. Then, the clustering algorithm is used to classify and test the signal features. Different signal features and clustering algorithms are compared in this paper. The experimental results show that the proposed method has better sensing performance.

A time-frequency analysis method to obtain stable estimates of magnetotelluric response function based on Hilbert-Huang transform

Science.gov (United States)

Cai, Jianhua

2017-05-01

The time-frequency analysis method represents signal as a function of time and frequency, and it is considered a powerful tool for handling arbitrary non-stationary time series by using instantaneous frequency and instantaneous amplitude. It also provides a possible alternative to the analysis of the non-stationary magnetotelluric (MT) signal. Based on the Hilbert-Huang transform (HHT), a time-frequency analysis method is proposed to obtain stable estimates of the magnetotelluric response function. In contrast to conventional methods, the response function estimation is performed in the time-frequency domain using instantaneous spectra rather than in the frequency domain, which allows for imaging the response parameter content as a function of time and frequency. The theory of the method is presented and the mathematical model and calculation procedure, which are used to estimate response function based on HHT time-frequency spectrum, are discussed. To evaluate the results, response function estimates are compared with estimates from a standard MT data processing method based on the Fourier transform. All results show that apparent resistivities and phases, which are calculated from the HHT time-frequency method, are generally more stable and reliable than those determined from the simple Fourier analysis. The proposed method overcomes the drawbacks of the traditional Fourier methods, and the resulting parameter minimises the estimation bias caused by the non-stationary characteristics of the MT data.

Integration of auto analysis program of gamma spectrum and software and determination of element content in sample by k-zero method

International Nuclear Information System (INIS)

Trinh Quang Vinh; Truong Thi Hong Loan; Mai Van Nhon; Huynh Truc Phuong

2014-01-01

Integrating the gamma spectrum auto-analysis program with elemental analysis software by k-zero method is the objective for many researchers. This work is the first stepin building an auto analysis program of gamma spectrum, which includes modules of reading spectrum, displaying spectrum, calibrating energy of peak, smoothing spectrum, calculating peak area and determining content of elements in sample. Then, the results from the measurements of standard samples by a low level spectrometer using HPGe detector are compared to those of other gamma spectrum auto-analysis programs. (author)

A survey of genomic studies supports association of circadian clock genes with bipolar disorder spectrum illnesses and lithium response.

Directory of Open Access Journals (Sweden)

Michael J McCarthy

Full Text Available Circadian rhythm abnormalities in bipolar disorder (BD have led to a search for genetic abnormalities in circadian "clock genes" associated with BD. However, no significant clock gene findings have emerged from genome-wide association studies (GWAS. At least three factors could account for this discrepancy: complex traits are polygenic, the organization of the clock is more complex than previously recognized, and/or genetic risk for BD may be shared across multiple illnesses. To investigate these issues, we considered the clock gene network at three levels: essential "core" clock genes, upstream circadian clock modulators, and downstream clock controlled genes. Using relaxed thresholds for GWAS statistical significance, we determined the rates of clock vs. control genetic associations with BD, and four additional illnesses that share clinical features and/or genetic risk with BD (major depression, schizophrenia, attention deficit/hyperactivity. Then we compared the results to a set of lithium-responsive genes. Associations with BD-spectrum illnesses and lithium-responsiveness were both enriched among core clock genes but not among upstream clock modulators. Associations with BD-spectrum illnesses and lithium-responsiveness were also enriched among pervasively rhythmic clock-controlled genes but not among genes that were less pervasively rhythmic or non-rhythmic. Our analysis reveals previously unrecognized associations between clock genes and BD-spectrum illnesses, partly reconciling previously discordant results from past GWAS and candidate gene studies.

A method of loss free compression for the data of nuclear spectrum

International Nuclear Information System (INIS)

Sun Mingshan; Wu Shiying; Chen Yantao; Xu Zurun

2000-01-01

A new method of loss free compression based on the feature of the data of nuclear spectrum is provided, from which a practicable algorithm is successfully derived. A compression rate varying from 0.50 to 0.25 is obtained and the distribution of the processed data becomes even more suitable to be reprocessed by another compression such as Huffman Code to improve the compression rate

Missing and delayed auditory responses in young and older children with autism spectrum disorders

Directory of Open Access Journals (Sweden)

J. Christopher eEdgar

2014-06-01

Full Text Available Background: The development of left and right superior temporal gyrus (STG 50ms (M50 and 100ms (M100 auditory responses in typically developing children (TD and in children with autism spectrum disorder (ASD was examined. It was hypothesized that (1 M50 responses would be observed equally often in younger and older children, (2 M100 responses would be observed more often in older than younger children indicating later development of secondary auditory areas, and (3 M100 but not M50 would be observed less often in ASD than TD in both age groups, reflecting slower maturation of later developing auditory areas in ASD. Methods: 35 typically developing controls, 63 ASD without language impairment (ASD-LI, and 38 ASD with language impairment (ASD+LI were recruited.The presence or absence of a STG M50 and M100 was scored. Subjects were grouped into younger (6 to 10-years-old and older groups (11 to 15-years-old. Results: Although M50 responses were observed equally often in older and younger subjects and equally often in TD and ASD, left and right M50 responses were delayed in ASD-LI and ASD+LI. Group comparisons showed that in younger subjects M100 responses were observed more often in TD than ASD+LI (90% vs 66%, p=0.04, with no differences between TD and ASD-LI (90% vs 76% p=0.14 or between ASD-LI and ASD+LI (76% vs 66%, p=0.53. In older subjects, whereas no differences were observed between TD and ASD+LI, responses were observed more often in ASD-LI than ASD+LI. Conclusions: Although present in all groups, M50 responses were delayed in ASD, suggesting delayed development of earlier developing auditory areas. Examining the TD data, findings indicated that by 11 years a right M100 should be observed in 100% of subjects and a left M100 in 80% of subjects. Thus, by 11years, lack of a left and especially right M100 offers neurobiological insight into sensory processing that may underlie language or cognitive impairment.

Non-perturbative methodologies for low-dimensional strongly-correlated systems: From non-Abelian bosonization to truncated spectrum methods.

Science.gov (United States)

James, Andrew J A; Konik, Robert M; Lecheminant, Philippe; Robinson, Neil J; Tsvelik, Alexei M

2018-02-26

We review two important non-perturbative approaches for extracting the physics of low-dimensional strongly correlated quantum systems. Firstly, we start by providing a comprehensive review of non-Abelian bosonization. This includes an introduction to the basic elements of conformal field theory as applied to systems with a current algebra, and we orient the reader by presenting a number of applications of non-Abelian bosonization to models with large symmetries. We then tie this technique into recent advances in the ability of cold atomic systems to realize complex symmetries. Secondly, we discuss truncated spectrum methods for the numerical study of systems in one and two dimensions. For one-dimensional systems we provide the reader with considerable insight into the methodology by reviewing canonical applications of the technique to the Ising model (and its variants) and the sine-Gordon model. Following this we review recent work on the development of renormalization groups, both numerical and analytical, that alleviate the effects of truncating the spectrum. Using these technologies, we consider a number of applications to one-dimensional systems: properties of carbon nanotubes, quenches in the Lieb-Liniger model, 1  +  1D quantum chromodynamics, as well as Landau-Ginzburg theories. In the final part we move our attention to consider truncated spectrum methods applied to two-dimensional systems. This involves combining truncated spectrum methods with matrix product state algorithms. We describe applications of this method to two-dimensional systems of free fermions and the quantum Ising model, including their non-equilibrium dynamics.

Non-perturbative methodologies for low-dimensional strongly-correlated systems: From non-Abelian bosonization to truncated spectrum methods

Science.gov (United States)

James, Andrew J. A.; Konik, Robert M.; Lecheminant, Philippe; Robinson, Neil J.; Tsvelik, Alexei M.

2018-04-01

We review two important non-perturbative approaches for extracting the physics of low-dimensional strongly correlated quantum systems. Firstly, we start by providing a comprehensive review of non-Abelian bosonization. This includes an introduction to the basic elements of conformal field theory as applied to systems with a current algebra, and we orient the reader by presenting a number of applications of non-Abelian bosonization to models with large symmetries. We then tie this technique into recent advances in the ability of cold atomic systems to realize complex symmetries. Secondly, we discuss truncated spectrum methods for the numerical study of systems in one and two dimensions. For one-dimensional systems we provide the reader with considerable insight into the methodology by reviewing canonical applications of the technique to the Ising model (and its variants) and the sine-Gordon model. Following this we review recent work on the development of renormalization groups, both numerical and analytical, that alleviate the effects of truncating the spectrum. Using these technologies, we consider a number of applications to one-dimensional systems: properties of carbon nanotubes, quenches in the Lieb–Liniger model, 1  +  1D quantum chromodynamics, as well as Landau–Ginzburg theories. In the final part we move our attention to consider truncated spectrum methods applied to two-dimensional systems. This involves combining truncated spectrum methods with matrix product state algorithms. We describe applications of this method to two-dimensional systems of free fermions and the quantum Ising model, including their non-equilibrium dynamics.

Application of a spectrum standardization method for carbon analysis in coal using laser-induced breakdown spectroscopy (LIBS).

Science.gov (United States)

Li, Xiongwei; Wang, Zhe; Fu, Yangting; Li, Zheng; Liu, Jianmin; Ni, Weidou

2014-01-01

Measurement of coal carbon content using laser-induced breakdown spectroscopy (LIBS) is limited by its low precision and accuracy. A modified spectrum standardization method was proposed to achieve both reproducible and accurate results for the quantitative analysis of carbon content in coal using LIBS. The proposed method used the molecular emissions of diatomic carbon (C2) and cyanide (CN) to compensate for the diminution of atomic carbon emissions in high volatile content coal samples caused by matrix effect. The compensated carbon line intensities were further converted into an assumed standard state with standard plasma temperature, electron number density, and total number density of carbon, under which the carbon line intensity is proportional to its concentration in the coal samples. To obtain better compensation for fluctuations of total carbon number density, the segmental spectral area was used and an iterative algorithm was applied that is different from our previous spectrum standardization calculations. The modified spectrum standardization model was applied to the measurement of carbon content in 24 bituminous coal samples. The results demonstrate that the proposed method has superior performance over the generally applied normalization methods. The average relative standard deviation was 3.21%, the coefficient of determination was 0.90, the root mean square error of prediction was 2.24%, and the average maximum relative error for the modified model was 12.18%, showing an overall improvement over the corresponding values for the normalization with segmental spectrum area, 6.00%, 0.75, 3.77%, and 15.40%, respectively.

Application of Monte Carlo method in determination of air absorbed rate from a full γ-ray spectrum

International Nuclear Information System (INIS)

Zhang Jiangyun; Huang Ning; Tang Lili; Liu Yanfang; Zhang Guanghua

2011-01-01

The dosimetric properties of a gamma-radiation field can be measured by a dose-rate meter or by a gamma-spectrometer with spectrum-dose conversion. One of the spectrum dose conversion methods is to evaluate the radiation dose directly from integrating the observed pulse height spectrum weighted by a G(E) function, instead of making spectrum analysis.In this paper,energy spectra of 11 single energy point sources in 0.1-2.5 MeV are simulated by using Monte Carlo software MCNP5 for NaI(Tl) detectors of Φ 75 mm x 75 mm, Φ 50 mm x 50 mm and Φ 25 mm x 25 mm. The energy spectra are used as standard spectrum to calculate the G(E) value, so as to calculate corresponding doses. Comparing the results with theoretical value,the error is less than 1.5%. Finally, the G(E)-based γ dose rate of radiation field agreed well (within 5%) with the dose rate measured by a dosimeter. (authors)

Real time spectrum analysis

International Nuclear Information System (INIS)

Blunden, A.; O'Prey, D.G.; Tait, W.H.

1983-01-01

A method is described for the separation of a composite pulse-height spectrum into its unresolved component parts, which belong to a set of measured library spectra. The method allows real-time estimation giving running estimates during acquisition of the spectrum, minimises computation space, especially for a number of parallel calculations, estimates in advance the rms errors, and produces a significance measure for the hypothesis that the composite contains only the library spectra. Least squares curve-fitting, and other methods, can be compared, with the formalism developed, allowing analytical comparison of the effect of detector energy resolution and detection efficiency. A rational basis for the choice between the various methods of spectrum analysis follows from the theory, minimising rms estimation errors. The method described is applicable for very low numbers of counts and poor resolution. (orig.)

Galaxy power-spectrum responses and redshift-space super-sample effect

Science.gov (United States)

Li, Yin; Schmittfull, Marcel; Seljak, Uroš

2018-02-01

As a major source of cosmological information, galaxy clustering is susceptible to long-wavelength density and tidal fluctuations. These long modes modulate the growth and expansion rate of local structures, shifting them in both amplitude and scale. These effects are often named the growth and dilation effects, respectively. In particular the dilation shifts the baryon acoustic oscillation (BAO) peak and breaks the assumption of the Alcock-Paczynski (AP) test. This cannot be removed with reconstruction techniques because the effect originates from long modes outside the survey. In redshift space, the long modes generate a large-scale radial peculiar velocity that affects the redshift-space distortion (RSD) signal. We compute the redshift-space response functions of the galaxy power spectrum to long density and tidal modes at leading order in perturbation theory, including both the growth and dilation terms. We validate these response functions against measurements from simulated galaxy mock catalogs. As one application, long density and tidal modes beyond the scale of a survey correlate various observables leading to an excess error known as the super-sample covariance, and thus weaken their constraining power. We quantify the super-sample effect on BAO, AP, and RSD measurements, and study its impact on current and future surveys.

Entropy Spectrum of Black Holes of Heterotic String Theory via Adiabatic Invariance

Institute of Scientific and Technical Information of China (English)

Alexis Larra？ aga; Luis Cabarique; Manuel Londo？ o

2012-01-01

Using adiabatic invariance and the Bohr-Sommerfeld quantization rule we investigate the entropy spectroscopy of two black holes of heterotic string theory,the charged GMGHS and the rotating Sen solutions.It is shown that the entropy spectrum is equally spaced in both cases,identically to the spectrum obtained before for Schwarzschild,Reissner-Nordstr?m and Kerr black holes.Since the adiabatic invariance method does not use quasinormal mode analysis,there is no need to impose the small charge or small angular momentum limits and there is no confusion on whether the real part or the imaginary part of the modes is responsible for the entropy spectrum.

Linear response to long wavelength fluctuations using curvature simulations

Energy Technology Data Exchange (ETDEWEB)

Baldauf, Tobias; Zaldarriaga, Matias [School of Natural Sciences, Institute for Advanced Study, Princeton, NJ (United States); Seljak, Uroš [Physics Department, Astronomy Department and Lawrence Berkeley National Laboratory, University of California, Berkeley, CA (United States); Senatore, Leonardo, E-mail: baldauf@ias.edu, E-mail: useljak@berkeley.edu, E-mail: senatore@stanford.edu, E-mail: matiasz@ias.edu [Stanford Institute for Theoretical Physics, Stanford University, Stanford, CA (United States)

2016-09-01

We study the local response to long wavelength fluctuations in cosmological N -body simulations, focusing on the matter and halo power spectra, halo abundance and non-linear transformations of the density field. The long wavelength mode is implemented using an effective curved cosmology and a mapping of time and distances. The method provides an alternative, more direct, way to measure the isotropic halo biases. Limiting ourselves to the linear case, we find generally good agreement between the biases obtained from the curvature method and the traditional power spectrum method at the level of a few percent. We also study the response of halo counts to changes in the variance of the field and find that the slope of the relation between the responses to density and variance differs from the naïve derivation assuming a universal mass function by approximately 8–20%. This has implications for measurements of the amplitude of local non-Gaussianity using scale dependent bias. We also analyze the halo power spectrum and halo-dark matter cross-spectrum response to long wavelength fluctuations and derive second order halo bias from it, as well as the super-sample variance contribution to the galaxy power spectrum covariance matrix.

A fast quadrature-based numerical method for the continuous spectrum biphasic poroviscoelastic model of articular cartilage.

Science.gov (United States)

Stuebner, Michael; Haider, Mansoor A

2010-06-18

A new and efficient method for numerical solution of the continuous spectrum biphasic poroviscoelastic (BPVE) model of articular cartilage is presented. Development of the method is based on a composite Gauss-Legendre quadrature approximation of the continuous spectrum relaxation function that leads to an exponential series representation. The separability property of the exponential terms in the series is exploited to develop a numerical scheme that can be reduced to an update rule requiring retention of the strain history at only the previous time step. The cost of the resulting temporal discretization scheme is O(N) for N time steps. Application and calibration of the method is illustrated in the context of a finite difference solution of the one-dimensional confined compression BPVE stress-relaxation problem. Accuracy of the numerical method is demonstrated by comparison to a theoretical Laplace transform solution for a range of viscoelastic relaxation times that are representative of articular cartilage. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Application of thermoluminescence dosimeter on the measurement of hard X-ray pulse energy spectrum

International Nuclear Information System (INIS)

Song Zhaohui; Wang Baohui; Wang Kuilu; Hei Dongwei; Sun Fengrong; Li Gang

2003-01-01

This paper introduces the application of thermoluminescence dosimeter (TLD) which composed by TLD-3500 reader and GR-100 M chips on the measurement of hard X-ray pulse energy spectrum. The idea using Filter Fluorescence Method (FFM) and TLD to measure hard X-ray pulse energy spectrum (from 10 keV to 100 keV) is discussed in details. Considering all the factors of the measuring surrounding, the measurement system of hard X-ray pulse has been devised. The calibration technique of absolute energy response of TLD is established. This method has been applied successfully on the radiation parameters measurement of the huge pulse radiation device-high-power pulser I. Hard X-ray pulse energy spectrum data of the pulser are acquired

Assessing the Accuracy of the Modified Chinese Autism Spectrum Rating Scale and Social Responsiveness Scale for Screening Autism Spectrum Disorder in Chinese Children

Institute of Scientific and Technical Information of China (English)

Bingrui Zhou; Hao Zhou; Lijie Wu; Xiaobing Zou; Xuerong Luo; Eric Fombonne; Yi Wang; Weili Yan; Xiu Xu

2017-01-01

The reported prevalence of autism spectrum disorder (ASD) has been increasing rapidly in many parts of the world.However,data on its prevalence in China are largely missing.Here,we assessed the suitability of the modified Chinese version of a newly-developed ASD screening tool,the Modified Chinese Autism Spectrum Rating Scales (MC-ASRS) in screening for ASD in Chinese children aged 6-12 years,through comparison with the Social Responsiveness Scale (SRS) that has been widely used for ASD screening.We recruited the parents/caregivers of 1588 typically-developing children and 190 children with ASD aged 6-12 years to complete the MC-ASRS and SRS,and evaluated the validity of both scales in discriminating children with ASD from those developing typically.The results showed that MC-ASRS performed as well as SRS in sensitivity,specificity,and area-under-the-curve (both ＞0.95) in receiver operating characteristic analysis,with a fair false-negative rate.These results suggest that MC-ASRS is a promising tool for screening for children with ASD in the general Chinese population.

Some lemma on spectrum of eigen value regarding power method

Science.gov (United States)

Jamali, A. R. M. Jalal Uddin; Alam, Md. Sah

2017-04-01

Eigen value problems arise in almost all science and engineering fields. There exist some smart methods in literature in which most of them are able to find only Eigen values but could not find corresponding Eigen vectors. There exist many engineering as well as scientific fields in which both largest as well as smallest Eigen pairs are required. Power method is very simple but a powerful tool for finding largest Eigen value and corresponding Eigen vector (Eigen-pair). Again Inverse Power method is applied to find out smallest Eigen-pair and/or desire Eigen-pairs. But it is known that Inverse Power method is computationally very costly. On the other hand by using shifting property, Power method can find further Eigen-pairs. But the position of this Eigen value in the set of spectrum of the Eigen values is not identified. In this regard we proposed four lemma associate with Modified Power method. Each Lemma is proved ornately. The Modified Power method is implemented and illustrates an example for the verification of the Lemma. By using lemma the modified power algorithm is able to find out both largest and smallest Eigen-pairs successfully and efficiently in some cases. Moreover by the help of the Lemma, algorithm is able to detect the nature (positive and negative) of the Eigen values.

Experimental and mathematical simulation techniques for determining an in-situ response testing method for neutron sensors used in reactor power plant protection systems

International Nuclear Information System (INIS)

Behbahani, A.

1983-01-01

An analytical neutron sensor response model and methods for transient response measurements of neutron sensors (compensated ionization chamber), including possible in-situ techniques have been developed and evaluated to meet the provisions of Draft Standard ISA Sd67.06, IEEE 338-1977, and NRC Guide 1.118. One in-situ method requires the perturbation of the high voltage detector (sensor) power supply and measurement of the sensor response. The response to a perturbation of the power supply is related to the response of the sensor to a transient change in neutron flux. Random signal analysis is another in-situ technique to monitor the neutron sensor response. In this method the power spectrum of the inherent fluctuations from the neutron sensor output (current in CIC) are measured and evaluated. Transient response techniques (including in-situ methods) are experimentally and analytically evaluated to identify the mechanisms which may cause degradation in the response of the neutron sensors. The objective of the experimental evaluation was to correlate the measured response time using transient radiation flux changes and power supply perturbation. The objective of the analytical model of the different sensor response was to predict response time and degradation mechanisms

Radar target classification method with high accuracy and decision speed performance using MUSIC spectrum vectors and PCA projection

Science.gov (United States)

Secmen, Mustafa

2011-10-01

This paper introduces the performance of an electromagnetic target recognition method in resonance scattering region, which includes pseudo spectrum Multiple Signal Classification (MUSIC) algorithm and principal component analysis (PCA) technique. The aim of this method is to classify an "unknown" target as one of the "known" targets in an aspect-independent manner. The suggested method initially collects the late-time portion of noise-free time-scattered signals obtained from different reference aspect angles of known targets. Afterward, these signals are used to obtain MUSIC spectrums in real frequency domain having super-resolution ability and noise resistant feature. In the final step, PCA technique is applied to these spectrums in order to reduce dimensionality and obtain only one feature vector per known target. In the decision stage, noise-free or noisy scattered signal of an unknown (test) target from an unknown aspect angle is initially obtained. Subsequently, MUSIC algorithm is processed for this test signal and resulting test vector is compared with feature vectors of known targets one by one. Finally, the highest correlation gives the type of test target. The method is applied to wire models of airplane targets, and it is shown that it can tolerate considerable noise levels although it has a few different reference aspect angles. Besides, the runtime of the method for a test target is sufficiently low, which makes the method suitable for real-time applications.

Response moments of dynamic systems under non-Gaussian random excitation by the equivalent non-Gaussian excitation method

International Nuclear Information System (INIS)

Tsuchida, Takahiro; Kimura, Koji

2016-01-01

Equivalent non-Gaussian excitation method is proposed to obtain the response moments up to the 4th order of dynamic systems under non-Gaussian random excitation. The non-Gaussian excitation is prescribed by the probability density and the power spectrum, and is described by an Ito stochastic differential equation. Generally, moment equations for the response, which are derived from the governing equations for the excitation and the system, are not closed due to the nonlinearity of the diffusion coefficient in the equation for the excitation even though the system is linear. In the equivalent non-Gaussian excitation method, the diffusion coefficient is replaced with the equivalent diffusion coefficient approximately to obtain a closed set of the moment equations. The square of the equivalent diffusion coefficient is expressed by a quadratic polynomial. In numerical examples, a linear system subjected to nonGaussian excitations with bimodal and Rayleigh distributions is analyzed by using the present method. The results show that the method yields the variance, skewness and kurtosis of the response with high accuracy for non-Gaussian excitation with the widely different probability densities and bandwidth. The statistical moments of the equivalent non-Gaussian excitation are also investigated to describe the feature of the method. (paper)

The application of thermoluminescence dosimeter on the measurement of hard X-ray pulse energy spectrum

International Nuclear Information System (INIS)

Song Zhaohui; Wang Baohui; Wang Kuilu; Hei Dongwei; Sun Fengrong; Li Gang

2001-01-01

This paper introduce the application of thermoluminescence dosimeter (TLD) which composed by TLD-3500 Reader and TLD-100M chips on the measurement of hard X-ray pulse energy spectrum. The idea, using Filter Fluorescence Method (FFM) and TLD to measure hard X-ray pulse energy spectrum (from 10 keV to 100 keV), is discussed in details. Considering all the factors of the measuring surroundings, the measurement system of hard X-ray pulse has been devised. The calibration technique of absolute energy response of TLD is established. This method has been applied successfully on the radiation parameters measurement of the huge pulse radiation device -high-power pulser I. Hard X-ray pulse energy spectrum data of the pulser are acquired

The finite element response Matrix method

International Nuclear Information System (INIS)

Nakata, H.; Martin, W.R.

1983-01-01

A new method for global reactor core calculations is described. This method is based on a unique formulation of the response matrix method, implemented with a higher order finite element method. The unique aspects of this approach are twofold. First, there are two levels to the overall calculational scheme: the local or assembly level and the global or core level. Second, the response matrix scheme, which is formulated at both levels, consists of two separate response matrices rather than one response matrix as is generally the case. These separate response matrices are seen to be quite beneficial for the criticality eigenvalue calculation, because they are independent of k /SUB eff/. The response matrices are generated from a Galerkin finite element solution to the weak form of the diffusion equation, subject to an arbitrary incoming current and an arbitrary distributed source. Calculational results are reported for two test problems, the two-dimensional International Atomic Energy Agency benchmark problem and a two-dimensional pressurized water reactor test problem (Biblis reactor), and they compare well with standard coarse mesh methods with respect to accuracy and efficiency. Moreover, the accuracy (and capability) is comparable to fine mesh for a fraction of the computational cost. Extension of the method to treat heterogeneous assemblies and spatial depletion effects is discussed

Spectrum recovery method based on sparse representation for segmented multi-Gaussian model

Science.gov (United States)

Teng, Yidan; Zhang, Ye; Ti, Chunli; Su, Nan

2016-09-01

Hyperspectral images can realize crackajack features discriminability for supplying diagnostic characteristics with high spectral resolution. However, various degradations may generate negative influence on the spectral information, including water absorption, bands-continuous noise. On the other hand, the huge data volume and strong redundancy among spectrums produced intense demand on compressing HSIs in spectral dimension, which also leads to the loss of spectral information. The reconstruction of spectral diagnostic characteristics has irreplaceable significance for the subsequent application of HSIs. This paper introduces a spectrum restoration method for HSIs making use of segmented multi-Gaussian model (SMGM) and sparse representation. A SMGM is established to indicating the unsymmetrical spectral absorption and reflection characteristics, meanwhile, its rationality and sparse property are discussed. With the application of compressed sensing (CS) theory, we implement sparse representation to the SMGM. Then, the degraded and compressed HSIs can be reconstructed utilizing the uninjured or key bands. Finally, we take low rank matrix recovery (LRMR) algorithm for post processing to restore the spatial details. The proposed method was tested on the spectral data captured on the ground with artificial water absorption condition and an AVIRIS-HSI data set. The experimental results in terms of qualitative and quantitative assessments demonstrate that the effectiveness on recovering the spectral information from both degradations and loss compression. The spectral diagnostic characteristics and the spatial geometry feature are well preserved.

A wavelet-based Gaussian method for energy dispersive X-ray fluorescence spectrum

Directory of Open Access Journals (Sweden)

Pan Liu

2017-05-01

Full Text Available This paper presents a wavelet-based Gaussian method (WGM for the peak intensity estimation of energy dispersive X-ray fluorescence (EDXRF. The relationship between the parameters of Gaussian curve and the wavelet coefficients of Gaussian peak point is firstly established based on the Mexican hat wavelet. It is found that the Gaussian parameters can be accurately calculated by any two wavelet coefficients at the peak point which has to be known. This fact leads to a local Gaussian estimation method for spectral peaks, which estimates the Gaussian parameters based on the detail wavelet coefficients of Gaussian peak point. The proposed method is tested via simulated and measured spectra from an energy X-ray spectrometer, and compared with some existing methods. The results prove that the proposed method can directly estimate the peak intensity of EDXRF free from the background information, and also effectively distinguish overlap peaks in EDXRF spectrum.

Auditory processing in autism spectrum disorder

DEFF Research Database (Denmark)

Vlaskamp, Chantal; Oranje, Bob; Madsen, Gitte Falcher

2017-01-01

Children with autism spectrum disorders (ASD) often show changes in (automatic) auditory processing. Electrophysiology provides a method to study auditory processing, by investigating event-related potentials such as mismatch negativity (MMN) and P3a-amplitude. However, findings on MMN in autism...... a hyper-responsivity at the attentional level. In addition, as similar MMN deficits are found in schizophrenia, these MMN results may explain some of the frequently reported increased risk of children with ASD to develop schizophrenia later in life. Autism Res 2017, 10: 1857–1865....

Stochastic shock response spectrum decomposition method based on probabilistic definitions of temporal peak acceleration, spectral energy, and phase lag distributions of mechanical impact pyrotechnic shock test data

Science.gov (United States)

Hwang, James Ho-Jin; Duran, Adam

2016-08-01

Most of the times pyrotechnic shock design and test requirements for space systems are provided in Shock Response Spectrum (SRS) without the input time history. Since the SRS does not describe the input or the environment, a decomposition method is used to obtain the source time history. The main objective of this paper is to develop a decomposition method producing input time histories that can satisfy the SRS requirement based on the pyrotechnic shock test data measured from a mechanical impact test apparatus. At the heart of this decomposition method is the statistical representation of the pyrotechnic shock test data measured from the MIT Lincoln Laboratory (LL) designed Universal Pyrotechnic Shock Simulator (UPSS). Each pyrotechnic shock test data measured at the interface of a test unit has been analyzed to produce the temporal peak acceleration, Root Mean Square (RMS) acceleration, and the phase lag at each band center frequency. Maximum SRS of each filtered time history has been calculated to produce a relationship between the input and the response. Two new definitions are proposed as a result. The Peak Ratio (PR) is defined as the ratio between the maximum SRS and the temporal peak acceleration at each band center frequency. The ratio between the maximum SRS and the RMS acceleration is defined as the Energy Ratio (ER) at each band center frequency. Phase lag is estimated based on the time delay between the temporal peak acceleration at each band center frequency and the peak acceleration at the lowest band center frequency. This stochastic process has been applied to more than one hundred pyrotechnic shock test data to produce probabilistic definitions of the PR, ER, and the phase lag. The SRS is decomposed at each band center frequency using damped sinusoids with the PR and the decays obtained by matching the ER of the damped sinusoids to the ER of the test data. The final step in this stochastic SRS decomposition process is the Monte Carlo (MC

Spectrum optimization-based chaotification using time-delay feedback control

International Nuclear Information System (INIS)

Zhou Jiaxi; Xu Daolin; Zhang Jing; Liu Chunrong

2012-01-01

Highlights: ► A time-delay feedback controller is designed for chaotification. ► A spectrum optimization method is proposed to determine chaotification parameters. ► Numerical examples verify the spectrum optimization- based chaotification method. ► Engineering application in line spectrum reconfiguration is demonstrated. - Abstract: In this paper, a spectrum optimization method is developed for chaotification in conjunction with an application in line spectrum reconfiguration. A key performance index (the objective function) based on Fourier spectrum is specially devised with the idea of suppressing spectrum spikes and broadening frequency band. Minimization of the index empowered by a genetic algorithm enables to locate favorable parameters of the time-delay feedback controller, by which a line spectrum of harmonic vibration can be transformed into a broad-band continuous spectrum of chaotic motion. Numerical simulations are carried out to verify the feasibility of the method and to demonstrate its effectiveness of chaotifying a 2-DOFs linear mechanical system.

