observer and global output feedback stabilisation for some mechanical systems the objective of the work is two fold a first part is devoted to the problem of constructing an observer to the practical system called overhead crane with the position as output in a second part the problem of global output feedback stabilisation is solved for a class of euler lagrange systems when the variables of velocity are the unmeasured part of the state the equations of these systems are non linear with respect to the velocities a new output feedback control scheme is proposed it relies on the determination of a change of coordinates which gives to the systems a triangular form to illustrate the approach it is applied to a two link manipulator

quasi and pseudo inverses of monotone functions and the construction of t norms abstract several properties of quasi and pseudo inverses of a non decreasing real function are discussed based on a result of schweizer and sklar for a given triangular norm t and non decreasing function f a construction method leading to a commutative fully ordered semigroup on the unit interval is given a similar construction based on the pseudo inverse implies that the resulting operation will be bounded from above by the minimum but then the associativity may be violated several sufficient conditions for constructing new t norms from a given one and a non decreasing function f based on its quasi inverses and on its pseudo inverse respectively are discussed together with illustrative examples

discrete choquet integral and some of its symmetric extensions classical extensions of the choquet integral defined on 0 1 to 1 1 are the asymmetric and the symmetric choquet integral the second one being called also the sipos integral recently the balancing choquet integral was introduced as another kind of a symmetric extension of the discrete choquet integral we introduce and discuss a new type of such extension the fusion choquet integral and discuss its properties and relationship to the balancing and the symmetric choquet integral the symmetric maximum introduced by grabisch is shown to be a special case of the fusion and the balancing choquet integral several extensions of owa operators are also discussed

on sugeno integral as an aggregation function the sugeno integral for a given fuzzy measure is studied under the viewpoint of aggregation in particular we give some equivalent expressions of it we also give an axiomatic characterization of the class of all the sugeno integrals some particular subclasses such as the weighted maximum and minimum functions are investigated as well

energy and entropy based stabilization for lossless dynamical systems via hybrid controllers a novel class of dynamic energy based hybrid controllers is proposed as a means for achieving enhanced energy dissipation in lossless dynamical systems these dynamic controllers combine a logical switching architecture with continuous dynamics to guarantee that the system plant energy is strictly decreasing across switchings the general framework leads to closed loop systems described by impulsive differential equations in addition we construct hybrid dynamic controllers that guarantee that the closed loop system is consistent with basic thermodynamic principles in particular the existence of an entropy function for the closed loop system is established that satisfies a hybrid clausius type inequality special cases of energy based and entropy based hybrid controllers involving state dependent switching are described

solutions to hybrid inclusions via set and graphical convergence with stability theory applications motivated by questions in stability theory for hybrid dynamical systems we establish some fundamental properties of the set of solutions to such systems using the notion of a hybrid time domain and general results on set and graphical convergence we establish under weak regularity and local boundedness assumptions that the set of solutions is sequentially compact and upper semicontinuous with respect to initial conditions and system perturbations the general facts are then used to establish several results for the behavior of hybrid systems that have asymptotically stable compact sets these results parallel what is already known for differential inclusions and difference inclusions for example the basin of attraction for a compact attractor is relatively open the attractivity is uniform from compact subsets of the basin of attraction and asymptotic stability is robust with respect to small perturbations

higher order sliding mode observers with scaled dissipative stabilisers abstractthis paper proposes a global theoretically exact finite time convergent observer for a class of nonlinear systems which are not necessarily bounded input bounded state with respect to the unknown inputs with this aim a scaled dissipative stabiliser is suggested ensuring that the highest derivative of the output estimation error is independent from the stabiliser gains after this a higher order sliding mode differentiator with the gains adjusted to the upper bound of the unknown inputs is applied achieving finite time convergence

multifractal properties of price change and volume change of stock market indices abstract we study auto correlations and cross correlations of daily price changes and daily volume changes of thirteen global stock market indices using multifractal detrended fluctuation analysis mf dfa and multifractal detrended cross correlation analysis mf dxa we find rather distinct multifractal behavior of price and volume changes our results indicate that the time series of price changes are more complex than those of volume changes and that large fluctuations dominate multifractal behavior of price changes while small fluctuations dominate multifractal behavior of volume changes we also find that there is an absence of correlations in price changes there are anti persistent long term correlations in volume changes and there are anti persistent long term cross correlations between price and volume changes shuffling the series reveals that multifractality of both price changes and volume changes arises from a broad probability density function

the symmetric sugeno integral we propose an extension of the sugeno integral for negative numbers in the spirit of the symmetric extension of choquet integral also called sipos integral our framework is purely ordinal since the sugeno integral has its interest when the underlying structure is ordinal we begin by defining negative numbers on a linearly ordered set and we endow this new structure with a suitable algebra very close to the ring of real numbers in a second step we introduce the mobius transform on this new structure lastly we define the symmetric sugeno integral and show its similarity with the symmetric choquet integral

bipolar fuzzy integrals in decision analysis and especially in multiple criteria decision analysis several non additive integrals have been introduced in the last 60 years these include the choquet integral the shilkret integral and the sugeno integral among others recently a bipolar choquet integral was proposed for cases in which the underlying scale is bipolar in this paper we propose a bipolar shilkret integral and a bipolar sugeno integral moreover we provide an axiomatic characterization of all three bipolar fuzzy integrals

continuous triangular subnorms triangular subnorms are associative commutative non decreasing operations on the unit interval upper bounded by the minimum continuous triangular subnorms are shown to be ordinal sum of archimedean continuous t subnorms with at most one proper t subnorm summand special attention is paid to generate continuous t subnorms an application of continuous t subnorms to the construction of left continuous t norms is shown several illustrative examples are included

