Recent zbMATH articles in MSC 93https://www.zbmath.org/atom/cc/932021-04-16T16:22:00+00:00WerkzeugSecond-order necessary optimality conditions for a discrete optimal control problem.https://www.zbmath.org/1456.490212021-04-16T16:22:00+00:00"Toan, N. T."https://www.zbmath.org/authors/?q=ai:nguyen-thi-toan."Ansari, Q. H."https://www.zbmath.org/authors/?q=ai:ansari.qamrul-hasan"Yao, J.-C."https://www.zbmath.org/authors/?q=ai:yao.jen-chihSummary: In this paper, we study second-order necessary optimality conditions for a discrete optimal control problem with a nonconvex cost function and control constraints. By establishing an abstract result on second-order necessary optimality conditions for a mathematical programming problem, we derive second-order optimality conditions for a discrete optimal control problem.Forward controllability of a random attractor for the non-autonomous stochastic sine-Gordon equation on an unbounded domain.https://www.zbmath.org/1456.350432021-04-16T16:22:00+00:00"Yang, Shuang"https://www.zbmath.org/authors/?q=ai:yang.shuang"Li, Yangrong"https://www.zbmath.org/authors/?q=ai:li.yangrongSummary: A pullback random attractor is called forward controllable if its time-component is semi-continuous to a compact set in the future, and the minimum among all such compact limit-sets is called a forward controller. The existence of a forward controller closely relates to the forward compactness of the attractor, which is further argued by the forward-pullback asymptotic compactness of the system. The abstract results are applied to the non-autonomous stochastic sine-Gordon equation on an unbounded domain. The existence of a forward compact attractor is proved, which leads to the existence of a forward controller. The measurability of the attractor is proved by considering two different universes.Asymptotic analysis of unstable solutions of stochastic differential equations.https://www.zbmath.org/1456.600022021-04-16T16:22:00+00:00"Kulinich, Grigorij"https://www.zbmath.org/authors/?q=ai:kulinich.grigorii-l"Kushnirenko, Svitlana"https://www.zbmath.org/authors/?q=ai:kushnirenko.svitlana-v"Mishura, Yuliya"https://www.zbmath.org/authors/?q=ai:mishura.yuliya-sSDEs (stochastic differential equations) is one of the main topics of modern probability theory and its applications. Usually we deal with a stochastic process, say \(X_t, \ t \geq 0\), obtained as a solution of a specific SDE and derive a series of `nice' properties of its distributions and trajectories. One of the fundamental questions of interest is: \ what is \ \(\lim_{t \to \infty}X_t.\) There are many results showing that, under appropriate conditions, \(\lim_{t \to \infty}X_t\) tends to zero, or belongs to a bounded domain in which case we say that the solution \(X_t, \ t \geq 0\) is stable. Of course, the stability property is specified in any concrete case.
Thus, if the SDE is such that in one or another sense the limit \(\lim_{t \to \infty}X_t\) is unbounded, we say the solution
\(X_t, t \geq 0\) is unstable. Studying unstable SDEs is not less important and not easier to deal with than studying stable SDEs. The present book is the first systematic account of most models, problems, results and ideas available in the literature.
One of the co-authors, Prof. G. Kulinich was the first who started studying unstable SDEs. The topic was suggested
to him by A.V. Skorokhod in 1965.
The material is well structured and distributed in six chapters. The main goal is to analyze appropriate integral functionals of unstable stochastic processes related to diverse sort of SDEs and establish limit theorems. The Brownian motion and Itô type of SDEs are essentially involved. A large number of results with specified kind of convergence is presented together with their proofs and illustrative examples. The limiting objects always have a simple structure, e.g., a constant, a proper random variable or a specific `easier' stochastic process. All limits are described in detail. Thus, to start with an unstable stochastic process and transform it into something easier and tractable is a successful way of a `domestication' of unstable stochastic processes. Important is to see `domesticated' limiting objects, all easy to work with.
The book ends with an appendix containing basic notions and results used intensively in the text and references of
both theoretical and applied nature. There is no index.
Besides their theoretical value, many of the results in this book are related to specific practical problems.
Specific indications are given in the text.
Some ideas and techniques exploited here can eventually be used or extended for studying other classes of
unstable stochastic processes.
The book will be of interest to anybody working in stochastic analysis and its applications, from master and PhD students
to professional researchers. Applied scientists can also benefit from this book by seeing efficient methods to
deal with unstable processes.
Reviewer: Jordan M. Stoyanov (Sofia)Non-equilibrium equalities with unital quantum channels.https://www.zbmath.org/1456.812842021-04-16T16:22:00+00:00"Rastegin, Alexey E."https://www.zbmath.org/authors/?q=ai:rastegin.alexey-eOptimal Petri net supervisor synthesis for forbidden state problems using marking mask.https://www.zbmath.org/1456.930052021-04-16T16:22:00+00:00"Li, Yuting"https://www.zbmath.org/authors/?q=ai:li.yuting"Yin, Li"https://www.zbmath.org/authors/?q=ai:yin.li"Chen, Yufeng"https://www.zbmath.org/authors/?q=ai:chen.yufeng"Yu, Zhenhua"https://www.zbmath.org/authors/?q=ai:yu.zhenhua"Wu, Naiqi"https://www.zbmath.org/authors/?q=ai:wu.naiqiSummary: This article addresses the forbidden state problem in discrete-event systems (DESs) modeled with Petri nets. Given a control specification, we first decide the sets of forbidden and admissible markings. Then, the minimal mask set of first-met forbidden markings (FFMs) and the minimal root set of admissible markings are computed by marking mask that is implemented using a class of special places in a plant, called competitive places. Marking mask can effectively filtrate the markings to be processed such that the two obtained sets are in general much smaller than the sets of originally specified forbidden and admissible markings, respectively. Monitors computed by place invariants are used to forbid the forbidden markings. It is shown that a maximally permissive (optimal) supervisor can be computed if it exists. Integer linear programming is used to optimize the structure of a supervisor. The minimal mask set of FFMs and root set of admissible markings efficiently reduce the computational overhead because of much fewer constraints and variables in the formulated programming problem. The developed methodology is illustrated by parameterized examples.Nonconvex policy search using variational inequalities.https://www.zbmath.org/1456.681732021-04-16T16:22:00+00:00"Zhan, Yusen"https://www.zbmath.org/authors/?q=ai:zhan.yusen"Ammar, Haitham Bou"https://www.zbmath.org/authors/?q=ai:ammar.haitham-bou"Taylor, Matthew E."https://www.zbmath.org/authors/?q=ai:taylor.matthew-eSummary: Policy search is a class of reinforcement learning algorithms for finding optimal policies in control problems with limited feedback. These methods have been shown to be successful in high-dimensional problems such as robotics control. Though successful, current methods can lead to unsafe policy parameters that potentially could damage hardware units. Motivated by such constraints, we propose projection-based methods for safe policies.