A comparison in the reconstruction of neutron spectrums using classical iterative techniques

International Nuclear Information System (INIS)

Ortiz R, J. M.; Martinez B, M. R.; Vega C, H. R.; Gallego, E.

2009-10-01

One of the key drawbacks to the use of BUNKI code is that the process begins the reconstruction of the spectrum based on a priori knowledge as close as possible to the solution that is sought. The user has to specify the initial spectrum or do it through a subroutine called MAXIET to calculate a Maxwellian and a 1/E spectrum as initial spectrum. Because the application of iterative procedures by to resolve the reconstruction of neutron spectrum needs an initial spectrum, it is necessary to have new proposals for the election of the same. Based on the experience gained with a widely used method of reconstruction, called BUNKI, has developed a new computational tools for neutron spectrometry and dosimetry, which was first introduced, which operates by means of an iterative algorithm for the reconstruction of neutron spectra. The main feature of this tool is that unlike the existing iterative codes, the choice of the initial spectrum is performed automatically by the program, through a neutron spectra catalog. To develop the code, the algorithm was selected as the routine iterative SPUNIT be used in computing tool and response matrix UTA4 for 31 energy groups. (author)

Study of mixed programming gamma spectrum acquisition method based on MSP430F4618

International Nuclear Information System (INIS)

Li Yuezhong; Tang Bin; Zhang Zhongliang; Xie Xiaolin

2012-01-01

In order to reduce the hand-held gamma spectrometer measurements dead time and to complete the low-voltage and low-power design, the spectrum signal acquisition circuit is constituted by the ultra-low power microcontroller MSP430F4618 and its external signal conditioning circuit, anti-coincidence circuit interface and its on-chip sample hold and A/D converter. C language programming and assembly one have been used together. The sample hold and A/D conversion and spectrum acquisition programming is accomplished by assembly language, and the system monitoring and task scheduler designing is accomplished by C language programming. The handhold gamma spectrometer power supply, which just uses two No.5 rechargeable batteries, is designed by high-efficiency DC-DC circuit. The prototype gamma spectrometer is developed by the method, and its testing shows that the implementation of spectrum acquisition time is shorten by twice to 3 times, that is, the dead measurement can be reduced; and the machine operating current does not exceed 150 mA. By using two 2400 mAh No.5 rechargeable battery, the machine can work continuously more than 10 hours, and it can meet the application requirements. (authors)

Method to Reduce Long-lived Fission Products by Nuclear Transmutations with Fast Spectrum Reactors.

Science.gov (United States)

Chiba, Satoshi; Wakabayashi, Toshio; Tachi, Yoshiaki; Takaki, Naoyuki; Terashima, Atsunori; Okumura, Shin; Yoshida, Tadashi

2017-10-24

Transmutation of long-lived fission products (LLFPs: 79 Se, 93 Zr, 99 Tc, 107 Pd, 129 I, and 135 Cs) into short-lived or non-radioactive nuclides by fast neutron spectrum reactors without isotope separation has been proposed as a solution to the problem of radioactive wastes disposal. Despite investigation of many methods, such transmutation remains technologically difficult. To establish an effective and efficient transmutation system, we propose a novel neutron moderator material, yttrium deuteride (YD 2 ), to soften the neutron spectrum leaking from the reactor core. Neutron energy spectra and effective half-lives of LLFPs, transmutation rates, and support ratios were evaluated with the continuous-energy Monte Carlo code MVP-II/MVP-BURN and the JENDL-4.0 cross section library. With the YD 2 moderator in the radial blanket and shield regions, effective half-lives drastically decreased from 106 to 102 years and the support ratios reached 1.0 for all six LLFPs. This successful development and implementation of a transmutation system for LLFPs without isotope separation contributes to a the ability of fast spectrum reactors to reduce radioactive waste by consuming their own LLFPs.

Non-uniform sampling and wide range angular spectrum method

International Nuclear Information System (INIS)

Kim, Yong-Hae; Byun, Chun-Won; Oh, Himchan; Lee, JaeWon; Pi, Jae-Eun; Heon Kim, Gi; Lee, Myung-Lae; Ryu, Hojun; Chu, Hye-Yong; Hwang, Chi-Sun

2014-01-01

A novel method is proposed for simulating free space field propagation from a source plane to a destination plane that is applicable for both small and large propagation distances. The angular spectrum method (ASM) was widely used for simulating near field propagation, but it caused a numerical error when the propagation distance was large because of aliasing due to under sampling. Band limited ASM satisfied the Nyquist condition on sampling by limiting a bandwidth of a propagation field to avoid an aliasing error so that it could extend the applicable propagation distance of the ASM. However, the band limited ASM also made an error due to the decrease of an effective sampling number in a Fourier space when the propagation distance was large. In the proposed wide range ASM, we use a non-uniform sampling in a Fourier space to keep a constant effective sampling number even though the propagation distance is large. As a result, the wide range ASM can produce simulation results with high accuracy for both far and near field propagation. For non-paraxial wave propagation, we applied the wide range ASM to a shifted destination plane as well. (paper)

A Comparative Study between Codes of Spectrum for a Single Degree of Freedom (SDOF) System in Two Different Hazardous Regions

Energy Technology Data Exchange (ETDEWEB)

Pour, P Moradi; Noorzaei, J [Institute of Advanced Technology (ITMA), Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan (Malaysia); Karisiddappa [Vice Principal of Malnad College of Engineering, 573201 Hassan, Karnataka (India); Jaafar, M S, E-mail: jamal@eng.upm.edu.my [Department of Civil Engineering, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan (Malaysia)

2011-02-15

Since in structure and earthquake engineering design of structures using response spectrum method (RSM) is very important, this study has been performed for a single degree of freedom (SDOF) system. Firstly the concept and the way of construction of response spectrum has been briefly explained. Then the records of some strong earthquakes in USA and Iran as two hazardous regions have been plotted, after that selected response spectrums (RS) of each country has been compared with each other and finally with standard response code of its own country. It was concluded:1) For a given ground motion the response of a SDOF system only depends on its natural vibration period (T) and damping ratio({zeta}).2) When the effective damping ratio of a structure increases, its dynamic responses will decrease which demands the use of higher value of damping ratio in the structure. Also the FORTRAN computer programme for solving the Duhamel's Integral has been improved in this paper.

Proximal gamma-ray spectroscopy to predict soil properties using windows and full-spectrum analysis methods.

Science.gov (United States)

Mahmood, Hafiz Sultan; Hoogmoed, Willem B; van Henten, Eldert J

2013-11-27

Fine-scale spatial information on soil properties is needed to successfully implement precision agriculture. Proximal gamma-ray spectroscopy has recently emerged as a promising tool to collect fine-scale soil information. The objective of this study was to evaluate a proximal gamma-ray spectrometer to predict several soil properties using energy-windows and full-spectrum analysis methods in two differently managed sandy loam fields: conventional and organic. In the conventional field, both methods predicted clay, pH and total nitrogen with a good accuracy (R2 ≥ 0.56) in the top 0-15 cm soil depth, whereas in the organic field, only clay content was predicted with such accuracy. The highest prediction accuracy was found for total nitrogen (R2 = 0.75) in the conventional field in the energy-windows method. Predictions were better in the top 0-15 cm soil depths than in the 15-30 cm soil depths for individual and combined fields. This implies that gamma-ray spectroscopy can generally benefit soil characterisation for annual crops where the condition of the seedbed is important. Small differences in soil structure (conventional vs. organic) cannot be determined. As for the methodology, we conclude that the energy-windows method can establish relations between radionuclide data and soil properties as accurate as the full-spectrum analysis method.

Relativistic and thermal effects on the magnon spectrum of a ferromagnetic monolayer.

Science.gov (United States)

Rózsa, L; Udvardi, L; Szunyogh, L

2013-12-18

A spin model including magnetic anisotropy terms and Dzyaloshinsky-Moriya interactions is studied for the case of a ferromagnetic monolayer with C2v symmetry like Fe/W(110). Using the quasiclassical stochastic Landau-Lifshitz-Gilbert equations, the magnon spectrum of the system is derived using linear response theory. The Dzyaloshinsky-Moriya interaction leads to asymmetry in the spectrum, while the anisotropy terms induce a gap. It is shown that, in the presence of lattice defects, both the Dzyaloshinsky-Moriya interactions and the two-site anisotropy lead to a softening of the magnon energies. Two methods are developed to investigate the magnon spectrum at finite temperatures. The theoretical results are compared to atomistic spin dynamics simulations and good agreement is found between them.

Effects of a Multimedia Social Skills Program in Increasing Social Responses and Initiations of Children with Autism Spectrum Disorder

Science.gov (United States)

Block, Heidi M.; Radley, Keith C.; Jenson, William R.; Clark, Elaine; O'Neill, Robert E.

2015-01-01

The current study evaluated the effectiveness of Superheroes Social Skills, a multimedia social skills package, in improving social responsiveness and social initiation behaviors of four elementary school children with an autism spectrum disorder (ASD). The program was implemented in a public school setting in the southwestern United States for…

Associations between Language Development and Skin Conductance Responses to Faces and Eye Gaze in Children with Autism Spectrum Disorder

Science.gov (United States)

Stagg, Steven D.; Davis, Robert; Heaton, Pamela

2013-01-01

Attention to social stimuli is associated with language development, and arousal is associated with the increased viewing of stimuli. We investigated whether skin conductance responses (SCRs) are associated with language development in autism spectrum disorder (ASD): a population that shows abnormalities in both attention to others and language…

Carbon-13 NMR of glycogen: Hydration response studied by using solids methods

International Nuclear Information System (INIS)

Jackson, C.L.; Bryant, R.G.

1989-01-01

The carbon-13 NMR spectra of glycogen are reported by using the methods of magic-angle sample spinning and high-power proton decoupling to provide a dynamic report on the glucose monomer behavior as a function of hydration. Although the glycogen behaves as a typical polymer in the dry state, addition of water makes a significant difference in the spectral appearance. Water addition decreases the carbon spin-lattice relaxation times by 2 orders of magnitude over the range from 7% to 70% water by weight. The proton-carbon dipole-dipole coupling, which broadens the carbon spectrum and permits cross-polarization spectroscopy, is lost with increasing hydration over this range. By 60% water by weight, scalar decoupling methods are sufficient to achieve a reasonably high-resolution spectrum. Further, at this concentration, the carbon spin-lattice relaxation times are near their minimum values at a resonance frequency of 50.3 MHz, making acquisition of carbon spectra relatively insensitive to intensity distortions associated with saturation effects. Though motional averaging places the spectrum in the solution phase limit, the static spectrum shows a residual broader component that would not necessarily be detected readily by using high-resolution liquid-state experiments

Seismic analysis of a NPP reactor building using spectrum-compatible power spectral density functions

International Nuclear Information System (INIS)

Venancio Filho, F.; DeCarvalho Santos, S.H.; Joia, L.A.

1987-01-01

A numerical methodology to obtain Power Spectral Density Functions (PSDF) of ground accelerations, compatible with a given design response spectrum is presented. The PSDF's are derived from the statistical analysis of the amplitudes of the frequency components in a set of artificially generated time-histories matching the given spectrum. A so obtained PSDF is then used in the stochastic analysis of a NPP Reactor Building. The main results of this analysis are compared with the ones obtained by deterministic methods

Seismic analysis of a NPP reactor building using spectrum-compatible power spectral density functions

International Nuclear Information System (INIS)

Venancio Filho, F.; Joia, L.A.

1987-01-01

A numerical methodology to obtain Power Spectral Density Functions (PSDF) of ground accelerations, compatible with a given design response spectrum is presented. The PSDF's are derived from the statistical analysis of the amplitudes of the frequency components in a set of artificially generated time-histories matching the given spectrum. A so obtained PSDF is then used in the stochastic analysis of a reactor building. The main results of this analysis are compared with the ones obtained by deterministic methods. (orig./HP)

Instantaneous spectrum estimation of earthquake ground motions based on unscented Kalman filter method

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

Representing earthquake ground motion as time varying ARMA model, the instantaneous spectrum can only be determined by the time varying coefficients of the corresponding ARMA model. In this paper, unscented Kalman filter is applied to estimate the time varying coefficients. The comparison between the estimation results of unscented Kalman filter and Kalman filter methods shows that unscented Kalman filter can more precisely represent the distribution of the spectral peaks in time-frequency plane than Kalman filter, and its time and frequency resolution is finer which ensures its better ability to track the local properties of earthquake ground motions and to identify the systems with nonlinearity or abruptness. Moreover, the estimation results of ARMA models with different orders indicate that the theoretical frequency resolving power ofARMA model which was usually ignored in former studies has great effect on the estimation precision of instantaneous spectrum and it should be taken as one of the key factors in order selection of ARMA model.

A nodal method based on matrix-response method

International Nuclear Information System (INIS)

Rocamora Junior, F.D.; Menezes, A.

1982-01-01

A nodal method based in the matrix-response method, is presented, and its application to spatial gradient problems, such as those that exist in fast reactors, near the core - blanket interface, is investigated. (E.G.) [pt

Studies of the Raman Spectra of Cyclic and Acyclic Molecules: Combination and Prediction Spectrum Methods

Energy Technology Data Exchange (ETDEWEB)

Kim, Taijin; Assary, Rajeev S.; Marshall, Christopher L.; Gosztola, David J.; Curtiss, Larry A.; Stair, Peter C.

2012-04-02

A combination of Raman spectroscopy and density functional methods was employed to investigate the spectral features of selected molecules: furfural, 5-hydroxymethyl furfural (HMF), methanol, acetone, acetic acid, and levulinic acid. The computed spectra and measured spectra are in excellent agreement, consistent with previous studies. Using the combination and prediction spectrum method (CPSM), we were able to predict the important spectral features of two platform chemicals, HMF and levulinic acid.The results have shown that CPSM is a useful alternative method for predicting vibrational spectra of complex molecules in the biomass transformation process.

The unfolding of NaI(Tl) γ-ray spectrum based on maximum likelihood method

International Nuclear Information System (INIS)

Zhang Qingxian; Ge Liangquan; Gu Yi; Zeng Guoqiang; Lin Yanchang; Wang Guangxi

2011-01-01

NaI(Tl) detectors, having a good detection efficiency, are used to detect gamma rays in field surveys. But the poor energy resolution hinders their applications, despite the use of traditional methods to resolve the overlapped gamma-ray peaks. In this paper, the maximum likelihood (ML) solution is used to resolve the spectrum. The ML method,which is capable of decomposing the peaks in energy difference of over 2/3 FWHM, is applied to scale NaI(Tl) the spectrometer. The result shows that the net area is in proportion to the content of isotopes and the precision of scaling is better than the stripping ration method. (authors)

Importance of Vibronic Effects in the UV-Vis Spectrum of the 7,7,8,8-Tetracyanoquinodimethane Anion.

Science.gov (United States)

Tapavicza, Enrico; Furche, Filipp; Sundholm, Dage

2016-10-11

We present a computational method for simulating vibronic absorption spectra in the ultraviolet-visible (UV-vis) range and apply it to the 7,7,8,8-tetracyanoquinodimethane anion (TCNQ - ), which has been used as a ligand in black absorbers. Gaussian broadening of vertical electronic excitation energies of TCNQ - from linear-response time-dependent density functional theory produces only one band, which is qualitatively incorrect. Thus, the harmonic vibrational modes of the two lowest doublet states were computed, and the vibronic UV-vis spectrum was simulated using the displaced harmonic oscillator approximation, the frequency-shifted harmonic oscillator approximation, and the full Duschinsky formalism. An efficient real-time generating function method was implemented to avoid the exponential complexity of conventional Franck-Condon approaches to vibronic spectra. The obtained UV-vis spectra for TCNQ - agree well with experiment; the Duschinsky rotation is found to have only a minor effect on the spectrum. Born-Oppenheimer molecular dynamics simulations combined with calculations of the electronic excitation energies for a large number of molecular structures were also used for simulating the UV-vis spectrum. The Born-Oppenheimer molecular dynamics simulations yield a broadening of the energetically lowest peak in the absorption spectrum, but additional vibrational bands present in the experimental and simulated quantum harmonic oscillator spectra are not observed in the molecular dynamics simulations. Our results underline the importance of vibronic effects for the UV-vis spectrum of TCNQ - , and they establish an efficient method for obtaining vibronic spectra using a combination of linear-response time-dependent density functional theory and a real-time generating function approach.

Response matrix method for large LMFBR analysis

International Nuclear Information System (INIS)

King, M.J.

1977-06-01

The feasibility of using response matrix techniques for computational models of large LMFBRs is examined. Since finite-difference methods based on diffusion theory have generally found a place in fast-reactor codes, a brief review of their general matrix foundation is given first in order to contrast it to the general strategy of response matrix methods. Then, in order to present the general method of response matrix technique, two illustrative examples are given. Matrix algorithms arising in the application to large LMFBRs are discussed, and the potential of the response matrix method is explored for a variety of computational problems. Principal properties of the matrices involved are derived with a view to application of numerical methods of solution. The Jacobi iterative method as applied to the current-balance eigenvalue problem is discussed

A Mixed Methods Study of Barriers to Formal Diagnosis of Autism Spectrum Disorder in Adults

Science.gov (United States)

Lewis, Laura Foran

2017-01-01

Delayed diagnosis of autism spectrum disorder (ASD) into adulthood is common, and self-diagnosis is a growing phenomenon. This mixed methods study aimed to explore barriers to formal diagnosis of ASD in adults. In a qualitative strand, secondary analysis of data on the experiences of 114 individuals who were self-diagnosed or formally diagnosed…

Bloch walls and the non-ideal bose gas spectrum

International Nuclear Information System (INIS)

Vitiello, S.A.S.

1986-05-01

The quasi-particle spectrum of non-ideal Bose gas with domain walls in the condensate is investigated. The existence of such a system is determined from solutions of Gross-Pitaevskii equation which represent many-soliton systems. The walls which make the condensate non-uniform are responsible for density and velocity fields ρ(x) and υ(x) repectively. In the laboratory, the Bogoliubov spectrum, supposed to be true for an uniform condensate at rest, is changed due to the velocity field to which the quasi-particles are submited. The spectrum in the laboratory frame is obtained by considering the Galileu invariance principle and the interaction energy between the quasi-particle and its medium. The importance in considering the last two facts is illustrated by the analyse of a constant density condensate which moves uniformly in the laboratory. The many-soliton spectrum configuration and structure function are studied by the Monte Carlo method. In an approximation that assumes the quasi-particle to be point like, the condensate can be treated as locally uniform. For each event the position x of a quasi-particle and its momentum in a frame with velocity υ(x) are determined. Thus, by a convenient Galileu transformation the energy spectrum in the laboratory an be obtained. The results show a phonon spectrum which splits in two branches in the high momenta region. In this region the lower energy branch exibiths a point of minimum. Analogies with the He II are explored. (author) [pt

Generation of synthetic time histories compatible with multiple-damping design response spectra

International Nuclear Information System (INIS)

Lilhanand, K.; Tseng, W.S.

1987-01-01

Seismic design of nuclear power plants as currently practiced requires time history analyses be performed to generate floor response spectra for seismic qualification of piping, equipment, and components. Since design response spectra are normally prescribed in the form of smooth spectra, the generation of synthetic time histories whose response spectra closely match the ''target'' design spectra of multiple damping values, is often required for the seismic time history analysis purpose. Various methods of generation of synthetic time histories compatible with target response spectra have been proposed in the literature. Since the mathematical problem of determining a time history from a given set of response spectral values is not unique, an exact solution is not possible, and all the proposed methods resort to some forms of approximate solutions. In this paper, a new iteration scheme, is described which effectively removes the difficulties encountered by the existing methods. This new iteration scheme can not only improve the accuracy of spectrum matching for a single-damping target spectrum, but also automate the spectrum matching for multiple-damping target spectra. The applicability and limitations as well as the method adopted to improve the numerical stability of this new iteration scheme are presented. The effectiveness of this new iteration scheme is illustrated by two example applications

Do reward-processing deficits in schizophrenia-spectrum disorders promote cannabis use? An investigation of physiological response to natural rewards and drug cues

Science.gov (United States)

Cassidy, Clifford M.; Brodeur, Mathieu B.; Lepage, Martin; Malla, Ashok

2014-01-01

Background Dysfunctional reward processing is present in individuals with schizophrenia-spectrum disorders (SSD) and may confer vulnerability to addiction. Our objective was to identify a deficit in patients with SSD on response to rewarding stimuli and determine whether this deficit predicts cannabis use. Methods We divided a group of patients with SSD and nonpsychotic controls into cannabis users and nonusers. Response to emotional and cannabis-associated visual stimuli was assessed using self-report, event-related potentials (using the late positive potential [LPP]), facial electromyography and skin-conductance response. Results Our sample comprised 35 patients with SSD and 35 nonpsychotic controls. Compared with controls, the patients with SSD showed blunted LPP response to pleasant stimuli (p = 0.003). Across measures, cannabis-using controls showed greater response to pleasant stimuli than to cannabis stimuli whereas cannabis-using patients showed little bias toward pleasant stimuli. Reduced LPP response to pleasant stimuli was predictive of more frequent subsequent cannabis use (β = −0.24, p = 0.034). Limitations It is not clear if the deficit associated with cannabis use is specific to rewarding stimuli or nonspecific to any kind of emotionally salient stimuli. Conclusion The LPP captures a reward-processing deficit in patients with SSD and shows potential as a biomarker for identifying patients at risk of heavy cannabis use. PMID:24913137

Comparison of Saliva Collection Methods in Children with High-Functioning Autism Spectrum Disorders: Acceptability and Recovery of Cortisol

Science.gov (United States)

Putnam, Susan K.; Lopata, Christopher; Fox, Jeffery D.; Thomeer, Marcus L.; Rodgers, Jonathan D.; Volker, Martin A.; Lee, Gloria K.; Neilans, Erik G.; Werth, Jilynn

2012-01-01

This study compared cortisol concentrations yielded using three saliva collection methods (passive drool, salivette, and sorbette) in both in vitro and in vivo conditions, as well as method acceptability for a sample of children (n = 39) with High Functioning Autism Spectrum Disorders. No cortisol concentration differences were observed between…

Reconstructing Face Image from the Thermal Infrared Spectrum to the Visible Spectrum

Directory of Open Access Journals (Sweden)

Brahmastro Kresnaraman

2016-04-01

Full Text Available During the night or in poorly lit areas, thermal cameras are a better choice instead of normal cameras for security surveillance because they do not rely on illumination. A thermal camera is able to detect a person within its view, but identification from only thermal information is not an easy task. The purpose of this paper is to reconstruct the face image of a person from the thermal spectrum to the visible spectrum. After the reconstruction, further image processing can be employed, including identification/recognition. Concretely, we propose a two-step thermal-to-visible-spectrum reconstruction method based on Canonical Correlation Analysis (CCA. The reconstruction is done by utilizing the relationship between images in both thermal infrared and visible spectra obtained by CCA. The whole image is processed in the first step while the second step processes patches in an image. Results show that the proposed method gives satisfying results with the two-step approach and outperforms comparative methods in both quality and recognition evaluations.

Heart Rate Profiles of Children with and without Autism Spectrum Disorder in Response to Physical Play: A Preliminary Investigation

Science.gov (United States)

Breslin, Casey M.; Rudisill, Mary E.; Wadsworth, Danielle W.

2015-01-01

In this study, the heart rate response of children with and without autism spectrum disorder (ASD) exposed to outdoor free play sessions during preschool was examined. Participants (n = 7; four children with ASD and three children who show typical development) wore Actiheart heart rate monitors during 6 school days. Using a single-subject design,…

The finite element response matrix method

International Nuclear Information System (INIS)

Nakata, H.; Martin, W.R.

1983-02-01

A new technique is developed with an alternative formulation of the response matrix method implemented with the finite element scheme. Two types of response matrices are generated from the Galerkin solution to the weak form of the diffusion equation subject to an arbitrary current and source. The piecewise polynomials are defined in two levels, the first for the local (assembly) calculations and the second for the global (core) response matrix calculations. This finite element response matrix technique was tested in two 2-dimensional test problems, 2D-IAEA benchmark problem and Biblis benchmark problem, with satisfatory results. The computational time, whereas the current code is not extensively optimized, is of the same order of the well estabilished coarse mesh codes. Furthermore, the application of the finite element technique in an alternative formulation of response matrix method permits the method to easily incorporate additional capabilities such as treatment of spatially dependent cross-sections, arbitrary geometrical configurations, and high heterogeneous assemblies. (Author) [pt

Valuing spectrum at mm wavelengths for cellular networks

OpenAIRE

Shaw, B. A.; Beltrán, H. F.; Sowerby, K. W.

2017-01-01

This paper investigates the economic value of spectrum at mm wavelengths. The analysis uses four techniques to value spectrum, namely a benchmarking comparison, a discounted cash flow analysis, a real options approach and a deprival method. The methods to calculate spectrum value presented in this paper can be used for any spectrum band and in any country. However, to determine the value of mm wavelengths for cellular networks, we have used data from New Zealand, specifically for the existing...

Spectrally resolved, broadband frequency response characterization of photodetectors using continuous-wave supercontinuum sources

Science.gov (United States)

Choudhury, Vishal; Prakash, Roopa; Nagarjun, K. P.; Supradeepa, V. R.

2018-02-01

A simple and powerful method using continuous wave supercontinuum lasers is demonstrated to perform spectrally resolved, broadband frequency response characterization of photodetectors in the NIR Band. In contrast to existing techniques, this method allows for a simple system to achieve the goal, requiring just a standard continuous wave(CW) high-power fiber laser source and an RF spectrum analyzer. From our recent work, we summarize methods to easily convert any high-power fiber laser into a CW supercontinuum. These sources in the time domain exhibit interesting properties all the way down to the femtosecond time scale. This enables measurement of broadband frequency response of photodetectors while the wide optical spectrum of the supercontinuum can be spectrally filtered to obtain this information in a spectrally resolved fashion. The method involves looking at the RF spectrum of the output of a photodetector under test when incident with the supercontinuum. By using prior knowledge of the RF spectrum of the source, the frequency response can be calculated. We utilize two techniques for calibration of the source spectrum, one using a prior measurement and the other relying on a fitted model. Here, we characterize multiple photodetectors from 150MHz bandwidth to >20GHz bandwidth at multiple bands in the NIR region. We utilize a supercontinuum source spanning over 700nm bandwidth from 1300nm to 2000nm. For spectrally resolved measurement, we utilize multiple wavelength bands such as around 1400nm and 1600nm. Interesting behavior was observed in the frequency response of the photodetectors when comparing broadband spectral excitation versus narrower band excitation.

Beyond the Spectrum: Rethinking Autism

Directory of Open Access Journals (Sweden)

Heather Thomas

2017-03-01

Full Text Available The "spectrum" has become the dominant metaphor for conceptualizing autism, with fundamental consequences for notions of disability, diversity, and normality. In this article, we draw on ethnographic research with autistic communities to explore how the notion of the autism spectrum has become a focus of explicit identification, reflection, and contestation. To further this inquiry, we place these debates into conversation with earlier debates regarding another spectrum—the Kinsey Scale, a "spectrum" for conceptualizing sexual orientation that first appeared in 1948 but has been critiqued since the 1970s. How might responses to the Kinsey Scale (like the Klein Grid contribute to rethinking the autism spectrum? This is a question about the cultural and political implications of metaphors and conceptual models. It is of broad importance because the spectrum metaphor is being extended to a range of conditions beyond autism itself. Our goal is thus to build on insights from sexuality studies as well as the insights of autistic persons, advocates, and researchers who wish to forestall the naturalization of "the spectrum." In doing so, we seek to contribute to a discussion of what alternative frameworks might bring to questions of social justice, ability, and human flourishing.

Insight on agglomerates of gold nanoparticles in glass based on surface plasmon resonance spectrum: study by multi-spheres T-matrix method

Science.gov (United States)

Avakyan, L. A.; Heinz, M.; Skidanenko, A. V.; Yablunovski, K. A.; Ihlemann, J.; Meinertz, J.; Patzig, C.; Dubiel, M.; Bugaev, L. A.

2018-01-01

The formation of a localized surface plasmon resonance (SPR) spectrum of randomly distributed gold nanoparticles in the surface layer of silicate float glass, generated and implanted by UV ArF-excimer laser irradiation of a thin gold layer sputter-coated on the glass surface, was studied by the T-matrix method, which enables particle agglomeration to be taken into account. The experimental technique used is promising for the production of submicron patterns of plasmonic nanoparticles (given by laser masks or gratings) without damage to the glass surface. Analysis of the applicability of the multi-spheres T-matrix (MSTM) method to the studied material was performed through calculations of SPR characteristics for differently arranged and structured gold nanoparticles (gold nanoparticles in solution, particles pairs, and core-shell silver-gold nanoparticles) for which either experimental data or results of the modeling by other methods are available. For the studied gold nanoparticles in glass, it was revealed that the theoretical description of their SPR spectrum requires consideration of the plasmon coupling between particles, which can be done effectively by MSTM calculations. The obtained statistical distributions over particle sizes and over interparticle distances demonstrated the saturation behavior with respect to the number of particles under consideration, which enabled us to determine the effective aggregate of particles, sufficient to form the SPR spectrum. The suggested technique for the fitting of an experimental SPR spectrum of gold nanoparticles in glass by varying the geometrical parameters of the particles aggregate in the recurring calculations of spectrum by MSTM method enabled us to determine statistical characteristics of the aggregate: the average distance between particles, average size, and size distribution of the particles. The fitting strategy of the SPR spectrum presented here can be applied to nanoparticles of any nature and in various

Characteristics of Jerk Response Spectra for Elastic and Inelastic Systems

Directory of Open Access Journals (Sweden)

Haoxiang He

2015-01-01

Full Text Available Jerk is the time rate of acceleration and mainly represents the nonstationary component in high frequency band of the earthquake wave. The study on jerk and its response spectra can enhance the recognition of the nonstationary ground motion. The mechanical meaning and research value of jerk are described. Jerk is recommended to be solved by establishing state-space equations and Runge-Kutta method. The solution method of elastic and inelastic jerk response spectra under ground motion is established, and the accurate jerk spectrum should be calculated directly according to numerical computing instead of pseudo-acceleration spectrum. The characteristics of jerk response spectra are studied according to the influencing factors, such as site condition, amplification factor, ductility factor, and reduction factor. The concept of impact reduction factor is presented. The statistical results show that the jerk spectrum has similar rules as the acceleration spectrum, and the amplitude is relative to the predominant period, especially for structures with short or medium period. If the ductility is improved, the effective jerk will reduce obviously, and the impact reduction factor will be enhanced. Different from the strength reduction factor, the impact reduction factor is nearly not relevant to the period.

