Fault reconstruction observer design for continuous-time systems with measurement disturbances via descriptor system approach

This paper addresses a problem of observer-based sensor fault reconstruction for continuous-time systems subject to sensor faults and measurement disturbances via a descriptor system approach. An augmented descriptor plant is first formulated, by assembling measurement disturbances and sensor faults into an auxiliary state vector. Then a novel descriptor state observer for the augmented plant is constructed such that simultaneous reconstruction of original system states, sensor faults and measurement disturbances are obtained readily. Sufficient conditions for the existence of the proposed observer are explicitly provided, and the application scope of the observer is further discussed. In addition, an extension of the proposed linear approach to a class of nonlinear systems with Lipschitz constraints is investigated. Finally, two numerical examples are simulated to illustrate the effectiveness of the proposed fault-reconstructing approaches.

System Approach to the Integration of Military and Civilian Productions in China

The author uses system analysis to provide system thinkings of the deepening reform of the management of defence science, technology and industry (DSTI) and investigate the system definition of DSTI, the system reform target, system operational mechanism, institutional structure, coordination and control functions and the orientation of conversion in China.

Open quantum system approach for heavy quark thermalization

We treat heavy quark as an open quantum system in a hot medium and rederive the stochastic Schrodinger equation(SSE)from the full Schrodinger equation for both heavy quarks and the medium.We apply the SSE to the dynamical evolutions of a heavy quark(as a system)in the static hot medium(as an environment).Heavy quarks interact with the medium via random scatterings,which exchange the momentum and phase factor randomly between two wave functions of the system and the environment.The exchange of momentum and phase factor results in the transition between different eigenstates of the system.These are included via an external stochastic potential in the Hamiltonian of SSE.Stochastic wave functions of a heavy quark are evolved with the stochastic external potential.The mean wave functions and corresponding momentum distributions of heavy quarks are obtained after the ensemble average over a large set of stochastic wave functions.We present the thermalization of heavy quarks in the static medium with different coupling strengths.

Optimal Cooperative Secondary Control for Islanded DC Microgrids via a Fully Actuated Approach

DC-DC converter-based multi-bus DC microgrids(MGs) in series have received much attention, where the conflict between voltage recovery and current balancing has been a hot topic. The lack of models that accurately portray the electrical characteristics of actual MGs while is controller design-friendly has kept the issue active. To this end, this paper establishes a large-signal model containing the comprehensive dynamical behavior of the DC MGs based on the theory of high-order fully actuated systems, and proposes distributed optimal control based on this. The proposed secondary control method can achieve the two goals of voltage recovery and current sharing for multi-bus DC MGs. Additionally, the simple structure of the proposed approach is similar to one based on droop control, which allows this control technique to be easily implemented in a variety of modern microgrids with different configurations. In contrast to existing studies, the process of controller design in this paper is closely tied to the actual dynamics of the MGs. It is a prominent feature that enables engineers to customize the performance metrics of the system. In addition, the analysis of the stability of the closed-loop DC microgrid system, as well as the optimality and consensus of current sharing are given. Finally, a scaled-down solar and battery-based microgrid prototype with maximum power point tracking controller is developed in the laboratory to experimentally test the efficacy of the proposed control method.

Analysis of the Energy and Environmental Sustainability of a Built Space System: The Case of Patte d’Oie University Campus in Ouagadougou

The aim of this study was to carry out a dynamic simulation of the energy and environmental performance of a built space system, with a view to assessing its energy and environmental class. The use of a simulation and modeling tool, supported by various methodological references, formed the basis of our approach. Adopting a systemic perspective, we described the structural and functional aspects of the systems making up built spaces, as well as the associated energy flows. Our approach was also based on a typology, taking into account typical days, structural and functional configurations at different scales and angles of observation. The analysis tool we developed in Java was applied to the built space system of the Patte d’Oie university campus in Ouagadougou. Annual electricity consumption was measured at 124387.34 kWh, closely aligned with the average annual electricity bill (125224.31 kWh), with a maximum relative deviation of 1%, followed by a carbon emission balance of 58337.66 kg eq CO2 per year. This validation confirmed the effectiveness of our tool. In addition, following the analysis of electricity consumption using our tool, the university campus was classified in energy class B and environmental class C. These results will be based on the emission factors of the energy mix of the West African Economic and Monetary Union (WAEMU) territory, with particular emphasis on Burkina Faso.

