Mode-dependent H∞ Filtering for Time-varying Delays Neutral Jump Systems Based on FWM Technique

Guowei Zhao,Guangming Zhuang,Jianwei Xia,Wei Sun,Junsheng Zhao,Minsong Zhang 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.6

This paper is concerned with the problem of mode dependent H∞ filter for uncertainty Markovian jump system with neutral delay and retarded time-varying delay. By using free weight matrix (FWM) technique, the stability conditions of delay dependent are obtained under the framework of Lyapunov stability theory. Based on those result, the delay dependent conditions for full order and mode dependent Markovian jump linear filters are gained, which are expressed by Linear matrix inequalities (LMIs). Finally, a numerical example and a PEEC practical example are employed to prove the validity of the results.

Effect of different spacers for performance enhancement on white organic light-emitting devices based on double emissive layers with homogeneous p-/n-type host

Junsheng Yu,Juan Zhao,Lei Zhang,Jian Zhong 한국물리학회 2012 Current Applied Physics Vol.12 No.4

White organic light-emitting devices (WOLEDs) based on phosphorescent blue and yellow emitters were fabricated, while p-type di-(4-(N,N-ditolyl-amino)-phenyl)cyclohexane (TAPC) and n-type 2,20,200-(1,3,5-benzenetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi) were separately utilized as a homogeneous host for both blue and yellow emissive layers (EMLs). Then, various spacers were inserted between the two EMLs for performance characterization. The results showed that for the TAPC-host devices, a device using 4,7-diphenyl-1,10-phenanthroline (Bphen) as the spacer had a maximum current efficiency (CE) of 11.3 cd/A, while stable white light emission with Commission Internationale del’Eclairage (CIE) coordinates of (0.394, 0.435) at a bias of 5 V was observed. Similarly, among the TPBi-host devices, a device using 4,40-bis(carbazol-9-yl)biphenyl (CBP) as the spacer exhibited a maximum CE of 18.1 cd/A,accompanied by negligible color variation with the CIE coordinates of (0.284,0.333) at 5 V. For the double-EML devices, the improved device efficiency and color stability by introducing proper spacer was attributed to broadened recombination region and efficient energy transfer between the EMLs.

Fracture behaviors of tunnel lining caused by multi-factors: A case study

Zhao, Yiding,Zhang, Yongxing,Yang, Junsheng Techno-Press 2019 Advances in concrete construction Vol.8 No.4

The cracking and spalling caused by fracture of concrete lining have adverse impacts on serviceability and durability of the tunnel, and the subsequent maintenance work for damaged structure needs to be specific to the damaging causes. In this paper, a particular case study of an operational tunnel structure is presented for the serious cracking and spalling behaviours of concrete lining, focusing on the multi-factors inducing lining failure. An integrated field investigation is implemented to characterize the spatial distribution of damages and detailed site situations. According to results of nondestructive inspection, insufficient lining thickness and cavity behind lining are the coupled-inducement of lining failure bahaviors. To further understanding of the lining structure performance influenced by these multiple construction deficiencies, a reliable numerical simulation based on extended finite element method (XFEM) is performed by using the finite element software. The numerical model with 112 m longitudinal calculation, 100 m vertical calculation and 43 m vertical depth, and the concrete lining with 1450 solid elements are set enrichment shape function for the aim of simulating cracking behavior. The numerical simulation responses are essentially in accordance with the actual lining damaging forms, especially including a complete evolutionary process of lining spalling. This work demonstrates that the serious lining damaging behaviors are directly caused by a combination of insufficient thickness lining and cavity around the surrounding rocks. Ultimately, specific maintenance work is design based on the construction deficiencies, and that is confirmed as an efficient, time-saving and safe maintenance method in the operational railway tunnel.

Structural monitoring and analyses on the stability and health of a damaged railway tunnel

Zhao, Yiding,Yang, Junsheng,Zhang, Yongxing,Yi, Zhou Techno-Press 2021 Advances in concrete construction Vol.11 No.5

In this paper, a study of stability and health of a newly-built railway tunnel is presented. The field test was implemented to monitor the secondary lining due to the significant cracking behaviors influenced the stability and health of the tunnel structure. Surface strain gauges were installed for monitoring the status of crack openings, and the monitoring outputs demonstrated that the cracks were still in the developing stage. Additionally, adjacent tunnel and poor condition of surrounding rock were identified as the causes of the lining cracking by systematically characterizing the crack spatial distribution, tunnel site and surrounding rock conditions. Reconstruction of partial lining and reconstruction of the whole secondary lining were designed as the maintenance projects for different cracking regions based on the construction feasibility. For assessing the health conditions of the reinforced lining, embedded strain gauges were set up to continuously measure the strain and the internal force of the reconstructed structures. For the partially reconstructed lining, the outputs show the maximum tensile elongation is 0.018 mm during 227 days, which means the structure has no obvious deformation after maintenance. The one-year monitoring of full-section was implemented in the other two completely reconstructed cross-sections by embedded strain gauge. The outputs show the reconstructed secondary lining has undertaken the pressure of surrounding rock with the time passing. According to the calculated compressive and tensile safety factors, the completely reconstructed lining has been in reliable and safe condition during the past year after reinforcement. It can conclude that the aforementioned maintenance projects can effectively ensure the stability and health of this tunnel.

