certificateless threshold ring signature we propose a t out of n certificateless threshold ring signature cl trs scheme and prove its security under a new and stronger set of security models the models capture a new adversarial capability called user partial key replacement attack which has been considered practical and realistic but has never been formalized before the new scheme requires only a constant number of bilinear pairing operations for signature verification it also has a compact signature size which is linear to the number of non signers i e n t rather than that of actual signers we also propose a 1 out of n cl trs i e a certificateless ring signature scheme which has the most efficient verification among all the certificateless ring signature schemes currently known

semilinear copulas a family of copulas called semilinear is constructed starting with some assumptions about the linearity of the copulas along some segments of the unit square this family contains some other known families of copulas e g cuadras auge frechet and has a nice statistical interpretation several construction methods are provided especially concerning aggregation of semilinear copulas and a special form of ordinal sum construction is introduced some results about related families of quasi copulas and semicopulas are hence given

correlation dimension of electroglottographic data from healthy and pathologic subjects this paper considers the effects of nonstationarity noise and finite data sets on the estimation of the correlation dimension of time series data characterizing the vibratory behavior of the vocal folds the electroglottographic signal of sustained a phonations from 10 healthy subjects and 20 subjects with vocal fold pathologies were used to reconstruct the state space in successively higher embeddings using the method of lags the dimension values were calculated from the scaling region the level area of the slope plots which did not increase for higher embeddings reasonably defined scaling regions were found in all of the data from the healthy subjects and from five of the pathologic subjects with values saturating between the first and second embeddings the egg data from those five pathologic subjects were nearly periodic from the remaining 15 subjects the scaling regions were highly constricted with nonconstant slopes so that dimension values could not be confidently estimated the results suggest that the correlation dimension is a highly subjective measure which is not usefully applied to abnormal egg data it is recommended that if used correlation dimension statistics need to be presented cautiously and graphical presentation of the data should be included

comparison of nonlinear dynamic methods and perturbation methods for voice analysis nonlinear dynamic methods and perturbation methods are compared in terms of the effects of signal length sampling rate and noise results of theoretical and experimental studies quantitatively show that measurements representing frequency and amplitude perturbations are not applicable to chaotic signals because of difficulties in pitch tracking and sensitivity to initial state differences perturbation analyses are only reliable when applied to nearly periodic voice samples of sufficiently long signal lengths that were obtained at high sampling rates and low noise levels in contrast nonlinear dynamic methods such as correlation dimension allow the quantification of chaotic time series additionally the correlation dimension method presents a more stable analysis of nearly periodic voice samples for shorter signal lengths lower sampling rates and higher noise levels the correlation dimension method avoids some of the methodological issues associated with perturbation methods and may potentially improve the ability for real time analysis as well as reduce costs in experimental designs for objectively assessing voice disorders

a family of transformed copulas with a singular component abstract in this paper we present a family of bivariate copulas obtained by transforming a given copula function by means of two increasing functions named as transformed copula one distinctive characteristic of the transformed copula is its singular component along the main diagonal conditions guaranteeing the transformed function to be a copula function are provided and several classes of the transformed copulas are given the singular component along the main diagonal of the transformed copula is verified and the tail dependence coefficients of transformed copulas are obtained some properties of the transformed copula are discussed such as the total positivity of order 2 and the concordance order finally conditions for the proposed transformation being invariant are given sufficient conditions guaranteeing that the iterative transformation is a copula function are provided and the convergence of the iterative transformation is proved under some conditions

transitivity bounds in additive fuzzy preference structures transitivity plays a crucial role in preference modeling and related fields in this paper we discuss this property in the general context of additive fuzzy preference structures of particular interest is the decomposition of a large preference relation r in its symmetric part i indifference relation and its asymmetric part p strict preference relation by means of a so called indifference generator i given the type of transitivity of a large preference relation r w r t a conjunctor and a generator we establish basic lower bounds and general upper bounds on the transitivity of p and i these bounds are due to the careful design of generic counterexamples moreover we identify the situations in which these bounds are effectively reached thereby establishing connections with interesting properties such as dominance bisymmetry the 1 lipschitz property and rotation invariance

the triple rotation method for constructing t norms given an involutive negator n and a left continuous t norm t that either has no zero divisors or is rotation invariant we build a rotation invariant t norm from a rescaled version of t and its left right and front rotation depending on the involutive negator n and the set of zero divisors of t some reshaping of the rescaled version of t may occur during the rotation process the rescaled version of t itself can be understood as the b zoom of the newly constructed rotation invariant t norm with b the unique fixpoint of n starting with a rotation invariant t norm t there is however one important restriction the triple rotation method based on the involutive negator n will yield a t norm if and only if the companion q of t is commutative on 0 1 2 when q is not commutative on 0 1 2 there even does not exist a rotation invariant t norm with b zoom equal to t

a construction method of semicopulas from fuzzy negations in this paper a method of defining commutative semicopulas from fuzzy negations is introduced some properties are investigated that lead to understand these semicopulas as non associative generalizations of the lukasiewicz t norm in particular it is proved that some well known examples of copulas and t norms can be obtained by this method moreover any commutative semicopula constructed by this method can be always obtained from a negation n which is symmetric with respect to the diagonal then those symmetric fuzzy negations n for which the corresponding semicopula is a copula are characterized also several examples of symmetric negations n are given such that the corresponding semicopula is a t norm