Learning spectrum's selection in OLAM network for analysis cement samples

International Nuclear Information System (INIS)

Huang Ning; Wang Peng; Tang Daiquan; Hu Renlan

2010-01-01

It uses OLAM artificial neural network to analyze the samples of cement raw material. Two kinds of spectrums are used for network learning: pure-element spectrum and mix-element spectrum. The output of pure-element method can be used to construct a simulate spectrum, which can be compared with the original spectrum and judge the shift of spectrum; the mix-element method can store more message and correct the matrix effect, but the multicollinearity among spectrums can cause some side effect to the results. (authors)

Methods for seismic analysis of nuclear power plants

International Nuclear Information System (INIS)

Gantenbein, F.

1990-01-01

The seismic analysis of a complex structure, such as a nuclear power plant, is done in various steps. An overview of the methods, used in each of these steps will be given in the following chapters: Seismic analysis of the buildings taking into account structures with important mass or stiffness. The input to the building analysis, called ground motion, is described by an accelerogram or a response spectra. In this step, soil structure interaction has to be taken into account. Various methods are available: Impedance, finite element. The response of the structure can be calculated by spectral method or by time history analysis; advantages and limitations of each method will be shown. Calculation of floor response spectrum which are the data for the equipment analysis. Methods to calculate this spectrum will be described. Seismic analysis of the equipments. Presentation of the methods for both monosupported and multisupported equipment will be given. In addition methods to analyse equipments which present non-linearities associated to the boundary conditions such as impacts, sliding will be presented. (author). 30 refs, 15 figs

Knowledge of Parents of Children with Autism Spectrum Disorder of Behavior Modification Methods and Their Training Needs Accordingly

Science.gov (United States)

Deeb, Raid Mousa Al-Shaik

2016-01-01

The study aimed at identifying knowledge of parents of children with autism spectrum disorder of behavior modification methods and their training needs accordingly. The sample of the study consisted of (98) parents in Jordan. A scale of behavior modification methods was constructed, and then validated. The results of the study showed that the…

ABOUT PROBABILITY OF RESEARCH OF THE NN Ser SPECTRUM BY MODEL ATMOSPHERES METHOD

OpenAIRE

Sakhibullin, N. A.; Shimansky, V. V.

2017-01-01

The spectrum of close binary system NN Ser is investigated by a models atmospheres method. It is show that the atmosphere near the centrum of a hot spot on surface of red dwarf has powerful chromospheres, arising from heating in Laiman continua. Four models of binary system with various of parameters are constructed and their theoretical spectra are obtained. Temperature of white dwarf Tef = 62000 K, radius of the red dwarf RT = 0.20139 and angle inclination of system i = 82“ are determined. ...

A revised method of presenting wavenumber-frequency power spectrum diagrams that reveals the asymmetric nature of tropical large-scale waves

Energy Technology Data Exchange (ETDEWEB)

Chao, Winston C. [NASA/Goddard Space Flight Center, Global Modeling and Assimilation Office, Mail Code 610.1, Greenbelt, MD (United States); Yang, Bo; Fu, Xiouhua [University of Hawaii at Manoa, School of Ocean and Earth Science and Technology, International Pacific Research Center, Honolulu, HI (United States)

2009-11-15

The popular method of presenting wavenumber-frequency power spectrum diagrams for studying tropical large-scale waves in the literature is shown to give an incomplete presentation of these waves. The so-called ''convectively coupled Kelvin (mixed Rossby-gravity) waves'' are presented as existing only in the symmetric (anti-symmetric) component of the diagrams. This is obviously not consistent with the published composite/regression studies of ''convectively coupled Kelvin waves,'' which illustrate the asymmetric nature of these waves. The cause of this inconsistency is revealed in this note and a revised method of presenting the power spectrum diagrams is proposed. When this revised method is used, ''convectively coupled Kelvin waves'' do show anti-symmetric components, and ''convectively coupled mixed Rossby-gravity waves (also known as Yanai waves)'' do show a hint of symmetric components. These results bolster a published proposal that these waves should be called ''chimeric Kelvin waves,'' ''chimeric mixed Rossby-gravity waves,'' etc. This revised method of presenting power spectrum diagrams offers an additional means of comparing the GCM output with observations by calling attention to the capability of GCMs to correctly simulate the asymmetric characteristics of equatorial waves. (orig.)

Neutron spectrum determination of d(20)+Be source reaction by the dosimetry foils method

Science.gov (United States)

Stefanik, Milan; Bem, Pavel; Majerle, Mitja; Novak, Jan; Simeckova, Eva

2017-11-01

The cyclotron-based fast neutron generator with the thick beryllium target operated at the NPI Rez Fast Neutron Facility is primarily designed for the fast neutron production in the p+Be source reaction at 35 MeV. Besides the proton beam, the isochronous cyclotron U-120M at the NPI provides the deuterons in the energy range of 10-20 MeV. The experiments for neutron field investigation from the deuteron bombardment of thick beryllium target at 20 MeV were performed just recently. For the neutron spectrum measurement of the d(20)+Be source reaction, the dosimetry foils activation method was utilized. Neutron spectrum reconstruction from resulting reaction rates was performed using the SAND-II unfolding code and neutron cross-sections from the EAF-2010 nuclear data library. Obtained high-flux white neutron field from the d(20)+Be source is useful for the intensive irradiation experiments and cross-section data validation.

An identification method of orbit responses rooting in vibration analysis of rotor during touchdowns of active magnetic bearings

Science.gov (United States)

Liu, Tao; Lyu, Mindong; Wang, Zixi; Yan, Shaoze

2018-02-01

Identification of orbit responses can make the active protection operation more easily realize for active magnetic bearings (AMB) in case of touchdowns. This paper presents an identification method of the orbit responses rooting on signal processing of rotor displacements during touchdowns. The recognition method consists of two major steps. Firstly, the combined rub and bouncing is distinguished from the other orbit responses by the mathematical expectation of axis displacements of the rotor. Because when the combined rub and bouncing occurs, the rotor of AMB will not be always close to the touchdown bearings (TDB). Secondly, we recognize the pendulum vibration and the full rub by the Fourier spectrum of displacement in horizontal direction, as the frequency characteristics of the two responses are different. The principle of the whole identification algorithm is illustrated by two sets of signal generated by a dynamic model of the specific rotor-TDB system. The universality of the method is validated by other four sets of signal. Besides, the adaptability of noise is also tested by adding white noises with different strengths, and the result is promising. As the mathematical expectation and Discrete Fourier transform are major calculations of the algorithm, the calculation quantity of the algorithm is low, so it is fast, easily realized and embedded in the AMB controller, which has an important engineering value for the protection of AMBs during touchdowns.

Can Autism Spectrum Disorders and Social Anxiety Disorders Be Differentiated by the Social Responsiveness Scale in Children and Adolescents?

Science.gov (United States)

Cholemkery, Hannah; Mojica, Laura; Rohrmann, Sonja; Gensthaler, Angelika; Freitag, Christine M.

2014-01-01

Autism spectrum disorder (ASD) as well as social phobia (SP), and selective mutism (SM) are characterised by impaired social interaction. We assessed the validity of the Social Responsiveness Scale (SRS) to differentiate between ASD, and SP/SM. Raw scores were compared in 6-18 year old individuals with ASD (N = 60), SP (N = 38), SM (N = 43), and…

Generation and reception of spread-spectrum signals

Science.gov (United States)

Moser, R.

1983-05-01

The term 'spread-spectrum' implies a technique whereby digitized information is added to a pseudo-random number sequence and the resultant bit stream changes some parameter of the carrier frequency in discrete increments. The discrete modulation of the carrier frequency is usually realized either as a multiple level phase shift keyed or frequency shift keyed signal. The resultant PSK-modulated frequency spectrum is referred to as direct sequence spread-spectrum, whereas the FSK-modulated carrier frequency is referred to as a frequency hopped spread spectrum. These can be considered the major subsets of the more general term 'spread-spectrum'. In discussing signal reception, it is pointed out that active correlation methods are used for channel synchronization when the psuedo random sequences are long or when the processing gain is large, whereas the passive methods may be used for either short pseudo-random noise generation codes or to assist in attaining initial synchronization in long sequence spread-spectrum systems.

Estimations of On-site Directional Wave Spectra from Measured Ship Responses

DEFF Research Database (Denmark)

Nielsen, Ulrik Dam

2006-01-01

include an quivalence of energy in the governing equations and, as regards the parametric concept, a frequency dependent spreading of the waves is introduced. The paper includes an extensive analysis of full-scale measurements for which the directional wave spectra are estimated by the two ship response......In general, two main concepts can be applied to estimate the on-site directional wave spectrum on the basis of ship response measurements: 1) a parametric method which assumes the wave spectrum to be composed by parameterised wave spectra, or 2) a non-parametric method where the directional wave...

Increasing Opportunities for Question-Asking in School-Aged Children with Autism Spectrum Disorder: Effectiveness of Staff Training in Pivotal Response Treatment

Science.gov (United States)

Verschuur, Rianne; Huskens, Bibi; Verhoeven, Ludo; Didden, Robert

2017-01-01

Deficits in question-asking are common in children with autism spectrum disorder (ASD). Furthermore, their opportunities to self-initiate questions are often hindered by directive behavior of their conversation partners. This study assessed the effectiveness of staff training in pivotal response treatment (PRT) on staff member-created…

Generation of floor response spectra for mixed-oxide fuel fabrication plants

International Nuclear Information System (INIS)

Arthur, D.F.; Murray, R.C.; Tokarz, F.J.

1975-01-01

Floor or amplified response spectra are generally used as input motion for seismic analysis of critical equipment and piping in nuclear power plants and related facilities. The floor spectra are normally the result of a time-history calculation of building response to ground shaking. However, alternate approximate methods have been suggested by both Kapur and Biggs. As part of a study for the Nuclear Regulatory Commission horizontal floor response spectra were generated and compared by all three methods. The dynamic analyses were performed on a model of the Westinghouse Recycle Fuels Plant Manufacturing Building (MOFFP). Input to the time-history calculations was a synthesized accelerogram whose response spectrum is similar to that in Regulatory Guide 1.60. The response spectrum of the synthetic ground motion was used as input to the Kapur and Biggs methods. Calculations were performed for both hard (3500 fps) and soft (1500 fps) foundation soils. Results of comparison of the three methods indicate that although the approximate methods could easily be made acceptable from a safety standpoint, they would be overly conservative. The time-history method will yield floor spectra which are less uncertain and less conservative for a relatively modest additional effort. (auth)

The Influence of Maternal Language Responsiveness on the Expressive Speech Production of Children with Autism Spectrum Disorders: A Microanalysis of Mother-Child Play Interactions

Science.gov (United States)

Walton, Katherine M.; Ingersoll, Brooke R.

2015-01-01

Adult responsiveness is related to language development both in young typically developing children and in children with autism spectrum disorders, such that parents who use more responsive language with their children have children who develop better language skills over time. This study used a micro-analytic technique to examine how two facets…

Finite element random vibration method for soil-structure interaction analysis

International Nuclear Information System (INIS)

Romo-Organista, M.P.; Lysmer, J.; Seed, H.B.

1977-01-01

The authors present a method in which the seismic environment is defined directly in terms of the given design response spectrum. Response spectra cannot be used directly for random analysis, thus using extreme value theory a new procedure has been developed for converting the design response spectrum into a design power spectrum. This procedure is reversible and can also be used to compute response spectra the distribution of which can be expressed in terms of Confidence limits. Knowing the design power spctrum the resulting output power spectra and their statistical distribution can be computed by a response analysis of the soil-structure system in the frequency domain. Due to the complexity of soil structure systems, this is most conveniently done by the finite element method. Having obtained the power spectra for all motions in the system, these spectra can be used to determine other statistical information about the response such as maximum accelerations, stresses, bending moments, etc, all with appropriate confidence limits. This type of information is actually more useful for design than corresponding deterministic values. The authors have developed a computer program, PLUSH, which can perform the above procedures. Results obtained by the new method are in excellent agreement with the results of corresponding deterministic analysis. Furthermore, the probabilistic results can be obtained at a fraction of the cost of deterministic results

Calibration-free absolute frequency response measurement of directly modulated lasers based on additional modulation.

Science.gov (United States)

Zhang, Shangjian; Zou, Xinhai; Wang, Heng; Zhang, Yali; Lu, Rongguo; Liu, Yong

2015-10-15

A calibration-free electrical method is proposed for measuring the absolute frequency response of directly modulated semiconductor lasers based on additional modulation. The method achieves the electrical domain measurement of the modulation index of directly modulated lasers without the need for correcting the responsivity fluctuation in the photodetection. Moreover, it doubles measuring frequency range by setting a specific frequency relationship between the direct and additional modulation. Both the absolute and relative frequency response of semiconductor lasers are experimentally measured from the electrical spectrum of the twice-modulated optical signal, and the measured results are compared to those obtained with conventional methods to check the consistency. The proposed method provides calibration-free and accurate measurement for high-speed semiconductor lasers with high-resolution electrical spectrum analysis.

Brain Responses Underlying Anthropomorphism, Agency, and Social Attribution in Autism Spectrum Disorder.

Science.gov (United States)

Ammons, Carla J; Doss, Constance F; Bala, David; Kana, Rajesh K

2018-01-01

Theory of Mind (ToM), the ability to attribute mental states to oneself and others, is frequently impaired in Autism Spectrum Disorder (ASD) and may result from altered activation of social brain regions. Conversely, Typically Developing (TD) individuals overextend ToM and show a strong tendency to anthropomorphize and interpret biological motion in the environment. Less is known about how the degree of anthropomorphism influences intentional attribution and engagement of the social brain in ASD. This fMRI study examines the extent of anthropomorphism, its role in social attribution, and the underlying neural responses in ASD and TD using a series of human stick figures and geometrical shapes. 14 ASD and 14 TD adults watched videos of stick figures and triangles interacting in random or socially meaningful ways while in an fMRI scanner. In addition, they completed out-of-scanner measures of ToM skill and real-world social deficits. Whole brain statistical analysis was performed for regression and within and between group comparisons of all conditions using SPM12's implementation of the general linear model. ToM network regions were activated in response to social movement and human-like characters in ASD and TD. In addition, greater ToM ability was associated with increased TPJ and MPFC activity while watching stick figures; whereas more severe social symptoms were associated with reduced right TPJ activation in response to social movement. These results suggest that degree of anthropomorphism does not differentially affect social attribution in ASD and highlights the importance of TPJ in ToM and social attribution.

A Mixed-Method Evaluation of the Feasibility and Acceptability of a Telehealth-Based Parent-Mediated Intervention for Children with Autism Spectrum Disorder

Science.gov (United States)

Pickard, Katherine E.; Wainer, Allison L.; Bailey, Kathryn M.; Ingersoll, Brooke R.

2016-01-01

Research within the autism spectrum disorder field has called for the use of service delivery models that are able to more efficiently disseminate evidence-based practices into community settings. This study employed telehealth methods in order to deliver an Internet-based, parent training intervention for autism spectrum disorder, ImPACT Online.…

Theoretical research relating to excitation spectrum of furan. Application of integral direct coupled cluster linear response (direct CCLR) method; Furan no reiki supekutoru ni kansuru ronriteki kenkyu. Integral-direct Coupled Cluster Linear Response (direct CCLR) ho no tekiyo

Energy Technology Data Exchange (ETDEWEB)

Shigemitsu, Yasuhiro. [Nagasaki Industrial Technology Center, Nagasaki (Japan)

1999-07-01

heoretical researches relating to excitation spectrum of furan have been carried out for many years, and they reveal the problems that should be solved in order to predict highly reliable excitation energy. In general, it is difficult to uniformly obtain highly reliable calculation results for all excitation states since different excitation states show different electronic correlative effects. Means for obtaining the electron states in ground state and excited state and calculating the energy difference thereof is the mainstream of the theoretical calculation of the excitation energy. CASSCF/CASPT 2 developed by Roos et al. is a typical method excellent in quantitative description. Recently, the comparison between direct CCLR and CASSCF/CASPT 2 as examples for calculating the excitation spectrum of furan was carried out by using the same ground function. For Rydberg excitation, CC3, CAS, CASPT 2 show good agreement with each other. (NEDO)

The Effect of Pivotal Response Treatment in Children with Autism Spectrum Disorders: A Non-randomized Study with a Blinded Outcome Measure

NARCIS (Netherlands)

Duifhuis, E.A.; Boer, J.C. den; Doornbos, A.; Buitelaar, J.K.; Oosterling, I.J.; Klip, H.

2017-01-01

Purpose of this quasi-experimental trial was to investigate the effect of Pivotal response treatment (PRT) versus treatment as usual (TAU) on autism symptoms. Children with autism spectrum disorder (ASD), aged 3-8 years, received either PRT (n = 11) or TAU (n = 13). Primary outcome measure was the

Electrostatic resonances and optical responses of cylindrical clusters

International Nuclear Information System (INIS)

Choy, C W; Xiao, J J; Yu, K W

2008-01-01

We developed a Green function formalism (GFF) for computing the electrostatic resonance in clusters of cylindrical particles. In the GFF, we take advantage of a surface integral equation to avoid matching the complicated boundary conditions on the surfaces of the particles. Numerical solutions of the eigenvalue equation yield a pole spectrum in the spectral representation. The pole spectrum can in turn be used to compute the optical response of these particles. For two cylindrical particles, the results are in excellent agreement with the exact results from the multiple image method and the normal mode expansion method. The results of this work can be extended to investigate the enhanced nonlinear optical responses of metal-dielectric composites, as well as optical switching in plasmonic waveguides.

The influence of campus experiences on the level of outness among trans-spectrum and queer-spectrum students.

Science.gov (United States)

Garvey, Jason C; Rankin, Susan R

2015-01-01

This study utilized MANOVA and hierarchical multiple regression to examine the relationships between campus experiences and coming-out decisions among trans- and queer-spectrum undergraduates. Findings revealed higher levels of outness/disclosure for cisgender LGBQ women, and more negative perceptions of campus climate, classroom climate, and curriculum inclusivity and higher use of campus resources for trans-spectrum students. Results also revealed that higher levels of outness significantly related to poorer perceptions of campus responses and campus resources. Implications address the need to foster an encouraging and supportive campus and classroom climate and to improve the relationships with LGBTQ resource centers for trans- and queer-spectrum students.

Gamma ray spectrum analysis code: sigmas 1.0

International Nuclear Information System (INIS)

Siangsanan, P.; Dharmavanij, W.; Chongkum, S.

1996-01-01

We have developed Sigmas 1.0 a software package for data reduction and gamma ray spectra evaluation. It is capable of analysing the gamma-ray spectrum in the range of 0-3 MeV by semiconductor detector, i.e. Ge(Li) or HPGe, peak searching, net area determining, plotting and spectrum displaying. There are two methods for calculating the net area under peaks; the Covell method and non-linear fitting by the method of Levenberg and Marquardt which can fit any multiplet peak in the spectrum. The graphic display was rather fast and user friendly

A Decentralized Eigenvalue Computation Method for Spectrum Sensing Based on Average Consensus

Science.gov (United States)

Mohammadi, Jafar; Limmer, Steffen; Stańczak, Sławomir

2016-07-01

This paper considers eigenvalue estimation for the decentralized inference problem for spectrum sensing. We propose a decentralized eigenvalue computation algorithm based on the power method, which is referred to as generalized power method GPM; it is capable of estimating the eigenvalues of a given covariance matrix under certain conditions. Furthermore, we have developed a decentralized implementation of GPM by splitting the iterative operations into local and global computation tasks. The global tasks require data exchange to be performed among the nodes. For this task, we apply an average consensus algorithm to efficiently perform the global computations. As a special case, we consider a structured graph that is a tree with clusters of nodes at its leaves. For an accelerated distributed implementation, we propose to use computation over multiple access channel (CoMAC) as a building block of the algorithm. Numerical simulations are provided to illustrate the performance of the two algorithms.

The Spectrum of the Universe.

Science.gov (United States)

Hill, Ryley; Masui, Kiyoshi W; Scott, Douglas

2018-05-01

Cosmic background (CB) radiation, encompassing the sum of emission from all sources outside our own Milky Way galaxy across the entire electromagnetic spectrum, is a fundamental phenomenon in observational cosmology. Many experiments have been conceived to measure it (or its constituents) since the extragalactic Universe was first discovered; in addition to estimating the bulk (cosmic monopole) spectrum, directional variations have also been detected over a wide range of wavelengths. Here we gather the most recent of these measurements and discuss the current status of our understanding of the CB from radio to γ-ray energies. Using available data in the literature, we piece together the sky-averaged intensity spectrum and discuss the emission processes responsible for what is observed. We examine the effect of perturbations to the continuum spectrum from atomic and molecular line processes and comment on the detectability of these signals. We also discuss how one could, in principle, obtain a complete census of the CB by measuring the full spectrum of each spherical harmonic expansion coefficient. This set of spectra of multipole moments effectively encodes the entire statistical history of nuclear, atomic, and molecular processes in the Universe.

Earthquake response of inelastic structures

International Nuclear Information System (INIS)

Parulekar, Y.M.; Vaity, K.N.; Reddy, .R.; Vaze, K.K.; Kushwaha, H.S.

2004-01-01

The most commonly used method in the seismic analysis of structures is the response spectrum method. For seismic re-evaluation of existing facilities elastic response spectrum method cannot be used directly as large deformation above yield may be observed under Safe Shutdown Earthquake (SSE). The plastic deformation, i.e. hysteretic characteristics of various elements of the structure cause dissipation of energy. Hence the values of damping given by the code, which does not account hysteretic energy dissipation cannot be directly used. In this paper, appropriate damping values are evaluated for 5-storey, 10-storey and 15-storey shear beam structures, which deform beyond their yield limit. Linear elastic analysis is performed for the same structures using these damping values and the storey forces are compared with those obtained using inelastic time history analysis. A damping model, which relates ductility of the structure and damping, is developed. Using his damping model, a practical structure is analysed and results are compared with inelastic time history analysis and the comparison is found to be good

The method of joint drawing in the practice of teaching drawing to the elementary school children with autism spectrum disorders

Directory of Open Access Journals (Sweden)

Belyalova O.A.

2015-06-01

Full Text Available While teaching children with autism spectrum disorders how to draw the teacher needs to focus on the fact that each child has creative potential and art activities play important part in the brain development. Often children diagnosed with autism spectrum disorder have serious speech impairments, for example, they can talk to parents and family members, but not to classmates and teachers. In that case, one can communicate with a child through drawings, and to access their mood and desires through them. The article describes the method of joint drawing during teaching elementary school children with autism spectrum disorders from the school at the Center for Psychological, Medical and Social Support to Children and Adolescents.

Dynamic selection of ship responses for estimation of on-site directional wave spectra

DEFF Research Database (Denmark)

Andersen, Ingrid Marie Vincent; Storhaug, Gaute

2012-01-01

-estimate of the wave spectrum is suggested. The selection method needs to be robust for what reason a parameterised uni-directional, two-parameter wave spectrum is treated. The parameters included are the zero up-crossing period, the significant wave height and the main wave direction relative to the ship’s heading...... with the best overall agreement are selected for the actual estimation of the directional wave spectrum. The transfer functions for the ship responses can be determined using different computational methods such as striptheory, 3D panel codes, closed form expressions or model tests. The uncertainty associated......Knowledge of the wave environment in which a ship is operating is crucial for most on-board decision support systems. Previous research has shown that the directional wave spectrum can be estimated by the use of measured global ship responses and a set of transfer functions determined...

A new method for detection of the electron temperature in laser-plasma short wave cut off of stimulated Raman scattering spectrum

International Nuclear Information System (INIS)

Zhang Jiatai

1994-01-01

From the theory of stimulated Raman scattering (SRS) three wave interaction, a new method of detecting the electron temperature in laser-plasma is obtained. SRS spectrum obtained from Shenguang No. 12 Nd-laser experiments are analysed. Using the wave length of short wave cut off of SRS, the electron temperature in corona plasma region is calculated consistently. These results agree reasonable with X-ray spectrum experiments

Novel Maximum-based Timing Acquisition for Spread-Spectrum Communications

Energy Technology Data Exchange (ETDEWEB)

Sibbetty, Taylor; Moradiz, Hussein; Farhang-Boroujeny, Behrouz

2016-12-01

This paper proposes and analyzes a new packet detection and timing acquisition method for spread spectrum systems. The proposed method provides an enhancement over the typical thresholding techniques that have been proposed for direct sequence spread spectrum (DS-SS). The effective implementation of thresholding methods typically require accurate knowledge of the received signal-to-noise ratio (SNR), which is particularly difficult to estimate in spread spectrum systems. Instead, we propose a method which utilizes a consistency metric of the location of maximum samples at the output of a filter matched to the spread spectrum waveform to achieve acquisition, and does not require knowledge of the received SNR. Through theoretical study, we show that the proposed method offers a low probability of missed detection over a large range of SNR with a corresponding probability of false alarm far lower than other methods. Computer simulations that corroborate our theoretical results are also presented. Although our work here has been motivated by our previous study of a filter bank multicarrier spread-spectrum (FB-MC-SS) system, the proposed method is applicable to DS-SS systems as well.

Experimental Validation of Ex-Vessel Neutron Spectrum by Means of Dosimeter Materials Activation Method

Directory of Open Access Journals (Sweden)

S.A. Santa

2017-06-01

Full Text Available Neutron spectrum information in reactor core and around of ex-vessel reactor needs to be known with a certain degree of accuracy to support the development of fuels, materials, and other components. The most common method to determine neutron spectra is by utilizing the radioactivation of dosimeter materials. This report presents the evaluation of neutron flux incident on M3dosimeter sets which were irradiated outside the reactor vessel,as well as the validation of  neutron spectrum calculation. Al capsules containing both dosimeter set covered withCd and dosimeter set without Cd cover have been irradiated during the 35th operational cycle in the M3 ex-vessel irradiation hole position207 cmfrom core centerline at the space between the reactor vessel and the safety vessel. The capsules were positioned at Z=0.0 cm of core midplane. Each dosimeter set consists of Co-Al, Sc, Fe, Np, Nb, Ni, B, and Ta. The gamma-ray spectra of irradiated dosimeter materials were measured by 63 cc HPGe solid-state detector and photo-peak spectra were analyzed using BOB75 code. The reaction rates of each dosimeter materials and its uncertainty were analyzed based on 59Co (n,g 60Co, 237Np (n,f 95Zr-103Ru,  45Sc (n,g 46Sc, 58Fe (n,g 59Fe, 181Ta (n,g 182Ta, and 58Ni (n,p58Co reactions. The measured Cd ratios indicate that neutron spectrum at the irradiated dosimeter sets was dominated by low energy neutron. The experimental result shows that the calculated neutron spectra by DORT code at the ex-vessel positions need correction, especially in the fast neutron energy region, so as to obtain reasonable unfolding result consistent with the reaction rate measurement without any exception. Using biased DORT initial spectrum, the neutron spectrum and its integral quantity were unfolded by NEUPAC code. The result shows that total neutron flux, flux above 1.0 MeV, flux above 0.1 MeV, and the displacement rate of the dosimeter set not covered with Cd were 1.75× 1012 n cm2 s-1, 1

Seismic response analysis of soil-structure interactive system using a coupled three-dimensional FE-IE method

International Nuclear Information System (INIS)

Ryu, Jeong-Soo; Seo, Choon-Gyo; Kim, Jae-Min; Yun, Chung-Bang

2010-01-01

This paper proposes a slightly new three-dimensional radial-shaped dynamic infinite elements fully coupled to finite elements for an analysis of soil-structure interaction system in a horizontally layered medium. We then deal with a seismic analysis technique for a three-dimensional soil-structure interactive system, based on the coupled finite-infinite method in frequency domain. The dynamic infinite elements are simulated for the unbounded domain with wave functions propagating multi-generated wave components. The accuracy of the dynamic infinite element and effectiveness of the seismic analysis technique may be demonstrated through a typical compliance analysis of square surface footing, an L-shaped mat concrete footing on layered soil medium and two kinds of practical seismic analysis tests. The practical analyses are (1) a site response analysis of the well-known Hualien site excited by all travelling wave components (primary, shear, Rayleigh waves) and (2) a generation of a floor response spectrum of a nuclear power plant. The obtained dynamic results show good agreement compared with the measured response data and numerical values of other soil-structure interaction analysis package.

A novel power harmonic analysis method based on Nuttall-Kaiser combination window double spectrum interpolated FFT algorithm

Science.gov (United States)

Jin, Tao; Chen, Yiyang; Flesch, Rodolfo C. C.

2017-11-01

Harmonics pose a great threat to safe and economical operation of power grids. Therefore, it is critical to detect harmonic parameters accurately to design harmonic compensation equipment. The fast Fourier transform (FFT) is widely used for electrical popular power harmonics analysis. However, the barrier effect produced by the algorithm itself and spectrum leakage caused by asynchronous sampling often affects the harmonic analysis accuracy. This paper examines a new approach for harmonic analysis based on deducing the modifier formulas of frequency, phase angle, and amplitude, utilizing the Nuttall-Kaiser window double spectrum line interpolation method, which overcomes the shortcomings in traditional FFT harmonic calculations. The proposed approach is verified numerically and experimentally to be accurate and reliable.

Optimization of the beam shaping assembly in the D-D neutron generators-based BNCT using the response matrix method.

Science.gov (United States)

Kasesaz, Y; Khalafi, H; Rahmani, F

2013-12-01

Optimization of the Beam Shaping Assembly (BSA) has been performed using the MCNP4C Monte Carlo code to shape the 2.45 MeV neutrons that are produced in the D-D neutron generator. Optimal design of the BSA has been chosen by considering in-air figures of merit (FOM) which consists of 70 cm Fluental as a moderator, 30 cm Pb as a reflector, 2mm (6)Li as a thermal neutron filter and 2mm Pb as a gamma filter. The neutron beam can be evaluated by in-phantom parameters, from which therapeutic gain can be derived. Direct evaluation of both set of FOMs (in-air and in-phantom) is very time consuming. In this paper a Response Matrix (RM) method has been suggested to reduce the computing time. This method is based on considering the neutron spectrum at the beam exit and calculating contribution of various dose components in phantom to calculate the Response Matrix. Results show good agreement between direct calculation and the RM method. Copyright © 2013 Elsevier Ltd. All rights reserved.

The method in γ spectrum analysis with artificial neural network based on MATLAB

International Nuclear Information System (INIS)

Bai Lixin; Zhang Yiyun; Xu Jiayun; Wu Liping

2003-01-01

Analyzing γ spectrum with artificial neural network have the advantage of using the information of whole spectrum and having high analyzing precision. A convenient realization based on MATLAB was present in this

A novel neutron energy spectrum unfolding code using particle swarm optimization

International Nuclear Information System (INIS)

Shahabinejad, H.; Sohrabpour, M.

2017-01-01

A novel neutron Spectrum Deconvolution using Particle Swarm Optimization (SDPSO) code has been developed to unfold the neutron spectrum from a pulse height distribution and a response matrix. The Particle Swarm Optimization (PSO) imitates the bird flocks social behavior to solve complex optimization problems. The results of the SDPSO code have been compared with those of the standard spectra and recently published Two-steps Genetic Algorithm Spectrum Unfolding (TGASU) code. The TGASU code have been previously compared with the other codes such as MAXED, GRAVEL, FERDOR and GAMCD and shown to be more accurate than the previous codes. The results of the SDPSO code have been demonstrated to match well with those of the TGASU code for both under determined and over-determined problems. In addition the SDPSO has been shown to be nearly two times faster than the TGASU code. - Highlights: • Introducing a novel method for neutron spectrum unfolding. • Implementation of a particle swarm optimization code for neutron unfolding. • Comparing results of the PSO code with those of recently published TGASU code. • Match results of the PSO code with those of TGASU code. • Greater convergence rate of implemented PSO code than TGASU code.