These methods, however, can handle only convex policy constraints. In this letter, we propose the first safe policy search reinforcement learner capable of operating under nonconvex policy constraints. This is achieved by observing, for the first time, a connection between nonconvex variational inequalities and policy search problems. We provide two algorithms, Mann and two-step iteration, to solve the above problems and prove convergence in the nonconvex stochastic setting. Finally, we demonstrate the performance of the algorithms on six benchmark dynamical systems and show that our new method is capable of outperforming previous methods under a variety of settings.Supervisory control and scheduling of resource allocation systems. Reachability graph perspective.https://www.zbmath.org/1456.930012021-04-16T16:22:00+00:00"Huang, Bo"https://www.zbmath.org/authors/?q=ai:huang.bo"Zhou, MengChu"https://www.zbmath.org/authors/?q=ai:zhou.mengchuPublisher's description: The book offers an important guide to Petri net (PN) models and methods for supervisory control and system scheduling of resource allocation systems (RASs). Resource allocation systems are common in automated manufacturing systems, project management systems, cloud data centers, and software engineering systems. The authors -- two experts on the topic -- present a definition, techniques, models, and state-of-the art applications of supervisory control and scheduling problems.
The book introduces the basic concepts and research background on resource allocation systems and Petri nets. The authors then focus on the deadlock-free supervisor synthesis for RASs using Petri nets. The book also investigates the heuristic scheduling of RASs based on timed Petri nets. Conclusions and open problems are provided in the last section of the book.
This important book:
\begin {itemize}
\item Includes multiple methods for supervisory control and scheduling with reachability graphs, and provides illustrative examples
\item Reveals how to accelerate the supervisory controller design and system scheduling of RASs based on PN reachability graphs, with optimal or near-optimal results
\item Highlights both solution quality and computational speed in RAS deadlock handling and system scheduling
\end {itemize}
Written for researchers, engineers, scientists, and professionals in system planning and control, engineering, operation, and management, the book provides an essential guide to the supervisory control and scheduling of resource allocation systems (RASs) using Petri net reachability graphs, which allow for multiple resource acquisitions and flexible routings.Finite-time stability for differential inclusions with applications to neural networks.https://www.zbmath.org/1456.340162021-04-16T16:22:00+00:00"Matusik, Radosław"https://www.zbmath.org/authors/?q=ai:matusik.radoslaw"Nowakowski, Andrzej"https://www.zbmath.org/authors/?q=ai:nowakowski.andrzej-f"Plaskacz, Sławomir"https://www.zbmath.org/authors/?q=ai:plaskacz.slawomir"Rogowski, Andrzej"https://www.zbmath.org/authors/?q=ai:rogowski.andrzejThe paper studies differential inclusions of the form
\[
x'\in F(t,x),
\]
where \(F:[0,\infty )\times\mathbb{R}^n\to \mathcal{P}(\mathbb{R}^n)\) is a set-valued map with non-empty compact convex values. It is assumed that \(F(t,.)\) is upper semicontinuous, \(F\) satisfies a certain linear growth condition and that the origin is an equilibrium point (i.e, \(0\in F(t,0)\) for almost all \(t\in [0,\infty )\)).
By using a nonsmooth Lyapunov function, sufficient conditions for weak and strong finite-time stability are obtained in terms of contingent epiderivatives and hypoderivatives of the Lyapunov function.
An application to a class of Hopfield neural networks is also provided.
Reviewer: Aurelian Cernea (Bucharest)A phasor analysis method for charge-controlled memory elements.https://www.zbmath.org/1456.780012021-04-16T16:22:00+00:00"Guo, Zhang"https://www.zbmath.org/authors/?q=ai:guo.zhang"Iu, Herbert H. C."https://www.zbmath.org/authors/?q=ai:iu.herbert-ho-ching"Si, Gangquan"https://www.zbmath.org/authors/?q=ai:si.gangquan"Xu, Xiang"https://www.zbmath.org/authors/?q=ai:xu.xiang"Oresanya, Babajide Oluwatosin"https://www.zbmath.org/authors/?q=ai:oresanya.babajide-oluwatosin"Bie, Yiyuan"https://www.zbmath.org/authors/?q=ai:bie.yiyuanThe authors describe a phasor analysis method to understand memory elements in circuits. These elements include memristors, memcapacitors, and meminductors. This method is a unified way to calculate memory elements within a circuit by introducing one variable \(\dot{Z}_M\). Some typical phenomenon are also discussed by the authors; four situations in particular are addressed with the proposed method.
Reviewer: Eric Stachura (Marietta)General energy decay for a degenerate viscoelastic Petrovsky-type plate equation with boundary feedback.https://www.zbmath.org/1456.350352021-04-16T16:22:00+00:00"Li, Fushan"https://www.zbmath.org/authors/?q=ai:li.fushan"Du, Guangwei"https://www.zbmath.org/authors/?q=ai:du.guangweiSummary: In this paper, we consider a degenerate viscoelastic Petrovsky-type plate equation
\[K(\boldsymbol{x})u_{tt}+\Delta^2u-\int_0^tg(t-s)\Delta^2u(s)ds+f(u)=0\]
with boundary feedback. Under the weaker assumption on the relaxation function, the general energy decay is proved by priori estimates and analysis of Lyapunov-like functional. The exponential decay result and polynomial decay result in some literature are special cases of this paper.Perturbation analysis of rational Riccati equations.https://www.zbmath.org/1456.150152021-04-16T16:22:00+00:00"Weng, Peter Chang-Yi"https://www.zbmath.org/authors/?q=ai:weng.peter-chang-yiSummary: In this paper, we consider the perturbation analyses of the continuous-time rational Riccati equations using the norm-wise, mixed and component-wise analyses, which arises from the stochastic \(H_\infty\) problems and the indefinite stochastic linear quadratic control problems. We derive sufficient conditions for the existence of stabilizing solutions of the perturbed rational Riccati equations. Moreover, we obtain the perturbation bounds for the relative errors with respect to the stabilizing solutions of the rational Riccati equations under three kinds of perturbation analyses. Numerical results are presented to illustrate sharper perturbation bounds under the normwise, mixed and componentwise perturbation analyses.The generalized TAP free energy. II.https://www.zbmath.org/1456.827622021-04-16T16:22:00+00:00"Chen, Wei-Kuo"https://www.zbmath.org/authors/?q=ai:chen.wei-kuo"Panchenko, Dmitry"https://www.zbmath.org/authors/?q=ai:panchenko.dmitry"Subag, Eliran"https://www.zbmath.org/authors/?q=ai:subag.eliranSummary: In a recent paper [the authors, ``The generalized TAP free energy'', Comm. Pure Appl. Math. (to appear), \url{arXiv:1812.05066}], we developed the generalized TAP approach for mixed \(p\)-spin models with Ising spins at positive temperature. Here we extend these results in two directions. We find a simplified representation for the energy of the generalized TAP states in terms of the Parisi measure of the model and, in particular, show that the energy of all states at a given distance from the origin is the same. Furthermore, we prove the analogues of the positive temperature results at zero temperature, which concern the ground-state energy and the organization of ground-state configurations in space.An improved algorithm for generalized least squares estimation.https://www.zbmath.org/1456.621392021-04-16T16:22:00+00:00"Chang, Xiao-Wen"https://www.zbmath.org/authors/?q=ai:chang.xiaowen"Titley-Peloquin, David"https://www.zbmath.org/authors/?q=ai:titley-peloquin.davidSummary: The textbook direct method for generalized least squares estimation was developed by \textit{C. C. Paige} [Math. Comput. 