sugeno integral based on absolutely monotone real set functions the class of all absolutely monotone and sign stable set functions with m a 0 denoted by amss is introduced necessary and sufficient conditions are obtained for a set function m m a 0 to be a member of amss a sugeno type integral of an a measurable real valued function is defined with respect to an absolutely monotone and sign stable set function and some of its properties are shown a representation of a comonotone cosigned additive functional by sugeno integral based on m amss is obtained

on additive generators of overlap functions in this paper we introduce the notion of additive generator pair for overlap functions we also study how some of the properties that can be demanded to an overlap function can be expressed in terms of its generator pair in particular given a continuous and positive t norm t we analyze the overlap functions which are obtained by the distortion of t by a pseudo automorphism showing that the additive generator pair of such overlap function may be given in terms of the considered pseudo automorphism and the additive generator of t finally we also consider the influence of the migrativity homogeneity and idempotency properties for the overlap functions obtained by such distortion in terms of their respective additive generator pairs

quantifying cross correlation between ibovespa and brazilian blue chips the dcca approach abstract the objective of this paper is to demonstrate the influence of the blue chips companies in the stock market in this we apply the detrended cross correlation coefficient dcca at the sao paulo stock market ibovespa brazil initially we found that there is a positive cross correlation between these companies and the index afterwards we show that the cross correlation coefficient value depends on the time scale and the specific company blue chips thus this type of analysis lets to infer what is the most adherent company with ibovespa also in this paper we analyze in the point of view of dcca the 2008 financial crisis before after altogether the results show that there is more cross correlation between ibovespa index the blue chips after the 2008 crisis

statistical properties of the volatility of price fluctuations we study the statistical properties of volatility measured by locally averaging over a time window t the absolute value of price changes over a short time interval ensuremath delta t we analyze the s 500 stock index for the 13 year period jan 1984 to dec 1996 we find that the cumulative distribution of the volatility is consistent with a power law asymptotic behavior characterized by an exponent ensuremath mu ensuremath approx 3 similar to what is found for the distribution of price changes the volatility distribution retains the same functional form for a range of values of t further we study the volatility correlations by using the power spectrum analysis both methods support a power law decay of the correlation function and give consistent estimates of the relevant scaling exponents also both methods show the presence of a crossover at approximately 1 5 days in addition we extend these results to the volatility of individual companies by analyzing a data base comprising all trades for the largest 500 u s companies over the two year period jan 1994 to dec 1995

some observations about the convex combination of continuous triangular norms abstract the convex combination of continuous triangular norms is discussed let c 1 be the class of all nilpotent t norms c 2 be the class of all strict t norms and c 3 be the class of all continuous non archimedean t norms it is shown that for any t norms t 1 t 2 which are taken from two different classes of c i i 1 2 3 the convex combination t 1 t 1 t 2 is not associative for any 0 1 the case of two continuous non archimedean t norms is also investigated by our results the problem of whether or not two continuous t norms can be combined with each other is reduced to that of whether two strict or two nilpotent t norms can be combined with each other or not

the bounded convergence in measure theorem for nonlinear integral functionals in this paper we introduce a new notion of the perturbation of nonlinear functionals to formulate a functional form of the convergence theorems for nonlinear integrals in nonadditive measure theory as its direct consequences we obtain the bounded convergence in measure theorems for typical nonlinear integrals which show that the autocontinuity of a nonadditive measure is equivalent to the validity of the bounded convergence in measure theorems for the choquet the sugeno and the shilkret integrals as well as their symmetric and asymmetric extensions

cross correlations between volume change and price change in finance one usually deals not with prices but with growth rates r defined as the difference in logarithm between two consecutive prices here we consider not the trading volume but rather the volume growth rate r the difference in logarithm between two consecutive values of trading volume to this end we use several methods to analyze the properties of volume changes r and their relationship to price changes r we analyze 14 981 daily recordings of the standard and poor s s p 500 index over the 59 year period 1950 2009 and find power law cross correlations between r and r by using detrended cross correlation analysis dcca we introduce a joint stochastic process that models these cross correlations motivated by the relationship between r and r we estimate the tail exponent of the probability density function p r r 1 for both the s p 500 index as well as the collection of 1819 constituents of the new york stock exchange composite index on 17 july 2009 as a new method to estimate we calculate the time intervals q between events where r q we demonstrate that q the average of q obeys q q we find 3 furthermore by aggregating all q values of 28 global financial indices we also observe an approximate inverse cubic law

brief energy based control for hybrid port controlled hamiltonian systems in this paper we develop an energy based hybrid control framework for hybrid port controlled hamiltonian systems in particular we obtain constructive sufficient conditions for hybrid feedback stabilization that provide a shaped energy function for the closed loop system while preserving a hybrid hamiltonian structure at the closed loop level furthermore an inverse optimal hybrid feedback control framework is developed that characterizes a class of globally stabilizing energy based controllers that guarantee hybrid sector and gain margins to multiplicative input uncertainty of hybrid hamiltonian systems

an invariance principle for nonlinear hybrid and impulsive dynamical systems in this paper we develop an invariance principle for dynamical systems possessing left continuous flows specifically we show that left continuity of the system trajectories in time for each fixed state point and continuity of the system trajectory in the state for every time in some dense subset of the semi infinite interval are sufficient for establishing an invariance principle for hybrid and impulsive dynamical systems as a special case of this result we state and prove new invariant set stability theorems for a class of nonlinear impulsive dynamical systems namely state dependent impulsive dynamical systems these results provide less conservative stability conditions for impulsive systems as compared to classical results in the literature and allow us to address the stability of limit cycles and periodic orbits of impulsive systems

