the normalized correlation accounting for binaural detection across center frequency bernstein and trahiotis l r bernstein and c trahiotis j acoust soc am 100 1754 1763 1996 recently reported the results of experiments designed to determine the form of interaural correlation that accounts for listeners sensitivities to interaural disparities within high frequency stimuli overall those results demonstrated that listeners abilities to discriminate changes in the interaural correlation of the envelope from a base correlation of 1 0 were well accounted for by the use of the normalized correlation the purpose of this study was to determine how well the normalized correlation computed subsequent to half wave rectification and low pass filtering could account for binaural detection data at low intermediate and high frequencies respectively in a four interval two alternative task listeners detected which interval contained a tone between 500 hz and 2 khz added antiphasically to diotic 100 hz wide noise nos nonsignal intervals contained the tone added homophasically noso performance was measured for signal to noise ratios between 30 and 30 db results indicated that a low pass filter function based on physiological measures of synchrony in cochlear nerve fibers in conjunction with the assumption of half wave square law rectification accounted for typically 80 of the variance in the behavioral data

analytical expressions for the envelope correlation of certain narrow band stimuli analytical solutions are presented for the correlation between the envelopes of certain narrow band stimuli which are typically used in binaural research these stimuli are either the sum of an in phase masker and an out of phase signal or they are two partially correlated noises because an envelope has a nonzero mean the solutions differ depending on whether the envelope correlation is expressed as the normalized cross correlation or as the normalized cross covariance pearson product moment correlation the envelope correlation depends on the statistics of the masker and the signal whereas the waveform correlation depends on neither this influence only disappears for the normalized envelope cross correlation provided that the correlation is close to one in this case the normalized envelope cross correlation is equal to the square root of the waveform correlation the results for two partially correlated noise bands are also of relevance for experiments dealing with monaural envelope discrimination and comodulation masking release

the geometric interpretation of correspondence analysis abstract correspondence analysis is an exploratory multivariate technique that converts a data matrix into a particular type of graphical display in which the rows and columns are depicted as points the method has a long and varied history and has appeared in different forms in the psychometric and ecological literature among others in this article we review the geometry of correspondence analysis and its geometric interpretation we also discuss various extensions of correspondence analysis to multivariate categorical data multiple correspondence analysis and a variety of other data types

modified extended tanh function method and its applications to nonlinear equations new exact travelling wave solutions for the generalized shallow water wave equation the improved boussinesq equation and the coupled system for the approximate equations for water waves are found using a modified extended tanh function method the obtained results include rational periodic singular and solitary wave solutions

solving the breaking soliton equation by he s variational method he s variational method is applied to obtain the soliton solutions of the breaking soliton equation where the semi inverse method is applied to establish a needed variational functional

a new algorithm for automatic computation of solitary wave solutions to nonlinear partial differential equations based on the exp function method abstract a new algorithm and its maple implementation aefm are presented to find exact solitary wave solutions of nonlinear partial differential equations pdes in terms of the exp function method it turns out that the program can perform the exp function method entirely automatically and output directly solitary solutions to n 1 dimensional pdes furthermore the package allows users to find desirable solutions with different input parameters the effectiveness of the algorithm is illustrated by applying it to a variety of equations

interaural correlation discrimination ii relation to binaural unmasking many theoretical models of binaural interaction assume that sensitivity to interaural correlation underlies binaural unmasking this paper explores the extent to which sensitivity to changes in interaural correlation implied by results from binaural detection experiments are consistent with sensitivity to changes in interaural correlation measured directly in correlation discrimination experiments the vehicle for this exploration is a simplified model of the underlying processes assumed by many models of binaural unmasking for the detection of narrow band signals in the presence of broadband noise consideration is given to psychometric function slopes detection thresholds bandwidth effects duration effects level effects and interaural parameter effects although many of the results obtained from our analysis are consistent with the notion that the cue in binaural detection tasks is a change in interaural correlation some significant inconsistencies are noted

comment on on the extended applications of homogeneous balance method in this letter we show that all results presented in senthilvelan s paper can be actually obtained by a direct method

applications of a further extended tanh method by using a further extended tanh method chaos solitons fract 17 2003 669 and symbolic computation system maple we obtain abundant new explicit exact solutions of the 2 1 dimensional burgers equation and the 2 1 dimensional boussinesq equation the new solutions including soliton like solutions period form solutions and some other solutions

