This paper proves three statements of Schubert about cuspal cubic curves in a plane by using the concept of generic point of Van der Waerden and Weil and Ritt-Wu methods. They are relations of some special lines: 1) For a given point, all the curves containing this point are considered. For any such curve, there are five lines. Two of them are the tangent lines of the curve passing through the given

For evaluating the influence of the Chinese renminbi (RMB) joining in the special drawing right (SDR) basket on RMB’s internationalization, the authors systemically study the risk spillover networks and examine the dynamic relationship of exchange rates among the SDR currencies including the US dollar (USD), European Union euro (EUR), Japanese yen (JPY) and British pound (GBP). The empirical results

In computer algebra, it remains to be challenging to establish general computational theories for determining the equivalence of indexed polynomials. In previous work, the author solved the equivalence determination problem for Riemann tensor polynomials by extending Gröbner basis theory. This paper extends the previous work to more general indexed polynomials that involve no eliminations of indices

In many regression analysis, the authors are interested in regression mean of response variate given predictors, not its the conditional distribution. This paper is concerned with dimension reduction of predictors in sense of mean function of response conditioning on predictors. The authors introduce the notion of partial dynamic central mean dimension reduction subspace, different from central mean

This paper presents sufficient and necessary conditions for the propagator controllability of a class of infinite-dimensional quantum systems with SU(1, 1) dynamical symmetry through the isomorphic mapping to the non-unitary representation of SU(1, 1). We prove that the elliptic condition of the total Hamiltonian is both necessary and sufficient for the controllability and strong controllability. The

In many practical classification problems, datasets would have a portion of outliers, which could greatly affect the performance of the constructed models. In order to address this issue, we apply the group method of data handing (GMDH) neural network in outlier detection. This study builds a GMDH-based outlier detection (GOD) model. This model first implements feature selection in the training set

Goethite iron precipitation process is a key step in direct leaching process of zinc, whose aim is to remove ferrous ions from zinc sulphate solution. The process consists of several cascade reactors, and each of them contains complex chemical reactions featured by strong nonlinearity and large time delay. Therefore, it is hard to build up an accurate mathematical model to describe the dynamic changes

This paper addresses the distributed adaptive optimization problem over second-order multi-agent networks (MANs) with nonuniform gradient gains. A general convex function consisting of a sum of local differentiable convex functions is chosen as the team objective function. First, based on the local information of each agent’s neighborhood, a novel distributed adaptive optimization algorithm with nonuniform

This paper proposes a double penalized quantile regression for linear mixed effects model, which can select fixed and random effects simultaneously. Instead of using two tuning parameters, the proposed iterative algorithm enables only one optimal tuning parameter in each step and is more efficient. The authors establish asymptotic normality for the proposed estimators of quantile regression coefficients

It is an important problem in topology to verify whether two embeddings are isotopic. This work proposes an algorithm for computing Haefliger-Wu invariants for isotopy based on algebraic topological methods. Given a simplicial complex embedded in the Euclidean space, the deleted product of it is the direct product with diagonal removed. The Gauss map transforms the deleted product to the unit sphere

The world energy demand is increasing due to rapid growth in the global economy, industrialization, and urbanization. Pakistan is also confronted with increasing energy demand on one hand and is confronted with the challenge of energy demand-supply gap on the other hand. Since energy is the major driver for growth, it becomes important to investigate the trends of energy consumption in a country and

This paper investigates a time-inconsistent stochastic linear-quadratic problem with regime switching that is characterized via a finite-state Markov chain. Open-loop equilibrium control is studied in this paper whose existence is characterized via Markov-chain-modulated forward-backward stochastic difference equations and generalized Riccati-like equations with jumps.

Linear regression models for interval-valued data have been widely studied. Most literatures are to split an interval into two real numbers, i.e., the left- and right-endpoints or the center and radius of this interval, and fit two separate real-valued or two dimension linear regression models. This paper is focused on the bias-corrected and heteroscedasticity-adjusted modeling by imposing order constraint

To save the calculations of Jacobian, a multi-step Levenberg-Marquardt method named Shamanskii-like LM method for systems of nonlinear equations was proposed by Fan (2013). Its convergence properties have been proved by using a trust region technique under the local error bound condition. However, the authors wonder whether the similar convergence properties are still true with standard line searches

This paper considers output tracking for a one-dimensional wave equation with general disturbance which includes both internal nonlinear uncertainty and external disturbance. The performance output is non-collocated to the control. The disturbance is estimated by an essentially extended state observer from active disturbance rejection control and the difficulty caused by the non-collocated configuration