33, 171--183 (1979; Zbl 0405.65018); SIAM J. Numer. Anal. 16, 165--171 (1979; Zbl 0402.65006)] about 40 years ago. He proposed two algorithms. Suppose that the noise covariance matrix, rather than its factor, is available. Both of the Paige's algorithms involve three matrix factorizations. The first does not exploit the matrix structure of the problem, but it can be implemented by blocking techniques to reduce data communication time on modern computer processors. The second takes advantage of the matrix structure, but its main part cannot be implemented by blocking techniques. In this paper, we propose an improved algorithm. The new algorithm involves only two matrix factorizations, instead of three, and can be implemented by blocking techniques. We show that, in terms of flop counts, the improved algorithm costs less than Paige's first algorithm in any case and less than his second algorithm in some cases. Numerical tests show that in terms of CPU running time, our improved algorithm is faster than both of the existing algorithms when blocking techniques are used.Bogolyubov's theorem for a controlled system related to a variational inequality.https://www.zbmath.org/1456.490152021-04-16T16:22:00+00:00"Tolstonogov, A. A."https://www.zbmath.org/authors/?q=ai:tolstonogov.alexander-aA compact form dynamics controller for a high-DOF tetrapod-on-wheel robot with one manipulator via null space based convex optimization and compatible impedance controllers.https://www.zbmath.org/1456.700212021-04-16T16:22:00+00:00"Du, Wenqian"https://www.zbmath.org/authors/?q=ai:du.wenqian"Benamar, Faïz"https://www.zbmath.org/authors/?q=ai:benamar.faizSummary: This paper develops a compact form dynamics controller to generate multi-compliant behaviors for a new designed tetrapod-on-wheel robot with one manipulator. The whole-body compliant torque controller is stated through one null-space-based convex optimization and compatible null-space-based impedance controllers. Different from fixed contact points of conventional quadruped robots, the kinematic wheel contact constraints are derived for our legged-on-wheel robot, which serves as the basis for each task reference extraction and each compliance controller. The compact relationships between task references and optimization control variables are extracted using null-space-based inverse dynamics, which is used to build the cost function in the operational space and/or in the joint space. The whole-body control frame is developed and several null-space-based feed-back impedance controllers are integrated into the compact relationships to allow the robot to achieve compliance and compensate the model impreciseness, especially the wheel contact model. Then the detailed algorithm is presented whose output combines the feed-forward and feedback torque. The validation of our approach is performed via advanced numerical simulations for a virtual legged-on-wheel robot with one manipulator.Exit time asymptotics for dynamical systems with fast random switching near an unstable equilibrium.https://www.zbmath.org/1456.601392021-04-16T16:22:00+00:00"Bakhtin, Yuri"https://www.zbmath.org/authors/?q=ai:bakhtin.yuri-yu"Gaál, Alexisz"https://www.zbmath.org/authors/?q=ai:gaal.alexisz-tamasA data-driven McMillan degree lower bound.https://www.zbmath.org/1456.370982021-04-16T16:22:00+00:00"Hokanson, Jeffrey M."https://www.zbmath.org/authors/?q=ai:hokanson.jeffrey-mSpatio-temporal dependence measures for bivariate AR(1) models with \(\alpha \)-stable noise.https://www.zbmath.org/1456.621902021-04-16T16:22:00+00:00"Grzesiek, Aleksandra"https://www.zbmath.org/authors/?q=ai:grzesiek.aleksandra"Sikora, Grzegorz"https://www.zbmath.org/authors/?q=ai:sikora.grzegorz"Teuerle, Marek"https://www.zbmath.org/authors/?q=ai:teuerle.marek-a"Wyłomańska, Agnieszka"https://www.zbmath.org/authors/?q=ai:wylomanska.agnieszkaThe authors investigate properties of the \(\alpha\)-stable bidimensional
vector autoregressive VAR(1) model described by the equation
\[
X (t) -\Theta X (t - 1) = Z (t) ,
\] where the noise \(\{Z (t)\}\)
is an \(\alpha\)-stable vector in \(\mathbb R^2\) with the stability index \(\alpha<2\)
called \(\alpha\)-stable noise (or an infinite-variance noise).
Under the condition that all the eigenvalues of the matrix \(\Theta\) are less than 1 in absolute value, which is equivalent to
\(\det(I - z\Theta)\not= 0\) for all \(\{z:|z|\leq 1\}\),
the defined by such an equation time series \(\{X (t)\}\) can be written in causal representation
\[
X(t) =\sum_{j=0}^{\infty}(\Theta)^jZ (t - j)
\]
In the case of (Gaussian) white noise \(\{Z (t)\}\) the spatio-temporal dependence structure of the bidimensional time series the cross-covariation is applied to describe properties of the time series. The cross-covariance has found many applications in time series investigation, especially in signal processing.
However, the cross-covariance is not an appropriate measure for the \(\alpha\)-stable stochastic processes where the second moment is infinite and therefore the theoretical function does not exist.
Then, for stochastic processes with infinite variance, the alternative measures should be applied.
In this article the authors propose the cross-codifference and the cross-covariation functions which are the analogues of the classical cross-covariance for infinite variance processes.
They provide theoretical results for cross-codifference and cross-covariation bidimensional VAR(1) time series with \(\alpha\)-stable i.i.d. noise and demonstrate that cross-codifference and cross-covariation can give different useful information about the relationships between components of bidimensional VAR models.
This article is an extension of the authors previous work (see [``Cross-codifference for bidimensional VAR(1) time series with infinite variance'', Comm. Stat. (to appear)]) where the cross-codifference was considered as the spatio-temporal measure of the components of VAR model based on sub-Gaussian distribution.