the exp function method and generalized solitary solutions the exp function method is applied to a system of nonlinear partial differential equations and generalized solitary solutions with free parameters are obtained the solution procedure is simple with the help of symbolic computation

mosaic displays for multi way contingency tables abstract mosaic displays represent the counts in a contingency table by tiles whose size is proportional to the cell count this graphical display for categorical data generalizes readily to multi way tables this article discusses extensions of the mosaic display to highlight patterns of deviations from various models for categorical data first we introduce the use of color and shading to represent sign and magnitude of standardized residuals from a specified model for unordered categorical variables we show how the perception of patterns of association can be enhanced by reordering the categories second we introduce sequential mosaics of marginal subtables together with sequential models for these tables for a class of sequential models of joint independence the individual mosaics provide a graphic representation of a partition of the overall likelihood ratio g2 for complete independence in the full table into portions attributable to hypotheses about the marginal subtables

general expa function method for nonlinear evolution equations abstract this work generalizes the exponential function method in considering an arbitrary base a as opposed to the conventional base e for the exponential function the combined kdv mkdv equation is considered to reveal the effectiveness and convenience of the proposed generalization the study highlights the power of the proposed method on constructing solutions expressed in terms of exponential hyperbolic periodic symmetrical fibonacci symmetrical lucas and k fibonacci functions some of the obtained solitary wave solutions are sketched graphically

generalized solitary and periodic wave solutions to a 2 1 dimensional zakharov kuznetsov equation abstract in this paper the exp function method is employed to the zakharov kuznetsov equation as a 2 1 dimensional model for nonlinear rossby waves the observation of solitary wave solutions and periodic wave solutions constructed from the exponential function solutions reveal that our approach is very effective and convenient the obtained results may be useful for better understanding the properties of two dimensional coherent structures such as atmospheric blocking events

on the similarity of two theories of comodulation masking release it is observed that two theories of comodulation masking release mr namely the envelope correlation theory and the equalization and cancellation theory are nearly the same

binaural detection as a function of interaural correlation and bandwidth of masking noise implications for estimates of spectral resolution detection thresholds were measured for an antiphasic s 500 hz tone masked by a binaural noise as a function of the bandwidth of the noise several values of interaural correlation of the masking noise were used ranging from 1 to 1 the bandwidth dependence of the thresholds showed a pattern consistent with a 100 hz wide critical band for most values of interaural correlation even for those values which resulted in a considerable binaural release of masking only when the interaural correlation of the masking noise was very close to or equal to unity was the bandwidth dependence of the thresholds in accord with an approximately 300 hz wide binaural critical band measured in previous studies our analysis of the data calls into question the commonly stated notion that binaural processing is characterized by a wider critical band than is monaural processing

interaural correlation discrimination i bandwidth and level dependence measurements of interaural cross correlation jnds from two reference correlations at several bandwidths were obtained for constant total power and constant spectral power gaussian noise at a reference correlation of 1 the results indicate that for bandwidths less than or equal to 115 hz the jnd remains at a constant value of approximately 0 004 and monotonically increases discrimination performance degrades to approximately 0 04 as bandwidth increases above 115 hz at a reference correlation of 0 the jnd decreases discrimination performance improves from approximately 0 7 to 0 35 as the bandwidth increases from 3 to 115 hz and remains at a constant value of approximately 0 35 for bandwidths greater than 115 hz a decrease in the spectral level causes an increase in the jnds at a reference correlation of 1 and no change in the jnds at a reference correlation of 0 of the three models tested none is able to completely describe all of the empirical results

analytical expressions for the envelope correlation of narrow band stimuli used in cmr and bmld research analytical solutions are presented for the correlation between the envelopes of certain narrow band stimuli that are typically used in experiments on binaural unmasking and on comodulation masking release cmr these stimuli consist of two maskers with identical envelopes and a signal that is added to one of the maskers if the two maskers have the same center frequency and are presented to the right and left ear the stimulus resembles a binaural mosm condition if the two maskers have different center frequencies we have a cmr condition with one flanking band the solutions for the envelope correlation differ depending on whether the envelope correlation is expressed as normalized cross correlation or as normalized cross covariance pearson product moment correlation the envelope correlation depends on the statistics of the masker and the signal whereas the waveform correlation depends on neither this influence only disappears for the normalized envelope cross correlation provided that the masker level is much higher than the signal level in this case the envelope cross correlation is approximately equal to the square root of the waveform correlation it is argued that the different properties of both types of envelope correlation are of relevance for cmr research