This paper generalizes the factorization theorem of Gouveia, Parrilo and Thomas to a broader class of convex sets. Given a general convex set, the authors define a slack operator associated to the set and its polar according to whether the convex set is full dimensional, whether it is a translated cone and whether it contains lines. The authors strengthen the condition of a cone lift by requiring not

This paper considers the fully coupled forward-backward stochastic functional differential equations (FBSFDEs) with stochastic functional differential equations as the forward equations and the generalized anticipated backward stochastic differential equations as the backward equations. The authors will prove the existence and uniqueness theorem for FBSFDEs. As an application, we deal with a quadratic

The asymptotic behaviour of solutions of three-dimensional nonlinear elastodynamics in a thin shell is considered, as the thickness h of the shell tends to zero. Given the appropriate scalings of the applied force and of the initial data in terms of h, it’s verified that three-dimesional solutions of the nonlinear elastodynamic equations converge to solutions of the time-dependent von KMorármMorán

Cryptocurrency, as an emerging social phenomenon, has attracted great research attentions and starts to form a new research area in the past decade. A thorough review of the existing cryptocurrency literatures helps us to understand the status-quo and the promising research future of this emerging field. This paper provides a systematic review of the cryptocurrency literatures by employing bibliometrics

This paper builds an agent-based model to study the impact of analyst competition on analyst optimism. Two strategies (a catering strategy and a pressure strategy) are used to model analysts conflicts of interest between listed corporations and institutional clients. The finding suggests that the relationship between competition and analyst optimism is nonlinear. Low-level competition generates more

In this paper, the event-triggered consensus for linear discrete-time multi-agent systems with parameter uncertainties is investigated. The parameter uncertainty is assumed to be norm-bounded. An event-triggered consensus protocol based on the predictive control method is proposed to make the multi-agent system achieve consensus. And for the design of the consensus protocol, the problem of estimating

This paper addresses the global output feedback regulation problem for a class of uncertain feedforward time-delay nonlinear systems. Unlike to the previous works, the nonlinear functions in the class of systems under consideration are dominated by an input-output function multiplied by an unknown parameter and linear unmeasured states. By using only one dynamic gain and an appropriate Lyapunov-Krasovskii

This paper presents two distributed stochastic source seeking controllers to navigate multiple vehicles to seek the signal source, using the measurements of the signal field at their own positions and information of their neighbors. The first controller utilizes neighbors’ measurements of the signal field and the second controller utilizes relative positions between neighbors. The effectiveness of

In this paper, the problems of robust stability and stabilization, for the first time, are studied for delayed fractional-order linear systems with convex polytopic uncertainties. The authors derive some sufficient conditions for the problems based on linear matrix inequality technique combined with fractional Razumikhin stability theorem. All the results are obtained in terms of linear matrix inequalities

In this paper, the consensus problem is investigated for discrete-time multi-agent systems with additive process noises. Due to the presence of additive noises in the system dynamics, consensus cannot be achieved. The main contribution of this paper is to give the exact consensus error. In particular, control gain depending on the agent dynamics and network topology is designed based on the technique

Over the last four decades, a severe deterioration in air quality has accompanied China’s rapid industrialization. As a result, the Chinese government has implemented stricter policies and regulation to control air pollution. In this paper, the authors create a measure of government policies on air pollution by tracking all pollution-related government announcements in Chinese newspapers. The authors

This paper investigates the optimal control problem arising in advertising model with delay. The authors reformulate the problem in Hilbert space by stochastic evolution equation and consider the optimal control problem of controlled stochastic evolution system. The necessary and sufficient optimality conditions of the control are established. The proposed approach is different from most existing studies

This paper utilizes a switched systems approach to deal with the problem of fault detection (FD) for uncertain delta operator networked control systems (NCSs) with packet dropouts and timevarying delays. Uncertainties exist in the matrices of the systems and are norm-bounded time-varying. Two parts of packet dropouts are considered in this paper: From sensors to controllers, and from controllers to

The significance of the existing analysis methods in complex networks and easy access to the ever-increasing volume of information present the emergence of proposing new methods in various fields based on complex system ideas. However, these systems are usually faced with various random failures and intelligent attacks. Due to the nature of the components’ behaviors, the occurrence of the failures

Necessary and sufficient conditions for the exact controllability and approximate controllability of a singular distributed parameter system are obtained. These general results are used to examine the exact controllability and approximate controllability of the Dzektser equation in the theory of seepage.