information flow between ibovespa and constituent companies abstract we study the direction of information flow between ibovespa index and its constituent companies using the transfer entropy method we find stronger information transfer from individual stocks towards the composite index than in the opposite direction our results differ from those found for developed market where market index was identified as driving force indicating that the role of index increases with the maturity of the market

fuzzy measures and integrals we present fuzzy measures and fuzzy integrals as special poset homeomorphisms besides general fuzzy integrals regular fuzzy integrals are introduced and some of their properties are discussed state of art of fuzzy measure and fuzzy integral theory are briefly summarized and some further streaming is sketched

generators of copulas and aggregation the most applied class of copulas for fitting purposes is undoubtedly the class of archimedean copulas due to their representation by means of single functions of one variable i e by means of additive generators or the corresponding pseudo inverses in this paper we characterize aggregation functions preserving additive generators pseudo inverses of additive generators of archimedean copulas as a by product we obtain an efficient method to construct new additive generators from some given ones

stabilization of hamiltonian systems 1 hamiltonian systems in this paper we will be concerned with the stabilization by feedback of hamiltonian systems in order to facilitate our discussions especially when applying lyapunov s second method we will restrict ourselves to a particular although natural subclass of hamiltonian systems given in the following way l let q be an n dimensional smooth manifold denoting the configuration space and let t q be the cotangent bundle denoting the phase space or srufe space furthermore there is a smooth m dimensional output manifold y m n and a smooth output map c q y smooth will mean c or ck with k sufficiently big although we shall restrict ourselves in the second part of section 2 to analytic data for simplicity we take c to be submersive so rank dc q m we assume that the system on t q has an internal energy which is the sum of a kinetic energy k and a porentiul energy v this means that there exists a riemannian metric on q in local coordinates q q j for q given by

dependence of exchangeable residual lifetimes subject to failure abstract we provide exact formulas about the survival copula of an exchangeable random vector of residual lifetimes when some of the components have failed specific computations are carried out in the case of archimedean copulas and the evolution of dependence after successive failures of some components is shown numerically via measures of association

on the convex combination of td and continuous triangular norms the problem of when t l 1 l t d lt l 0 1 is a triangular norm where t d is the drastic product and t is a continuous triangular norm is studied it is shown that t l cannot be a triangular norm when t is nilpotent it is also shown that t l is a triangular norm if t is strict and its additive generator f satisfies f lx f x f l for all x 0 1 the cases that t t m and t is the ordinal sum of continuous archimedean summands are also discussed some left continuous t norms which can be combined with each other are given

new class of control laws for robotic manipulators part 1 non adaptive case a new class of exponentially stabilizing control laws for joint level control of robot arms is introduced it has recently been recognized that the non linear dynamics associated with robotic manip

fundamental properties of reset control systems reset controllers are linear controllers that reset some of their states to zero when their input is zero we are interested in their feedback connection with linear plants and in this paper we establish fundamental closed loop properties including stability and asymptotic tracking this paper considers more general reset structures than previously considered allowing for higher order controllers and partial state resetting it gives a testable necessary and sufficient condition for quadratic stability and links it to both uniform bounded input bounded state stability and steady state performance unlike previous related research which includes the study of impulsive differential equations our stability results require no assumptions on the evolution of reset times

optimal disturbance rejection control for nonlinear impulsive dynamical systems in this paper we develop an optimality based framework for addressing the problem of nonlinear nonquadratic hybrid control for disturbance rejection of nonlinear impulsive dynamical systems with bounded exogenous disturbances specifically we transform a given nonlinear nonquadratic hybrid performance criterion to account for system disturbances as a consequence the disturbance rejection problem is translatedinto an optimal hybridcontrol problem furthermore the resulting optimal hybrid control law is shown to render the closed loop nonlinear input output map dissipative with respect to general supply rates in addition the lyapunov function guaranteeing closed loop stability is shown to be a solution to a stead y state hybridhamilton jacobi isaacs equation andthus guaranteeing optimality 2005 elsevier ltd all rights reserved

interconnection and damping assignment passivity based control of port controlled hamiltonian systems passivity based control pbc is a well established technique that has shown to be very powerful to design robust controllers for physical systems described by euler lagrange el equations of motion for regulation problems of mechanical systems which can be stabilized shaping only the potential energy pbc preserves the el structure and furthermore assigns a closed loop energy function equal to the difference between the energy of the system and the energy supplied by the controller thus we say that stabilization is achieved via energy balancing unfortunately these nice properties of el pbc are lost when used in other applications which require shaping of the total energy for instance in electrical or electromechanical systems or even some underactuated mechanical devices our main objective in this paper is to develop a new pbc theory which extends to a broader class of systems the aforementioned energy balancing stabilization mechanism and the structure invariance towards this end we depart from the el description of the systems and consider instead port controlled hamiltonian models which result from the network modelling of energy conserving lumped parameter physical systems with independent storage elements and strictly contain the class of el models

