An FE-Inexact Heterogeneous ADMM for Elliptic Optimal Control Problems with <Emphasis Type="Italic">L</Emphasis><Superscript>1</Superscript>-Control Cost

Elliptic PDE-constrained optimal control problems with L¹-control cost (L¹-EOCP) are considered. To solve L¹-EOCP, the primal-dual active set (PDAS) method, which is a special semismooth Newton (SSN) method, used to be a priority. However, in general solving Newton equations is expensive. Motivated by the success of alternating direction method of multipliers (ADMM), we consider extending the ADMM to L¹-EOCP. To discretize L¹-EOCP, the piecewise linear finite element (FE) is considered. However, different from the finite dimensional l1-norm, the discretized L¹-norm does not have a decoupled form. To overcome this difficulty, an effective approach is utilizing nodal quadrature formulas to approximately discretize the L¹-norm and L²-norm. It is proved that these approximation steps will not change the order of error estimates. To solve the discretized problem, an inexact heterogeneous ADMM (ihADMM) is proposed. Different from the classical ADMM, the ihADMM adopts two different weighted inner products to define the augmented Lagrangian function in two subproblems, respectively. Benefiting from such different weighted techniques, two subproblems of ihADMM can be efficiently implemented. Furthermore, theoretical results on the global convergence as well as the iteration complexity results o(1/k) for ihADMM are given. In order to obtain more accurate solution, a two-phase strategy is also presented, in which the primal-dual active set (PDAS) method is used as a postprocessor of the ihADMM. Numerical results not only confirm error estimates, but also show that the ihADMM and the two-phase strategy are highly efficient.     

A unified approach to construct generalized B-splines for isogeometric applications

Generalized B-splines have been employed as geometric modeling and numerical simulation tools for isogeometric analysis(IGA for short). However, the previous models used in IGA,such as trigonometric generalized B-splines or hyperbolic generalized B-splines, are not the unified mathematical representation of conics and polynomial parametric curves/surfaces. In this paper,a unified approach to construct the generalized non-uniform B-splines over the space spanned by{α(t), β(t), ξ(t), η(t), 1, t, ···, t~(n-4)} is proposed, and the corresponding isogeometric analysis framework for PDE solving is also studied. Compared with the NURBS-IGA method, the proposed frameworks have several advantages such as high accuracy, easy-to-compute derivatives and integrals due to the non-rational form. Furthermore, with the proposed spline models, isogeometric analysis can be performed on the computational domain bounded by transcendental curves/surfaces, such as the involute of circle, the helix/helicoid, the catenary/catenoid and the cycloid. Several numerical examples for isogeometric heat conduction problems are presented to show the effectiveness of the proposed methods.     

Robust reliable H∞ control for discrete-time Markov jump linear systems with actuator failures

The robust reliable H∞ control problem for discrete-time Markovian jump systems with actuator failures is studied. A more practical model of actuator failures than outage is considered. Based on the state feedback method, the resulting closed-loop systems are reliable in that they remain robust stochastically stable and satisfy a certain level of H∞ disturbance attenuation not only when all actuators are operational, but also in case of some actuator failures, The solvability condition of controllers can be equivalent to a feasibility problem of coupled linear matrix inequalities （LMIs）. A numerical example is also given to illustrate the design procedures and their effectiveness.     

Global Dynamics for an HIV Infection Model with Crowley-Martin Functional Response and Two Distributed Delays

In this paper, an HIV dynamics model with two distributed intracellular delays incorporating Crowley-Martin functional response infection rate is investigated. The authors take into account multiple stage disease transmission and the latently infected cells (not yet producing virus) in our system. The authors consider nonnegativity, boundedness of solutions, and global asymptotic stability of the system. By constructing suitable Lyapunov functionals and using the Lyapunov-LaSalle invariance principle, the authors prove the global stability of the infected (endemic) equilibrium and the diseasefree equilibrium for time delays. The authors have proven that if the basic reproduction number R₀ is less than unity, then the disease-free equilibrium is globally asymptotically stable, and if R₀ is greater than unity, then the infected equilibrium is globally asymptotically stable. The results obtained show that the global dynamic behaviors of the model are completely determined by the basic reproduction number R₀ and that the time delay does not affect the global asymptotic properties of the model.     

Semi-algebraically connected components of minimum points of a polynomial function

In a recent article, the authors provided an effective algorithm for both computing the global infimum of f and deciding whether or not the infimum of f is attained, where f is a multivariate polynomial over the field R of real numbers. As a complement, the authors investigate the semi- algebraically connected components of minimum points of a polynomial function in this paper. For a given multivariate polynomial f over R, it is shown that the above-mentioned algorithm can find at least one point in each semi-algebraically connected component of minimum points of f whenever f has its global minimum.     