This paper investigates the mean square stability problem for impulsive stochastic delayed reaction-diffusion equations. By employing stochastic analysis theory, impulsive differential inequality technique and Razumikhin method, comparison principle for impulsive stochastic delayed reactiondiffusion equations is firstly established. Then, by using the comparison principle, some sufficient conditions

As an innovative concept, an optimal predictive impedance controller (OPIC) is introduced here to control a lower limb rehabilitation robot (LLRR) in the presence of uncertainty. The desired impedance law is considered to propose a conventional model-based impedance controller for the LLRR. However, external disturbances, model imperfection, and parameters uncertainties reduce the performance of the

This paper studies the leaderless consensus problems of multi-agent systems with input saturation and intermittent communication over directed networks. Both the state feedback and the output feedback consensus algorithms are developed based on low gain feedback approach. The convergence of the trajectories of all agents can be achieved by these proposed algorithms, if the communication topology has

Robust fuzzy filterings for a class of nonlinear stochastic systems with infinite Markov jump are explored based on T-S fuzzy model approach in this paper. First of all, the exponentially mean square stable filter with a prescribed Hoo performance is designed via linear matrix inequalities (LMIs). Secondly, H2/H∞ fuzzy filtering is solved in terms of LMIs by minimizing the estimation error energy under

This paper proposes a synchronous parallel block coordinate descent algorithm for minimizing a composite function, which consists of a smooth convex function plus a non-smooth but separable convex function. Due to the generalization of the proposed method, some existing synchronous parallel algorithms can be considered as special cases. To tackle high dimensional problems, the authors further develop

In this paper, a cooperative adaptive control of leader-following uncertain nonlinear multiagent systems is proposed. The communication network is weighted undirected graph with fixed topology. The uncertain nonlinear model for each agent is a higher-order integrator with unknown nonlinear functions, unknown disturbances and unknown input actuators. Meanwhile, the gains of input actuators are unknown

In this paper, the regression function comparison for paired data is studied. The proposed test statistic is based on the weighted integral of characteristic function marked by the difference of responses. There are several merits of the proposed statistic. For instance, it takes a simple V-statistic form. No bandwidth is needed. No moment conditions are required for covariates. It can be applied to

This paper presents a new method for visualizing implicit real algebraic curves inside a bounding box in the 2-D or 3-D ambient space based on numerical continuation and critical point methods. The underlying techniques work also for tracing space curve in higher-dimensional space. Since the topology of a curve near a singular point of it is not numerically stable, the authors trace only the curve

This paper proposes three fractional discrete chaotic systems based on the Rulkov, Chang, and Zeraoulia-Sprott rational maps. The dynamics of the proposed maps are investigated by means of phase plots and bifurcations diagrams. Adaptive stabilization schemes are proposed for each of the three maps and the convergence of the states is established by using the Lyapunov method. Furthermore, a combination

This paper presents a new model of discrete time Geo/Geo/1 repairable queueing system with pseudo-fault, negative customers and multiple working vacations. The authors assume that system service may be interrupted by breakdown or pseudo-fault, this system may become disabled only when it is in a regular busy period, and negative customers adopt two types of typical killing strategies. In this paper

Model average receives much attention in recent years. This paper considers the semiparametric model averaging for high-dimensional longitudinal data. To minimize the prediction error, the authors estimate the model weights using a leave-subject-out cross-validation procedure. Asymptotic optimality of the proposed method is proved in the sense that leave-subject-out cross-validation achieves the lowest

In this paper, an adaptive observer for robust control of robotic manipulators is proposed. The lumped uncertainty is estimated using Chebyshev polynomials. Usually, the uncertainty upper bound is required in designing observer-controller structures. However, obtaining this bound is a challenging task. To solve this problem, many uncertainty estimation techniques have been proposed in the literature

In social networks, the structural balance is a state of a group of individuals (nodes) with established mutual relationships (connection relationships) between them. It is easy to see that a social network can be described by a complex dynamical network model composed of the nodes subsystem (NS) and the connection relationships subsystem (CS), where the two subsystems are usually coupled with each

This paper investigates the hypothesis test of the parametric component in partial functional linear regression models. Based on a rank score function, the authors develop a rank test using functional principal component analysis, and establish the asymptotic properties of the resulting test under null and local alternative hypotheses. A simulation study shows that the proposed test procedure has good

This paper considers the equilibrium behavior of customers in a Markovian queue with setup times and partial failures, where the reactivated server must go through a period of setup time to reach the normal working state and a failure can occur at any time during the normal service. When a partial failure occurs, the server continues to serve the customers on spot at a low rate and does not admit a