group signatures with controllable linkability for dynamic membership in this paper we present a novel group signature scheme for dynamic membership which enables fine grained control over the release of user information this scheme could be widely used for various anonymity based applications such as privacy preserving data mining and customized anonymous authentication owing to a useful property called controllable linkability a valid signer is able to create signatures that hide his or her identity as normal group signatures but can be anonymously linked regardless of changes to the membership status of the signer and without exposure of the history of the joining and revocation from signatures only linkage information can be disclosed with a special linking key using this controllable linkability and the controllable anonymity of a group signature anonymity may be flexibly or elaborately controlled according to a desired level to begin construction of our scheme we first introduce the decision linear combination dlc assumption in a so called gap diffie hellman group where the ddh problem is tractable but the cdh problem is hard and we prove that this assumption can be guaranteed in generic bilinear groups to identify security requirements more precisely we formally present definitions of anonymity traceability non frameabilty and linkability we then prove that our scheme achieves all these security properties in the random oracle model our scheme supporting controllable linkability yields a short signature that is only 33 3 longer than the best known normal group signature furthermore we show that our scheme is comparable to the group signature scheme in terms of the amount of computation for basic operations such as signing verification and the key update caused by revocation finally using the linkability for dynamic membership computation overhead in opening signer s identity can be significantly reduced or minimized

ortholinear and paralinear semi copulas abstract a new method to construct semi copulas is introduced these semi copulas are called ortholinear resp paralinear semi copulas and their construction is based on linear interpolation on segments that are perpendicular resp parallel to the diagonal of the unit square the classes of ortholinear and paralinear quasi copulas are characterized as well

a frequentist view on cycle transitivity of reciprocal relations we establish a connection between two transitivity frameworks the transitivity of fuzzy relations based on a commutative quasi copula and the cycle transitivity of reciprocal relations w r t the dual quasi copula as an upper bound function loosely speaking it turns out that the latter can be characterized by imposing a lower bound on the relative frequency with which the former is fulfilled when applied to reciprocal relations we provide two compelling cases the 4 6 theorem expressing that the winning probability relation of a set of independent random variables is at least 66 66 product transitive and the 5 6 theorem expressing that the mutual rank probability relation associated with a given poset is at least 83 33 product transitive moreover these lower bounds turn out be rather conservative illustrating that from a frequentist point of view transitivity is abundant

directional dependence of random vectors in this paper we define and study several properties of the concept of multivariate directional dependence and study the new concept in terms of copulas and provide new measures of multivariate association based on directional dependence finally we show the relationships of directional dependence with other dependence concepts such as association and conditional dependence

copulas with given track and opposite track sections solution to a problem on diagonals abstract in this note we provide conditions for the existence of a copula with given track and opposite track sections generalizing conditions for the existence of copulas with given diagonal and opposite diagonal sections in de amo et al 2016 3 we also use this construction to characterize a class of copulas with a fixed diagonal section providing as a consequence a solution to the problem 2 4 posed by c sempi in mesiar and sarkoci 2010 16

on linear and quadratic constructions of aggregation functions abstract in the paper we introduce and discuss linear and quadratic constructions of aggregation functions based on an a priori given aggregation function we focus our attention on linear and quadratic constructions transforming any aggregation function from the considered class of aggregation functions into a new aggregation function belonging to the same class we study quadratic constructions of distinguished classes of aggregation functions with neutral element 0 1 in particular semi copulas quasi copulas copulas triangular norms and their duals in all cases the final results fully characterize quadratic functions which are universal for quadratic constructions of aggregation functions of the considered type

nonlinear analysis of irregular animal vocalizations animal vocalizations range from almost periodic vocal fold vibration to completely atonal turbulent noise between these two extremes a variety of nonlinear dynamics such as limit cycles subharmonics biphonation and chaotic episodes have been recently observed these observations imply possible functional roles of nonlinear dynamics in animal acoustic communication nonlinear dynamics may also provide insight into the degree to which detailed features of vocalizations are under close neural control as opposed to more directly reflecting biomechanical properties of the vibrating vocal folds themselves so far nonlinear dynamical structures of animal voices have been mainly studied with spectrograms in this study the deterministic versus stochastic dvs prediction technique was used to quantify the amount of nonlinearity in three animal vocalizations macaque screams piglet screams and dog barks results showed that in vocalizations with pronounced harmonic components adult macaque screams certain piglet screams and dog barks deterministic nonlinear prediction was clearly more powerful than stochastic linear prediction the difference termed low dimensional nonlinearity measure lnm indicates the presence of a low dimensional attractor in highly irregular signals such as juvenile macaque screams piglet screams and some dog barks the detectable amount of nonlinearity was comparatively small analyzing 120 samples of dog barks it was further shown that the harmonic to noise ratio hnr was positively correlated with lnm it is concluded that nonlinear analysis is primarily useful in animal vocalizations with strong harmonic components including subharmonics and biphonation or low dimensional chaos

surrogate analysis for detecting nonlinear dynamics in normal vowels normal vowels are known to have irregularities in the pitch to pitch variation which is quite important for speech signals to be perceived as natural human sound such pitch to pitch variation of vowels is studied in the light of nonlinear dynamics for the analysis five normal vowels recorded from three male and two female subjects are exploited where the vowel signals are shown to have normal levels of the pitch to pitch variation first by the false nearest neighbor analysis nonlinear dynamics of the vowels are shown to be well analyzed by using a relatively low dimensional reconstructing dimension of 4 d 7 then we further studied nonlinear dynamics of the vowels by spike and wave surrogate analysis the results imply that there exists nonlinear dynamical correlation between one pitch waveform pattern to another in the vowel signals on the basis of the analysis results applicability of the nonlinear prediction technique to vowel synthesis is discussed