Reviewer: Mikhail P. Moklyachuk (Kyïv)Online algorithm for variance components estimation.https://www.zbmath.org/1456.860102021-04-16T16:22:00+00:00"Zhang, Xinggang"https://www.zbmath.org/authors/?q=ai:zhang.xinggang"Lu, Xiaochun"https://www.zbmath.org/authors/?q=ai:lu.xiaochunSummary: In this study, we develop a new algorithm for online variance components estimation (Online-VCE) of geodetic data based on the batch expectation-maximization (EM) algorithm and stochastic approximation theory. The Online-VCE algorithm is then applied to the Kalman filter and least-squares method and validated using simulated kinematic precise point positioning (PPP) based on the global navigation satellite system as well as real-data PPP experiments. The Online-VCE algorithm is specifically designed to monitor and establish a stochastic model in real-time or high-rate data applications. Compared to other methods, the Online-VCE is faster and can estimate the stochastic model in real time because it does not need to store all data, but simply estimates the expected result and computes the gradient of the parameters using only one or a few observations. In future, the Online-VCE algorithm can be used to develop a real-time atmospheric stochastic model for PPP applications.Practical methods to investigate observability of linear time-varying systems.https://www.zbmath.org/1456.930042021-04-16T16:22:00+00:00"Morozov, V. M."https://www.zbmath.org/authors/?q=ai:morozov.victor-m"Baklanov, F. Yu."https://www.zbmath.org/authors/?q=ai:baklanov.f-yuSummary: The work proposes a practical methodology to investigate observability of linear time-varying systems. The methodology comprises analytical and numerical methods, as well as a technique to verify results of analytical investigation numerically. Employing reducibility in the analysis of observability is demonstrated.Advances in stabilization of hybrid stochastic differential equations by delay feedback control.https://www.zbmath.org/1456.601482021-04-16T16:22:00+00:00"Hu, Junhao"https://www.zbmath.org/authors/?q=ai:hu.junhao"Liu, Wei"https://www.zbmath.org/authors/?q=ai:liu.wei"Deng, Feiqi"https://www.zbmath.org/authors/?q=ai:deng.feiqi"Mao, Xuerong"https://www.zbmath.org/authors/?q=ai:mao.xuerongStructural equation modeling. Applications using Mplus. 2nd edition.https://www.zbmath.org/1456.620092021-04-16T16:22:00+00:00"Wang, Jichuan"https://www.zbmath.org/authors/?q=ai:wang.jichuan"Wang, Xiaoqian"https://www.zbmath.org/authors/?q=ai:wang.xiaoqianPublisher's description: Focusing on the conceptual and practical aspects of Structural Equation Modeling (SEM), this book demonstrates basic concepts and examples of various SEM models, along with updates on many advanced methods, including confirmatory factor analysis (CFA) with categorical items, bifactor model, Bayesian CFA model, item response theory (IRT) model, graded response model (GRM), multiple imputation (MI) of missing values, plausible values of latent variables, moderated mediation model, Bayesian SEM, latent growth modeling (LGM) with individually varying times of observations, dynamic structural equation modeling (DSEM), residual dynamic structural equation modeling (RDSEM), testing measurement invariance of instrument with categorical variables, longitudinal latent class analysis (LLCA), latent transition analysis (LTA), growth mixture modeling (GMM) with covariates and distal outcome, manual implementation of the BCH method and the three-step method for mixture modeling, Monte Carlo simulation power analysis for various SEM models, and estimate sample size for latent class analysis (LCA) model.
The statistical modeling program Mplus Version 8.2 is featured with all models updated. It provides researchers with a flexible tool that allows them to analyze data with an easy-to-use interface and graphical displays of data and analysis results.
Intended as both a teaching resource and a reference guide, and written in non-mathematical terms, Structural Equation Modeling: Applications Using Mplus, 2nd edition provides step-by-step instructions of model specification, estimation, evaluation, and modification. Chapters cover: Confirmatory Factor Analysis (CFA); Structural Equation Models (SEM); SEM for Longitudinal Data; Multi-Group Models; Mixture Models; and Power Analysis and Sample Size Estimate for SEM.
\begin {itemize}
\item Presents a useful reference guide for applications of SEM while systematically demonstrating various advanced SEM models
\item Discusses and demonstrates various SEM models using both cross-sectional and longitudinal data with both continuous and categorical outcomes
\item Provides step-by-step instructions of model specification and estimation, as well as detailed interpretation of Mplus results using real data sets
\item Introduces different methods for sample size estimate and statistical power analysis for SEM
\end {itemize}
Structural Equation Modeling is an excellent book for researchers and graduate students of SEM who want to understand the theory and learn how to build their own SEM models using Mplus.Variational and optimal control representations of conditioned and driven processes.https://www.zbmath.org/1456.930072021-04-16T16:22:00+00:00"Chetrite, Raphaël"https://www.zbmath.org/authors/?q=ai:chetrite.raphael"Touchette, Hugo"https://www.zbmath.org/authors/?q=ai:touchette.hugoLaplacian controllability for graphs with integral Laplacian spectrum.https://www.zbmath.org/1456.051092021-04-16T16:22:00+00:00"Stanić, Zoran"https://www.zbmath.org/authors/?q=ai:stanic.zoranSummary: If \(G\) is a graph with \(n\) vertices, \(L_G\) is its Laplacian matrix, and \(\mathfrak{b}\) is a binary vector of length \(n\), then the pair \((L_G, \mathfrak{b})\) is said to be controllable, and we also say that \(G\) is Laplacian controllable for \(\mathfrak{b}\), if \(\mathfrak{b}\) is non-orthogonal to any of the eigenvectors of \(L_G\). It is known that if \(G\) is Laplacian controllable, then it has no repeated Laplacian eigenvalues. If \(G\) has no repeated Laplacian eigenvalues and each of them is an integer, then \(G\) is decomposable into a (dominate) induced subgraph, say \(H\), and another induced subgraph with at most three vertices. We express the Laplacian controllability of \(G\) in terms of that of \(H\). In this way, we address the question on the Laplacian controllability of cographs and, in particular, threshold graphs.Designing continuous delay feedback control for lattice hydrodynamic model under cyber-attacks and connected vehicle environment.https://www.zbmath.org/1456.826352021-04-16T16:22:00+00:00"Zhai, Cong"https://www.zbmath.org/authors/?q=ai:zhai.cong"Wu, Weitiao"https://www.zbmath.org/authors/?q=ai:wu.weitiaoSummary: The rapid adoption of sensors has improved the communication capacity of vehicles, while connected vehicles are expected to become commercially available in the near future. In a connected vehicle environment, the dynamic continuous kinetic information on roadway could be readily available through sensors and internet of vehicular technologies. Nevertheless, in practice the vehicular networks may suffer from cyber-attacks, such that the perceived traffic data can deviate from the actual situation. Such potential risks may greatly worsen traffic condition. There is increasing need for developing a framework to control traffic flow effectively using continuous traffic information under cyber-attacks and connected vehicle environment. In this study, we propose an extended lattice model incorporating not only multiple connected vehicles but also the continuous delay feedback control signals. The stability condition is obtained based on the Hurwitz criteria and the \(H_\infty \)- norm. We further devise a continuous delay feedback controller to regularize the propagation of the enhanced lattice model in the case when the stability condition is not satisfied. The Bode-plot of transfer function shows that the stability region enhances with the continuous delayed feedback controller. We study how far ahead information about the downstream lattices should be integrated into the control process. Results show that the continuous traffic information and the controller contribute to mitigating traffic jam.Inference for asymmetric exponentially weighted moving average models.https://www.zbmath.org/1456.622052021-04-16T16:22:00+00:00"Li, Dong"https://www.zbmath.org/authors/?q=ai:li.dong.2"Zhu, Ke"https://www.zbmath.org/authors/?q=ai:zhu.keFinancial markets are not perfect and the risk cannot be totally eliminated.