A comparative study of amplitude calibrations for the East Asia VLBI Network: A priori and template spectrum methods

Science.gov (United States)

Cho, Ilje; Jung, Taehyun; Zhao, Guang-Yao; Akiyama, Kazunori; Sawada-Satoh, Satoko; Kino, Motoki; Byun, Do-Young; Sohn, Bong Won; Shibata, Katsunori M.; Hirota, Tomoya; Niinuma, Kotaro; Yonekura, Yoshinori; Fujisawa, Kenta; Oyama, Tomoaki

2017-12-01

We present the results of a comparative study of amplitude calibrations for the East Asia VLBI Network (EAVN) at 22 and 43 GHz using two different methods of an "a priori" and a "template spectrum", particularly on lower declination sources. Using observational data sets of early EAVN observations, we investigated the elevation-dependence of the gain values at seven stations of the KaVA (KVN and VERA Array) and three additional telescopes in Japan (Takahagi 32 m, Yamaguchi 32 m, and Nobeyama 45 m). By comparing the independently obtained gain values based on these two methods, we found that the gain values from each method were consistent within 10% at elevations higher than 10°. We also found that the total flux densities of two images produced from the different amplitude calibrations were in agreement within 10% at both 22 and 43 GHz. By using the template spectrum method, furthermore, the additional radio telescopes can participate in KaVA (i.e., EAVN), giving a notable sensitivity increase. Therefore, our results will constrain the detailed conditions in order to measure the VLBI amplitude reliably using EAVN, and discuss the potential of possible expansion to telescopes comprising EAVN.

An artificial solar spectrum substantially alters plant development compared with usual climate room irradiance spectra.

Science.gov (United States)

Hogewoning, Sander W; Douwstra, Peter; Trouwborst, Govert; van Ieperen, Wim; Harbinson, Jeremy

2010-03-01

Plant responses to the light spectrum under which plants are grown affect their developmental characteristics in a complicated manner. Lamps widely used to provide growth irradiance emit spectra which are very different from natural daylight spectra. Whereas specific responses of plants to a spectrum differing from natural daylight may sometimes be predictable, the overall plant response is generally difficult to predict due to the complicated interaction of the many different responses. So far studies on plant responses to spectra either use no daylight control or, if a natural daylight control is used, it will fluctuate in intensity and spectrum. An artificial solar (AS) spectrum which closely resembles a sunlight spectrum has been engineered, and growth, morphogenesis, and photosynthetic characteristics of cucumber plants grown for 13 d under this spectrum have been compared with their performance under fluorescent tubes (FTs) and a high pressure sodium lamp (HPS). The total dry weight of the AS-grown plants was 2.3 and 1.6 times greater than that of the FT and HPS plants, respectively, and the height of the AS plants was 4-5 times greater. This striking difference appeared to be related to a more efficient light interception by the AS plants, characterized by longer petioles, a greater leaf unfolding rate, and a lower investment in leaf mass relative to leaf area. Photosynthesis per leaf area was not greater for the AS plants. The extreme differences in plant response to the AS spectrum compared with the widely used protected cultivation light sources tested highlights the importance of a more natural spectrum, such as the AS spectrum, if the aim is to produce plants representative of field conditions.

Photon-response spectrum of surface barrier diodes on GaAssub(1-x)Psub(x) mixed crystals

International Nuclear Information System (INIS)

Omar, O.A.

1981-07-01

Surface barrier diodes have been prepared by chemical deposition of thin gold film on samples of GaAssub(1-x)Psub(x) with x=0.3. The spectrum of the photo-response over a spectral range covering the photo-injection from the metal and the intrinsic absorption regions of the semiconductor has been measured. From the photo-threshold corresponding to each region, the height of the energy barrier and the forbidden gap width of the semiconductor have been determined and are found to be 0.96 e.v. and 1.78 e.v. respectively for the investigated composition. (author)

Response function study of a scintillator detector of NaI(Tl)

International Nuclear Information System (INIS)

Villa, Marcelo Barros; Costa, Alessandro Martins da

2014-01-01

In measurements of gamma rays with Nai (Tl) scintillator, the detectors output data are pulse height spectra, that corresponding to distorted information about the radiation source due to various errors associated with the crystal scintillation process and electronics associated, instead of power spectra photons. Pulse height spectra are related to the real power spectra by means of scintillator detector response function NaI (Tl). In this work, the response function for a cylindrical crystal of Nal (Tl) of 7,62 x 7,62 cm (diameter x length) was studied, by Monte Carlo method, using the EGSnrc tool to model the transport of radiation, combined with experimental measurements. An inverse response matrix, even with the energy of the square root, which transforms the pulse height spectrum of photon energy spectrum was obtained. The results of this transformation of pulse height spectrum for photon energy spectrum is presented, showing that the methodology employed in this study is suitable

Perception of Life as Stressful, Not Biological Response to Stress, Is Associated with Greater Social Disability in Adults with Autism Spectrum Disorder

Science.gov (United States)

Bishop-Fitzpatrick, Lauren; Minshew, Nancy J.; Mazefsky, Carla A.; Eack, Shaun M.

2017-01-01

This study examined differences between adults with autism spectrum disorder (ASD; N = 40) and typical community volunteers (N = 25) on measures of stressful life events, perceived stress, and biological stress response (cardiovascular and cortisol reactivity) during a novel social stress task. Additional analyses examined the relationship between…

Ground level cosmic ray pulse height spectrum of a 7. 5 cm diameter spherical NaI(Tl) scintillation detector for energy region below 5 MeV

Energy Technology Data Exchange (ETDEWEB)

Nagaoka, Toshi; Saito, Kimiaki; Moriuchi, Shigeru

1988-09-01

Ground level cosmic ray pulse height spectrum of a 7.5 cm diameter spherical NaI(Tl) scintillation detector was evaluated through stripping operation based on a pulse height spectrum measured on the sea and high precision response functions of the detector for U-series, Th-series and /sup 40/K. The exposure rate calculated from the determined cosmic ray pulse height spectrum was 0.21 R/h eq., which agreed well with that obtained from another method. The shape of the pulse height spectrum showed similarity to that measured at the altitude of 16,000 ft, especially in the energy region of 0 to 3 MeV. The principle of the adopted method is rather plain, however, the reliability of the spectrum is satisfactory. As the pulse height spectrum is a common information to any analytical method for environmental gamma ray using NaI(Tl) scintillation detector, it is expected to be used for simple and precise separation of cosmic ray component involved in the enviromental pulse height spectrum.

Ground level cosmic ray pulse height spectrum of a 7.5 cm diameter spherical NaI(Tl) scintillation detector for energy region below 5 MeV

International Nuclear Information System (INIS)

Nagaoka, Toshi; Saito, Kimiaki; Moriuchi, Shigeru

1988-01-01

Ground level cosmic ray pulse height spectrum of a 7.5 cm diameter spherical NaI(Tl) scintillation detector was evaluated through stripping operation based on a pulse height spectrum measured on the sea and high precision response functions of the detector for U-series, Th-series and 40 K. The exposure rate calculated from the determined cosmic ray pulse height spectrum was 0.21 μR/h eq., which agreed well with that obtained from another method. The shape of the pulse height spectrum showed similarity to that measured at the altitude of 16,000 ft, especially in the energy region of 0 to 3 MeV. The principle of the adopted method is rather plain, however, the reliability of the spectrum is satisfactory. As the pulse height spectrum is a common information to any analytical method for environmental gamma ray using NaI(Tl) scintillation detector, it is expected to be used for simple and precise separation of cosmic ray component involved in the enviromental pulse height spectrum. (author)

A Synchronisation Method For Informed Spread-Spectrum Audiowatermarking

OpenAIRE

Pierre-Yves Fulchiron; Barry O'Donovan; Guenole Silvestre; Neil Hurley

2003-01-01

Under perfect synchronisation conditions, watermarking schemes employing asymmetric spread-spectrum techniques are suitable for copy-protection of audio signals. This paper proposes to combine the use of a robust psychoacoustic projection for the extraction of a watermark feature vector along with non-linear detection functions optimised with side-information. The new proposed scheme benefits from an increased level of security through the use of asymmetric detectors. We apply this scheme to ...

Spectrum reconstruction of quasi-zero stiffness floating raft systems

International Nuclear Information System (INIS)

Li, Yingli; Xu, Daolin

2016-01-01

Chaos control can be utilized to reform the response spectra of a dynamic system, potentially useful for the acoustic reconstruction of underwater vehicles. Introduction of the quasi-zero stiffness (QZS) isolators into the chaotification system can greatly reduce the emission of vibration signals from vehicles. In this study, the QZS isolators is adopted with combination of chaotification expecting to achieve excellent performances in both vibration isolation and the camouflage of vibration signal features. A nonlinear time delay control scheme is proposed to chaotify the QZS system in order to reconstruct the output spectrum features of the acoustic noise induced by the machinery vibration. A high dimensional nonlinear model of the QZS system is developed to understand the spectrum characteristics of the system. From the spectrum patterns, a specific performance index is formulated to evaluate the significance of signal-noise ratio. Based on this index, the Generic Algorithm method is employed to seek the optimal control parameters which enable to eliminate the feature of line spikes emerged from broad-band spectra. The results show that the unique combination of QZS system and time delay control can effectively reform the power spectra, especially for the case with relatively high frequency.

Exploring links between genotypes, phenotypes, and clinical predictors of response to early intensive behavioural intervention in Autism Spectrum Disorder

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Valsamma eEapen

2013-09-01

Full Text Available Autism Spectrum Disorder (ASD is amongst the most familial of psychiatric disorders. Twin and family studies have demonstrated a monozygotic concordance rate of 70–90%, dizygotic concordance of around 10% and more than a 20-fold increase in risk for first-degree relatives. Despite major advances in the genetics of autism, the relationship between different aspects of the behavioural and cognitive phenotype and their underlying genetic liability is still unclear. This is complicated by the heterogeneity of autism, which exists at both genetic and phenotypic levels. Given this heterogeneity, one method to find homogeneous entities and link these with specific genotypes would be to pursue endophenotypes. Evidence from neuroimaging, eye tracking and electrophysiology studies supports the hypothesis that, building on genetic vulnerability, ASD emerges from a developmental cascade in which a deficit in attention to social stimuli leads to impaired interactions with primary caregivers. This results in abnormal development of the neurocircuitry responsible for social cognition, which in turn adversely affects later behavioural and functional domains dependent on these early processes, such as language development. Such a model begets a heterogeneous clinical phenotype, and is also supported by studies demonstrating better clinical outcomes with earlier treatment. Treatment response following intensive early behavioural intervention in ASD is also distinctly variable; however, relatively little is known about specific elements of the clinical phenotype that may predict response to current behavioural treatments. This paper overviews the literature regarding genotypes, phenotypes and predictors of response to behavioural intervention in ASD and presents suggestions for future research to explore linkages between these that would enable better identification of, and increased treatment efficacy for, ASD.

Generate floor response spectra, Part 2: Response spectra for equipment-structure resonance

International Nuclear Information System (INIS)

Li, Bo; Jiang, Wei; Xie, Wei-Chau; Pandey, Mahesh D.

2015-01-01

Highlights: • The concept of tRS is proposed to deal with tuning of equipment and structures. • Established statistical approaches for estimating tRS corresponding to given GRS. • Derived a new modal combination rule from the theory of random vibration. • Developed efficient and accurate direct method for generating floor response spectra. - Abstract: When generating floor response spectra (FRS) using the direct spectra-to-spectra method developed in the companion paper, probability distribution of t-response spectrum (tRS), which deals with equipment-structure resonance or tuning, corresponding to a specified ground response spectrum (GRS) is required. In this paper, simulation results using a large number of horizontal and vertical ground motions are employed to establish statistical relationships between tRS and GRS. It is observed that the influence of site conditions on horizontal statistical relationships is negligible, whereas the effect of site conditions on vertical statistical relationships cannot be ignored. Considering the influence of site conditions, horizontal statistical relationship suitable for all site conditions and vertical statistical relationships suitable for hard sites and soft sites, respectively, are established. The horizontal and vertical statistical relationships are suitable to estimate tRS for design spectra in USNRC R.G. 1.60 and NUREG/CR-0098, Uniform Hazard Spectra (UHS) in Western North America (WNA), or any GRS falling inside the valid coverage of the statistical relationship. For UHS with significant high frequency spectral accelerations, such as UHS in Central and Eastern North America (CENA), an amplification ratio method is proposed to estimate tRS. Numerical examples demonstrate that the statistical relationships and the amplification ratio method are acceptable to estimate tRS for given GRS and to generate FRS using the direct method in different practical situations.

Generate floor response spectra, Part 2: Response spectra for equipment-structure resonance

Energy Technology Data Exchange (ETDEWEB)

Li, Bo, E-mail: b68li@uwaterloo.ca; Jiang, Wei, E-mail: w46jiang@uwaterloo.ca; Xie, Wei-Chau, E-mail: xie@uwaterloo.ca; Pandey, Mahesh D., E-mail: mdpandey@uwaterloo.ca

2015-11-15

Highlights: • The concept of tRS is proposed to deal with tuning of equipment and structures. • Established statistical approaches for estimating tRS corresponding to given GRS. • Derived a new modal combination rule from the theory of random vibration. • Developed efficient and accurate direct method for generating floor response spectra. - Abstract: When generating floor response spectra (FRS) using the direct spectra-to-spectra method developed in the companion paper, probability distribution of t-response spectrum (tRS), which deals with equipment-structure resonance or tuning, corresponding to a specified ground response spectrum (GRS) is required. In this paper, simulation results using a large number of horizontal and vertical ground motions are employed to establish statistical relationships between tRS and GRS. It is observed that the influence of site conditions on horizontal statistical relationships is negligible, whereas the effect of site conditions on vertical statistical relationships cannot be ignored. Considering the influence of site conditions, horizontal statistical relationship suitable for all site conditions and vertical statistical relationships suitable for hard sites and soft sites, respectively, are established. The horizontal and vertical statistical relationships are suitable to estimate tRS for design spectra in USNRC R.G. 1.60 and NUREG/CR-0098, Uniform Hazard Spectra (UHS) in Western North America (WNA), or any GRS falling inside the valid coverage of the statistical relationship. For UHS with significant high frequency spectral accelerations, such as UHS in Central and Eastern North America (CENA), an amplification ratio method is proposed to estimate tRS. Numerical examples demonstrate that the statistical relationships and the amplification ratio method are acceptable to estimate tRS for given GRS and to generate FRS using the direct method in different practical situations.

Neutron spectrum unfolding using genetic algorithm in a Monte Carlo simulation

Energy Technology Data Exchange (ETDEWEB)

Suman, Vitisha [Health Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Sarkar, P.K., E-mail: pksarkar02@gmail.com [Manipal Centre for Natural Sciences, Manipal University, Manipal 576104 (India)

2014-02-11

A spectrum unfolding technique GAMCD (Genetic Algorithm and Monte Carlo based spectrum Deconvolution) has been developed using the genetic algorithm methodology within the framework of Monte Carlo simulations. Each Monte Carlo history starts with initial solution vectors (population) as randomly generated points in the hyper dimensional solution space that are related to the measured data by the response matrix of the detection system. The transition of the solution points in the solution space from one generation to another are governed by the genetic algorithm methodology using the techniques of cross-over (mating) and mutation in a probabilistic manner adding new solution points to the population. The population size is kept constant by discarding solutions having lesser fitness values (larger differences between measured and calculated results). Solutions having the highest fitness value at the end of each Monte Carlo history are averaged over all histories to obtain the final spectral solution. The present method shows promising results in neutron spectrum unfolding for both under-determined and over-determined problems with simulated test data as well as measured data when compared with some existing unfolding codes. An attractive advantage of the present method is the independence of the final spectra from the initial guess spectra.

Neutron spectrum unfolding using genetic algorithm in a Monte Carlo simulation

International Nuclear Information System (INIS)

Suman, Vitisha; Sarkar, P.K.

2014-01-01

A spectrum unfolding technique GAMCD (Genetic Algorithm and Monte Carlo based spectrum Deconvolution) has been developed using the genetic algorithm methodology within the framework of Monte Carlo simulations. Each Monte Carlo history starts with initial solution vectors (population) as randomly generated points in the hyper dimensional solution space that are related to the measured data by the response matrix of the detection system. The transition of the solution points in the solution space from one generation to another are governed by the genetic algorithm methodology using the techniques of cross-over (mating) and mutation in a probabilistic manner adding new solution points to the population. The population size is kept constant by discarding solutions having lesser fitness values (larger differences between measured and calculated results). Solutions having the highest fitness value at the end of each Monte Carlo history are averaged over all histories to obtain the final spectral solution. The present method shows promising results in neutron spectrum unfolding for both under-determined and over-determined problems with simulated test data as well as measured data when compared with some existing unfolding codes. An attractive advantage of the present method is the independence of the final spectra from the initial guess spectra

Spectrum-to-Spectrum Searching Using a Proteome-wide Spectral Library*

Science.gov (United States)

Yen, Chia-Yu; Houel, Stephane; Ahn, Natalie G.; Old, William M.

2011-01-01

The unambiguous assignment of tandem mass spectra (MS/MS) to peptide sequences remains a key unsolved problem in proteomics. Spectral library search strategies have emerged as a promising alternative for peptide identification, in which MS/MS spectra are directly compared against a reference library of confidently assigned spectra. Two problems relate to library size. First, reference spectral libraries are limited to rediscovery of previously identified peptides and are not applicable to new peptides, because of their incomplete coverage of the human proteome. Second, problems arise when searching a spectral library the size of the entire human proteome. We observed that traditional dot product scoring methods do not scale well with spectral library size, showing reduction in sensitivity when library size is increased. We show that this problem can be addressed by optimizing scoring metrics for spectrum-to-spectrum searches with large spectral libraries. MS/MS spectra for the 1.3 million predicted tryptic peptides in the human proteome are simulated using a kinetic fragmentation model (MassAnalyzer version2.1) to create a proteome-wide simulated spectral library. Searches of the simulated library increase MS/MS assignments by 24% compared with Mascot, when using probabilistic and rank based scoring methods. The proteome-wide coverage of the simulated library leads to 11% increase in unique peptide assignments, compared with parallel searches of a reference spectral library. Further improvement is attained when reference spectra and simulated spectra are combined into a hybrid spectral library, yielding 52% increased MS/MS assignments compared with Mascot searches. Our study demonstrates the advantages of using probabilistic and rank based scores to improve performance of spectrum-to-spectrum search strategies. PMID:21532008

Sustainability as Social Contract: Textile and Apparel Professionals’ Value Conflicts within the Corporate Moral Responsibility Spectrum

Directory of Open Access Journals (Sweden)

Rachel LoMonaco-Benzing

2016-12-01

Full Text Available Current discussions of sustainability in the textile and apparel (T&A supply chain tend to focus on consumer behavior or methods of production. Few studies investigate how T&A supply chain members experience corporate sustainability initiatives within their own moral value spectrum. This study was designed to describe the gaps that might exist between personal and corporate moral values of T&A supply chain members, and how individuals manage such gaps to align personal and corporate identities. The researchers investigated the views of ten T&A supply chain members residing in the United States, both as employees and consumers of T&A companies, through semi-structured interviews. Dunfee’s extant social contracts and Schwartz’s theory of basic values were used as theoretical frameworks to better understand the participants’ lived experiences in negotiating personal and corporate expectations. The findings revealed three themes: (a nature of the value gap; (b frustration due to the value gap; and (c strategies to manage the value gap. The strategies used to realign values split into either those that held sustainability as their responsibility and worked to move corporate values toward their personal values; or those that shifted the blame to others so that their values could remain untouched.

COMPENSATION OF THE IONOSPHERIC EFFECTS ON SAR INTERFEROGRAM BASED ON RANGE SPLIT-SPECTRUM AND AZIMUTH OFFSET METHODS – A CASE STUDY OF YUSHU EARTHQUAKE

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Y. F. He

2018-04-01

Full Text Available InSAR technique can measure the surface deformation with the accuracy of centimeter-level or even millimeter and therefore has been widely used in the deformation monitoring associated with earthquakes, volcanoes, and other geologic process. However, ionospheric irregularities can lead to the wavy fringes in the low frequency SAR interferograms, which disturb the actual information of geophysical processes and thus put severe limitations on ground deformations measurements. In this paper, an application of two common methods, the range split-spectrum and azimuth offset methods are exploited to estimate the contributions of the ionosphere, with the aim to correct ionospheric effects in interferograms. Based on the theoretical analysis and experiment, a performance analysis is conducted to evaluate the efficiency of these two methods. The result indicates that both methods can mitigate the ionospheric effect in SAR interferograms and the range split-spectrum method is more precise than the other one. However, it is also found that the range split-spectrum is easily contaminated by the noise, and the achievable accuracy of the azimuth offset method is limited by the ambiguous integral constant, especially with the strong azimuth variations induced by the ionosphere disturbance.

The energy spectrum of 662 keV photons in a water equivalent phantom

International Nuclear Information System (INIS)

Akar Tarim, U.; Gurler, O.; Ozmutlu, E.N.; Yalcin, S.; Gundogdu, O.; Sharaf, J.M.; Bradley, D.A.

2012-01-01

Investigation is made on the energy spectrum of photons originating from interactions of 662 keV primary gamma-ray photons emitted by a point source positioned at the centre of a water equivalent solid phantom of dimensions 19 cm×19 cm×24 cm. Peaks resulting from total energy loss (photopeak) and multiple and back scattering have been observed using a 51 mm×51 mm NaI(Tl) detector; good agreement being found between the measured and simulated response functions. The energy spectrum of the gamma photons obtained through the Monte Carlo simulation reveals local maxima at about 100 keV and 210 keV, being also observed in the experimental response function. Such spectra can be used as a method of testing the water equivalence of solid phantom media before their use for dosimetry measurements. - Highlights: ► Peaks resulting from total energy loss (photopeak) and multiple and back scattering were observed. ► Energy distribution of γ-ray photons from a point source at the centre of a water equivalent solid phantom. ► The method can be applied to various detector geometries.

An adaptive quantum mechanics/molecular mechanics method for the infrared spectrum of water: incorporation of the quantum effect between solute and solvent.

Science.gov (United States)

Watanabe, Hiroshi C; Banno, Misa; Sakurai, Minoru

2016-03-14

Quantum effects in solute-solvent interactions, such as the many-body effect and the dipole-induced dipole, are known to be critical factors influencing the infrared spectra of species in the liquid phase. For accurate spectrum evaluation, the surrounding solvent molecules, in addition to the solute of interest, should be treated using a quantum mechanical method. However, conventional quantum mechanics/molecular mechanics (QM/MM) methods cannot handle free QM solvent molecules during molecular dynamics (MD) simulation because of the diffusion problem. To deal with this problem, we have previously proposed an adaptive QM/MM "size-consistent multipartitioning (SCMP) method". In the present study, as the first application of the SCMP method, we demonstrate the reproduction of the infrared spectrum of liquid-phase water, and evaluate the quantum effect in comparison with conventional QM/MM simulations.

Does obsessive-compulsive personality disorder belong within the obsessive-compulsive spectrum?

Science.gov (United States)

Fineberg, Naomi A; Sharma, Punita; Sivakumaran, Thanusha; Sahakian, Barbara; Chamberlain, Sam R; Chamberlain, Sam

2007-06-01

It has been proposed that certain Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Axis I disorders share overlapping clinical features, genetic contributions, and treatment response and fall within an "obsessive-compulsive" spectrum. Obsessive-compulsive personality disorder (OCPD) resembles obsessive-compulsive disorder (OCD) and other spectrum disorders in terms of phenomenology, comorbidity, neurocognition, and treatment response. This article critically examines the nosological profile of OCPD with special reference to OCD and related disorders. By viewing OCPD as a candidate member of the obsessive-compulsive spectrum, we gain a fresh approach to understanding its neurobiology, etiology, and potential treatments.

Clinical heterogeneity among people with high functioning autism spectrum conditions: evidence favouring a continuous severity gradient

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Woodbury-Smith Marc

2008-02-01

Full Text Available Abstract Background Autism Spectrum Conditions (ASCs are characterized by a high degree of clinical heterogeneity, but the extent to which this variation represents a severity gradient versus discrete phenotypes is unclear. This issue has complicated genetic studies seeking to investigate the genetic basis of the high hereditability observed clinically in those with an ASC. The aim of this study was to examine the possible clustering of symptoms associated with ASCs to determine whether the observed distribution of symptom type and severity supported either a severity or a symptom subgroup model to account for the phenotypic variation observed within the ASCs. Methods We investigated the responses of a group of adults with higher functioning ASCs on the fifty clinical features examined in the Autism Spectrum Quotient, a screening questionnaire used in the diagnosis of higher functioning ASCs. In contrast to previous studies we have used this instrument with no a priori assumptions about any underlying factor structure of constituent items. The responses obtained were analyzed using complete linkage hierarchical cluster analysis. For the members of each cluster identified the mean score on each Autism Spectrum Quotient question was calculated. Results Autism Spectrum Quotient responses from a total of 333 individuals between the ages of 16.6 and 78.0 years were entered into the hierarchical cluster analysis. The four cluster solution was the one that generated the largest number of clusters that did not also include very small cluster sizes, defined as a membership comprising 10 individuals or fewer. Examination of these clusters demonstrated that they varied in total Autism Spectrum Quotient but that the profiles across the symptoms comprising the Autism Spectrum Quotient did not differ independently of this severity factor. Conclusion These results are consistent with a unitary spectrum model, suggesting that the clinical heterogeneity observed

The Effect of Pivotal Response Treatment in Children with Autism Spectrum Disorders: A Non-Randomized Study with a Blinded Outcome Measure

Science.gov (United States)

Duifhuis, E. A.; den Boer, J. C.; Doornbos, A.; Buitelaar, J. K.; Oosterling, I. J.; Klip, H.

2017-01-01

Purpose of this quasi-experimental trial was to investigate the effect of Pivotal response treatment (PRT) versus treatment as usual (TAU) on autism symptoms. Children with autism spectrum disorder (ASD), aged 3-8 years, received either PRT (n = 11) or TAU (n = 13). Primary outcome measure was the total score on the Autism Diagnostic Observation…

Joint attention responses of children with autism spectrum disorder to simple versus complex music.

Science.gov (United States)

Kalas, Amy

2012-01-01

Joint attention deficits are viewed as one of the earliest manifestations and most characteristic features of the social deficits in Autism Spectrum Disorder (ASD). The purpose of this study was to examine the effect of simple versus complex music on joint attention of children with ASD. Thirty children with a diagnosis of ASD participated in this study. Fifteen of the participants were diagnosed with severe ASD and 15 were diagnosed with mild/moderate ASD. Each participant took part in six, 10-minute individual music conditions (3 simple & 3 complex) over a 3-week period. Each condition was designed to elicit responses to joint attention. RESULTS indicated a statistically significant interaction between music modality and functioning level. Therefore, the effect of simple versus complex music was dependent on functioning level. Specifically, the Simple Music Condition was more effective in eliciting Responses to Joint Attention (RJA) for children diagnosed with severe ASD, whereas the Complex Music Condition was more effective in eliciting RJA for children diagnosed with mild/moderate ASD. The results of the present study indicate that for children in the severe range of functioning, music that is simple, with clear and predictable pattems, may be most effective in eliciting responses to bids for joint attention. On the contrary, for children in the mild/moderate range of functioning, music that is more complex and variable may be most effective in eliciting responses to bids for joint attention. These results demonstrate that careful manipulation of specific musical elements can help provide the optimal conditions for facilitating joint attention with children with ASD.

Association of Schizophrenia Spectrum and Autism Spectrum Disorder (ASD) Symptoms in Children with ASD and Clinic Controls

Science.gov (United States)

Gadow, Kenneth D.

2013-01-01

Objective: This study examines relations between the severity of specific symptoms of schizophrenia spectrum disorder (SSD) and severity of the three defining symptom domains of autism spectrum disorder (ASD) in children with ASD (N = 147) and child psychiatry outpatient referrals (Controls; N = 339). Method: Participants were subdivided into four…

Smart techniques in the dynamic spectrum alocation for cognitive wireless networks

Directory of Open Access Journals (Sweden)

Camila Salgado

2016-09-01

Full Text Available Objective: The objective of this work is to study the applications of different techniques of artificial intelligence and autonomous learning in the dynamic allocation of spectrum for cognitive wireless networks, especially the distributed ones. Method: The development of this work was done through the study and analysis of some of the most relevant publications in current literature through the search in indexed international journals in ISI and Scopus. Results: the most relevant techniques of artificial intelligence and autonomous learning were determined. Also, the ones with more applicability in the allocation of spectrum for cognitive wireless networks were determined, too. . Conclusions: The implementation of a technique, or set of them, depends on the needs in signal processing, compensation in response times, sample availability, storage capacity, learning ability and robustness, among others.

Stochastic seismic floor response analysis method for various damping systems

International Nuclear Information System (INIS)

Kitada, Y.; Hattori, K.; Ogata, M.; Kanda, J.

1991-01-01

A study using the stochastic seismic response analysis method which is applicable for the estimation of floor response spectra is carried out. It is pointed out as a shortcoming in this stochastic seismic response analysis method, that the method tends to overestimate floor response spectra for low damping systems, e.g. 1% of the critical damping ratio. An investigation on the cause of the shortcoming is carried out and a number of improvements in this method were also made to the original method by taking correlation of successive peaks in a response time history into account. The application of the improved method to a typical BWR reactor building is carried out. The resultant floor response spectra are compared with those obtained by deterministic time history analysis. Floor response spectra estimated by the improved method consistently cover the response spectra obtained by the time history analysis for various damping ratios. (orig.)

Use of technology to facilitate physical activity in children with autism spectrum disorders: A pilot study.

Science.gov (United States)

Bittner, Melissa D; Rigby, B Rhett; Silliman-French, Lisa; Nichols, David L; Dillon, Suzanna R

2017-08-01

Deficits in social behavior and communication skills are correlated with reduced gross motor skills in children with autism spectrum disorders (ASD). The ExerciseBuddy application (EB app) was designed to communicate these motor skills to those with ASD and integrates evidence-based practices such as visual support and video modeling supported by The National Professional Development Center on Autism Spectrum Disorders. The purpose of this study was to determine the effectiveness of the EB app in facilitating increased physiologic responses to physical activity via a continuous measurement of energy expenditure and heart rate versus practice-style teaching methods in children with ASD. Six children, ages 5 to 10years, diagnosed with ASD were recruited. Each participant performed a variety of locomotor or object control skills as defined by the Test of Gross Motor Development-2 once per week for 4weeks. Motor skills were communicated and demonstrated using either practice-style teaching methods or the instructional section of the EB app. Energy expenditure and heart rate were measured continuously during each 12-minute session. A Wilcoxon signed-rank test was performed to assess any differences between the use of the app and practice-style teaching methods. The use of the EB app elicited greater values for peak energy expenditure (p=0.043) and peak heart rate response (p=0.028) while performing locomotor skills but no differences were observed while performing object control skills. Similarities were observed with average physiologic responses between the use of the EB app and practice-style teaching methods. The use of the EB app may allow for a greater peak physiologic response during more dynamic movements and a similar average cardiovascular and metabolic response when compared to practice-style teaching methods in children with ASD. Published by Elsevier Inc.