on an idempotent transformation of aggregation functions and its application on absolutely continuous archimedean copulas in this paper we isolate an interesting transformation of binary aggregation functions from a result on the propagation of transitivity in additive preference structures this transformation is based on a projection technique and results in a smaller or equal binary aggregation function the transformation is idempotent and acts internally on the classes of conjunctors semi copulas and quasi copulas hence also copulas are transformed into quasi copulas but in general not into copulas remarkably the frank copulas are mapped to new copulas

semiquadratic copulas based on horizontal and vertical interpolation we introduce several families of semiquadratic copulas i e copulas that are quadratic in any point of the unit square in at least one coordinate of which the diagonal and or opposite diagonal sections are given functions these copulas are constructed by quadratic interpolation on segments connecting the diagonal opposite diagonal and sides of the unit square all interpolations are therefore performed horizontally or vertically for each family we provide the necessary and sufficient conditions on the given diagonal and or opposite diagonal functions and two auxiliary real functions to obtain a copula that has these diagonal and or opposite diagonal functions as diagonal and or opposite diagonal sections just as the product copula is a central member of all families of semilinear copulas based on horizontal and vertical interpolation it turns out that the farlie gumbel morgenstern family of copulas is included in all families of semiquadratic copulas introduced and characterized here

conic aggregation functions inspired by the notion of conic t norms we introduce conic aggregation functions such aggregation functions are completely characterized by their zero set special classes of binary conic aggregation functions such as conic quasi copulas and conic copulas are considered we provide the necessary and sufficient conditions on the boundary curve of the zero set of a conic aggregation function to obtain a conic quasi copula and conclude that the class of conic copulas is a proper subclass of the class of conic quasi copulas moreover we characterize the class of singular conic copulas we investigate some aggregations of conic quasi copulas some examples are also provided

access control in user hierarchy based on elliptic curve cryptosystem this work proposes a novel key management method based on elliptic curve cryptosystem and one way hash function to solve dynamic access problems in a user hierarchy the proposed scheme attempts to derive the secret key of successors efficiently and non redundantly it includes functions such as insertion and removal of classes updating of their relationships and changing of secret keys the method utilizes a central authority which enables a user to change the secret key at will conveniently since the proposed method uses the elliptic curve cryptosystem which has a low computational cost and small key size its performance in terms of both security and efficiency is quite commendable therefore it can be anticipated that its use will be extended to wireless communication in the future

rotation invariant t norms the rotation invariance property revisited focusing on conjunctive left continuous increasing 0 1 2 0 1 functions t we redefine the rotation invariance property in terms of contour lines under the assumption of the existence of a neutral element email protected 0 1 this rotation invariance property requires some partial commutativity and associativity the functions that are rotation invariant w r t all of their contour lines are characterized

fundamental limitations for estimating dimensions and lyapunov exponents in dynamical systems we show that values of the correlation dimension estimated over a decade from the grassberger procaccia algorithm cannot exceed the value 2 log10n if n is the number of points in the time series when this bound is saturated it is thus not legitimate to conclude that low dimensional dynamics is present the estimation of lyapunov exponents is also discussed

zero linear copulas abstract we introduce a new method for constructing copulas c a special type of aggregation functions based on the idea that c u v 0 if u g v for any continuous and decreasing function g 0 1 0 1 such that g 1 0 and c is linear if u g v 1 we also study the relationship between these copulas and other known families of copulas we provide some salient properties and measure the dependence and asymmetry in this class of copulas

copulas diagonals and tail dependence we present some known and novel aspects about bivariate copulas with prescribed diagonal section by highlighting their use in the description of the tail dependence moreover we present the tail concentration function which depends on the diagonal section of a copula as a tool to give a description of tail dependence at finite scale the tail concentration function is hence used to introduce a graphical tool that can help to distinguish different families of copulas in the copula test space moreover it serves as a basis to determine the grouping structure of different financial time series by taking into account their pairwise tail behavior

a new ring signature scheme with signer admission property in this paper we introduce an extended ring signature scheme in which the actual signer has the ability to admit to having signed a document at his will generally speaking this scheme can be considered as an extension and improvement of the ring signature suggested by rivest et al in 2001 the proposed scheme is called signer admission ring signature which combines the idea of the designated confirmer signatures proposed by chaum in 1994 and the designated verifier proofs proposed by jakobsson et al in 1996 this paper presents a scenario explaining why the signer admission property is valuable in real life applications an actual signer may possibly want to expose himself if in doing so he will acquire an enormous benefit here we propose a generic construction of the signer admission ring signature as well as a demonstration modified from rivest et al s scheme to achieve signer admission

zero sets of copulas abstract we study conditions on sets in order to be zero sets of semi copulas quasi copulas and with special attention of copulas we find necessary and sufficient conditions for characterizing the zero sets of absolutely continuous copulas and copulas whose support coincides with the closure of the complementary of the zero set moreover we study several topological properties and the lattice theoretic structure and characterize the zero sets of the class of archimedean copulas

time selective convertible undeniable signatures with short conversion receipts undeniable signatures were introduced in 1989 by chaum and van antwerpen to limit the self authenticating property of digital signatures an extended concept the convertible undeniable signatures proposed by boyar chaum damgard and pedersen in 1991 allows the signer to convert undeniable signatures to ordinary digital signatures in this article we present a new efficient convertible undeniable signature scheme based on bilinear maps its unforgeability is tightly related in the random oracle model to the computational diffie hellman problem and its anonymity to a non standard decisional assumption the advantages of our scheme are the short length of the signatures the low computational cost of the signature and the receipt generation moreover a variant of our scheme permits the signer to universally convert signatures pertaining only to a specific time period we formalize this new notion as the time selective conversion we also improve our original scheme from ct rsa 05 by reducing the length of the generated receipts their size is now logarithmic in the number of time periods

