Pulse nonstationary processes generated by dynamic systems with random structure

Dynamic system with a random structure described by a set of the first-order stochastic differential equations (SDE) is used as a generating model of nonstationary pulse stochastic processes. Physically the system presents the combination of the so-called partial filters related to the isolated states of the considered process, switched by a Poissonian point process and excited by a vector delta-correlated stream of impulses with the randomly distributed energy. The filters’ outputs are components of the vector Markov continuous-jump process with statistics depending on the partial SDEs operators, intensity of switching process and distributions of the exciting impulses’ energies. The approach proposed was used as a simulation model of the Middleton “Class-A “generally non-Gaussian noise. The results demonstrate that the main features of statistical characteristics of the noise envelope are reproduced rather well with the help of a bistate system with random structure.     

Feedback multilevel control for continuous dynamic systems

An iterative technique for the derivation of a nearly optimal feedback control law for continuous dynamic systems with separable cost functions is developed based on the fundamental concepts of multilevel control. The developed technique comprises two major and subsequent stages. In the first stage, a two-level optimization structure is devised using the coordination by control method. An identification processthen follows in order to determine the constant gains of the dynamic controller utilizing the discrete quasilinearization algorithm. A three-level control structure is thus provided for the overall technique which can adaptively compute the unknown gains of the dynamic controller.     

产学研合作对企业技术能力结构的双元性影响

基于产学研合作与企业技术能力结构之间的三大视角,从短期互动和长期演化两个角度来对产学研合作与企业技术能力结构之间的活动机理进行分析。并以嘉宝莉化工集团为例,进行相关验证,结果发现互补型产学研合作能够有效提升企业技术能力广度,辅助型产学研合作能够有效提升企业技术能力深度。同时随着企业自主创新能力的提高:企业产学研合作的层次呈现出从"专有技术——应用共性技术——基础技术"的转换,企业对于产学研合作的依赖不断弱化,整个互动过程中外部资源引进类型呈现出"辅助型——互补和辅助型——互补型"的动态变化规律。     

Tracking policies for a class of dynamic production-inventory systems

In this paper, new results are established for generating tracking policies in aggregated production-inventory systems. A dynamic model is developed to characterize the evolution of targeted production, inventory and demand over time and incorporates the inventory, production and demand tracking errors as additional variables. The control variables are managerial decision variables on rate of production and advertisement. The developed model takes the form of linear system with time-varying delay. Tracking policies are then formulated and determined to ensure that the production-inventory tracking model achieves a desirable performance in terms of H_∞-measure. Numerical simulation is performed to illustrate the theoretical developments.     

协同场理论:电子商务系统蜕变动力学研究

电子商务系统演化复杂性的测量和评价,对于广大研究者是一项具有挑战性的课题.尝试将自然科学的场理论引入电子商务系统研究领域,提出“协同场”这一理论框架,通过对电子商务协同场的量子化描述,揭示电子商务系统蜕变的过程和水平,对系统协同的状态和方向做出判断和预测.在此动力学机制的基础上构建电子商务协同场方程,进一步完成了协同场的系统结构设计,从而把内源扰动与外源扰动的定量表达,以及对扰动的长期和短期的响应,容纳于一个统一的理论范式之中.     

Periodic sampled-data-based dynamic model control of switched linear systems

Sampled-data control as an effective mean of digital control has shown its prominent superiority in most practical industries and a zero-order holder (ZOH) is often introduced to maintain continuity of control in the field of sampled-data control system. However, it decreases the control accuracy in a certain extent since the state will be held invariably within each sampling interval. In order to improve the control accuracy, this paper proposes a dynamic model-based control strategy instead of ZOH for a class of switched sampled-data control systems. The model, which is built by abstracting the plant knowledge, is located at the controller side. The controller is set up based on the model state and it provides control input to the switched system. A fixed sampling period is adopted, under which a hybrid-dwell time switching condition is revealed by taking into account asynchronous switching. With reasonable design of switching condition, exponential stability of the closed-loop system can be guaranteed. Finally, advantages of our proposed method are presented through a numerical example by comparing with the result of ZOH-based control.     

A dynamic analytic approach to national innovation systems: The IC industry in Taiwan

The paper attempts to develop a mathematical model of the national innovation system (NIS) of Taiwan, particularly with regard to its integrated circuit (IC) industry. The method utilised is that of system dynamics (SD). Drawing on both questionnaire/in-depth interviews and computer simulation, the paper aims to increase insights into the dynamic processes of the Taiwanese IC industry system of innovation and understand the interdependence and interaction among capital flows, human resource flows, knowledge and technology flows, and product flows in the NIS. The paper concludes with some simulations of policy alternatives confronting the IC industry and the Taiwanese government.     

双暗态原子系统动力学行为的量子相干控制研究（英文）

量子相干控制前沿问题及应用研究是本世纪物理学前沿领域的重要研究内容。而基于暗态的量子相干控制技术已经导致了在相干布居捕获、绝热跟随、量子信息等多方面的应用。本论文主要进行双暗态原子系统动力学行为的若干量子相干控制研究，包括：双暗态四能级原子系统的绝热跟随特性研究；双暗态作用提高克尔非线性的新方案提出；自发辐射诱导相干实现非线性极化率的提高以及双通道高效四波混频过程的实现等。     

Some network thermodynamic models of coupled,dynamic physiological systems

A network thermodynamic method is presented which utilizes SPICE2, a computer program for simulating nonlinear electrical circuits, to model and simulate a number of nonlinear, dynamic physiological systems. Ordinary circuit diagrams are presented along with bond graph representations to facilitate translation into the simulation language. Examples discussed are a compartmental model of sodium flow in frog skin, coupled salt and volume flow in kidney proximal tubule and a cancer chemotherapeutic agent's permeation and metabolism in a cancer cell.     