CLT of wavelet estimator in semiparametric model with correlated errors

This paper considers the semiparametric regression model j/j= Xif3+g（U）+Vi（1 < i < n）, where（x_i,t_i） are known design points,/3 is an unknown slope parameter,g（·） is an unknown function, the correlated errors Vi=∑_j=-∞^∞c_je_i-jwith∑_j=-∞^∞|c_j|<∞,and e_i negatively associated random variables.Under appropriate conditions,the authors study the asymptotic normality for wavelet estimators ofβand g（·）.A simulation study is undertaken to investigate finite sample behavior of the estimators.     

New model for load-sharing k-out-of-n: G system with different components

On the basis of capacity flow model, a new model is developed for a load-sharing k-out-of-n： G system consisting of different components, to describe the increase of the same component＇s failure rates under different loads. All components have exponential life distributions and are nonrepairable in the system. Reliability of load- sharing 2-out- of-3： G system is calculated and some special cases for the system are discussed. The calculation and discussions show that the model is right and practical.     

Exchange rate forecasting with optimum singular spectrum analysis

Forecasting exchange rate is undoubtedly an attractive and challenging issue that has been of interest in different domains for many years. The singular spectrum analysis （SSA） technique has been used as a promising technique for time series forecasting including exchange rate series. The SSA technique is based upon two main choices： Window length, L, and the number of singular values, r. These values are very important for the reconstruction stage and forecasting purposes. Here the authors consider an optimum version of the SSA technique for forecasting exchange rates. The forecasting performances of the SSA technique for one-step-ahead forecast of six exchange rate series are used to find the best L and r.     

Improve Robustness and Accuracy of Deep Neural Network with L2,∞ Normalization

In this paper, the L_2,∞ normalization of the weight matrices is used to enhance the robustness and accuracy of the deep neural network(DNN) with Relu as activation functions. It is shown that the L_2,∞ normalization leads to large dihedral angles between two adjacent faces of the DNN function graph and hence smoother DNN functions, which reduces over-fitting of the DNN. A global measure is proposed for the robustness of a classification DNN, which is the average radius of th...     

Upwind finite volume element methods for one-dimensional semiconductor device

A fully discrete implicit Euler upwind finite volume element method is derived and studied for one-dimensional semiconductor device. Upwind scheme is introduced to deal with the convection-dominated diffusion equations in the semiconductor model. With different time steps for the electrostatic potential and the other unknown quantities, the computational procedure of the method is obtained. The local mass conservation laws are preserved under the framework of the upwind finite volume element schemes. A first-order accuracy in the L ²-norm is proved. Numerical experiments are given to validate the usefulness and efficiency of the method.     

AN ANP/DNP ANALYSIS OF ECONOMIC ELEMENTS IN TODAY＇S WORLD NETWORK ECONOMY

The network economy is a term for today’s global relationship among economic elements characterized by massive connectivity. The central act of the new era is to connect everything to everything in deep web networks at many levels of mutually interdependent relations, where resources and activities are shared, markets are enlarged and costs and risk are reduced. Network systems contain both positive and negative feedback. A variety of feedback processes create complex system behavior. For such a network the Analytic Network Process (ANP) approach seems to be very appropriate. The ANP method makes it possible to deal systematically with all kinds of dependence and feedback in the system. Dynamic models try to reflect changes in real or simulated time and take into account that the network model components are constantly evolving. Dynamic models use concepts of state variables, flows, and feedback processes. The Dynamic Network Process (DNP) is an extension of ANP that can deal with time dependent priorities in a networked economy. Petr Fiala is a Professor and the Deputy Head of the Department of Econometrics, University of Economics in Prague, the Czech Republic. He is a graduate of the University of Economics in Prague, Charles University in Prague, and the Rochester Institute of Technology in Rochester, NY, USA. He holds a PhD from the University in Prague. His current research interests include modeling of production systems, supply chain management, project management, and multicriteria and group decision making. He has been on study and research tours to Germany, Russia, the USA, India and Cuba. He is a member of professional societies for Operations Research and Multiple Criteria Decision Making and is the Vice President of the Czech Society of Operations Research and the Czech Republic representative in EURO (The Association of European Operational Research Societies). He is the author of books, lecture notes and papers in quantitative models and methods in management and economics.     

Efficient Asymmetrical Extended Designs Under Wrap-Around <Emphasis Type="Italic">L</Emphasis><Subscript>2</Subscript>-Discrepancy

The purpose of the present article is to introduce a class of mixed two- and three-level extended designs obtained by adding some new runs to an existing mixed two-and three-level design. A formulation of wrap-around L₂-discrepancy for the extended designs is developed. As a benchmark of obtaining (nearly) uniform asymmetrical extended designs, a lower bound to the wrap-around L₂-discrepancy for our proposed designs is established. Thorough numerical results are displayed, which provide further corroboration to the derived theoretical results.     