modeling of chaotic vibrations in symmetric vocal folds the chaos mechanism of above range phonation was examined in symmetrically modeled vocal folds by using the traditional two mass model assumption the poincare map technique was used to display chaotic attractors this method provided an effective description of irregular vocal fold movements the power spectrum lyapunov exponent and kaplan yorke dimension were employed to describe chaotic vibrations in the vocal fold model these nonlinear dynamic analyses suggested that for the positive lyapunov exponent chaotic attractors contribute to irregular vocal fold vibrations descriptions of complicated irregular vibrations of the vocal fold yielded evidence of chaos to investigate the effects of independent parameters such as subglottal pressure coupling stiffness and phonation neutral area bifurcation diagrams based on the poincare map were discussed the results confirmed that the dynamics of the two mass model was strongly influenced by independent parameters nonlinear dynamic methods were expecte

rotation invariant t norms where triple rotation and rotation annihilation meet generalizing the notion of a zoom of a t norm not only allows to extend the triple rotation method and its corresponding decomposition but also allows to describe the interface between the triple rotation method and the rotation annihilation method an alternative view on the partition behind the rotation annihilation method is required to make both methods compatible besides zooms we also use contour lines and the companion of a t norm to concisely formulate the results

the distribution of the probability mass of biconic copulas we study the probability mass distribution of biconic copulas provide a counterexample to a result given in jwaid et al 2012 29 concerning a characterization of singular biconic copulas and provide a new one

measurement of the lyapunov spectrum from a chaotic time series the exponential divergence or convergence of nearby trajectories lyapunov exponents is conceptually the most basic indicator of deterministic chaos we propose a new method to determine the spectrum of several lyapunov exponents including positive zero and even negative ones from the observed time series of a single variable we have applied the method to various known model systems and also to the rayleigh b enard experiment and have elucidated the dependence of the lyapunov exponents on the rayleigh number

a nonlinear dynamical systems analysis of fricative consonants acoustic waveforms of the strident fricatives s z sh and yog spoken by two native american english speakers are analyzed using modern chaotic analysis techniques fricative data are extracted from both intervocalic and sustained utterances for comparison acoustic waveforms of the vowels a i and u are also analyzed for 44 of the unvoiced fricative tokens in vcv contexts and 59 of the sustained voiced fricatives indications of low dimensional dynamics could be found with the given limitations of stationarity the low dimensional chaotic behavior is exhibited by a correlation dimension d2 ranging between 3 and 7 2 and by positive maximum lyapunov exponents les for the remaining fricatives results suggest that the dimensional complexity therein is greater than the maximum d2 value that could be reliably estimated from the available data about 7 8 for the intervocalic cases and 9 for the sustained cases intervocalic voiced fricatives are excluded from the analysis due to stat

an efficient key assignment scheme for access control in a large leaf class hierarchy the employees of an organization are usually divided into different security classes to authorize the information retrieval and the number of leaf classes is substantially larger than the number of non leaf classes additionally the alternations in leaf classes are more frequent than in non leaf classes we proposed a new key assignment scheme for controlling the access right in a large poset partially ordered set hierarchy to reduce the required computation for key generation and derivation with the storage amount of data decreased

the dimension of chaotic attractors dimension is perhaps the most basic property of an attractor in this paper we discuss a variety of different definitions of dimension compute their values for a typical example and review previous work on the dimension of chaotic attractors the relevant definitions of dimension are of two general types those that depend only on metric properties and those that depend on the frequency with which a typical trajectory visits different regions of the attractor both our example and the previous work that we review support the conclusion that all of the frequency dependent dimensions take on the same value which we call the dimension of the natural measure and all of the metric dimensions take on a common value which we call the fractal dimension furthermore the dimension of the natural measure is typically equal to the lyapunov dimension which is defined in terms of lyapunov numbers and thus is usually far easier to calculate than any other definition because it is computable and more physically relevant we feel that the dimension of the natural measure is more important than the fractal dimension

on a new construction of 1 lipschitz aggregation functions quasi copulas and copulas a new method of constructing 1 lipschitz aggregation functions is proposed and studied as a by product a new method of constructing quasi copulas from a given quasi copula c is obtained newly constructed copulas are negative quadrant dependent for any original copula c the only invariant copula under this construction is the frechet hoffding lower bound w the method preserves several important properties of copulas such as modularity absolute continuity or symmetry and commutes with some other constructions e g the construction of survival copulas

a secure effective key management scheme for dynamic access control in a large leaf class hierarchy lo et al 2011 proposed an efficient key assignment scheme for access control in a large leaf class hierarchy where the alternations in leaf classes are more frequent than in non leaf classes in the hierarchy their scheme is based on the public key cryptosystem and hash function where operations like modular exponentiations are very much costly compared to symmetric key encryptions and decryptions and hash computations their scheme performs better than the previously proposed schemes however in this paper we show that lo et al s scheme fails to preserve the forward security property where a security class c x can also derive the secret keys of its successor classes c j s even after deleting the security class c x from the hierarchy we aim to propose a new key management scheme for dynamic access control in a large leaf class hierarchy which makes use of symmetric key cryptosystem and one way hash function we show that our scheme requires significantly less storage and computational overheads as compared to lo et al s scheme and other related schemes through the informal and formal security analysis we further show that our scheme is secure against all possible attacks including the forward security in addition our scheme supports efficiently dynamic access control problems compared to lo et al s scheme and other related schemes thus higher security along with low storage and computational costs make our scheme more suitable for practical applications compared to other schemes