Bilinear,dynamic single-ports and bond graphs of economic systems

It is shown that reinvestment and inventory effects can be described in 0431 0368 bond-graph terms. The associated differential equations in price and order-flow 0431 0368 V variables are bilinear forms. These effects are the fundamental inertia and compliance 0431 0368 V 3 of economic bond graph theory. Properties of the components and example market 0431 0368 V 3 graphs are discussed.     

需求函数为非线性的按订单生产企业动态定价的特性研究

按订单生产企业面对市场需求的变化,通常采用不同的策略来达到既定的目的。本文在需求函数为非线性的条件下,通过研究按订单生产企业动态定价模型,得出其定价的两个结论:在一定条件下,(1)价格是产量的增函数;(2)价格是剩余时间的增函数。     

全球生产网络与产业结构的动态优化——一个基于汽车产业的实例分析

以汽车产业为例,就全球生产网络的机制、如何分析全球生产网络环境里的国际分工和权力结构及以中国为代表的发展中国家如何通过融入全球生产网络实现产业结构动态优化等问题进行论述.     

浅论安防系统中的结构设计问题

从功能要求、人机要求和附加值提升三个方面,阐述了在安防系统中进行结构设计时,需要重点关注的问题,并给出了问题的答案和建议,对工程师从事相关工作具有一定的参考和借鉴作用。     

Phrase structure rewrite systems in information retrieval

Operational level automatic indexing requires an efficient means of normalizing natural language phrases. Subject switching requires an efficient means of translating one set of authorized terms to another. A phrase structure rewrite system called a Lexical Dictionary is explained that performs these functions. Background, operational use, other applications and ongoing research are explained.     

Mathematical aspects of static and dynamic stability problems in power systems

A power system is modelled by a system of parameterised differential-algebraic equations (DAEs) when it is operating normally; it is modelled by time-piecewise DAEs when a transient process occurs. The normal operation of power systems is related to the static stability problem; while the transient process is related to the dynamic stability problem. After categorising the stability problems in power systems into static and dynamic cases, mathematical formulations are proposed and mathematical problems related to them are studied using different mathematical tools. In the static case, the determination of feasibility region is related to solving algebraic equations; while in the dynamic case, identifying attraction domain is related to solving a DAE. For a power system, the determination of feasibility region is usually reduced to optimisation problems, while the determination of attraction domain and critical clearing time is related to the study of transient energy functions.     

Rendezvous problem of multiple linear uncertain systems under state-dependent dynamic networks

This paper studies the rendezvous problem for a class of linear systems with uncertain parameters and external disturbances under the state-dependent dynamic network, which is also called rendezvous network here. By combining potential function technique, distributed internal model design and adaptive control technique, a distributed adaptive state feedback control law is proposed to solve the rendezvous problem by completing the tasks of maintaining the connectivity of the rendezvous network, achieving asymptotic tracking, rejecting unknown external disturbances as well as handling uncertain parameters in the system dynamics, the leader system and the exosystem simultaneously.     

Switched observer-based dynamic event-triggered consensus of multi-agent systems under DoS attacks

This paper investigates the observer-based consensus control for high-order nonlinear multi-agent systems (MASs) under denial-of-service (DoS) attacks. When the DoS attacks appear, the communication channels are destroyed, and the blocked information may ruin the consensus of MASs. A switched state observer is designed for the followers to observe the leader’s state whether the DoS attacks occur or not. Then, a dynamic event-triggered condition is proposed to reduce the consumption of communication resources. Moreover, an observer-based and dynamic event-triggered controller is formulated to achieve leader-following consensus through the back-stepping method. Additionally, the boundedness of all closed-loop signals is obtained based on the Lyapunov stability theory. Finally, the simulation results demonstrate the effectiveness of the presented control strategy under DoS attacks.     

An application of the Udwadia-Kalaba dynamic formulation to flexible multibody systems

For the transient response analysis of a flexible slider-crank mechanism, the coordinate partitioning scheme and the Udwadia-Kalaba formulation are herein compared. The flexibility of the coupler has been modelled by means of a single Timoshenko beam element. The present analytical treatment can be viewed as an extension of the model discussed by Shabana in his textbook.     

Trilayer Stackelberg game for nonlinear systems using adaptive dynamic programming

This paper considers a trilayer Stackelberg game problem for nonlinear system with three players. A novel performance function is defined for each player, which depends on the coupling relationships with the other two players. The coupled Hamilton–Jacobi–Bellman (HJB) equations are built from the performance functions, and the optimal control polices of three players are obtained based on the Bellman’s principle of optimality. Because of the nonlinearity and coupling characteristics, a policy iteration (PI) algorithm with a three-layer decision-making framework is developed to online learn the coupled HJB equations. In order to implement the algorithm, we construct a critic-action neural network (NN) structure and design a NN approximation-based iteration algorithm. Finally, a simulation example is presented to verify the effectiveness of the proposed method.