Fully-Actuated System Approach Based Optimal Attitude Tracking Control of Rigid Spacecraft with Actuator Saturation

In this paper,a fully-actuated system approach(FASA)based control method is proposed for rigid spacecraft attitude tracking with actuator saturation.First,a second-order fully-actuated form of spacecraft attitude error model is established by modified Rodrigues parameters(MRPs).The unknown total disturbance caused by inertial uncertainty and external disturbance is estimated by using extended state observer,then an FASA based controller is developed.Further,a control parameterization method is adopted to optimize the parameter matrices of FASA based controller with the actuator saturation.Finally,a numerical example is carried out to validate the effectiveness of the proposed scheme.

Fully Actuated System Approach for 6DOF Spacecraft Control Based on Extended State Observer

This paper deals with the problem of position and attitude tracking control for a rigid spacecraft.A fully actuated system(FAS)model for the six degree-of-freedom(6DOF)spacecraft motion is derived first from the state-space model by variable elimination.Considering the uncertainties from external disturbance,unknown motion information,and uncertain inertia properties,an extended state observer(ESO)is designed to estimate the total disturbance.Then,a tracking controller based on FAS approach is designed,and this makes the closed-loop system a constant linear one with an arbitrarily assignable eigenstructure.The solution to the parameter matrices of the observer and controller is given subsequently.It is proved via the Lyapunov stability theory that the observer errors and tracking errors both converge into the neighborhood of the origin.Finally,numerical simulation demonstrates the effectiveness of the proposed controller.

Stabilization via Fully Actuated System Approach:A Case Study

In this note,a benchmark example system which is not stabilizable by a smooth state feedback controller is considered with the fully actuated system(FAS)approach.It is shown that a smooth controller exists which drives the trajectories starting from a large domain in the initial value space to the origin exponentially.Such a result brings about a generalization of Lyapunov asymptotical stability,which is termed as global exponential sub-stability.The region of attraction is allowed to be an unbounded open set of the initial values with closure containing the origin.This sub-stability result may be viewed to be superior to some local stability results in the Lyapunov sense because the region of attraction is much larger than any finite ball containing the origin and meanwhile the feasible trajectories are always driven to the origin exponentially.Based on this sub-stabilization result,globally asymptotically stabilizing controllers for the system can be provided in two general ways,one is through combination with existing globally stabilizing controllers,and the other is by using a pre-controller to first move an initial point which is not within the region of attraction into the region of attraction.

A Fully Actuated System Approach for Stabilization of Discrete-Time Multiple-Input Nonlinear Systems with Distinct Input Delays

In this paper,the problem of stabilization is considered for discrete-time multiple-input nonlinear systems with distinct input delays law based on the fully actuated system approach.In order to compensate the input delays,a prediction scheme is presented to predict future states based on the closed-loop linear system.Then,a stabilizing law is constructed for nonlinear delayed systems by replacing the future states in the control law for the corresponding delay-free systems with their prediction.Finally,numerical examples are given to verify the effectiveness of the proposed approach.

A Systemic Approach to Integrated E-maintenance of Large Engineering Plants

Large engineering plants （LEPs） have certain unique features that necessitate a maintenance strategy that is a combination of both time and condition based maintenance. Although this requirement is appreciated to varying degrees by asset owners, applied research leading to a systematic development of such a maintenance strategy is the need of the day. Such a strategy should also adopt a wholesome ＂systemic＂ approach so that the realization of the overall objectives of maintenance is maximized. E-maintenance has several potential benefits for large engineering plants. In this paper, a three pronged strategy is suggested for the successful implementation of e-maintenance for LEPs. Firstly, an integrated condition and time based maintenance framework is proposed for LEPs. Secondly, reference is drawn to models for condition and time based maintenance at systemic levels. As a part of the ab initio development of a condition monitoring system for a LEP, one of the characteristics of the condition monitoring system, namely, predictability, is discussed in detail as a sample for a systemic study. Thirdly, emphasis is laid on the information and expertise available in the domain of plant design, operation and maintenance and the same is tapped for incorporation in maintenance decision making.