certificateless undeniable signatures from bilinear maps certificateless public key cryptosystem avoids the inherent key escrow problem in identity based public key cryptosystem and does not need expensive certificates in the public key infrastructure this cryptographic primitive has received a significant attention since it was introduced and lots of certificateless schemes have been proposed in the past years in this paper we propose an certificateless undeniable signature scheme based on bilinear maps to formally analyze the security of the proposed scheme we extend security notions of undeniable signatures in the traditional public key infrastructure to the certificateless setting under the formally defined security models we prove that our proposed scheme satisfies all the security properties under certain standard assumptions in the random oracle model compared with existed certificateless undeniable signatures the sign algorithm of our scheme is more efficient the weakness is that the unforgeability of our scheme is proved in a weak model

the distribution of the probability mass of conic copulas in this note we study the probability mass distribution of conic copulas provide counterexamples to a result given in jwaid et al 21 concerning a characterization of singular conic copulas and provide a new one

exchangeable copulas this paper focuses on exchangeable copulas some necessary and sufficient conditions are provided together with a characterization result in differential form a very flexible model capable to generate a wide range of exchangeable copulas is presented

an attractor in a solar time series a time series analysis of observed solar radio pulsations suggests that there must be a low dimensional attractor the power spectrum cannot be interpreted as a superposition of periodic components estimates of the maximum lyapunov exponent and of the kolmogorov entropy give some indications for a deterministic chaos in order to study the limitations inherent in small data samples we include data from the lorenz model and an artificial noise record consequences for the physical modelling of the pulsation event are discussed

bell type inequalities for quasi copulas we present all bell type inequalities regarding at most four random events of which not more than two are intersected at the same time reformulating these inequalities in the context of fuzzy probability calculus leads to related inequalities on commutative conjunctors we prove that some of these inequalities hold for quasi copulas or copulas additionally for the important parametric family of frank t norms which are also copulas we identify for each of the inequalities the parameter values for which it is fulfilled thereby completing the results of pykacz and d hooghe

phase modulated resonances modeled as self similar processes with application to turbulent sounds in this paper we propose a nonlinear stochastic model for time varying resonances where the instantaneous phase and frequency of a sinusoidal oscillation is allowed to vary proportionally to an spl alpha stable self similar stochastic processes the main motivation of our work stems from previous experimental and theoretical evidence that speech resonances in fricative sounds can be modeled phenomenologically as am fm signals with randomly varying instantaneous frequencies and that several signal classes related to turbulent phenomena are self similar 1 f processes our general approach is to model the instantaneous phase of an am fm resonance as a self similar spl alpha stable process as a special case this random phase model includes the class of random fractal signals known as fractional brownian motion we theoretically explore this random modulation model and analytically derive its autocorrelation and power spectrum we also propose an algorithm to fit this model to arbitrary resonances with random phase modulation further we apply the above ideas to real speech data and demonstrate that this model is suitable for resonances of fricative sounds

aggregation functions construction methods conjunctive disjunctive and mixed classes in this second part of our state of the art overview on aggregation theory based again on our recent monograph on aggregation functions we focus on several construction methods for aggregation functions and on special classes of aggregation functions covering the well known conjunctive disjunctive and mixed aggregation functions some fields of applications are included

global and local dimensions of vocal dynamics the global embedding dimension de and the local dynamical dimension dl are calculated from the microphone and electroglottographic egg signals elicited from five healthy subjects and seven dysphonic subjects with laryngeal pathology during phonation of sustained a the data from each pathologic subject contain at least one bifurcation and are divided into periodic and irregular segments for analysis the de values from both the microphone and egg signals elicited from the healthy subjects indicate that a relatively small coordinate space can be used to reconstruct the attractor with little residual noise consistent across all healthy subjects three dominant degrees of freedom dl are found to govern local dynamics of the trajectories on the attractor from the pathologic subjects many of the de values suggest the presence of a high dimensional component in the signals however the noise does not completely obscure the deterministic dynamics of the source signal or prevent extraction of an optimal global embedding dimension the data do not reveal consistent differences in degrees of freedom between healthy and pathologic phonation or between different modes of pathologic phonation however the dl values suggest that the pathologic vocal fold vibration of these subjects even highly irregular vibration is governed locally by a low number of dominant degrees of freedom sometimes no greater than those calculated from the signals of healthy subjects only in the cases of severe breathiness are the microphone and egg signals sufficiently contaminated by noise to obscure any deterministic component

aggregation based extensions of fuzzy measures we present a method extending fuzzy measures on n 1 n represented as boolean utility functions to n ary aggregation functions utility functions by means of a suitable n ary aggregation function and the mobius transform of the considered fuzzy measure the method generalizes the well known lovasz and owen extensions of nondecreasing pseudo boolean functions linked to fuzzy measures all n ary aggregation functions suitable for the proposed construction are completely characterized including among others all n ary copulas associative extended aggregation functions applicable in the case of an arbitrary arity are also completely characterized