componentwise decomposition of some lattice valued fuzzy integrals lattice valued fuzzy measures are lattice valued set functions which assign the bottom element of the lattice to the empty set the top element of the lattice to the entire universe and satisfy the property of monotonicity if the lattice is complete then a lattice valued fuzzy integral of sugeno type with similar properties such as the sugeno integral in its original form can be introduced in a natural way the main result of the paper is a componentwise decomposition theorem of an l valued fuzzy integral to its l valued fuzzy integrals components where l is a complete lattice with negation and l a b a email protected l a email protected is organized as a complete lattice too this result is useful to obtain the properties of l valued fuzzy integrals from the properties of l valued fuzzy integrals and to calculate in a simple way the values of some integrals from the values of the components the important case l 0 1 when l becomes the lattice of the intuitionistic fuzzy values is distinctly discussed an idea of application to synthetic evaluation of objects is also suggested

discrete bipolar universal integrals the concept of universal integral recently proposed generalizes the choquet shilkret and sugeno integrals those integrals admit a discrete bipolar formulation useful in those situations where the underlying scale is bipolar in this paper we propose the concept of discrete bipolar universal integral in order to provide a common framework for bipolar discrete integrals including as special cases the discrete choquet shilkret and sugeno bipolar integrals moreover we provide two different axiomatic characterizations of the proposed discrete bipolar universal integral

modeling and adaptive tracking for a class of stochastic lagrangian control systems this paper focuses on the problem of modeling and adaptive tracking for a class of stochastic lagrangian control systems with unknown parameters by reasonably introducing random noise a method to construct stochastic lagrangian control systems is given under some milder assumptions an adaptive tracking controller is designed such that the mean square of the tracking error converges to an arbitrarily small neighborhood of zero by tuning design parameters the reasonability of assumptions and the efficiency of the controller are demonstrated by a mechanics model in random vibration environment

lipschitz continuity of triangular subnorms this paper deals with the lipschitz property of triangular subnorms unlike the case of triangular norms for these operations the problem is still open and presents an interesting variety of situations we provide some characterization results by weakening the notion of convexity introducing two generalized versions of convexity for real functions called a lower convexity and sub convexity the a lower convex and sub convex real mappings present characteristics quite different from the usual convex real mappings we will discuss the link between such kind of functions and the generators and their pseudo inverse of continuous archimedean triangular subnorms

a representation of a comonotone x additive and monotone functional by two sugeno integrals there is obtained a representation of a email protected email protected additive weak email protected homogeneous and monotone functional l defined on the class of functions on finite set as a symmetric maximum of two sugeno integrals this representation is a generalization of certain previous results which are useful for cumulative prospect theory as a consequence of a result on general fuzzy rank and sign dependent functionals considered on functions defined on the infinitely countable basic set x it is obtained that the symmetric sugeno integral is email protected email protected additive functional on the class of functions with finite support

global attractors for impulsive dynamical systems a precompact approach abstract in this work we give the definition of a global attractor of an impulsive dynamical system and obtain several important properties for this class of attractors we prove the theorem on existence of such attractors and apply it to chosen ordinary and partial differential equations with impulsive functions

discrete bipolar pseudo integrals abstract in the authors paper strboja et al 2016 42 the notion of the bipolar pseudo integral has been introduced this paper extends investigations related to this new type of bipolar integrals defined with respect to decomposable bi capacities we consider the main properties of the discrete bipolar pseudo integral a characterization theorem for the discrete bipolar pseudo integral is proven monotone convergence theorems and the fatou type lemma for the discrete bipolar pseudo integral are considered in order to illustrate obtained results many interesting examples are provided

position feedback global tracking control of el systems a state transformation approach the contribution of this paper is a dynamic position feedback global tracking controller for fully actuated euler lagrange el systems the properties we show for the closed loop system are uniform stability and exponential convergence global in the initial tracking errors and semiglobal in the initial estimation errors the novelty of our approach is that our observer and control design are based on a new model for el systems which is linear in the immeasurable velocities this model is shown to fit robot manipulators we also provide some simulation results

weighted aggregation operators based on minimization minimization based aggregation operators a g d are discussed special attention is paid to weighting function g based cases related to some fixed dissimilarity function d when d 2 x y x y 2 we recognize mixture operators and we recall some sufficient conditions for g ensuring the monotonicity of a g d for d 1 x y x y and non decreasing non increasing g a g d is shown to be the upper lower median whenever a g d is an aggregation operator

a note to a construction of t norms based on pseudo inverses of monotone functions abstract many constructions of t norms are known in the literature this paper discusses a construction of t norms by pseudo inverse of a non decreasing function the necessity and the sufficiency of some conditions of this construction are analyzed some easily verifiable sufficient conditions of this construction are given

sharp bounds of jensen type for the generalized sugeno integral abstract in this paper we provide two sided attainable bounds of jensen type for the generalized sugeno integral of any measurable function the results extend the previous results of roman flores et al for increasing functions and abbaszadeh et al for convex and concave functions we also give corrections of some results of abbaszadeh et al as a by product we obtain sharp inequalities for symmetric integral of grabisch to the best of our knowledge the results in the real valued functions context are presented for the first time here

on some algebraic and topological properties of generated border continuous triangular norms in the class of all border continuous triangular norms generated by strictly decreasing additive generators the following algebraic and topological properties are studied in detail the continuity left continuity right continuity the border continuity the conditional cancellation law the cancellation law the archimedean property the diagonal property the continuity on the diagonal and also the associative law the relations among these properties are examined a special attention is devoted to the set of all idempotent elements of generated functions and to the set of all points of discontinuity of an additive generator the necessary and sufficient conditions for a generated function to be a border continuous triangular norm are expressed in terms of properties of generated functions some relevant examples and counterexamples are indicated

non linear impulsive dynamical systems part i stability and dissipativity in this paper we develop lyapunov and invariant set stability theorems for non linear impulsive dynamical systems furthermore we generalize dissipativity theory to non linear dynamical systems with impulsive effects specifically the classical concepts of system storage functions and supply rates are extended to impulsive dynamical systems providing a generalized hybrid system energy interpretation in terms of stored energy dissipated energy over the continuous time system dynamics and dissipated energy over the resetting instants furthermore extended kalman yakubovich popov conditions in terms of the impulsive system dynamics characterizing dissipativeness via system storage functions are derived finally the framework is specialized to passive and non expansive impulsive systems to provide a generalization of the classical notions of passivity and non expansivity for non linear impulsive systems these results are used in the second part of this paper to develop extensions of the small gain and p