the painleve property for partial differential equations ii backlund transformation lax pairs and the schwarzian derivative in this paper we investigate the painleve property for partial differential equations by application to several well known partial differential equations burgers kdv mkdv bousinesq higher order kdv and kp equations it is shown that consideration of the singular manifold leads to a formulation of these equations in terms of the schwarzian derivative this formulation is invariant under the moebius group acting on dependent variables and is shown to obtain the appropriate lax pair linearization for the underlying nonlinear pde

measurements of the binaural temporal window using a detection task two experiments investigated the shape of the binaural temporal window using a detection task in experiment 1 a 10 ms tone burst was presented binaurally out of phase during a burst of white noise which changed from being interaurally uncorrelated to correlated and back to uncorrelated the tone occurred during the correlated portion of the noise in one interval of each 2i fc trial detection thresholds were recorded using a 2 down 1 up adaptive procedure thresholds were measured for different durations of correlated noise 0 960 ms frequencies of tone burst 125 250 500 and 1000 hz and levels of noise 20 30 40 and 50 db spl hz window shapes based on nine candidate functions were fitted to the data using the assumption that the binaural masking release was related to the overall interaural correlation of noise admitted by the window fitted windows included both a forward and a backward lobe gaussian functions tended to give closer fits than exponential and rounded exponential functions and simple functions gave more parsimonious fits that those which included dynamic range limiting terms using simple gaussian fits the shape of the window was largely independent of frequency and level and the windows for individual listeners had equivalent rectangular durations ranging from 55 to 188 ms the asymmetry was variable although forward lobes were generally shorter than backward lobes experiment 2 ruled out the possibility that the forward lobe might be an artefact caused by distraction of the listener when the interaural phase change in the noise closely followed the signal in this experiment the out of phase tone was presented during a burst of partially correlated noise which changed after a variable interval to a fully correlated noise thresholds for detecting the tone rose i e performance worsened as the interval was increased distraction would have produced the opposite effect

binaural processing model based on contralateral inhibition iii dependence on temporal parameters this paper and two accompanying papers breebaart et al j acoust soc am 110 1074 1088 2001 110 1089 1104 2001 describe a computational model for the signal processing of the binaural auditory system the model consists of several stages of monaural and binaural preprocessing combined with an optimal detector simulations of binaural masking experiments were performed as a function of temporal stimulus parameters and compared to psychophysical data adapted from literature for this purpose the model was used as an artificial observer in a three interval forced choice procedure all model parameters were kept constant for all simulations model predictions were obtained as a function of the interaural correlation of a masking noise and as a function of both masker and signal duration furthermore maskers with a time varying interaural correlation were used predictions were also obtained for stimuli with time varying interaural time or intensity differences finally binaural forward maskin

the influence of interaural stimulus uncertainty on binaural signal detection this paper investigated the influence of stimulus uncertainty in binaural detection experiments and the predictions of several binaural models for such conditions masked thresholds of a 500 hz sinusoid were measured in an n s condition for both running and frozen noise maskers using a three interval forced choice 3ifc procedure the nominal masker correlation varied between 0 64 and 1 and the bandwidth of the masker was either 10 100 or 1000 hz the running noise thresholds were expected to be higher than the frozen noise thresholds because of stimulus uncertainty in the running noise conditions for an interaural correlation close to 1 no difference between frozen noise and running noise thresholds was expected for all values of the masker bandwidth these expectations were supported by the experimental data for interaural correlations less than 1 0 substantial differences between frozen and running noise conditions were observed for bandwidths of 10 and 100 hz two additional conditions were tested to further investigate the influence of stimulus uncertainty in the first condition a different masker sample was chosen on each trial but the correlation of the masker was forced to a fixed value in the second condition one of two independent frozen noise maskers was randomly chosen on each trial results from these experiments emphasized the influence of stimulus uncertainty in binaural detection tasks if the degree of uncertainty in binaural cues was reduced thresholds decreased towards thresholds in the conditions without any stimulus uncertainty in the analysis of the data stimulus uncertainty was expressed in terms of three theories of binaural processing the interaural correlation the ec theory and a model based on the processing of interaural intensity differences iids and interaural time differences itds this analysis revealed that none of the theories tested could quantitatively account for the observed thresholds in addition it was found that in conditions with stimulus uncertainty predictions based on correlation differ from those based on the ec theory