Two efficient methods for measuring hydrophone frequency response in the 100 kHz to 2 MHz range

International Nuclear Information System (INIS)

Harris, G R; Maruvada, S; Gammell, P M

2004-01-01

As new medical applications of ultrasound emerge with operating frequencies in the hundreds of kilohertz to low megahertz region, it becomes more important to have convenient calibration methods for hydrophones in this frequency range. Furthermore, short diagnostic ultrasound pulses affected by finite amplitude distortion require that the hydrophone frequency response be known well below the center frequency. National standards laboratories can provide accurate calibration data at these frequencies, but the two methods now employed, laser interferometry and three-transducer reciprocity, are both single-frequency techniques, and they can be time-consuming procedures. Therefore, two efficient methods for generating a wideband acoustic pressure spectrum have been implemented to cover this frequency range. In one method a high-voltage pulse generator was used to excite a thick piezoelectric ceramic disk, producing a plane-wave acoustic pressure transient <1 μs in duration with peak amplitude of about 40 kPa. In the other technique, time delay spectrometry (TDS), a purpose-built 1-3 piezoelectric composite source transducer weakly focused at 20 cm was swept over the 0-2 MHz range. Its transmitting voltage response at 1 MHz was 11 kPa/V. The broadband pulse technique has the advantage of being simpler to implement, but TDS has a much greater signal-to-noise ratio because of the frequency-swept narrowband filter employed

A two-question method for assessing gender categories in the social and medical sciences.

Science.gov (United States)

Tate, Charlotte Chuck; Ledbetter, Jay N; Youssef, Cris P

2013-01-01

Three studies (N = 990) assessed the statistical reliability of two methods of determining gender identity that can capture transgender spectrum identities (i.e., current gender identities different from birth-assigned gender categories). Study 1 evaluated a single question with four response options (female, male, transgender, other) on university students. The missing data rate was higher than the valid response rates for transgender and other options using this method. Study 2 evaluated a method of asking two separate questions (i.e., one for current identity and another for birth-assigned category), with response options specific to each. Results showed no missing data and two times the transgender spectrum response rate compared to Study 1. Study 3 showed that the two-question method also worked in community samples, producing near-zero missing data. The two-question method also identified cisgender identities (same birth-assigned and current gender identity), making it a dynamic and desirable measurement tool for the social and medical sciences.

Detection of local inflammation induced by repeated exposure to contact allergens by use of IVIS SpectrumCT analyses

DEFF Research Database (Denmark)

Nielsen, Morten M.; Schmidt, Jonas D.; Christensen, Jan P.

2017-01-01

Background: Contact allergy is characterized by local skin inflammation that, in some cases, can result in systemic immune activation. Objectives: To investigate whether IVIS SpectrumCT analyses can be used to detect the immune response induced by contact allergens. Methods: Mice were repeatedly...... exposed to vehicle or allergens on the ears. The local and systemic responses were analysed at different times with the ProSense 750 FAST probe in IVIS SpectrumCT measurements. In addition, changes in ear thickness, cytokine profile in the skin and immunological phenotype in the draining lymph nodes...... and spleen were determined. Results: Local inflammation was detected by ProSense 750 FAST and correlated with changes in ear thickness, cytokine profile and immunological phenotype following exposure to the strong contact allergen 2,4-dinitrofluorobenzene. Analysis of the systemic response with ProSense 750...

Additional Evidence Is Needed to Recommend Acquiring a Dog to Families of Children with Autism Spectrum Disorder: A Response to Wright and Colleagues

Science.gov (United States)

Crossman, Molly K.; Kazdin, Alan E.

2016-01-01

Caregivers of children with autism spectrum disorder are vulnerable to overstated benefits of interventions, and such overstatements are common with interventions involving animals. This response to Wright, Hall, Hames, Hardmin, Mills, the Paws Team, and Mills' (2015) article, "Acquiring a Pet Dog Significantly Reduces Stress of Primary…

Spectrum 101: An Introduction to Spectrum Management

Science.gov (United States)

2004-03-01

produces a Joint Restricted Frequency List (JRFL). The JFRL consolidates and classifies the spectrum uses that are most critical to operations and to...Management Office JRFL Joint Restricted Frequency List JSC Joint Spectrum Center JSIR Joint Spectrum Interference Resolution JSME Joint Spectrum...Multifunctional Information Distribution System MILSATCOM Military Satellite Communications MOA Memorandum of Agreement MRFL Master Radio Frequency

A NRC-BNL benchmark evaluation of seismic analysis methods for non-classically damped coupled systems

International Nuclear Information System (INIS)

Xu, J.; DeGrassi, G.; Chokshi, N.

2004-01-01

Under the auspices of the U.S. Nuclear Regulatory Commission (NRC), Brookhaven National Laboratory (BNL) developed a comprehensive program to evaluate state-of-the-art methods and computer programs for seismic analysis of typical coupled nuclear power plant (NPP) systems with non-classical damping. In this program, four benchmark models of coupled building-piping/equipment systems with different damping characteristics were developed and analyzed by BNL for a suite of earthquakes. The BNL analysis was carried out by the Wilson-θ time domain integration method with the system-damping matrix computed using a synthesis formulation as presented in a companion paper [Nucl. Eng. Des. (2002)]. These benchmark problems were subsequently distributed to and analyzed by program participants applying their uniquely developed methods and computer programs. This paper is intended to offer a glimpse at the program, and provide a summary of major findings and principle conclusions with some representative results. The participant's analysis results established using complex modal time history methods showed good comparison with the BNL solutions, while the analyses produced with either complex-mode response spectrum methods or classical normal-mode response spectrum method, in general, produced more conservative results, when averaged over a suite of earthquakes. However, when coupling due to damping is significant, complex-mode response spectrum methods performed better than the classical normal-mode response spectrum method. Furthermore, as part of the program objectives, a parametric assessment is also presented in this paper, aimed at evaluation of the applicability of various analysis methods to problems with different dynamic characteristics unique to coupled NPP systems. It is believed that the findings and insights learned from this program will be useful in developing new acceptance criteria and providing guidance for future regulatory activities involving license

Examination of Studies Targeting Social Skills with Pivotal Response Treatment

Science.gov (United States)

Bozkus Genc, Gulden; Vuran, Sezgin

2013-01-01

In early education, especially in effective teaching to children with autism spectrum disorders, the teaching methods which are applicable in natural settings like pivotal response treatment (PRT) are commonly used. It is one of the naturalistic intervention models aiming to facilitate the stimulant-response generalization, decrease the dependency…

A multigroup analysis from a continuos energy spectrum approach by a MC method

International Nuclear Information System (INIS)

Camargo, Dayana Q. de; Bodmann, Bardo E.J.; Vilhena, Marco T. de

2009-01-01

In this work, the Monte Carlo method is applied to the energy dependent three- dimensional neutron transport equation, in order to analyze the change in the spectrum energy depending on the Monte Carlo step. The present work is a first step into a new direction where spectral influence on criticality may be analyzed. The method is based on the monitoring of a large number of individual realizations of neutron histories (i.e. microscopic interaction sequence) where the average behavior of neutrons yields an approximate solution for the neutron transport equation. The Monte Carlo is implemented using continuous functions, with respect to energy, for the cross sections of materials, functions which are obtained by parametrizations of the cross sections. The type of interaction that the neutron will suffer and the characteristics of their displacement in the element are estimated randomly following the relevant probability distributions. (author)

[Continuum based fast Fourier transform processing of infrared spectrum].

Science.gov (United States)

Liu, Qing-Jie; Lin, Qi-Zhong; Wang, Qin-Jun; Li, Hui; Li, Shuai

2009-12-01

To recognize ground objects with infrared spectrum, high frequency noise removing is one of the most important phases in spectrum feature analysis and extraction. A new method for infrared spectrum preprocessing was given combining spectrum continuum processing and Fast Fourier Transform (CFFT). Continuum was firstly removed from the noise polluted infrared spectrum to standardize hyper-spectra. Then the spectrum was transformed into frequency domain (FD) with fast Fourier transform (FFT), separating noise information from target information After noise eliminating from useful information with a low-pass filter, the filtered FD spectrum was transformed into time domain (TD) with fast Fourier inverse transform. Finally the continuum was recovered to the spectrum, and the filtered infrared spectrum was achieved. Experiment was performed for chlorite spectrum in USGS polluted with two kinds of simulated white noise to validate the filtering ability of CFFT by contrast with cubic function of five point (CFFP) in time domain and traditional FFT in frequency domain. A circle of CFFP has limited filtering effect, so it should work much with more circles and consume more time to achieve better filtering result. As for conventional FFT, Gibbs phenomenon has great effect on preprocessing result at edge bands because of special character of rock or mineral spectra, while works well at middle bands. Mean squared error of CFFT is 0. 000 012 336 with cut-off frequency of 150, while that of FFT and CFFP is 0. 000 061 074 with cut-off frequency of 150 and 0.000 022 963 with 150 working circles respectively. Besides the filtering result of CFFT can be improved by adjusting the filter cut-off frequency, and has little effect on working time. The CFFT method overcomes the Gibbs problem of FFT in spectrum filtering, and can be more convenient, dependable, and effective than traditional TD filter methods.

Novel Cooperative Spectrum Sensing Methods And Their Limitations

DEFF Research Database (Denmark)

Kiilerich Pratas, Nuno

2012-01-01

$-calculus, denoted as Bounded Broadcast Calculus. This analysis is done over centralized, decentralized and relay aided topologies. The outcome of this analysis is a theorem where it is stated, which properties a protocol should have so that it can be deemed correct, i.e. that it performs as intended, over each...... source. The node selection scheme is proposed in a centralized and in a decentralized version. These versions can complement each other and therefore lead to a more robust cooperative spectrum sensing mechanism....

Spread spectrum image steganography.

Science.gov (United States)

Marvel, L M; Boncelet, C R; Retter, C T

1999-01-01

In this paper, we present a new method of digital steganography, entitled spread spectrum image steganography (SSIS). Steganography, which means "covered writing" in Greek, is the science of communicating in a hidden manner. Following a discussion of steganographic communication theory and review of existing techniques, the new method, SSIS, is introduced. This system hides and recovers a message of substantial length within digital imagery while maintaining the original image size and dynamic range. The hidden message can be recovered using appropriate keys without any knowledge of the original image. Image restoration, error-control coding, and techniques similar to spread spectrum are described, and the performance of the system is illustrated. A message embedded by this method can be in the form of text, imagery, or any other digital signal. Applications for such a data-hiding scheme include in-band captioning, covert communication, image tamperproofing, authentication, embedded control, and revision tracking.

High Behavioral Approach System (BAS) sensitivity, reward responsiveness, and goal-striving predict first onset of bipolar spectrum disorders: a prospective behavioral high-risk design.

Science.gov (United States)

Alloy, Lauren B; Bender, Rachel E; Whitehouse, Wayne G; Wagner, Clara A; Liu, Richard T; Grant, David A; Jager-Hyman, Shari; Molz, Ashleigh; Choi, James Y; Harmon-Jones, Eddie; Abramson, Lyn Y

2012-05-01

A prospective, behavioral high-risk design provided a theoretically guided examination of vulnerability to first onset of bipolar spectrum disorder based on the Behavioral Approach System (BAS) model. Adolescents (ages 14-19) at an "age of risk" for bipolar disorder onset were screened on BAS sensitivity by interviewers blind to current symptoms, lifetime history, and family history of psychopathology. Participants were selected with high versus moderate levels of BAS sensitivity and administered a lifetime diagnostic interview. Those with a bipolar spectrum disorder, psychosis, or hypomanic episode with onset prior to the BAS sensitivity assessment were excluded. High BAS (n = 171) and moderate BAS (n = 119) sensitivity participants in the final sample completed baseline measures of symptoms, goal-setting, and reward responsiveness and were followed prospectively with semistructured diagnostic interviews every 6 months. Consistent with the vulnerability hypothesis of the BAS model of bipolar disorder, high BAS participants had a greater likelihood, and shorter time to onset, of bipolar spectrum disorder than moderate BAS participants across an average of 12.8 months of follow-up (12.9% vs. 4.2%), controlling for baseline depressive and hypomanic symptoms, and family history of bipolar disorder. High reward responsiveness on a behavioral task and ambitious goal-striving for popular fame and financial success (but not impulsivity) also predicted first onset of bipolar spectrum disorder controlling for the covariates and BAS risk group, and ambitious goal-striving partially mediated the BAS risk group effect. We discuss implications of the findings for the BAS model of bipolar disorder and early intervention efforts.

Development of methodology and computer programs for the ground response spectrum and the probabilistic seismic hazard analysis

Energy Technology Data Exchange (ETDEWEB)

Kim, Joon Kyoung [Semyung Univ., Research Institute of Industrial Science and Technol , Jecheon (Korea, Republic of)

1996-12-15

Objective of this study is to investigate and develop the methodologies and corresponding computer codes, compatible to the domestic seismological and geological environments, for estimating ground response spectrum and probabilistic seismic hazard. Using the PSHA computer program, the Cumulative Probability Functions(CPDF) and Probability Functions (PDF) of the annual exceedence have been investigated for the analysis of the uncertainty space of the annual probability at ten interested seismic hazard levels (0.1 g to 0.99 g). The cumulative provability functions and provability functions of the annual exceedence have been also compared to those results from the different input parameter spaces.

Different brain responses during empathy in autism spectrum disorders versus conduct disorder and callous-unemotional traits.

Science.gov (United States)

Klapwijk, Eduard T; Aghajani, Moji; Colins, Olivier F; Marijnissen, Godfried M; Popma, Arne; van Lang, Natasja D J; van der Wee, Nic J A; Vermeiren, Robert R J M

2016-06-01

Deficits in empathy are reported in autism spectrum disorders (ASD) and also underlie antisocial behavior of individuals with conduct disorder and callous-unemotional traits (CD/CU+). Many studies suggest that individuals with ASD are typically impaired in cognitive aspects of empathy, and individuals with CD/CU+ typically in affective aspects. In the current study, we compared the neural correlates of cognitive and affective aspects of empathy between youth with ASD and youth with CD/CU+. Functional magnetic resonance imaging (fMRI) was used to assess boys with ASD (N = 23), boys with CD/CU+ (N = 23), and typically developing (TD) boys (N = 33), aged 15-19 years. Angry and fearful faces were presented and participants were asked to either infer the emotional state from the face (other-task; emotion recognition) or to judge their own emotional response to the face (self-task; emotional resonance). During emotion recognition, boys with ASD showed reduced responses compared to the other groups in the ventromedial prefrontal cortex (vmPFC). During emotional resonance, the CD/CU+ and ASD groups showed reduced amygdala responses compared to the TD controls, boys with ASD showed reduced responses in bilateral hippocampus, and the CD/CU+ boys showed reduced responses in the inferior frontal gyrus (IFG) and anterior insula (AI). Results suggest differential abnormal brain responses associated with specific aspects of empathic functioning in ASD and CD/CU+. Decreased amygdala responses in ASD and CD/CU+ might point to impaired emotion processing in both disorders, whereas reduced vmPFC responses suggest problems in processing cognitive aspects of empathy in ASD. Reduced IFG/AI responses, finally, suggest decreased emotional resonance in CD/CU+. © 2015 Association for Child and Adolescent Mental Health.

Cognitive Spectrum Efficient Multiple Access Technique using Relay Systems

DEFF Research Database (Denmark)

Frederiksen, Flemming Bjerge; Prasad, Ramjee

2007-01-01

Methods to enhance the use of the frequency spectrum by automatical spectrum sensing plus spectrum sharing in a cognitive radio technology context will be presented and discussed in this paper. Ideas to increase the coverage of cellular systems by relay channels, relay stations and collaborate...

The Diffraction Response Interpolation Method

DEFF Research Database (Denmark)

Jespersen, Søren Kragh; Wilhjelm, Jens Erik; Pedersen, Peder C.

1998-01-01

Computer modeling of the output voltage in a pulse-echo system is computationally very demanding, particularly whenconsidering reflector surfaces of arbitrary geometry. A new, efficient computational tool, the diffraction response interpolationmethod (DRIM), for modeling of reflectors in a fluid...... medium, is presented. The DRIM is based on the velocity potential impulseresponse method, adapted to pulse-echo applications by the use of acoustical reciprocity. Specifically, the DRIM operates bydividing the reflector surface into planar elements, finding the diffraction response at the corners...

A comparison of methods for teaching receptive labeling to children with autism spectrum disorders: a systematic replication.

Science.gov (United States)

Grow, Laura L; Kodak, Tiffany; Carr, James E

2014-01-01

Previous research has demonstrated that the conditional-only method (starting with a multiple-stimulus array) is more efficient than the simple-conditional method (progressive incorporation of more stimuli into the array) for teaching receptive labeling to children with autism spectrum disorders (Grow, Carr, Kodak, Jostad, & Kisamore,). The current study systematically replicated the earlier study by comparing the 2 approaches using progressive prompting with 2 boys with autism. The results showed that the conditional-only method was a more efficient and reliable teaching procedure than the simple-conditional method. The results further call into question the practice of teaching simple discriminations to facilitate acquisition of conditional discriminations. © Society for the Experimental Analysis of Behavior.

Comparison of detection methods for extended-spectrum beta-lactamases in Escherichia coli strains

Directory of Open Access Journals (Sweden)

Ewelina Kałużna

2014-06-01

Full Text Available Introduction: Detection of extended-spectrum beta-lactamases (ESBLs could be a major challenge for microbiologists – the difficulties arise mainly from the phenotypic differences among strains.Materials and Methods: Evaluation of ESBLs was performed on 42 strains of E. coli by: 1 DDST on MHA, 2 DDST on MHA with cloxacillin, 3 CT on MHA, according to CLSI, 4 CT on MHA with cloxacillin, 5 Etest ESBL (AB Biodisk, 6 CHROMagarTM ESBL (GRASO, 7 ChromID® ESBL (bioMérieux, and 8 automatic system VITEK2 ESBL test (bioMérieux.Result: Positive results were obtained for 20 strains using method 1, for 18 strains using method 2, 17 by method 3, 14 by method 4, 11 by method 5, 39 by method 6, 40 by method 7, and 15 by method 8. Using Etest ESBL 6.0 non-determinable results were obtained. The most consistent results were obtained when comparing the results of method 3 with results of method 2 (97.6%, and comparing the results obtained using methods 3 and 8 (95.2%.Conclusions: Based on our study we conclude that the chromogenic media can only be used as a screening method for the detection of ESBLs in E. coli rods. Etest is less useful compared to other phenotype methods, due to the impossibility of obtaining results for all the tested strains. Adding cloxacillin to MHA does not increase the frequency of detection of ESBLs in E. coli strains. DDST seems to be the most reliable among phenotypic methods for the detection of ESBLs in E. coli rods.

An Expansion Method to Unfold Proton Recoil Spectra

Energy Technology Data Exchange (ETDEWEB)

Kockum, J

1970-07-01

A method is given to obtain a good estimate of the input neutron spectrum from a pulse-height distribution measured with proportional counters filled with a hydrogenous gas. The method consists of expanding the sought estimate as a product of two functions where one is obtained by differentiating the pulse-height distribution and the other is a power series of the neutron energy. The coefficients of this series are determined by a least-squares fit of the calculated pulse-height distribution to the measured one. The method has been tested on pulse-height distributions obtained by calculations from a realistic neutron spectrum and response functions for a spherical counter 3. 94 cm in diameter and filled with 7 atm. of methane and 1 atm. of hydrogen, respectively. In the former case it is possible with the method described, to unfold pulse-height distributions up to a neutron energy of about 3 MeV to within 10 % of the input spectrum. The differentiating procedure included in the method ensures that all spectral details not smoothed out by the finite resolution of the counter, are kept in the spectrum estimate. A realistic estimate of the statistical uncertainty of each neutron spectrum value is given. Some of the possible systematical errors caused by uncertainties in input data have been investigated.

Spectrum

DEFF Research Database (Denmark)

Høgfeldt Hansen, Leif

2016-01-01

The publication functions as a proces description of the development and construction of an urban furniture SPECTRUM in the city of Gwangju, Republic of Korea. It is used as the cataloque for the exhibition of Spectrum.......The publication functions as a proces description of the development and construction of an urban furniture SPECTRUM in the city of Gwangju, Republic of Korea. It is used as the cataloque for the exhibition of Spectrum....

A new method of testing space-based high-energy electron detectors with radioactive electron sources

Science.gov (United States)

Zhang, S. Y.; Shen, G. H.; Sun, Y.; Zhou, D. Z.; Zhang, X. X.; Li, J. W.; Huang, C.; Zhang, X. G.; Dong, Y. J.; Zhang, W. J.; Zhang, B. Q.; Shi, C. Y.

2016-05-01

Space-based electron detectors are commonly tested using radioactive β-sources which emit a continuous spectrum without spectral lines. Therefore, the tests are often to be considered only qualitative. This paper introduces a method, which results in more than a qualitative test even when using a β-source. The basic idea is to use the simulated response function of the instrument to invert the measured spectrum and compare this inverted spectrum with a reference spectrum obtained from the same source. Here we have used Geant4 to simulate the instrument response function (IRF) and a 3.5 mm thick Li-drifted Si detector to obtain the reference 90Sr/90Yi source spectrum to test and verify the geometric factors of the Omni-Direction Particle Detector (ODPD) on the Tiangong-1 (TG-1) and Tiangong-2 (TG-2) spacecraft. The TG spacecraft are experimental space laboratories and prototypes of the Chinese space station. The excellent agreement between the measured and reference spectra demonstrates that this test method can be used to quantitatively assess the quality of the instrument. Due to its simplicity, the method is faster and therefore more efficient than traditional full calibrations using an electron accelerator.

Neural mechanisms of negative reinforcement in children and adolescents with autism spectrum disorders

OpenAIRE

Damiano, Cara R; Cockrell, Dillon C; Dunlap, Kaitlyn; Hanna, Eleanor K; Miller, Stephanie; Bizzell, Joshua; Kovac, Megan; Turner-Brown, Lauren; Sideris, John; Kinard, Jessica; Dichter, Gabriel S

2015-01-01

Background Previous research has found accumulating evidence for atypical reward processing in autism spectrum disorders (ASD), particularly in the context of social rewards. Yet, this line of research has focused largely on positive social reinforcement, while little is known about the processing of negative reinforcement in individuals with ASD. Methods The present study examined neural responses to social negative reinforcement (a face displaying negative affect) and non-social negative re...

Fingerprint extraction from interference destruction terahertz spectrum.

Science.gov (United States)

Xiong, Wei; Shen, Jingling

2010-10-11

In this paper, periodic peaks in a terahertz absorption spectrum are confirmed to be induced from interference effects. Theoretically, we explained the periodic peaks and calculated the locations of them. Accordingly, a technique was suggested, with which the interference peaks in a terahertz spectrum can be eliminated and therefore a real terahertz absorption spectrum can be obtained. Experimentally, a sample, Methamphetamine, was investigated and its terahertz fingerprint was successfully extracted from its interference destruction spectrum. This technique is useful in getting samples' terahertz fingerprint spectra, and furthermore provides a fast nondestructive testing method using a large size terahertz beam to identify materials.

An Analytical Method for Jack-Up Riser’s Fatigue Life Estimation

Directory of Open Access Journals (Sweden)

Fengde Wang

2018-01-01

Full Text Available In order to determine whether a special sea area and its sea state are available for the jack-up riser with surface blowout preventers, an analytical method is presented to estimate the jack-up riser’s wave loading fatigue life in this study. In addition, an approximate formula is derived to compute the random wave force spectrum of the small-scale structures. The results show that the response of jack-up riser is a narrow band random vibration. The infinite water depth dispersion relation between wavenumber and wave frequency can be used to calculate the wave force spectrum of small-scale structures. The riser’s response mainly consists of the additional displacement response. The fatigue life obtained by the formula proposed by Steinberg is less than that of the Bendat method.

Well logging method and apparatus using a continuous energy spectrum photon source

International Nuclear Information System (INIS)

Turcotte, R.E.

1976-01-01

In accordance with an illustrative embodiment of the present invention, a method and apparatus for logging an earth formation of interest is disclosed in which repetitive bursts of a continuous energy spectrum of photons are emitted that penetrate the media surrounding a borehole traversing the earth formation. Thereafter, indications of photons resulting from the interaction of the emitted photons and the surrounding media are obtained, each indication being obtained at a different separation from the source along the axis of the borehole. Finally, the indications are compared to determine representations of a characteristic of the media surrounding the borehole. According to one aspect of the present invention, at least one of the indications is the result of annihilation photons produced by the interaction of the emitted photons and the surrounding media

Selection of the optimum combination of responses for Wave Buoy Analogy - An approach based on local sensitivity analysis

DEFF Research Database (Denmark)

Montazeri, Najmeh; Nielsen, Ulrik Dam; Jensen, Jørgen Juncher

2016-01-01

One method to estimate the wave spectrum onboard ships is to use measured ship responses. In this method, known also as Wave Buoy Analogy, amongst various responses that are available from sensor measurements, a couple of responses (at least three) are usually utilized. Selec-tion of the best com...

Nonlinear Single Spin Spectrum Analayzer

Science.gov (United States)

Kotler, Shlomi; Akerman, Nitzan; Glickman, Yinnon; Ozeri, Roee

2014-05-01

Qubits are excellent probes of their environment. When operating in the linear regime, they can be used as linear spectrum analyzers of the noise processes surrounding them. These methods fail for strong non-Gaussian noise where the qubit response is no longer linear. Here we solve the problem of nonlinear spectral analysis, required for strongly coupled environments. Our non-perturbative analytic model shows a nonlinear signal dependence on noise power, resulting in a spectral resolution beyond the Fourier limit as well as frequency mixing. We developed a noise characterization scheme adapted to this non-linearity. We then applied it using a single trapped 88Sr+ ion as the a sensitive probe of strong, non-Gaussian, discrete magnetic field noise. With this method, we attained a ten fold improvement over the standard Fourier limit. Finally, we experimentally compared the performance of equidistant vs. Uhrig modulation schemes for spectral analysis. Phys. Rev. Lett. 110, 110503 (2013), Synopsis at http://physics.aps.org/synopsis-for/10.1103/PhysRevLett.110.110503 Current position: National Institute of Standards and Tehcnology, Boulder, CO.

A probabilistic capacity spectrum strategy for the reliability analysis of bridge pile shafts considering soil structure interaction

Directory of Open Access Journals (Sweden)

Dookie Kim

Full Text Available This paper presents a probabilistic capacity spectrum strategy for the reliability analysis of a bridge pile shaft, accounting for uncertainties in design factors in the analysis and the soil-structure interaction (SSI. Monte Carlo simulation method (MCS is adopted to determine the probabilities of failure by comparing the responses with defined limit states. The analysis considers the soil structure interaction together with the probabilistic application of the capacity spectrum method for different types of limit states. A cast-in-drilledhole (CIDH extended reinforced concrete pile shaft of a bridge is analysed using the proposed strategy. The results of the analysis show that the SSI can lead to increase or decrease of the structure's probability of failure depending on the definition of the limit states.

Sum rules in the response function method

International Nuclear Information System (INIS)

Takayanagi, Kazuo

1990-01-01

Sum rules in the response function method are studied in detail. A sum rule can be obtained theoretically by integrating the imaginary part of the response function over the excitation energy with a corresponding energy weight. Generally, the response function is calculated perturbatively in terms of the residual interaction, and the expansion can be described by diagrammatic methods. In this paper, we present a classification of the diagrams so as to clarify which diagram has what contribution to which sum rule. This will allow us to get insight into the contributions to the sum rules of all the processes expressed by Goldstone diagrams. (orig.)

Power spectrum analysis for defect screening in integrated circuit devices

Science.gov (United States)

Tangyunyong, Paiboon; Cole Jr., Edward I.; Stein, David J.

2011-12-01

A device sample is screened for defects using its power spectrum in response to a dynamic stimulus. The device sample receives a time-varying electrical signal. The power spectrum of the device sample is measured at one of the pins of the device sample. A defect in the device sample can be identified based on results of comparing the power spectrum with one or more power spectra of the device that have a known defect status.

Nonlinear response matrix methods for radiative transfer

International Nuclear Information System (INIS)

Miller, W.F. Jr.; Lewis, E.E.

1987-01-01

A nonlinear response matrix formalism is presented for the solution of time-dependent radiative transfer problems. The essential feature of the method is that within each computational cell the temperature is calculated in response to the incoming photons from all frequency groups. Thus the updating of the temperature distribution is placed within the iterative solution of the spaceangle transport problem, instead of being placed outside of it. The method is formulated for both grey and multifrequency problems and applied in slab geometry. The method is compared to the more conventional source iteration technique. 7 refs., 1 fig., 4 tabs

Development of seismic design method for piping system supported by elastoplastic damper. 3. Vibration test of three-dimensional piping model and its response analysis

International Nuclear Information System (INIS)

Namita, Yoshio; Kawahata, Jun-ichi; Ichihashi, Ichiro; Fukuda, Toshihiko.

1995-01-01

Component and piping systems in current nuclear power plants and chemical plants are designed to employ many supports to maintain safety and reliability against earthquakes. However, these supports are rigid and have a slight energy-dissipating effect. It is well known that applying high-damping supports to the piping system is very effective for reducing the seismic response. In this study, we investigated the design method of the elastoplastic damper [energy absorber (EAB)] and the seismic design method for a piping system supported by the EAB. Our final goal is to develop technology for applying the EAB to the piping system of an actual plant. In this paper, the vibration test results of the three-dimensional piping model are presented. From the test results, it is confirmed that EAB has a large energy-dissipating effect and is effective in reducing the seismic response of the piping system, and that the seismic design method for the piping system, which is the response spectrum mode superposition method using each modal damping and requires iterative calculation of EAB displacement, is applicable for the three-dimensional piping model. (author)

[Autism spectrum disorder and suicidality].

Science.gov (United States)

Huguet, G; Contejean, Y; Doyen, C

2015-09-01

Most studies on suicide exclude subjects with autism spectrum disorders, yet there is a risk group. The purpose of this article is to present the data in the literature regarding the clinical and epidemiological characteristics of suicidality in subjects with autism spectrum disorders and to identify the factors that promote the transition to action. This review was carried out using the data set collected in Medline PubMed, items with "autism spectrum disorder", "pervasive developmental disorder", "Asperger's syndrome", "suicide", "suicide attempt", and "suicide behavior". In all subjects from our research on PubMed, 21.3% of subjects with autism spectrum disorder reported suicidal ideation, have attempted suicide or died by suicide (115 out of 539 subjects) and 7.7% of subjects supported for suicidal thoughts or attempted suicide exhibited an autism spectrum disorder (62 out of 806 subjects), all ages combined. Suicidal ideation and morbid preoccupation are particularly common in adolescents and young adults. Suicide attempts are accompanied by a willingness for death and can lead to suicide. They are more common in high-functioning autism and Asperger subjects. The methods used are often violent and potentially lethal or fatal in two cases published. Suicide risk depends on many factors that highlight the vulnerability of these subjects, following autistic and developmental symptoms. Vulnerability complicating the diagnosis of comorbid depressive and anxiety disorders are major factors associated with suicidality. Vulnerability but also directly related to suicidality, since the origin of physical and sexual abuse and victimization by peers assigning them the role of "scapegoat" are both responsible for acting out. Given the diversity of factors involved in the risk of suicide in this population, this does not validate "a" program of intervention, but the intervention of "customized programs". Their implementation should be as early as possible in order to treat

A Synchronisation Method For Informed Spread-Spectrum Audiowatermarking

Directory of Open Access Journals (Sweden)

Pierre-Yves Fulchiron

2003-12-01

Full Text Available Under perfect synchronisation conditions, watermarking schemes employing asymmetric spread-spectrum techniques are suitable for copy-protection of audio signals. This paper proposes to combine the use of a robust psychoacoustic projection for the extraction of a watermark feature vector along with non-linear detection functions optimised with side-information. The new proposed scheme benefits from an increased level of security through the use of asymmetric detectors. We apply this scheme to real audio signals and experimental results show an increased robustness to desynchronisation attacks such as random cropping.