The most commonly used tool for risk measure is Value at Risk. It shows the maximum loss in the value of a portfolio asset.
The first comprehensive market risk management methodology was developed by J. P. Morgan in 1994 (see J. P. Morgan and Reuters, RiskMetrics\(^{TM}\) -- Technical Document, a set of techniques and data to measure market risks in portfolios of fixed income instruments, equities, foreign exchange, commodities, and their derivatives issued in over 30 countries. This edition has been expanded significantly from the previous release issued in May 1995. \url{http://www.jpmorgan.com/RiskManagement/RiskMetrics/RiskMetrics.html})
and was called RiskMetrics\(^{TM}\), which become extremely popular due to its easy implementation.
The exponentially weighted moving average (EWMA) model has
been a benchmark for controlling and forecasting risks in financial operations.
It is defined by relations
\[
y_t = \eta_t\sqrt{h_t},\quad h_t = \alpha_0y^2_{ t-1} + \beta_0h_{t-1},
\]
where the initial values \(y_0\in\mathbb R\) and \(h_0 \geq0\), parameters \(\alpha_0 > 0\), \(\beta_0\geq 0\), and \(\{\eta_t\}\) is a sequence of i.i.d. Gaussian \((0, 1)\) innovations.
The statistical inference procedure for this model was developed by \textit{D. Li} et al. [J. Econom. 202, No. 1, 1--17 (2018; Zbl 1378.62076)].
Many empirical studies show that the asymmetric volatility effect and the heavy-tailed innovation are two important features of financial returns, while the EWMA model does not fit these two features.
Motivated by this, the authors propose a new asymmetric EWMA model described by the equations
\[
y_t = \eta_t\sqrt{h_t},\quad h_t = \alpha_{0+}(y^+_{ t-1})^2 +
\alpha_{0-}(y^-_{ t-1})^2
+ \beta_0h_{t-1},
\]
where the initial values \(y_0\in\mathbb R\) and \(h_0 \geq0\),
parameters \(\alpha_{0+} > 0\), \(\alpha_{0-} > 0\), \(\beta_0\geq 0\), and \(\{\eta_t\}\) is a sequence of i.i.d. Student's \(t_{v}\)-distributed innovations with the degree of freedom \(v>2\).
The authors study the asymptotic properties of the maximum likelihood estimator (MLE) of the unknown parameters \((\alpha_{0+},\alpha_{0-},\beta_0,v)\)
of the model and develop a Kolmogorov-type diagnostic test for the fitted distribution.
The finite-sample performance of the MLE and diagnostic test statistic is examined by the simulated data.
Reviewer: Mikhail P. Moklyachuk (Kyïv)Finite difference methods for the Hamilton-Jacobi-Bellman equations arising in regime switching utility maximization.https://www.zbmath.org/1456.650042021-04-16T16:22:00+00:00"Ma, Jingtang"https://www.zbmath.org/authors/?q=ai:ma.jingtang"Ma, Jianjun"https://www.zbmath.org/authors/?q=ai:ma.jianjunSummary: For solving the regime switching utility maximization, \textit{J. Fu} et al. [Eur. J. Oper. Res. 233, No. 1, 184--192 (2014; Zbl 1339.91108)] derive a framework that reduce the coupled Hamilton-Jacobi-Bellman (HJB) equations into a sequence of decoupled HJB equations through introducing a functional operator. The aim of this paper is to develop the iterative finite difference methods (FDMs) with iteration policy to the sequence of decoupled HJB equations derived by Fu et al. [loc. cit.]. The convergence of the approach is proved and in the proof a number of difficulties are overcome, which are caused by the errors from the iterative FDMs and the policy iterations. Numerical comparisons are made to show that it takes less time to solve the sequence of decoupled HJB equations than the coupled ones.Model-checking precision agriculture logistics: the case of the differential harvest.https://www.zbmath.org/1456.910672021-04-16T16:22:00+00:00"Saddem-yagoubi, Rim"https://www.zbmath.org/authors/?q=ai:saddem-yagoubi.rim"Naud, Olivier"https://www.zbmath.org/authors/?q=ai:naud.olivier"Godary-dejean, Karen"https://www.zbmath.org/authors/?q=ai:godary-dejean.karen"Crestani, Didier"https://www.zbmath.org/authors/?q=ai:crestani.didierSummary: The development, in the last decades, of technologies for precision agriculture allows the acquisition of crop data with a high spatial resolution. This offers possibilities for innovative control and raises new logistics issues that may be solved using discrete event models. In vineyards, some technologies make it possible to define zones with different qualities of grapes and sort the grapes at harvest to make different vintages. In this context, the differential harvest problem (DHP) consists in finding a trajectory of the harvesting machine in the field in order to obtain at least a given quantity of higher quality grapes and minimising working time. In available literature, the DHP has been solved using constraint programming. In this paper, we investigate if it is possible to solve the DHP using the cost optimal reachability analysis feature of a model-checking tool such as UPPAAL-CORA. A model named DHP\(\_\)PTA has been designed based on the priced timed automata formalism and the UPPAAL-CORA tool. The method made it possible to obtain the optimal trajectory of a harvesting machine for a vine plot composed of up to 14 rows. The study is based on real vineyard data. This paper is an extended version of a communication presented at WODES 2018