correspondence analysis used complementary to loglinear analysis loglinear analysis and correspondence analysis provide us with two different methods for the decomposition of contingency tables in this paper we will show that there are cases in which these two techniques can be used complementary to each other more specifically we will show that often correspondence analysis can be viewed as providing a decomposition of the difference between two matrices each following a specific loglinear model therefore in these cases the correspondence analysis solution can be interpreted in terms of the difference between these loglinear models a generalization of correspondence analysis recently proposed by escofier will also be discussed with this decomposition which includes classical correspondence analysis as a special case it is possible to use correspondence analysis complementary to loglinear analysis in more instances than those described for classical correspondence analysis in this context correspondence analysis is used for the decomposition of the residuals of specific restricted loglinear models

application of g g expansion method to regularized long wave rlw equation in this paper the g g expansion method with the aid of maple is used to obtain a generalized soliton solution for the generalized regularized long wave rlw equation each of the obtained solutions namely hyperbolic function solutions and trigonometric function solutions contain an explicit linear function of the variables in the considered equation it is shown that the proposed method provides a powerful mathematical tool for solving nonlinear wave equations in mathematical physics and engineering problems

analytical solutions for nonlinear long short wave interaction systems with highly complex structure abstract in this paper we investigate and use the new modified exp expansion method mem we apply the new mem to nonlinear long short wave interaction systems nlswis among our findings are sets of solutions including but not limited to new hyperbolic complex and dark soliton solutions not only is mem shown to be highly adaptable for partial differential equations with strong nonlinearities but also it turns out to be highly efficient despite its ease

exp function method for traveling wave solutions of nonlinear evolution equations in this paper we apply the exp function method to construct generalized solitary and periodic solutions of nonlinear evolution equations the proposed technique is tested on the modified zakharov kuznetsov zk and zakharov kuznetsov modified equal width zk mew equations these equations play a very important role in mathematical physics and engineering sciences the suggested algorithm is quite efficient and is practically well suited for use in these problems numerical results clearly indicate the reliability and efficiency of the proposed exp function method

the travelling wave solutions for non linear initial value problems using the homotopy perturbation method in this article we have used the homotopy perturbation method hpm to find the travelling wave solutions for some non linear initial value problems in the mathematical physics these problems consist of the burgers fisher equation the kuramoto sivashinsky equation the coupled schordinger kdv equations and the long short wave resonance equations together with initial conditions the results of these problems reveal that the hpm is very powerful effective convenient and quite accurate to the systems of non linear equations it is predicted that this method can be found widely applicable in engineering and physics

interaural fluctuations and the detection of interaural incoherence iii narrowband experiments and binaural models in the first two articles of this series reproducible noises with a fixed value of interaural coherence 0 992 were used to study the human ability to detect interaural incoherence it was found that incoherence detection is strongly correlated with fluctuations in interaural differences especially for narrow noise bandwidths but it remained unclear what function of the fluctuations best agrees with detection data in the present article ten different binaural models were tested against detection data for 14 and 108 hz bandwidths these models included different types of binaural processing independent interaural phase difference interaural level difference lateral position and short term cross correlation several preprocessing transformations of the interaural differences were incorporated compression of binaural cues temporal averaging and envelope weighting for the 14 hz bandwidth data the most successful model postulated that incoherence is detected via fluctuations of interaural phase and interaural level processed by independent centers that model correlated with detectability at r 0 87 that model proved to be more successful than short term cross correlation models incorporating standard physiologically based model features r 0 78 for the 108 hz bandwidth data detection performance varied much less among different waveforms and the data were less able to distinguish between models