Output Feedback Stabilization of Stochastic Nonlinear Time-varying Delay Systems with Unknown Output Function

Mengmeng Gao,Junsheng Zhao,Jianwei Xia,Zong-Yao Sun 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.9

This paper addresses the problem of output feedback stabilization for stochastic nonlinear time-varying delay systems with an unknown output function. A remarkable feature of the system to be considered is the simultaneous presence of a continuous unknown sensitivity function and the stochastic disturbances, which have not been treated together before. A new observer is designed by using a dynamic gain without using the information on unknown time-varying delay and nonlinearities. With the aid of the observer, an output feedback controller is constructed by the stochastic double-domination method, where two gains are used to handle the unknown output function and nonlinearities. The performance of the system is analyzed in detail via two integral Lyapunov functions. Finally, the efficiency of the control strategy is illustrated by a simulation example.

Global Output Feedback Stabilization for Stochastic Nonlinear Systems with Multiple Uncertainties

Yanghe Cao,Junsheng Zhao,Zong-yao Sun 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.7

This manuscript addresses the problem of output feedback stabilization for stochastic nonlinear zerodynamics systems with multiple uncertainties. A distinctive feature of the systems is the dynamic/parametric uncertainties, the stochastic and the unknown continuous output function disturbances, which have not been considered together yet. Then an output-feedback stabilizer and an observer are designed, where a dynamic gain is carried out to address the unknown nonlinearities and a constant gain is carried out to address unknown measurement sensitivity. The controller makes sure that the equilibrium at the origin of the closed-loop systems that have an almost surely unique solution is stochastic stable in probability. Finally, a simulation example is presented to illustrate the efficiency of the designed controller.

Fast Finite-time Adaptive Fuzzy Control for Stochastic Nonlinear System

Yixuan Yuan,Junsheng Zhao,Yaqi Gu,Xuejing Zhao,Zong-Yao Sun 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.12

In this article, we solve the fast finite-time stabilization as well as adaptive fuzzy control design issues for a class uncertain stochastic nonlinear systems. Firstly, a new fast finite-time control scheme is proposed in virtue of generalizing the fast finite-time adaptive control strategy for deterministic systems to the stochastic case. Next, a novel adaptive fuzzy control strategy is developed to simultaneously deal with the stochastic nonlinear systems with completely unknown nonlinearities as well as the disturbances term. Then, stability analysis have been given based on a Jensen’s inequality. Finally, two simulations examples is presented to illustrate the effectiveness of the proposed control scheme.

Panorama Measurement Based on Spherical Projective Geometry

Shuai Liu,Lingli Zhao,Junsheng Li 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.2

Previous panoramic studies focused on image stitching and the panoramic camera development. In recent years, people began to focus on panoramic scalability issues, the existed methods adopt traditional photogrammetric methods for data processing based on a multi-directional panorama images, using a large number of control points and combined bundle adjustment. Indeed, panorama itself is a kind modeling method, it is completely unnecessary to reconstruct the panoramic entire scene for measurement. So in this paper, we focus on a kind of panorama measurement from spherical projective geometry we studied and constructed the relative, absolute orientation and measurable algorithms based on spherical stereo pair panorama in order to achieve panoramic measurement in the process of panorama roaming. The experiment shows that the approach is much validated, and something useful is obtained.

Practical Tracking Control for High-order Nonlinear Systems With Dynamic Uncertainties and Unknown Powers via Event-triggered Mechanism

Jiling Ding,Weihai Zhang,Junsheng Zhao 제어·로봇·시스템학회 2024 International Journal of Control, Automation, and Vol.22 No.4

This paper studies the problem of output regulation for a class of high-order nonlinear systems with dynamic uncertainties and unknown powers. Based on the characters of input-to-state stable Lyapunov function and the technique of changing supply rate, a partial-state feedback controller is designed under event-triggered mechanism framework. In the proposed control law, an adaptive dynamic gain is constructed to deal with system uncertainties and eliminate the bad effect of the event-triggered sampling error, and a term of higher power is introduced to compensate the unknown system powers. It is verified that the output tracking error converges into any prescribed small set of the origin and all the closed-loop signals are globally bounded by the proposed partialstate feedback controller, while the Zeno phenomenon is avoided. The effectiveness of the proposed scheme is verified by some simulation results.

Event-triggered Extended Dissipative Control for Networked Singular Systems

Meiyu Li,Jianwei Xia,Junsheng Zhao,Huasheng Zhang,Hao Shen 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.1

In this paper, an event-triggered extended dissipative control problem for networked singular systems isinvestigated, where the extended dissipativity analysis unifies the H∞ performance, L2 −L∞ performance, passivity,(Q,S,R)-dissipativity in one framework. Under the event-triggered scheme, the closed-loop system is modeled asa time-delay system. Some sufficient conditions for extended dissipativity are developed and presented in terms oflinear matrix inequalities (LMIs). Then the design of the state feedback controller becomes a matter of solving aset of LMIs. Finally, a numerical example is provided to illustrate the effectiveness of the proposed method.