[\textit{R. Saddem-Yagoubi} et al., ``New approach for differential harvest problem: the model checking way'', IFAC-PapersOnLine 51, No. 7, 57--63 (2018; \url{doi:10.1016/j.ifacol.2018.06.279})].Controllability and observability of cascading failure networks.https://www.zbmath.org/1456.930032021-04-16T16:22:00+00:00"Sun, Peng Gang"https://www.zbmath.org/authors/?q=ai:sun.penggang"Ma, Xiaoke"https://www.zbmath.org/authors/?q=ai:ma.xiaokeCalculating the Lyapunov exponents of a piecewise-smooth soft impacting system with a time-delayed feedback controller.https://www.zbmath.org/1456.370972021-04-16T16:22:00+00:00"Zhang, Zhi"https://www.zbmath.org/authors/?q=ai:zhang.zhi"Liu, Yang"https://www.zbmath.org/authors/?q=ai:liu.yang.8|liu.yang.21|liu.yang.23|liu.yang.3|liu.yang.9|liu.yang.19|liu.yang.20|liu.yang.6|liu.yang.12|liu.yang.11|liu.yang.2|liu.yang.17|liu.yang.4|liu.yang.15|liu.yang.1|liu.yang.5|liu.yang|liu.yang.16|liu.yang.10|liu.yang.22|liu.yang.18|liu.yang.14|liu.yang.13"Sieber, Jan"https://www.zbmath.org/authors/?q=ai:sieber.janSummary: Lyapunov exponent is a widely used tool for studying dynamical systems. When calculating Lyapunov exponents for piecewise-smooth systems with time-delayed arguments one faces a lack of continuity in the variational problem. This paper studies how to build a variational equation for the efficient construction of Jacobians along trajectories of a delayed nonsmooth system. Trajectories of a piecewise-smooth system may encounter the so-called grazing event where the trajectory approaches a discontinuity surface in the state space in a non-transversal manner. For this event we develop a grazing point estimation algorithm to ensure the accuracy of trajectories for the nonlinear and the variational equations. We show that the eigenvalues of the Jacobian matrix computed by the algorithm converge with an order consistent with the order of the numerical integration method, therefore guaranteeing the reliability of the proposed numerical method. Finally, the method is demonstrated on a periodically forced impacting oscillator under the time-delayed feedback control.Approximate controllability for semilinear second-order stochastic evolution systems with infinite delay.https://www.zbmath.org/1456.340762021-04-16T16:22:00+00:00"Su, Xiaofeng"https://www.zbmath.org/authors/?q=ai:su.xiaofeng"Fu, Xianlong"https://www.zbmath.org/authors/?q=ai:fu.xianlongSummary: In this work, we study the approximate controllability for a class of semilinear second-order stochastic evolution systems with infinite delay. The main technique is the fundamental solution theory constructed through Laplace transformation. Some sufficient conditions for the approximate controllability result is obtained via the so-called resolvent condition and cosine family of linear operators. Due to the fundamental solution theory applied, the nonlinear terms are only required to be partly uniformly bounded. Finally, an example is provided to illustrate the obtained results.Measurement of network complexity and capability in command and control system.https://www.zbmath.org/1456.900362021-04-16T16:22:00+00:00"Song, Xiao"https://www.zbmath.org/authors/?q=ai:song.xiao"Zhang, Shaoyun"https://www.zbmath.org/authors/?q=ai:zhang.shaoyun"Shi, Xuecheng"https://www.zbmath.org/authors/?q=ai:shi.xuechengSummary: A concept of complexity of the Command and Control (C2) information system is introduced and an innovative approach of measuring network complexity is proposed compared with traditional network complexity computation methods. Complexity measurements, including connectivity, collaboration and redundancy, are proposed and computed. Then the complexity-based capability is discussed and studied. Finally, two case studies of an anti-aircraft defence C2 network and partial tank division network are carried out to illustrate the computation processes of the proposed network complexity and capability.Constrained target controllability of complex networks.https://www.zbmath.org/1456.930022021-04-16T16:22:00+00:00"Guo, Wei-Feng"https://www.zbmath.org/authors/?q=ai:guo.wei-feng"Zhang, Shao-Wu"https://www.zbmath.org/authors/?q=ai:zhang.shaowu"Wei, Ze-Gang"https://www.zbmath.org/authors/?q=ai:wei.ze-gang"Zeng, Tao"https://www.zbmath.org/authors/?q=ai:zeng.tao"Liu, Fei"https://www.zbmath.org/authors/?q=ai:liu.fei.2|liu.fei.1|liu.fei"Zhang, Jingsong"https://www.zbmath.org/authors/?q=ai:zhang.jingsong"Wu, Fang-Xiang"https://www.zbmath.org/authors/?q=ai:wu.fangxiang"Chen, Luonan"https://www.zbmath.org/authors/?q=ai:chen.luonanInferring topologies via driving-based generalized synchronization of two-layer networks.https://www.zbmath.org/1456.340642021-04-16T16:22:00+00:00"Wang, Yingfei"https://www.zbmath.org/authors/?q=ai:wang.yingfei"Wu, Xiaoqun"https://www.zbmath.org/authors/?q=ai:wu.xiaoqun"Feng, Hui"https://www.zbmath.org/authors/?q=ai:feng.hui"Lu, Jun-An"https://www.zbmath.org/authors/?q=ai:lu.junan"Xu, Yuhua"https://www.zbmath.org/authors/?q=ai:xu.yuhuaAnalysis of Krylov subspace approximation to large-scale differential Riccati equations.https://www.zbmath.org/1456.650192021-04-16T16:22:00+00:00"Antti, Koskela"https://www.zbmath.org/authors/?q=ai:antti.koskela"Mena, Hermann"https://www.zbmath.org/authors/?q=ai:mena.hermannSummary: We consider a Krylov subspace approximation method for the symmetric differential Riccati equation \(\dot{X} = AX + XA^T + Q - XSX, X(0)=X_0\). The method we consider is based on projecting the large-scale equation onto a Krylov subspace spanned by the matrix \(A\) and the low-rank factors of \(X_0\) and \(Q\). We prove that the method is structure preserving in the sense that it preserves two important properties of the exact flow, namely the positivity of the exact flow and also the property of monotonicity. We provide a theoretical a priori error analysis that shows superlinear convergence of the method. Moreover, we derive an a posteriori error estimate that is shown to be effective in numerical examples.Coupled systems of linear differential-algebraic and kinetic equations with application to the mathematical modelling of muscle tissue.https://www.zbmath.org/1456.340512021-04-16T16:22:00+00:00"Plunder, Steffen"https://www.zbmath.org/authors/?q=ai:plunder.steffen"Simeon, Bernd"https://www.zbmath.org/authors/?q=ai:simeon.berndSummary: We consider a coupled system composed of a linear differential-algebraic equation (DAE) and a linear large-scale system of ordinary differential equations where the latter stands for the dynamics of numerous identical particles. Replacing the discrete particles by a kinetic equation for a particle density, we obtain in the mean-field limit the new class of partially kinetic systems.