New Family of Exact Solutions and Chaotic Soltions of Generalized Breor-Kaup System in （2＋1）-Dimensions via an Extended Mapping Approach

Starting from an extended mapping approach, a new type of variable separation solution with arbitrary functions of generalized (2+1)-dimensional Broer-Kaup system (GBK) system is derived. Then based on the derived solitary wave solution, we obtain some specific chaotic solitons to the (2+1)-dimensional GBK system.

Feedback iterative learning control for time-delay systems based on 2D analysis approach

This paper deals with the iterative learning control （ILC） design for multiple-input multiple-output （MIMO）,time-delay systems （TDS）.Two feedback ILC schemes are considered using the so-called two-dimensional （2D） analysis approach.It shows that continuous-discrete 2D Roesser systems can be developed to describe the entire learning dynamics of both ILC schemes,based on which necessary and sufficient conditions for their stability can be provided.A numerical example is included to validate the theoretical analysis.

SOME DEVELOPMENTS IN THE STUDIES OF META-SYNTHESIS SYSTEM APPROACH

In the early 1990s, Professor Qian Xuesen (Tsien HsueShen) and his colleagues proposed the Metasynthesis system approach for solving the open complex giant system problems. The method emphasizes the synthesis of collected information and knowledge of various kinds of experts, and combining quantitative methods with qualitative knowledge. Later it is evolved into Hall of Workshop for Meta-Synthetic Engineering (HWMSE) which emphasizes to make use of breaking advances in information technologies. Then continuous endeavors have been taken to put those ideas into practice. With tremendous advances in networking and distributed computing technologies, past difficulties in implementation are disappearing together with farther understandings of HWMSE and fruitful results achieved in similar or relevant research fields in recent years in China. In this paper some of those development are introduced, together with some parallel research work abroad.

Systematic evaluation of the clinical nursing pathway with the GRADE approach applied to functional exercise in patients with hip replacements before and after surgery

Objective： To evaluate the effect of the clinical nursing pathway applied to functional exercise in patients with hip replacements before and after the operation. Methods： The China National Knowledge Infrastructure （CNKI）, WanFang Data, Chinese science and technology journal database （VIP）, PubMed, Web of Science, EMBASE, CBM and the Cochrane Library （2015-5） were searched for randomized controlled trials （RCTs） on clinical nursing pathways for func- tional exercise in patients with hip replacements before and after surgery from June 2015 to January 2010. The references included in the literature were also retrieved. To meet the literature standard, 2 reviewers independently selected and extracted data according to the inclusion criteria and assessed the risks of bias. RevMan 5.3 software was used in this meta-analysis. The quality of evidence was evaluated using grade profiler3.6 software, the level recommended for grading. Results： A total of 15 RCTs and 1248 patients were included. The meta-analysis showed that, in the clinical nursing path group, the Harris score of hip function [SMD = 3.35, 95%CI （2.53, 4.16）, P 〈 0.00001 ] and incidence of thrombosis embolism [RR - 0.28, 95%0 （0.15, 0.53）, P 〈 0.0001 ], pulmonary infection [RR = 0.33, 95%CI （0.14, 0.82）, P = 0.02], urinary retention [RR - 0.22, 95%CI （0.09, 0.52）, P = 0.0005], constipation [RR = 0.20, 95%0 （0.10, 0.40）, P 〈 0.00001 ], patients＇ satisfaction for nursing care [RR -- 1.26, 95%0 （1.17, 1.36）, P 〈 0.00001 ] and shortened hospitalization times [5MD = -1.91, 95%C! （ 2.39, -1.43）, P 〈 0.0001 ]were statistically significantly better than those in the control group. However, in reducing joint dislocations [Rig = 0.25, 95%C1 （0.05, 1.15）, P - 0.08], pressure ulcers [RR = 0.25, 95%0 （0.03, 2.19）, P = 0.21], and incidence of complications [RR = 0.42, 95%0 （0.15, 1.12）, P = 0.08], there was no statis- tically significant difference between the two groups. Funnel plot analysis of the average length of stay showed that there might be some publication bias in the literature. The GRADE evaluation results showed that the level of Harris scores for hip function was moderate and the incidence of thrombosis, urinary retention and satisfaction of patients regarding nursing were low, and the rest of the factors analyzed were very low. Conclusions： The effect of the clinical nursing pathway applied to functional exercises in patients with hip replacements before and after surgery was significantly better than that of routine nursing. However, it was restricted by the evaluation grade of the research results and the standardization and uniformity of the research. The results of the above study need to be verified by more high-quality RCTs.