For the heteroscedastic regression model Yi = xiβ + g(ti) + σiei, 1 ≤ i ≤ n, where \(\sigma_i^2\) = f(ui), the design points (xi, ti, ui) are known and nonrandom, g(・) and f(・) are defined on the closed interval [0, 1]. When f(・) is known, we investigate the asymptotic normality for wavelet estimators of β and g(・) under ei, 1 ≤ i ≤ is a sequence of identically distributed α-mixing errors; when f(・)

This paper explores the impacts of the universal two-child policy on Beijing’s population in the long term. It gives a detail estimation of Beijing population considering the latest fertility and immigration policy and can help related government department management population. The cohortcomponent method based on a net migration was applied to project population by age for Beijing from 2020 to 2050

In this paper, iterative learning control (ILC) is considered to solve the tracking problem of time-varying linear stochastic systems with randomly varying trial lengths. Using the two-dimensional Kalman filtering technique, the authors can establish a recursive framework for designing the learning gain matrix along both time and iteration axes by optimizing the trace of input error covariance matrix

In the era of big data, stock markets are closely connected with Internet big data from diverse sources. This paper makes the first attempt to compare the linkage between stock markets and various Internet big data collected from search engines, public media and social media. To achieve this purpose, a big data-based causality testing framework is proposed with three steps, i.e., data crawling, data

This paper studies the general decay synchronization (GDS) of a class of recurrent neural networks (RNNs) with general activation functions and mixed time delays. By constructing suitable Lyapunov-Krasovskii functionals and employing useful inequality techniques, some sufficient conditions on the GDS of considered RNNs are established via a type of nonlinear control. In addition, one example with numerical

The motion coordination formation control problem for a class of non-linear system is considered in this paper, where networked induced time-delays exist in the feedback channel of each agent and in communication channels between agents. As a foundation work, a coordination formation controller in discrete-time domain that without time-delay is provided firstly. Based on the above results, a motion

Analyzing the underlying characteristics of trade values movements has attracted much attention in the domestic research. However, the proposed understanding of these characteristics is limited by the intrinsic complexity of the imports/exports. Since economic systems are naturally organized by hierarchies, a novel hierarchical model is proposed in this paper to forecast China’s foreign trade. First

Time consistency is an important property of any solution to a cooperative dynamic game. If the solution satisfies this property, players do not need to revise it and break a cooperative agreement. Strong time consistency is a stricter property which is applicable to cooperative set solutions. In this paper, the authors examine a class of linear-state games which come into use in many applications

Credit scoring is one of the key problems in financial risk managements. This paper studies the credit scoring problem based on the set-valued identification method, which is used to explain the relation between the individual attribute vectors and classification for the credit worthy and credit worthless lenders. In particular, system parameters are estimated by the set-valued identification algorithm

This paper concerns the identification problem of scalar errors-in-variables (EIV) systems with general nonlinear output observations and ARMA observation noises. Under independent and identically distributed (i.i.d.) Gaussian inputs with unknown variance, recursive algorithms for estimating the parameters of the EIV systems are presented. For general nonlinear observations, conditions on the system

Inspired by real world phenomena, in this paper, the authors present a power law evolutional network model with degree exponent β < 2. Combinatorial probabilistic method is applied to the theoretical analysis of the presented model. In the proposed model, each time stamp the number of links among a newly added node and old ones follows Poisson distribution with parameter λ and selection probability

Any potential damage may be severe once an accident occurs involving hazardous materials. It is therefore important to consider the risk factor concerning hazardous material supply chains, in order to make the best inventory routing decisions. This paper addresses the problem of hazardous material multi-period inventory routing with the assumption of a limited production capacity of a given manufacturer

Nonlinear feedback shift registers (NFSRs) are widely used as building blocks in the design of stream ciphers. Let NFSR(f) be an NFSR with the characteristic function f and let G(f) be the set of output sequences of NFSR(f). For a given NFSR(f), if there exists an affine Boolean function l such that G(l) ⊆ G(f), then G(l) is called an affine sub-family of NFSR(f). In this paper, by skillfully combining

Since 2010, Chinese government has introduced a series of administrative policies to limit speculation in the housing market to stabilize price fluctuations and keep the housing market in a healthy state of development. In order to investigate whether administrative policy can play its due role, this paper constructs a comprehensive bottom-up housing market heterogeneous households multiagent model

Intersection computation of convex sets is a typical problem in distributed optimization. In this paper, the algorithm implementation is investigated for distributed convex intersection computation problems. In a multi-agent network, each agent is associated with a convex set. The objective is for all the agents to achieve an agreement within the intersection of the associated convex sets. A distributed