concurrent signature without random oracles a concurrent signature provides an efficient way to exchange digital signatures between parties in a fair manner since its introduction in eurocrypt 2004 removing the random oracle heuristic in the security analysis of a concurrent signature scheme has become an open problem and the security of all the existing provably secure schemes could have only been done in the random oracle model while it has been known that the security in the random oracle model may not be guaranteed when the underlying random oracles are replaced by real life hash functions in this paper we solve this open problem by proposing a new concurrent signature scheme which allows us to prove its security without random oracles the security model we consider in this paper also slightly differs from previous works signatures before revealing the keystone are strongly ambiguous or anonymous in the sense that everyone is able to produce signatures that are indistinguishable from those generated honestly by the parties involved in the exchange while signatures after revealing the keystone remain unforgeable without sacrificing the fairness property in the multi user setting and without random oracles we prove the security of our scheme based on the intractability of computational diffie hellman cdh problem and collision resistance of hash functions

determining lyapunov exponents from a time series we present the first algorithms that allow the estimation of non negative lyapunov exponents from an experimental time series lyapunov exponents which provide a qualitative and quantitative characterization of dynamical behavior are related to the exponentially fast divergence or convergence of nearby orbits in phase space a system with one or more positive lyapunov exponents is defined to be chaotic our method is rooted conceptually in a previously developed technique that could only be applied to analytically defined model systems we monitor the long term growth rate of small volume elements in an attractor the method is tested on model systems with known lyapunov spectra and applied to data for the belousov zhabotinskii reaction and couette taylor flow

on the relationship between modular functions and copulas copulas are nothing else but supermodular functions with absorbing element 0 and neutral element 1 although a copula c cannot be modular on the unit square itself it is effectively so on every rectangle with zero c volume in this paper we show that an appropriate modular function on the unit square can be transformed into a copula by performing a simple truncation operation either from below or above to ensure the compatibility with the frechet hoeffding bounds modular functions on the unit square admit an additive representation in terms of two univariate functions we specifically focus on cases where these univariate functions are sections horizontal vertical diagonal of a given copula ample illustrations are provided

biconic aggregation functions we introduce a new method to construct aggregation functions these aggregation functions are called biconic aggregation functions with a given diagonal resp opposite diagonal section and their construction is based on linear interpolation on segments connecting the diagonal resp opposite diagonal of the unit square to the points 0 1 and 1 0 resp 0 0 and 1 1 subclasses of biconic aggregation functions such as biconic semi copulas biconic quasi copulas and biconic copulas are studied in detail

2 increasing binary aggregation operators abstract in this work we investigate the class of binary aggregation operators agops satisfying the 2 increasing property obtaining some characterizations for agops having other special properties e g quasi arithmetic mean choquet integral based modularity and presenting some construction methods in particular the notion of p increasing function is used in order to characterize the composition of 2 increasing agops the lattice structure with respect to the pointwise order of some subclasses of 2 increasing agops is presented finally a method is given for constructing copulas beginning from 2 increasing and 1 lipschitz agops

an optimal algorithm for assigning cryptographic keys to control access in a hierarchy a cryptographic scheme for controlling access to information within a group of users organized in a hierarchy was proposed in 1 the scheme enables a user at some level to compute from his own cryptographic key the keys of the users below him in the organization

certificateless threshold signature scheme from bilinear maps a t n threshold signature scheme allows t or more group members to generate signatures on behalf of a group with n members in contrast to the traditional public key cryptography based on public key infrastructure pki and identity based public key cryptography id pkc certificateless public key cryptography cl pkc offers useful properties as it does not require any certificates to ensure the authenticity of public keys and the key escrow problem is eliminated in this paper we investigate the notion of threshold signature schemes in cl pkc we start by pointing out the drawbacks in the two existing certificateless threshold signature schemes subsequently we present an elaborate description of a generic certificateless t n threshold signature scheme with a new security model the adversaries captured in the new model are more powerful than those considered in the existing schemes furthermore we establish the simulatability for certificateless threshold signature schemes and prove the relationship between the security of certificateless threshold signature schemes and that of the underlying non threshold certificateless signature schemes as an instantiation we present a concrete certificateless threshold signature scheme based on bilinear maps using the techniques of verifiable secret sharing and distributed key generation the proposed scheme is shown to be existentially unforgeable against adaptively chosen message attacks assuming the hardness of computational diffie hellman cdh problem

on the use of aggregation operations in information fusion processes this position paper discusses the role of the existing body of fuzzy set aggregation operations in various kinds of problems where the process of fusion of items coming from several sources is central several kinds of membership functions can be useful according to the nature of the information to be merged numerical vs ordinal inputs preferences vs uncertain data observations vs constraints in each case some aggregation operations look more plausible or feasible than others the aim of this discussion is to suggest directions for putting at work the results of recent mathematical investigations in the structure of aggregation operations

nonlinear dynamics of phonations in excised larynx experiments nonlinear dynamic methods including correlation dimension and lyapunov exponents are applied to quantitatively analyze phonations in excised larynx experiments irregular phonations are typically characterized by aperiodic waveforms and broadband spectra finite correlation dimensions and positive lyapunov exponents of irregular phonations demonstrate the existence of chaos in excised larynx phonations furthermore the correlation dimension maximal lyapunov exponent jitter shimmer and peak prominence ratio are used to statistically distinguish irregular phonations from normal phonations the correlation dimension and maximal lyapunov exponent indicate a significant difference between irregular and normal phonations however jitter shimmer and peak prominence ratio do not reveal such a significant difference and thus are unsuitable to differentiate between irregular phonations and normal phonations these findings might potentially assist investigators in understanding rough phonations and developing clinically valuable methodologies for the diagnosis of voice disorders