1 f behavior in cross correlations between absolute returns in a us market abstract employing detrended fluctuation analysis dfa and detrended cross correlations analysis dcca we analyze auto correlations in the absolute returns for each of 30 dow jones industrial average djia constituents s i and cross correlations in the absolute returns between the djia and each s i we find that each djia member follows the djia in absolute returns since the dcca curve for each pair s i djia i exhibits strong cross correlations with average dcca exponent 1 03 0 04 this value for implies that the power law cross correlations are of the 1 f functional form for the financial firms comprising the djia we also find that the dfa and dcca exponents controlling the duration of firm risk are somewhat larger than the corresponding values for the rest of the us financial industry

adaptive control of time varying linear systems the authors present a global bounded input bounded state stability theory for a class of continuously adapting controllers applied to time varying linear systems this gives theoretical support to the application of many of the algorithms used in practice a key feature of the analysis is that no persistence of excitation requirement is needed

technical communique global output feedback tracking control for a class of lagrangian systems the problem of global tracking control without velocity measurement of the so called euler lagrange systems has been paid a lot of attention for the past several years in this note a nice property of one degree of freedom euler lagrange systems is highlighted which in particular allows us to obtain a new solution to the problem of tracking control for this class of systems the solution is under the form of a linear like observer based controller which gives fairly good results as illustrated in the simulation the method can be generalized to any system having the same property

residuated variants of sugeno integrals sugeno integrals and their particular cases such as weighted minimum and maximum have been used in multiple criteria aggregation when the evaluation scale is qualitative this paper proposes two new variants of weighted minimum and maximum where the criteria weights play the role of tolerance thresholds these variants require the use of a residuated structure equipped with an involutive negation we propose residuated counterparts of sugeno integrals where the weights bear on subsets of criteria and we study their properties showing they are analogous to sugeno integrals to a large extent finally we propose dual aggregation operations we call desintegrals where an item is evaluated in terms of its defects rather than in terms of its positive features desintegrals are maximal when no defects at all are present while integrals are maximal when all merits are sufficiently present qualitative integrals and desintegrals suggest a possible approach to bipolar evaluation processes where items are judged both in terms of merits and defects that are not independent of one another

distributed global output feedback control for a class of euler lagrange systems this paper investigates the distributed tracking control problem for a class of euler lagrange multiagent systems when the agents can only measure the positions in this case the lack of the separation principle and the strong nonlinearity in unmeasurable states pose severe technical challenges to global output feedback control design to overcome these difficulties a global nonsingular coordinate transformation matrix in the upper triangular form is first proposed such that the nonlinear dynamic model can be partially linearized with respect to the unmeasurable states and a new type of velocity observers is designed to estimate the unmeasurable velocities for each system then based on the outputs of the velocity observers we propose distributed control laws that enable the coordinated tracking control system to achieve uniform global exponential stability both theoretical analysis and numerical simulations are presented to validate the effectiveness of the proposed control scheme

non linear impulsive dynamical systems part ii stability of feedback interconnections and optimality in a companion paper nonlinear impulsive dynamical systems part i stability and dissipativity lyapunov and invariant set stability theorems and dissipativity theory were developed for non linear impulsive dynamical systems in this paper we build on these results to develop general stability criteria for feedback interconnections of non linear impulsive systems in addition a unified framework for hybrid feedback optimal and inverse optimal control involving a hybrid non linear non quadratic performance functional is developed it is shown that the hybrid cost functional can be evaluated in closed form as long as the cost functional considered is related in a specific way to an underlying lyapunov function that guarantees asymptotic stability of the non linear closed loop impulsive system furthermore the lyapunov function is shown to be a solution of a steady state hybrid hamilton jacobi bellman equation

a note on the ordinal sum theorem and its consequence for the construction of triangular norms in this paper the well known ordinal sum theorem of semigroups is generalized and applied to construct new families of triangular subnorms and triangular norms t norms among them one can find several new families of left continuous t norms too

multifractal analysis of managed and independent float exchange rates abstract we investigate multifractal properties of daily price changes in currency rates using the multifractal detrended fluctuation analysis mf dfa we analyze managed and independent floating currency rates in eight countries and determine the changes in multifractal spectrum when transitioning between the two regimes we find that after the transition from managed to independent float regime the changes in multifractal spectrum position of maximum and width indicate an increase in market efficiency the observed changes are more pronounced for developed countries that have a well established trading market after shuffling the series we find that the multifractality is due to both probability density function and long term correlations for managed float regime while for independent float regime multifractality is in most cases caused by broad probability density function

decision theoretic foundations of qualitative possibility theory abstract this paper presents a justification of two qualitative counterparts of the expected utility criterion for decision under uncertainty which only require bounded linearly ordered valuation sets for expressing uncertainty and preferences this is carried out in the style of savage starting with a set of acts equipped with a complete preordering relation conditions on acts are given that imply a possibilistic representation of the decision maker uncertainty in this framework pessimistic i e uncertainty averse as well as optimistic attitudes can be explicitly captured the approach thus proposes an operationally testable description of possibility theory