We investigate the influence of constraints on the kinetic theory of those systems and present necessary adjustments. We adapt the mean-field limit to the DAE model and show that index reduction and the mean-field limit commute. As a main result, we prove Dobrushin's stability estimate for linear systems. The estimate implies convergence of the mean-field limit and provides a rigorous link between the particle dynamics and their kinetic description.
Our research is inspired by mathematical models for muscle tissue where the macroscopic behaviour is governed by the equations of continuum mechanics, often discretised by the finite element method, and the microscopic muscle contraction process is described by Huxley's sliding filament theory. The latter represents a kinetic equation that characterises the state of the actin-myosin bindings in the muscle filaments. Linear partially kinetic systems are a simplified version of such models, with focus on the constraints.
For the entire collection see [Zbl 1445.34004].Indirect boundary observability of semi-discrete coupled wave equations.https://www.zbmath.org/1456.650642021-04-16T16:22:00+00:00"El Akri, Abdeladim"https://www.zbmath.org/authors/?q=ai:el-akri.abdeladim"Maniar, Lahcen"https://www.zbmath.org/authors/?q=ai:maniar.lahcenSummary: This work concerns the indirect observability properties for the finite-difference space semi-discretization of the 1-d coupled wave equations with homogeneous Dirichlet boundary conditions. We assume that only one of the two components of the unknown is observed. As for a single wave equation, as well as for the direct (complete) observability of the coupled wave equations, we prove the lack of the numerical observability. However, we show that a uniform observability holds in the subspace of solutions in which the initial conditions of the observed component is generated by the low frequencies. Our main proofs use a two-level energy method at the discrete level and a Fourier decomposition of the solutions.Hybrid projective combination-combination synchronization in non-identical hyperchaotic systems using adaptive control.https://www.zbmath.org/1456.340632021-04-16T16:22:00+00:00"Khan, Ayub"https://www.zbmath.org/authors/?q=ai:khan.ayub"Chaudhary, Harindri"https://www.zbmath.org/authors/?q=ai:chaudhary.harindriSummary: In this paper, we investigate a hybrid projective combination-combination synchronization scheme among four non-identical hyperchaotic systems via adaptive control method. Based on Lyapunov stability theory, the considered approach identifies the unknown parameters and determines the asymptotic stability globally. It is observed that various synchronization techniques, for instance, chaos control problem, combination synchronization, projective synchronization, etc. turn into particular cases of combination-combination synchronization. The proposed scheme is applicable to secure communication and information processing. Finally, numerical simulations are performed to demonstrate the effectivity and correctness of the considered technique by using MATLAB.Asymptotic analysis of an advection-diffusion equation and application to boundary controllability.https://www.zbmath.org/1456.352042021-04-16T16:22:00+00:00"Amirat, Youcef"https://www.zbmath.org/authors/?q=ai:amirat.youcef-ait"Münch, Arnaud"https://www.zbmath.org/authors/?q=ai:munch.arnaudThe authors consider the advection-diffusion equation
\[
y^{\varepsilon}_t-\varepsilon y^{\varepsilon}_{xx}+My^{\varepsilon}_x=0,\quad (x,t)\in (0,1)\times(0,T),
\]
\[
y^{\varepsilon}(0,t)=v^{\varepsilon}(t),\quad y^{\varepsilon}(1,t)=0,\quad t\in (0,T),\quad (1)
\]
\[
y^{\varepsilon}(x.0)=y^{\varepsilon}_0(x)\quad x\in (0,1),
\]
where \(\varepsilon\) is the diffusion coefficient, \(M\) is the transport coefficient, \(v^{\varepsilon}\)=\(v^{\varepsilon}(t)\) is the control function, \(y^{\varepsilon}_0\) is the initial data, and \(y^{\varepsilon}=y^{\varepsilon}(x,t)\) is the associated state.
The main purpose of the article is to perform the asymptotic analysis of (1) for the case \(M>0\), assuming \(v^{\epsilon}\) fixed and satisfying compatibility conditions at the initial time \(t=0\) with the initial condition \(y^{\varepsilon}_0\) as \(x=0\).
Supposing that the initial condition does not depend on \(\varepsilon\) and that the control function \(v^{\varepsilon}\) is given in the form \(v^{\varepsilon}=\sum\limits_{k=0}^m \varepsilon^k v^k\), the authors construct the accurate asymptotic approximation \(w^{\varepsilon}\) of the solution \(y^{\varepsilon}\) by using the method of matched asymptotic expansions. The inner and outer solutions are determined by using explicit formulae, and \(w^{\varepsilon}_m\) is obtained by combining the inner and outer solutions through a process of matching. It is proved that \(w^{\varepsilon}_m\) is a regular and strong approximation of \(y^{\varepsilon}\), as \(\varepsilon \to 0^{+}\). The error estimate is obtained. The same approach is applied to the solution \(\varphi^{\varepsilon}\) of the adjoint problem
\[
-\varphi^{\varepsilon}_t-\varepsilon \varphi^{\varepsilon}_{xx}-M\varphi^{\varepsilon}_x=0,\quad (x,t)\in (0,1)\times(0,T),
\]
\[
\varphi^{\varepsilon}(0,t)=\varphi^{\varepsilon}(1,t)=0 \quad t\in (0,T)
\]
\[
\varphi^{\varepsilon}(x.T)=\varphi^{\varepsilon}_T(x)\quad x\in (0,1),
\]
where \(\varphi_T^{\varepsilon}\) is a function of the form \(\varphi^{\varepsilon}_T=\sum\limits^{m}_{k=0}\varepsilon^k\varphi^k_T\), the functions \(\varphi^0_T,\varphi^1_T,\ldots,\varphi^m_T\) being given.
The authors show that under some conditions on the functions \(v^k\) and on the initial condition \(y_0\) one can pass to the limit as \(m\to \infty\) and establish a convergence result of the sequence \((w^{\varepsilon}_m)_{(m\ge 0)}\).
Then they use the asymptotic results to discuss the controllability properties of the solution for \(T\ge 1/M\).