quadratic constructions of copulas in the paper we introduce and study quadratic constructions of copulas based on composition of a copula and some quadratic polynomial we characterize all quadratic polynomials whose composition with an arbitrary copula always results in a copula due to this result we can assign a two parametric class k c c d of copulas with parameters c d in a certain subset r 2 to each copula c moreover we also determine all copulas invariant with respect to the quadratic constructions presented this investigation brings two interesting parametric classes of copulas we show that the union of these two classes is equal to the so called plackett family of copulas we add some properties of these copulas and their statistical consequences

hidden attribute based signatures without anonymity revocation we propose a new notion called hidden attribute based signature which is inspired by the recent developments in attribute based cryptosystem with this technique users are able to sign messages with any subset of their attributes issued from an attribute center in this notion a signature attests not to the identity of the individual who endorsed a message but instead to a claim regarding the attributes the underlying signer possesses users cannot forge signature with attributes which they have not been issued furthermore signer remains anonymous without the fear of revocation among all users with the attributes purported in the signature after formalizing the security model we propose two constructions of hidden attribute based signature from pairings the first construction supports a large universe of attributes and its security proof relies on the random oracle assumption which can be removed in the second construction both constructions have proven to be secure under the standard computational diffie hellman assumption

two extensions of the ring signature scheme of rivest shamir taumann two extensions of rst rivest shamir and taumann ring signature are proposed which keep the form of rst ring signature unchanged one extension is to implement the verifiability property with which the real signer is able to prove that she actually signed the ring signature if she publishes her secret value in contrast to the available verifiable ring signatures this scheme is very simple secure and efficient in this scheme only the glue value of rst ring signature is replaced by the output of a hash function which takes as input a secret value and some signature parameters and the real signer is able to prove himself any times the other extension is to construct an anonymous subliminal channel in rst ring signature so that the subliminal sender the real signer is able to keep herself subliminal anonymous to the subliminal receiver the subliminal anonymity is implemented for the first time in this paper in addition if the sender wants to revoke the subliminal anonymity she is able to use the first extension

piecewise linear aggregation functions based on triangulation we introduce a method to construct piecewise linear binary aggregation functions on the unit interval based on a triangulation of the unit square with one additional vertex we derive conditions under which such piecewise linear aggregation functions possess additional interesting properties such as idempotence symmetry lipschitz continuity and 2 monotonicity this construction method can also be used to approximate binary aggregation functions in this way copulas and quasi copulas are approximated by singular copulas

on representations of 2 increasing binary aggregation functions in this paper we provide two different representations of 2 increasing binary aggregation functions by means of their lower and upper margins and a suitable copula

chaos in segments from korean traditional singing and western singing the time series of the segments from a korean traditional song gwansanyungma and a western song la mamma morta were investigated using chaotic analysis techniques it is found that the phase portrait in the reconstructed state space of the time series of the segment from the korean traditional song has a more complex structure in comparison with the segment from the western songs the segment from the korean traditional song has the correlation dimension 4 4 and two positive lyapunov exponents which show that the dynamic related to the korean traditional song is a high dimensional hyperchaotic process on the other hand the segment from the western song with only one positive lyapunov exponent and the correlation dimension 2 5 exhibits low dimensional chaotic behavior

computation of lyapunov spectra effect of interactive noise and application to a chemical oscillator abstract a refined version of the sano sawada algorithm to compute lyapunov spectra has been implemented and tested with several models which include periodic chaotic and hyperchaotic attractors under conditions designed to mimic experimental situations it was found that reliable lyapunov exponents can be obtained for time series of moderate length and point density also in the presence of interactive noise as long as its amplitude does not exceed 1 of the oscillation amplitude the algorithm was then applied to experimental data from the co oxidation on pt 110 clearly showing the occurrence of chaos as well as hyperchaos

aggregation functions means this two part state of the art overview on aggregation theory summarizes the essential information concerning aggregation issues an overview of aggregation properties is given including the basic classification on aggregation functions in this first part the stress is put on means i e averaging aggregation functions both with fixed arity n ary means and with multiple arities extended means

on the class of bivariate archimax copulas under constraints abstract the class of bivariate archimax copulas spans a broad range of dependence however its size is much reduced when the degree of association is prespecified the extent of this reduction is studied for a large set of measures of association the cases of exchangeable and non exchangeable archimax copulas are both considered

multivariate upper semilinear copulas in the problem setting of constructing an n copula given its diagonal section and all of its n 1 dimensional marginals we introduce a new class of symmetric n copulas which generalizes the well known class of bivariate upper semilinear copulas these new upper semilinear n copulas are constructed by linear interpolation on segments connecting the main diagonal of the unit hypercube 0 1n to one of its upper faces we focus on the case where the n 1 dimensional marginals are upper semilinear n 1 copulas themselves in which case the n copula is actually constructed given its diagonal section and the diagonal sections of its k marginals k 2 3 n 1 we provide necessary and sufficient conditions on these diagonal sections that guarantee that the upper semilinear construction method yields an n copula several examples are provided

cryptanalysis and improvement of an access control in user hierarchy based on elliptic curve cryptosystem in a key management scheme for hierarchy based access control each security class having higher clearance can derive the cryptographic secret keys of its other security classes having lower clearances in 2008 chung et al proposed an efficient scheme on access control in user hierarchy based on elliptic curve cryptosystem information sciences 178 1 2008 230 243 their scheme provides solution of key management efficiently for dynamic access problems however in this paper we propose an attack on chung et al s scheme to show that chung et al s scheme is insecure against the exterior root finding attack we show that under this attack an attacker adversary who is not a user in any security class in a user hierarchy attempts to derive the secret key of a security class by using the root finding algorithm in order to remedy this attack we further propose a simple improvement on chung et al s scheme overall the main theme of this paper is very simple a security flaw is presented on chung et al s scheme and then a fix is provided in order to remedy the security flaw found in chung et al s scheme