random matrix approach to cross correlations in financial data we analyze cross correlations between price fluctuations of different stocks using methods of random matrix theory rmt using two large databases we calculate cross correlation matrices c of returns constructed from i 30 min returns of 1000 us stocks for the 2 yr period 1994 1995 ii 30 min returns of 881 us stocks for the 2 yr period 1996 1997 and iii 1 day returns of 422 us stocks for the 35 yr period 1962 1996 we test the statistics of the eigenvalues lambda i of c against a null hypothesis a random correlation matrix constructed from mutually uncorrelated time series we find that a majority of the eigenvalues of c fall within the rmt bounds lambda lambda for the eigenvalues of random correlation matrices we test the eigenvalues of c within the rmt bound for universal properties of random matrices and find good agreement with the results for the gaussian orthogonal ensemble of random matrices implying a large degree of randomness in the measured cross correlation coefficients further we find that the distribution of eigenvector components for the eigenvectors corresponding to the eigenvalues outside the rmt bound display systematic deviations from the rmt prediction in addition we find that these deviating eigenvectors are stable in time we analyze the components of the deviating eigenvectors and find that the largest eigenvalue corresponds to an influence common to all stocks our analysis of the remaining deviating eigenvectors shows distinct groups whose identities correspond to conventionally identified business sectors finally we discuss applications to the construction of portfolios of stocks that have a stable ratio of risk to return less

on output feedback stabilization of euler lagrange systems with nondissipative forces this paper provides a solution to the problem of output feedback stabilization of systems described by euler lagrange equations perturbed by nondissipative forces this class of forces appears in some applications where we must take into account the interaction of the system with its environment the nonlinear dependence on the unmeasurable part of the state and the loss of the fundamental passivity property render most of the existing results on stabilization of nonlinear systems unapplicable to this problem the technique we use consists of finding a dynamic output feedback controller and a nonlinear change of coordinates such that the closed loop can be decomposed as a cascade of an asymptotically stable system and an input to state stable system this should be contrasted with the well known passivity based technique that aims at a feedback interconnection of passive systems we believe this design methodology to be of potential applicability to other stabilization problems where passivity arguments are unapplicable

fibred triangular norms abstract in this paper we deal with the formula g t f x f y where f g are functions mapping from the unit interval to itself and t is a triangular norm we are interested in the conditions under which this formula yields a triangular norm the case when f is continuous is investigated in detail as a result a new method which generates new triangular norms from an arbitrary triangular norm is developed these new triangular norms are the so called fibred triangular norms which are closely related to the homomorphism of semigroups it is well known that continuous archimedean triangular norms can be generated with additive generator functions we investigate a possible generalization of the additive generator function and characterize the class of t norms which can be generated with them this class turns out to be the class of fibred continuous archimedean t norms finally some examples are given for the case when f is not continuous

composite adaptive control of robot manipulators abstract adaptive control of linear time invariant single input single output systems has been extensively studied and a number of globally convergent controllers have been derived while extensions of the results to non linear or multivariable systems have rarely been achieved similar global convergence properties can indeed be obtained in the case of robot manipulators an important and unique class of non linear multi input multi output dynamic systems based on the observation that the parameter uncertainty is reflected in both the tracking error in joint motion and the prediction error in the joint torques or the power input we recently proposed a new class of adaptive robot controllers the parameter adaptation of which is driven by both tracking error and prediction error in this paper following a brief review of our earlier globally convergent direct adaptive controller we provide a detailed analysis of these composite adaptive controllers results on global asymptotic and exponential tracking convergence are established and confirmed by simulation

k order additive discrete fuzzy measures and their representation abstract in order to face with the complexity of discrete fuzzy measures we propose the concept of k orderadditive fuzzy measure including usual additive measures and fuzzy measures every discrete fuzzy measure is a k order additive fuzzy measure for a unique k a related topic of the paper is to introduce an alternative representation of fuzzy measures called the interaction representation which sets and extends in a common framework the shapley value and the interaction index proposed by murofushi and soneda

simple sliding mode control scheme applied to robot manipulators we present a simple sliding mode control scheme for robot manipulators that does not rely upon the construction of individually stable discontinuity surfaces thus greatly reducing the complexity of design we utilize the structure of the manipulator dynamics and lyapunov s second method in order to establish a sliding surface on the intersection of the switching surfaces in a direct manner a simple numerical example accompanies the theoretical development

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

dealing with time varying parameter problem of robot manipulators performing path tracking tasks using the properties of the element by element or hadamard product of matrices the authors obtain the robot dynamics in parameter isolated form from which a new control scheme is developed the controller proposed yields zero asymptotic tracking errors when applied to robotic systems with time varying parameters by using a switching type control law the results obtained are global in the initial state of the robot and can be applied to rapidly varying systems

averaging operators in fuzzy classification systems the averaging operators used for aggregation of outputs of fuzzy classification rules are examined several methods used in fuzzy rule based classification systems are discussed and related multi polar averaging operators are shown further new aggregation methods based on the idea used for the definition of owa operators are described the connection between multi polar averaging operators and the multi polar choquet integral is shown and using this connection the conditions under which are the respective averaging operators monotone are studied several examples of special multi polar owa operators with a relation to existing bipolar aggregation operators are included