Reviewer: Artyom Andronov (Saransk)Bias of particle approximations to optimal filter derivative.https://www.zbmath.org/1456.930062021-04-16T16:22:00+00:00"Tadić, Vladislav Z. B."https://www.zbmath.org/authors/?q=ai:tadic.vladislav-z-b"Doucet, Arnaud"https://www.zbmath.org/authors/?q=ai:doucet.arnaudPath integrals and symmetry breaking for optimal control theory.https://www.zbmath.org/1456.490272021-04-16T16:22:00+00:00"Kappen, H. J."https://www.zbmath.org/authors/?q=ai:kappen.hilbert-jThe Aronsson equation, Lyapunov functions, and local Lipschitz regularity of the minimum time function.https://www.zbmath.org/1456.490222021-04-16T16:22:00+00:00"Soravia, Pierpaolo"https://www.zbmath.org/authors/?q=ai:soravia.pierpaoloSummary: We define and study \(C^1\)-solutions of the Aronsson equation (AE), a second order quasi linear equation. We show that such super/subsolutions make the Hamiltonian monotone on the trajectories of the closed loop Hamiltonian dynamics. We give a short, general proof that \(C^1\)-solutions are absolutely minimizing functions. We discuss how \(C^1\)-supersolutions of (AE) become special Lyapunov functions of symmetric control systems, and allow to find continuous feedbacks driving the system to a target in finite time, except on a singular manifold. A consequence is a simple proof that the corresponding minimum time function is locally Lipschitz continuous away from the singular manifold, despite classical results showing that it should only be Hölder continuous unless appropriate conditions hold. We provide two examples for Hörmander and Grushin families of vector fields where we construct \(C^1\)-solutions (even classical) explicitly.Ingham type approach for uniform observability inequality of the semi-discrete coupled wave equations.https://www.zbmath.org/1456.351312021-04-16T16:22:00+00:00"da Silva Almeida Juniór, Dilberto"https://www.zbmath.org/authors/?q=ai:da-silva-almeida.dilberto-jun"de Jesus Araujo Ramos, Anderson"https://www.zbmath.org/authors/?q=ai:de-jesus-araujo-ramos.anderson"Pantoja Fortes, Joao Carlos"https://www.zbmath.org/authors/?q=ai:pantoja-fortes.joao-carlos"de Lima Santos, Mauro"https://www.zbmath.org/authors/?q=ai:de-lima-santos.mauroSummary: This article concerns an observability inequality for a system of coupled wave equations for the continuous models as well as for the space semi-discrete finite difference approximations. For finite difference and standard finite elements methods on uniform numerical meshes it is known that a numerical pathology produces a blow-up of the constant on the observability inequality as the mesh-size \(h\) tends to zero. We identify this numerical anomaly for coupled wave equations and we prove that there exists a uniform observability inequality in a subspace of solutions generated by low frequencies. We use the Ingham type approach for getting a uniform boundary observability.Complex function theory, operator theory, Schur analysis and systems theory. A volume in honor of V. E. Katsnelson.https://www.zbmath.org/1456.001062021-04-16T16:22:00+00:00"Alpay, Daniel (ed.)"https://www.zbmath.org/authors/?q=ai:alpay.daniel"Fritzsche, Bernd (ed.)"https://www.zbmath.org/authors/?q=ai:fritzsche.bernd"Kirstein, Bernd (ed.)"https://www.zbmath.org/authors/?q=ai:kirstein.berndPublisher's description: This book is dedicated to Victor Emmanuilovich Katsnelson on the occasion of his 75th birthday and celebrates his broad mathematical interests and contributions. Victor Emmanuilovich's mathematical career has been based mainly at the Kharkov University and the Weizmann Institute. However, it also included a one-year guest professorship at Leipzig University in 1991, which led to him establishing close research contacts with the Schur analysis group in Leipzig, a collaboration that still continues today.
Reflecting these three periods in Victor Emmanuilovich's career, present and former colleagues have contributed to this book with research inspired by him and presentations on their joint work. Contributions include papers in function theory (Favorov-Golinskii, Friedland-Goldman-Yomdin, Kheifets-Yuditskii), Schur analysis, moment problems and related topics (Boiko-Dubovoy, Dyukarev, Fritzsche-Kirstein-Mädler), extension of linear operators and linear relations (Dijksma-Langer, Hassi-de Snoo, Hassi -Wietsma) and non-commutative analysis (Ball-Bolotnikov, Cho-Jorgensen).
The articles of this volume will be reviewed individually.
Indexed articles:
\textit{Alpay, Daniel (ed.); Fritzsche, Bernd (ed.); Kirstein, Bernd (ed.)}, Editorial introduction, 1-8 [Zbl 07310471]
\textit{Dym, Harry}, Victor comes to Rehovot, 11-13 [Zbl 07310472]
\textit{Dyukarev, Yu. M.}, My teacher Viktor Emmanuilovich Katsnelson, 15-17 [Zbl 07310473]
\textit{Feldman, G. M.}, Some impressions of Viktor Emmanuilovich Katsnelson, 19-23 [Zbl 07310474]
\textit{Kirstein, Bernd}, The good fortune of maintaining a long-lasting close friendship and scientific collaboration with V. E. Katsnelson, 25-60 [Zbl 07310475]
\textit{Sodin, Mikhail}, A piece of Victor Katsnelson's mathematical biography, 61-75 [Zbl 07310476]
\textit{Ball, Joseph A.; Bolotnikov, Vladimir}, Interpolation by contractive multipliers between Fock spaces, 79-138 [Zbl 07310478]
\textit{Boiko, S. S.; Dubovoy, V. K.}, Regular extensions and defect functions of contractive measurable operator-valued functions, 139-228 [Zbl 07310479]
\textit{Cho, Ilwoo; Jorgensen, Palle}, Free-homomorphic relations induced by certain free semicircular families, 229-285 [Zbl 07310480]
\textit{Dijksma, Aad; Langer, Heinz}, Self-adjoint extensions of a symmetric linear relation with finite defect: compressions and Straus subspaces, 287-325 [Zbl 07310481]
\textit{Dyukarev, Yu. M.}, On conditions of complete indeterminacy for the matricial Hamburger moment problem, 327-353 [Zbl 07310482]
\textit{Favorov, S.; Golinskii, L.}, On a Blaschke-type condition for subharmonic functions with two sets of singularities on the boundary, 355-375 [Zbl 07310483]
\textit{Friedland, Omer; Goldman, Gil; Yomdin, Yosef}, Exponential Taylor domination, 377-386 [Zbl 07310484]
\textit{Fritzsche, Bernd; Kirstein, Bernd; Mädler, Conrad}, A closer look at the solution set of the truncated matricial moment problem \(\mathsf{M}[\alpha,\infty);(s_{j})_{j=0}^{m},{\preccurlyeq} ]\), 387-492 [Zbl 07310485]
\textit{Hassi, Seppo; De Snoo, H. S. V.}, A class of sectorial relations and the associated closed forms, 493-514 [Zbl 07310486]
\textit{Hassi, Seppo; Wietsma, Hendrik Luit}, Spectral decompositions of selfadjoint relations in Pontryagin spaces and factorizations of generalized Nevanlinna functions, 515-534 [Zbl 07310487]
\textit{Kheifets, A.; Yuditskii, P.}, Martin functions of Fuchsian groups and character automorphic subspaces of the Hardy space in the upper half plane, 535-581 [Zbl 07310488]