Investigation of influence of electronic irradiation on photoluminescence spectrum and ir-spectrum of porous silicon

International Nuclear Information System (INIS)

Daineko, E.A.; Dihanbayev, K.K.; Akhtar, P.; Hussain, A.

2007-01-01

In this article we study the influence of 2-Mev electron irradiation on porous silicon (PS). Photoluminescence (PL) spectrum and IR-spectrum have been done on both newly-prepared PS samples and samples prepared a year ago after the irradiation. We analyzed PL spectrum for both types of PS samples. The experimental results suggest that the peak position in PL spectrum decreases for newly-prepared PS samples. The size of the nanocrystals calculated by the method of singling out of spectrum components was equal to 3.0-3.2 nm. Porosity of the samples was 60-75%. From IR-spectrum of newly-prepared PS samples wide absorption band was observed at 1100 cm/sup -1/ (Si-O-Si bond). Another peak of Si-O-Si group was observed at 850 cm/sub -1/. Also hydrogen absorption bands were appearing from 2000 to 2200 cm/sup -1/, corresponding to vibration modes SiH, SiH/sub 2/, SiH/sub 3/. As a result of electron irradiation the PL intensity of newly-prepared PS samples decreases abruptly by a factor of 30 without peak shifting. As for the samples prepared a year ago we observed a decrease in the PL intensity by 25-30%. From IR-spectrum of PS samples prepared a year ago it was shown that the intensity of bridge bonds corresponding to absorption band 850 cm/sup -1/, decreases gradually. Our experimental data shows that PS samples stored for longer time have better radiation resistant properties than the newly-prepared PS samples due to the replacement of Si-H bonds with more resistant Si-O bonds. Porous silicon, electrochemical anodizing, photoluminescence spectrum, IR-spectrum, electronic irradiation. (author)

The effect of epilepsy on autistic symptom severity assessed by the social responsiveness scale in children with autism spectrum disorder.

Science.gov (United States)

Ko, Chanyoung; Kim, Namwook; Kim, Eunjoo; Song, Dong Ho; Cheon, Keun-Ah

2016-06-27

As the prevalence of autism spectrum disorders in people with epilepsy ranges from 15 to 47 % (Clarke et al. in Epilepsia 46:1970-1977, 2005), it is speculated that there is a special relationship between the two disorders, yet there has been a lack of systematic studies comparing the behavioral phenotype between autistic individuals and autistic individuals with epilepsy. This study aims to investigate how the co-occurrence of epilepsy and Autism Spectrum Disorder (ASD) affects autistic characteristics assessed by the Social Responsiveness Scale (SRS), which has been used as a measure of autism symptoms in previous studies. In this research we referred to all individuals with Autism or Autistic Disorder as individuals with ASD. We reviewed the complete medical records of 182 participants who presented to a single tertiary care referral center from January 1, 2013 to July 28, 2015, and subsequently received complete child and adolescent psychiatric assessments. Of the 182 participants, 22 were diagnosed with Autism Spectrum Disorder and epilepsy. Types of epilepsy observed in these individuals included complex partial seizure, generalized tonic-clonic seizure, or infantile spasm. Using 'Propensity Score Matching' we selected 44 children, diagnosed with only Autism Spectrum Disorder, whose age, gender, and intelligence quotient (IQ) were closely matched with the 22 children diagnosed with Autism Spectrum Disorder and epilepsy. Social functioning of participants was assessed by the social responsiveness scale, which consists of five categories: social awareness, social cognition, social communication, social motivation, and autistic mannerisms. Bivariate analyses were conducted to compare the ASD participants with epilepsy group with the ASD-only group on demographic and clinical characteristics. Chi square and t test p values were calculated when appropriate. There was no significant difference in age (p = 0.172), gender (p > 0.999), IQ (FSIQ, p = 0.139; VIQ

Sparse random matrices: The eigenvalue spectrum revisited

International Nuclear Information System (INIS)

Semerjian, Guilhem; Cugliandolo, Leticia F.

2003-08-01

We revisit the derivation of the density of states of sparse random matrices. We derive a recursion relation that allows one to compute the spectrum of the matrix of incidence for finite trees that determines completely the low concentration limit. Using the iterative scheme introduced by Biroli and Monasson [J. Phys. A 32, L255 (1999)] we find an approximate expression for the density of states expected to hold exactly in the opposite limit of large but finite concentration. The combination of the two methods yields a very simple geometric interpretation of the tails of the spectrum. We test the analytic results with numerical simulations and we suggest an indirect numerical method to explore the tails of the spectrum. (author)

Autism Spectrum Disorders in Iran

OpenAIRE

Mohammad Reza MOHAMMADI; Maryam SALMANIAN; Shahin AKHONDZADEH

2011-01-01

How to Cite this Article: Mohammadi MR, Salmanian M, Akhondzadeh Sh. Autism Spectrum Disorders in Iran. Iranian Journal of Child Neurology2011;5(4):1-9.ObjectiveAutistic disorder, Asperger syndrome, and PDD-Not Otherwise Specified are subsets of autism spectrum disorders (ASDs), which are characterized by impairments in social communication and stereotyped behavior. This article reviews the prevalence, etiology, diagnosis, and treatment of ASDs in Iran.Materials & MethodsWe searched PubMe...

Use of an improved radiation amplification factor to estimate the effect of total ozone changes on action spectrum weighted irradiances and an instrument response function

Science.gov (United States)

Herman, Jay R.

2010-12-01

Multiple scattering radiative transfer results are used to calculate action spectrum weighted irradiances and fractional irradiance changes in terms of a power law in ozone Ω, U(Ω/200)-RAF, where the new radiation amplification factor (RAF) is just a function of solar zenith angle. Including Rayleigh scattering caused small differences in the estimated 30 year changes in action spectrum-weighted irradiances compared to estimates that neglect multiple scattering. The radiative transfer results are applied to several action spectra and to an instrument response function corresponding to the Solar Light 501 meter. The effect of changing ozone on two plant damage action spectra are shown for plants with high sensitivity to UVB (280-315 nm) and those with lower sensitivity, showing that the probability for plant damage for the latter has increased since 1979, especially at middle to high latitudes in the Southern Hemisphere. Similarly, there has been an increase in rates of erythemal skin damage and pre-vitamin D3 production corresponding to measured ozone decreases. An example conversion function is derived to obtain erythemal irradiances and the UV index from measurements with the Solar Light 501 instrument response function. An analytic expressions is given to convert changes in erythemal irradiances to changes in CIE vitamin-D action spectrum weighted irradiances.

The neutrino mass from beta spectrum (ITEP-85)

International Nuclear Information System (INIS)

Lubimov, V.

1986-01-01

The new cycle of tritium beta spectrum measurements in valine with the ITEP spectrometer is discussed (ITEP-85). The detailed investigation of the total response function (TRF) has been performed. The special run of beta spectrum measurements carried out in a wide energy interval (3.4 KeV) has turned out to be a sensitive mode for the TRF experimental test. The results confirm the indication of the neutrino nonzero mass. 11 refs., 10 figs

Trends in broad-spectrum antibiotic prescribing for children with acute otitis media in the United States, 1998–2004

Directory of Open Access Journals (Sweden)

Gambler Angela S

2009-06-01

Full Text Available Abstract Background Overuse of broad-spectrum antibiotics is associated with antibiotic resistance. Acute otitis media (AOM is responsible for a large proportion of antibiotics prescribed for US children. Rates of broad-spectrum antibiotic prescribing for AOM are unknown. Methods Analysis of the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey, 1998 to 2004 (N = 6,878. Setting is office-based physicians, hospital outpatient departments, and emergency departments. Patients are children aged 12 years and younger prescribed antibiotics for acute otitis media. Main outcome measure is percentage of broad-spectrum antibiotics, defined as amoxicillin/clavulanate, macrolides, cephalosporins and quinolones. Results Broad-spectrum prescribing for acute otitis media increased from 34% of visits in 1998 to 45% of visits in 2004 (P Conclusion Prescribing of broad-spectrum antibiotics for acute otitis media has steadily increased from 1998 to 2004. Associations with non-clinical factors suggest potential for improvement in prescribing practice.

Spectrum analysis with indoor multi-channels gamma-rays spectrometer (NaI(Tl))

International Nuclear Information System (INIS)

Hou Shengli; Fan Weihua

2005-01-01

Two calculational methods for analyzing the spectrum which measured by indoor low background multi-channels gamma-rays spectrometer (Na(Tl)) to get the specific activity of 226 Ra, 232 Th and 40 K of the sample are discussed, they are the spectrum analysis method and the characteristic energy peak method (inverse matrix method) respectively. The sample spectrum are analyzed with the program designed according to the two methods, and compared with the results by HPGe gamma-rays spectrometer, showing that the relative deviation is ≤10% with the two methods. (authors)

Multifractal signal reconstruction based on singularity power spectrum

International Nuclear Information System (INIS)

Xiong, Gang; Yu, Wenxian; Xia, Wenxiang; Zhang, Shuning

2016-01-01

Highlights: • We propose a novel multifractal reconstruction method based on singularity power spectrum analysis (MFR-SPS). • The proposed MFR-SPS method has better power characteristic than the algorithm in Fraclab. • Further, the SPS-ISE algorithm performs better than the SPS-MFS algorithm. • Based on the proposed MFR-SPS method, we can restructure singularity white fractal noise (SWFN) and linear singularity modulation (LSM) multifractal signal, in equivalent sense, similar with the linear frequency modulation(LFM) signal and WGN in the Fourier domain. - Abstract: Fractal reconstruction (FR) and multifractal reconstruction (MFR) can be considered as the inverse problem of singularity spectrum analysis, and it is challenging to reconstruct fractal signal in accord with multifractal spectrum (MFS). Due to the multiple solutions of fractal reconstruction, the traditional methods of FR/MFR, such as FBM based method, wavelet based method, random wavelet series, fail to reconstruct fractal signal deterministically, and besides, those methods neglect the power spectral distribution in the singular domain. In this paper, we propose a novel MFR method based singularity power spectrum (SPS). Supposing the consistent uniform covering of multifractal measurement, we control the traditional power law of each scale of wavelet coefficients based on the instantaneous singularity exponents (ISE) or MFS, simultaneously control the singularity power law based on the SPS, and deduce the principle and algorithm of MFR based on SPS. Reconstruction simulation and error analysis of estimated ISE, MFS and SPS show the effectiveness and the improvement of the proposed methods compared to those obtained by the Fraclab package.

Blind spectrum reconstruction algorithm with L0-sparse representation

International Nuclear Information System (INIS)

Liu, Hai; Zhang, Zhaoli; Liu, Sanyan; Shu, Jiangbo; Liu, Tingting; Zhang, Tianxu

2015-01-01

Raman spectrum often suffers from band overlap and Poisson noise. This paper presents a new blind Poissonian Raman spectrum reconstruction method, which incorporates the L 0 -sparse prior together with the total variation constraint into the maximum a posteriori framework. Furthermore, the greedy analysis pursuit algorithm is adopted to solve the L 0 -based minimization problem. Simulated and real spectrum experimental results show that the proposed method can effectively preserve spectral structure and suppress noise. The reconstructed Raman spectra are easily used for interpreting unknown chemical mixtures. (paper)

Parametric spectro-temporal analyzer (PASTA) for real-time optical spectrum observation

Science.gov (United States)

Zhang, Chi; Xu, Jianbing; Chui, P. C.; Wong, Kenneth K. Y.

2013-06-01

Real-time optical spectrum analysis is an essential tool in observing ultrafast phenomena, such as the dynamic monitoring of spectrum evolution. However, conventional method such as optical spectrum analyzers disperse the spectrum in space and allocate it in time sequence by mechanical rotation of a grating, so are incapable of operating at high speed. A more recent method all-optically stretches the spectrum in time domain, but is limited by the allowable input condition. In view of these constraints, here we present a real-time spectrum analyzer called parametric spectro-temporal analyzer (PASTA), which is based on the time-lens focusing mechanism. It achieves a frame rate as high as 100 MHz and accommodates various input conditions. As a proof of concept and also for the first time, we verify its applications in observing the dynamic spectrum of a Fourier domain mode-locked laser, and the spectrum evolution of a laser cavity during its stabilizing process.

Investigating the autonomic nervous system response to anxiety in children with autism spectrum disorders.

Science.gov (United States)

Kushki, Azadeh; Drumm, Ellen; Pla Mobarak, Michele; Tanel, Nadia; Dupuis, Annie; Chau, Tom; Anagnostou, Evdokia

2013-01-01

Assessment of anxiety symptoms in autism spectrum disorders (ASD) is a challenging task due to the symptom overlap between the two conditions as well as the difficulties in communication and awareness of emotions in ASD. This motivates the development of a physiological marker of anxiety in ASD that is independent of language and does not require observation of overt behaviour. In this study, we investigated the feasibility of using indicators of autonomic nervous system (ANS) activity for this purpose. Specially, the objectives of the study were to 1) examine whether or not anxiety causes significant measurable changes in indicators of ANS in an ASD population, and 2) characterize the pattern of these changes in ASD. We measured three physiological indicators of the autonomic nervous system response (heart rate, electrodermal activity, and skin temperature) during a baseline (movie watching) and anxiety condition (Stroop task) in a sample of typically developing children (n = 17) and children with ASD (n = 12). The anxiety condition caused significant changes in heart rate and electrodermal activity in both groups, however, a differential pattern of response was found between the two groups. In particular, the ASD group showed elevated heart rate during both baseline and anxiety conditions. Elevated and blunted phasic electrodermal activity were found in the ASD group during baseline and anxiety conditions, respectively. Finally, the ASD group did not show the typical decrease in skin temperature in response to anxiety. These results suggest that 1) signals of the autonomic nervous system may be used as indicators of anxiety in children with ASD, and 2) ASD may be associated with an atypical autonomic response to anxiety that is most consistent with sympathetic over-arousal and parasympathetic under-arousal.

The Spectrum Sharing in Cognitive Radio Networks Based on Competitive Price Game

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Y. B. Li

2012-09-01

Full Text Available The competitive price game model is used to analyze the spectrum sharing problem in the cognitive radio networks, and the spectrum sharing problem with the constraints of available spectrum resource from primary users is further discussed in this paper. The Rockafeller multiplier method is applied to deal with the constraints of available licensed spectrum resource, and the improved profits function is achieved, which can be used to measure the impact of shared spectrum price strategies on the system profit. However, in the competitive spectrum sharing problem of practical cognitive radio network, primary users have to determine price of the shared spectrum without the acknowledgement of the other primary user’s price strategies. Thus a fast gradient iterative calculation method of equilibrium price is proposed, only with acknowledgement of the price strategies of shared spectrum during last cycle. Through the adaptive iteration at the direction with largest gradient of improved profit function, the equilibrium price strategies can be achieved rapidly. It can also avoid the predefinition of adjustment factor according to the parameters of communication system in conventional linear iteration method. Simulation results show that the proposed competitive price spectrum sharing model can be applied in the cognitive radio networks with constraints of available licensed spectrum, and it has better convergence performance.

Hoarding in Youth with Autism Spectrum Disorders and Anxiety: Incidence, Clinical Correlates, and Behavioral Treatment Response.

Science.gov (United States)

Storch, Eric A; Nadeau, Joshua M; Johnco, Carly; Timpano, Kiara; McBride, Nicole; Jane Mutch, P; Lewin, Adam B; Murphy, Tanya K

2016-05-01

This study examined the nature and correlates of hoarding among youth with autism spectrum disorders (ASD). Forty children with ASD and a comorbid anxiety disorder were administered a battery of clinician-administered measures assessing presence of psychiatric disorders and anxiety severity. Parents completed questionnaires related to child hoarding behaviors, social responsiveness, internalizing and externalizing behaviors, and functional impairment. We examined the impact of hoarding behaviors on treatment response in a subsample of twenty-six youth who completed a course of personalized cognitive-behavioral therapy targeting anxiety symptoms. Hoarding symptoms were common and occurred in a clinically significant manner in approximately 25 % of cases. Overall hoarding severity was associated with increased internalizing and anxiety/depressive symptoms, externalizing behavior, and attention problems. Discarding items was associated with internalizing and anxious/depressive symptoms, but acquisition was not. Hoarding decreased following cognitive-behavioral therapy but did not differ between treatment responders and non-responders. These data are among the first to examine hoarding among youth with ASD; implications of study findings and future directions are highlighted.

Neutron response study

International Nuclear Information System (INIS)

Endres, G.W.R.; Fix, J.J.; Thorson, M.R.; Nichols, L.L.

1981-01-01

Neutron response of the albedo type dosimeter is strongly dependent on the energy of the incident neutrons as well as the moderating material on the backside of the dosimeter. This study characterizes the response of the Hanford dosimeter for a variety of neutron energies for both a water and Rando phantom (a simulated human body consisting of an actual human skeleton with plastic for body muscles and certain organs). The Hanford dosimeter response to neutrons of different energies is typical of albedo type dosimeters. An approximate two orders of magnitude difference in response is observed between neutron energies of 100 keV and 10 MeV. Methods were described to compensate for the difference in dosimeter response between a laboratory neutron spectrum and the different spectra encountered at various facilities in the field. Generally, substantial field support is necessary for accurate neutron dosimetry

End of multifield inflation and the perturbation spectrum

International Nuclear Information System (INIS)

Gong, Jinn-Ouk

2007-01-01

We investigate the dynamics of inflation models driven by multiple, decoupled scalar fields and calculate the Hubble parameter and the amplitude of the lightest field at the end of inflation which may be responsible for interesting, or possibly dangerous cosmological consequences after inflation. The results are very simple and similar to those of the single field inflation, mainly depending on the underlying spectrum of the masses. The mass distribution is heavily constrained by the power spectrum of density perturbations P and the spectral index n s . The overall mass scale gives the amplitude of P, and n s is affected by the number of fields and the spacing between masses in the distribution. The dropout effect of the massive fields makes the perturbation spectrum typically redder than the single field inflation spectrum. We illustrate this using two different mass distributions

Pivotal response treatment for autism spectrum disorder: current perspectives

Directory of Open Access Journals (Sweden)

Lei J

2017-06-01

Full Text Available Jiedi Lei, Pamela Ventola Yale Child Study Center, Yale University School of Medicine, New Haven, CT, USA Abstract: Pivotal response treatment (PRT is an evidence-based behavioral intervention based on applied behavior analysis principles aimed to improve social communication skills in individuals with autism spectrum disorder (ASD. PRT adopts a more naturalistic approach and focuses on using a number of strategies to help increase children’s motivation during intervention. Since its conceptualization, PRT has received much empirical support for eliciting therapeutic gains in greater use of functional social communication skills in individuals with ASD. Building upon the empirical evidence supporting PRT, recent advancements have increasingly turned to using interdisciplinary research integrating neuroimaging techniques and behavioral measures to help identify objective biomarkers of treatment, which have two primary purposes. First, neuroimaging results can help characterize how PRT may elicit change, and facilitate partitioning of the heterogeneous profiles of neural mechanisms underlying similar profile of behavioral changes observed over PRT. Second, neuroimaging provides an objective means to both map and track how biomarkers may serve as reliable and sensitive predictors of responder profiles to PRT, assisting clinicians to identify who will most likely benefit from PRT. Together, a better understanding of both mechanisms of change and predictors of responder profile will help PRT to serve as a more precise and targeted intervention for individuals with ASD, thus moving towards the goal of precision medicine and improving quality of care. This review focuses on the recent emerging neuroimaging evidences supporting PRT, offering current perspectives on the importance of interdisciplinary research to help clinicians better understand how PRT works and predict who will respond to PRT. Keywords: PRT, ASD, biomarkers, neuroimaging

Planetary method to measure the neutrons spectrum in lineal accelerators of medical use; Metodo planetario para medir el espectro de neutrones en aceleradores lineales de uso medico

Energy Technology Data Exchange (ETDEWEB)

Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Benites R, J. L., E-mail: fermineutron@yahoo.com [Centro Estatal de Cancerologia de Nayarit, Servicio de Seguridad Radiologica, Calzada de la Cruz 118 Sur, 63000 Tepic, Nayarit (Mexico)

2014-08-15

A novel procedure to measure the neutrons spectrum originated in a lineal accelerator of medical use has been developed. The method uses a passive spectrometer of Bonner spheres. The main advantage of the method is that only requires of a single shot of the accelerator. When this is used around a lineal accelerator is necessary to operate it under the same conditions so many times like the spheres that contain the spectrometer, activity that consumes enough time. The developed procedure consists on situating all the spheres of the spectrometer at the same time and to realize the reading making a single shot. With this method the photo neutrons spectrum produced by a lineal accelerator Varian ix of 15 MV to 100 cm of the isocenter was determined, with the spectrum is determined the total flow and the ambient dose equivalent. (Author)

A new method of testing space-based high-energy electron detectors with radioactive electron sources

Energy Technology Data Exchange (ETDEWEB)

Zhang, S.Y. [National Space Science Center, Chinese Academy of Sciences, Beijing (China); Beijing Key Laboratory of Space Environment Exploration, Beijing (China); Shen, G.H., E-mail: shgh@nssc.ac.cn [National Space Science Center, Chinese Academy of Sciences, Beijing (China); Beijing Key Laboratory of Space Environment Exploration, Beijing (China); Sun, Y., E-mail: sunying@nssc.ac.cn [National Space Science Center, Chinese Academy of Sciences, Beijing (China); Beijing Key Laboratory of Space Environment Exploration, Beijing (China); Zhou, D.Z., E-mail: dazhuang.zhou@gmail.com [National Space Science Center, Chinese Academy of Sciences, Beijing (China); Beijing Key Laboratory of Space Environment Exploration, Beijing (China); Zhang, X.X., E-mail: xxzhang@cma.gov.cn [National Center for Space Weather, Beijing (China); Li, J.W., E-mail: lijw@cma.gov.cn [National Center for Space Weather, Beijing (China); Huang, C., E-mail: huangc@cma.gov.cn [National Center for Space Weather, Beijing (China); Zhang, X.G., E-mail: zhangxg@nssc.ac.cn [National Space Science Center, Chinese Academy of Sciences, Beijing (China); Beijing Key Laboratory of Space Environment Exploration, Beijing (China); Dong, Y.J., E-mail: dyj@nssc.ac.cn [National Space Science Center, Chinese Academy of Sciences, Beijing (China); Beijing Key Laboratory of Space Environment Exploration, Beijing (China); Zhang, W.J., E-mail: zhangreatest@163.com [National Space Science Center, Chinese Academy of Sciences, Beijing (China); Beijing Key Laboratory of Space Environment Exploration, Beijing (China); Zhang, B.Q., E-mail: zhangbinquan@nssc.ac.cn [National Space Science Center, Chinese Academy of Sciences, Beijing (China); Beijing Key Laboratory of Space Environment Exploration, Beijing (China); Shi, C.Y., E-mail: scy@nssc.ac.cn [National Space Science Center, Chinese Academy of Sciences, Beijing (China); Beijing Key Laboratory of Space Environment Exploration, Beijing (China)

2016-05-01

Space-based electron detectors are commonly tested using radioactive β-sources which emit a continuous spectrum without spectral lines. Therefore, the tests are often to be considered only qualitative. This paper introduces a method, which results in more than a qualitative test even when using a β-source. The basic idea is to use the simulated response function of the instrument to invert the measured spectrum and compare this inverted spectrum with a reference spectrum obtained from the same source. Here we have used Geant4 to simulate the instrument response function (IRF) and a 3.5 mm thick Li-drifted Si detector to obtain the reference {sup 90}Sr/{sup 90}Yi source spectrum to test and verify the geometric factors of the Omni-Direction Particle Detector (ODPD) on the Tiangong-1 (TG-1) and Tiangong-2 (TG-2) spacecraft. The TG spacecraft are experimental space laboratories and prototypes of the Chinese space station. The excellent agreement between the measured and reference spectra demonstrates that this test method can be used to quantitatively assess the quality of the instrument. Due to its simplicity, the method is faster and therefore more efficient than traditional full calibrations using an electron accelerator.

A new method of testing space-based high-energy electron detectors with radioactive electron sources

International Nuclear Information System (INIS)

Zhang, S.Y.; Shen, G.H.; Sun, Y.; Zhou, D.Z.; Zhang, X.X.; Li, J.W.; Huang, C.; Zhang, X.G.; Dong, Y.J.; Zhang, W.J.; Zhang, B.Q.; Shi, C.Y.

2016-01-01

Space-based electron detectors are commonly tested using radioactive β-sources which emit a continuous spectrum without spectral lines. Therefore, the tests are often to be considered only qualitative. This paper introduces a method, which results in more than a qualitative test even when using a β-source. The basic idea is to use the simulated response function of the instrument to invert the measured spectrum and compare this inverted spectrum with a reference spectrum obtained from the same source. Here we have used Geant4 to simulate the instrument response function (IRF) and a 3.5 mm thick Li-drifted Si detector to obtain the reference "9"0Sr/"9"0Yi source spectrum to test and verify the geometric factors of the Omni-Direction Particle Detector (ODPD) on the Tiangong-1 (TG-1) and Tiangong-2 (TG-2) spacecraft. The TG spacecraft are experimental space laboratories and prototypes of the Chinese space station. The excellent agreement between the measured and reference spectra demonstrates that this test method can be used to quantitatively assess the quality of the instrument. Due to its simplicity, the method is faster and therefore more efficient than traditional full calibrations using an electron accelerator.

Mutational spectrum of phenylketonuria in Jiangsu province.

Science.gov (United States)

Chen, Ya-fen; Jia, Hai-tao; Chen, Zhong-hai; Song, Jia-ping; Liang, Yu; Pei, Jing-jing; Wu, Zhi-jun; Wang, Jing; Qiu, Ya-li; Liu, Gang; Sun, Dong-mei; Jiang, Xin-ye

2015-10-01

Phenylketonuria (PKU) is caused by variants in the phenylalanine hydroxylase (PAH) gene. We systematically investigated all 13 exons of the PAH gene and their flanking introns in 31 unrelated patients and their parents using next-generation sequencing (NGS). A total of 33 different variants were identified in 58 of 62 mutant PAH alleles. The prevalent variants with a relative frequency of 5 % or more were c.721C > T, c.1068C > A, c.611A > G, c.1197A > T, c.728G > A, c.331C > T, and c.442-1G > A. One novel variant was identified in this study-c.699C > G. We studied genotype-phenotype correlations using the Guldberg arbitrary value (AV) system, which revealed a consistency rate of 38 % (8/21) among the 21 predicted phenotypes. The genotype-based prediction of BH4 responsiveness was also evaluated, and 14 patients (45.2 %) were predicted to be BH4 responsive. This study presents the spectrum of PAH variants in Jiangsu province. The information obtained from the genotype-based prediction of BH4 responsiveness might be used for the rational selection of candidates for BH4 testing. • Phenylketonuria (PKU) is caused by variants in the phenylalanine hydroxylase (PAH) gene. • The spectrum of PAH variants in different Chinese populations has been reported. What is new: • This is the first report on the spectrum of PAH variants in Jiangsu province. • This study identified one novel PAH variant-c.699C>G-and and tries to show a genotype-phenotype relationship also regarding BH4-responsiveness.

Natural gamma ray spectrum analysis technique

International Nuclear Information System (INIS)

Chevalier, P.; Seeman, B.

1976-01-01

In accordance with an illustrative embodiment of the present invention, a method and apparatus is disclosed for determining the presence of a selected number of naturally radioactive materials in an earth formation from the spectrum of natural gamma radiation emitted by the materials in the formation by deriving representations of portions of the detected gamma radiation spectrum and combining the representations to determine therefrom the presence of the selected materials

Spectrum monitoring procedures and techniques

Science.gov (United States)

1990-07-01

The first step towards operating an emitter on a test range is to contact the local frequency manager to establish a schedule. Since restricted radio frequency bands and operations are different at each test range location, most testing is accomplished by sharing the spectrum available with all range users. The telemetry bands in particular require spectrum activity scheduling. The objective is to resolve scheduling conflicts prior to operations. When two programs or projects request to use the same spectrum, their activity can be separated by quard bands, discrete frequencies, time, or operating locations (terrain masking). Priorities assigned to each program usually dictate which program will be scheduled first; however, use of priorities to schedule activities should be avoided and only considered as a last resort. When a scheduling conflict cannot be resolved using these techniques, it is brought to the attention of the responsible program managers. When scheduling activities involve other federal or nonfederal agencies, it is in the best interest of program managers to be as flexible as possible.

The effect of sung speech on socio-communicative responsiveness in children with autism spectrum disorders.

Science.gov (United States)

Paul, Arkoprovo; Sharda, Megha; Menon, Soumini; Arora, Iti; Kansal, Nayantara; Arora, Kavita; Singh, Nandini C

2015-01-01

There is emerging evidence to demonstrate the efficacy of music-based interventions for improving social functioning in children with Autism Spectrum Disorders (ASD). While this evidence lends some support in favor of using song over spoken directives in facilitating engagement and receptive intervention in ASD, there has been little research that has investigated the efficacy of such stimuli on socio-communicative responsiveness measures. Here, we present preliminary results from a pilot study which tested whether sung instruction, as compared to spoken directives, could elicit greater number of socio-communicative behaviors in young children with ASD. Using an adapted single-subject design, three children between the ages of 3 and 4 years, participated in a programme consisting of 18 sessions, of which 9 were delivered with spoken directives and 9 with sung. Sessions were counterbalanced and randomized for three play activities-block matching, picture matching and clay play. All sessions were video-recorded for post-hoc observational coding of three behavioral metrics which included performance, frequency of social gesture and eye contact. Analysis of the videos by two independent raters indicated increased socio-communicative responsiveness in terms of frequency of social gesture as well as eye contact during sung compared to spoken conditions, across all participants. Our findings suggest that sung directives may play a useful role in engaging children with ASD and also serve as an effective interventional medium to enhance socio-communicative responsiveness.