dioids and semirings links to fuzzy sets and other applications besides the classical algebraic structures of groups rings and fields which have long been the almost exclusive reference concepts used in mathematical modelling other algebraic structures such as dioids and semirings have emerged in the last two or three decades in connection with modelling and solving a rich variety of non classical problems e g in decision analysis fuzzy set theory operations research automatic control and mathematical physics the present paper aims at providing an overview of applications of dioid and semiring structures stressing links with fuzzy sets and emphasizing linear algebraic problems solving linear systems computing eigenvalues and eigenvectors non classical path finding problems using algebras of endomorphisms and connections between dioid structure and nonlinear analysis in view of solving problems in mathematical physics

subjective probability and expected utility without additivity comonotic acts are defined and an axiom of comonotomic independence 19 introduced that weakens the von newmann morgenstern axiom of independence if a nondegenerate continuous and monotonic state independent weak order over acts satisfies comonotonic independence then it induces a unique non necessarily additive probability and a von neumann morgenstern utility an extension of theexpected utility theory covers situations as the ellsberg paradox which are inconsistent with additive expected utility the concept of uncertainty aversion and interpretation of comonotonic independence in the context of social welfare functions are included

speed observation and position feedback stabilization of partially linearizable mechanical systems the problems of speed observation and position feedback stabilization of mechanical systems are addressed in this paper our interest is centered on systems that can be rendered linear in the velocities via a partial change of coordinates it is shown that the class is fully characterized by the solvability of a set of partial differential equations pdes and strictly contains the class studied in the existing literature on linearization for speed observation or control a reduced order globally exponentially stable observer constructed using the immersion and invariance methodology is proposed the design requires the solution of another set of pdes which are shown to be solvable in several practical examples it is also proven that the full order observer with dynamic scaling recently proposed by karagiannis and astolfi obviates the need to solve the latter pdes finally it is shown that the observer can be used in conjunction with an asymptotically stabilizing full state feedback interconnection and damping assignment passivity based controller preserving asymptotic stability

adaptive control of linear time varying plants abstract in this paper the model reference adaptive control mrac problem of a class of linear time varying ltv plants is considered the plant parameters are assumed to be smooth bounded functions of time which satisfy the usual assumptions of mrac for time invariant plants at each frozen time instant it is first shown that if the plant parameters are sufficiently slowly varying with time a control parameter vector with smooth elements exists such that the closed loop plant behaves almost like a linear time invariant reference model the robust adaptive law proposed in ioannou and tsakalis 1986 ieee trans aut control ac 31 1033 is then used to adjust the controller parameters and establish boundedness of all signals in the adaptive loop for any bounded initial conditions it is shown that the bound for the residual tracking error depends on the speed of the plant parameter variations in such a way that as these parameters become constant the bound reduces to zero

multifractal behavior of the korean stock market index kospi abstract we investigate multifractality in the korean stock market index kospi the generalized qth order height height correlation function shows multiscaling properties there are two scaling regimes with a crossover time around t c 40 min we consider the original data sets and the modified data sets obtained by removing the daily jumps which occur due to the difference between the closing index and the opening index to clarify the origin of the multifractality we also smooth the data through convolution with a gaussian function after convolution we observe that the multifractality disappears in the short time scaling regime t t c but remains in the long time scaling regime t t c regardless of whether or not the daily jumps are removed we suggest that multifractality in the short time scaling regime is caused by the local fluctuations of the stock index but the multifractality in the long time scaling regime appears to be due to the intrinsic trading properties such as herding behavior information outside the market the long memory of the volatility and the nonlinear dynamics of the stock market

bipolar semicopulas the concept of semicopula plays a fundamental role in the aggregation theory on interval 0 1 semicopulas are applied for example in the definition of universal integrals we present an extension of the notion of semicopula to the case of symmetric bipolar interval 1 1 we call this extension bipolar semicopula the last definition can be used to obtain a simplified definition of the bipolar universal integral moreover bipolar semicopulas allow for an extension of theory of quasi copulas to the interval 1 1

energy dissipating hybrid control for impulsive dynamical systems abstract a novel class of fixed order energy based hybrid controllers is proposed as a means for achieving enhanced energy dissipation in nonsmooth euler lagrange hybrid port controlled hamiltonian and lossless impulsive dynamical systems these dynamic controllers combine a logical switching architecture with hybrid dynamics to guarantee that the system plant energy is strictly decreasing across switchings the general framework leads to hybrid closed loop systems described by impulsive differential equations special cases of energy based hybrid controllers involving state dependent switching are described and an illustrative numerical example is given to demonstrate the efficacy of the proposed approach

on stolarsky inequality for sugeno and choquet integrals recently flores franulic roman flores and chalco cano proved the stolarsky type inequality for sugeno integral with respect to the lebesgue measure l the present paper is devoted to generalize this result by relaxing some of its requirements moreover stolarsky inequality for choquet integral is added too

observers are unnecessary for output feedback control of lagrangian systems we address and solve some long standing yet well documented open problems on output feedback tracking control of euler lagrange systems with arbitrarily high relative degree this includes underactuated systems our main contribution is to establish a theoretical foundation for the use of so called dirty derivatives a common ad hoc replacement of unavailable state measurements such as generalized velocities whence obviating the the use of observers for the purpose of position feedback tracking control reminiscent of passivity based control for robot manipulators our control law is globally lipschitz and the controller dynamics is linear for relative degree two fully actuated lagrangian systems without dissipative forces friction and with bounded inertia matrix we establish uniform global asymptotic stability in closed loop furthermore we show that our control approach applies to lagrangian systems augmented by a chain of integrators relative degree m 2 systems the design method which is based on a recursive procedure in the spirit of backstepping control is intuitive as it exploits structural properties such as passivity and inherent input output stability as a corollary we solve an output feedback global tracking control problem for flexible joint robots but also for systems coupled with output feedback linearizable actuator dynamics in addition we discuss remaining open problems of fairly general interest in the realm of analysis and design of robust nonlinear systems