solitary solutions periodic solutions and compacton like solutions using the exp function method in this paper the exp function method is used for seeking solitary solutions periodic solutions and compacton like solutions of nonlinear differential equations the combined kdv mkdv equation and the liouville equation are chosen to illustrate the effectiveness and convenience of the proposed method

an exp function method for new n soliton solutions with arbitrary functions of a 2 1 dimensional vcbk system in this paper the exp function method is generalized to construct n soliton solutions of the 2 1 dimensional variable coefficient broer kaup vcbk system as a result new and more general 1 soliton 2 soliton and 3 soliton solutions with arbitrary functions are obtained from which the uniform formulae of n soliton solutions are derived based on one of the obtained 2 soliton solution the fission and fusion phenomena between the peakons and solitary waves are investigated it is shown that the exp function method may provide us with a straightforward effective and alternative mathematical tool for generating n soliton solutions of nonlinear evolution equations in mathematical physics

accounting for binaural detection as a function of masker interaural correlation effects of center frequency and bandwidth binaural detection was measured as a function of the center frequency bandwidth and interaural correlation of masking noise thresholds were obtained for 500 hz or 125 hz s tonal signals and for the latter stimuli noise or signal plus noise transposed to 4 khz a primary goal was assessment of the generality of van der heijden and trahiotis j acoust soc am 101 1019 1022 1997 hypothesis that thresholds could be accounted for by the additive masking effects of the underlying no and n components of a masker having an interaural correlation of results indicated that 1 the overall patterning of the data depended neither upon center frequency nor whether information was conveyed via the waveform or by its envelope 2 thresholds for transposed stimuli improved relative to their low frequency counterparts as bandwidth of the masker was increased 3 the additivity approach accounted well for the data across stimulus conditions but consistently overestimated mlds especially for narrowband maskers 4 a quantitative approach explicitly taking into account the distributions of time varying itd based lateral positions produced by masker alone and signal plus masker waveforms proved more successful albeit while employing a larger set of assumptions parameters and computational complexity

exact solutions to the double sinh gordon equation by the tanh method and a variable separated ode method new exact travelling wave solutions for the double sinh gordon equation and its generalized form are formally derived by using the tanh method and the variable separated ode method the painleve property v e u is employed to support the tanh method in deriving exact solutions the work emphasizes the power of the methods in providing distinct solutions of different physical structures

new generalized jacobi elliptic function rational expansion method in this work a new generalized jacobi elliptic function rational expansion method is based upon twenty four jacobi elliptic functions and eight double periodic weierstrass elliptic functions which solve the elliptic equation f 2 r p f 2 q f 4 is described as a consequence abundant new jacobi weierstrass double periodic elliptic functions solutions for 3 1 dimensional kadmtsev petviashvili kp equation are obtained by using this method we show that the new method can be also used to solve other nonlinear partial differential equations npdes in mathematical physics

the contribution of static and dynamically varying itds and iids to binaural detection this paper investigates the relative contribution of various interaural cues to binaural unmasking in conditions with an interaurally in phase masker and an out of phase signal mos pi by using a modified version of multiplied noise as the masker and a sinusoid as the signal conditions with only interaural intensity differences iids only interaural time differences itds or combinations of the two were realized in addition the experimental procedure allowed the presentation of specific combinations of static and dynamically varying interaural differences in these conditions with multiplied noise as masker the interaural differences have a bimodal distribution with a minimum at zero iid or itd additionally by using the sinusoid as masker and the multiplied noise as signal a unimodal distribution of the interaural differences was realized through this variation in the shape of the distributions the close correspondence between the change in the interaural cross correlation and the size of the interaural differences is no longer found in contrast to the situation for a gaussian noise masker domnitz and colburn j acoust soc am 59 598 601 1976 when analyzing the mean thresholds across subjects the experimental results could not be predicted from parameters of the distributions of the interaural differences the mean the standard deviation or the root mean square value a better description of the subjects performance was given by the change in the interaural correlation but this measure failed in conditions which produced a static interaural intensity difference the data could best be described by using the energy of the difference signal as the decision variable an approach similar to that of the equalization and cancellation model

a variational principle for coupled nonlinear schrodinger equations with variable coefficients and high nonlinearity via he s semi inverse method a variational principle is established for coupled nonlinear schrodinger equations with variable coefficients and high nonlinearity the result obtained includes the ones known from the open literature as special cases