The effect of sung speech on socio-communicative responsiveness in children with Autism Spectrum Disorders

Directory of Open Access Journals (Sweden)

Arkoprovo ePaul

2015-10-01

Full Text Available There is emerging evidence to demonstrate the efficacy of music based interventions for improving social functioning in children with Autism Spectrum Disorders (ASD. While this evidence lends some support in favour of using song over spoken directives in facilitating engagement and receptive intervention in ASD, there has been little research that has investigated the efficacy of such stimuli on socio-communicative responsiveness measures. Here, we present preliminary results from a pilot study which tested whether sung instruction, as compared to spoken directives, could elicit greater number of socio-communicative behaviours in young children with ASD. Using an adapted single-subject design, three children between the ages of 3 and 4 years, participated in a programme consisting of 18 sessions, of which 9 were delivered with spoken directives and 9 with sung. Sessions were counterbalanced and randomized for three play activities - block matching, picture matching and clay play. All sessions were video-recorded for post-hoc observational coding of three behavioural metrics which included performance, frequency of social gesture and eye contact. Analysis of the videos by two independent raters indicated increased socio-communicative responsiveness in terms of frequency of social gesture as well as eye contact during sung compared to spoken conditions across all participants. Our findings suggest that sung directives may play a useful role in engaging children with ASD and also serve as an effective interventional medium to enhance socio-communicative responsiveness.

Three-item Direct Observation Screen (TIDOS) for autism spectrum disorder.

Science.gov (United States)

Oner, Pinar; Oner, Ozgur; Munir, Kerim

2014-08-01

We compared ratings on the Three-Item Direct Observation Screen test for autism spectrum disorders completed by pediatric residents with the Social Communication Questionnaire parent reports as an augmentative tool for improving autism spectrum disorder screening performance. We examined three groups of children (18-60 months) comparable in age (18-24 month, 24-36 month, 36-60 preschool subgroups) and gender distribution: n = 86 with Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.) autism spectrum disorders; n = 76 with developmental delay without autism spectrum disorders; and n = 97 with typical development. The Three-Item Direct Observation Screen test included the following (a) Joint Attention, (b) Eye Contact, and (c) Responsiveness to Name. The parent Social Communication Questionnaire ratings had a sensitivity of .73 and specificity of .70 for diagnosis of autism spectrum disorders. The Three-Item Direct Observation Screen test item Joint Attention had a sensitivity of .82 and specificity of .90, Eye Contact had a sensitivity of .89 and specificity of .91, and Responsiveness to Name had a sensitivity of .67 and specificity of .87. In the Three-Item Direct Observation Screen test, having at least one of the three items positive had a sensitivity of .95 and specificity of .85. Age, diagnosis of autism spectrum disorder, and developmental level were important factors affecting sensitivity and specificity. The results indicate that augmentation of autism spectrum disorder screening by observational items completed by trained pediatric-oriented professionals can be a highly effective tool in improving screening performance. If supported by future population studies, the results suggest that primary care practitioners will be able to be trained to use this direct procedure to augment screening for autism spectrum disorders in the community. © The Author(s) 2013.

Frequency spectrum method-based stress analysis for oil pipelines in earthquake disaster areas.

Directory of Open Access Journals (Sweden)

Xiaonan Wu

Full Text Available When a long distance oil pipeline crosses an earthquake disaster area, inertial force and strong ground motion can cause the pipeline stress to exceed the failure limit, resulting in bending and deformation failure. To date, researchers have performed limited safety analyses of oil pipelines in earthquake disaster areas that include stress analysis. Therefore, using the spectrum method and theory of one-dimensional beam units, CAESAR II is used to perform a dynamic earthquake analysis for an oil pipeline in the XX earthquake disaster area. This software is used to determine if the displacement and stress of the pipeline meet the standards when subjected to a strong earthquake. After performing the numerical analysis, the primary seismic action axial, longitudinal and horizontal displacement directions and the critical section of the pipeline can be located. Feasible project enhancement suggestions based on the analysis results are proposed. The designer is able to utilize this stress analysis method to perform an ultimate design for an oil pipeline in earthquake disaster areas; therefore, improving the safe operation of the pipeline.

Frequency spectrum method-based stress analysis for oil pipelines in earthquake disaster areas.

Science.gov (United States)

Wu, Xiaonan; Lu, Hongfang; Huang, Kun; Wu, Shijuan; Qiao, Weibiao

2015-01-01

When a long distance oil pipeline crosses an earthquake disaster area, inertial force and strong ground motion can cause the pipeline stress to exceed the failure limit, resulting in bending and deformation failure. To date, researchers have performed limited safety analyses of oil pipelines in earthquake disaster areas that include stress analysis. Therefore, using the spectrum method and theory of one-dimensional beam units, CAESAR II is used to perform a dynamic earthquake analysis for an oil pipeline in the XX earthquake disaster area. This software is used to determine if the displacement and stress of the pipeline meet the standards when subjected to a strong earthquake. After performing the numerical analysis, the primary seismic action axial, longitudinal and horizontal displacement directions and the critical section of the pipeline can be located. Feasible project enhancement suggestions based on the analysis results are proposed. The designer is able to utilize this stress analysis method to perform an ultimate design for an oil pipeline in earthquake disaster areas; therefore, improving the safe operation of the pipeline.

Neutron Spectrum Parameters In Inner Irradiation Channel Of The Nigeria Research Reactor-1 (NIRR-1) For Use In Absolute And KO-NAA Methods

International Nuclear Information System (INIS)

Jonah, S.A; Balogun, G.I; Mayaki, M.C.

2004-01-01

In Nigeria, the first Nuclear Reactor achieved critically on February 03, 2004 at about 11:35 GMT and has been commissioned or training and research. It is a Miniature Neutron Source Reactor (MNSR), code-named Nigeria Research Reactor-1 (NIRR-1). NIRR-1 has a tan-in-pool structural configuration and a nominal thermal power rating of 30 Kw. With a built-in clean old core excess reactivity of 3.77 mk determined during the on-site zero and critically experimental, the reactor can operate for a n.cm-2 .s-1 in the inner irradiation channels). Under these conditions, the reactor can operate with the same fuel loading for over ten years with a burn-up of <1%. A detailed description of operating characteristics for NIRR-1, measured during the on-site zero-power and criticality experiments has been given elsewhere. In order to extend its utilization to include absolute and ko-NAA methods, the neutron spectrum parameters in the irradiation channels: power and critically experiments has been given elsewhere. In order to extend it's the irradiation channels: thermal-to-epithermal flux ration, F; and epithermal flux shape factor, a in both the inner and outer irradiation channels must be determined experimentally. In this work, we have developed and experimental procedure for monitoring the neutron spectrum parameters in an inner irradiation channel based on irradiation and gamma-ray counting of detector foils via (n,y), (n,p) and (n,a) dosimetry reactions. Results obtained indicate that a thermal neutron flux of (5.14+-0.02) x 1011 n/c m2.s determined by foil activation method in the inner irradiation channel, B2, at a power level of 15.5 kw corresponds to the flux indicators on the control console and the micro-computer control system respectively. Other parameters of the neutron spectrum determined for inner irradiation channel B2, are: a -0.0502+0.003; 18.92+-0.14; F = 3.87=0.23. The method was validated through the comparison of our result with published neutron spectrum

Resource Distribution Approaches in Spectrum Sharing Systems

Directory of Open Access Journals (Sweden)

Friedrich K. Jondral

2008-05-01

Full Text Available It is increasingly difficult to satisfy growing demands for spectrum with the conventional policy of fixed spectrum allocation. To overcome this problem, flexible/dynamic spectrum sharing methods that can significantly improve spectrum utilization of the spectrum have gained increasing interest recently. This paper presents two dynamic spectrum sharing approaches, a centralized and a decentralized one. The centralized approach is based on hierarchical trading. Each level of hierarchy is composed of “markets” that are associated with a certain spatial area and trading occurrence frequency, whereas area size and trading occurrence frequency depend on the hierarchy level. The decentralized approach is based on game-theory. There, it is assumed that the operators are averse to unequal payoffs and act unselfishly, enabling a stable and sustainable community. Numerical results show that, in the observed scenario, both proposals outperform the reference case of fixed resource allocation significantly in terms of utilized bandwidth. Whereas, negotiation costs for spectrum brokerage appear in the centralized approach, nonnegligible amounts of spectrum are lost in the decentralized approach due to collisions. Thus, a hybrid of centralized and decentralized approach that exploits the benefits of both is also considered.

Vision-based measurement system for structural vibration monitoring using non-projection quasi-interferogram fringe density enhanced by spectrum correction method

International Nuclear Information System (INIS)

Zhong, Jianfeng; Zhong, Shuncong; Zhang, Qiukun; Lu, Huancai; Zhuang, Yizhou; Fu, Xinbin

2017-01-01

A non-projection fringe vision measurement system suitable for vibration monitoring was proposed by using the concept of a 2D optical coherence vibration tomography (2D-OCVT) technique. An artificial quasi-interferogram fringe pattern (QIFP), similar to the interferogram of the 2D-OCVT system, was pasted onto the surface of a vibrating structure as a sensor. Image sequences of the QIFP were captured by a high-speed CMOS camera that worked as a detector. It was possible to obtain both the in-plane and out-of-plane vibration simultaneously. The in-plane vibration was obtained by tracking the center of the imaged QIFP using an image cross-correlation method, whilst the out-of-plane vibration was obtained from the changes in period density of the imaged QIFP. The influence of the noise sources from the CMOS image sensor, together with the effect of the imaging distance, the period density of the QIFP and also the key parameters of the fringe density enhanced by the spectrum correction method on the accuracy of the displacement measurement, were investigated by numerical simulations and experiments. Compared with the results from a conventional accelerometer-based measurement system, the proposed method was demonstrated to be an effective and accurate technique for measuring structural vibration without introducing any extra mass from the accelerometer. The significant advantages of this method include its simple installation and real-time dynamic response measurement capability, making the measurement system ideal for the low- and high-frequency vibration monitoring of engineering structures. (paper)

Neurofeedback in Autism Spectrum Disorders

Science.gov (United States)

Holtmann, Martin; Steiner, Sabina; Hohmann, Sarah; Poustka, Luise; Banaschewski, Tobias; Bolte, Sven

2011-01-01

Aim: To review current studies on the effectiveness of neurofeedback as a method of treatment of the core symptoms of autism spectrum disorders (ASD). Method: Studies were selected based on searches in PubMed, Ovid MEDLINE, EMBASE, ERIC, and CINAHL using combinations of the following keywords: "Neurofeedback" OR "EEG Biofeedback" OR "Neurotherapy"…

Seismic design and analysis methods

International Nuclear Information System (INIS)

Varpasuo, P.

1993-01-01

Seismic load is in many areas of the world the most important loading situation from the point of view of structural strength. Taking this into account it is understandable, that there has been a strong allocation of resources in the seismic analysis during the past ten years. In this study there are three areas of the center of gravity: (1) Random vibrations; (2) Soil-structure interaction and (3) The methods for determining structural response. The solution of random vibration problems is clarified with the aid of applications in this study and from the point of view of mathematical treatment and mathematical formulations it is deemed sufficient to give the relevant sources. In the soil-structure interaction analysis the focus has been the significance of frequency dependent impedance functions. As a result it was obtained, that the description of the soil with the aid of frequency dependent impedance functions decreases the structural response and it is thus always the preferred method when compared to more conservative analysis types. From the methods to determine the C structural response the following four were tested: (1) The time history method; (2) The complex frequency-response method; (3) Response spectrum method and (4) The equivalent static force method. The time history appeared to be the most accurate method and the complex frequency-response method did have the widest area of application. (orig.). (14 refs., 35 figs.)

PERFORMANCE OPTIMIZATION OF COGNITIVE RADIO WITH WIDEBAND SPECTRUM SENSING

Directory of Open Access Journals (Sweden)

E. Saraniya

2014-09-01

Full Text Available Cognitive radio (CR technology allows the unlicensed user to access the licensed spectrum bands. Spectrum sensing is an essential function in cognitive radio to detect the spectrum holes and opportunistically use the underutilized frequency bands without causing interference to primary user (PU. In this paper we are maximizing the throughput capacity of cognitive radio user and hence the performance of spectrum sensing and protection to licensed user improves over a wideband spectrum sensing band. The simulation of cognitive radio is done by analyzing the performance of energy detector spectrum sensing technique to detect primary user and to formulate the optimization using multiband joint detection method (MJD to achieve suitable trade- off between secondary user access and primary user network. The main aim of this paper is to maximize the probability of detection and to decrease the probabilities of miss detection and false alarm. To maximize the throughput it requires minimizing the throughput loss caused by miss detection and the significant reduction in probability of false alarm helps in achieving the spectral efficiency from the secondary user’s perspective. The simulation results show that the performance increases with the MJD method.

Adult Autism Subthreshold Spectrum (AdAS Spectrum): Validation of a questionnaire investigating subthreshold autism spectrum.

Science.gov (United States)

Dell'Osso, L; Gesi, C; Massimetti, E; Cremone, I M; Barbuti, M; Maccariello, G; Moroni, I; Barlati, S; Castellini, G; Luciano, M; Bossini, L; Rocchetti, M; Signorelli, M; Aguglia, E; Fagiolini, A; Politi, P; Ricca, V; Vita, A; Carmassi, C; Maj, M

2017-02-01

Increasing literature has shown the usefulness of a dimensional approach to autism. The present study aimed to determine the psychometric properties of the Adult Autism Subthreshold Spectrum (AdAS Spectrum), a new questionnaire specifically tailored to assess subthreshold forms of autism spectrum disorder (ASD) in adulthood. 102 adults endorsing at least one DSM-5 symptom criterion for ASD (ASDc), 143 adults diagnosed with a feeding and eating disorder (FED), and 160 subjects with no mental disorders (CTL), were recruited from 7 Italian University Departments of Psychiatry and administered the following: SCID-5, Autism-Spectrum Quotient (AQ), Ritvo Autism and Asperger Diagnostic Scale 14-item version (RAADS-14), and AdAS Spectrum. The AdAS Spectrum demonstrated excellent internal consistency for the total score (Kuder-Richardson's coefficient=.964) as well as for five out of seven domains (all coefficients>.80) and sound test-retest reliability (ICC=.976). The total and domain AdAS Spectrum scores showed a moderate to strong (>.50) positive correlation with one another and with the AQ and RAADS-14 total scores. ASDc subjects reported significantly higher AdAS Spectrum total scores than both FED (pcriteria (FED 0 ) and those with one ASD symptom criterion (FED 1 ) , a gradient of severity in AdAS Spectrum scores from CTL subjects to ASD patients, across FED 0 , ASD 1 , FED 1 was shown. The AdAS Spectrum showed excellent internal consistency and test-retest reliability and strong convergent validity with alternative dimensional measures of ASD. The questionnaire performed differently among the three diagnostic groups and enlightened some significant effects of gender in the expression of autistic traits. Copyright © 2016 Elsevier Inc. All rights reserved.

The Study of Radio Flux Density Variations of the Quasar OJ 287 by the Wavelet and the Singular Spectrum Methods

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Donskykh Ganna

2016-06-01

Full Text Available Flux density variations of the extragalactic radio source OJ 287 are studied by applying the wavelet and the singular spectrum methods to the long-term monitoring data at 14.5, 8.0 and 4.8 GHz acquired at the University of Michigan Radio Astronomy Observatory during 40 years. This monitoring significantly supplements the episodic VLBI data. The wavelet analysis at all three frequencies revealed the presence of quasiperiods within the intervals 6.0–7.4 and 1.2–1.8 years. The singular spectrum analysis revealed the presence of quasiperiods within the intervals 6–10 and 1.6–4.0 years. For each quasiperiod the time interval of its existence was determined.

Development of Educational Simulation on Spectrum of HPGe Detector and Implementation of Education Program

International Nuclear Information System (INIS)

Seo, K. W.; Joo, Y. C.; Ji, Y. J.; Lee, M. O.; Lee, S. Y.; Jun, Y. K.

2005-12-01

In this development, characteristics of Aptec, Genie2000(Canberra Co, USA), GammaVision(Ortec Co, USA) which are usually used in Korea radioactive measure laboratory, such as peak search, peak fitting, central area position and area calculation, spectrum correction and method for radioactive calculation are included. And radioactive source geometry, absorption of sample itself, methods for correcting coincidence summing effect is developed and the result effected on spectrum analysis teaching material. Developed simulation HPGe detector spectrum are spectrum for correction, spectrum for correcting radio source-detection duration geometry, sample spectrum which need self absorption correction of radio source, peak search spectrum for optimizing peak search offset setting and background spectrum. These spectrum are made similar to real spectrum by processing peak and background which were measured from mix standard volume radio source. Spectrum analysis teaching material is developed more focus on practical thing than theoretical thing, simulation spectrum must be used in spectrum analysis practise. Optimal method for spectrum analysis condition, spectrum correction, Geometry correction and background spectrum analysis are included in teaching material and also ANSI N42 recommended 'Spectrum analysis program test' procedure is included too. Aptec, Genie2000, Gamma Vision software manuals are included in appendix. In order to check the text of developed simulation on spectrum of HPGe detector, in 2004 and 2005, these was implemented in the other regular course as a course for superviser of the handling with RI. And the text and practical procedure were reviewed through the course and were revised

The spectrum of axisymmetric torsional Alfven waves

International Nuclear Information System (INIS)

Sy, W.N.

1977-03-01

The spectrum of axisymmetric torsional Alfven waves propagating in a cylindrical, non-uniform, resistive plasma waveguide has been analysed by a method of singular perturbations. A simple condition has been derived which predicts whether the spectrum is continuous or discrete under given physical conditions. Application of this result to resolve an apparent discrepancy in experimental observations is briefly discussed. (Author)

A nodal method based on the response-matrix method

International Nuclear Information System (INIS)

Cunha Menezes Filho, A. da; Rocamora Junior, F.D.

1983-02-01

A nodal approach based on the Response-Matrix method is presented with the purpose of investigating the possibility of mixing two different allocations in the same problem. It is found that the use of allocation of albedo combined with allocation of direct reflection produces good results for homogeneous fast reactor configurations. (Author) [pt

High-Frequency Axial Fatigue Test Procedures for Spectrum Loading

Science.gov (United States)

2016-07-20

cycle runout limit. PURPOSE 2. To develop the capability to perform High-Frequency (H-F) Spectrum Fatigue tests, an in- house Basic and...response of the test specimen to the command input signal for load cycling . These cycle -by- cycle errors accumulate over the life of the test specimen...fatigue life model. It is expected that the cycle -by- cycle P-V error may vary substantially depending on the load spectrum content, the compensation

The interior transmission spectrum in one dimension

International Nuclear Information System (INIS)

Hickmann, Kyle S

2012-01-01

This paper seeks conditions on acoustic profiles c(x) and b(x) which imply the existence of intervals free of transmission eigenvalues. The existence of intervals free of transmission eigenvalues has important implications in the question of unique recovery of the acoustic profile for inverse acoustic scattering theory using the linear sampling method and for the inverse source problem in thermoacoustic tomography. We examine the interior transmission spectrum relative to two acoustic profiles on the unit interval. This research includes the case when the difference of the two acoustic profiles changes sign and is, to the author's knowledge, the only work to date on the interior transmission spectrum allowing this behavior. It is shown that for a large class of acoustic profiles the transmission spectrum is asymptotically sparse. The spectrum exhibits three distinct types of behavior dependent on the relation of the two acoustic profiles. Numerical examples of each type of behavior are given which show how the transmission eigenvalues are distributed depending on the relation between c(x) and b(x). Our method of study is to reduce the interior transmission problem on [0, 1] to a problem of finding roots of a determinant of fundamental solutions to a Sturm–Liouville problem. The asymptotic expansion of solutions of the Sturm–Liouville problem then allows us to analyze properties of the transmission spectrum for large values of the wavenumber. (paper)

Inferring Weighted Directed Association Networks from Multivariate Time Series with the Small-Shuffle Symbolic Transfer Entropy Spectrum Method

Directory of Open Access Journals (Sweden)

Yanzhu Hu

2016-09-01

Full Text Available Complex network methodology is very useful for complex system exploration. However, the relationships among variables in complex systems are usually not clear. Therefore, inferring association networks among variables from their observed data has been a popular research topic. We propose a method, named small-shuffle symbolic transfer entropy spectrum (SSSTES, for inferring association networks from multivariate time series. The method can solve four problems for inferring association networks, i.e., strong correlation identification, correlation quantification, direction identification and temporal relation identification. The method can be divided into four layers. The first layer is the so-called data layer. Data input and processing are the things to do in this layer. In the second layer, we symbolize the model data, original data and shuffled data, from the previous layer and calculate circularly transfer entropy with different time lags for each pair of time series variables. Thirdly, we compose transfer entropy spectrums for pairwise time series with the previous layer’s output, a list of transfer entropy matrix. We also identify the correlation level between variables in this layer. In the last layer, we build a weighted adjacency matrix, the value of each entry representing the correlation level between pairwise variables, and then get the weighted directed association network. Three sets of numerical simulated data from a linear system, a nonlinear system and a coupled Rossler system are used to show how the proposed approach works. Finally, we apply SSSTES to a real industrial system and get a better result than with two other methods.

Augmented reality social story for autism spectrum disorder

Science.gov (United States)

Syahputra, M. F.; Arisandi, D.; Lumbanbatu, A. F.; Kemit, L. F.; Nababan, E. B.; Sheta, O.

2018-03-01

Augmented Reality is a technique that can bring social story therapy into virtual world to increase intrinsic motivation of children with Autism Spectrum Disorder(ASD). By looking at the behaviour of ASD who will be difficult to get the focus, the lack of sensory and motor nerves in the use of loads on the hands or other organs will be very distressing children with ASD in doing the right activities, and interpret and understand the social situation in determining a response appropriately. Required method to be able to apply social story on therapy of children with ASD that is implemented with Augmented Reality. The output resulting from this method is 3D animation (three-dimensional animation) of social story by detecting marker located in special book and some simple game which done by using leap motion controller which is useful in reading hand movement in real-time.

Responses in large-scale structure

Energy Technology Data Exchange (ETDEWEB)

Barreira, Alexandre; Schmidt, Fabian, E-mail: barreira@MPA-Garching.MPG.DE, E-mail: fabians@MPA-Garching.MPG.DE [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85741 Garching (Germany)

2017-06-01

We introduce a rigorous definition of general power-spectrum responses as resummed vertices with two hard and n soft momenta in cosmological perturbation theory. These responses measure the impact of long-wavelength perturbations on the local small-scale power spectrum. The kinematic structure of the responses (i.e., their angular dependence) can be decomposed unambiguously through a ''bias'' expansion of the local power spectrum, with a fixed number of physical response coefficients , which are only a function of the hard wavenumber k . Further, the responses up to n -th order completely describe the ( n +2)-point function in the squeezed limit, i.e. with two hard and n soft modes, which one can use to derive the response coefficients. This generalizes previous results, which relate the angle-averaged squeezed limit to isotropic response coefficients. We derive the complete expression of first- and second-order responses at leading order in perturbation theory, and present extrapolations to nonlinear scales based on simulation measurements of the isotropic response coefficients. As an application, we use these results to predict the non-Gaussian part of the angle-averaged matter power spectrum covariance Cov{sup NG}{sub ℓ=0}( k {sub 1}, k {sub 2}), in the limit where one of the modes, say k {sub 2}, is much smaller than the other. Without any free parameters, our model results are in very good agreement with simulations for k {sub 2} ∼< 0.06 h Mpc{sup −1}, and for any k {sub 1} ∼> 2 k {sub 2}. The well-defined kinematic structure of the power spectrum response also permits a quick evaluation of the angular dependence of the covariance matrix. While we focus on the matter density field, the formalism presented here can be generalized to generic tracers such as galaxies.

Responses in large-scale structure

Science.gov (United States)

Barreira, Alexandre; Schmidt, Fabian

2017-06-01

We introduce a rigorous definition of general power-spectrum responses as resummed vertices with two hard and n soft momenta in cosmological perturbation theory. These responses measure the impact of long-wavelength perturbations on the local small-scale power spectrum. The kinematic structure of the responses (i.e., their angular dependence) can be decomposed unambiguously through a ``bias'' expansion of the local power spectrum, with a fixed number of physical response coefficients, which are only a function of the hard wavenumber k. Further, the responses up to n-th order completely describe the (n+2)-point function in the squeezed limit, i.e. with two hard and n soft modes, which one can use to derive the response coefficients. This generalizes previous results, which relate the angle-averaged squeezed limit to isotropic response coefficients. We derive the complete expression of first- and second-order responses at leading order in perturbation theory, and present extrapolations to nonlinear scales based on simulation measurements of the isotropic response coefficients. As an application, we use these results to predict the non-Gaussian part of the angle-averaged matter power spectrum covariance CovNGl=0(k1,k2), in the limit where one of the modes, say k2, is much smaller than the other. Without any free parameters, our model results are in very good agreement with simulations for k2 lesssim 0.06 h Mpc-1, and for any k1 gtrsim 2k2. The well-defined kinematic structure of the power spectrum response also permits a quick evaluation of the angular dependence of the covariance matrix. While we focus on the matter density field, the formalism presented here can be generalized to generic tracers such as galaxies.

Comparative study on γ energy spectrum denoise by fourier and wavelet transforms

International Nuclear Information System (INIS)

Shi Dongsheng; Di Yuming; Zhou Chunlin

2007-01-01

This paper introduces the basic principle of wavelet and Fourier transforms, applies wavelet transform method to denoise γ energy spectrum of 60 Co and compares it with Fourier transform method. The result of simulation with MATLAB software tool showed that as compared with traditional Fourier transform, wavelet transform has comparatively higher accuracy for γ energy spectrum denoising and is more feasible to γ energy spectrum denoising. (authors)

The exclusion-inclusion spectrum in state and community response to sex offenders in Anglo-American and European jurisdictions.

Science.gov (United States)

Petrunik, Michael; Deutschmann, Linda

2008-10-01

Continental European and Anglo-American jurisdictions differ with regard to criminal justice and community responses to sex offenders on an exclusion-inclusion spectrum ranging from community protection measures on one end to therapeutic programs in the middle and restorative justice measures on the other end. In the United States, populist pressure has resulted in a community protection approach exemplified by sex offender registration, community notification, and civil commitment of violent sexual predators. Although the United Kingdom and Canada have followed, albeit more cautiously, the American trend to adopt exclusionist community protection measures, these countries have significant community-based restorative justice initiatives, such as Circles of Support and Accountability. Although sex offender crises have recently occurred in continental Europe, a long-standing tradition of the medicalization of deviance, along with the existence of social structural buffers against the influence of victim-driven populist penal movements, has thus far limited the spread of formal community protection responses.

Feasibility and Efficacy of Prolonged Exposure for PTSD among Individuals with a Psychotic Spectrum Disorder

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Anouk L. Grubaugh

2017-06-01

Full Text Available Objective: Few empirical studies have examined the feasibility of trauma-focused treatment among individuals with schizophrenia. This lack of research is important given the substantial overlap of trauma exposure and subsequent PTSD with psychotic spectrum disorders, and the potential for PTSD to complicate the course and prognosis of schizophrenia and other variants of severe mental illness.Method: As part of a larger study, 14 veterans with a psychotic spectrum disorder were enrolled to receive prolonged exposure (PE for PTSD within a single arm open trial study design. Patient reactions and responses to PE were examined using feasibility indices such as attrition, survey reactions, and treatment expectancy; pre and post-changes in PTSD severity and diagnostic status; and thematic interviews conducted post-intervention.Results: Quantitative and qualitative data indicate that implementation of PE is feasible, subjectively well-tolerated, and may result in clinically significant reductions in PTSD symptoms in patients with psychotic spectrum disorders.Conclusion: Consistent with treatment outcome data in clinical populations with a broader range of severe mental illnesses, the current results support the use of PTSD exposure-based interventions, such as PE, for individuals with psychotic spectrum disorders.

[Investigation of multi-wavelength effect during the measurement of UV-enhanced film's emission spectrum].

Science.gov (United States)

Liu, Meng; Ni, Zheng-ji; Zhang, Da-wei; Huang, Yuan-shen; Zhuang, Song-lin

2009-09-01

The UV-responsive detector is a dual-use device for civilian and military after the laser and IR-responsive sensors. Typical image sensor coated with a layer of down-convert frequency thin film on it's photosurface to enhance UV response is the key technology of enhancing UV-response. The UV-enhanced thin film was made in the experimental laboratory using the Zn2SiO4:Mn phosphor by spin coating method. Two peaks at 520 and 560 nm respectively in the emission spectrum of the UV-enhanced film were found by SP1702 spectrograph when the excitation wavelength was 260 and 280 nm. The peaks were found in the process of experiment of measuring and counting the quantum efficiency of UV-enhanced thin film. But the light peaks at 520 and 560 nm are not the emission light peaks by the exciting light of 260 and 280 nm. The reason why the light at 520 and 560 nm is not the emission light was analyzed based on the measurement principle of grating spectrograph. The reasons for the multi-wavelength of light overlaps during the measurement of emission spectrum were also discussed. And the equipment used to separate the overlapped different wavelengths was designed, which will be used to resolve the problem of the overlap of multi-wavelength.

Implementation of 252Cf-source-driven power spectrum density measurement system

International Nuclear Information System (INIS)

Ren Yong; Wei Biao; Feng Peng; Li Jiansheng; Ye Cenming

2012-01-01

The principle of 252 Cf-source-driven power spectrum density measurement method is introduced. A measurement system and platform is realized accordingly, which is a combination of hardware and software, for measuring nuclear parameters. The detection method of neutron pulses based on an ultra-high-speed data acquisition card (three channels, 1 GHz sampling rate, 1 ns synchronization) is described, and the data processing process and the power spectrum density algorithm on PC are designed. This 252 Cf-source-driven power spectrum density measurement system can effectively obtain the nuclear tag parameters of nuclear random processes, such as correlation function and power spectrum density. (authors)

A calibration method for PLLs based on transient response

DEFF Research Database (Denmark)

Cassia, Marco; Shah, Peter Jivan; Bruun, Erik

2004-01-01

A novel method to calibrate the frequency response of a Phase-Locked Loop is presented. The method requires just an additional digital counter and an auxiliary Phase-Frequency Detector (PFD) to measure the natural frequency of the PLL. The measured value can be used to tune the PLL response...

Response-only method for damage detection of beam-like structures using high accuracy frequencies with auxiliary mass spatial probing

Science.gov (United States)

Zhong, Shuncong; Oyadiji, S. Olutunde; Ding, Kang

2008-04-01

This paper proposes a new approach based on auxiliary mass spatial probing using spectral centre correction method (SCCM), to provide a simple solution for damage detection by just using the response time history of beam-like structures. The natural frequencies of a damaged beam with a traversing auxiliary mass change due to change in the inertia of the beam as the auxiliary mass is traversed along the beam, as well as the point-to-point variations in the flexibility of the beam. Therefore the auxiliary mass can enhance the effects of the crack on the dynamics of the beam and, therefore, facilitate the identification and location of damage in the beam. That is, the auxiliary mass can be used to probe the dynamic characteristic of the beam by traversing the mass from one end of the beam to the other. However, it is impossible to obtain accurate modal frequencies by the direct operation of the fast Fourier transform (FFT) of the response data of the structure because the frequency spectrum can be only calculated from limited sampled time data which results in the well-known leakage effect. SCCM is identical to the energy centrobaric correction method (ECCM) which is a practical and effective method used in rotating mechanical fault diagnosis and which resolves the shortcoming of FFT and can provide high accuracy estimate of frequency, amplitude and phase. In the present work, the modal responses of damaged simply supported beams with auxiliary mass are computed using the finite element method (FEM). The graphical plots of the natural frequencies calculated by SCCM versus axial location of auxiliary mass are obtained. However, it is difficult to locate the crack directly from the curve of natural frequencies. A simple and fast method, the derivatives of natural frequency curve, is proposed in the paper which can provide crack information for damage detection of beam-like structures. The efficiency and practicability of the proposed method is illustrated via numerical

Study of spectral response of a neutron filter. Design of a method to adjust spectra

International Nuclear Information System (INIS)

Colomb-Dolci, F.