A Systemic Approach to Evaluate the Flood Vulnerability for an Urban Study Case in Southern Italy

Currently, the urban flooding is one of the most concerning problems in hydraulic protection, both for the enormous number of people and the different elements (buildings, roads, vehicles, and so on) potentially exposed to risk, as well as the complexity of the territory at issue. At the practical level, vulnerability indicators are often predictably too narrow in their coverage of aspects of vulnerability. An important need remains to produce more conceptually informed vulnerability indicators or parameters and more satisfactory operational tools to assess weaknesses and resilience in coping with natural risks. In this paper, we present an innovative methodology that adopts a systemic approach to evaluate the vulnerability due to a flood scenario. The operative efficiency of the proposed GIS tool is validated in pilot application site, i.e. an urban area in Puglia Region, Southern Italy, on the basis of, studies surveys and damages carried out from a recent flood event occurred in the area. The model evaluates the direct structural damages and explores the potential operating conditions of the road network in case of the flood event. The resulting vulnerability assessment tool can guide evaluators towards a comprehensive understanding of strengths and fragilities of a territory and community where a flood occurs embedding and integrating as much as possible the multifaceted and articulated nature of an urban system.

Systems Approach to Mitotic Chromosome Motions

Recent experiments revealing possible nanoscale electrostatic interactions in force generation at kinetochores for chromosome motions have prompted speculation regarding possible models for interactions between positively charged molecules in kinetochores and negative charge on C-termini near the plus ends of microtubules. A clear picture of how kinetochores establish and maintain a dynamic coupling to microtubules for force generation during the complex motions of mitosis remains elusive. The molecular cell biology paradigm requires that specific molecules, or molecular geometries, for force generation be identified. However, it is possible to account for mitotic chromosome motions within a systems approach in terms of experimentally known cellular electric charge distributions interacting over nanometer distances.

A Systemic Approach Integrating Genetic, Mining and Management Visions: The Geologic and Mining Knowledge System

Following the example of other industrial activities, mining evaluation is now exposed to socio-economical and technological constraints which are unstable in quick evolution. The keys to its success are increasingly related to a methodology of work more scientific than ever. The Systemic Approach has broadly showed its effectiveness in numerous disciplinary fields, both scientific and engineering ones: Biology, Economy, Social and Management Sciences, Quality Management, Information Systems… Helped by technological progress, this approach has especially excelled in the management of spatial information (e.g. GIS). It constitutes therefore an excellent solution to the problems of mining evaluation by the integration of genetic, mining and managerial data within an Information System, thus optimizing scientific and economic valuation of mineral resources.

Road User Charging for Urban Freight Vehicles: A Systems Approach

Road user charging (RUC) has a long history as a mechanism to recover infrastructure maintenance and capital costs. The present RUC systems are facing issues such as transparency, cross-subsidization, environmental concerns and reducing revenue due to the likes of lessening fuel tax as vehicles become more efficient. Therefore, this paper reviews the strengths and weaknesses of the present RUC mechanisms implemented in the world with respect to stakeholder problems and demands of the freight industry and to describe the need for a more appropriate, practical and sustainable approach that can be used in the future. Finally, a model is proposed that is transparent and considers usage-based charging addressing most of the weaknesses highlighted in the models reviewed. Further, it considers externalities produced by heavy vehicles into account. The model has the potential to provide answers to key stakeholder issues and will lead to a sustainable freight transport system in the future. Encouraging fuel-efficient modes, optimization of loading, routing and logistics systems, and long term land use planning are a few of them.

Modeling approaches to pressure balance dynamic system in shield tunneling

In order to deal with modeling problem of a pressure balance system with time-delay, nonlinear, time-varying and uncertain characteristics, an intelligent modeling procedure is proposed, which is based on artificial neural network(ANN) and input-output data of the system during shield tunneling and can overcome the precision problem in mechanistic modeling(MM) approach. The computational results show that the training algorithm with Gauss-Newton optimization has fast convergent speed. The experimental investigation indicates that, compared with mechanistic modeling approach, intelligent modeling procedure can obviously increase the precision in both soil pressure fitting and forecasting period. The effectiveness and accuracy of proposed intelligent modeling procedure are verified in laboratory tests.