nonlinear dynamic analysis of voices before and after surgical excision of vocal polyps phase space reconstruction correlation dimension and second order entropy methods from nonlinear dynamics are used to analyze sustained vowels generated by patients before and after surgical excision of vocal polyps two conventional acoustic perturbation parameters jitter and shimmer are also employed to analyze voices before and after surgery presurgical and postsurgical analyses of jitter shimmer correlation dimension and second order entropy are statistically compared correlation dimension and second order entropy show a statistically significant decrease after surgery indicating reduced complexity and higher predictability of postsurgical voice dynamics there is not a significant postsurgical difference in shimmer although jitter shows a significant postsurgical decrease the results suggest that jitter and shimmer should be applied to analyze disordered voices with caution however nonlinear dynamic methods may be useful for analyzing abnormal vocal function and quantitatively evaluating the effects of surgical excision of vocal polyps

forward secure identity based signature security notions and construction the security of traditional identity based signatures wholly depends on the security of secret keys exposure of secret keys requires reissuing all previously assigned signatures this limitation becomes more obvious today as key exposure is more common with increasing use of mobile and unprotected devices under this background mitigating the damage of key exposure in identity based signatures is an important problem to deal with this problem we propose to integrate forward security into identity based signatures in this paper we firstly formalize the definition and security notions for forward secure identity based signature scheme and then construct an efficient scheme all parameters in our scheme have at most log squared complexity in terms of the total number of time periods the scheme is provably secure without random oracles

new families of symmetric asymmetric copulas abstract in 2004 rodriguez lallena and ubeda flores have introduced a class of bivariate copulas which generalizes some known families such as the farlie gumbel morgenstern distributions in 2006 dolati and ubeda flores presented multivariate generalizations of this class also they investigated symmetry dependence concepts and measuring the dependence among the components of each classes in this paper a new method of constructing binary copulas is introduced extending the original study of rodriguez lallena and ubeda flores to new families of symmetric asymmetric copulas several properties and parameters of newly introduced copulas are included among others relationship of our construction method with several kinds of ordinal sums of copulas is clarified

acoustic characteristics of phonation in wet voice conditions a perceptible change in phonation characteristics after a swallow has long been considered evidence that food and or drink material has entered the laryngeal vestibule and is on the surface of the vocal folds as they vibrate the current paper investigates the acoustic characteristics of phonation when liquid material is present on the vocal folds using ex vivo porcine larynges as a model consistent with instrumental examinations of swallowing disorders or dysphagia in humans three liquids of different varibar viscosity thin liquid nectar and honey were studied at constant volume the presence of materials on the folds during phonation was generally found to suppress the higher frequency harmonics and generate intermittent additional frequencies in the low and high end of the acoustic spectrum perturbation measures showed a higher percentage of jitter and shimmer when liquid material was present on the folds during phonation but they were unable to differentiate statistically between the three fluid conditions the finite correlation dimension and positive lyapunov exponent measures indicated that the presence of materials on the vocal folds excited a chaotic system further these measures were able to reliably differentiate between the baseline and different types of liquid on the vocal folds

characterization of experimental time series from taylor couette flow abstract rotational taylor couette flow shows a rich variety of well defined and controllable scenarios even for short cylinders where the number of possible flow states is found to be very small period doubling cascades intermittencies homoclinic orbits and n tori can be found depending on boundary conditions we characterize these flow states by fractal dimensions lyapunov spectra and entropies in the experiments the axial velocity component was measured using laser doppler anemometry and the phase space was reconstructed by using delay time coordinates a simple noise reduction algorithm was applied to the noisy data set to improve the accuracy of the estimation of the dynamical variables

characterization of strange attractors a new measure of strange attractors is introduced which offers a practical algorithm to determine their character from the time series of a single observable the relation of this new measure to fractal dimension and information theoretic entropy is discussed

the role of generalized convexity in conic copula constructions abstract inspired by the notion of a conic semi copula we introduce upper conic lower conic and biconic semi copulas with a given section such semi copulas are constructed by linear interpolation on segments connecting the graph of a strict negation operator to the points 0 0 and or 1 1 the important subclasses of upper conic lower conic and biconic quasi copulas with a given section are characterized the notion of generalized convexity turns out to play a key role in this characterization some examples are also provided

structure of left continuous triangular norms with strong induced negations iii construction and decomposition this paper is the continuation of jenei j appl non classical logics 10 2000 83 92 11 2001 351 366 where the rotation construction and the rotation annihilation construction have been presented respectively both constructions produce left continuous but not continuous triangular norms with strong induced negations here we show that these two constructions allow us to define indecomposability and that each decomposable left continuous triangular norm with strong induced negation can be derived as result of one of the above constructions in this way two general decomposition theorems arise in addition the decomposition of left continuous triangular norms with strong induced negations can be defined in a unique way namely when the decomposition is done by the minimal decomposition point

on a family of multivariate copulas for aggregation processes we introduce a family of multivariate copulas a special type of n ary aggregation operations depending on a univariate function this family is used in the construction of a special aggregation operation that satisfies a lipschitz condition several examples are provided and some statistical properties are studied