The biocybernetic approach as a basis for planning our environment

In this paper, Professor Vester introduces the readers ofSystems Practice to his biocybernetic approach to systems planning, an approach that he has shown to be fruitful both in concrete applications and in many best-selling didactic publications, including children's books and games. Based on this approach he proposes a “cybernetic senstivity model,” a conceptual framework for ecologically sound systems design based on a biocybernetic redefinition of conventional techniques of systems modeling and simulation. The author explains the basic structure of the model and presents eight pertinent biocybernetic principles of good-systems practice. (Editor).     

FCSR periodic multisequences with maximal joint N-adic complexity and large k-error joint N-adic complexity over Z/(N)

Complexity measures for keystream multisequences over Z/(N) play a crucial role in designing good stream cipher systems. This correspondence shows a general upper bound on k-error joint N-adic complexity of periodic multisequences over Z/(N), and establishes the existence of periodic N-adic multisequences over Z/(N) which simultaneously possess maximal joint N-adic complexity and large k-error joint N-adic complexity. Under some conditions the overwhelming majority of all T-periodic N-adic multisequences over Z/(N) with maximal joint N-adic complexity log _N (N ^T ? 1) have a k-error joint N-adic complexity close to log _N (N _T ? 1).     

A branch-and-cut approach to portfolio selection with marginal risk control in a linear conic programming framework

Marginal risk represents the risk contribution of an individual asset to the risk of the entire portfolio In this paper, we investigate the portfolio selection problem with direct marginal risk control in a linear conic programming framework. ＇The optimization model involved is a nonconvex quadratically constrained quadratic programming （QCQP） problem. We first transform the QCQP problem into a linear conic programming problem, and then approximate the problem by semidefinite programming （SDP） relaxation problems over some subrectangles. In order to improve the lower bounds obtained from the SDP relaxation problems, linear and quadratic polar cuts are introduced for designing a branch-and-cut algorithm, that may yield an e -optimal global solution （with respect to feasibility and optimality） in a finite number of iterations. By exploring the special structure of the SDP relaxation problems, an adaptive branch-and-cut rule is employed to speed up the computation. The proposed algorithm is tested and compared with a known method in the literature for portfolio selection problems with hundreds of assets and tens of marginal risk control constraints.     

设备部件延寿的灰色多指标畸变预测模型

针对设备部件延寿预测问题，首先，提出了上下限两种异常畸变指标，并给出灰色多指标延寿畸变预测模型的架构图和延寿预测示意图。其次，运用灰色系统方法分别构建了两阶段灰色预测模型，在第一阶段构建了灰色上下限畸变预测模型，得到下一次发生畸变的日期；在第二阶段构建了GM(1,1)模型，对设备部件延寿以及上下限指标的异常值进行预测。同时，对模型的预测精度进行检验和分析，并根据模型的预测结果确定了设备部件延寿的时间。最后，以半导体制造业设备靶材延寿为实际应用案例，验证了该模型的有效性和可行性，为合理制定部件的最优维护更换时间以及对降低企业运维成本具有重要指导意义。     

小波分解与Prophet框架融合的电离层VTEC预报模型

在全球导航卫星系统(global navigation satellite system,GNSS)的应用中,电离层垂直总电子含量(vertical total electron content,VTEC)是直接决定电离层延迟误差的重要参数.为提高其短期预报精度,在综合考虑地磁扰动影响的基础上,提出了小波分解与Prop...     

<Emphasis Type="Italic">L</Emphasis><Subscript>2</Subscript> disturbance attenuation for a class of time-delay Hamiltonian systems

This paper considers the problem of L ₂-disturbance attenuation for a class of time-delay port-controlled Hamiltonian systems. A γ-dissipative inequality is established by using a proper control law and a storage function. Then based on the Razumikhin stability theorem, a sufficient condition is proposed for the asymptotically stability of the closed-loop system. Finally, the authors investigate the case that there are time-invariant uncertainties belonging to some convex bounded polytypic domain and an L ₂ disturbance attenuation control law is proposed. Study of illustrative example with simulation shows that the presented method in this paper works very well in the disturbance attenuation of time-delay Hamiltonian systems.     

<Emphasis Type="Italic">H</Emphasis><Subscript>∞</Subscript> control for nonlinear stochastic Markov systems with time-delay and multiplicative noise

This paper is concerned with the H_∞ control problem for a class of nonlinear stochastic Markov jump systems with time-delay and system state-, control input- and external disturbancedependent noise. Firstly, by solving a set of Hamilton-Jacobi inequalities (HJIs), the exponential mean square H_∞ controller design of delayed nonlinear stochastic Markov systems is presented. Secondly, by using fuzzy T-S model approach, the H_∞ controller can be designed via solving a set of linear matrix inequalities (LMIs) instead of HJIs. Finally, two numerical examples are provided to show the effectiveness of the proposed design methods.