extended triangular norms the paper is devoted to classical t norms extended to operations on fuzzy quantities in accordance with the generalized zadeh extension principle such extended t norms are used for calculating intersection of type 2 fuzzy sets analytical expressions for membership functions of some extended t norms are derived assuming special classes of fuzzy quantities i e fuzzy truth intervals or fuzzy truth numbers the possibility of applying these results in the construction of type 2 adaptive network fuzzy inference systems is illustrated on several examples

adaptive sliding mode control of nonlinear robotic systems with time varying parameters abstract in this paper an adaptive sliding mode control scheme is presented for nonlinear robotic systems with bounded time varying parameters the control scheme developed is very simple and computationally efficient since it does not require a knowledge of either the mathematical model or the parameter values of the robotic dynamics it is shown that the controller is globally stable in the presence of a class of state dependent uncertainties and that the size of the tracking error can be made arbitrarily small

brief paper a globally exponentially convergent immersion and invariance speed observer for mechanical systems with non holonomic constraints the problem of velocity estimation for general n degrees of freedom mechanical systems is of great practical and theoretical interest for unconstrained systems many partial solutions have been reported in the literature however even in this case the basic question of whether it is possible to design a globally convergent speed observer remains open in this paper an affirmative answer to the question is given for general mechanical systems with knon holonomic constraints by proving the existence of a 3n 2k 1 dimensional globally exponentially convergent speed observer an observer for unconstrained mechanical systems is obtained as a particular case of this general result instrumental for the construction of the speed observer is the use of the immersion and invariance technique in which the observer design problem is recast as a problem of rendering attractive and invariant a manifold defined in the extended state space of the plant and the observer

a universal integral as common frame for choquet and sugeno integral the choquet and the sugeno integral provide a useful tool in many problems in engineering and social choice where the aggregation of data is required however their applicability is restricted because of the special operations used in the construction of these integrals therefore we provide a concept of integrals generalizing both the choquet and the sugeno case for functions with values in the nonnegative real numbers universal integrals are introduced and investigated which can be defined on arbitrary measurable spaces and for arbitrary monotone measures for a fixed pseudo multiplication on the nonnegative real numbers the smallest and the greatest universal integrals are given finally another construction method for obtaining universal integrals is introduced and the restriction to the unit interval i e to fuzzy integrals is considered

weak convergence of nonadditive measures based on nonlinear integral functionals abstract in this paper we formulate a general portmanteau theorem for a perturbative nonlinear integral functional and discuss the uniformity of weak convergence of nonadditive measures based on such a functional as their direct consequences it turns out that levy convergence of nonadditive measures coincides with every one of three types of weak convergence that is weak choquet weak sugeno and weak shilkret convergence and they are uniform on every bounded subset of lipschitz functions those results are applied when discussing the metrizability of the levy topology on the space of nonadditive measures and defining the fortet mourier type metrics on a uniformly equi autocontinuous set of nonadditive measures

jensen type inequality for the bipolar pseudo integrals abstract the main purpose of this paper is to establish conditions under which the jensen type inequality for the discrete bipolar pseudo integral is valid besides we extend investigations of the properties of the bipolar pseudo integral the observations concern the discrete bipolar pseudo integrals based on the following three canonical cases of two binary symmetric operations in the first case they are generated by an odd strictly increasing and continuous function in the remaining two cases a symmetric addition is the symmetric maximum while in the second case the corresponding pseudo multiplication is a non idempotent operation and in the third case it is the symmetric minimum

observer design for unilaterally constrained lagrangian systems a passivity based approach this paper addresses the problem of state estimation in nonlinear lagrangian dynamical systems with frictionless unilateral constraints using the position measurement as output the discontinuous velocity variable in such systems is modeled as a function of bounded variation so that zeno phenomenon is not ruled out since the derivative of such functions is represented with the lebesgue stieltjes measure the framework of measure differential inclusions mdis is used to describe the dynamics a class of estimators is proposed which also uses the framework of mdis and is shown to generate asymptotically converging state estimates the existence and uniqueness of solutions for the proposed estimators is rigorously proven the global stability of error dynamics is analyzed using the generalized lyapunov methods for functions of bounded variation as particular cases of our estimators we provide an explicit construction of a full order observer and a reduced order observer

impulsive practical tracking synchronization of networked uncertain lagrangian systems without and with time delays abstract this paper presents a procedure for studying tracking synchronization of networked lagrangian systems via impulsive control where each agent is allowed to be nonidentical even uncertain dynamics some algebraic criteria for tracking synchronization without and with time delays are established respectively it turns out that these criteria can provide a novel impulsive control strategy to synchronize globally networked lagrangian systems to a given time varying target trajectory with a desired tracking error bound called as practical tracking synchronization a distinctive feature of the developed control strategy is fully to take into account the effects of impulsive constraints and thereby to yield impulsive synchronization motion of networked lagrangian systems provided that each agent instantaneously interacts with its neighbors only at some discrete moments as a direct application of the theoretical results practical tracking synchronization of nonidentical 3 dof mobile robots without and with time delays is discussed in detail simulation results illustrate and visualize the effectiveness and feasibility of the proposed control technique