1999-02-01

The first part of this thesis describes an experimental method which intends to determine a neutron spectrum in the epithermal range [1 eV -10 keV]. Based on measurements of reaction rates provided by activation foils, it gives flux level in each energy range corresponding to each probe. This method can be used in any reactor location or in a neutron beam. It can determine scepter on eight energy groups, five groups in the epithermal range. The second part of this thesis presents a study of an epithermal neutron beam design, in the frame of Neutron Capture Therapy. A beam tube was specially built to test filters made up of different materials. Its geometry was designed to favour epithermal neutron crossing and to cut thermal and fast neutrons. A code scheme was validated to simulate the device response with a Monte Carlo code. Measurements were made at ISIS reactor and experimental spectra were compared to calculated ones. This validated code scheme was used to simulate different materials usable as shields in the tube. A study of these shields is presented at the end of this thesis. (author)

Analysis of biological spectrum of Divčibare flora

Directory of Open Access Journals (Sweden)

Popović Ivana

2006-01-01

Full Text Available One of the essential analyses which is performed during the floristic study of a region is the analysis of the biological spectrum. The analysis of the biological spectrum of the flora includes the determination of the type of life form for each taxon described in the flora of the study region. If it is considered that life form is a specific structural-functional response to the environmental effects and the result of the adaptation during the species evolution, it is clear that the basic characteristics of the site are more or less reflected in any life form. This fact is confirmed by the analysis of the biological spectrum of Divčibare flora. The study results are in correlation with the results of the analysis of the biological spectrum of the flora of Serbia and the Balkan Peninsula.

Cross-spectrum symbol synchronization

Science.gov (United States)

Mccallister, R. D.; Simon, M. K.

1981-01-01

A popular method of symbol synchronization exploits one aspect of generalized harmonic analysis, normally referred to as the cross-spectrum. Utilizing nonlinear techniques, the input symbol energy is effectively concentrated onto multiples of the symbol clock frequency, facilitating application of conventional phase lock synchronization techniques. A general treatment of the cross-spectrum technique is developed and shown to be applicable across a broad class of symbol modulation formats. An important specific symbol synchronization application is then treated, focusing the general development to provide both insight and quantitative measure of the performance impact associated with variation in these key synchronization parameters: symbol modulation format, symbol transition probability, symbol energy to noise density ratio, and symbol rate to filter bandwidth ratio.

Study on Stationarity of Random Load Spectrum Based on the Special Road

Science.gov (United States)

Yan, Huawen; Zhang, Weigong; Wang, Dong

2017-09-01

In the special road quality assessment method, there is a method using a wheel force sensor, the essence of this method is collecting the load spectrum of the car to reflect the quality of road. According to the definition of stochastic process, it is easy to find that the load spectrum is a stochastic process. However, the analysis method and application range of different random processes are very different, especially in engineering practice, which will directly affect the design and development of the experiment. Therefore, determining the type of a random process has important practical significance. Based on the analysis of the digital characteristics of road load spectrum, this paper determines that the road load spectrum in this experiment belongs to a stationary stochastic process, paving the way for the follow-up modeling and feature extraction of the special road.

Play-Based Interventions for Children and Adolescents with Autism Spectrum Disorders

Science.gov (United States)

Gallo-Lopez, Loretta, Ed.; Rubin, Lawrence C., Ed.

2012-01-01

"Play-Based Interventions for Children and Adolescents with Autism Spectrum Disorders" explores the most recognized, researched, and practical methods for using play therapy with the increasing number of children diagnosed with Autism Spectrum Disorders (ASDs), and shows clinicians how to integrate these methods into their practices. Using a…

Impulse response identification with deterministic inputs using non-parametric methods

International Nuclear Information System (INIS)

Bhargava, U.K.; Kashyap, R.L.; Goodman, D.M.

1985-01-01

This paper addresses the problem of impulse response identification using non-parametric methods. Although the techniques developed herein apply to the truncated, untruncated, and the circulant models, we focus on the truncated model which is useful in certain applications. Two methods of impulse response identification will be presented. The first is based on the minimization of the C/sub L/ Statistic, which is an estimate of the mean-square prediction error; the second is a Bayesian approach. For both of these methods, we consider the effects of using both the identity matrix and the Laplacian matrix as weights on the energy in the impulse response. In addition, we present a method for estimating the effective length of the impulse response. Estimating the length is particularly important in the truncated case. Finally, we develop a method for estimating the noise variance at the output. Often, prior information on the noise variance is not available, and a good estimate is crucial to the success of estimating the impulse response with a nonparametric technique

Psychotic-spectrum symptoms, cumulative adversity exposure and substance use among high-risk girls.

Science.gov (United States)

Lansing, Amy E; Plante, Wendy Y; Fennema-Notestine, Christine; Golshan, Shahrokh; Beck, Audrey N

2018-02-01

Psychotic-spectrum symptoms are linked to trauma, substance/alcohol use (SAU), criminality/violence and poor functional outcomes, supporting the need for early detection in vulnerable populations. To better understand high-risk girls' mental health, we assessed: (1) psychotic-spectrum symptoms; (2) cumulative trauma, adversity and loss exposures (C-TALE) and adversity-indicators (symptoms, maladaptive coping, stressor-reactivity); and SAU risk-factors; and (3) relationships among psychotic-spectrum symptoms, adversity-indicators and SAU risk-factors. We administered the Structured Clinical Interviews for Psychotic Spectrum, and Trauma and Loss Spectrum to 158 adolescent delinquent girls. Girls' psychotic-spectrum profiles were similar to previously reported adult psychotic patients and characterized by typical symptoms (hallucinations/delusions, reported largely SAU-independent), interpersonal sensitivity, schizoid traits and paranoia (over-interpretation, anger over-reactivity, hypervigilance). Auditory/visual hallucinations (55.7%), delusions (92.4%), ideas of reference (96.8%) and adversity (90.0% ≥10/24 C-TALE-types) were common. Mean loss (4) and trauma (8) onset-age occurred before SAU-onset (12). Significant positive correlations were found among psychotic-spectrum symptoms, stressor-reactivity, C-TALE, adversity-indicators; and number of SAU-types; and a negative correlation occurred between psychotic-spectrum symptoms and earlier alcohol use onset. After controlling for number of SAU-types, stressor-reactivity and adversity-related numbing individually had the largest associations with total psychotic-spectrum symptoms (b = 2.6-4.3). Girls averaged more than 4 maladaptive coping strategies (e.g., 24.8% attempted suicide) in response to adversity, amplifying potential health-disparities. No racial/ethnic differences emerged on psychotic-spectrum symptoms. This symptom constellation during adolescence likely interferes with social and academic

Quantitative Diagnosis of Rotor Vibration Fault Using Process Power Spectrum Entropy and Support Vector Machine Method

Directory of Open Access Journals (Sweden)

Cheng-Wei Fei

2014-01-01

Full Text Available To improve the diagnosis capacity of rotor vibration fault in stochastic process, an effective fault diagnosis method (named Process Power Spectrum Entropy (PPSE and Support Vector Machine (SVM (PPSE-SVM, for short method was proposed. The fault diagnosis model of PPSE-SVM was established by fusing PPSE method and SVM theory. Based on the simulation experiment of rotor vibration fault, process data for four typical vibration faults (rotor imbalance, shaft misalignment, rotor-stator rubbing, and pedestal looseness were collected under multipoint (multiple channels and multispeed. By using PPSE method, the PPSE values of these data were extracted as fault feature vectors to establish the SVM model of rotor vibration fault diagnosis. From rotor vibration fault diagnosis, the results demonstrate that the proposed method possesses high precision, good learning ability, good generalization ability, and strong fault-tolerant ability (robustness in four aspects of distinguishing fault types, fault severity, fault location, and noise immunity of rotor stochastic vibration. This paper presents a novel method (PPSE-SVM for rotor vibration fault diagnosis and real-time vibration monitoring. The presented effort is promising to improve the fault diagnosis precision of rotating machinery like gas turbine.

Generation of artificial time-histories, rich in all frequencies, from given response spectra

International Nuclear Information System (INIS)

Levy, S.; Wilkinson, J.P.D.

1975-01-01

In order to apply the time-history method of seismic analysis, it is often desirable to generate a suitable artificial time-history from a given response spectrum. The method described allows the generation of such a time-history that is also rich in all frequencies in the spectrum. This richness is achieved by choosing a large number of closely-spaced frequency points such that the adjacent frequencies have their half-power points overlap. The adjacent frequencies satisfy the condition that the frequency interval Δf near a given frequency f is such that (Δf)/f<2c/csub(c) where c is the damping of the system and csub(c) is the critical damping. In developing an artificial time-history, it is desirable to specify the envelope and duration of the record, very often in such a manner as to reproduce the envelope property of a specific earthquake record, and such an option is available in the method described. Examples are given of the development of typical artificial time-histories from earthquake design response spectra and from floor response spectra

Korean Culture and Autism Spectrum Disorders

Science.gov (United States)

Kang-Yi, Christina D.; Grinker, Roy R.; Mandell, David S.

2013-01-01

This paper reviews the literature on early child development among Koreans, with a focus on autism spectrum disorders (ASD). The literature review of 951 abstracts in English, 101 abstracts in Korean and 27 full articles published from 1994 to 2011 was performed to understand the presentation of and response to ASD in Korean culture. Based on…

Hermitian Mindlin Plate Wavelet Finite Element Method for Load Identification

Directory of Open Access Journals (Sweden)

Xiaofeng Xue

2016-01-01

Full Text Available A new Hermitian Mindlin plate wavelet element is proposed. The two-dimensional Hermitian cubic spline interpolation wavelet is substituted into finite element functions to construct frequency response function (FRF. It uses a system’s FRF and response spectrums to calculate load spectrums and then derives loads in the time domain via the inverse fast Fourier transform. By simulating different excitation cases, Hermitian cubic spline wavelets on the interval (HCSWI finite elements are used to reverse load identification in the Mindlin plate. The singular value decomposition (SVD method is adopted to solve the ill-posed inverse problem. Compared with ANSYS results, HCSWI Mindlin plate element can accurately identify the applied load. Numerical results show that the algorithm of HCSWI Mindlin plate element is effective. The accuracy of HCSWI can be verified by comparing the FRF of HCSWI and ANSYS elements with the experiment data. The experiment proves that the load identification of HCSWI Mindlin plate is effective and precise by using the FRF and response spectrums to calculate the loads.

A Prospective Study on the Clinical and Microbiological Spectrum of Endophthalmitis in a Specific Region in Denmark

DEFF Research Database (Denmark)

Solborg Bjerrum, Søren; Hamoudi, Hassan; Friis-Møller, Alice

2016-01-01

PURPOSE: To study the clinical and microbiological spectrum of endophthalmitis with emphasis on clinical features, visual outcomes and risks of surgical complications. METHODS: A prospective observational study was conducted between 2012 and 2013 in a specific region in Denmark. Patients were...... clinically examined before, during and after surgical intervention for endophthalmitis. RESULTS: Fifty eyes with endophthalmitis were included. Endophthalmitis after cataract surgery (post-cataract), anti-VEGF (vascular endothelial growth factor) intravitreal injections (post-injection) and cases...... of endogenous endophthalmitis were responsible for 40, 28 and 18% of all cases, respectively. There was no difference in the microbiological spectrum in post-cataract patients and post-injection patients, but patients with post-cataract endophthalmitis presented statistically significantly more frequently...

[Signal analysis and spectrum distortion correction for tunable diode laser absorption spectroscopy system].

Science.gov (United States)

Bao, Wei-Yi; Zhu, Yong; Chen, Jun; Chen, Jun-Qing; Liang, Bo

2011-04-01

In the present paper, the signal of a tunable diode laser absorption spectroscopy (TDLAS) trace gas sensing system, which has a wavelength modulation with a wide range of modulation amplitudes, is studied based on Fourier analysis method. Theory explanation of spectrum distortion induced by laser intensity amplitude modulation is given. In order to rectify the spectrum distortion, a method of synchronous amplitude modulation suppression by a variable optical attenuator is proposed. To validate the method, an experimental setup is designed. Absorption spectrum measurement experiments on CO2 gas were carried out. The results show that the residual laser intensity modulation amplitude of the experimental system is reduced to -0.1% of its original value and the spectrum distortion improvement is 92% with the synchronous amplitude modulation suppression. The modulation amplitude of laser intensity can be effectively reduced and the spectrum distortion can be well corrected by using the given correction method and system. By using a variable optical attenuator in the TDLAS (tunable diode laser absorption spectroscopy) system, the dynamic range requirements of photoelectric detector, digital to analog converter, filters and other aspects of the TDLAS system are reduced. This spectrum distortion correction method can be used for online trace gas analyzing in process industry.

Quantitative interpretation of nuclear logging data by adopting point-by-point spectrum striping deconvolution technology

International Nuclear Information System (INIS)

Tang Bin; Liu Ling; Zhou Shumin; Zhou Rongsheng

2006-01-01

The paper discusses the gamma-ray spectrum interpretation technology on nuclear logging. The principles of familiar quantitative interpretation methods, including the average content method and the traditional spectrum striping method, are introduced, and their limitation of determining the contents of radioactive elements on unsaturated ledges (where radioactive elements distribute unevenly) is presented. On the basis of the intensity gamma-logging quantitative interpretation technology by using the deconvolution method, a new quantitative interpretation method of separating radioactive elements is presented for interpreting the gamma spectrum logging. This is a point-by-point spectrum striping deconvolution technology which can give the logging data a quantitative interpretation. (authors)

Using Qualitative Methods to Guide Scale Development for Anxiety in Youth with Autism Spectrum Disorder

Science.gov (United States)

Bearss, Karen; Taylor, Christopher A.; Aman, Michael G.; Whittemore, Robin; Lecavalier, Luc; Miller, Judith; Pritchett, Jill; Green, Bryson; Scahill, Lawrence

2016-01-01

Anxiety is common in youth with autism spectrum disorder. Despite this common co-occurrence, studies targeting anxiety in this population are hindered by the under-developed state of measures in youth with autism spectrum disorder. Content validity (the extent to which an instrument measures the domain of interest) and an instrument's relevance to…

Conventional estimating method of earthquake response of mechanical appendage system

International Nuclear Information System (INIS)

Aoki, Shigeru; Suzuki, Kohei

1981-01-01

Generally, for the estimation of the earthquake response of appendage structure system installed in main structure system, the method of floor response analysis using the response spectra at the point of installing the appendage system has been used. On the other hand, the research on the estimation of the earthquake response of appendage system by the statistical procedure based on probability process theory has been reported. The development of a practical method for simply estimating the response is an important subject in aseismatic engineering. In this study, the method of estimating the earthquake response of appendage system in the general case that the natural frequencies of both structure systems were different was investigated. First, it was shown that floor response amplification factor was able to be estimated simply by giving the ratio of the natural frequencies of both structure systems, and its statistical property was clarified. Next, it was elucidated that the procedure of expressing acceleration, velocity and displacement responses with tri-axial response spectra simultaneously was able to be applied to the expression of FRAF. The applicability of this procedure to nonlinear system was examined. (Kako, I.)

Analysis of random response of structure with uncertain parameters. Combination of substructure synthesis method and hierarchy method

International Nuclear Information System (INIS)

Iwatsubo, Takuzo; Kawamura, Shozo; Mori, Hiroyuki.

1995-01-01

In this paper, the method to obtain the random response of a structure with uncertain parameters is proposed. The proposed method is a combination of the substructure synthesis method and the hierarchy method. The concept of the proposed method is that the hierarchy equation of each substructure is obtained using the hierarchy method, and the hierarchy equation of the overall structure is obtained using the substructure synthesis method. Using the proposed method, the reduced order hierarchy equation can be obtained without analyzing the original whole structure. After the calculation of the mean square value of response, the reliability analysis can be carried out based on the first passage problem and Poisson's excursion rate. As a numerical example of structure, a simple piping system is considered. The damping constant of the support is considered as the uncertainty parameter. Then the random response is calculated using the proposed method. As a result, the proposed method is useful to analyze the random response in terms of the accuracy, computer storage and calculation time. (author)

Reliability-based design optimization via high order response surface method

International Nuclear Information System (INIS)

Li, Hong Shuang

2013-01-01

To reduce the computational effort of reliability-based design optimization (RBDO), the response surface method (RSM) has been widely used to evaluate reliability constraints. We propose an efficient methodology for solving RBDO problems based on an improved high order response surface method (HORSM) that takes advantage of an efficient sampling method, Hermite polynomials and uncertainty contribution concept to construct a high order response surface function with cross terms for reliability analysis. The sampling method generates supporting points from Gauss-Hermite quadrature points, which can be used to approximate response surface function without cross terms, to identify the highest order of each random variable and to determine the significant variables connected with point estimate method. The cross terms between two significant random variables are added to the response surface function to improve the approximation accuracy. Integrating the nested strategy, the improved HORSM is explored in solving RBDO problems. Additionally, a sampling based reliability sensitivity analysis method is employed to reduce the computational effort further when design variables are distributional parameters of input random variables. The proposed methodology is applied on two test problems to validate its accuracy and efficiency. The proposed methodology is more efficient than first order reliability method based RBDO and Monte Carlo simulation based RBDO, and enables the use of RBDO as a practical design tool.

Method for quantifying the uncertainty with the extraction of the raw data of a gamma ray spectrum by deconvolution software

International Nuclear Information System (INIS)

Vigineix, Thomas; Guillot, Nicolas; Saurel, Nicolas

2013-06-01

Gamma ray spectrometry is a passive non destructive assay most commonly used to identify and quantify the radionuclides present in complex huge objects such as nuclear waste packages. The treatment of spectra from the measurement of nuclear waste is done in two steps: the first step is to extract the raw data from the spectra (energies and the net photoelectric absorption peaks area) and the second step is to determine the detection efficiency of the measuring scene. Commercial software use different methods to extract the raw data spectrum but none are optimal in the treatment of spectra containing actinides. Spectra should be handled individually and requires settings and an important feedback part from the operator, which prevents the automatic process of spectrum and increases the risk of human error. In this context the Nuclear Measurement and Valuation Laboratory (LMNE) in the Atomic Energy Commission Valduc (CEA Valduc) has developed a new methodology for quantifying the uncertainty associated with the extraction of the raw data over spectrum. This methodology was applied with raw data and commercial software that need configuration by the operator (GENIE2000, Interwinner...). This robust and fully automated methodology of uncertainties calculation is performed on the entire process of the software. The methodology ensures for all peaks processed by the deconvolution software an extraction of energy peaks closed to 2 channels and an extraction of net areas with an uncertainty less than 5 percents. The methodology was tested experimentally with actinides spectrum. (authors)

Derivation of muon range spectrum under rock from the recent primary spectrum

International Nuclear Information System (INIS)

Pal, P.; Bhattacharyya, D.P.

1985-01-01

The muon range spectra under Mont Blanc Tunnel and Kolar Gold Field rocks have been calculated from the recently measured primary cosmic ray spectrum. The scaling hypothesis of Feynman has been used for the calculation of pion and kaon spectra in the atmosphere. The meson atmospheric diffusion equation has been solved by following the method of Bugaev et al. The derived muon energy spectrum has been found to be in good agreement with the measured data of the Kiel, Durham, DEIS, and Moscow University groups. The calculated muon energy spectra at large polar angles have been compared with the different experimental results. The integral muon spectrum up to 20 TeV supports the MARS burst data favourably. Using the procedure of Kobayakawa, the muon energy loss in rock due to ionization, pair production, and bremsstrahlung and nuclear interactions from Bezrukov and Bugaev, we have constructed the range-energy relation in Mont Blanc and Kolar Gold Field rocks. The estimated range spectra have been corrected for range fluctuations and have been compared with the Mont Blanc Tunnel data of Castagnoli et al., Bergamasco et al., and Sheldon et al. and the Kolar Gold Field data compilation by Krishnaswamy et al

Was The Electromagnetic Spectrum A Blackbody Spectrum In The Early Universe?

OpenAIRE

Opher, Merav; Opher, Reuven

1997-01-01

It is assumed, in general, that the electromagnetic spectrum in the Primordial Universe was a blackbody spectrum in vacuum. We derive the electromagnetic spectrum, based on the Fluctuation-Dissipation Theorem that describes the electromagnetic fluctuations in a plasma. Our description includes thermal and collisional effects in a plasma. The electromagnetic spectrum obtained differs from the blackbody spectrum in vacuum at low frequencies. In particular, concentrating on the primordial nucleo...

The VEGA Assembly Spectrum Code

International Nuclear Information System (INIS)

Milosevic, M.

1997-01-01

The VEGA is assembly spectrum code, developed as a design tool for producing a few-group averaged cross section data for a wide range of reactor types including both thermal and fast reactors. It belongs to a class of codes, which may be characterized by the separate stages for micro group, spectrum and macro group assembly calculations. The theoretical foundation for the development of the VEGA code was integral transport theory in the first-flight collision probability formulation. Two versions of VEGA are now in use, VEGA-1 established on standard equivalence theory and VEGA-2 based on new subgroup method applicable for any geometry for which a flux solution is possible. This paper describes a features which are unique to the VEGA codes with concentration on the basic principles and algorithms used in the proposed subgroup method. Presented validation of this method, comprise the results for a homogenous uranium-plutonium mixture and a PWR cell containing a recycled uranium-plutonium oxide. Example application for a realistic fuel dissolver benchmark problem , which was extensive analyzed in the international calculations, is also included. (author)

A deconvolution method for deriving the transit time spectrum for ultrasound propagation through cancellous bone replica models.

Science.gov (United States)

Langton, Christian M; Wille, Marie-Luise; Flegg, Mark B

2014-04-01

The acceptance of broadband ultrasound attenuation for the assessment of osteoporosis suffers from a limited understanding of ultrasound wave propagation through cancellous bone. It has recently been proposed that the ultrasound wave propagation can be described by a concept of parallel sonic rays. This concept approximates the detected transmission signal to be the superposition of all sonic rays that travel directly from transmitting to receiving transducer. The transit time of each ray is defined by the proportion of bone and marrow propagated. An ultrasound transit time spectrum describes the proportion of sonic rays having a particular transit time, effectively describing lateral inhomogeneity of transit times over the surface of the receiving ultrasound transducer. The aim of this study was to provide a proof of concept that a transit time spectrum may be derived from digital deconvolution of input and output ultrasound signals. We have applied the active-set method deconvolution algorithm to determine the ultrasound transit time spectra in the three orthogonal directions of four cancellous bone replica samples and have compared experimental data with the prediction from the computer simulation. The agreement between experimental and predicted ultrasound transit time spectrum analyses derived from Bland-Altman analysis ranged from 92% to 99%, thereby supporting the concept of parallel sonic rays for ultrasound propagation in cancellous bone. In addition to further validation of the parallel sonic ray concept, this technique offers the opportunity to consider quantitative characterisation of the material and structural properties of cancellous bone, not previously available utilising ultrasound.

A Review on Spectrum Sensing for Cognitive Radio: Challenges and Solutions

Directory of Open Access Journals (Sweden)

Yonghong Zeng

2010-01-01

Full Text Available Cognitive radio is widely expected to be the next Big Bang in wireless communications. Spectrum sensing, that is, detecting the presence of the primary users in a licensed spectrum, is a fundamental problem for cognitive radio. As a result, spectrum sensing has reborn as a very active research area in recent years despite its long history. In this paper, spectrum sensing techniques from the optimal likelihood ratio test to energy detection, matched filtering detection, cyclostationary detection, eigenvalue-based sensing, joint space-time sensing, and robust sensing methods are reviewed. Cooperative spectrum sensing with multiple receivers is also discussed. Special attention is paid to sensing methods that need little prior information on the source signal and the propagation channel. Practical challenges such as noise power uncertainty are discussed and possible solutions are provided. Theoretical analysis on the test statistic distribution and threshold setting is also investigated.

Was The Electromagnetic Spectrum A Blackbody Spectrum In The Early Universe?

International Nuclear Information System (INIS)

Opher, M.; Opher, R.

1997-01-01

It is generally assumed that the electromagnetic spectrum in the primordial universe was a blackbody spectrum in vacuum. We derive the electromagnetic spectrum based on the fluctuation-dissipation theorem that describes the electromagnetic fluctuations in a plasma. Our description includes thermal and collisional effects in a plasma. The electromagnetic spectrum obtained differs from a blackbody spectrum in vacuum at low frequencies. In particular, concentrating on the primordial nucleosynthesis era, it has more energy than the blackbody spectrum for frequencies less than 3ω pe to 6ω pe , where ω pe is the electron plasma frequency. copyright 1997 The American Physical Society

Dynamic response of domes in CANDU 600 MWe containments

International Nuclear Information System (INIS)

Aziz, T.S.; Meng, V.; Alizadeh, A.

1981-01-01

CANDU reactors of the 600 MWe type are typically housed in a cylindrical prestressed concrete containment structure; rising from a flat slab and ending in a domed roof. The principal components of this structure are: (a) a circular base slab, (b) a vertical cylinder and (c) a spherical dome cap. A unique feature of a CANDU 600 MWe containment structure is the existence of an inner spherical concrete dome, located below the outer spherical dome, which serves as the bottom of a reservoir for the storage of 560,000 imperial gallons of douzing water. The thickness of the prestressed cylinder wall is approximately doubled between the two domes to create a ring beam. Inside the containment there exists an internal concrete structure which is independent of the containment structure except for support on the base slab. The containment boundary is a fully prestressed concrete structure. This paper deals with the seismic behaviour of the CANDU 600 MWe containment structure and the effect of its unique features; such as the lower dome and the douzing water on this behaviour. The objective of the study is to evaluate the interaction (coupling) effects between the different components of the structure. The approach taken is to study each component of the structure individually, then an assembly of the different components, and finally the total containment structure. This presentation is limited to the vertical response of the structure under a vertical earthquake only. Axisymmetric finite elements were used in all models. The vertical responses at selected points of the structure were obtained by the response spectrum method as well as the time-history method. It was observed that the response spectrum method over-estimates the vertical response of the domes and under-estimates the vertical responses of the ring girder and the containment cylinder compared to the time-history method. (orig./RW)

TESTBED IMPLEMENTATION OF MULTI DIMENSIONAL SPECTRUM SENSING SCHEMES FOR COGNITIVE RADIO

Directory of Open Access Journals (Sweden)

Deepa N Reddy

2016-06-01

Full Text Available Cognitive Radio (CR is a promising technology to exploit the underutilized spectrum. Spectrum sensing is one of the most important components for the establishment of cognitive radio system. Spectrum sensing allows the secondary users (SUs to detect the presence of the primary users (PUs. The aim of this work is to create a CR environment to study the spectrum sensing methods using Universal software radio Peripheral (USRP boards. In this paper a novel method of estimation of spectrum opportunities in multiple dimensions especially the space and the angle dimensions are carried out on USRP boards. This paper typically provides the experimental results carried out in an indoor wireless environment. To enhance the sensing performance the space dimension is firstly studied using spatial diversity of the cooperative SUs. Secondly the receiver diversity is analyzed using multiple antennas to enhance the error performance of the wireless system. The spectrum usage is also determined in the angle dimension by investigating the direction of the dominant signals using MUSIC algorithm.

Noninvasive hemoglobin measurement using dynamic spectrum

Science.gov (United States)

Yi, Xiaoqing; Li, Gang; Lin, Ling

2017-08-01

Spectroscopy methods for noninvasive hemoglobin (Hgb) measurement are interfered by individual difference and particular weak signal. In order to address these problems, we have put forward a series of improvement methods based on dynamic spectrum (DS), including instrument design, spectrum extraction algorithm, and modeling approach. The instrument adopts light sources composed of eight laser diodes with the wavelength range from 600 nm to 1100 nm and records photoplethysmography signals at eight wavelengths synchronously. In order to simplify the optical design, we modulate the light sources with orthogonal square waves and design the corresponding demodulation algorithm, instead of adopting a beam-splitting system. A newly designed algorithm named difference accumulation has been proved to be effective in improving the accuracy of dynamic spectrum extraction. 220 subjects are involved in the clinical experiment. An extreme learning machine calibration model between the DS data and the Hgb levels is established. Correlation coefficient and root-mean-square error of prediction sets are 0.8645 and 8.48 g/l, respectively. The results indicate that the Hgb level can be derived by this approach noninvasively with acceptable precision and accuracy. It is expected to achieve a clinic application in the future.

The Maximum Entropy Method for Optical Spectrum Analysis of Real-Time TDDFT

International Nuclear Information System (INIS)

Toogoshi, M; Kano, S S; Zempo, Y

2015-01-01

The maximum entropy method (MEM) is one of the key techniques for spectral analysis. The major feature is that spectra in the low frequency part can be described by the short time-series data. Thus, we applied MEM to analyse the spectrum from the time dependent dipole moment obtained from the time-dependent density functional theory (TDDFT) calculation in real time. It is intensively studied for computing optical properties. In the MEM analysis, however, the maximum lag of the autocorrelation is restricted by the total number of time-series data. We proposed that, as an improved MEM analysis, we use the concatenated data set made from the several-times repeated raw data. We have applied this technique to the spectral analysis of the TDDFT dipole moment of ethylene and oligo-fluorene with n = 8. As a result, the higher resolution can be obtained, which is closer to that of FT with practically time-evoluted data as the same total number of time steps. The efficiency and the characteristic feature of this technique are presented in this paper. (paper)

Cortisol responses on the dexamethasone suppression test among women with Bulimia-spectrum eating disorders: associations with clinical symptoms.

Science.gov (United States)

Bruce, Kenneth R; Steiger, Howard; Israël, Mimi; Groleau, Patricia; Ng Ying Kin, N M K; Ouellette, Anne-Sophie; Sycz, Lindsay; Badawi, Ghislaine

2012-08-07

Evidence associates Bulimia Nervosa (BN) with altered functioning of the hypothalamic-pituitary-adrenal (HPA) axis, but the clinical implications of such alterations need to be better understood. We contrasted cortisol responses to the dexamethasone suppression test (DST) in bulimic and non-eating disordered women and examined relationships among DST cortisol responses, eating symptoms and co-morbid disturbances. Sixty women with Bulimia Spectrum (BS) Disorders (either BN or normal weight Eating Disorder NOS with regular binge eating or purging) and 54 non-eating disordered women of similar age and body mass index participated in a 0.5 mg DST, and completed interviews and questionnaires assessing eating symptoms and co-morbid psychopathology. Compared with the normal-eater group, the BS women demonstrated significantly less DST suppression. Among BS women, DST non-suppression was associated with more severe depression, anxiety and eating preoccupations. Our findings show BS women to show less DST suppression compared to normal eater women, and results link extent of non-suppression, in BS individuals, to severity of depression, anxiety and eating preoccupations. Copyright © 2012 Elsevier Inc. All rights reserved.